Sample records for nasa rotating-wall bioreactor

  1. Bioreactor rotating wall vessel

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells.

  2. Salmonella Typhimurium grown in a rotating wall bioreactor

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Salmonella typhimurium appears green in on human intestinal tissue (stained red) cultured in a NASA rotating wall bioreactor. Dr. Cheryl Nickerson of Tulane University is studying the effects of simulated low-g on a well-known pathogen, Salmonella typhimurium, a bacterium that causes two to four million cases of gastrointestinal illness in the United States each year. While most healthy people recover readily, S. typhimurium can kill people with weakened immune systems. Thus, a simple case of food poisoning could disrupt a space mission. Using the NASA rotating-wall bioreactor, Nickerson cultured S. typhimurium in modeled microgravity. Mice infected with the bacterium died an average of three days faster than the control mice, indicating that S. typhimurium's virulence was enhanced by the bioreactor. Earlier research showed that 3 percent of the genes were altered by exposure to the bioreactor. Nickerson's work earned her a 2001 Presidential Early Career Award for Scientists and Engineers.

  3. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The heart of the bioreactor is the rotating wall vessel, shown without its support equipment. Volume is about 125 mL. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  4. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Close-up view of the interior of a NASA Bioreactor shows the plastic plumbing and valves (cylinders at right center) to control fluid flow. The rotating wall vessel is at top center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  5. Osteocytes Mechanosensing in NASA Rotating Wall Bioreactor

    NASA Technical Reports Server (NTRS)

    Spatz, Jordan; Sibonga, Jean; Wu, Honglu; Barry, Kevin; Bouxsein, Mary; Pajevic, Paola Divieti

    2010-01-01

    Osteocyte cells are the most abundant (90%) yet least understood bone cell type in the human body. Osteocytes are theorized to be the mechanosensors and transducers of mechanical load for bones, yet the biological mechanism of this action remains elusive. However, recent discoveries in osteocyte cell biology have shed light on their importance as key mechanosensing cells regulating bone remodeling and phosphate homeostasis. The aim of this project was to characterize gene expression patterns and protein levels following exposure of MLO-Y4, a very well characterized murine osteocyte-like cell line, to simulated microgravity using the NASA Rotating Wall Vessel (RWV) Bioreactor. To determine mechanistic pathways of the osteocyte's gravity sensing ability, we evaluated in vitro gene and protein expression of osteocytes exposed to simulated microgravity. Improved understanding of the fundamental mechanisms of mechano transduction at the osteocyte cellular level may lead to revolutionary treatment otions to mitigate the effects of bone loss encountered by astronauts on long duration space missions and provide tailored treatment options for maintaining bone strength of immobilized/partially paralyzed patients here on Earth.

  6. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Exterior view of the NASA Bioreactor Engineering Development Unit flown on Mir. The rotating wall vessel is behind the window on the face of the large module. Control electronics are in the module at left; gas supply and cooling fans are in the module at back. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  7. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Close-up view of the interior of a NASA Bioreactor shows the plastic plumbing and valves (cylinders at center) to control fluid flow. A fresh nutrient bag is installed at top; a flattened waste bag behind it will fill as the nutrients are consumed during the course of operation. The drive chain and gears for the rotating wall vessel are visible at bottom center center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  8. Long term organ culture of human prostate tissue in a NASA-designed rotating wall bioreactor

    NASA Technical Reports Server (NTRS)

    Margolis, L.; Hatfill, S.; Chuaqui, R.; Vocke, C.; Emmert-Buck, M.; Linehan, W. M.; Duray, P. H.

    1999-01-01

    PURPOSE: To maintain ex vivo integral prostatic tissue including intact stromal and ductal elements using the NASA-designed Rotating Wall Vessel (RWV) which maintains colocalized cells in an environment that promotes both three-dimensional cellular interactions together with the uniform mass transfer of nutrients and metabolic wastes. MATERIALS AND METHODS: Samples of normal prostate were obtained as a byproduct of transurethral prostatectomy or needle biopsy. Prostatic tissue dissected into small 1 x 1 mm. blocks was cultured in the Rotating Wall Vessel (RWV) Bioreactor for various time periods and analyzed using histological, immunochemical, and total cell RNA assays. RESULTS: We report the long term maintenance of benign explanted human prostate tissue grown in simple culture medium, under the simulated microgravity conditions afforded by the RWV bioreactor. Mesenchymal stromal elements including blood vessels and architecturally preserved tubuloglandular acini were maintained for a minimum of 28 days. Cytokeratins, vimentin and TGF-beta2 receptor and ligand were preserved through the entire culture period as revealed by immunocytochemistry. Prostatic acid phosphatase (PAP) was continuously expressed during the culture period, although somewhat decreased. Prostatic specific antigen (PSA) and its transcript were down regulated over time of culture. Prostatic carcinoma cells from the TSU cell line were able to invade RWV-cultured benign prostate tissue explants. CONCLUSIONS: The RWV bioreactor represents an additional new technology for culturing prostate tissue for further investigations concerning the basic physiology and pathobiology of this clinically important tissue.

  9. Numerical simulation of microcarrier motion in a rotating wall vessel bioreactor.

    PubMed

    Ju, Zhi-Hao; Liu, Tian-Qing; Ma, Xue-Hu; Cui, Zhan-Feng

    2006-06-01

    To analyze the forces of rotational wall vessel (RWV) bioreactor on small tissue pieces or microcarrier particles and to determine the tracks of microcarrier particles in RWV bioreactor. The motion of the microcarrier in the rotating wall vessel (RWV) bioreactor with both the inner and outer cylinders rotating was modeled by numerical simulation. The continuous trajectory of microcarrier particles, including the possible collision with the wall was obtained. An expression between the minimum rotational speed difference of the inner and outer cylinders and the microcarrier particle or aggregate radius could avoid collisions with either wall. The range of microcarrier radius or tissue size, which could be safely cultured in the RWV bioreactor, in terms of shear stress level, was determined. The model works well in describing the trajectory of a heavier microcarrier particle in rotating wall vessel.

  10. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101825 for a version with major elements labeled, and No. 0103180 for an operational schematic. 0101816

  11. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101816 for a version without labels, and No. 0103180 for an operational schematic.

  12. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101823 for a version without labels, and No. 0103180 for an operational schematic.

  13. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101824 for a version with labels, and No. 0103180 for an operational schematic.

  14. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Electronics control module for the NASA Bioreactor. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  15. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Interior view of the gas supply for the NASA Bioreactor. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  16. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Laptop computer sits atop the Experiment Control Computer for a NASA Bioreactor. The flight crew can change operating conditions in the Bioreactor by using the graphical interface on the laptop. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  17. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Interior of a Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  18. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  19. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell and with thermal blankets partially removed. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  20. The Flow in a Model Rotating-Wall Bioreactor.

    NASA Astrophysics Data System (ADS)

    Smith, Marc K.; Neitzel, G. Paul

    1997-11-01

    Aggregates of mammalian cells can be grown on artificial polymer constructs in a reactor vessel in order to produce high-quality tissue for medical applications. The growth and differentiation of these cells is greatly affected by the fluid flow and mass transfer within the bioreactor. The surface shear stress on the constructs is an especially important quantity of interest. Here, we consider a bioreactor in the form of two concentric, independently-rotating cylinders with the axis of rotation in a horizontal plane. We shall examine the flow around a model tissue construct in the form of a disk fixed in the flow produced by the rotating walls of the bioreactor. Using CFD techniques, we shall determine the flow field and the surface shear stress distribution on the construct as a function of the wall velocities, the Reynolds number of the flow, and the construct size and position. The results will be compared to the PIV measurements of this system reported by Brown & Neitzel(1997 Meeting of the APS/DFD.).

  1. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Astronaut John Blaha replaces an exhausted media bag and filled waste bag with fresh bags to continue a bioreactor experiment aboard space station Mir in 1996. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. This image is from a video downlink. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  2. Rotating Bioreactor

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues currently being cultured in rotating bioreactors by investigators.

  3. NASA Bioreactor Demonstration System

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Leland W. K. Chung (left), Director, Molecular Urology Therapeutics Program at the Winship Cancer Institute at Emory University, is principal investigator for the NASA bioreactor demonstration system (BDS-05). With him is Dr. Jun Shu, an assistant professor of Orthopedics Surgery from Kuming Medical University China. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  4. NASA Bioreactor Schematic

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The schematic depicts the major elements and flow patterns inside the NASA Bioreactor system. Waste and fresh medium are contained in plastic bags placed side-by-side so the waste bag fills as the fresh medium bag is depleted. The compliance vessel contains a bladder to accommodate pressure transients that might damage the system. A peristolic pump moves fluid by squeezing the plastic tubing, thus avoiding potential contamination. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  5. Cells growing in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. Shown here, clusters of cells slowly spin inside a bioreactor. On Earth, the cells continually fall through the buffer medium and never hit bottom. In space, they are naturally suspended. Rotation ensures gentle stirring so waste is removed and fresh nutrient and oxygen are supplied. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  6. NASA Classroom Bioreactor

    NASA Technical Reports Server (NTRS)

    Scully, Robert

    2004-01-01

    Exploration of space provides a compelling need for cell-based research into the basic mechanisms that underlie the profound changes that occur in terrestrial life that is transitioned to low gravity environments. Toward that end, NASA developed a rotating bioreactor in which cells are cultured while continuously suspended in a cylinder in which the culture medium rotates with the cylinder. The randomization of the gravity vector accomplished by the continuous rotation, in a low shear environment, provides an analog of microgravity. Because cultures grown in bioreactors develop structures and functions that are much closer to those exhibited by native tissue than can be achieved with traditional culture methods, bioreactors have contributed substantially to advancing research in the fields of cancer, diabetes, infectious disease modeling for vaccine production, drug efficacy, and tissue engineering. NASA has developed a Classroom Bioreactor (CB) that is built from parts that are easily obtained and assembled, user-friendly and versatile. It can be easily used in simple school settings to examine the effect cultures of seeds or cells. An educational brief provides assembly instructions and lesson plans that describes activities in science, math and technology that explore free fall, microgravity, orbits, bioreactors, structure-function relationships and the scientific method.

  7. Erythroid cell growth and differentiation in vitro in the simulated microgravity environment of the NASA rotating wall vessel bioreactor

    NASA Technical Reports Server (NTRS)

    Sytkowski, A. J.; Davis, K. L.

    2001-01-01

    Prolonged exposure of humans and experimental animals to the altered gravitational conditions of space flight has adverse effects on the lymphoid and erythroid hematopoietic systems. Although some information is available regarding the cellular and molecular changes in lymphocytes exposed to microgravity, little is known about the erythroid cellular changes that may underlie the reduction in erythropoiesis and resultant anemia. We now report a reduction in erythroid growth and a profound inhibition of erythropoietin (Epo)-induced differentiation in a ground-based simulated microgravity model system. Rauscher murine erythroleukemia cells were grown either in tissue culture vessels at 1 x g or in the simulated microgravity environment of the NASA-designed rotating wall vessel (RWV) bioreactor. Logarithmic growth was observed under both conditions; however, the doubling time in simulated microgravity was only one-half of that seen at 1 x g. No difference in apoptosis was detected. Induction with Epo at the initiation of the culture resulted in differentiation of approximately 25% of the cells at 1 x g, consistent with our previous observations. In contrast, induction with Epo at the initiation of simulated microgravity resulted in only one-half of this degree of differentiation. Significantly, the growth of cells in simulated microgravity for 24 h prior to Epo induction inhibited the differentiation almost completely. The results suggest that the NASA RWV bioreactor may serve as a suitable ground-based microgravity simulator to model the cellular and molecular changes in erythroid cells observed in true microgravity.

  8. Prostate tumor grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This prostate cancer construct was grown during NASA-sponsored bioreactor studies on Earth. Cells are attached to a biodegradable plastic lattice that gives them a head start in growth. Prostate tumor cells are to be grown in a NASA-sponsored Bioreactor experiment aboard the STS-107 Research-1 mission in 2002. Dr. Leland Chung of the University of Virginia is the principal investigator. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and the University of Virginia.

  9. Colon tumor cells grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These photos compare the results of colon carcinoma cells grown in a NASA Bioreactor flown on the STS-70 Space Shuttle in 1995 flight and ground control experiments. The cells grown in microgravity (left) have aggregated to form masses that are larger and more similar to tissue found in the body than the cells cultured on the ground (right). The principal investigator is Milburn Jessup of the University of Texas M. D. Anderson Cancer Center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: NASA and University of Texas M. D. Anderson Cancer Center.

  10. Shear stress enhances microcin B17 production in a rotating wall bioreactor, but ethanol stress does not

    NASA Technical Reports Server (NTRS)

    Gao, Q.; Fang, A.; Pierson, D. L.; Mishra, S. K.; Demain, A. L.

    2001-01-01

    Stress, including that caused by ethanol, has been shown to induce or promote secondary metabolism in a number of microbial systems. Rotating-wall bioreactors provide a low stress and simulated microgravity environment which, however, supports only poor production of microcin B17 by Escherichia coli ZK650, as compared to production in agitated flasks. We wondered whether the poor production is due to the low level of stress and whether increasing stress in the bioreactors would raise the amount of microcin B17 formed. We found that applying shear stress by addition of a single Teflon bead to a rotating wall bioreactor improved microcin B17 production. By contrast, addition of various concentrations of ethanol to such bioreactors (or to shaken flasks) failed to increase microcin B17 production. Ethanol stress merely decreased production and, at higher concentrations, inhibited growth. Interestingly, cells growing in the bioreactor were much more resistant to the growth-inhibitory and production-inhibitory effects of ethanol than cells growing in shaken flasks.

  11. Heart tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Lisa Freed and Gordana Vunjak-Novakovic, both of the Massachusetts Institute of Technology (MIT), have taken the first steps toward engineering heart muscle tissue that could one day be used to patch damaged human hearts. Cells isolated from very young animals are attached to a three-dimensional polymer scaffold, then placed in a NASA bioreactor. The cells do not divide, but after about a week start to cornect to form a functional piece of tissue. Functionally connected heart cells that are capable of transmitting electrical signals are the goal for Freed and Vunjak-Novakovic. Electrophysiological recordings of engineered tissue show spontaneous contractions at a rate of 70 beats per minute (a), and paced contractions at rates of 80, 150, and 200 beats per minute respectively (b, c, and d). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: NASA and MIT.

  12. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 deg. C (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  13. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 degreesC (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  14. Heart tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Lisa Freed and Gordana Vunjak-Novakovic, both of the Massachusetts Institute of Technology (MIT), have taken the first steps toward engineering heart muscle tissue that could one day be used to patch damaged human hearts. Cells isolated from very young animals are attached to a three-dimensional polymer scaffold, then placed in a NASA bioreactor. The cells do not divide, but after about a week start to cornect to form a functional piece of tissue. Here, a transmission electron micrograph of engineered tissue shows a number of important landmarks present in functional heart tissue: (A) well-organized myofilaments (Mfl), z-lines (Z), and abundant glycogen granules (Gly); and (D) intercalcated disc (ID) and desmosomes (DES). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: MIT

  15. Growth of Streptomyces Hygroscopicus in Rotating-Wall Bioreactor Under Simulated Microgravity Inhibits Rapamycin Production

    NASA Technical Reports Server (NTRS)

    Fang, A.; Pierson, D. L.; Mishra, S. K.; Demain, A. L.

    2000-01-01

    Growth of Streptomyces hygroscopicus under conditions of simulated microgravity in a rotating-wall bioreactor resulted in a pellet form of growth, lowered dry cell weight, and inhibition of rapamycin production. With the addition of Teflon beads to the bioreactor, growth became much less pelleted, dry cell weight increased but rapamycin production was still markedly inhibited. Growth under simulated microgravity favored extracellular production of rapamycin in contrast to a greater percentage of cell-bound rapamycin observed under normal gravity conditions.

  16. Growth of Steptomyces hygroscopicus in rotating-wall bioreactor under simulated microgravity inhibits rapamycin production

    NASA Technical Reports Server (NTRS)

    Fang, A.; Pierson, D. L.; Mishra, S. K.; Demain, A. L.

    2000-01-01

    Growth of Streptomyces hygroscopicus under conditions of simulated microgravity in a rotating-wall bioreactor resulted in a pellet form of growth, lowered dry cell weight, and inhibition of rapamycin production. With the addition of Teflon beads to the bioreactor, growth became much less pelleted, dry cell weight increased but rapamycin production was still markedly inhibited. Growth under simulated microgravity favored extracellular production of rapamycin, in contrast to a greater percentage of cell-bound rapamycin observed under normal gravity conditions.

  17. JSC technician checks STS-44 DSO 316 bioreactor and rotating wall vessel hdwr

    NASA Image and Video Library

    1991-06-27

    S91-40049 (27 June 1991) --- JSC technician Tacey Prewitt checks the progress on a bioreactor experiment in JSC's Life Sciences Laboratory Bldg 37 biotechnology laboratory. Similar hardware is scheduled for testing aboard Atlantis, Orbiter Vehicle (OV) 104, during STS-44. Detailed Supplementary Objective (DSO) 316 Bioreactor/Flow and Particle Trajectory in Microgravity will checkout the rotating wall vessel hardware and hopefully will confirm researchers' theories and calculations about how flow fields work in space. Plastic beads of various sizes rather than cell cultures are being flown in the vessel for the STS-44 test.

  18. JSC technician checks STS-44 DSO 316 bioreactor and rotating wall vessel hdwr

    NASA Technical Reports Server (NTRS)

    1991-01-01

    JSC technician Tacey Prewitt checks the progress on a bioreactor experiment in JSC's Life Sciences Laboratory Bldg 37 biotechnology laboratory. Similar hardware is scheduled for testing aboard Atlantis, Orbiter Vehicle (OV) 104, during STS-44. Detailed Supplementary Objective (DSO) 316 Bioreactor/Flow and Particle Trajectory in Microgravity will checkout the rotating wall vessel hardware and hopefully will confirm researchers' theories and calculations about how flow fields work in space. Plastic beads of various sizes rather than cell cultures are being flown in the vessel for the STS-44 test.

  19. NASA Bioreactor tissue culture

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  20. Relief from glucose interference in microcin B17 biosynthesis by growth in a rotating-wall bioreactor

    NASA Technical Reports Server (NTRS)

    Fang, A.; Pierson, D. L.; Mishra, S. K.; Demain, A. L.; Peirson, D. L. (Principal Investigator)

    2000-01-01

    Glucose interference in production of microcin B17 by Escherichia coli ZK650 was decreased sevenfold by growth in a ground-based rotating-wall bioreactor operated in the simulated microgravity mode as compared with growth in flasks. When cells were grown in the bioreactor in the normal gravity mode, relief from glucose interference was even more dramatic, amounting to a decrease in glucose interference of over 100-fold.

  1. Tissue grown in space in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, such as the culture section shown here, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. The two white circles within the tumor are part of a plastic lattice that helped the cells associate. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  2. NASA Bioreactors Advance Disease Treatments

    NASA Technical Reports Server (NTRS)

    2009-01-01

    The International Space Station (ISS) is falling. This is no threat to the astronauts onboard, however, because falling is part of the ISS staying in orbit. The absence of gravity beyond the Earth s atmosphere is actually an illusion; at the ISS s orbital altitude of approximately 250 miles above the surface, the planet s gravitational pull is only 12-percent weaker than on the ground. Gravity is constantly pulling the ISS back to Earth, but the space station is also constantly traveling at nearly 18,000 miles per hour. This means that, even though the ISS is falling toward Earth, it is moving sideways fast enough to continually miss impacting the planet. The balance between the force of gravity and the ISS s motion creates a stable orbit, and the fact that the ISS and everything in it including the astronauts are falling at an equal rate creates the condition of weightlessness called microgravity. The constant falling of objects in orbit is not only an important principle in space, but it is also a key element of a revolutionary NASA technology here on Earth that may soon help cure medical ailments from heart disease to diabetes. In the mid-1980s, NASA researchers at Johnson Space Center were investigating the effects of long-term microgravity on human tissues. At the time, the Agency s shuttle fleet was grounded following the 1986 Space Shuttle Challenger disaster, and researchers had no access to the microgravity conditions of space. To provide a method for recreating such conditions on Earth, Johnson s David Wolf, Tinh Trinh, and Ray Schwarz developed that same year a horizontal, rotating device called a rotating wall bioreactor that allowed the growth of human cells in simulated weightlessness. Previously, cell cultures on Earth could only be grown two-dimensionally in Petri dishes, because gravity would cause the multiplying cells to sink within their growth medium. These cells do not look or function like real human cells, which grow three-dimensionally in

  3. Effect of Rotation on Scaffold Motion and Cell Growth in Rotating Bioreactors.

    PubMed

    Varley, Mark C; Markaki, Athina E; Brooks, Roger A

    2017-06-01

    Efficient use of different bioreactor designs to improve cell growth in three-dimensional scaffolds requires an understanding of their mechanism of action. To address this for rotating wall vessel bioreactors, fluid and scaffold motion were investigated experimentally at different rotation speeds and vessel fill volumes. Low cost bioreactors with single and dual axis rotation were developed to investigate the effect of these systems on human osteoblast proliferation in free floating and constrained collagen-glycosaminoglycan porous scaffolds. A range of scaffold motions (free fall, periodic oscillation, and orbital motion) were observed at the rotation speeds and vessel fluid/air ratios used, with 85% fluid fill and an outer vessel wall velocity of ∼14 mm s -1 producing a scaffold in a free fall state. The cell proliferation results showed that after 14 and 21 days of culture, this combination of fluid fill and speed of rotation produced significantly greater cell numbers in the scaffolds than when lower or higher rotation speeds (p < 0.002) or when the chamber was 60% or 100% full (p < 0.01). The fluid flow and scaffold motion experiments show that biaxial rotation would not improve the mass transfer of medium into the scaffold as the second axis of rotation can only transition the scaffold toward oscillatory or orbital motion and, hence, reduce mass transport to the scaffold. The cell culture results confirmed that there was no benefit to the second axis of rotation with no significant difference in cell proliferation either when the scaffolds were free floating or constrained (p > 0.05).

  4. Effect of Rotation on Scaffold Motion and Cell Growth in Rotating Bioreactors

    PubMed Central

    Varley, Mark C.; Markaki, Athina E.

    2017-01-01

    Efficient use of different bioreactor designs to improve cell growth in three-dimensional scaffolds requires an understanding of their mechanism of action. To address this for rotating wall vessel bioreactors, fluid and scaffold motion were investigated experimentally at different rotation speeds and vessel fill volumes. Low cost bioreactors with single and dual axis rotation were developed to investigate the effect of these systems on human osteoblast proliferation in free floating and constrained collagen-glycosaminoglycan porous scaffolds. A range of scaffold motions (free fall, periodic oscillation, and orbital motion) were observed at the rotation speeds and vessel fluid/air ratios used, with 85% fluid fill and an outer vessel wall velocity of ∼14 mm s−1 producing a scaffold in a free fall state. The cell proliferation results showed that after 14 and 21 days of culture, this combination of fluid fill and speed of rotation produced significantly greater cell numbers in the scaffolds than when lower or higher rotation speeds (p < 0.002) or when the chamber was 60% or 100% full (p < 0.01). The fluid flow and scaffold motion experiments show that biaxial rotation would not improve the mass transfer of medium into the scaffold as the second axis of rotation can only transition the scaffold toward oscillatory or orbital motion and, hence, reduce mass transport to the scaffold. The cell culture results confirmed that there was no benefit to the second axis of rotation with no significant difference in cell proliferation either when the scaffolds were free floating or constrained (p > 0.05). PMID:28125920

  5. Tissue grown in space in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens of cartilage tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. Constructs grown on Mir (A) tended to become more spherical, whereas those grown on Earth (B) maintained their initial disc shape. These findings might be related to differences in cultivation conditions, i.e., videotapes showed that constructs floated freely in microgravity but settled and collided with the rotating vessel wall at 1g (Earth's gravity). In particular, on Mir the constructs were exposed to uniform shear and mass transfer at all surfaces such that the tissue grew equally in all directions, whereas on Earth the settling of discoid constructs tended to align their flat circular areas perpendicular to the direction of motion, increasing shear and mass transfer circumferentially such that the tissue grew preferentially in the radial direction. A and B are full cross sections of constructs from Mir and Earth groups shown at 10-power. C and D are representative areas at the construct surfaces enlarged to 200-power. They are stained red with safranin-O. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Photo credit: Proceedings of the National Academy of Sciences.

  6. Optimal 3D culture of primary articular chondrocytes for use in the rotating wall vessel bioreactor.

    PubMed

    Mellor, Liliana F; Baker, Travis L; Brown, Raquel J; Catlin, Lindsey W; Oxford, Julia Thom

    2014-08-01

    Reliable culturing methods for primary articular chondrocytes are essential to study the effects of loading and unloading on joint tissue at the cellular level. Due to the limited proliferation capacity of primary chondrocytes and their tendency to dedifferentiate in conventional culture conditions, long-term culturing conditions of primary chondrocytes can be challenging. The goal of this study was to develop a suspension culturing technique that not only would retain the cellular morphology, but also maintain the gene expression characteristics of primary articular chondrocytes. Three-dimensional culturing methods were compared and optimized for primary articular chondrocytes in the rotating wall vessel bioreactor, which changes the mechanical culture conditions to provide a form of suspension culture optimized for low shear and turbulence. We performed gene expression analysis and morphological characterization of cells cultured in alginate beads, Cytopore-2 microcarriers, primary monolayer culture, and passaged monolayer cultures using reverse transcription-PCR and laser scanning confocal microscopy. Primary chondrocytes grown on Cytopore-2 microcarriers maintained the phenotypical morphology and gene expression pattern observed in primary bovine articular chondrocytes, and retained these characteristics for up to 9 d. Our results provide a novel and alternative culturing technique for primary chondrocytes suitable for studies that require suspension such as those using the rotating wall vessel bioreactor. In addition, we provide an alternative culturing technique for primary chondrocytes that can impact future mechanistic studies of osteoarthritis progression, treatments for cartilage damage and repair, and cartilage tissue engineering.

  7. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Time-lapse exposure depicts Bioreactor rotation. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues.

  8. Bioreactor principles

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Cells cultured on Earth (left) typically settle quickly on the bottom of culture vessels due to gravity. In microgravity (right), cells remain suspended and aggregate to form three-dimensional tissue. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  9. Accelerated and Improved Differentiation of Retinal Organoids from Pluripotent Stem Cells in Rotating-Wall Vessel Bioreactors.

    PubMed

    DiStefano, Tyler; Chen, Holly Yu; Panebianco, Christopher; Kaya, Koray Dogan; Brooks, Matthew J; Gieser, Linn; Morgan, Nicole Y; Pohida, Tom; Swaroop, Anand

    2018-01-09

    Pluripotent stem cells can be differentiated into 3D retinal organoids, with major cell types self-patterning into a polarized, laminated architecture. In static cultures, organoid development may be hindered by limitations in diffusion of oxygen and nutrients. Herein, we report a bioprocess using rotating-wall vessel (RWV) bioreactors to culture retinal organoids derived from mouse pluripotent stem cells. Organoids in RWV demonstrate enhanced proliferation, with well-defined morphology and improved differentiation of neurons including ganglion cells and S-cone photoreceptors. Furthermore, RWV organoids at day 25 (D25) reveal similar maturation and transcriptome profile as those at D32 in static culture, closely recapitulating spatiotemporal development of postnatal day 6 mouse retina in vivo. Interestingly, however, retinal organoids do not differentiate further under any in vitro condition tested here, suggesting additional requirements for functional maturation. Our studies demonstrate that bioreactors can accelerate and improve organoid growth and differentiation for modeling retinal disease and evaluation of therapies. Published by Elsevier Inc.

  10. Culturing and applications of rotating wall vessel bioreactor derived 3D epithelial cell models.

    PubMed

    Radtke, Andrea L; Herbst-Kralovetz, Melissa M

    2012-04-03

    Cells and tissues in the body experience environmental conditions that influence their architecture, intercellular communications, and overall functions. For in vitro cell culture models to accurately mimic the tissue of interest, the growth environment of the culture is a critical aspect to consider. Commonly used conventional cell culture systems propagate epithelial cells on flat two-dimensional (2-D) impermeable surfaces. Although much has been learned from conventional cell culture systems, many findings are not reproducible in human clinical trials or tissue explants, potentially as a result of the lack of a physiologically relevant microenvironment. Here, we describe a culture system that overcomes many of the culture condition boundaries of 2-D cell cultures, by using the innovative rotating wall vessel (RWV) bioreactor technology. We and others have shown that organotypic RWV-derived models can recapitulate structure, function, and authentic human responses to external stimuli similarly to human explant tissues (1-6). The RWV bioreactor is a suspension culture system that allows for the growth of epithelial cells under low physiological fluid shear conditions. The bioreactors come in two different formats, a high-aspect rotating vessel (HARV) or a slow-turning lateral vessel (STLV), in which they differ by their aeration source. Epithelial cells are added to the bioreactor of choice in combination with porous, collagen-coated microcarrier beads (Figure 1A). The cells utilize the beads as a growth scaffold during the constant free fall in the bioreactor (Figure 1B). The microenvironment provided by the bioreactor allows the cells to form three-dimensional (3-D) aggregates displaying in vivo-like characteristics often not observed under standard 2-D culture conditions (Figure 1D). These characteristics include tight junctions, mucus production, apical/basal orientation, in vivo protein localization, and additional epithelial cell-type specific properties

  11. Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues currently being cultured in rotating bioreactors by investigators

  12. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Human primary breast tumor cells after 49 days of growth in a NASA Bioreactor. Tumor cells aggregate on microcarrier beads (indicated by arrow). NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Jearne Becker, University of South Florida

  13. Tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Cells from kidneys lose some of their special features in conventional culture but form spheres replete with specialized cell microvilli (hair) and synthesize hormones that may be clinically useful. Ground-based research studies have demonstrated that both normal and neoplastic cells and tissues recreate many of the characteristics in the NASA bioreactor that they display in vivo. Proximal kidney tubule cells that normally have rich apically oriented microvilli with intercellular clefts in the kidney do not form any of these structures in conventional two-dimensional monolayer culture. However, when normal proximal renal tubule cells are cultured in three-dimensions in the bioreactor, both the microvilli and the intercellular clefts form. This is important because, when the morphology is recreated, the function is more likely also to be rejuvenated. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  14. Visualization and Measurement of Flow in a Model Rotating-Wall Bioreactor

    NASA Astrophysics Data System (ADS)

    Brown, Jason B.; Neitzel, G. Paul

    1997-11-01

    Fluid shear has been observed to have an effect on the in vitro growth of mammalian cells and is expected to play a role in the in vitro development of aggregates of cells into tissue. The interactions between culture media and cell constructs within a circular Couette flow bioreactor with independently rotating cylinders are investigated in model studies using flow visualization. Particle-Image Velocimetry (PIV) is used to quantify the velocity field in a plane perpendicular to the vessel axis which contains a cell construct model. This velocity field is then used to compute the instantaneous shear field. Experiments show the path of the model cell construct is dependent on the rotation rates of the cylinders.

  15. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Dr. Harry Mahtani analyzes the gas content of nutrient media from Bioreactor used in research on human breast cancer. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues.

  16. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    High magnification view of human primary breast tumor cells after 56 days of culture in a NASA Bioreactor. The arrow points to bead surface indicating breast cancer cells (as noted by the staining of tumor cell intermediate filaments). NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Jearne Becker, University of South Florida

  17. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    High magnification of view of tumor cells aggregate on microcarrier beads, illustrting breast cells with intercellular boundaires on bead surface and aggregates of cells achieving 3-deminstional growth outward from bead after 56 days of culture in a NASA Bioreactor. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Jearne Becker, University of South Florida.

  18. Removal of Cr, Mn, and Co from textile wastewater by horizontal rotating tubular bioreactor.

    PubMed

    Zeiner, Michaela; Rezić, Tonci; Santek, Bozidar; Rezić, Iva; Hann, Stephan; Stingeder, Gerhard

    2012-10-02

    Environmental pollution by industrial wastewaters polluted with toxic heavy metals is of great concern. Various guidelines regulate the quality of water released from industrial plants and of surface waters. In wastewater treatment, bioreactors with microbial biofilms are widely used. A horizontal rotating tubular bioreactor (HRTB) is a combination of a thin layer and a biodisc reactor with an interior divided by O-ring shaped partition walls as carriers for microbial biomass. Using a biofilm of heavy metal resistant bacteria in combination with this special design provides various advantages for wastewater treatment proven in a pilot study. In the presented study, the applicability of HRTB for removing metals commonly present in textile wastewaters (chromium, manganese, cobalt) was investigated. Artificial wastewaters with a load of 125 mg/L of each metal underwent the bioreactor treatment. Different process parameters (inflow rate, rotation speed) were applied for optimizing the removal efficiency. Samples were drawn along the bioreactor length for monitoring the metal contents on site by UV-vis spectrometry. The metal uptake of the biomass was determined by ICP-MS after acidic microwave assisted digestion. The maximum removal rates obtained for chromium, manganese, and cobalt were: 100%, 94%, and 69%, respectively.

  19. Formation of three-dimensional cell/polymer constructs for bone tissue engineering in a spinner flask and a rotating wall vessel bioreactor

    NASA Technical Reports Server (NTRS)

    Sikavitsas, Vassilios I.; Bancroft, Gregory N.; Mikos, Antonios G.; McIntire, L. V. (Principal Investigator)

    2002-01-01

    The aim of this study is to investigate the effect of the cell culture conditions of three-dimensional polymer scaffolds seeded with rat marrow stromal cells (MSCs) cultured in different bioreactors concerning the ability of these cells to proliferate, differentiate towards the osteoblastic lineage, and generate mineralized extracellular matrix. MSCs harvested from male Sprague-Dawley rats were culture expanded, seeded on three-dimensional porous 75:25 poly(D,L-lactic-co-glycolic acid) biodegradable scaffolds, and cultured for 21 days under static conditions or in two model bioreactors (a spinner flask and a rotating wall vessel) that enhance mixing of the media and provide better nutrient transport to the seeded cells. The spinner flask culture demonstrated a 60% enhanced proliferation at the end of the first week when compared to static culture. On day 14, all cell/polymer constructs exhibited their maximum alkaline phosphatase activity (AP). Cell/polymer constructs cultured in the spinner flask had 2.4 times higher AP activity than constructs cultured under static conditions on day 14. The total osteocalcin (OC) secretion in the spinner flask culture was 3.5 times higher than the static culture, with a peak OC secretion occurring on day 18. No considerable AP activity and OC secretion were detected in the rotating wall vessel culture throughout the 21-day culture period. The spinner flask culture had the highest calcium content at day 14. On day 21, the calcium deposition in the spinner flask culture was 6.6 times higher than the static cultured constructs and over 30 times higher than the rotating wall vessel culture. Histological sections showed concentration of cells and mineralization at the exterior of the foams at day 21. This phenomenon may arise from the potential existence of nutrient concentration gradients at the interior of the scaffolds. The better mixing provided in the spinner flask, external to the outer surface of the scaffolds, may explain the

  20. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Human primary breast tumor cells after 56 days of culture in a NASA Bioreactor. A cross-section of a construct, grown from surgical specimens of brease cancer, stained for microscopic examination, reveals areas of tumor cells dispersed throughout the non-epithelial cell background. The arrow denotes the foci of breast cancer cells. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Jearne Becker, University of South Florida

  1. The Fluid Mechanics of a Wavy-Wall Bioreactor

    NASA Astrophysics Data System (ADS)

    Sucosky, Philippe; Bilgen, Bahar; Aleem, Alexander; Neitzel, Paul; Barabino, Gilda

    2004-11-01

    Bioreactors are devices used for the production of mammalian tissue in vitro. Although mixing has been shown to stimulate the growth of cartilage constructs, high shear-stress levels can damage the cells. In order to enhance mixing while minimizing shear, a wavy-wall bioreactor (WWB) featuring a sinusoidal internal profile has been designed. The turbulent hydrodynamic environment produced in this device is investigated experimentally using particle-image velocimetry. A model bioreactor made of acrylic and filled with an index-matching solution of zinc iodide is used to compensate for the refraction of light at the walls. The flow observed in different planes is shown to be periodic, spatially dependent, and dominated by mean-shear rather than Reynolds stresses in the vicinity of constructs. Finally, a comparison between the mean-shear stresses obtained in the WWB and in a standard spinner flask reveals similar stress levels near the construct walls.

  2. Three-Dimensional Rotating Wall Vessel-Derived Cell Culture Models for Studying Virus-Host Interactions

    PubMed Central

    Gardner, Jameson K.; Herbst-Kralovetz, Melissa M.

    2016-01-01

    The key to better understanding complex virus-host interactions is the utilization of robust three-dimensional (3D) human cell cultures that effectively recapitulate native tissue architecture and model the microenvironment. A lack of physiologically-relevant animal models for many viruses has limited the elucidation of factors that influence viral pathogenesis and of complex host immune mechanisms. Conventional monolayer cell cultures may support viral infection, but are unable to form the tissue structures and complex microenvironments that mimic host physiology and, therefore, limiting their translational utility. The rotating wall vessel (RWV) bioreactor was designed by the National Aeronautics and Space Administration (NASA) to model microgravity and was later found to more accurately reproduce features of human tissue in vivo. Cells grown in RWV bioreactors develop in a low fluid-shear environment, which enables cells to form complex 3D tissue-like aggregates. A wide variety of human tissues (from neuronal to vaginal tissue) have been grown in RWV bioreactors and have been shown to support productive viral infection and physiological meaningful host responses. The in vivo-like characteristics and cellular features of the human 3D RWV-derived aggregates make them ideal model systems to effectively recapitulate pathophysiology and host responses necessary to conduct rigorous basic science, preclinical and translational studies. PMID:27834891

  3. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Breast tissue specimens in traditional sample dishes. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues.

  4. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Dr. Robert Richmond extracts breast cell tissue from one of two liquid nitrogen dewars. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues.

  5. Rotating bio-reactor cell culture apparatus

    NASA Technical Reports Server (NTRS)

    Schwarz, Ray P. (Inventor); Wolf, David A. (Inventor)

    1991-01-01

    A bioreactor system is described in which a tubular housing contains an internal circularly disposed set of blade members and a central tubular filter all mounted for rotation about a common horizontal axis and each having independent rotational support and rotational drive mechanisms. The housing, blade members and filter preferably are driven at a constant slow speed for placing a fluid culture medium with discrete microbeads and cell cultures in a discrete spatial suspension in the housing. Replacement fluid medium is symmetrically input and fluid medium is symmetrically output from the housing where the input and the output are part of a loop providing a constant or intermittent flow of fluid medium in a closed loop.

  6. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Isolation of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Isolate of long-term growth human mammary epithelial cells (HMEC) from outgrowth of duct element; cells shown soon after isolation and early in culture in a dish. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Tichmond, NASA/Marshall Space Flight Center (MSFC).

  7. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues. Here, two High-Aspect Ratio Vessels turn at about 12 rmp to keep breast tissue constructs suspended inside the culture media. Syringes allow scientists to pull for analysis during growth sequences. The tube in the center is a water bubbler that dehumidifies the air to prevent evaporation of the media and thus the appearance of destructive bubbles in the bioreactor.

  8. Enhancement of matrix production and cell proliferation in human annulus cells under bioreactor culture.

    PubMed

    Yang, Xinlin; Wang, Daidong; Hao, Jianrong; Gong, Meiqing; Arlet, Vincent; Balian, Gary; Shen, Francis H; Li, Xudong Joshua

    2011-06-01

    Tissue engineering is a promising approach for treatment of disc degeneration. Herein, we evaluated effects of rotating bioreactor culture on the extracellular matrix production and proliferation of human annulus fibrosus (AF) cells. AF cells were embedded into alginate beads, and then cultured up to 3 weeks in a rotating wall vessel bioreactor or a static vessel. By real-time reverse transcription-polymerase chain reaction, expression of aggrecan, collagen type I and type II, and collagen prolyl 4-hydroxylase II was remarkably elevated, whereas expression of matrix metalloproteinase 3 and a disintegrin and metalloproteinase with thrombospondin motifs 5 was significantly decreased under bioreactor. Biochemical analysis revealed that the levels of the whole cell-associated proteoglycan and collagen were approximately five- and twofolds in rotating bioreactor, respectively, compared to those in static culture. Moreover, AF cell proliferation was augmented in rotating bioreactor. DNA contents were threefolds higher in rotating bioreactor than that in static culture. Expression of the proliferating cell nuclear antigen was robustly enhanced in rotating bioreactor as early as 1 week. Our findings suggested that rotating bioreactor culture would be an effective technique for expansion of human annulus cells for tissue engineering driven treatment of disc degeneration.

  9. Tissue grown in space in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. Final samples from Mir and Earth appeared histologically cartilaginous throughout their entire cross sections (5-8 mm thick), with the exception of fibrous outer capsules. Constructs grown on Earth (A) appeared to have a more organized extracellular matrix with more uniform collagen orientation as compared with constructs grown on Mir (B), but the average collagen fiber diameter was similar in the two groups (22 +- 2 nm) and comparable to that previously reported for developing articular cartilage. Randomly oriented collagen in Mir samples would be consistent with previous reports that microgravity disrupts fibrillogenesis. These are transmission electron micrographs of constructs from Mir (A) and Earth (B) groups at magnifications of x3,500 and x120,000 (Inset). The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Credit: Proceedings of the National Academy of Sciences.

  10. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Isolation of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Outgrowth of cells from duct element in upper right corner cultured in a standard dish; most cells spontaneously die during early cell divisions, but a few will establish long-term growth. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Tichmond, NASA/Marshall Space Flight Center (MSFC).

  11. Method for culturing mammalian cells in a horizontally rotated bioreactor

    NASA Technical Reports Server (NTRS)

    Schwarz, Ray P. (Inventor); Wolf, David A. (Inventor); Trinh, Tinh T. (Inventor)

    1992-01-01

    A bio-reactor system where cell growth microcarrier beads are suspended in a zero head space fluid medium by rotation about a horizontal axis and where the fluid is continuously oxygenated from a tubular membrane which rotates on a shaft together with rotation of the culture vessel. The oxygen is continuously throughput through the membrane and disbursed into the fluid medium along the length of the membrane.

  12. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Epithelial and fibroblast cell coculture: Long-term growth human mammary epithelial cells (HMEC) admixed in coculture with fibroblast from the same initial breast tissue grown as 3-dimenstional constructions in the presence of attachment beads in the NASA Bioreactor. A: A typical constrct about 2.0 mm in diameter without beads on the surface. The center of these constrcts is hollow, and beads are organized about the irner surface. Although the coculture provides smaller constructs than the monoculture, the metabolic of the organized cells is about the same. B, C, D: Closer views of cells showing that the shape of cells and cell-to-cell interactions apprear different in the coculture than in the monoculture constructs. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Richmond, NASA/Marshall Space Flight Center (MSFC).

  13. Growing Three-Dimensional Corneal Tissue in a Bioreactor

    NASA Technical Reports Server (NTRS)

    Spaulding, Glen F.; Goodwin, Thomas J.; Aten, Laurie; Prewett, Tacey; Fitzgerald, Wendy S.; OConnor, Kim; Caldwell, Delmar; Francis, Karen M.

    2003-01-01

    Spheroids of corneal tissue about 5 mm in diameter have been grown in a bioreactor from an in vitro culture of primary rabbit corneal cells to illustrate the production of optic cells from aggregates and tissue. In comparison with corneal tissues previously grown in vitro by other techniques, this tissue approximates intact corneal tissue more closely in both size and structure. This novel three-dimensional tissue can be used to model cell structures and functions in normal and abnormal corneas. Efforts continue to refine the present in vitro method into one for producing human corneal tissue to overcome the chronic shortage of donors for corneal transplants: The method would be used to prepare corneal tissues, either from in vitro cultures of a patient s own cells or from a well-defined culture from another human donor known to be healthy. As explained in several articles in prior issues of NASA Tech Briefs, generally cylindrical horizontal rotating bioreactors have been developed to provide nutrient-solution environments conducive to the 30 NASA Tech Briefs, October 2003 growth of delicate animal cells, with gentle, low-shear flow conditions that keep the cells in suspension without damaging them. The horizontal rotating bioreactor used in this method, denoted by the acronym "HARV," was described in "High-Aspect-Ratio Rotating Cell-Culture Vessel" (MSC-21662), NASA Tech Briefs, Vol. 16, No. 5 (May, 1992), page 150.

  14. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Isolation of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Same long-term growth human mammary epithelial cells (HMEC), but after 3 weeks in concinuous culture. Note attempts to reform duct elements, but this time in two dimensions in a dish rather that in three demensions in tissue. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Tichmond, NASA/Marshall Space Flight Center (MSFC).

  15. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Epithelial cell monoculture: Long-term growth of human mammary epithelial cells (HMEC) grown in monoculture as 3-dimensional constructions in the presence of attachment beads in the NASA Bioreactor. A: A typical construct about 3.5 mm (less than 1/8th inch) in diameter with slightly dehydrted, crinkled beads contained on the surface as well as within the 3-dimensional structure. B: The center of these constructs is hollow. Crinkling of the beads causes a few to fall out, leaving crater-like impressiions in the construct. The central impression shows a small hole that accesses the hollow center of the construct. C: A closeup view of the cells and the hole the central impression. D: Closer views of cells in the construct showing sell-to-cell interactions. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Richmond, NASA/Marshall Space Flight Center (MSFC).

  16. Biomimetic fetal rotation bioreactor for engineering bone tissues-Effect of cyclic strains on upregulation of osteogenic gene expression.

    PubMed

    Ravichandran, Akhilandeshwari; Wen, Feng; Lim, Jing; Chong, Mark Seow Khoon; Chan, Jerry K Y; Teoh, Swee-Hin

    2018-04-01

    Cells respond to physiological mechanical stresses especially during early fetal development. Adopting a biomimetic approach, it is necessary to develop bioreactor systems to explore the effects of physiologically relevant mechanical strains and shear stresses for functional tissue growth and development. This study introduces a multimodal bioreactor system that allows application of cyclic compressive strains on premature bone grafts that are cultured under biaxial rotation (chamber rotation about 2 axes) conditions for bone tissue engineering. The bioreactor is integrated with sensors for dissolved oxygen levels and pH that allow real-time, non-invasive monitoring of the culture parameters. Mesenchymal stem cells-seeded polycaprolactone-β-tricalcium phosphate scaffolds were cultured in this bioreactor over 2 weeks in 4 different modes-static, cyclic compression, biaxial rotation, and multimodal (combination of cyclic compression and biaxial rotation). The multimodal culture resulted in 1.8-fold higher cellular proliferation in comparison with the static controls within the first week. Two weeks of culture in the multimodal bioreactor utilizing the combined effects of optimal fluid flow conditions and cyclic compression led to the upregulation of osteogenic genes alkaline phosphatase (3.2-fold), osteonectin (2.4-fold), osteocalcin (10-fold), and collagen type 1 α1 (2-fold) in comparison with static cultures. We report for the first time, the independent and combined effects of mechanical stimulation and biaxial rotation for bone tissue engineering using a bioreactor platform with non-invasive sensing modalities. The demonstrated results show leaning towards the futuristic vision of using a physiologically relevant bioreactor system for generation of autologous bone grafts for clinical implantation. Copyright © 2018 John Wiley & Sons, Ltd.

  17. RWPV bioreactor mass transport: earth-based and in microgravity

    NASA Technical Reports Server (NTRS)

    Begley, Cynthia M.; Kleis, Stanley J.

    2002-01-01

    Mass transport and mixing of perfused scalar quantities in the NASA Rotating Wall Perfused Vessel bioreactor are studied using numerical models of the flow field and scalar concentration field. Operating conditions typical of both microgravity and ground-based cell cultures are studied to determine the expected vessel performance for both flight and ground-based control experiments. Results are presented for the transport of oxygen with cell densities and consumption rates typical of colon cancer cells cultured in the RWPV. The transport and mixing characteristics are first investigated with a step change in the perfusion inlet concentration by computing the time histories of the time to exceed 10% inlet concentration. The effects of a uniform cell utilization rate are then investigated with time histories of the outlet concentration, volume average concentration, and volume fraction starved. It is found that the operating conditions used in microgravity produce results that are quite different then those for ground-based conditions. Mixing times for microgravity conditions are significantly shorter than those for ground-based operation. Increasing the differential rotation rates (microgravity) increases the mixing and transport, while increasing the mean rotation rate (ground-based) suppresses both. Increasing perfusion rates enhances mass transport for both microgravity and ground-based cases, however, for the present range of operating conditions, above 5-10 cc/min there are diminishing returns as much of the inlet fluid is transported directly to the perfusion exit. The results show that exit concentration is not a good indicator of the concentration distributions in the vessel. In microgravity conditions, the NASA RWPV bioreactor with the viscous pump has been shown to provide an environment that is well mixed. Even when operated near the theoretical minimum perfusion rates, only a small fraction of the volume provides less than the required oxygen levels

  18. RWPV bioreactor mass transport: earth-based and in microgravity.

    PubMed

    Begley, Cynthia M; Kleis, Stanley J

    2002-11-20

    Mass transport and mixing of perfused scalar quantities in the NASA Rotating Wall Perfused Vessel bioreactor are studied using numerical models of the flow field and scalar concentration field. Operating conditions typical of both microgravity and ground-based cell cultures are studied to determine the expected vessel performance for both flight and ground-based control experiments. Results are presented for the transport of oxygen with cell densities and consumption rates typical of colon cancer cells cultured in the RWPV. The transport and mixing characteristics are first investigated with a step change in the perfusion inlet concentration by computing the time histories of the time to exceed 10% inlet concentration. The effects of a uniform cell utilization rate are then investigated with time histories of the outlet concentration, volume average concentration, and volume fraction starved. It is found that the operating conditions used in microgravity produce results that are quite different then those for ground-based conditions. Mixing times for microgravity conditions are significantly shorter than those for ground-based operation. Increasing the differential rotation rates (microgravity) increases the mixing and transport, while increasing the mean rotation rate (ground-based) suppresses both. Increasing perfusion rates enhances mass transport for both microgravity and ground-based cases, however, for the present range of operating conditions, above 5-10 cc/min there are diminishing returns as much of the inlet fluid is transported directly to the perfusion exit. The results show that exit concentration is not a good indicator of the concentration distributions in the vessel. In microgravity conditions, the NASA RWPV bioreactor with the viscous pump has been shown to provide an environment that is well mixed. Even when operated near the theoretical minimum perfusion rates, only a small fraction of the volume provides less than the required oxygen levels

  19. Microgravity

    NASA Image and Video Library

    1998-01-01

    The heart of the bioreactor is the rotating wall vessel, shown without its support equipment. Volume is about 125 mL. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  20. NASA's Bioreactor: Growing Cells in a Simulated Microgravity Environment

    NASA Technical Reports Server (NTRS)

    Richardson, Denise

    2003-01-01

    National Science Education Standards (NSES), Science for All Americans, the Secretary's Commission on Achieving Necessary Skills (SCANS) as well as the National Aeronautics and Space Administration (NASA) are all making an effort to promote scientific literacy in America. Unfortunately, major evaluation programs such as the National Assessment of Educational Progress (NAEP) and the Third International Mathematics and Science Study (TIMSS) have provided information that suggested our students are not able to compete with peers from comparable countries. Although results indicated that American students are recalling memorized, factual knowledge well enough, the real problem is the ability to apply what they know. Concerned with these reports, the National Science Teacher's Association (NSTA) has developed a mission to support innovation and high quality in science teaching and learning for every student. NSTA recommends less emphasis on factual knowledge (memorization) and information and more understanding of the concepts. Science process skills are considered imperative to prepare America's students for the 21st century. The National Aeronautics and Space Administration (NASA) supports this mission and adds that NASA strives to help prepare and encourage the next generation of researchers and explorers. One method that NASA supports educators and its mission is to publish educational briefs. NASA describes a brief as a publication that ranges from one-to-thirty pages. The focus is on mission discoveries and results. The brief provides curriculum to educators that supports their objectives and NASA's interest. Educational Briefs are specific to the grade level and course so that educators may have choices that fit their methods and students level. Sometimes, the brief includes lessons and activities teachers may use. For example, NASA's Microgravity Division has designed a student bioreactor. Consequently, an Educational Brief is being written that focuses on how

  1. Microgravity

    NASA Image and Video Library

    1996-01-01

    Close-up view of the interior of a NASA Bioreactor shows the plastic plumbing and valves (cylinders at right center) to control fluid flow. The rotating wall vessel is at top center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  2. Cell Cycle Progression of Human Cells Cultured in Rotating Bioreactor

    NASA Technical Reports Server (NTRS)

    Parks, Kelsey

    2009-01-01

    Space flight has been shown to alter the astronauts immune systems. Because immune performance is complex and reflects the influence of multiple organ systems within the host, scientists sought to understand the potential impact of microgravity alone on the cellular mechanisms critical to immunity. Lymphocytes and their differentiated immature form, lymphoblasts, play an important and integral role in the body's defense system. T cells, one of the three major types of lymphocytes, play a central role in cell-mediated immunity. They can be distinguished from other lymphocyte types, such as B cells and natural killer cells by the presence of a special receptor on their cell surface called T cell receptors. Reported studies have shown that spaceflight can affect the expression of cell surface markers. Cell surface markers play an important role in the ability of cells to interact and to pass signals between different cells of the same phenotype and cells of different phenotypes. Recent evidence suggests that cell-cycle regulators are essential for T-cell function. To trigger an effective immune response, lymphocytes must proliferate. The objective of this project is to investigate the changes in growth of human cells cultured in rotating bioreactors and to measure the growth rate and the cell cycle distribution for different human cell types. Human lymphocytes and lymphoblasts will be cultured in a bioreactor to simulate aspects of microgravity. The bioreactor is a cylindrical culture vessel that incorporates the aspects of clinostatic rotation of a solid fluid body around a horizontal axis at a constant speed, and compensates gravity by rotation and places cells within the fluid body into a sustained free-fall. Cell cycle progression and cell proliferation of the lymphocytes will be measured for a number of days. In addition, RNA from the cells will be isolated for expression of genes related in cell cycle regulations.

  3. Performance assessment of a pilot-size vacuum rotation membrane bioreactor treating urban wastewater

    NASA Astrophysics Data System (ADS)

    Alnaizy, Raafat; Aidan, Ahmad; Luo, Haonan

    2011-12-01

    This study investigated the suitability and performance of a pilot-scale membrane bioreactor (MBR). Huber vacuum rotation membrane (VRM 20/36) bioreactor was installed at the Sharjah sewage treatment plant (STP) in the United Arab Emirate for 12 months. The submerged membranes were flat sheets with a pore size of 0.038 μm. The VRM bioreactor provided a final effluent of very high quality. The average reduction on parameters such as COD was from 620 to 3 mg/l, BOD from 239 to 3 mg/l, Ammonia from 37 to 2 mg/l, turbidity from 225NTU to less than 3NTU, and total suspended solids from 304 mg/l to virtually no suspended solids. The rotating mechanism of the membrane panels permitted the entire membrane surface to receive the same intensive degree of air scouring, which lead to a longer duration. The MBR process holds a promising future because of its smaller footprints in contrast to conventional systems, superior effluent quality, and high loading rate capacity.

  4. Regulating Glucose and pH, and Monitoring Oxygen in a Bioreactor

    NASA Technical Reports Server (NTRS)

    Anderson, Melody M.; Pellis, Neat R.; Jeevarajan, Antony S.; Taylor, Thomas D.; Xu, Yuanhang; Gao, Frank

    2006-01-01

    A system that automatically regulates the concentration of glucose or pH in a liquid culture medium that is circulated through a rotating-wall perfused bioreactor is described. Another system monitors the concentration of oxygen in the culture medium.

  5. Microgravity

    NASA Image and Video Library

    1996-01-01

    Exterior view of the NASA Bioreactor Engineering Development Unit flown on Mir. The rotating wall vessel is behind the window on the face of the large module. Control electronics are in the module at left; gas supply and cooling fans are in the module at back. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  6. Video of Tissue Grown in Space in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Principal investigator Leland Chung grew prostate cancer and bone stromal cells aboard the Space Shuttle Columbia during the STS-107 mission. Although the experiment samples were lost along with the ill-fated spacecraft and crew, he did obtain downlinked video of the experiment that indicates the enormous potential of growing tissues in microgravity. Cells grown aboard Columbia had grown far larger tissue aggregates at day 5 than did the cells grown in a NASA bioreactor on the ground.

  7. Bioreactor Yields Extracts for Skin Cream

    NASA Technical Reports Server (NTRS)

    2015-01-01

    Johnson Space Flight Center researchers created a unique rotating-wall bioreactor that simulates microgravity conditions, spurring innovations in drug development and medical research. Renuèll Int'l Inc., based in Aventure, Florida, licensed the technology and used it to produce a healing skin care product, RE`JUVEL. In a Food and Drug Administration test, RE`JUVEL substantially increased skin moisture and elasticity while reducing dark blotches and wrinkles.

  8. Design of a flow perfusion bioreactor system for bone tissue-engineering applications.

    PubMed

    Bancroft, Gregory N; Sikavitsas, Vassilios I; Mikos, Antonios G

    2003-06-01

    Several different bioreactors have been investigated for tissue-engineering applications. Among these bioreactors are the spinner flask and the rotating wall vessel reactor. In addition, a new type of culture system has been developed and investigated, the flow perfusion culture bioreactor. Flow perfusion culture offers several advantages, notably the ability to mitigate both external and internal diffusional limitations as well as to apply mechanical stress to the cultured cells. For such investigation, a flow perfusion culture system was designed and built. This design is the outgrowth of important design requirements and incorporates features crucial to successful experimentation with such a system.

  9. An update to space biomedical research: tissue engineering in microgravity bioreactors.

    PubMed

    Barzegari, Abolfazl; Saei, Amir Ata

    2012-01-01

    The severe need for constructing replacement tissues in organ transplanta-tion has necessitated the development of tissue engineering approaches and bioreactors that can bring these approaches to reality. The inherent limitations of conventional bioreactors in generating realistic tissue constructs led to the devise of the microgravity tissue engineering that uses Rotating Wall Vessel (RWV) bioreactors initially developed by NASA. In this review article, we intend to highlight some major advances and accomplishments in the rapidly-growing field of tissue engineering that could not be achieved without using microgravity. Research is now focused on assembly of 3 dimensional (3D) tissue fragments from various cell types in human body such as chon-drocytes, osteoblasts, embryonic and mesenchymal stem cells, hepatocytes and pancreas islet cells. Hepatocytes cultured under microgravity are now being used in extracorporeal bioartificial liver devices. Tissue constructs can be used not only in organ replacement therapy, but also in pharmaco-toxicology and food safety assessment. 3D models of vari-ous cancers may be used in studying cancer development and biology or in high-throughput screening of anticancer drug candidates. Finally, 3D heterogeneous assemblies from cancer/immune cells provide models for immunotherapy of cancer. Tissue engineering in (simulated) microgravity has been one of the stunning impacts of space research on biomedical sciences and their applications on earth.

  10. Microgravity

    NASA Image and Video Library

    1996-01-01

    Close-up view of the interior of a NASA Bioreactor shows the plastic plumbing and valves (cylinders at center) to control fluid flow. A fresh nutrient bag is installed at top; a flattened waste bag behind it will fill as the nutrients are consumed during the course of operation. The drive chain and gears for the rotating wall vessel are visible at bottom center center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  11. Biotechnology

    NASA Image and Video Library

    2003-01-22

    Salmonella typhimurium appears green in on human intestinal tissue (stained red) cultured in a NASA rotating wall bioreactor. Dr. Cheryl Nickerson of Tulane University is studying the effects of simulated low-g on a well-known pathogen, Salmonella typhimurium, a bacterium that causes two to four million cases of gastrointestinal illness in the United States each year. While most healthy people recover readily, S. typhimurium can kill people with weakened immune systems. Thus, a simple case of food poisoning could disrupt a space mission. Using the NASA rotating-wall bioreactor, Nickerson cultured S. typhimurium in modeled microgravity. Mice infected with the bacterium died an average of three days faster than the control mice, indicating that S. typhimurium's virulence was enhanced by the bioreactor. Earlier research showed that 3 percent of the genes were altered by exposure to the bioreactor. Nickerson's work earned her a 2001 Presidential Early Career Award for Scientists and Engineers.

  12. A comparison of bioreactors for culture of fetal mesenchymal stem cells for bone tissue engineering.

    PubMed

    Zhang, Zhi-Yong; Teoh, Swee Hin; Teo, Erin Yiling; Khoon Chong, Mark Seow; Shin, Chong Woon; Tien, Foo Toon; Choolani, Mahesh A; Chan, Jerry K Y

    2010-11-01

    Bioreactors provide a dynamic culture system for efficient exchange of nutrients and mechanical stimulus necessary for the generation of effective tissue engineered bone grafts (TEBG). We have shown that biaxial rotating (BXR) bioreactor-matured human fetal mesenchymal stem cell (hfMSC) mediated-TEBG can heal a rat critical sized femoral defect. However, it is not known whether optimal bioreactors exist for bone TE (BTE) applications. We systematically compared this BXR bioreactor with three most commonly used systems: Spinner Flask (SF), Perfusion and Rotating Wall Vessel (RWV) bioreactors, for their application in BTE. The BXR bioreactor achieved higher levels of cellularity and confluence (1.4-2.5x, p < 0.05) in large 785 mm(3) macroporous scaffolds not achieved in the other bioreactors operating in optimal settings. BXR bioreactor-treated scaffolds experienced earlier and more robust osteogenic differentiation on von Kossa staining, ALP induction (1.2-1.6×, p < 0.01) and calcium deposition (1.3-2.3×, p < 0.01). We developed a Micro CT quantification method which demonstrated homogenous distribution of hfMSC in BXR bioreactor-treated grafts, but not with the other three. BXR bioreactor enabled superior cellular proliferation, spatial distribution and osteogenic induction of hfMSC over other commonly used bioreactors. In addition, we developed and validated a non-invasive quantitative micro CT-based technique for analyzing neo-tissue formation and its spatial distribution within scaffolds. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Mathematical modeling of the flow field and particle motion in a rotating bioreactor at unit gravity and microgravity

    NASA Technical Reports Server (NTRS)

    Boyd, Ernest J.

    1990-01-01

    The biotechnology group at NASA Johnson Space Center is developing systems for culturing mammalian cells that stimulate some aspect of microgravity and provide a low shear environment for microgravity-based studies on suspension and anchorage dependent cells. The design of these vessels for culturing cells is based on the need to suspend cells and aggregates of cells and microcarrier beads continually in the culturing medium. The design must also provide sufficient circulation for adequate mass transfer of nutrients to the cells and minimize the total force on the cells. Forces, resulting from sources such as hydrodynamic fluid shear and collisions of cells and walls of the vessels, may damage delicate cells and degrade the formation of three dimensional structures. This study examines one particular design in both unit gravity and microgravity based on two concentric cylinders rotating in the same direction at different speeds to create a Couette flow between them. A numerical simulation for the flow field and the trajectories of particles in the vessel. The flow field for the circulation of the culturing medium is modeled by the Navier-Stokes equations. The forces on a particle are assumed to be drag from the fluid's circulation, buoyancy from the gravitational force and centrifugal force from the rotation of the vessel. The problem requires first solving the system of partial differential equations for the fluid flow by a finite difference method and then solving the system of ordinary differential equations for the trajectories by Gear's stiff method. Results of the study indicate that the trajectories in unit gravity and microgravity are very similar except for small spatial deviations on the fast time scale in unit gravity. The total force per unit cross sectional area on a particle in microgravity, however, is significantly smaller than the corresponding value in unit gravity, which is also smaller than anticipated. Hence, this study indicates that this

  14. NASA-approved rotary bioreactor enhances proliferation of human epidermal stem cells and supports formation of 3D epidermis-like structure.

    PubMed

    Lei, Xiao-hua; Ning, Li-na; Cao, Yu-jing; Liu, Shuang; Zhang, Shou-bing; Qiu, Zhi-fang; Hu, Hui-min; Zhang, Hui-shan; Liu, Shu; Duan, En-kui

    2011-01-01

    The skin is susceptible to different injuries and diseases. One major obstacle in skin tissue engineering is how to develop functional three-dimensional (3D) substitute for damaged skin. Previous studies have proved a 3D dynamic simulated microgravity (SMG) culture system as a "stimulatory" environment for the proliferation and differentiation of stem cells. Here, we employed the NASA-approved rotary bioreactor to investigate the proliferation and differentiation of human epidermal stem cells (hEpSCs). hEpSCs were isolated from children foreskins and enriched by collecting epidermal stem cell colonies. Cytodex-3 micro-carriers and hEpSCs were co-cultured in the rotary bioreactor and 6-well dish for 15 days. The result showed that hEpSCs cultured in rotary bioreactor exhibited enhanced proliferation and viability surpassing those cultured in static conditions. Additionally, immunostaining analysis confirmed higher percentage of ki67 positive cells in rotary bioreactor compared with the static culture. In contrast, comparing with static culture, cells in the rotary bioreactor displayed a low expression of involucrin at day 10. Histological analysis revealed that cells cultured in rotary bioreactor aggregated on the micro-carriers and formed multilayer 3D epidermis structures. In conclusion, our research suggests that NASA-approved rotary bioreactor can support the proliferation of hEpSCs and provide a strategy to form multilayer epidermis structure.

  15. Microgravity

    NASA Image and Video Library

    1998-10-10

    Time-lapse exposure depicts Bioreactor rotation. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues.

  16. A study of the Coriolis effect on the fluid flow profile in a centrifugal bioreactor.

    PubMed

    Detzel, Christopher J; Thorson, Michael R; Van Wie, Bernard J; Ivory, Cornelius F

    2009-01-01

    Increasing demand for tissues, proteins, and antibodies derived from cell culture is necessitating the development and implementation of high cell density bioreactors. A system for studying high density culture is the centrifugal bioreactor (CCBR), which retains cells by increasing settling velocities through system rotation, thereby eliminating diffusional limitations associated with mechanical cell retention devices. This article focuses on the fluid mechanics of the CCBR system by considering Coriolis effects. Such considerations for centrifugal bioprocessing have heretofore been ignored; therefore, a simpler analysis of an empty chamber will be performed. Comparisons are made between numerical simulations and bromophenol blue dye injection experiments. For the non-rotating bioreactor with an inlet velocity of 4.3 cm/s, both the numerical and experimental results show the formation of a teardrop shaped plume of dye following streamlines through the reactor. However, as the reactor is rotated, the simulation predicts the development of vortices and a flow profile dominated by Coriolis forces resulting in the majority of flow up the leading wall of the reactor as dye initially enters the chamber, results are confirmed by experimental observations. As the reactor continues to fill with dye, the simulation predicts dye movement up both walls while experimental observations show the reactor fills with dye from the exit to the inlet. Differences between the simulation and experimental observations can be explained by excessive diffusion required for simulation convergence, and a slight density difference between dyed and un-dyed solutions. Implications of the results on practical bioreactor use are also discussed. (c) 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009.

  17. A Study of the Coriolis Effect on the Fluid Flow Profile in a Centrifugal Bioreactor

    PubMed Central

    Detzel, Christopher J.; Thorson, Michael R.; Van Wie, Bernard J.; Ivory, Cornelius F.

    2011-01-01

    Increasing demand for tissues, proteins, and antibodies derived from cell culture is necessitating the development and implementation of high cell density bioreactors. A system for studying high density culture is the centrifugal bioreactor (CCBR) which retains cells by increasing settling velocities through system rotation, thereby eliminating diffusional limitations associated with mechanical cell retention devices. This paper focuses on the fluid mechanics of the CCBR system by considering Coriolis effects. Such considerations for centrifugal bioprocessing have heretofore been ignored; therefore a simpler analysis of an empty chamber will be performed. Comparisons are made between numerical simulations and bromophenol blue dye injection experiments. For the non-rotating bioreactor with an inlet velocity of 4.3 cm/s, both the numerical and experimental results show the formation of a teardrop shaped plume of dye following streamlines through the reactor. However, as the reactor is rotated the simulation predicts the development of vortices and a flow profile dominated by Coriolis forces resulting in the majority of flow up the leading wall of the reactor as dye initially enters the chamber, results confirmed by experimental observations. As the reactor continues to fill with dye, the simulation predicts dye movement up both walls while experimental observations show the reactor fills with dye from the exit to the inlet. Differences between the simulation and experimental observations can be explained by excessive diffusion required for simulation convergence, and a slight density difference between dyed and un-dyed solutions. Implications of the results on practical bioreactor use are also discussed. PMID:19455639

  18. Numerical simulation of fluid flow in a rotational bioreactor

    NASA Astrophysics Data System (ADS)

    Ganimedov, V. L.; Papaeva, E. O.; Maslov, N. A.; Larionov, P. M.

    2017-10-01

    Application of scaffold technology for the problem of bone tissue regeneration has great prospects in modern medicine. The influence of fluid shear stress on stem cells cultivation and its differentiation into osteoblasts is the subject of intensive research. Mathematical modeling of fluid flow in bioreactor allowed us to determine the structure of flow and estimate the level of mechanical stress on cells. The series of computations for different rotation frequencies (0.083, 0.124, 0.167, 0.2 and 0.233 Hz) was performed for the laminar flow regime approximation. It was shown that the Taylor vortices in the gap between the cylinders qualitatively change the distribution of static pressure and shear stress in the region of vortices connection. It was shown that an increase in the rotation frequency leads to an increase of the unevenness in distribution of the above mentioned functions. The obtained shear stress and static pressure dependence on the rotational frequency make it possible to choose the operating mode of the reactor depending on the provided requirements. It was shown that in the range of rotation frequencies chosen in this work (0.083 < f < 0.233 Hz), the shear stress does not exceed the known literature data (0.002 - 0.1 Pa).

  19. Reconstitution of hepatic tissue architectures from fetal liver cells obtained from a three-dimensional culture with a rotating wall vessel bioreactor.

    PubMed

    Ishikawa, Momotaro; Sekine, Keisuke; Okamura, Ai; Zheng, Yun-wen; Ueno, Yasuharu; Koike, Naoto; Tanaka, Junzo; Taniguchi, Hideki

    2011-06-01

    Reconstitution of tissue architecture in vitro is important because it enables researchers to investigate the interactions and mutual relationships between cells and cellular signals involved in the three-dimensional (3D) construction of tissues. To date, in vitro methods for producing tissues with highly ordered structure and high levels of function have met with limited success although a variety of 3D culture systems have been investigated. In this study, we reconstituted functional hepatic tissue including mature hepatocyte and blood vessel-like structures accompanied with bile duct-like structures from E15.5 fetal liver cells, which contained more hepatic stem/progenitor cells comparing with neonatal liver cells. The culture was performed in a simulated microgravity environment produced by a rotating wall vessel (RWV) bioreactor. The hepatocytes in the reconstituted 3D tissue were found to be capable of producing albumin and storing glycogen. Additionally, bile canaliculi between hepatocytes, characteristics of adult hepatocyte in vivo were also formed. Apart from this, bile duct structure secreting mucin was shown to form complicated tubular branches. Furthermore, gene expression analysis by semi-quantitative RT-PCR revealed the elevated levels of mature hepatocyte markers as well as genes with the hepatic function. With RWV culture system, we could produce functionally reconstituted liver tissue and this might be useful in pharmaceutical industry including drug screening and testing and other applications such as an alternative approach to experimental animals. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  20. Morphological Differentiation of Colon Carcinoma Cell Lines in Rotating Wall Vessels

    NASA Technical Reports Server (NTRS)

    Jessup, J. M.

    1994-01-01

    The objectives of this project were to determine whether (1) microgravity permits unique, three-dimensional cultures of neoplastic human colon tissues and (2) this culture interaction produces novel intestinal growth and differentiation factors. The initial phase of this project tested the efficacy of simulated microgravity for the cultivation and differentiation of human colon carcinoma in rotating wall vessels (RWV's) on microcarrier beads. The RWV's simulate microgravity by randomizing the gravity vector in an aqueous medium under a low shear stress environment in unit gravity. This simulation achieves approximately a one-fifth g environment that allows cells to 'float' and form three-dimensional relationships with less shear stress than in other stirred aqueous medium bioreactors. In the second phase of this project we assessed the ability of human colon carcinoma lines to adhere to various substrates because adhesion is the first event that must occur to create three-dimensional masses. Finally, we tested growth factor production in the last phase of this project.

  1. STS-44 DS0 316, Bioreactor/Flow and Particle Trajectory in Microgravity, hdwr

    NASA Technical Reports Server (NTRS)

    1991-01-01

    STS-44 Detailed Supplementary Objective (DSO) 316, Bioreactor/Flow and Particle Trajectory in Microgravity, rotating wall vessels are stored in an incubator in JSC's Life Sciences Laboratory Bldg 37 Biotechnology Laboratories. The rotating wall vessel hardware will receive its first test and equipment checkout on the middeck of Atlantis, Orbiter Vehicle (OV) 104, during the STS-44 mission. The vessel hardware will be used in a test that researchers hope will confirm their theories and calculations about how the flow fields work in space. Plastic beads of various sizes rather than cell cultures are being flown in the vessel for the STS-44 test.

  2. Continuous pH monitoring in a perfused bioreactor system using an optical pH sensor

    NASA Technical Reports Server (NTRS)

    Jeevarajan, Antony S.; Vani, Sundeep; Taylor, Thomas D.; Anderson, Melody M.

    2002-01-01

    Monitoring and regulating the pH of the solution in a bioprocess is one of the key steps in the success of bioreactor operation. An in-line optical pH sensor, based on the optical absorption properties of phenol red present in the medium, was developed and tested in this work for use in NASA space bioreactors based on a rotating wall-perfused vessel system supporting a baby hamster kidney (BHK-21) cell culture. The sensor was tested over three 30-day and one 124-day cell runs. The pH sensor initially was calibrated and then used during the entire cell culture interval. The pH reported by the sensor was compared to that measured by a fiber optically coupled Shimadzu spectrophotometer and a blood gas analyzer. The maximum standard error of prediction for all the four cell runs for development pH sensor against BGA was +/-0.06 pH unit and for the fiber optically coupled Shimadzu spectrophotometer against the blood gas analyzer was +/-0.05 pH unit. The pH sensor system performed well without need of recalibration for 124 days. Copyright 2002 Wiley Periodicals, Inc.

  3. Driving chiral domain walls in antiferromagnets using rotating magnetic fields

    NASA Astrophysics Data System (ADS)

    Pan, Keming; Xing, Lingdi; Yuan, H. Y.; Wang, Weiwei

    2018-05-01

    We show theoretically and numerically that an antiferromagnetic domain wall can be moved by a rotating magnetic field in the presence of Dzyaloshinskii-Moriya interaction (DMI). Two motion modes are found: rigid domain wall motion at low frequency (corresponding to the perfect frequency synchronization) and the oscillating motion at high frequency. In the full synchronized region, the steady velocity of the domain wall is universal, in the sense that it depends only on the frequency of the rotating field and the ratio between DMI strength and exchange constant. The domain wall velocity is independent of the Gilbert damping and the rotating field strength. Moreover, a rotating field in megahertz is sufficient to move the antiferromagnetic domain wall.

  4. Rotational stabilization of the resistive wall modes in tokamaks with a ferritic wall

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pustovitov, V. D.; National Research Nuclear University “MEPhI,” Kashirskoe sh. 31, Moscow 115409; Yanovskiy, V. V.

    The dynamics of the rotating resistive wall modes (RWMs) is analyzed in the presence of a uniform ferromagnetic resistive wall with μ{sup ^}≡μ/μ{sub 0}≤4 (μ is the wall magnetic permeability, and μ{sub 0} is the vacuum one). This mimics a possible arrangement in ITER with ferromagnetic steel in test blanket modules or in future experiments in JT-60SA tokamak [Y. Kamada, P. Barabaschi, S. Ishida, the JT-60SA Team, and JT-60SA Research Plan Contributors, Nucl. Fusion 53, 104010 (2013)]. The earlier studies predict that such a wall must provide a destabilizing influence on the plasma by reducing the beta limit and increasingmore » the growth rates, compared to the reference case with μ{sup ^}=1. This is true for the locked modes, but the presented results show that the mode rotation changes the tendency to the opposite. At μ{sup ^}>1, the rotational stabilization related to the energy sink in the wall becomes even stronger than at μ{sup ^}=1, and this “external” effect develops at lower rotation frequency, estimated as several kHz at realistic conditions. The study is based on the cylindrical dispersion relation valid for arbitrary growth rates and frequencies. This relation is solved numerically, and the solutions are compared with analytical dependences obtained for slow (s/d{sub w}≫1) and fast (s/d{sub w}≪1) “ferromagnetic” rotating RWMs, where s is the skin depth and d{sub w} is the wall thickness. It is found that the standard thin-wall modeling becomes progressively less reliable at larger μ{sup ^}, and the wall should be treated as magnetically thick. The analysis is performed assuming only a linear plasma response to external perturbations without constraints on the plasma current and pressure profiles.« less

  5. Breast Cancer Research at NASA

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Isolation of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue; A: Duct element recovered from breast tissue digest. B: Outgrowth of cells from duct element in upper right corner cultured in a standard dish; most cells spontaneousely die during early cell divisions, but a few will establish long-term growth. C: Isolate of long-term frowth HMEC from outgrowth of duct element; cells shown soon after isolation and in early full-cell contact growth in culture in a dish. D: same long-term growth HMEC, but after 3 weeks in late full-cell contact growth in a continuous culture in a dish. Note attempts to reform duct elements but this in two demensions in a dish rather than in three dimensions in tissue. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Richmond, NASA/Marshall Space Flight Center (MSFC).

  6. Clinostats and bioreactors.

    PubMed

    Klaus, D M

    2001-06-01

    The environment created on Earth within a clinostat or Rotating Wall Vessel (RWV) bioreactor is often referred to as "simulated microgravity". Both devices utilize constant reorientation to effectively nullify cumulative sedimentation of particles. Neither, however, can fully reproduce the concurrent lack of structural deformation, displacement of intercellular components and/or reduced mass transfer in the extracellular fluid that occur in actual weightlessness. Parameters including density, viscosity, and even container geometry must each be considered to determine the overall gravity-dependent effects produced by either a clinostat or the RWV bioreactor; in addition, the intended application of these two devices differs considerably. A state of particle "motionlessness" relative to the surrounding bulk fluid, which is nearly analogous to the extracellular environment encountered under weightless conditions, can theoretically be achieved through clinorotation. The RWV bioreactor, on the other hand, while similarly maintaining cells in suspension as they continually "fall" through the medium under 1 g conditions, can also purposefully induce a perfusion of nutrients to and waste from the culture. A clinostat, therefore, is typically used in an attempt to reproduce the quiescent, unstirred fluid conditions achievable on orbit; while the RWV bioreactor ideally creates a low shear, but necessarily mixed, fluid environment that is optimized for suspension culture and tissue growth. Other techniques for exploring altered inertial environments, such as freefall, neutral buoyancy and electromagnetic levitation, can also provide unique insight into how gravity affects biological systems. Ultimately, all underlying biophysical principles thought to give rise to gravity-dependent physiological responses must be identified and thoroughly examined in order to accurately interpret data from flight experiments or ground-based microgravity analogs.

  7. Fuzzy logic control of rotating drum bioreactor for improved production of amylase and protease enzymes by Aspergillus oryzae in solid-state fermentation.

    PubMed

    Sukumprasertsri, Monton; Unrean, Pornkamol; Pimsamarn, Jindarat; Kitsubun, Panit; Tongta, Anan

    2013-03-01

    In this study, we compared the performance of two control systems, fuzzy logic control (FLC) and conventional control (CC). The control systems were applied for controlling temperature and substrate moisture content in a solidstate fermentation for the biosynthesis of amylase and protease enzymes by Aspergillus oryzae. The fermentation process was achieved in a 200 L rotating drum bioreactor. Three factors affecting temperature and moisture content in the solid-state fermentation were considered. They were inlet air velocity, speed of the rotating drum bioreactor, and spray water addition. The fuzzy logic control system was designed using four input variables: air velocity, substrate temperature, fermentation time, and rotation speed. The temperature was controlled by two variables, inlet air velocity and rotational speed of bioreactor, while the moisture content was controlled by spray water. Experimental results confirmed that the FLC system could effectively control the temperature and moisture content of substrate better than the CC system, resulting in an increased enzyme production by A. oryzae. Thus, the fuzzy logic control is a promising control system that can be applied for enhanced production of enzymes in solidstate fermentation.

  8. Mathematical model of a rotational bioreactor for the dynamic cultivation of scaffold-adhered human mesenchymal stem cells for bone regeneration

    NASA Astrophysics Data System (ADS)

    Ganimedov, V. L.; Papaeva, E. O.; Maslov, N. A.; Larionov, P. M.

    2017-09-01

    Development of cell-mediated scaffold technologies for the treatment of critical bone defects is very important for the purpose of reparative bone regeneration. Today the properties of the bioreactor for cell-seeded scaffold cultivation are the subject of intensive research. We used the mathematical modeling of rotational reactor and construct computational algorithm with the help of ANSYS software package to develop this new procedure. The solution obtained with the help of the constructed computational algorithm is in good agreement with the analytical solution of Couette for the task of two coaxial cylinders. The series of flow computations for different rotation frequencies (1, 0.75, 0.5, 0.33, 1.125 Hz) was performed for the laminar flow regime approximation with the help of computational algorithm. It was found that Taylor vortices appear in the annular gap between the cylinders in a simulated bioreactor. It was obtained that shear stress in the range of interest (0.002-0.1 Pa) arise on outer surface of inner cylinder when it rotates with the frequency not exceeding 0.8 Hz. So the constructed mathematical model and the created computational algorithm for calculating the flow parameters allow predicting the shear stress and pressure values depending on the rotation frequency and geometric parameters, as well as optimizing the operating mode of the bioreactor.

  9. Bioreactors Drive Advances in Tissue Engineering

    NASA Technical Reports Server (NTRS)

    2012-01-01

    It was an unlikely moment for inspiration. Engineers David Wolf and Ray Schwarz stopped by their lab around midday. Wolf, of Johnson Space Center, and Schwarz, with NASA contractor Krug Life Sciences (now Wyle Laboratories Inc.), were part of a team tasked with developing a unique technology with the potential to enhance medical research. But that wasn t the focus at the moment: The pair was rounding up colleagues interested in grabbing some lunch. One of the lab s other Krug engineers, Tinh Trinh, was doing something that made Wolf forget about food. Trinh was toying with an electric drill. He had stuck the barrel of a syringe on the bit; it spun with a high-pitched whirr when he squeezed the drill s trigger. At the time, a multidisciplinary team of engineers and biologists including Wolf, Schwarz, Trinh, and project manager Charles D. Anderson, who formerly led the recovery of the Apollo capsules after splashdown and now worked for Krug was pursuing the development of a technology called a bioreactor, a cylindrical device used to culture human cells. The team s immediate goal was to grow human kidney cells to produce erythropoietin, a hormone that regulates red blood cell production and can be used to treat anemia. But there was a major barrier to the technology s success: Moving the liquid growth media to keep it from stagnating resulted in turbulent conditions that damaged the delicate cells, causing them to quickly die. The team was looking forward to testing the bioreactor in space, hoping the device would perform more effectively in microgravity. But on January 28, 1986, the Space Shuttle Challenger broke apart shortly after launch, killing its seven crewmembers. The subsequent grounding of the shuttle fleet had left researchers with no access to space, and thus no way to study the effects of microgravity on human cells. As Wolf looked from Trinh s syringe-capped drill to where the bioreactor sat on a workbench, he suddenly saw a possible solution to both

  10. Differentiation of cartilaginous anlage in entire embryonic mouse limbs cultured in a rotating bioreactor.

    NASA Astrophysics Data System (ADS)

    Duke, P.; Oakley, C.; Montufar-Solis, D.

    The embryonic mammalian limb is sensitive both in vivo and in vitro to changes in gravitational force. Hypergravity of centrifugation and microgravity of space decreased size of elements due to precocious or delayed chondrogenesis respectively. In recapitulating spaceflight experiments, premetatarsals were cultured in suspension in a low stress, low sheer rotating bioreactor, and found to be shorter than those cultured in standard culture dishes, and cartilage development was delayed. This study only measured length of the metatarsals, and did not account for possible changes in width and/or in form of the skeletal elements. Shorter cartilage elements in limbbuds cultured in the bioreactor may be due to the ability of the system to reproduce a more in vivo 3D shape than traditional organ cultures. Tissues subjected to traditional organ cultures become flattened by their own weight, attachment to the filter, and restrictions imposed by nutrient diffusion. The purpose of the current experiment was to determine if entire limb buds could be successfully cultured in the bioreactor, and to compare the effects on 3D shape with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were placed either in the bioreactor, in Trowell culture, or fixed as controls. Limbbuds were cultured for six days, fixed, and processed either as whole mounts or embedded for histology. Qualitative analysis revealed that the Trowell culture specimens were flattened, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections of limbbuds from both types of cultures had excellent cartilage differentiation, with apparently more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Morphometric quantitation of the cartilaginous elements for comparisons of the two culture systems was complicated due to some limb buds fusing together during culture. This problem was especially noticeable in the younger limbs, and

  11. Rotating three-dimensional dynamic culture of adult human bone marrow-derived cells for tissue engineering of hyaline cartilage.

    PubMed

    Sakai, Shinsuke; Mishima, Hajime; Ishii, Tomoo; Akaogi, Hiroshi; Yoshioka, Tomokazu; Ohyabu, Yoshimi; Chang, Fei; Ochiai, Naoyuki; Uemura, Toshimasa

    2009-04-01

    The method of constructing cartilage tissue from bone marrow-derived cells in vitro is considered a valuable technique for hyaline cartilage regenerative medicine. Using a rotating wall vessel (RWV) bioreactor developed in a NASA space experiment, we attempted to efficiently construct hyaline cartilage tissue from human bone marrow-derived cells without using a scaffold. Bone marrow aspirates were obtained from the iliac crest of nine patients during orthopedic operation. After their proliferation in monolayer culture, the adherent cells were cultured in the RWV bioreactor with chondrogenic medium for 2 weeks. Cells from the same source were cultured in pellet culture as controls. Histological and immunohistological evaluations (collagen type I and II) and quantification of glycosaminoglycan were performed on formed tissues and compared. The engineered constructs obtained using the RWV bioreactor showed strong features of hyaline cartilage in terms of their morphology as determined by histological and immunohistological evaluations. The glycosaminoglycan contents per microg DNA of the tissues were 10.01 +/- 3.49 microg/microg DNA in the case of the RWV bioreactor and 6.27 +/- 3.41 microg/microg DNA in the case of the pellet culture, and their difference was significant. The RWV bioreactor could provide an excellent environment for three-dimensional cartilage tissue architecture that can promote the chondrogenic differentiation of adult human bone marrow-derived cells.

  12. Improved function and growth of pancreatic cells in a three-dimensional bioreactor environment.

    PubMed

    Samuelson, Lisa; Gerber, David A

    2013-01-01

    Methods of three-dimensional (3D) cell culture have made significant progress in recent years due to a better understanding of cell to cell interactions and the cell's interface with their surrounding environment. We hypothesized that a microgravity 3D culture system would improve upon the growth and function of a pancreatic progenitor cell population. We developed a rotating wall vessel bioreactor and established a culture system using a pancreatic cell line. Cells in the bioreactors showed robust proliferation, enhanced transcriptional signaling, and improved translation of pancreatic genes compared with two-dimensional static culture. Cells also gained the ability to respond to glucose stimulation, which was not observed in the control cultures. These findings suggest that a 3D microgravity bioreactor environment mimics the niche of the pancreas yielding a cell source with potential for cell-based therapy in the treatment of diabetes.

  13. Particle Trajectories in Rotating Wall Cell Culture Devices

    NASA Technical Reports Server (NTRS)

    Ramachandran N.; Downey, J. P.

    1999-01-01

    Cell cultures are extremely important to the medical community since such cultures provide an opportunity to perform research on human tissue without the concerns inherent in experiments on individual humans. Development of cells in cultures has been found to be greatly influenced by the conditions of the culture. Much work has focused on the effect of the motions of cells in the culture relative to the solution. Recently rotating wall vessels have been used with success in achieving improved cellular cultures. Speculation and limited research have focused on the low shear environment and the ability of rotating vessels to keep cells suspended in solution rather than floating or sedimenting as the primary reasons for the improved cellular cultures using these devices. It is widely believed that the cultures obtained using a rotating wall vessel simulates to some degree the effect of microgravity on cultures. It has also been speculated that the microgravity environment may provide the ideal acceleration environment for culturing of cellular tissues due to the nearly negligible levels of sedimentation and shear possible. This work predicts particle trajectories of cells in rotating wall vessels of cylindrical and annular design consistent with the estimated properties of typical cellular cultures. Estimates of the shear encountered by cells in solution and the interactions with walls are studied. Comparisons of potential experiments in ground and microgravity environments are performed.

  14. Microgravity

    NASA Image and Video Library

    1998-10-10

    Human primary breast tumor cells after 49 days of growth in a NASA Bioreactor. Tumor cells aggregate on microcarrier beads (indicated by arrow). NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Jearne Becker, University of South Florida

  15. Numerical simulation of fluid field and in vitro three-dimensional fabrication of tissue-engineered bones in a rotating bioreactor and in vivo implantation for repairing segmental bone defects.

    PubMed

    Song, Kedong; Wang, Hai; Zhang, Bowen; Lim, Mayasari; Liu, Yingchao; Liu, Tianqing

    2013-03-01

    In this paper, two-dimensional flow field simulation was conducted to determine shear stresses and velocity profiles for bone tissue engineering in a rotating wall vessel bioreactor (RWVB). In addition, in vitro three-dimensional fabrication of tissue-engineered bones was carried out in optimized bioreactor conditions, and in vivo implantation using fabricated bones was performed for segmental bone defects of Zelanian rabbits. The distribution of dynamic pressure, total pressure, shear stress, and velocity within the culture chamber was calculated for different scaffold locations. According to the simulation results, the dynamic pressure, velocity, and shear stress around the surface of cell-scaffold construction periodically changed at different locations of the RWVB, which could result in periodical stress stimulation for fabricated tissue constructs. However, overall shear stresses were relatively low, and the fluid velocities were uniform in the bioreactor. Our in vitro experiments showed that the number of cells cultured in the RWVB was five times higher than those cultured in a T-flask. The tissue-engineered bones grew very well in the RWVB. This study demonstrates that stress stimulation in an RWVB can be beneficial for cell/bio-derived bone constructs fabricated in an RWVB, with an application for repairing segmental bone defects.

  16. Optimized suspension culture: the rotating-wall vessel

    NASA Technical Reports Server (NTRS)

    Hammond, T. G.; Hammond, J. M.

    2001-01-01

    Suspension culture remains a popular modality, which manipulates mechanical culture conditions to maintain the specialized features of cultured cells. The rotating-wall vessel is a suspension culture vessel optimized to produce laminar flow and minimize the mechanical stresses on cell aggregates in culture. This review summarizes the engineering principles, which allow optimal suspension culture conditions to be established, and the boundary conditions, which limit this process. We suggest that to minimize mechanical damage and optimize differentiation of cultured cells, suspension culture should be performed in a solid-body rotation Couette-flow, zero-headspace culture vessel such as the rotating-wall vessel. This provides fluid dynamic operating principles characterized by 1) solid body rotation about a horizontal axis, characterized by colocalization of cells and aggregates of different sedimentation rates, optimally reduced fluid shear and turbulence, and three-dimensional spatial freedom; and 2) oxygenation by diffusion. Optimization of suspension culture is achieved by applying three tradeoffs. First, terminal velocity should be minimized by choosing microcarrier beads and culture media as close in density as possible. Next, rotation in the rotating-wall vessel induces both Coriolis and centrifugal forces, directly dependent on terminal velocity and minimized as terminal velocity is minimized. Last, mass transport of nutrients to a cell in suspension culture depends on both terminal velocity and diffusion of nutrients. In the transduction of mechanical culture conditions into cellular effects, several lines of evidence support a role for multiple molecular mechanisms. These include effects of shear stress, changes in cell cycle and cell death pathways, and upstream regulation of secondary messengers such as protein kinase C. The discipline of suspension culture needs a systematic analysis of the relationship between mechanical culture conditions and

  17. Three-Dimensional Transgenic Cell Models to Quantify Space Genotoxic Effects

    NASA Technical Reports Server (NTRS)

    Gonda, S.; Wu, H.; Pingerelli, P.; Glickman, B.

    2000-01-01

    In this paper we describe a three-dimensional, multicellular tissue-equivalent model, produced in NASA-designed, rotating wall bioreactors using mammalian cells engineered for genomic containment of mUltiple copies of defined target genes for genotoxic assessment. The Rat 2(lambda) fibroblasts (Stratagene, Inc.) were genetically engineered to contain high-density target genes for mutagenesis. Stable three-dimensional, multicellular spheroids were formed when human mammary epithelial cells and Rat 2(lambda) fibroblasts were cocultured on Cytodex 3 Beads in a rotating wall bioreactor. The utility of this spheroidal model for genotoxic assessment was indicated by a linear dose response curve and by results of gene sequence analysis of mutant clones from 400micron diameter spheroids following low-dose, high-energy, neon radiation exposure

  18. Microgravity

    NASA Image and Video Library

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101823 for a version without labels, and No. 0103180 for an operational schematic.

  19. Microgravity

    NASA Image and Video Library

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101816 for a version without labels, and No. 0103180 for an operational schematic.

  20. Microgravity

    NASA Image and Video Library

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101825 for a version with major elements labeled, and No. 0103180 for an operational schematic. 0101816

  1. Microgravity

    NASA Image and Video Library

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101824 for a version with labels, and No. 0103180 for an operational schematic.

  2. Large Scale Expansion of Human Umbilical Cord Cells in a Rotating Bed System Bioreactor for Cardiovascular Tissue Engineering Applications

    PubMed Central

    Reichardt, Anne; Polchow, Bianca; Shakibaei, Mehdi; Henrich, Wolfgang; Hetzer, Roland; Lueders, Cora

    2013-01-01

    Widespread use of human umbilical cord cells for cardiovascular tissue engineering requires production of large numbers of well-characterized cells under controlled conditions. In current research projects, the expansion of cells to be used to create a tissue construct is usually performed in static cell culture systems which are, however, often not satisfactory due to limitations in nutrient and oxygen supply. To overcome these limitations dynamic cell expansion in bioreactor systems under controllable conditions could be an important tool providing continuous perfusion for the generation of large numbers of viable pre-conditioned cells in a short time period. For this purpose cells derived from human umbilical cord arteries were expanded in a rotating bed system bioreactor for up to 9 days. For a comparative study, cells were cultivated under static conditions in standard culture devices. Our results demonstrated that the microenvironment in the perfusion bioreactor was more favorable than that of the standard cell culture flasks. Data suggested that cells in the bioreactor expanded 39 fold (38.7 ± 6.1 fold) in comparison to statically cultured cells (31.8 ± 3.0 fold). Large-scale production of cells in the bioreactor resulted in more than 3 x 108 cells from a single umbilical cord fragment within 9 days. Furthermore cell doubling time was lower in the bioreactor system and production of extracellular matrix components was higher. With this study, we present an appropriate method to expand human umbilical cord artery derived cells with high cellular proliferation rates in a well-defined bioreactor system under GMP conditions. PMID:23847691

  3. Reduced-Gravity Experiments Conducted to Help Bioreactor Development

    NASA Technical Reports Server (NTRS)

    Niederhaus, Charles E.; Nahra, Henry K.; Kizito, John P.

    2004-01-01

    The NASA Glenn Research Center and the NASA Johnson Space Center are collaborating on fluid dynamic investigations for a future cell science bioreactor to fly on the International Space Station (ISS). Project Manager Steven Gonda from the Cellular Biotechnology Program at Johnson is leading the development of the Hydrodynamic Focusing Bioreactor--Space (HFB-S) for use on the ISS to study tissue growth in microgravity. Glenn is providing microgravity fluid physics expertise to help with the design and evaluation of the HFB-S. These bioreactors are used for three-dimensional tissue culture, which cannot be done in ground-based labs in normal gravity. The bioreactors provide a continual supply of oxygen for cell growth, as well as periodic replacement of cell culture media with nutrients. The bioreactor must provide a uniform distribution of oxygen and nutrients while minimizing the shear stresses on the tissue culture.

  4. Morphologic differentiation of colon carcinoma cell lines HT-29 and HT-29KM in rotating-wall vessels

    NASA Technical Reports Server (NTRS)

    Goodwin, T. J.; Jessup, J. M.; Wolf, D. A.

    1992-01-01

    A new low shear stress microcarrier culture system has been developed at NASA's Johnson Space Center that permits three-dimensional tissue culture. Two established human colon adenocarcinoma cell lines, HT-29, an undifferentiated, and HT-29KM, a stable, moderately differentiated subline of HT-29, were grown in new tissue culture bioreactors called Rotating-Wall Vessels (RWVs). RWVs are used in conjunction with multicellular cocultivation to develop a unique in vitro tissue modeling system. Cells were cultivated on Cytodex-3 microcarrier beads, with and without mixed normal human colonic fibroblasts, which served as the mesenchymal layer. Culture of the tumor lines in the absence of fibroblasts produced spheroidlike growth and minimal differentiation. In contrast, when tumor lines were co-cultivated with normal colonic fibroblasts, initial growth was confined to the fibroblast population until the microcarriers were covered. The tumor cells then commenced proliferation at an accelerated rate, organizing themselves into three-dimensional tissue masses that achieved 1.0- to 1.5-cm diameters. The masses displayed glandular structures, apical and internal glandular microvilli, tight intercellular junctions, desmosomes, cellular polarity, sinusoid development, internalized mucin, and structural organization akin to normal colon crypt development. Differentiated samples were subjected to transmission and scanning electron microscopy and histologic analysis, revealing embryoniclike mesenchymal cells lining the areas around the growth matrices. Necrosis was minimal throughout the tissue masses. These data suggest that the RWV affords a new model for investigation and isolation of growth, regulatory, and structural processes within neoplastic and normal tissue.

  5. Theoretical axial wall angulation for rotational resistance form in an experimental-fixed partial denture

    PubMed Central

    2017-01-01

    PURPOSE The aim of this study was to determine the influence of long base lengths of a fixed partial denture (FPD) to rotational resistance with variation of vertical wall angulation. MATERIALS AND METHODS Trigonometric calculations were done to determine the maximum wall angle needed to resist rotational displacement of an experimental-FPD model in 2-dimensional plane. The maximum wall angle calculation determines the greatest taper that resists rotation. Two different axes of rotation were used to test this model with five vertical abutment heights of 3-, 3.5-, 4-, 4.5-, and 5-mm. The two rotational axes were located on the mesial-side of the anterior abutment and the distal-side of the posterior abutment. Rotation of the FPD around the anterior axis was counter-clockwise, Posterior-Anterior (P-A) and clockwise, Anterior-Posterior (A-P) around the distal axis in the sagittal plane. RESULTS Low levels of vertical wall taper, ≤ 10-degrees, were needed to resist rotational displacement in all wall height categories; 2–to–6–degrees is generally considered ideal, with 7–to–10–degrees as favorable to the long axis of the abutment. Rotation around both axes demonstrated that two axial walls of the FPD resisted rotational displacement in each direction. In addition, uneven abutment height combinations required the lowest wall angulations to achieve resistance in this study. CONCLUSION The vertical height and angulation of FPD abutments, two rotational axes, and the long base lengths all play a role in FPD resistance form. PMID:28874995

  6. Scale up of diesel oil biodegradation in a baffled roller bioreactor.

    PubMed

    Nikakhtari, Hossein; Song, Wanning; Kumar, Pardeep; Nemati, Mehdi; Hill, Gordon A

    2010-05-01

    Diesel oil is a suitable substance to represent petroleum contamination from accidental spills in operating and transportation facilities. Using a microbial culture enriched from a petroleum contaminated soil, biodegradation of diesel oil was carried out in 2.2, 55, and 220 L roller baffled bioreactors. The effects of bioreactor rotation speed (from 5 to 45 rpm) and liquid loading (from 18% to 73% of total volume) on the biodegradation of diesel oil were studied. In the small scale bioreactor (2.2L), the maximum rotation speed of 45 rpm resulted in the highest biodegradation rate with a first order biodegradation kinetic constant of 0.095 d(-1). In the larger scale bioreactors, rotation speed did not affect the biodegradation rate. Liquid loadings higher than 64% resulted in reduced biodegradation rates in the small scale bioreactor; however, in the larger roller bioreactors liquid loading did not affect the biodegradation rate. Biodegradation of diesel oil at 5 rpm and 73% loading is recommended for operating large scale roller baffled bioreactors. Under these conditions, high diesel oil concentrations up to 50 gL(-1) can be bioremediated at a rate of 1.61 gL(-1)d(-1). Copyright 2010 Elsevier Ltd. All rights reserved.

  7. The Effect of Simulated Microgravity Environment of RWV Bioreactors on Surface Reactions and Adsorption of Serum Proteins on Bone-bioactive Microcarriers

    NASA Technical Reports Server (NTRS)

    Radin, Shula; Ducheyne, P.; Ayyaswamy, P. S.

    2003-01-01

    Biomimetically modified bioactive materials with bone-like surface properties are attractive candidates for use as microcarriers for 3-D bone-like tissue engineering under simulated microgravity conditions of NASA designed rotating wall vessel (RWV) bioreactors. The simulated microgravity environment is attainable under suitable parametric conditions of the RWV bioreactors. Ca-P containing bioactive glass (BG), whose stimulatory effect on bone cell function had been previously demonstrated, was used in the present study. BG surface modification via reactions in solution, resulting formation of bone-like minerals at the surface and adsorption of serum proteins is critical for obtaining the stimulatory effect. In this paper, we report on the major effects of simulated microgravity conditions of the RWV on the BG reactions surface reactions and protein adsorption in physiological solutions. Control tests at normal gravity were conducted at static and dynamic conditions. The study revealed that simulated microgravity remarkably enhanced reactions involved in the BG surface modification, including BG dissolution, formation of bone-like minerals at the surface and adsorption of serum proteins. Simultaneously, numerical models were developed to simulate the mass transport of chemical species to and from the BG surface under normal gravity and simulated microgravity conditions. The numerical results showed an excellent agreement with the experimental data at both testing conditions.

  8. Two Devices for Removing Sludge From Bioreactor Wastewater

    NASA Technical Reports Server (NTRS)

    Archer, Shivaun; Hitchens, G. DUncan; Jabs, Harry; Cross, Jennifer; Pilkinton, Michelle; Taylor, Michael

    2007-01-01

    Two devices a magnetic separator and a special filter denoted a self-regenerating separator (SRS) have been developed for separating sludge from the stream of wastewater from a bioreactor. These devices were originally intended for use in microgravity, but have also been demonstrated to function in normal Earth gravity. The magnetic separator (see Figure 1) includes a thin-walled nonmagnetic, stainless-steel cylindrical drum that rotates within a cylindrical housing. The wastewater enters the separator through a recirculation inlet, and about 80 percent of the wastewater flow leaves through a recirculation outlet. Inside the drum, a magnet holder positions strong permanent magnets stationary and, except near a recirculation outlet, close to the inner drum surface. To enable magnetic separation, magnetite (a ferromagnetic and magnetically soft iron oxide) powder is mixed into the bioreactor wastewater. The magnetite becomes incorporated into the sludge by condensation, onto the powder particles, of microbe flocks that constitute the sludge. As a result, the magnets inside the drum magnetically attract the sludge onto the outer surface of the drum.

  9. Microgravity

    NASA Image and Video Library

    1998-10-10

    Dr. Harry Mahtani analyzes the gas content of nutrient media from Bioreactor used in research on human breast cancer. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues.

  10. Rotating microgravity-bioreactor cultivation enhances the hepatic differentiation of mouse embryonic stem cells on biodegradable polymer scaffolds.

    PubMed

    Wang, Yingjie; Zhang, Yunping; Zhang, Shichang; Peng, Guangyong; Liu, Tao; Li, Yangxin; Xiang, Dedong; Wassler, Michael J; Shelat, Harnath S; Geng, Yongjian

    2012-11-01

    Embryonic stem (ES) cells are pluripotent cells that are capable of differentiating all the somatic cell lineages, including those in the liver tissue. We describe the generation of functional hepatic-like cells from mouse ES (mES) cells using a biodegradable polymer scaffold and a rotating bioreactor that allows simulated microgravity. Cells derived from ES cells cultured in the three-dimensional (3D) culture system with exogenous growth factors and hormones can differentiate into hepatic-like cells with morphologic characteristics of typical mature hepatocytes. Reverse-transcription polymerase chain-reaction testing, Western blot testing, immunostaining, and flow cytometric analysis show that these cells express hepatic-specific genes and proteins during differentiation. Differentiated cells on scaffolds further exhibit morphologic traits and biomarkers characteristic of liver cells, including albumin production, cytochrome P450 activity, and low-density lipoprotein uptake. When these stem cell-bearing scaffolds are transplanted into severe combined immunodeficient mice, the 3D constructs remained viable, undergoing further differentiation and maturation of hepatic-like cells in vivo. In conclusion, the growth and differentiation of ES cells in a biodegradable polymer scaffold and a rotating microgravity bioreactor can yield functional and organizational hepatocytes useful for research involving bioartificial liver and engineered liver tissue.

  11. Microgravity

    NASA Image and Video Library

    1998-10-10

    High magnification of view of tumor cells aggregate on microcarrier beads, illustrting breast cells with intercellular boundaires on bead surface and aggregates of cells achieving 3-deminstional growth outward from bead after 56 days of culture in a NASA Bioreactor. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Jearne Becker, University of South Florida.

  12. Microgravity

    NASA Image and Video Library

    1998-10-10

    High magnification view of human primary breast tumor cells after 56 days of culture in a NASA Bioreactor. The arrow points to bead surface indicating breast cancer cells (as noted by the staining of tumor cell intermediate filaments). NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Jearne Becker, University of South Florida

  13. Bioreactor and methods for producing synchronous cells

    NASA Technical Reports Server (NTRS)

    Helmstetter, Charles E. (Inventor); Thornton, Maureen (Inventor); Gonda, Steve (Inventor)

    2005-01-01

    Apparatus and methods are directed to a perfusion culture system in which a rotating bioreactor is used to grow cells in a liquid culture medium, while these cells are attached to an adhesive-treated porous surface. As a result of this arrangement and its rotation, the attached cells divide, with one cell remaining attached to the substrate, while the other cell, a newborn cell is released. These newborn cells are of approximately the same age, that are collected upon leaving the bioreactor. The populations of newborn cells collected are of synchronous and are minimally, if at all, disturbed metabolically.

  14. Fabrication, characterization, and in vitro evaluation of poly(lactic acid glycolic acid)/nano-hydroxyapatite composite microsphere-based scaffolds for bone tissue engineering in rotating bioreactors.

    PubMed

    Lv, Qing; Nair, Lakshmi; Laurencin, Cato T

    2009-12-01

    Dynamic flow culture bioreactor systems have been shown to enhance in vitro bone tissue formation by facilitating mass transfer and providing mechanical stimulation. Our laboratory has developed a biodegradable poly (lactic acid glycolic acid) (PLAGA) mixed scaffold consisting of lighter-than-water (LTW) and heavier-than-water (HTW) microspheres as potential matrices for engineering tissue using a high aspect ratio vessel (HARV) rotating bioreactor system. We have demonstrated enhanced osteoblast differentiation and mineralization on PLAGA scaffolds in the HARV rotating bioreactor system when compared with static culture. The objective of the present study is to improve the mechanical properties and bioactivity of polymeric scaffolds by designing LTW polymer/ceramic composite scaffolds suitable for dynamic culture using a HARV bioreactor. We employed a microsphere sintering method to fabricate three-dimensional PLAGA/nano-hydroxyapatite (n-HA) mixed scaffolds composed of LTW and HTW composite microspheres. The mechanical properties, pore size and porosity of the composite scaffolds were controlled by varying parameters, such as sintering temperature, sintering time, and PLAGA/n-HA ratio. The PLAGA/n-HA (4:1) scaffold sintered at 90 degrees C for 3 h demonstrated the highest mechanical properties and an appropriate pore structure for bone tissue engineering applications. Furthermore, evaluation human mesenchymal stem cells (HMSCs) response to PLAGA/n-HA scaffolds was performed. HMSCs on PLAGA/n-HA scaffolds demonstrated enhanced proliferation, differentiation, and mineralization when compared with those on PLAGA scaffolds. Therefore, PLAGA/n-HA mixed scaffolds are promising candidates for HARV bioreactor-based bone tissue engineering applications. Copyright 2008 Wiley Periodicals, Inc.

  15. A novel buoyancy technique optimizes simulated microgravity conditions for whole sensory organ culture in rotating bioreactors.

    PubMed

    Arnold, Heinz J P; Müller, Marcus; Waldhaus, Jörg; Hahn, Hartmut; Löwenheim, Hubert

    2010-02-01

    Whole-organ culture of a sensory organ in a rotating wall vessel bioreactor provides a powerful in vitro model for physiological and pathophysiological investigation as previously demonstrated for the postnatal inner ear. The model is of specific relevance as a tool for regeneration research. In the immature inner ear explant, the density was only 1.29 g/cm(3). The high density of 1.68 g/cm(3) of the functionally mature organ resulted in enhanced settling velocity and deviation from its ideal circular orbital path causing enhanced shear stress. The morphometric and physical properties, as well as the dynamic motion patterns of explants, were analyzed and numerically evaluated by an orbital path index. Application of a novel buoyancy bead technique resulted in a 6.5- to 14.8-fold reduction of the settling velocity. The deviation of the explant from its ideal circular orbital path was adjusted as indicated by an optimum value for the orbital path index (-1.0). Shear stress exerted on the inner ear explant was consequently reduced 6.4- to 15.0-fold. The culture conditions for postnatal stages were optimized, and the preconditions for transferring this in vitro model toward mature high-density stages established. This buoyancy technique may also be useful in tissue engineering of other high-density structures.

  16. Advanced Wastewater Treatment Engineering—Investigating Membrane Fouling in both Rotational and Static Membrane Bioreactor Systems Using Empirical Modelling

    PubMed Central

    Paul, Parneet; Jones, Franck Anderson

    2016-01-01

    Advanced wastewater treatment using membranes are popular environmental system processes since they allow reuse and recycling. However, fouling is a key limiting factor and so proprietary systems such as Avanti’s RPU-185 Flexidisks membrane bioreactor (MBR) use novel rotating membranes to assist in ameliorating it. In earlier research, this rotating process was studied by creating a simulation model based on first principles and traditional fouling mechanisms. In order to directly compare the potential benefits of this rotational system, this follow-up study was carried out using Avanti’s newly developed static (non-rotating) Flexidisks MBR system. The results from operating the static pilot unit were simulated and modelled using the rotational fouling model developed earlier however with rotational switching functions turned off and rotational parameters set to a static mode. The study concluded that a rotating MBR system could increase flux throughput when compared against a similar static system. It is thought that although the slowly rotating spindle induces a weak crossflow shear, it is still able to even out cake build up across the membrane surface, thus reducing the likelihood of localised critical flux being exceeded at the micro level and lessening the potential of rapid trans-membrane pressure increases at the macro level. PMID:26742053

  17. Computational fluid modeling and performance analysis of a bidirectional rotating perfusion culture system.

    PubMed

    Kang, Chang-Wei; Wang, Yan; Tania, Marshella; Zhou, Huancheng; Gao, Yi; Ba, Te; Tan, Guo-Dong Sean; Kim, Sangho; Leo, Hwa Liang

    2013-01-01

    A myriad of bioreactor configurations have been investigated as extracorporeal medical support systems for temporary replacement of vital organ functions. In recent years, studies have demonstrated that the rotating bioreactors have the potential to be utilized as bioartificial liver assist devices (BLADs) owing to their advantage of ease of scalability of cell-culture volume. However, the fluid movement in the rotating chamber will expose the suspended cells to unwanted flow structures with abnormally high shear conditions that may result in poor cell stability and in turn lower the efficacy of the bioreactor system. In this study, we compared the hydrodynamic performance of our modified rotating bioreactor design with that of an existing rotating bioreactor design. Computational fluid dynamic analysis coupled with experimental results were employed in the optimization process for the development of the modified bioreactor design. Our simulation results showed that the modified bioreactor had lower fluid induced shear stresses and more uniform flow conditions within its rotating chamber than the conventional design. Experimental results revealed that the cells within the modified bioreactor also exhibited better cell-carrier attachment, higher metabolic activity, and cell viability compared to those in the conventional design. In conclusion, this study was able to provide important insights into the flow physics within the rotating bioreactors, and help enhanced the hydrodynamic performance of an existing rotating bioreactor for BLAD applications. © 2013 American Institute of Chemical Engineers.

  18. Use of NASA Bioreactor in Engineering Tissue for Bone Repair

    NASA Technical Reports Server (NTRS)

    Duke, Pauline

    1998-01-01

    This study was proposed in search for a new alternative for bone replacement or repair. Because the systems commonly used in repair of bony defects form bone by going through a cartilaginous phase, implantation of a piece of cartilage could enhance the healing process by having a more advanced starting point. However, cartilage has seldom been used to replace bone due, in part, to the limitations in conventional culture systems that did not allow production of enough tissue for implants. The NASA-developed bioreactors known as STLV (Slow Turning Lateral Vessel) provide homogeneous distribution of cells, nutrients, and waste products, with less damaging turbulence and shear forces than conventional systems. Cultures under these conditions have higher growth rates, viability, and longevity, allowing larger "tissue-like" aggregates to form, thus opening the possibilities of producing enough tissue for implantation, along with the inherent advantages of in vitro manipulations. To assure large numbers of cells and to eliminate the use of timed embryos, we proposed to use an immortalized mouse limb bud cell line as the source of cells.

  19. Mechanobiologic Research in a Microgravity Environment Bioreactor

    NASA Astrophysics Data System (ADS)

    Guidi, A.; Dubini, G.; Tominetti, F.; Raimondi, M.

    Rotating Wall Vessel developed by NASA, and originally designed to protect cell culture from the high shear forces generated during the launch and the landing of the Space Shuttle. A Bioreactor that is used both for ground and flight experiments provides the additional benefit of isolating dependent variable of gravity. This continuity will provide a means to compare results to a control experiment.

  20. Laminar boundary layer near the rotating end wall of a confined vortex

    NASA Astrophysics Data System (ADS)

    Shakespeare, W. J.; Levy, E. K.

    1982-06-01

    The results of an experimental and theoretical investigation of the fluid mechanics in a confined vortex are discussed with particular emphasis on behavior away from the axis of symmetry and near the end walls. The vortex is generated in a rotating cylindrical chamber with an exit opening in one end. Both end walls rotate. For the range of flow rates and swirl ratios (S between 1 and 5) of interest here, the flow field far from the end walls behaves as inviscid and irrotational; and the end wall boundary layers are thin and laminar. Measurements and calculations of tangential and radial velocity in the end wall region show the development of a secondary flow resulting in a strong velocity 'overshoot' in the radial component. Results illustrating the nature of the velocity variations on the end walls are presented; and it is shown that the mass flow rate through the end wall boundary layers, while only a small fraction of the total flow, increases with increasing swirl and with decreasing total flow rate through the chamber.

  1. Use of microgravity bioreactors for development of an in vitro rat salivary gland cell culture model

    NASA Technical Reports Server (NTRS)

    Lewis, M. L.; Moriarity, D. M.; Campbell, P. S.

    1993-01-01

    During development, salivary gland (SG) cells both secrete factors which modulate cellular behavior and express specific hormone receptors. Whether SG cell growth is modulated by an autocrine epidermal growth factor (EGF) receptor-mediated signal transduction pathway is not clearly understood. SG tissue is the synthesis site for functionally distinct products including growth factors, digestive enzymes, and homeostasis maintaining factors. Historically, SG cells have proven difficult to grow and may be only maintained as limited three-dimensional ductal-type structures in collagen gels or on reconstituted basement membrane gels. A novel approach to establishing primary rat SG cultures is use of microgravity bioreactors originally designed by NASA as low-shear culture systems for predicting cell growth and differentiation in the microgravity environment of space. These completely fluid-filled bioreactors, which are oriented horizontally and rotate, have proven advantageous for Earth-based culture of three-dimensional cell assemblies, tissue-like aggregates, and glandular structures. Use of microgravity bioreactors for establishing in vitro models to investigate steroid-mediated secretion of EGF by normal SG cells may also prove useful for the investigation of cancer and other salivary gland disorders. These microgravity bioreactors promise challenging opportunities for future applications in basic and applied cell research.

  2. Microgravity

    NASA Image and Video Library

    1996-01-01

    Electronics control module for the NASA Bioreactor. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  3. Microgravity

    NASA Image and Video Library

    1996-01-01

    Interior view of the gas supply for the NASA Bioreactor. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  4. Turbulence modeling: Near-wall turbulence and effects of rotation on turbulence

    NASA Technical Reports Server (NTRS)

    Shih, T.-H.

    1990-01-01

    Many Reynolds averaged Navier-Stokes solvers use closure models in conjunction with 'the law of the wall', rather than deal with a thin, viscous sublayer near the wall. This work is motivated by the need for better models to compute near wall turbulent flow. The authors use direct numerical simulation of fully developed channel flow and one of three dimensional turbulent boundary layer flow to develop new models. These direct numerical simulations provide detailed data that experimentalists have not been able to measure directly. Another objective of the work is to examine analytically the effects of rotation on turbulence, using Rapid Distortion Theory (RDT). This work was motivated by the observation that the pressure strain models in all current second order closure models are unable to predict the effects of rotation on turbulence.

  5. Microgravity

    NASA Image and Video Library

    2001-05-31

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells.

  6. The bacterial actin MreB rotates, and rotation depends on cell-wall assembly

    PubMed Central

    van Teeffelen, Sven; Wang, Siyuan; Furchtgott, Leon; Huang, Kerwyn Casey; Wingreen, Ned S.; Shaevitz, Joshua W.; Gitai, Zemer

    2011-01-01

    Bacterial cells possess multiple cytoskeletal proteins involved in a wide range of cellular processes. These cytoskeletal proteins are dynamic, but the driving forces and cellular functions of these dynamics remain poorly understood. Eukaryotic cytoskeletal dynamics are often driven by motor proteins, but in bacteria no motors that drive cytoskeletal motion have been identified to date. Here, we quantitatively study the dynamics of the Escherichia coli actin homolog MreB, which is essential for the maintenance of rod-like cell shape in bacteria. We find that MreB rotates around the long axis of the cell in a persistent manner. Whereas previous studies have suggested that MreB dynamics are driven by its own polymerization, we show that MreB rotation does not depend on its own polymerization but rather requires the assembly of the peptidoglycan cell wall. The cell-wall synthesis machinery thus either constitutes a novel type of extracellular motor that exerts force on cytoplasmic MreB, or is indirectly required for an as-yet-unidentified motor. Biophysical simulations suggest that one function of MreB rotation is to ensure a uniform distribution of new peptidoglycan insertion sites, a necessary condition to maintain rod shape during growth. These findings both broaden the view of cytoskeletal motors and deepen our understanding of the physical basis of bacterial morphogenesis. PMID:21903929

  7. The bacterial actin MreB rotates, and rotation depends on cell-wall assembly.

    PubMed

    van Teeffelen, Sven; Wang, Siyuan; Furchtgott, Leon; Huang, Kerwyn Casey; Wingreen, Ned S; Shaevitz, Joshua W; Gitai, Zemer

    2011-09-20

    Bacterial cells possess multiple cytoskeletal proteins involved in a wide range of cellular processes. These cytoskeletal proteins are dynamic, but the driving forces and cellular functions of these dynamics remain poorly understood. Eukaryotic cytoskeletal dynamics are often driven by motor proteins, but in bacteria no motors that drive cytoskeletal motion have been identified to date. Here, we quantitatively study the dynamics of the Escherichia coli actin homolog MreB, which is essential for the maintenance of rod-like cell shape in bacteria. We find that MreB rotates around the long axis of the cell in a persistent manner. Whereas previous studies have suggested that MreB dynamics are driven by its own polymerization, we show that MreB rotation does not depend on its own polymerization but rather requires the assembly of the peptidoglycan cell wall. The cell-wall synthesis machinery thus either constitutes a novel type of extracellular motor that exerts force on cytoplasmic MreB, or is indirectly required for an as-yet-unidentified motor. Biophysical simulations suggest that one function of MreB rotation is to ensure a uniform distribution of new peptidoglycan insertion sites, a necessary condition to maintain rod shape during growth. These findings both broaden the view of cytoskeletal motors and deepen our understanding of the physical basis of bacterial morphogenesis.

  8. Some process control/design considerations in the development of a microgravity mammalian cell bioreactor

    NASA Technical Reports Server (NTRS)

    Goochee, Charles F.

    1987-01-01

    The purpose is to review some of the physical/metabolic factors which must be considered in the development of an operating strategy for a mammalian cell bioreactor. Emphasis is placed on the dissolved oxygen and carbon dioxide requirements of growing mammalian epithelial cells. Literature reviews concerning oxygen and carbon dioxide requirements are discussed. A preliminary, dynamic model which encompasses the current features of the NASA bioreactor is presented. The implications of the literature survey and modeling effort on the design and operation of the NASA bioreactor are discussed.

  9. Microgravity

    NASA Image and Video Library

    1998-10-10

    Human primary breast tumor cells after 56 days of culture in a NASA Bioreactor. A cross-section of a construct, grown from surgical specimens of brease cancer, stained for microscopic examination, reveals areas of tumor cells dispersed throughout the non-epithelial cell background. The arrow denotes the foci of breast cancer cells. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Jearne Becker, University of South Florida

  10. Microgravity

    NASA Image and Video Library

    1996-01-01

    Laptop computer sits atop the Experiment Control Computer for a NASA Bioreactor. The flight crew can change operating conditions in the Bioreactor by using the graphical interface on the laptop. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  11. RodZ links MreB to cell wall synthesis to mediate MreB rotation and robust morphogenesis

    PubMed Central

    Morgenstein, Randy M.; Bratton, Benjamin P.; Nguyen, Jeffrey P.; Ouzounov, Nikolay; Shaevitz, Joshua W.; Gitai, Zemer

    2015-01-01

    The rod shape of most bacteria requires the actin homolog, MreB. Whereas MreB was initially thought to statically define rod shape, recent studies found that MreB dynamically rotates around the cell circumference dependent on cell wall synthesis. However, the mechanism by which cytoplasmic MreB is linked to extracytoplasmic cell wall synthesis and the function of this linkage for morphogenesis has remained unclear. Here we demonstrate that the transmembrane protein RodZ mediates MreB rotation by directly or indirectly coupling MreB to cell wall synthesis enzymes. Furthermore, we map the RodZ domains that link MreB to cell wall synthesis and identify mreB mutants that suppress the shape defect of ΔrodZ without restoring rotation, uncoupling rotation from rod-like growth. Surprisingly, MreB rotation is dispensable for rod-like shape determination under standard laboratory conditions but is required for the robustness of rod shape and growth under conditions of cell wall stress. PMID:26396257

  12. RodZ links MreB to cell wall synthesis to mediate MreB rotation and robust morphogenesis.

    PubMed

    Morgenstein, Randy M; Bratton, Benjamin P; Nguyen, Jeffrey P; Ouzounov, Nikolay; Shaevitz, Joshua W; Gitai, Zemer

    2015-10-06

    The rod shape of most bacteria requires the actin homolog, MreB. Whereas MreB was initially thought to statically define rod shape, recent studies found that MreB dynamically rotates around the cell circumference dependent on cell wall synthesis. However, the mechanism by which cytoplasmic MreB is linked to extracytoplasmic cell wall synthesis and the function of this linkage for morphogenesis has remained unclear. Here we demonstrate that the transmembrane protein RodZ mediates MreB rotation by directly or indirectly coupling MreB to cell wall synthesis enzymes. Furthermore, we map the RodZ domains that link MreB to cell wall synthesis and identify mreB mutants that suppress the shape defect of ΔrodZ without restoring rotation, uncoupling rotation from rod-like growth. Surprisingly, MreB rotation is dispensable for rod-like shape determination under standard laboratory conditions but is required for the robustness of rod shape and growth under conditions of cell wall stress.

  13. Reduced critical rotation for resistive-wall mode stabilization in a near-axisymmetric configuration.

    PubMed

    Reimerdes, H; Garofalo, A M; Jackson, G L; Okabayashi, M; Strait, E J; Chu, M S; In, Y; La Haye, R J; Lanctot, M J; Liu, Y Q; Navratil, G A; Solomon, W M; Takahashi, H; Groebner, R J

    2007-02-02

    Recent DIII-D experiments with reduced neutral beam torque and minimum nonaxisymmetric perturbations of the magnetic field show a significant reduction of the toroidal plasma rotation required for the stabilization of the resistive-wall mode (RWM) below the threshold values observed in experiments that apply nonaxisymmetric magnetic fields to slow the plasma rotation. A toroidal rotation frequency of less than 10 krad/s at the q=2 surface (measured with charge exchange recombination spectroscopy using C VI) corresponding to 0.3% of the inverse of the toroidal Alfvén time is sufficient to sustain the plasma pressure above the ideal MHD no-wall stability limit. The low-rotation threshold is found to be consistent with predictions by a kinetic model of RWM damping.

  14. Process technology of luwak coffee through bioreactor utilization

    NASA Astrophysics Data System (ADS)

    Hadipernata, M.; Nugraha, S.

    2018-01-01

    Indonesia has an advantage in producing exotic coffee that is Luwak coffee. Luwak coffee is produced from the fermentation process in digestion of civet. Luwak coffee production is still limited due to the difficulty level in the use of civet animals as the only medium of Luwak coffee making. The research was conducted by developing technology of luwak coffee production through bioreactor utilization and addition the bacteria isolate from gastric of civet. The process conditions in the bioreactor which include temperature, pH, and bacteria isolate of civet are adjusted to the process that occurs in civet digestion, including peristaltic movement on the stomach and small intestine of the civet will be replaced by the use of propellers that rotate on the bioreactor. The result of research showed that proximat analysis data of artificial/bioreactor luwak coffee did not significant different with original luwak coffee. However, the original luwak coffee has higher content of caffeine compared to bioreactor luwak coffee. Based on the cuping test the bioreactor luwak coffee has a value of 84.375, while the original luwak coffee is 84.875. As the result, bioreactor luwak coffee has excellent taste that similiar with original luwak coffee taste.

  15. Calculation of ground state rotational populations for kinetic gas homonuclear diatomic molecules including electron-impact excitation and wall collisions.

    PubMed

    Farley, David R

    2010-09-07

    A model has been developed to calculate the ground state rotational populations of homonuclear diatomic molecules in kinetic gases, including the effects of electron-impact excitation, wall collisions, and gas feed rate. The equations are exact within the accuracy of the cross sections used and of the assumed equilibrating effect of wall collisions. It is found that the inflow of feed gas and equilibrating wall collisions can significantly affect the rotational distribution in competition with nonequilibrating electron-impact effects. The resulting steady-state rotational distributions are generally Boltzmann for N≥3, with a rotational temperature between the wall and feed gas temperatures. The N=0,1,2 rotational level populations depend sensitively on the relative rates of electron-impact excitation versus wall collision and gas feed rates.

  16. Microgravity

    NASA Image and Video Library

    1996-01-01

    Interior of a Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  17. Microgravity

    NASA Image and Video Library

    1996-01-01

    Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell and with thermal blankets partially removed. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  18. Microgravity

    NASA Image and Video Library

    1996-01-01

    Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  19. Control of linear modes in cylindrical resistive magnetohydrodynamics with a resistive wall, plasma rotation, and complex gain

    NASA Astrophysics Data System (ADS)

    Brennan, D. P.; Finn, J. M.

    2014-10-01

    Feedback stabilization of magnetohydrodynamic (MHD) modes in a tokamak is studied in a cylindrical model with a resistive wall, plasma resistivity, viscosity, and toroidal rotation. The control is based on a linear combination of the normal and tangential components of the magnetic field just inside the resistive wall. The feedback includes complex gain, for both the normal and for the tangential components, and it is known that the imaginary part of the feedback for the former is equivalent to plasma rotation [J. M. Finn and L. Chacon, Phys. Plasmas 11, 1866 (2004)]. The work includes (1) analysis with a reduced resistive MHD model for a tokamak with finite β and with stepfunction current density and pressure profiles, and (2) computations with a full compressible visco-resistive MHD model with smooth decreasing profiles of current density and pressure. The equilibria are stable for β = 0 and the marginal stability values βrp,rw < βrp,iw < βip,rw < βip,iw (resistive plasma, resistive wall; resistive plasma, ideal wall; ideal plasma, resistive wall; and ideal plasma, ideal wall) are computed for both models. The main results are: (a) imaginary gain with normal sensors or plasma rotation stabilizes below βrp,iw because rotation suppresses the diffusion of flux from the plasma out through the wall and, more surprisingly, (b) rotation or imaginary gain with normal sensors destabilizes above βrp,iw because it prevents the feedback flux from entering the plasma through the resistive wall to form a virtual wall. A method of using complex gain Gi to optimize in the presence of rotation in this regime with β > βrp,iw is presented. The effect of imaginary gain with tangential sensors is more complicated but essentially destabilizes above and below βrp,iw.

  20. Ex vivo blood vessel bioreactor for analysis of the biodegradation of magnesium stent models with and without vessel wall integration.

    PubMed

    Wang, Juan; Liu, Lumei; Wu, Yifan; Maitz, Manfred F; Wang, Zhihong; Koo, Youngmi; Zhao, Ansha; Sankar, Jagannathan; Kong, Deling; Huang, Nan; Yun, Yeoheung

    2017-03-01

    Current in vitro models fail in predicting the degradation rate and mode of magnesium (Mg) stents in vivo. To overcome this, the microenvironment of the stent is simulated here in an ex vivo bioreactor with porcine aorta and circulating medium, and compared with standard static in vitro immersion and with in vivo rat aorta models. In ex vivo and in vivo conditions, pure Mg wires were exposed to the aortic lumen and inserted into the aortic wall to mimic early- and long-term implantation, respectively. Results showed that: 1) Degradation rates of Mg were similar for all the fluid diffusion conditions (in vitro static, aortic wall ex vivo and in vivo); however, Mg degradation under flow condition (i.e. in the lumen) in vivo was slower than ex vivo; 2) The corrosion mode in the samples can be mainly described as localized (in vitro), mixed localized and uniform (ex vivo), and uniform (in vivo); 3) Abundant degradation products (MgO/Mg(OH) 2 and Ca/P) with gas bubbles accumulated around the localized degradation regions ex vivo, but a uniform and thin degradation product layer was found in vivo. It is concluded that the ex vivo vascular bioreactor provides an improved test setting for magnesium degradation between static immersion and animal experiments and highlights its promising role in bridging degradation behavior and biological response for vascular stent research. Magnesium and its alloys are candidates for a new generation of biodegradable stent materials. However, the in vitro degradation of magnesium stents does not match the clinical degradation rates, corrupting the validity of conventional degradation tests. Here we report an ex vivo vascular bioreactor, which allows simulation of the microenvironment with and without blood vessel integration to study the biodegradation of magnesium implants in comparison with standard in vitro test conditions and with in vivo implantations. The bioreactor did simulate the corrosion of an intramural implant very well, but

  1. An Optical Oxygen Sensor for Long-Term Continuous Monitoring of Dissolved Oxygen in Perfused Bioreactors

    NASA Technical Reports Server (NTRS)

    Gao, F. G.; Jeevarajan, A. S.; Anderson, M. M.

    2002-01-01

    acquire data. Two HOXY sensors with a single calibration were employed to continuously monitor the DO in GTSF-2 medium during a Baby Hamster Kidney (BHK-21) cell culture in a Rotating Wall Perfused Vessel (RWPV) bioreactor for 90 days. HOXY sensors were located at the inlet to and outlet from the bioreactor. One of the sensors was placed between an oxygenator and the inlet to the bioreactor. The dissolved oxygen concentrations determined by both sensors were compared with those measured regularly with the BGA reference. The cell culture was maintained for 110 days. Sensor output was found to correlate well with the BGA data throughout the experiment, where the DO of the medium ranged between 25 and 50 mmHg at the bioreactor outlet and 90-130 mmHg at the bioreactor inlet. Measuring DO with the HOXY sensors versus the BGA reference indicated bias values of -2 mmHg and -15 mmHg, and precision values of +/-3mmHg and +/-16 mmHg at the bioreactor inlet and outlet, respectively.

  2. Microgravity

    NASA Image and Video Library

    1998-10-10

    Breast tissue specimens in traditional sample dishes. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues.

  3. Distribution and Viability of Fetal and Adult Human Bone Marrow Stromal Cells in a Biaxial Rotating Vessel Bioreactor after Seeding on Polymeric 3D Additive Manufactured Scaffolds

    PubMed Central

    Leferink, Anne M.; Chng, Yhee-Cheng; van Blitterswijk, Clemens A.; Moroni, Lorenzo

    2015-01-01

    One of the conventional approaches in tissue engineering is the use of scaffolds in combination with cells to obtain mechanically stable tissue constructs in vitro prior to implantation. Additive manufacturing by fused deposition modeling is a widely used technique to produce porous scaffolds with defined pore network, geometry, and therewith defined mechanical properties. Bone marrow-derived mesenchymal stromal cells (MSCs) are promising candidates for tissue engineering-based cell therapies due to their multipotent character. One of the hurdles to overcome when combining additive manufactured scaffolds with MSCs is the resulting heterogeneous cell distribution and limited cell proliferation capacity. In this study, we show that the use of a biaxial rotating bioreactor, after static culture of human fetal MSCs (hfMSCs) seeded on synthetic polymeric scaffolds, improved the homogeneity of cell and extracellular matrix distribution and increased the total cell number. Furthermore, we show that the relative mRNA expression levels of indicators for stemness and differentiation are not significantly changed upon this bioreactor culture, whereas static culture shows variations of several indicators for stemness and differentiation. The biaxial rotating bioreactor presented here offers a homogeneous distribution of hfMSCs, enabling studies on MSCs fate in additive manufactured scaffolds without inducing undesired differentiation. PMID:26557644

  4. Distribution and Viability of Fetal and Adult Human Bone Marrow Stromal Cells in a Biaxial Rotating Vessel Bioreactor after Seeding on Polymeric 3D Additive Manufactured Scaffolds.

    PubMed

    Leferink, Anne M; Chng, Yhee-Cheng; van Blitterswijk, Clemens A; Moroni, Lorenzo

    2015-01-01

    One of the conventional approaches in tissue engineering is the use of scaffolds in combination with cells to obtain mechanically stable tissue constructs in vitro prior to implantation. Additive manufacturing by fused deposition modeling is a widely used technique to produce porous scaffolds with defined pore network, geometry, and therewith defined mechanical properties. Bone marrow-derived mesenchymal stromal cells (MSCs) are promising candidates for tissue engineering-based cell therapies due to their multipotent character. One of the hurdles to overcome when combining additive manufactured scaffolds with MSCs is the resulting heterogeneous cell distribution and limited cell proliferation capacity. In this study, we show that the use of a biaxial rotating bioreactor, after static culture of human fetal MSCs (hfMSCs) seeded on synthetic polymeric scaffolds, improved the homogeneity of cell and extracellular matrix distribution and increased the total cell number. Furthermore, we show that the relative mRNA expression levels of indicators for stemness and differentiation are not significantly changed upon this bioreactor culture, whereas static culture shows variations of several indicators for stemness and differentiation. The biaxial rotating bioreactor presented here offers a homogeneous distribution of hfMSCs, enabling studies on MSCs fate in additive manufactured scaffolds without inducing undesired differentiation.

  5. A Good Neighborhood for Cells: Bioreactor Demonstration System (BDS-05)

    NASA Technical Reports Server (NTRS)

    Chung, Leland W. K.; Goodwin, Thomas J. (Technical Monitor)

    2002-01-01

    Good neighborhoods help you grow. As with a city, the lives of a cell are governed by its neighborhood connections Connections that do not work are implicated in a range of diseases. One of those connections - between prostate cancer and bone cells - will be studied on STS-107 using the Bioreactor Demonstration System (BDS-05). To improve the prospects for finding novel therapies, and to identify biomarkers that predict disease progression, scientists need tissue models that behave the same as metastatic or spreading cancer. This is one of several NASA-sponsored lines of cell science research that use the microgravity environment of orbit in an attempt to grow lifelike tissue models for health research. As cells replicate, they "self associate" to form a complex matrix of collagens, proteins, fibers, and other structures. This highly evolved microenvironment tells each cell who is next door, how it should grow arid into what shapes, and how to respond to bacteria, wounds, and other stimuli. Studying these mechanisms outside the body is difficult because cells do not easily self-associate outside a natural environment. Most cell cultures produce thin, flat specimens that offer limited insight into how cells work together. Ironically, growing cell cultures in the microgravity of space produces cell assemblies that more closely resemble what is found in bodies on Earth. NASA's Bioreactor comprises a miniature life support system and a rotating vessel containing cell specimens in a nutrient medium. Orbital BDS experiments that cultured colon and prostate cancers have been highly promising.

  6. Synergistic Effects of Incubation in Rotating Bioreactors and Cumulative Low Dose 60Co γ-ray Irradiation on Human Immortal Lymphoblastoid Cells

    NASA Astrophysics Data System (ADS)

    Wei, Lijun; Han, Fang; Yue, Lei; Zheng, Hongxia; Yu, Dan; Ma, Xiaohuan; Cheng, Huifang; Li, Yu

    2012-11-01

    The complex space environments can influence cell structure and function. The research results on space biology have shown that the major mutagenic factors in space are microgravity and ionizing radiation. In addition, possible synergistic effects of radiation and microgravity on human cells are not well understood. In this study, human immortal lymphoblastoid cells were established from human peripheral blood lymphocytes and the cells were treated with low dose (0.1, 0.15 and 0.2 Gy) cumulative 60Co γ-irradiation and simulated weightlessness [obtained by culturing cells in the Rotating Cell Culture System (RCCS)]. The commonly used indexes of cell damage such as micronucleus rate, cell cycle and mitotic index were studied. Previous work has proved that Gadd45 (growth arrest and DNA-damage-inducible protein 45) gene increases with a dose-effect relationship, and will possibly be a new biological dosimeter to show irradiation damage. So Gadd45 expression is also detected in this study. The micronucleus rate and the expression of Gadd45α gene increased with irradiation dose and were much higher after incubation in the rotating bioreactor than that in the static irradiation group, while the cell proliferation after incubation in the rotating bioreactor decreased at the same time. These results indicate synergetic effects of simulated weightlessness and low dose irradiation in human cells. The cell damage inflicted by γ-irradiation increased under simulated weightlessness. Our results suggest that during medium- and long-term flight, the human body can be damaged by cumulative low dose radiation, and the damage will even be increased by microgravity in space.

  7. Lymphocyte trafficking and HIV infection of human lymphoid tissue in a rotating wall vessel bioreactor

    NASA Technical Reports Server (NTRS)

    Margolis, L. B.; Fitzgerald, W.; Glushakova, S.; Hatfill, S.; Amichay, N.; Baibakov, B.; Zimmerberg, J.

    1997-01-01

    The pathogenesis of HIV infection involves a complex interplay between both the infected and noninfected cells of human lymphoid tissue, the release of free viral particles, the de novo infection of cells, and the recirculatory trafficking of peripheral blood lymphocytes. To develop an in vitro model for studying these various aspects of HIV pathogenesis we have utilized blocks of surgically excised human tonsils and a rotating wall vessel (RWV) cell culture system. Here we show that (1) fragments of the surgically excised human lymphoid tissue remain viable and retain their gross cytoarchitecture for at least 3 weeks when cultured in the RWV system; (2) such lymphoid tissue gradually shows a loss of both T and B cells to the surrounding growth medium; however, this cellular migration is reversible as demonstrated by repopulation of the tissue by labeled cells from the growth medium; (3) this cellular migration may be partially or completely inhibited by embedding the blocks of lymphoid tissue in either a collagen or agarose gel matrix; these embedded tissue blocks retain most of the basic elements of a normal lymphoid cytoarchitecture; and (4) both embedded and nonembedded RWV-cultured blocks of human lymphoid tissue are capable of productive infection by HIV-1 of at least three various strains of different tropism and phenotype, as shown by an increase in both p24 antigen levels and free virus in the culture medium, and by the demonstration of HIV-1 RNA-positive cells inside the tissue identified by in situ hybridization. It is therefore reasonable to suggest that gel-embedded and nonembedded blocks of human lymphoid tissue, cocultured with a suspension of tonsillar lymphocytes in an RWV culture system, constitute a useful model for simulating normal lymphocyte recirculatory traffic and provide a new tool for testing the various aspects of HIV pathogenesis.

  8. Biotechnology

    NASA Image and Video Library

    2001-05-15

    This prostate cancer construct was grown during NASA-sponsored bioreactor studies on Earth. Cells are attached to a biodegradable plastic lattice that gives them a head start in growth. Prostate tumor cells are to be grown in a NASA-sponsored Bioreactor experiment aboard the STS-107 Research-1 mission in 2002. Dr. Leland Chung of the University of Virginia is the principal investigator. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and the University of Virginia.

  9. Ex vivo blood vessel bioreactor for analysis of the biodegradation of magnesium stent models with and without vessel wall integration

    PubMed Central

    Wang, Juan; Liu, Lumei; Wu, Yifan; Maitz, Manfred F.; Wang, Zhihong; Koo, Youngmi; Zhao, Ansha; Sankar, Jagannathan; Kong, Deling; Huang, Nan; Yun, Yeoheung

    2017-01-01

    Current in vitro models fail in predicting the degradation rate and mode of magnesium (Mg) stents in vivo. To overcome this, the microenvironment of the stent is simulated here in an ex vivo bioreactor with porcine aorta and circulating medium, and compared with standard static in vitro immersion and with in vivo rat aorta models. In ex vivo and in vivo conditions, pure Mg wires were exposed to the aortic lumen and inserted into the aortic wall to mimic early- and long-term implantation, respectively. Results showed that: 1) Degradation rates of Mg were similar for all the fluid diffusion conditions (in vitro static, aortic wall ex vivo and in vivo); however, Mg degradation under flow condition (i.e. in the lumen) in vivo was slower than ex vivo; 2) The corrosion mode in the samples can be mainly described as localized (in vitro), mixed localized and uniform (ex vivo), and uniform (in vivo); 3) Abundant degradation products (MgO/Mg(OH)2 and Ca/P) with gas bubbles accumulated around the localized degradation regions ex vivo, but a uniform and thin degradation product layer was found in vivo. It is concluded that the ex vivo vascular bioreactor provides an improved test setting for magnesium degradation between static immersion and animal experiments and highlights its promising role in bridging degradation behavior and biological response for vascular stent research. PMID:28013101

  10. Biotechnology

    NASA Image and Video Library

    2002-07-02

    Leland W. K. Chung (left), Director, Molecular Urology Therapeutics Program at the Winship Cancer Institute at Emory University, is principal investigator for the NASA bioreactor demonstration system (BDS-05). With him is Dr. Jun Shu, an assistant professor of Orthopedics Surgery from Kuming Medical University China. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  11. Control of linear modes in cylindrical resistive magnetohydrodynamics with a resistive wall, plasma rotation, and complex gain

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brennan, D. P.; Finn, J. M.

    2014-10-15

    Feedback stabilization of magnetohydrodynamic (MHD) modes in a tokamak is studied in a cylindrical model with a resistive wall, plasma resistivity, viscosity, and toroidal rotation. The control is based on a linear combination of the normal and tangential components of the magnetic field just inside the resistive wall. The feedback includes complex gain, for both the normal and for the tangential components, and it is known that the imaginary part of the feedback for the former is equivalent to plasma rotation [J. M. Finn and L. Chacon, Phys. Plasmas 11, 1866 (2004)]. The work includes (1) analysis with a reducedmore » resistive MHD model for a tokamak with finite β and with stepfunction current density and pressure profiles, and (2) computations with a full compressible visco-resistive MHD model with smooth decreasing profiles of current density and pressure. The equilibria are stable for β = 0 and the marginal stability values β{sub rp,rw} < β{sub rp,iw} < β{sub ip,rw} < β{sub ip,iw} (resistive plasma, resistive wall; resistive plasma, ideal wall; ideal plasma, resistive wall; and ideal plasma, ideal wall) are computed for both models. The main results are: (a) imaginary gain with normal sensors or plasma rotation stabilizes below β{sub rp,iw} because rotation suppresses the diffusion of flux from the plasma out through the wall and, more surprisingly, (b) rotation or imaginary gain with normal sensors destabilizes above β{sub rp,iw} because it prevents the feedback flux from entering the plasma through the resistive wall to form a virtual wall. A method of using complex gain G{sub i} to optimize in the presence of rotation in this regime with β > β{sub rp,iw} is presented. The effect of imaginary gain with tangential sensors is more complicated but essentially destabilizes above and below β{sub rp,iw}.« less

  12. Analysis of gravity-induced particle motion and fluid perfusion flow in the NASA-designed rotating zero-head-space tissue culture vessel

    NASA Technical Reports Server (NTRS)

    Wolf, David A.; Schwarz, Ray P.

    1991-01-01

    The gravity induced motions, through the culture media, is calculated of living tissue segments cultured in the NASA rotating zero head space culture vessels. This is then compared with the media perfusion speed which is independent of gravity. The results may be interpreted as a change in the physical environment which will occur by operating the NASA tissue culture systems in actual microgravity (versus unit gravity). The equations governing particle motions which induce flows at the surface of tissues contain g terms. This allows calculation of the fluid flow speed, with respect to a cultured particle, as a function of the external gravitational field strength. The analysis is approached from a flow field perspective. Flow is proportional to the shear exerted on a structure which maintains position within the field. The equations are solved for the deviation of a particle from its original position in a circular streamline as a function of time. The radial deviation is important for defining the operating limits and dimensions of the vessel because of the finite radius at which particles necessarily intercept the wall. This analysis uses a rotating reference frame concept.

  13. Characterization of Flow and Ohm's Law in the Rotating Wall Machine

    NASA Astrophysics Data System (ADS)

    Hannum, David; Brookhart, M.; Forest, C. B.; Kendrick, R.; Mengin, G.; Paz-Soldan, C.

    2010-11-01

    The rotating wall machine is a linear screw-pinch built to study the role of different electromagnetic boundary conditions on the Resistive Wall Mode (RWM). Its plasma is created by an array of electrostatic washer guns which can be biased to discharge up to 1 kA of current each. Individual flux ropes from the guns shear, merge, and expand into a 20 cm diameter, ˜1 m long plasma column. Langmuir (singletip) and tri-axial B-dot probes move throughout the column to measure radial and axial profiles of key plasma parameters. As the plasma current increases, more H2 fuel is ionized, raising ne to 5 x10^20 m-3 while Te stays at a constant 3 eV. The electron density expands to the wall while the current density (Jz) stays pinched to the central axis. E xB and diamagnetic drifts create radially and axially sheared plasma rotation. Plasma resistivity follows the Spitzer model in the core while exceeding it at the edge. These measurements improve the model used to predict the RWM growth rate.

  14. Tissue Culture in Microgravity

    NASA Technical Reports Server (NTRS)

    Pellis, Neal R.; Duray, Paul H.; Hatfill, Steven J.

    1997-01-01

    Attempts to simulate normal tissue micro-environments in vitro have been thwarted by the complexity and plasticity of the extracellular matrix, which is important in regulating cytoskeletal and nuclear matrix proteins. Gravity is one of the problems, tending to separate components that should be kept together. For space shuttle experiments, NASA engineers devised a double-walled rotating bioreactor, which is proving to be a useful tissue culture device on earth as well as in space.

  15. The Study of Leukocyte Functions in a Rotating Wall Vessel

    NASA Technical Reports Server (NTRS)

    Trial, JoAnn

    1998-01-01

    The objective of this study was to investigate the behavior of leukocytes under free-fall conditions in a rotating wall vessel. In such a vessel, the tendency of a cell to fall in response to gravity is opposed by the rotation of the vessel and the culture medium within, keeping the cells in suspension without fluid shear. Previous reports indicated that such functions as lymphocyte migration through collagen matrix or monocyte cytokine secretion are altered under these conditions, and these changes correlate with similar functional defects of cultured cells seen during spaceflight.

  16. Biotechnology

    NASA Image and Video Library

    2003-01-22

    Dr. Cheryl Nickerson of Tulane University is studying the effects of simulated low-g on a well-known pathogen, Salmonella typhimurium, a bacterium that causes two to four million cases of gastrointestinal illness in the United States each year. While most healthy people recover readily, S. typhimurium can kill people with weakened immune systems. Thus, a simple case of food poisoning could disrupt a space mission. Using the NASA rotating-wall bioreactor, Nickerson cultured S. typhimurium in modeled microgravity. Mice infected with the bacterium died an average of three days faster than the control mice, indicating that S. typhimurium's virulence was enhanced by the bioreactor. Earlier research showed that 3 percent of the genes were altered by exposure to the bioreactor. Nickerson's work earned her a 2001 Presidential Early Career Award for Scientists and Engineers.

  17. Dr. Cheryl Nickerson studies Salmonella in simulated low-g

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Dr. Cheryl Nickerson of Tulane University is studying the effects of simulated low-g on a well-known pathogen, Salmonella typhimurium, a bacterium that causes two to four million cases of gastrointestinal illness in the United States each year. While most healthy people recover readily, S. typhimurium can kill people with weakened immune systems. Thus, a simple case of food poisoning could disrupt a space mission. Using the NASA rotating-wall bioreactor, Nickerson cultured S. typhimurium in modeled microgravity. Mice infected with the bacterium died an average of three days faster than the control mice, indicating that S. typhimurium's virulence was enhanced by the bioreactor. Earlier research showed that 3 percent of the genes were altered by exposure to the bioreactor. Nickerson's work earned her a 2001 Presidential Early Career Award for Scientists and Engineers.

  18. Dr. Cheryl Nickerson studies Salmonella Typhimurium

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Dr. Cheryl Nickerson of Tulane University is studying the effects of simulated low-g on a well-known pathogen, Salmonella typhimurium, a bacterium that causes two to four million cases of gastrointestinal illness in the United States each year. While most healthy people recover readily, S. typhimurium can kill people with weakened immune systems. Thus, a simple case of food poisoning could disrupt a space mission. Using the NASA rotating-wall bioreactor, Nickerson cultured S. typhimurium in modeled microgravity. Mice infected with the bacterium died an average of three days faster than the control mice, indicating that S. typhimurium's virulence was enhanced by the bioreactor. Earlier research showed that 3 percent of the genes were altered by exposure to the bioreactor. Nickerson's work earned her a 2001 Presidential Early Career Award for Scientists and Engineers.

  19. Microgravity

    NASA Image and Video Library

    2001-06-01

    Cells cultured on Earth (left) typically settle quickly on the bottom of culture vessels due to gravity. In microgravity (right), cells remain suspended and aggregate to form three-dimensional tissue. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  20. Microgravity

    NASA Image and Video Library

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. Shown here, clusters of cells slowly spin inside a bioreactor. On Earth, the cells continually fall through the buffer medium and never hit bottom. In space, they are naturally suspended. Rotation ensures gentle stirring so waste is removed and fresh nutrient and oxygen are supplied. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  1. Human cell culture in a space bioreactor

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.

    1988-01-01

    Microgravity offers new ways of handling fluids, gases, and growing mammalian cells in efficient suspension cultures. In 1976 bioreactor engineers designed a system using a cylindrical reactor vessel in which the cells and medium are slowly mixed. The reaction chamber is interchangeable and can be used for several types of cell cultures. NASA has methodically developed unique suspension type cell and recovery apparatus culture systems for bioprocess technology experiments and production of biological products in microgravity. The first Space Bioreactor was designed for microprocessor control, no gaseous headspace, circulation and resupply of culture medium, and slow mixing in very low shear regimes. Various ground based bioreactors are being used to test reactor vessel design, on-line sensors, effects of shear, nutrient supply, and waste removal from continuous culture of human cells attached to microcarriers. The small Bioreactor is being constructed for flight experiments in the Shuttle Middeck to verify systems operation under microgravity conditions and to measure the efficiencies of mass transport, gas transfer, oxygen consumption and control of low shear stress on cells.

  2. Rotation in a reversed field pinch with active feedback stabilization of resistive wall modes

    NASA Astrophysics Data System (ADS)

    Cecconello, M.; Menmuir, S.; Brunsell, P. R.; Kuldkepp, M.

    2006-09-01

    Active feedback stabilization of multiple resistive wall modes (RWMs) has been successfully proven in the EXTRAP T2R reversed field pinch. One of the features of plasma discharges operated with active feedback stabilization, in addition to the prolongation of the plasma discharge, is the sustainment of the plasma rotation. Sustained rotation is observed both for the internally resonant tearing modes (TMs) and the intrinsic impurity oxygen ions. Good quantitative agreement between the toroidal rotation velocities of both is found: the toroidal rotation is characterized by an acceleration phase followed, after one wall time, by a deceleration phase that is slower than in standard discharges. The TMs and the impurity ions rotate in the same poloidal direction with also similar velocities. Poloidal and toroidal velocities have comparable amplitudes and a simple model of their radial profile reproduces the main features of the helical angular phase velocity. RWMs feedback does not qualitatively change the TMs behaviour and typical phenomena such as the dynamo and the 'slinky' are still observed. The improved sustainment of the plasma and TMs rotation occurs also when feedback only acts on internally non-resonant RWMs. This may be due to an indirect positive effect, through non-linear coupling between TMs and RWMs, of feedback on the TMs or to a reduced plasma-wall interaction affecting the plasma flow rotation. Electromagnetic torque calculations show that with active feedback stabilization the TMs amplitude remains well below the locking threshold condition for a thick shell. Finally, it is suggested that active feedback stabilization of RWMs and current profile control techniques can be employed simultaneously thus improving both the plasma duration and its confinement properties.

  3. Role of flexoelectric coupling in polarization rotations at the a-c domain walls in ferroelectric perovskites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cao, Ye; Chen, Long-Qing; Kalinin, Sergei V.

    Ferroelectric and ferroelastic domain walls play important roles in ferroelectric properties. However, their couplings with flexoelectricity have been less understood. Here, we applied phase-field simulation to investigate the flexoelectric coupling with ferroelectric a/c twin structures in lead ziconate titanate thin films. Local stress gradients were found to exist near twin walls that created both lateral and vertical electric fields through the flexoelectric effect, resulting in polarization inclinations from either horizontal or normal orientation, polarization rotation angles deviated from 90°, and consequently highly asymmetric a/c twin walls. Furthermore, by tuning the flexoelectric strengths in a reasonable range from first-principles calculations, wemore » found that the transverse flexoelectric coefficient has a larger influence on the polarization rotation than longitudinal and shear coefficients. And as polar rotations that commonly occur at compositional morphotropic phase boundaries contribute to the piezoelectric enhancement, this work calls for further exploration of alternative strain-engineered polar rotations via flexoelectricity in ferroelectric thin films.« less

  4. Role of flexoelectric coupling in polarization rotations at the a-c domain walls in ferroelectric perovskites

    DOE PAGES

    Cao, Ye; Chen, Long-Qing; Kalinin, Sergei V.

    2017-05-16

    Ferroelectric and ferroelastic domain walls play important roles in ferroelectric properties. However, their couplings with flexoelectricity have been less understood. Here, we applied phase-field simulation to investigate the flexoelectric coupling with ferroelectric a/c twin structures in lead ziconate titanate thin films. Local stress gradients were found to exist near twin walls that created both lateral and vertical electric fields through the flexoelectric effect, resulting in polarization inclinations from either horizontal or normal orientation, polarization rotation angles deviated from 90°, and consequently highly asymmetric a/c twin walls. Furthermore, by tuning the flexoelectric strengths in a reasonable range from first-principles calculations, wemore » found that the transverse flexoelectric coefficient has a larger influence on the polarization rotation than longitudinal and shear coefficients. And as polar rotations that commonly occur at compositional morphotropic phase boundaries contribute to the piezoelectric enhancement, this work calls for further exploration of alternative strain-engineered polar rotations via flexoelectricity in ferroelectric thin films.« less

  5. Diagram of Cell to Cell Communication

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  6. Biotechnology

    NASA Image and Video Library

    2002-07-02

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  7. Report on a NASA astrobiology institute-funded workshop without walls: stellar stoichiometry.

    PubMed

    Desch, Steven J; Young, Patrick A; Anbar, Ariel D; Hinkel, Natalie; Pagano, Michael; Truitt, Amanda; Turnbull, Margaret

    2014-04-01

    We report on the NASA Astrobiology Institute-funded Workshop Without Walls entitled "Stellar Stoichiometry," hosted by the "Follow the Elements" team at Arizona State University in April 2013. We describe several innovative practices we adopted that made effective use of the Workshop Without Walls videoconferencing format, including use of information technologies, assignment of scientific tasks before the workshop, and placement of graduate students in positions of authority. A companion article will describe the scientific results arising from the workshop. Our intention here is to suggest best practices for future Workshops Without Walls.

  8. Rotation and kinetic modifications of the tokamak ideal-wall pressure limit.

    PubMed

    Menard, J E; Wang, Z; Liu, Y; Bell, R E; Kaye, S M; Park, J-K; Tritz, K

    2014-12-19

    The impact of toroidal rotation, energetic ions, and drift-kinetic effects on the tokamak ideal wall mode stability limit is considered theoretically and compared to experiment for the first time. It is shown that high toroidal rotation can be an important destabilizing mechanism primarily through the angular velocity shear; non-Maxwellian fast ions can also be destabilizing, and drift-kinetic damping can potentially offset these destabilization mechanisms. These results are obtained using the unique parameter regime accessible in the spherical torus NSTX of high toroidal rotation speed relative to the thermal and Alfvén speeds and high kinetic pressure relative to the magnetic pressure. Inclusion of rotation and kinetic effects significantly improves agreement between measured and predicted ideal stability characteristics and may provide new insight into tearing mode triggering.

  9. Microgravity

    NASA Image and Video Library

    1998-10-10

    Dr. Robert Richmond extracts breast cell tissue from one of two liquid nitrogen dewars. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues.

  10. The rotation of cellulose synthase trajectories is microtubule dependent and influences the texture of epidermal cell walls in Arabidopsis hypocotyls.

    PubMed

    Chan, Jordi; Crowell, Elizabeth; Eder, Magdalena; Calder, Grant; Bunnewell, Susan; Findlay, Kim; Vernhettes, Samantha; Höfte, Herman; Lloyd, Clive

    2010-10-15

    Plant shoots have thick, polylamellate outer epidermal walls based on crossed layers of cellulose microfibrils, but the involvement of microtubules in such wall lamellation is unclear. Recently, using a long-term movie system in which Arabidopsis seedlings were grown in a biochamber, the tracks along which cortical microtubules move were shown to undergo slow rotary movements over the outer surface of hypocotyl epidermal cells. Because microtubules are known to guide cellulose synthases over the short term, we hypothesised that this previously unsuspected microtubule rotation could, over the longer term, help explain the cross-ply structure of the outer epidermal wall. Here, we test that hypothesis using Arabidopsis plants expressing the cellulose synthase GFP-CESA3 and show that cellulose synthase trajectories do rotate over several hours. Neither microtubule-stabilising taxol nor microtubule-depolymerising oryzalin affected the linear rate of GFP-CESA3 movement, but both stopped the rotation of cellulose synthase tracks. Transmission electron microscopy revealed that drug-induced suppression of rotation alters the lamellation pattern, resulting in a thick monotonous wall layer. We conclude that microtubule rotation, rather than any hypothetical mechanism for wall self-assembly, has an essential role in developing cross-ply wall texture.

  11. Spiral vane bioreactor

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Inventor)

    1991-01-01

    A spiral vane bioreactor of a perfusion type is described in which a vertical chamber, intended for use in a microgravity condition, has a central rotating filter assembly and has flexible membranes disposed to rotate annularly about the filter assembly. The flexible members have end portions disposed angularly with respect to one another. A fluid replenishment medium is input from a closed loop liquid system to a completely liquid filled chamber containing microcarrier beads, cells and a fluid medium. Output of spent medium is to the closed loop. In the closed loop, the output and input parameters are sensed by sensors. A manifold permits recharging of the nutrients and pH adjustment. Oxygen is supplied and carbon dioxide and bubbles are removed and the system is monitored and controlled by a microprocessor.

  12. Characterization and Application of a Disposable Rotating Bed Bioreactor for Mesenchymal Stem Cell Expansion.

    PubMed

    Neumann, Anne; Lavrentieva, Antonina; Heilkenbrinker, Alexandra; Loenne, Maren; Kasper, Cornelia

    2014-11-27

    Recruitment of mesenchymal stromal cells (MSC) into the field of tissue engineering is a promising development since these cells can be expanded vivo to clinically relevant numbers and, after expansion, retain their ability to differentiate into various cell lineages. Safety requirements and the necessity to obtain high cell numbers without frequent subcultivation of cells raised the question of the possibility of expanding MSC in one-way (single-use) disposable bioreactors. In this study, umbilical cord-derived MSC (UC-MSC) were expanded in a disposable Z 2000 H bioreactor under dynamic conditions. Z was characterized regarding residence time and mixing in order to evaluate the optimal bioreactor settings, enabling optimal mass transfer in the absence of shear stress, allowing an reproducible expansion of MSC, while maintaining their stemness properties. Culture of the UC-MSC in disposable Z 2000 H bioreactor resulted in a reproducible 8-fold increase of cell numbers after 5 days. Cells were shown to maintain specific MSC surface marker expression as well as trilineage differentiation potential and lack stress-induced premature senescence.

  13. Differentiation of cartilaginous anlagen in entire embryonic mouse limbs cultured in a rotating bioreactor

    NASA Astrophysics Data System (ADS)

    Montufar-Solis, D.; Oakley, C. R.; Jefferson, Y.; Duke, P. J.

    2003-10-01

    Mechanisms involved in development of the embryonic limb have remained the same throughout eons of genetic and environmental evolution under Earth gravity (lg). During the spaceflight era it has been of interest to explore the ancient theory that form of the skeleton develops in response to gravity, and that changes in gravitational forces can change the developmental pattern of the limb. This has been shown in vivo and in vitro, allowing the hypergravity of centrifugation and microgravity of space to be used as tools to increase our knowledge of limb development. In recapitulations of spaceflight experiments, premetatarsals were cultured in suspension in a bioreactor, and found to be shorter and less differentiated than those cultured in standard culture dishes. This study only measured length of the metatarsals, and did not account for possible changes due to the skeletal elements having a more in vivo 3D shape while in suspension vs. flattened tissues compressed by their own weight. A culture system with an outcome closer to in vivo and that supports growth of younger limb buds than traditional systems will allow studies of early Hox gene expression, and contribute to the understanding of very early stages of development. The purpose of the current experiment was to determine if entire limb buds could be cultured in the bioreactor, and to compare the growth and differentiation with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were cultured for six days, either in the bioreactor or in center-well organ culture dishes, fixed, and embedded for histology. E13 specimens grown in culture dishes were flat, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections showed excellent cartilage differentiation in both culture systems, with more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Younger limb buds fused together during culture, so an additional set of El 1

  14. Dr. Cheryl Nickerson studying Salmonella at Tulane University

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Dr. Cheryl Nickerson (right) of Tulane University is studying the effects of simulated low-g on a well-known pathogen, Salmonella typhimurium, a bacterium that causes two to four million cases of gastrointestinal illness in the United States each year. While most healthy people recover readily, S. typhimurium can kill people with weakened immune systems. Thus, a simple case of food poisoning could disrupt a space mission. Using the NASA rotating-wall bioreactor, Nickerson cultured S. typhimurium in modeled microgravity. Mice infected with the bacterium died an average of three days faster than the control mice, indicating that S. typhimurium's virulence was enhanced by the bioreactor. Earlier research showed that 3 percent of the genes were altered by exposure to the bioreactor. Nickerson's work earned her a 2001 Presidential Early Career Award for Scientists and Engineers.

  15. Biotechnology

    NASA Image and Video Library

    2003-01-22

    Dr. Cheryl Nickerson (right) of Tulane University is studying the effects of simulated low-g on a well-known pathogen, Salmonella typhimurium, a bacterium that causes two to four million cases of gastrointestinal illness in the United States each year. While most healthy people recover readily, S. typhimurium can kill people with weakened immune systems. Thus, a simple case of food poisoning could disrupt a space mission. Using the NASA rotating-wall bioreactor, Nickerson cultured S. typhimurium in modeled microgravity. Mice infected with the bacterium died an average of three days faster than the control mice, indicating that S. typhimurium's virulence was enhanced by the bioreactor. Earlier research showed that 3 percent of the genes were altered by exposure to the bioreactor. Nickerson's work earned her a 2001 Presidential Early Career Award for Scientists and Engineers.

  16. Simulated Microgravity Induces SOST/Sclerostin Upregulation in Osteocytes

    NASA Technical Reports Server (NTRS)

    Spatz, Jordan; Sibonga, Jean; Wu, Honglu; Barry, Kevin; Bouxsein, Mary; Pajevic, Paola Divieti

    2010-01-01

    Osteocytes are theorized to be the mechanosensors and transducers of mechanical forces in bone, yet the biological mechanism of this action remains elusive. Recent evidence suggests that SOST/Sclerostin is an important regulator of mechano-transduction. To investigate the molecular mechanisms of SOST/Sclerostin regulation under in-vitro and ex-vivo unloading we used the NASA Rotating Wall Vessel(RWV) Bioreactor. For in-vitro experiments, MLOY-4 osteocytic cells were seeded at a concentration of 250,000 cells onto 3D collagen scaffold (BD). Scaffolds (4 per condition) were either rotated in a vertical 50ml NASA/bioreactor vessel at 18 rpm (unloaded), cultured in a horizontal 50 ml NASA bioreactor vessel at 18 rpm (control for the sheared environment of vertical rotating vessel), or cultured in a static T-75 cm dish (static condition ) for 7days. For ex-vivo experiments, calvaria bones were harvested from 12-week old C57/Bl6 mice and sequentially digested with type I/II collagenase to remove periosteal osteoblasts. Calvaria halves (10 per condition) were then exposed to the same set of culture conditions described above. Simulated unloading, as achieved in the NASA RWV, resulted in enlarged, round osteocytes, as assessed by H&E staining, that was reminiscent of prior reports of unloading causing loss of osteocyte morphology and dendritic network connectivity. Semiquantitative realtime qPCR and immunohistochemistry from both in-vitro and ex-vivo RWV experiments demonstrated a four-fold up-regulation of SOST/Sclerostin. Furthermore, mRNA of the transcriptional SOST enhancer Mef2C was upregulated 1.4 fold in ex-vivo calvaria subjected to unloading conditions of the NASA RWV, suggesting that Mef2C might be an important regulator of mechano-sensation. These findings are consistent with results from seven day hindlimb unloading experiments, C57/B6 females, conducted in our laboratory and validate the use of the NASA RWV as a tool to study osteocyte mechanotransduction

  17. NASA's Bioreactor: Growing Cells in a Microgravity Environment. Educational Brief.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    This brief discusses growing cells in a microgravity environment for grades 9-12. Students are provided with plans for building a classroom bioreactor that can then be used with the included activity on seed growth in a microgravity environment. Additional experimental ideas are also suggested along with a history and background on microgravity…

  18. A novel perfused rotary bioreactor for cardiomyogenesis of embryonic stem cells.

    PubMed

    Teo, Ailing; Mantalaris, Athanasios; Song, Kedong; Lim, Mayasari

    2014-05-01

    Developments in bioprocessing technology play an important role for overcoming challenges in cardiac tissue engineering. To this end, our laboratory has developed a novel rotary perfused bioreactor for supporting three-dimensional cardiac tissue engineering. The dynamic culture environments provided by our novel perfused rotary bioreactor and/or the high-aspect rotating vessel produced constructs with higher viability and significantly higher cell numbers (up to 4 × 10(5) cells/bead) than static tissue culture flasks. Furthermore, cells in the perfused rotary bioreactor showed earlier gene expressions of cardiac troponin-T, α- and β-myosin heavy chains with higher percentages of cardiac troponin-I-positive cells and better uniformity of sacromeric α-actinin expression. A dynamic and perfused environment, as provided by this bioreactor, provides a superior culture performance in cardiac differentiation for embryonic stem cells particularly for larger 3D constructs.

  19. Wind tunnel wall interference investigations in NAE/NRC High Reynolds Number 2D Facility and NASA Langley 0.3m Transonic Cryogenic Tunnel

    NASA Technical Reports Server (NTRS)

    Chan, Y. Y.; Nishimura, Y.; Mineck, R. E.

    1989-01-01

    Results are reported from a NAE/NRC and NASA cooperative program on two-dimensional wind-tunnel wall-interference research, aimed at developing the technology for correcting or eliminating wall interference effects in two-dimensional transonic wind-tunnel investigations. Both NASA Langley and NAE facilities are described, along with a NASA-designed and fabricated airfoil model. It is shown that data from the NAE facility, corrected for wall interference, agree with those obtained from the NASA tunnel, which has adaptive walls; the comparison of surface pressure data shows that the flowfield conditions in which the model is investigated appear to be nearly identical under most conditions. It is concluded that both approaches, posttest correction and an adaptive wall, adequately eliminate the tunnel-wall interference effects.

  20. Mathematical modelling of cell layer growth in a hollow fibre bioreactor.

    PubMed

    Chapman, Lloyd A C; Whiteley, Jonathan P; Byrne, Helen M; Waters, Sarah L; Shipley, Rebecca J

    2017-04-07

    Generating autologous tissue grafts of a clinically useful volume requires efficient and controlled expansion of cell populations harvested from patients. Hollow fibre bioreactors show promise as cell expansion devices, owing to their potential for scale-up. However, further research is required to establish how to specify appropriate hollow fibre bioreactor operating conditions for expanding different cell types. In this study we develop a simple model for the growth of a cell layer seeded on the outer surface of a single fibre in a perfused hollow fibre bioreactor. Nutrient-rich culture medium is pumped through the fibre lumen and leaves the bioreactor via the lumen outlet or passes through the porous fibre walls and cell layer, and out via ports on the outer wall of the extra-capillary space. Stokes and Darcy equations for fluid flow in the fibre lumen, fibre wall, cell layer and extra-capillary space are coupled to reaction-advection-diffusion equations for oxygen and lactate transport through the bioreactor, and to a simple growth law for the evolution of the free boundary of the cell layer. Cells at the free boundary are assumed to proliferate at a rate that increases with the local oxygen concentration, and to die and detach from the layer if the local fluid shear stress or lactate concentration exceed critical thresholds. We use the model to predict operating conditions that maximise the cell layer growth for different cell types. In particular, we predict the optimal flow rate of culture medium into the fibre lumen and fluid pressure imposed at the lumen outlet for cell types with different oxygen demands and fluid shear stress tolerances, and compare the growth of the cell layer when the exit ports on the outside of the bioreactor are open with that when they are closed. Model simulations reveal that increasing the inlet flow rate and outlet fluid pressure increases oxygen delivery to the cell layer and, therefore, the growth rate of cells that are

  1. Spaceflight bioreactor studies of cells and tissues.

    PubMed

    Freed, Lisa E; Vunjak-Novakovic, Gordana

    2002-01-01

    well-being (loss of muscle and skeletal tissues [15-17]) and gene- and cell-level responses to the mechanical environment [13,14,18]. All five of the spaceflight bioreactor studies described above utilized three-dimensional cell culture systems in which the cells were associated with biodegradable polymer scaffolds [17], collagen gel [16], or microcarrier beads [13-15,18] in order to promote the expression of differentiated cell function. In four of the five spaceflight bioreactor studies [15-18], cells were cultured in perfused vessels (cartridges or rotating bioreactors) within recirculating loops designed to maintain medium composition within target ranges by a combination of gas exchange and fresh medium supply. Future spaceflight studies of cells and tissues are likely to involve a three-dimensional culture system, to promote cellular differentiation, and perfusion with or without rotation, to provide a gravity-independent mechanism for fluid mixing and mass transport. Previous spaceflight studies have guided the ongoing development of NASA flight hardware for the ISS (e.g. the EDU-2 and the CCU). This next generation of hardware will have extended operational capabilities including on-line microscopy, in-line sensors for the monitoring and control of metabolic parameters, modular design for replicate cultures, and, perhaps most importantly of all, compatibility with the ISS centrifuge. The latter will permit in-flight, 1 g control cultures, and thereby allow the experimental variable to be gravity itself rather than the more general "spaceflight environment". Technical limitations of spaceflight studies (e.g. allowable size, mass, and power) continue to motivate a creative approach to system design and to result in "spin-off" technologies (e.g. the STLV) for ground-based cell and tissue culture research. The increasing scientific and medical relevance of this work is evidenced by the growing number of publications in which advanced bioreactors are used for in

  2. Hydrofocusing Bioreactor Produces Anti-Cancer Alkaloids

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R.; Valluri, Jagan V.

    2011-01-01

    A methodology for growing three-dimensional plant tissue models in a hydrodynamic focusing bioreactor (HFB) has been developed. The methodology is expected to be widely applicable, both on Earth and in outer space, as a means of growing plant cells and aggregates thereof under controlled conditions for diverse purposes, including research on effects of gravitation and other environmental factors upon plant growth and utilization of plant tissue cultures to produce drugs in quantities greater and at costs lower than those of conventional methodologies. The HFB was described in Hydro focus - ing Bioreactor for Three-Dimensional Cell Culture (MSC-22358), NASA Tech Briefs, Vol. 27, No. 3 (March 2003), page 66. To recapitulate: The HFB offers a unique hydrofocusing capability that enables the creation of a low-shear liquid culture environment simultaneously with the herding of suspended cells and tissue assemblies and removal of unwanted air bubbles. The HFB includes a rotating cell-culture vessel with a centrally located sampling port and an internal rotating viscous spinner attached to a rotating base. The vessel and viscous spinner can be made to rotate at the same speed and direction or different speeds and directions to tailor the flow field and the associated hydrodynamic forces in the vessel in order to obtain low-shear suspension of cells and control of the locations of cells and air bubbles. For research and pharmaceutical-production applications, the HFB offers two major benefits: low shear stress, which promotes the assembly of cells into tissue-like three-dimensional constructs; and randomization of gravitational vectors relative to cells, which affects production of medicinal compounds. Presumably, apposition of plant cells in the absence of shear forces promotes cell-cell contacts, cell aggregation, and cell differentiation. Only gentle mixing is necessary for distributing nutrients and oxygen. It has been postulated that inasmuch as cells in the simulated

  3. Bioreactor Transient Exposure Activates Specific Neurotrophic Pathway in Cortical Neurons

    NASA Astrophysics Data System (ADS)

    Zimmitti, V.; Benedetti, E.; Caracciolo, V.; Sebastiani, P.; Di Loreto, S.

    2010-02-01

    Altered gravity forces might influence neuroplasticity and can provoke changes in biochemical mechanisms. In this contest, neurotrophins have a pivotal role, particularly nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF). A suspension of dissociated cortical cells from rat embryos was exposed to 24 h of microgravity before plating in normal adherent culture system. Expression and transductional signalling pathways of NGF and BDNF were assessed at the end of maturational process (8-10 days in vitro). Rotating wall vessel bioreactor (RWV) pre-exposition did not induce changes in NGF expression and its high affinity receptor TrkA. On the contrary both BDNF expression and its high affinity receptor TrkB were strongly up-regulated, inducing Erk-5, but not Erk-1/2 activation and, in turn, MEF2C over-expression and activation. According to our previous and present results, we postulate that relatively short microgravitational stimuli, applied to neural cells during the developmental stage, exert a long time activation of specific neurotrophic pathways.

  4. Alternating air-medium exposure in rotating bioreactors optimizes cell metabolism in 3D novel tubular scaffold polyurethane foams.

    PubMed

    Tresoldi, Claudia; Stefani, Ilaria; Ferracci, Gaia; Bertoldi, Serena; Pellegata, Alessandro F; Farè, Silvia; Mantero, Sara

    2017-04-26

    In vitro dynamic culture conditions play a pivotal role in developing engineered tissue grafts, where the supply of oxygen and nutrients, and waste removal must be permitted within construct thickness. For tubular scaffolds, mass transfer is enhanced by introducing a convective flow through rotating bioreactors with positive effects on cell proliferation, scaffold colonization and extracellular matrix deposition. We characterized a novel polyurethane-based tubular scaffold and investigated the impact of 3 different culture configurations over cell behavior: dynamic (i) single-phase (medium) rotation and (ii) double-phase exposure (medium-air) rotation; static (iii) single-phase static culture as control. A new mixture of polyol was tested to create polyurethane foams (PUFs) as 3D scaffold for tissue engineering. The structure obtained was morphologically and mechanically analyzed tested. Murine fibroblasts were externally seeded on the novel porous PUF scaffold, and cultured under different dynamic conditions. Viability assay, DNA quantification, SEM and histological analyses were performed at different time points. The PUF scaffold presented interesting mechanical properties and morphology adequate to promote cell adhesion, highlighting its potential for tissue engineering purposes. Results showed that constructs under dynamic conditions contain enhanced viability and cell number, exponentially increased for double-phase rotation; under this last configuration, cells uniformly covered both the external surface and the lumen. The developed 3D structure combined with the alternated exposure to air and medium provided the optimal in vitro biochemical conditioning with adequate nutrient supply for cells. The results highlight a valuable combination of material and dynamic culture for tissue engineering applications.

  5. Microgravity

    NASA Image and Video Library

    1998-10-10

    Isolation of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Isolate of long-term growth human mammary epithelial cells (HMEC) from outgrowth of duct element; cells shown soon after isolation and early in culture in a dish. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Tichmond, NASA/Marshall Space Flight Center (MSFC).

  6. Studies of Cell-Mediated Immunity Against Immune Disorders Using Synthetic Peptides and Rotating Bioreactor System

    NASA Technical Reports Server (NTRS)

    Sastry, Jagannadha K.

    1998-01-01

    We conducted a series of experiments using mouse immune-precursor cells, and observed that bioreactor culturing results in the loss of antigen-specific cytotoxic T lymphocyte (CTL) function. The reason for the abrogation of CTL function is microgravity conditions in the bioreactor, but not the antigen per se or its MHC restriction. Similarly, we observed that allostimulation of human PBMC in the bioreactor, but not in the T flask, resulted in the blunting of both allo-CTL function and the NK activity, indicating that the microgravity-associated functional defects are not unique to the mouse system. These results provide further confirmation to the microgravity-associated immune dysfunction, and constitute ground-based confirmatory data for those related to space-travel.

  7. Microgravity

    NASA Image and Video Library

    1998-10-10

    NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunourous tissues. Here, two High-Aspect Ratio Vessels turn at about 12 rmp to keep breast tissue constructs suspended inside the culture media. Syringes allow scientists to pull for analysis during growth sequences. The tube in the center is a water bubbler that dehumidifies the air to prevent evaporation of the media and thus the appearance of destructive bubbles in the bioreactor.

  8. Low-to-moderate Reynolds number swirling flow in an annular channel with a rotating end wall.

    PubMed

    Davoust, Laurent; Achard, Jean-Luc; Drazek, Laurent

    2015-02-01

    This paper presents a new method for solving analytically the axisymmetric swirling flow generated in a finite annular channel from a rotating end wall, with no-slip boundary conditions along stationary side walls and a slip condition along the free surface opposite the rotating floor. In this case, the end-driven swirling flow can be described from the coupling between an azimuthal shear flow and a two-dimensional meridional flow driven by the centrifugal force along the rotating floor. A regular asymptotic expansion based on a small but finite Reynolds number is used to calculate centrifugation-induced first-order correction to the azimuthal Stokes flow obtained as the solution at leading order. For solving the first-order problem, the use of an integral boundary condition for the vorticity is found to be a convenient way to attribute boundary conditions in excess for the stream function to the vorticity. The annular geometry is characterized by both vertical and horizontal aspect ratios, whose respective influences on flow patterns are investigated. The vertical aspect ratio is found to involve nontrivial changes in flow patterns essentially due to the role of corner eddies located on the left and right sides of the rotating floor. The present analytical method can be ultimately extended to cylindrical geometries, irrespective of the surface opposite the rotating floor: a wall or a free surface. It can also serve as an analytical tool for monitoring confined rotating flows in applications related to surface viscosimetry or crystal growth from the melt.

  9. Suspension cell culture in microgravity and development of a space bioreactor

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.

    1987-01-01

    NASA has methodically developed unique suspension type cell and recovery apparatus culture systems for bioprocess technology experiments and production of biological products in microgravity. The first space bioreactor has been designed for microprocessor control, no gaseous headspace, circulation and resupply of culture medium, and slow mixing in very low shear regimes. Various ground based bioreactors are being used to test reactor vessel design, on-line sensors, effects of shear, nutrient supply, and waste removal from continuous culture of human cells attached to microcarriers. The small (500 ml) bioreactor is being constructed for flight experiments in the Shuttle middeck to verify systems operation under microgravity conditions and to measure the efficiencies of mass transport, gas transfer, oxygen consumption, and control of low shear stress on cells.

  10. Microgravity-Enhanced Stem Cell Selection

    NASA Technical Reports Server (NTRS)

    Claudio, Pier Paolo; Valluri, Jagan

    2011-01-01

    conventional bioreactors, stirring invokes deleterious forces that disrupt cell aggregation and results in cell death. First-generation rotating bioreactors provided rotation on the horizontal axis, which resulted in the suspension of cells without stirring, thus providing a suitable environment to propagate cells without sedimentation to a surface. The rotating wall bioreactors did not provide a way to remove air bubbles that were causing shear and disrupting 3D cultures. Johnson Space Center successfully engineered the hydrofocusing bioreactor (HFB) that resolved the problem of removing the air bubbles from the fluid medium of NASA's rotating-wall space bioreactors. The HFB uses the principle of hydrodynamic focusing that simultaneously produces a low-shear fluid culture environment and a variable hydrofocusing force that can control the movement, location, and removal of suspended cells, tissues, and air bubbles from the bioreactor. The HFB is a rotating, domeshaped cell culture vessel with a centrally located sampling port and an internal viscous spinner. The vessel and spinner can rotate at different speeds either in the same or opposite directions. Rotation of the vessel and viscous interaction at the spinner generate a hydrofocusing force. Adjusting the differential rotation rate between vessel and spinner controls the magnitude of the force.

  11. 3D Printed Vascular Networks Enhance Viability in High-Volume Perfusion Bioreactor.

    PubMed

    Ball, Owen; Nguyen, Bao-Ngoc B; Placone, Jesse K; Fisher, John P

    2016-12-01

    There is a significant clinical need for engineered bone graft substitutes that can quickly, effectively, and safely repair large segmental bone defects. One emerging field of interest involves the growth of engineered bone tissue in vitro within bioreactors, the most promising of which are perfusion bioreactors. Using bioreactor systems, tissue engineered bone constructs can be fabricated in vitro. However, these engineered constructs lack inherent vasculature and once implanted, quickly develop a necrotic core, where no nutrient exchange occurs. Here, we utilized COMSOL modeling to predict oxygen diffusion gradients throughout aggregated alginate constructs, which allowed for the computer-aided design of printable vascular networks, compatible with any large tissue engineered construct cultured in a perfusion bioreactor. We investigated the effect of 3D printed macroscale vascular networks with various porosities on the viability of human mesenchymal stem cells in vitro, using both gas-permeable, and non-gas permeable bioreactor growth chamber walls. Through the use of 3D printed vascular structures in conjunction with a tubular perfusion system bioreactor, cell viability was found to increase by as much as 50% in the core of these constructs, with in silico modeling predicting construct viability at steady state.

  12. 3D Printed Vascular Networks Enhance Viability in High-Volume Perfusion Bioreactor

    PubMed Central

    Ball, Owen; Nguyen, Bao-Ngoc B.; Placone, Jesse K.; Fisher, John P.

    2016-01-01

    There is a significant clinical need for engineered bone graft substitutes that can quickly, effectively, and safely repair large segmental bone defects. One emerging field of interest involves the growth of engineered bone tissue in vitro within bioreactors, the most promising of which are perfusion bioreactors. Using bioreactor systems, tissue engineered bone constructs can be fabricated in vitro. However, these engineered constructs lack inherent vasculature and once implanted, quickly develop a necrotic core, where no nutrient exchange occurs. Here, we utilized COMSOL modeling to predict oxygen diffusion gradients throughout aggregated alginate constructs, which allowed for the computer-aided design of printable vascular networks, compatible with any large tissue engineered construct cultured in a perfusion bioreactor. We investigated the effect of 3D printed macroscale vascular networks with various porosities on the viability of human mesenchymal stem cells in vitro, using both gas-permeable, and non-gas permeable bioreactor growth chamber walls. Through the use of 3D printed vascular structures in conjunction with a tubular perfusion system bioreactor, cell viability was found to increase by as much as 50% in the core of these constructs, with in silico modeling predicting construct viability at steady state. PMID:27272210

  13. Enhanced biodegradation of methylhydrazine and hydrazine contaminated NASA wastewater in fixed-film bioreactor.

    PubMed

    Nwankwoala, A U; Egiebor, N O; Nyavor, K

    2001-01-01

    The aerobic biodegradation of National Aeronautics and Space Administration (NASA) wastewater that contains mixtures of highly concentrated methylhydrazine/hydrazine, citric acid and their reaction product was studied on a laboratory-scale fixed film trickle-bed reactor. The degrading organisms, Achromobacter sp., Rhodococcus B30 and Rhodococcus J10, were immobilized on coarse sand grains used as support-media in the columns. Under continuous flow operation, Rhodococcus sp. degraded the methylhydrazine content of the wastewater from a concentration of 10 to 2.5 mg/mL within 12 days and the hydrazine from approximately 0.8 to 0.1 mg/mL in 7 days. The Achromobacter sp. was equally efficient in degrading the organics present in the wastewater, reducing the concentration of the methylhydrazine from 10 to approximately 5 mg/mL within 12 days and that of the hydrazine from approximately 0.8 to 0.2 mg/mL in 7 days. The pseudo first-order rate constants of 0.137 day(-1) and 0.232 day(-1) were obtained for the removal of methylhydrazine and hydrazine, respectively, in wastewater in the reactor column. In the batch cultures, rate constants for the degradation were 0.046 and 0.079 day(-1) for methylhydrazine and hydrazine respectively. These results demonstrate that the continuous flow bioreactor afford greater degradation efficiencies than those obtained when the wastewater was incubated with the microbes in growth-limited batch experiments. They also show that wastewater containing hydrazine is more amenable to microbial degradation than one that is predominant in methylhydrazine, in spite of the longer lag period observed for hydrazine containing wastewater. The influence of substrate concentration and recycle rate on the degradation efficiency is reported. The major advantages of the trickle-bed reactor over the batch system include very high substrate volumetric rate of turnover, higher rates of degradation and tolerance of the 100% concentrated NASA wastewater. The

  14. Application of Pressure-Based Wall Correction Methods to Two NASA Langley Wind Tunnels

    NASA Technical Reports Server (NTRS)

    Iyer, V.; Everhart, J. L.

    2001-01-01

    This paper is a description and status report on the implementation and application of the WICS wall interference method to the National Transonic Facility (NTF) and the 14 x 22-ft subsonic wind tunnel at the NASA Langley Research Center. The method calculates free-air corrections to the measured parameters and aerodynamic coefficients for full span and semispan models when the tunnels are in the solid-wall configuration. From a data quality point of view, these corrections remove predictable bias errors in the measurement due to the presence of the tunnel walls. At the NTF, the method is operational in the off-line and on-line modes, with three tests already computed for wall corrections. At the 14 x 22-ft tunnel, initial implementation has been done based on a test on a full span wing. This facility is currently scheduled for an upgrade to its wall pressure measurement system. With the addition of new wall orifices and other instrumentation upgrades, a significant improvement in the wall correction accuracy is expected.

  15. Evaluation of a Multi-Parameter Sensor for Automated, Continuous Cell Culture Monitoring in Bioreactors

    NASA Technical Reports Server (NTRS)

    Pappas, D.; Jeevarajan, A.; Anderson, M. M.

    2004-01-01

    Compact and automated sensors are desired for assessing the health of cell cultures in biotechnology experiments in microgravity. Measurement of cell culture medium allows for the optirn.jzation of culture conditions on orbit to maximize cell growth and minimize unnecessary exchange of medium. While several discrete sensors exist to measure culture health, a multi-parameter sensor would simplify the experimental apparatus. One such sensor, the Paratrend 7, consists of three optical fibers for measuring pH, dissolved oxygen (p02), dissolved carbon dioxide (pC02) , and a thermocouple to measure temperature. The sensor bundle was designed for intra-arterial placement in clinical patients, and potentially can be used in NASA's Space Shuttle and International Space Station biotechnology program bioreactors. Methods: A Paratrend 7 sensor was placed at the outlet of a rotating-wall perfused vessel bioreactor system inoculated with BHK-21 (baby hamster kidney) cells. Cell culture medium (GTSF-2, composed of 40% minimum essential medium, 60% L-15 Leibovitz medium) was manually measured using a bench top blood gas analyzer (BGA, Ciba-Corning). Results: A Paratrend 7 sensor was used over a long-term (>120 day) cell culture experiment. The sensor was able to track changes in cell medium pH, p02, and pC02 due to the consumption of nutrients by the BHK-21. When compared to manually obtained BGA measurements, the sensor had good agreement for pH, p02, and pC02 with bias [and precision] of 0.02 [0.15], 1 mm Hg [18 mm Hg], and -4.0 mm Hg [8.0 mm Hg] respectively. The Paratrend oxygen sensor was recalibrated (offset) periodically due to drift. The bias for the raw (no offset or recalibration) oxygen measurements was 42 mm Hg [38 mm Hg]. The measured response (rise) time of the sensor was 20 +/- 4s for pH, 81 +/- 53s for pC02, 51 +/- 20s for p02. For long-term cell culture measurements, these response times are more than adequate. Based on these findings , the Paratrend sensor could

  16. Microgravity

    NASA Image and Video Library

    2001-05-15

    Lisa Freed and Gordana Vunjak-Novakovic, both of the Massachusetts Institute of Technology (MIT), have taken the first steps toward engineering heart muscle tissue that could one day be used to patch damaged human hearts. Cells isolated from very young animals are attached to a three-dimensional polymer scaffold, then placed in a NASA bioreactor. The cells do not divide, but after about a week start to cornect to form a functional piece of tissue. Functionally connected heart cells that are capable of transmitting electrical signals are the goal for Freed and Vunjak-Novakovic. Electrophysiological recordings of engineered tissue show spontaneous contractions at a rate of 70 beats per minute (a), and paced contractions at rates of 80, 150, and 200 beats per minute respectively (b, c, and d). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: NASA and MIT.

  17. The Hematopoietic Stem Cell Therapy for Exploration of Deep Space

    NASA Technical Reports Server (NTRS)

    Ohi, Seigo; Roach, Allana-Nicole; Fitzgerald, Wendy; Riley, Danny A.; Gonda, Steven R.

    2003-01-01

    It is hypothesized that the hematopoietic stem cell therapy (HSCT) might countermeasure various space-caused disorders so as to maintain astronauts' homeostasis. If this were achievable, the HSCT could promote human exploration of deep space. Using animal models of disorders (hindlimb suspension unloading system and beta-thalassemia), the HSCT was tested for muscle loss, immunodeficiency and space anemia. The results indicate feasibility of HSCT for these disorders. To facilitate the HSCT in space, growth of HSCs were optimized in the NASA Rotating Wall Vessel (RWV) culture systems, including Hydrodynamic Focusing Bioreactor (HFB).

  18. Microgravity

    NASA Image and Video Library

    2000-12-15

    Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Even in normal gravity, bioactive glass particles enhance bone growth in laboratory tests with flat tissue cultures. Ducheyne and his team believe that using the bioactive microcarriers in a rotating bioreactor in microgravity will produce improved, three-dimensional tissue cultures. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and University of Pennsylvania Center for Bioactive Materials and Tissue Engineering.

  19. Bare Bones of Bioactive Glass

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Even in normal gravity, bioactive glass particles enhance bone growth in laboratory tests with flat tissue cultures. Ducheyne and his team believe that using the bioactive microcarriers in a rotating bioreactor in microgravity will produce improved, three-dimensional tissue cultures. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and University of Pennsylvania Center for Bioactive Materials and Tissue Engineering.

  20. Wall Boundary Layer Measurements for the NASA Langley Transonic Dynamics Tunnel

    NASA Technical Reports Server (NTRS)

    Wieseman, Carol D.; Bennett, Robert M.

    2007-01-01

    Measurements of the boundary layer parameters in the NASA Langley Transonic Dynamics tunnel were conducted during extensive calibration activities following the facility conversion from a Freon-12 heavy-gas test medium to R-134a. Boundary-layer rakes were mounted on the wind-tunnel walls, ceiling, and floor. Measurements were made over the range of tunnel operation envelope in both heavy gas and air and without a model in the test section at three tunnel stations. Configuration variables included open and closed east sidewall wall slots, for air and R134a test media, reentry flap settings, and stagnation pressures over the full range of tunnel operation. The boundary layer thickness varied considerably for the six rakes. The thickness for the east wall was considerably larger that the other rakes and was also larger than previously reported. There generally was some reduction in thickness at supersonic Mach numbers, but the effect of stagnation pressure, and test medium were not extensive.

  1. Influence of rotating in-plane field on vertical Bloch lines in the walls of second kind of dumbbell domains

    NASA Astrophysics Data System (ADS)

    Sun, H. Y.; Hu, H. N.; Sun, Y. P.; Nie, X. F.

    2004-08-01

    Influence of rotating in-plane field on vertical Bloch lines in the walls of second kind of dumbbell domains (IIDs) was investigated, and a critical in-plane field range [ Hip1, Hip2] of which vertical-Bloch lines (VBLs) annihilated in IIDs is found under rotating in-plane field ( Hip1 is the maximal critical in-plane-field of which hard domains remain stable, Hip2 is the minimal critical in-plane-field of which all of the hard domains convert to soft bubbles (SBs, without VBLs)). It shows that the in-plane field range [ Hip1, Hip2] changes with the change of the rotating angle Δ ϕ. Hip1 maintains stable, while Hip2 decreases with the decreasing of rotating angle Δ ϕ. Comparing it with the spontaneous shrinking experiment of IIDs under both bias field and in-plane field, we presume that under the application of in-plane field there exists a direction along which the VBLs in the domain walls annihilate most easily, and it is in the direction that domain walls are perpendicular to the in-plane field.

  2. Microgravity

    NASA Image and Video Library

    1998-10-10

    Isolation of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Outgrowth of cells from duct element in upper right corner cultured in a standard dish; most cells spontaneously die during early cell divisions, but a few will establish long-term growth. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Tichmond, NASA/Marshall Space Flight Center (MSFC).

  3. Microgravity

    NASA Image and Video Library

    1998-01-01

    Astronaut John Blaha replaces an exhausted media bag and filled waste bag with fresh bags to continue a bioreactor experiment aboard space station Mir in 1996. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. This image is from a video downlink. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  4. Human Peripheral Blood Mononuclear Cells Cultured in Normal and Hyperglycemic Media in Simulated Microgravity Using NASA Bioreactors

    NASA Technical Reports Server (NTRS)

    Lawless, DeSales

    2003-01-01

    We sought answers to several questions this summer at NASA Johnson Space Center. Initial studies involved the in vitro culture of human peripheral blood mononuclear in cells in different conditioned culture media. Several human cancer clones were similarly studied to determine responses to aberrant glycosylation by the argon laser. The cells were grown at unit gravity in flasks and in simulated microgravity using NASA bioreactors. The cells in each instance were analyzed by flow cytometry. Cell cycle analysis was acquired by staining nuclear DNA with propidium iodide. Responses to the laser stimulation was measured by observing autofluorescence emitted in the green and red spectra after stimulation. Extent of glycosylation correlated with the intensity of the laser stimulated auto-fluorescence. Our particular study was to detect and monitor aberrant glycosylation and its role in etiopathogenesis. Comparisons were made between cells known to be neoplastic and normal cell controls using the same Laser Induced Autofluorescence technique. Studies were begun after extensive literature searches on using the antigen presenting potential of dendritic cells to induce proliferation of antigen specific cytotoxic T-cells. The Sendai virus served as the antigen. Our goal is to generate sufficient numbers of such cells in the simulated microgravity environment for use in autologous transplants of virally infected individuals including those positive for hepatitis and HIV.

  5. Rotating wall vessel exposure alters protein secretion and global gene expression in Staphylococcus aureus

    NASA Astrophysics Data System (ADS)

    Rosado, Helena; O'Neill, Alex J.; Blake, Katy L.; Walther, Meik; Long, Paul F.; Hinds, Jason; Taylor, Peter W.

    2012-04-01

    Staphylococcus aureus is routinely recovered from air and surface samples taken aboard the International Space Station (ISS) and poses a health threat to crew. As bacteria respond to the low shear forces engendered by continuous rotation conditions in a Rotating Wall Vessel (RWV) and the reduced gravitational field of near-Earth flight by altering gene expression, we examined the effect of low-shear RWV growth on protein secretion and gene expression by three S. aureus isolates. When cultured under 1 g, the total amount of protein secreted by these strains varied up to fourfold; under continuous rotation conditions, protein secretion by all three strains was significantly reduced. Concentrations of individual proteins were differentially reduced and no evidence was found for increased lysis. These data suggest that growth under continuous rotation conditions reduces synthesis or secretion of proteins. A limited number of changes in gene expression under continuous rotation conditions were noted: in all isolates vraX, a gene encoding a polypeptide associated with cell wall stress, was down-regulated. A vraX deletion mutant of S. aureus SH1000 was constructed: no differences were found between SH1000 and ΔvraX with respect to colony phenotype, viability, protein export, antibiotic susceptibility, vancomycin kill kinetics, susceptibility to cold or heat and gene modulation. An ab initio protein-ligand docking simulation suggests a major binding site for β-lactam drugs such as imipenem. If such changes to the bacterial phenotype occur during spaceflight, they will compromise the capacity of staphylococci to cause systemic infection and to circumvent antibacterial chemotherapy.

  6. Method for culturing mammalian cells in a perfused bioreactor

    NASA Technical Reports Server (NTRS)

    Schwarz, Ray P. (Inventor); Wolf, David A. (Inventor)

    1992-01-01

    A bio-reactor system wherein a tubular housing contains an internal circularly disposed set of blade members and a central tubular filter all mounted for rotation about a common horizontal axis and each having independent rotational support and rotational drive mechanisms. The housing, blade members and filter preferably are driven at a constant slow speed for placing a fluid culture medium with discrete microbeads and cell cultures in a discrete spatial suspension in the housing. Replacement fluid medium is symmetrically input and fluid medium is symmetrically output from the housing where the input and the output are part of a loop providing a constant or intermittent flow of fluid medium in a closed loop.

  7. Effects of rotation on coolant passage heat transfer. Volume 1: Coolant passages with smooth walls

    NASA Technical Reports Server (NTRS)

    Hajek, T. J.; Wagner, J. H.; Johnson, B. V.; Higgins, A. W.; Steuber, G. D.

    1991-01-01

    An experimental program was conducted to investigate heat transfer and pressure loss characteristics of rotating multipass passages, for configurations and dimensions typical of modern turbine blades. The immediate objective was the generation of a data base of heat transfer and pressure loss data required to develop heat transfer correlations and to assess computational fluid dynamic techniques for rotating coolant passages. Experiments were conducted in a smooth wall large scale heat transfer model.

  8. Studies of Cell-Mediated Immunity Against Immune Disorders Using Synthetic Peptides and Rotating Bioreactor System

    NASA Technical Reports Server (NTRS)

    Sastry, Jagannadha K.

    1997-01-01

    Our proposed experiments included: (1) immunzing mice with synthetic peptides; (2) preparing spleen and lymph node cells; (3) growing them under conventional conditions as well as in the rotatory vessel in appropriate medium reconstituting with synthetic peptides and/or cytokines as needed; and (4) comparing at regular time intervals the specific CTL activity as well as helper T-cell activity (in terms of both proliferative responses and cytokine production) using established procedures in my laboratory. We further proposed that once we demonstrated the merit of rotatory vessel technology to achieve desired results, these studies would be expanded to include immune cells from non-human primates (rhesus monkeys and chimpanzees) and also humans. We conducted a number of experiments to determine CTL induction by the synthetic peptides corresponding to antigenic proteins in HIV and HPV in different mouse strains that express MHC haplotypes H-2b or H-2d. We immunized mice with 100 ug of the synthetic peptide, suspended in sterile water, and emulsified in CFA (1:1). The immune lymph node cells obtained after 7 days were restimulated by culturing in T25 flask, HARV-10, or STLV-50, in the presence of the peptide at 20 ug/ml. The results from the 5'Cr-release assay consistently revealed complete abrogation of CTL activity of cells grown in the bioreactors (both HARV and STLV), while significant antigen-specific CTL activity was observed with cells cultured in tissue culture flasks. Thus, overall the data we generated in this study proved the usefulness of the NASA-developed developed technology for understanding the known immune deficiency during space travel. Additionally, this ex vivo microgravity technology since it mimics effectively the in vivo situation, it is also useful in understanding immune disorders in general. Thus, our proposed studies in TMC-NASA contract round II application benefit from data generated in this TMC-NASA contract round I study.

  9. Microgravity

    NASA Image and Video Library

    2001-05-15

    Lisa Freed and Gordana Vunjak-Novakovic, both of the Massachusetts Institute of Technology (MIT), have taken the first steps toward engineering heart muscle tissue that could one day be used to patch damaged human hearts. Cells isolated from very young animals are attached to a three-dimensional polymer scaffold, then placed in a NASA bioreactor. The cells do not divide, but after about a week start to cornect to form a functional piece of tissue. Here, a transmission electron micrograph of engineered tissue shows a number of important landmarks present in functional heart tissue: (A) well-organized myofilaments (Mfl), z-lines (Z), and abundant glycogen granules (Gly); and (D) intercalcated disc (ID) and desmosomes (DES). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: MIT

  10. Sensing in tissue bioreactors

    NASA Astrophysics Data System (ADS)

    Rolfe, P.

    2006-03-01

    Specialized sensing and measurement instruments are under development to aid the controlled culture of cells in bioreactors for the fabrication of biological tissues. Precisely defined physical and chemical conditions are needed for the correct culture of the many cell-tissue types now being studied, including chondrocytes (cartilage), vascular endothelial cells and smooth muscle cells (blood vessels), fibroblasts, hepatocytes (liver) and receptor neurones. Cell and tissue culture processes are dynamic and therefore, optimal control requires monitoring of the key process variables. Chemical and physical sensing is approached in this paper with the aim of enabling automatic optimal control, based on classical cell growth models, to be achieved. Non-invasive sensing is performed via the bioreactor wall, invasive sensing with probes placed inside the cell culture chamber and indirect monitoring using analysis within a shunt or a sampling chamber. Electroanalytical and photonics-based systems are described. Chemical sensing for gases, ions, metabolites, certain hormones and proteins, is under development. Spectroscopic analysis of the culture medium is used for measurement of glucose and for proteins that are markers of cell biosynthetic behaviour. Optical interrogation of cells and tissues is also investigated for structural analysis based on scatter.

  11. Microgravity

    NASA Image and Video Library

    1996-06-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues currently being cultured in rotating bioreactors by investigators

  12. Microgravity

    NASA Image and Video Library

    1988-07-14

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues currently being cultured in rotating bioreactors by investigators.

  13. Saccharomyces cerevisiae gene expression changes during rotating wall vessel suspension culture

    NASA Technical Reports Server (NTRS)

    Johanson, Kelly; Allen, Patricia L.; Lewis, Fawn; Cubano, Luis A.; Hyman, Linda E.; Hammond, Timothy G.

    2002-01-01

    This study utilizes Saccharomyces cerevisiae to study genetic responses to suspension culture. The suspension culture system used in this study is the high-aspect-ratio vessel, one type of the rotating wall vessel, that provides a high rate of gas exchange necessary for rapidly dividing cells. Cells were grown in the high-aspect-ratio vessel, and DNA microarray and metabolic analyses were used to determine the resulting changes in yeast gene expression. A significant number of genes were found to be up- or downregulated by at least twofold as a result of rotational growth. By using Gibbs promoter alignment, clusters of genes were examined for promoter elements mediating these genetic changes. Candidate binding motifs similar to the Rap1p binding site and the stress-responsive element were identified in the promoter regions of differentially regulated genes. This study shows that, as in higher order organisms, S. cerevisiae changes gene expression in response to rotational culture and also provides clues for investigations into the signaling pathways involved in gravitational response.

  14. Magnetoexcitons and Faraday rotation in single-walled carbon nanotubes and graphene nanoribbons

    NASA Astrophysics Data System (ADS)

    Have, Jonas; Pedersen, Thomas G.

    2018-03-01

    The magneto-optical response of single-walled carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) is studied theoretically, including excitonic effects. Both diagonal and nondiagonal response functions are obtained and employed to compute Faraday rotation spectra. For single-walled CNTs in a parallel field, the results show field-dependent splitting of the exciton absorption peaks caused by brightening a dark exciton state. Similarly, for GNRs in a perpendicular magnetic field, we observe a field-dependent shift of the exciton peaks and the emergence of an absorption peak above the energy gap. Results show that excitonic effects play a significant role in the optical response of both materials, particularly for the off-diagonal tensor elements.

  15. Microgravity

    NASA Image and Video Library

    1998-10-10

    Epithelial and fibroblast cell coculture: Long-term growth human mammary epithelial cells (HMEC) admixed in coculture with fibroblast from the same initial breast tissue grown as 3-dimenstional constructions in the presence of attachment beads in the NASA Bioreactor. A: A typical constrct about 2.0 mm in diameter without beads on the surface. The center of these constrcts is hollow, and beads are organized about the irner surface. Although the coculture provides smaller constructs than the monoculture, the metabolic of the organized cells is about the same. B, C, D: Closer views of cells showing that the shape of cells and cell-to-cell interactions apprear different in the coculture than in the monoculture constructs. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Richmond, NASA/Marshall Space Flight Center (MSFC).

  16. Microgravity

    NASA Image and Video Library

    2001-06-01

    The schematic depicts the major elements and flow patterns inside the NASA Bioreactor system. Waste and fresh medium are contained in plastic bags placed side-by-side so the waste bag fills as the fresh medium bag is depleted. The compliance vessel contains a bladder to accommodate pressure transients that might damage the system. A peristolic pump moves fluid by squeezing the plastic tubing, thus avoiding potential contamination. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  17. A Novel Bioreactor System for the Assessment of Endothelialization on Deformable Surfaces

    PubMed Central

    Bachmann, Björn J.; Bernardi, Laura; Loosli, Christian; Marschewski, Julian; Perrini, Michela; Ehrbar, Martin; Ermanni, Paolo; Poulikakos, Dimos; Ferrari, Aldo; Mazza, Edoardo

    2016-01-01

    The generation of a living protective layer at the luminal surface of cardiovascular devices, composed of an autologous functional endothelium, represents the ideal solution to life-threatening, implant-related complications in cardiovascular patients. The initial evaluation of engineering strategies fostering endothelial cell adhesion and proliferation as well as the long-term tissue homeostasis requires in vitro testing in environmental model systems able to recapitulate the hemodynamic conditions experienced at the blood-to-device interface of implants as well as the substrate deformation. Here, we introduce the design and validation of a novel bioreactor system which enables the long-term conditioning of human endothelial cells interacting with artificial materials under dynamic combinations of flow-generated wall shear stress and wall deformation. The wall shear stress and wall deformation values obtained encompass both the physiological and supraphysiological range. They are determined through separate actuation systems which are controlled based on validated computational models. In addition, we demonstrate the good optical conductivity of the system permitting online monitoring of cell activities through live-cell imaging as well as standard biochemical post-processing. Altogether, the bioreactor system defines an unprecedented testing hub for potential strategies toward the endothelialization or re-endothelialization of target substrates. PMID:27941901

  18. Wall-Resolved Large-Eddy Simulation of Flow Separation Over NASA Wall-Mounted Hump

    NASA Technical Reports Server (NTRS)

    Uzun, Ali; Malik, Mujeeb R.

    2017-01-01

    This paper reports the findings from a study that applies wall-resolved large-eddy simulation to investigate flow separation over the NASA wall-mounted hump geometry. Despite its conceptually simple flow configuration, this benchmark problem has proven to be a challenging test case for various turbulence simulation methods that have attempted to predict flow separation arising from the adverse pressure gradient on the aft region of the hump. The momentum-thickness Reynolds number of the incoming boundary layer has a value that is near the upper limit achieved by recent direct numerical simulation and large-eddy simulation of incompressible turbulent boundary layers. The high Reynolds number of the problem necessitates a significant number of grid points for wall-resolved calculations. The present simulations show a significant improvement in the separation-bubble length prediction compared to Reynolds-Averaged Navier-Stokes calculations. The current simulations also provide good overall prediction of the skin-friction distribution, including the relaminarization observed over the front portion of the hump due to the strong favorable pressure gradient. We discuss a number of problems that were encountered during the course of this work and present possible solutions. A systematic study regarding the effect of domain span, subgrid-scale model, tunnel back pressure, upstream boundary layer conditions and grid refinement is performed. The predicted separation-bubble length is found to be sensitive to the span of the domain. Despite the large number of grid points used in the simulations, some differences between the predictions and experimental observations still exist (particularly for Reynolds stresses) in the case of the wide-span simulation, suggesting that additional grid resolution may be required.

  19. Controlled-Turbulence Bioreactors

    NASA Technical Reports Server (NTRS)

    Wolf, David A.; Schwartz, Ray; Trinh, Tinh

    1989-01-01

    Two versions of bioreactor vessel provide steady supplies of oxygen and nutrients with little turbulence. Suspends cells in environment needed for sustenance and growth, while inflicting less damage from agitation and bubbling than do propeller-stirred reactors. Gentle environments in new reactors well suited to delicate mammalian cells. One reactor kept human kidney cells alive for as long as 11 days. Cells grow on carrier beads suspended in liquid culture medium that fills cylindrical housing. Rotating vanes - inside vessel but outside filter - gently circulates nutrient medium. Vessel stationary; magnetic clutch drives filter cylinder and vanes. Another reactor creates even less turbulence. Oxygen-permeable tubing wrapped around rod extending along central axis. Small external pump feeds oxygen to tubing through rotary coupling, and oxygen diffuses into liquid medium.

  20. Design and Use of a Novel Bioreactor for Regeneration of Biaxially Stretched Tissue-Engineered Vessels

    PubMed Central

    Huang, Angela Hai; Lee, Yong-Ung; Calle, Elizabeth A.; Boyle, Michael; Starcher, Barry C.; Humphrey, Jay D.

    2015-01-01

    Conventional bioreactors are used to enhance extracellular matrix (ECM) production and mechanical strength of tissue-engineered vessels (TEVs) by applying circumferential strain, which is uniaxial stretching. However, the resulting TEVs still suffer from inadequate mechanical properties, where rupture strengths and compliance values are still very different from native arteries. The biomechanical milieu of native arteries consists of both circumferential and axial loading. Therefore, to better simulate the physiological stresses acting on native arteries, we built a novel bioreactor system to enable biaxial stretching of engineered arteries during culture. This new bioreactor system allows for independent control of circumferential and axial stretching parameters, such as displacement and beat rate. The assembly and setup processes for this biaxial bioreactor system are reliable with a success rate greater than 75% for completion of long-term sterile culture. This bioreactor also supports side-by-side assessments of TEVs that are cultured under three types of mechanical conditions (static, uniaxial, and biaxial), all within the same biochemical environment. Using this bioreactor, we examined the impact of biaxial stretching on arterial wall remodeling of TEVs. Biaxial TEVs developed the greatest wall thickness compared with static and uniaxial TEVs. Unlike uniaxial loading, biaxial loading led to undulated collagen fibers that are commonly found in native arteries. More importantly, the biaxial TEVs developed the most mature elastin in the ECM, both qualitatively and quantitatively. The presence of mature extracellular elastin along with the undulated collagen fibers may contribute to the observed vascular compliance in the biaxial TEVs. The current work shows that biaxial stretching is a novel and promising means to improve TEV generation. Furthermore, this novel system allows us to optimize biomechanical conditioning by unraveling the interrelationships among the

  1. Studies of chondrogenesis in rotating systems

    NASA Technical Reports Server (NTRS)

    Duke, P. J.; Daane, E. L.; Montufar-Solis, D.

    1993-01-01

    A great deal of energy has been exerted over the years researching methods for regenerating and repairing bone and cartilage. Several techniques, especially bone implants and grafts, show great promise for providing a remedy for many skeletal disorders and chondrodystrophies. The bioreactor (rotating-wall vessel, RWV) is a cell culture system that creates a nurturing environment conducive to cell aggregation. Chondrocyte cultures have been studied as implants for repair and replacement of damaged and missing bone and cartilage since 1965 [Chesterman and Smith, J Bone Joint Surg 50B:184-197, 1965]. The ability to use large, tissue-like cartilage aggregates grown in the RWV would be of great clinical significance in treating skeletal disorders. In addition, the RWV may provide a superior method for studying chondrogenesis and chondrogenic mutations. Because the RWV is also reported to simulate many of the conditions of microgravity it is a very useful ground-based tool for studying how cell systems will react to microgravity.

  2. Bioreactor-based bone tissue engineering: The influence of dynamic flow on osteoblast phenotypic expression and matrix mineralization

    PubMed Central

    Yu, Xiaojun; Botchwey, Edward A.; Levine, Elliot M.; Pollack, Solomon R.; Laurencin, Cato T.

    2004-01-01

    An important issue in tissue engineering concerns the possibility of limited tissue ingrowth in tissue-engineered constructs because of insufficient nutrient transport. We report a dynamic flow culture system using high-aspect-ratio vessel rotating bioreactors and 3D scaffolds for culturing rat calvarial osteoblast cells. 3D scaffolds were designed by mixing lighter-than-water (density, <1g/ml) and heavier-than-water (density, >1g/ml) microspheres of 85:15 poly(lactide-co-glycolide). We quantified the rate of 3D flow through the scaffolds by using a particle-tracking system, and the results suggest that motion trajectories and, therefore, the flow velocity around and through scaffolds in rotating bioreactors can be manipulated by varying the ratio of heavier-than-water to lighter-than-water microspheres. When rat primary calvarial cells were cultured on the scaffolds in bioreactors for 7 days, the 3D dynamic flow environment affected bone cell distribution and enhanced cell phenotypic expression and mineralized matrix synthesis within tissue-engineered constructs compared with static conditions. These studies provide a foundation for exploring the effects of dynamic flow on osteoblast function and provide important insight into the design and optimization of 3D scaffolds suitable in bioreactors for in vitro tissue engineering of bone. PMID:15277663

  3. Microgravity

    NASA Image and Video Library

    1998-10-10

    Isolation of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue. Same long-term growth human mammary epithelial cells (HMEC), but after 3 weeks in concinuous culture. Note attempts to reform duct elements, but this time in two dimensions in a dish rather that in three demensions in tissue. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Tichmond, NASA/Marshall Space Flight Center (MSFC).

  4. Bioreactor Scalability: Laboratory-Scale Bioreactor Design Influences Performance, Ecology, and Community Physiology in Expanded Granular Sludge Bed Bioreactors

    PubMed Central

    Connelly, Stephanie; Shin, Seung G.; Dillon, Robert J.; Ijaz, Umer Z.; Quince, Christopher; Sloan, William T.; Collins, Gavin

    2017-01-01

    Studies investigating the feasibility of new, or improved, biotechnologies, such as wastewater treatment digesters, inevitably start with laboratory-scale trials. However, it is rarely determined whether laboratory-scale results reflect full-scale performance or microbial ecology. The Expanded Granular Sludge Bed (EGSB) bioreactor, which is a high-rate anaerobic digester configuration, was used as a model to address that knowledge gap in this study. Two laboratory-scale idealizations of the EGSB—a one-dimensional and a three- dimensional scale-down of a full-scale design—were built and operated in triplicate under near-identical conditions to a full-scale EGSB. The laboratory-scale bioreactors were seeded using biomass obtained from the full-scale bioreactor, and, spent water from the distillation of whisky from maize was applied as substrate at both scales. Over 70 days, bioreactor performance, microbial ecology, and microbial community physiology were monitored at various depths in the sludge-beds using 16S rRNA gene sequencing (V4 region), specific methanogenic activity (SMA) assays, and a range of physical and chemical monitoring methods. SMA assays indicated dominance of the hydrogenotrophic pathway at full-scale whilst a more balanced activity profile developed during the laboratory-scale trials. At each scale, Methanobacterium was the dominant methanogenic genus present. Bioreactor performance overall was better at laboratory-scale than full-scale. We observed that bioreactor design at laboratory-scale significantly influenced spatial distribution of microbial community physiology and taxonomy in the bioreactor sludge-bed, with 1-D bioreactor types promoting stratification of each. In the 1-D laboratory bioreactors, increased abundance of Firmicutes was associated with both granule position in the sludge bed and increased activity against acetate and ethanol as substrates. We further observed that stratification in the sludge-bed in 1-D laboratory

  5. Utilization of Microgravity Bioreactor for Differentiation and Growth of Human Vascular Endothelial Cells

    NASA Technical Reports Server (NTRS)

    Chen, Chu-Huang; Pellis, Neal R.

    1997-01-01

    The goal was to delineate mechanisms of genetic responses to angiogenic stimulation of human coronary arterial and dermal microvascular endothelial cells during exposure to microgravity. The NASA-designed rotating-wall vessel was used to create a three-dimensional culture environment with low shear-stress and microgravity simulating that in space. The primary specific aim was to determine whether simulated microgravity enhances endothelial cell growth and whether the growth enhancement is associated by augmented expression of Basic Fibroblast Growth Factor (BFGF) and c-fos, an immediate early gene and component of the transcription factor AP-1.

  6. Effects of Simulated Microgravity on Otolith Growth of Larval Zebrafish using a Rotating-Wall Vessel: Appropriate Rotation Speed and Fish Developmental Stage

    NASA Astrophysics Data System (ADS)

    Li, Xiaoyan; Anken, Ralf; Liu, Liyue; Wang, Gaohong; Liu, Yongding

    2017-02-01

    Stimulus dependence is a general feature of developing animal sensory systems. In this respect, it has extensively been shown earlier that fish inner ear otoliths can act as test masses as their growth is strongly affected by altered gravity such as hypergravity obtained using centrifuges, by (real) microgravity achieved during spaceflight or by simulated microgravity using a ground-based facility. Since flight opportunities are scarce, ground-based simulators of microgravity, using a wide variety of physical principles, have been developed to overcome this shortcoming. Not all of them, however, are equally well suited to provide functional weightlessness from the perspective of the biosystem under evaluation. Therefore, the range of applicability of a particular simulator has to be extensively tested. Earlier, we have shown that a Rotating-Wall Vessel (RWV) can be used to provide simulated microgravity for developing Zebrafish regarding the effect of rotation on otolith development. In the present study, we wanted to find the most effective speed of rotation and identify the appropriate developmental stage of Zebrafish, where effects are the largest, in order to provide a methodological basis for future in-depth analyses dedicated to the physiological processes underlying otolith growth at altered gravity. Last not least, we compared data on the effect of simulated microgravity on the size versus the weight of otoliths, since the size usually is measured in related studies due to convenience, but the weight more accurately approximates the physical capacity of an otolith. Maintaining embryos at 10 hours post fertilization for three days in the RWV, we found that 15 revolutions per minute (rpm) yielded the strongest effects on otolith growth. Maintenance of Zebrafish staged at 10 hpf, 1 day post fertilization (dpf), 4 dpf, 7 dpf and 14 dpf for three days at 15 rpm resulted in the most prominent effects in 7 dpf larvae. Weighing versus measuring the size of otoliths

  7. Characterizing the plasma of the Rotating Wall Machine

    NASA Astrophysics Data System (ADS)

    Hannum, David A.

    The Rotating Wall Machine (RoWM) is a line-tied linear screw pinch built to study current-driven external kink modes. The plasma column is formed by an array of seven electrostatic washer guns which can also be biased to drive plasma current. The array allows independent control over the electron density ne and current density Jz profiles of the column. Internal measurements of the plasma have been made with singletip Langmuir and magnetic induction ("B-dot") probes for a range of bias currents (Ib = 0, 300, 500 A/gun). Streams from the individual guns are seen to merge at a distance of z ≈ 36 cm from the guns; the exact distance depends on the value of Ib. The density of the column is directly proportional to the Ohmic dissipation power, but the temperature stays at a low, uniform value (Te ≈ 3.5 eV) for each bias level. Electron densities are on the order of ne ˜10 20 m-3. The electron density expands radially (across the Bz guide field) as the plasma moves along the column, though the current density Jz mainly stays parallel to the field lines. The singletip Langmuir probe diagnostic is difficult to analyze for Ib = 500 A/gun plasmas and fails as Ib is raised beyond this level. Spectrographic analysis of the Halpha line indicates that the hydrogen plasmas are nearly fully ionized at each bias level. Azimuthal E x B rotation is axially and radially sheared; rotation slows as the plasma reaches the anode. Perpendicular diffusivity is consistent with the classical value, D⊥ ≈ 5 m2/sec, while parallel resistivity is seen to be twice the classical Spitzer value, 2 x 10-4 O m.

  8. NASA Thesaurus. Volumes 1 and 2; Hierarchical Listing with Definitions; Rotated Term Display

    NASA Technical Reports Server (NTRS)

    2012-01-01

    The NASA Thesaurus contains the authorized subject terms by which the documents in the NASA STI Databases are indexed and retrieved. The scope of this controlled vocabulary includes not only aerospace engineering, but all supporting areas of engineering and physics, the natural space sciences (astronomy, astrophysics, planetary science), Earth sciences, and to some extent, the biological sciences. Volume 1 - Hierarchical Listing With Definitions contains over 18,400 subject terms, 4,300 definitions, and more than 4,500 USE cross references. The Hierarchical Listing presents full hierarchical structure for each term along with 'related term' lists, and can serve as an orthographic authority. Volume 2 - Rotated Term Display is a ready-reference tool which provides over 52,700 additional 'access points' to the thesaurus terminology. It contains the postable and nonpostable terms found in the Hierarchical Listing arranged in a KWIC (key-word-in-context) index. This CD-ROM version of the NASA Thesaurus is in PDF format and is updated to the current year of purchase.

  9. A Rotating Bioreactor for Scalable Culture and Differentiation of Respiratory Epithelium

    PubMed Central

    Raredon, Micha Sam Brickman; Ghaedi, Mahboobe; Calle, Elizabeth A.; Niklason, Laura E.

    2015-01-01

    Respiratory epithelium is difficult to grow in vitro, as it requires a well-maintained polarizing air–liquid interface (ALI) to maintain differentiation. Traditional methods rely on permeable membrane culture inserts, which are difficult to work with and are ill-suited for the production of large numbers of cells, such as the quantities required for cell-based clinical therapies. Herein, we investigate an alternative form of culture in which the cells are placed on a porous substrate that is continuously rolled, such that the monolayer of cells is alternately submerged in media or apically exposed to air. Our prototype bioreactor is reliable for up to 21 days of continuous culture and is designed for scale-up for large-scale cell culture with continuous medium and gas exchange. Normal human bronchial epithelial (NHBE) cells were cultured on an absorbent substrate in the reactor for periods of 7, 14, and 21 days and were compared to static controls that were submerged in media. Quantification by immunohistochemistry and quantitative PCR of markers specific to differentiated respiratory epithelium indicated increased cilia, mucous production, and tight junction formation in the rolled cultures, compared to static. Together with scanning electron microscopy and paraffin histology, the data indicate that the intermittent ALI provided by the rolling bioreactor promotes a polarized epithelial phenotype over a period of 21 days. PMID:26858899

  10. Bio-reactor chamber

    NASA Technical Reports Server (NTRS)

    Chandler, Joseph A. (Inventor)

    1989-01-01

    A bioreactor for cell culture is disclosed which provides for the introduction of fresh medium without excessive turbulent action. The fresh medium enters the bioreactor through a filter with a backwash action which prevents the cells from settling on the filter. The bioreactor is sealed and depleted medium is forced out of the container as fresh medium is added.

  11. Cell culture for three-dimensional modeling in rotating-wall vessels: an application of simulated microgravity

    NASA Technical Reports Server (NTRS)

    Schwarz, R. P.; Goodwin, T. J.; Wolf, D. A.

    1992-01-01

    High-density, three-dimensional cell cultures are difficult to grow in vitro. The rotating-wall vessel (RWV) described here has cultured BHK-21 cells to a density of 1.1 X 10(7) cells/ml. Cells on microcarriers were observed to grow with enhanced bridging in this batch culture system. The RWV is a horizontally rotated tissue culture vessel with silicon membrane oxygenation. This design results in a low-turbulence, low-shear cell culture environment with abundant oxygenation. The RWV has the potential to culture a wide variety of normal and neoplastic cells.

  12. Three-dimensional transgenic cell model to quantify genotoxic effects of space environment

    NASA Astrophysics Data System (ADS)

    Gonda, S. R.; Wu, H.; Pingerelli, P. L.; Glickman, B. W.

    In this paper we describe a three-dimensional, multicellular tissue-equivalent model, produced in NASA-designed, rotating wall bioreactors using mammalian cells engineered for genomic containment of multiple copies of defined target genes for genotoxic assessment. Rat 2λ fibroblasts, genetically engineered to contain high-density target genes for mutagenesis (Stratagene, Inc., Austin, TX), were cocultured with human epithelial cells on Cytodex beads in the High Aspect Ratio Bioreactor (Synthecon, Inc, Houston, TX). Multi-bead aggregates were formed by day 5 following the complete covering of the beads by fibroblasts. Cellular retraction occurred 8-14 days after coculture initiation culminating in spheroids retaining few or no beads. Analysis of the resulting tissue assemblies revealed: multicellular spheroids, fibroblasts synthesized collagen, and cell viability was retained for the 30-day test period after removal from the bioreactor. Quantification of mutation at the LacI gene in Rat 2λ fibroblasts in spheroids exposed to 0-2 Gy neon using the Big Blue color assay (Stratagene, Inc.), revealed a linear dose-response for mutation induction. Limited sequencing analysis of mutant clones from 0.25 or 1 Gy exposures revealed a higher frequency of deletions and multiple base sequencing changes with increasing dose. These results suggest that the three-dimensional, multicellular tissue assembly model produced in NASA bioreactors are applicable to a wide variety of studies involving the quantification and identification of genotocity including measurement of the inherent damage incurred in Space.

  13. Oscillating Cell Culture Bioreactor

    NASA Technical Reports Server (NTRS)

    Freed, Lisa E.; Cheng, Mingyu; Moretti, Matteo G.

    2010-01-01

    To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid

  14. A wall interference assessment/correction interface measurement system for the NASA/ARC 12-ft PWT

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Development of complex air vehicle configurations is placing increasing demands on wind tunnel testing capabilities. A major area of concern is wall induced interference. Recent developments in wall interference technology provide a means for assessing and correcting for the wall induced interference using information contained in the distribution of flow variables measured at, or near, the wall. The restoration of the NASA-ARC 12-ft pressure wind tunnel (PWT) provides an opportunity to incorporate a measurement system with which wall interference assessment/correction (WIAC) technology can be applied. In this first phase of the development of a WIAC system for the PWT, the design criteria for the placement and the geometry of wall static pressure orifices were determined with a three step approach. First, the operational environment of the PWT was analyzed as to the requirements for the WIAC system. Second, appropriate wall interference theories were evaluated against the requirements determined from the operational environment. Third, the flow about representative models in the PWT was calculated and, specifically, the pressure signatures at the location of the test section wall were obtained. The number of discrete pressure measurements and their locations were determined by curve fitting the pressure distribution through the discrete measurements and evaluating the resulting error.

  15. Micro-CT Sections and Histological Sections of Mouse Skull Defects Implanted with Cartilage Grown in a Rotating Bioreactor

    NASA Astrophysics Data System (ADS)

    Duke, P. J.; Montufar-Solis, D.; Nguyen, H. C.; Cody, D. D.

    2008-06-01

    Using cartilage to replace/repair bone is advantageous as no scaffolding is required to form the implant which disappears as bone is formed during the endochondral process. Previously, we demonstrated that cartilage spheroids, grown in a rotating bioreactor, (Synthecon, Inc.) and implanted into a 2 mm skull defect, contributed to healing of the defect. In this report, skulls with or without implants were subjected to microCT scans, and sections from these scans were compared to histological sections of the defect region of demineralized skulls from the same experiment. The area of the defect staining for bone in histological sections of demineralized skulls was the same region shown as mineralized in CT sections. Defects without implants were shown in serial CT sections and histological sections, to be incompletely healed. This study demonstrates that microCT scans are an important corollary to histological studies evaluating the use of implants in healing of bony defects. Supported in part by NIH/NIDCR Training Grant T35 DE07252 and by Cancer Center Support Grant (CA-16672).

  16. A double chamber rotating bioreactor for enhanced tubular tissue generation from human mesenchymal stem cells: a promising tool for vascular tissue regeneration.

    PubMed

    Stefani, I; Asnaghi, M A; Cooper-White, J J; Mantero, S

    2018-01-01

    Cardiovascular diseases represent a major global health burden, with high rates of mortality and morbidity. Autologous grafts are commonly used to replace damaged or failing blood vessels; however, such approaches are hampered by the scarcity of suitable graft tissue, donor site morbidity and poor long-term stability. Tissue engineering has been investigated as a means by which exogenous vessel grafts can be produced, with varying levels of success to date, a result of mismatched mechanical properties of these vessel substitutes and inadequate ex vivo vessel tissue genesis. In this work, we describe the development of a novel multifunctional dual-phase (air/aqueous) bioreactor, designed to both rotate and perfuse small-diameter tubular scaffolds and encourage enhanced tissue genesis throughout such scaffolds. Within this novel dynamic culture system, an elastomeric nanofibrous, microporous composite tubular scaffold, composed of poly(caprolactone) and acrylated poly(lactide-co-trimethylene-carbonate) and with mechanical properties approaching those of native vessels, was seeded with human mesenchymal stem cells (hMSCs) and cultured for up to 14 days in inductive (smooth muscle) media. This scaffold/bioreactor combination provided a dynamic culture environment that enhanced (compared with static controls) scaffold colonization, cell growth, extracellular matrix deposition and in situ differentiation of the hMSCs into mature smooth muscle cells, representing a concrete step towards our goal of creating a mature ex vivo vascular tissue for implantation. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Microgravity

    NASA Image and Video Library

    1998-10-10

    Epithelial cell monoculture: Long-term growth of human mammary epithelial cells (HMEC) grown in monoculture as 3-dimensional constructions in the presence of attachment beads in the NASA Bioreactor. A: A typical construct about 3.5 mm (less than 1/8th inch) in diameter with slightly dehydrted, crinkled beads contained on the surface as well as within the 3-dimensional structure. B: The center of these constructs is hollow. Crinkling of the beads causes a few to fall out, leaving crater-like impressiions in the construct. The central impression shows a small hole that accesses the hollow center of the construct. C: A closeup view of the cells and the hole the central impression. D: Closer views of cells in the construct showing sell-to-cell interactions. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Richmond, NASA/Marshall Space Flight Center (MSFC).

  18. Bioreactor cultivation enhances NTEB formation and differentiation of NTES cells into cardiomyocytes.

    PubMed

    Lü, Shuanghong; Liu, Sheng; He, Wenjun; Duan, Cuimi; Li, Yanmin; Liu, Zhiqiang; Zhang, Ye; Hao, Tong; Wang, Yanmeng; Li, Dexue; Wang, Changyong; Gao, Shaorong

    2008-09-01

    Autogenic embryonic stem cells established from somatic cell nuclear transfer (SCNT) embryos have been proposed as unlimited cell sources for cell transplantation-based treatment of many genetic and degenerative diseases, which can eliminate the immune rejection that occurs after transplantation. In the present study, pluripotent nuclear transfer ES (NTES) cell lines were successfully established from different strains of mice. One NTES cell line, NT1, with capacity of germline transmission, was used to investigate in vitro differentiation into cardiomyocytes. To optimize differentiation conditions for mass production of embryoid bodies (NTEBs) from NTES cells, a slow-turning lateral vessel (STLV) rotating bioreactor was used for culturing the NTES cells to produce NTEBs compared with a conventional static cultivation method. Our results demonstrated that the NTEBs formed in STLV bioreactor were more uniform in size, and no large necrotic centers with most of the cells in NTEBs were viable. Differentiation of the NTEBs formed in both the STLV bioreactor and static culture into cardiomyocytes was induced by ascorbic acid, and the results demonstrated that STLV-produced NTEBs differentiated into cardiomyocytes more efficiently. Taken together, our results suggested that STLV bioreactor provided a more ideal culture condition, which can facilitate the formation of better quality NTEBs and differentiation into cardiomyocytes more efficiently in vitro.

  19. Impact of wall shear stress on initial bacterial adhesion in rotating annular reactor

    PubMed Central

    Saur, Thibaut; Morin, Emilie; Habouzit, Frédéric; Bernet, Nicolas

    2017-01-01

    The objective of this study was to investigate the bacterial adhesion under different wall shear stresses in turbulent flow and using a diverse bacterial consortium. A better understanding of the mechanisms governing microbial adhesion can be useful in diverse domains such as industrial processes, medical fields or environmental biotechnologies. The impact of wall shear stress—four values ranging from 0.09 to 7.3 Pa on polypropylene (PP) and polyvinyl chloride (PVC)—was carried out in rotating annular reactors to evaluate the adhesion in terms of morphological and microbiological structures. A diverse inoculum consisting of activated sludge was used. Epifluorescence microscopy was used to quantitatively and qualitatively characterize the adhesion. Attached bacterial communities were assessed by molecular fingerprinting profiles (CE-SSCP). It has been demonstrated that wall shear stress had a strong impact on both quantitative and qualitative aspects of the bacterial adhesion. ANOVA tests also demonstrated the significant impact of wall shear stress on all three tested morphological parameters (surface coverage, number of objects and size of objects) (p-values < 2.10−16). High wall shear stresses increased the quantity of attached bacteria but also altered their spatial distribution on the substratum surface. As the shear increased, aggregates or clusters appeared and their size grew when increasing the shears. Concerning the microbiological composition, the adhered bacterial communities changed gradually with the applied shear. PMID:28207869

  20. A method for the estimate of the wall diffusion for non-axisymmetric fields using rotating external fields

    NASA Astrophysics Data System (ADS)

    Frassinetti, L.; Olofsson, K. E. J.; Fridström, R.; Setiadi, A. C.; Brunsell, P. R.; Volpe, F. A.; Drake, J.

    2013-08-01

    A new method for the estimate of the wall diffusion time of non-axisymmetric fields is developed. The method based on rotating external fields and on the measurement of the wall frequency response is developed and tested in EXTRAP T2R. The method allows the experimental estimate of the wall diffusion time for each Fourier harmonic and the estimate of the wall diffusion toroidal asymmetries. The method intrinsically considers the effects of three-dimensional structures and of the shell gaps. Far from the gaps, experimental results are in good agreement with the diffusion time estimated with a simple cylindrical model that assumes a homogeneous wall. The method is also applied with non-standard configurations of the coil array, in order to mimic tokamak-relevant settings with a partial wall coverage and active coils of large toroidal extent. The comparison with the full coverage results shows good agreement if the effects of the relevant sidebands are considered.

  1. Rotationally resolved colors of the targets of NASA's Lucy mission

    NASA Astrophysics Data System (ADS)

    Emery, Joshua; Mottola, Stefano; Brown, Mike; Noll, Keith; Binzel, Richard

    2018-05-01

    We propose rotationally resolved photometry at 3.6 and 4.5 um of 5 Trojan asteroids and one Main Belt asteroid - the targets of NASA's Lucy mission. The proposed Spitzer observations are designed to meet a combination of science goals and mission support objectives. Science goals 1) Search for signatures of volatiles and/or organics on the surfaces. a. This goal includes resolving a discrepancy between previous WISE and Spitzer measurements of Trojans 2) Provide new constraints on the cause of rotational spectral heterogeneity detected on 3548 Eurybates at shorter wavelengths a. Determine whether the heterogeneity (Fig 1) extends to the 3-5 um region 3) Assess the possibility for spectral heterogeneity on the other targets a. This goal will help test the hypothesis of Wong and Brown (2015) that the near-surface interiors of Trojans differ from their surfaces 4) Thermal data at 4.5 um for the Main Belt target Donaldjohanson will refine estimates of size, albedo, and provide the first estimate of thermal inertia Mission support objectives 1) Assess scientifically optimal encounter times (viewing geometries) for the fly-bys a. Characterizing rotational spectral units now will enable the team to choose the most scientifically valuable part of the asteroid to view 2) Gather data to optimize observing parameters for Lucy instruments a. Measuring brightness in the 3 - 5 um region and resolving the discrepancy between WISE and Spitzer will enable better planning of the Lucy spectral observations in this wavelength range 3) The size, albedo, and thermal inertia of Donaldjohanson are fundamental data for planning the encounter with that Main Belt asteroid

  2. Construction of a 2- by 2-foot transonic adaptive-wall test section at the NASA Ames Research Center

    NASA Technical Reports Server (NTRS)

    Morgan, Daniel G.; Lee, George

    1986-01-01

    The development of a new production-size, two-dimensional, adaptive-wall test section with ventilated walls at the NASA Ames Research Center is described. The new facility incorporates rapid closed-loop operation, computer/sensor integration, and on-line interference assessment and wall corrections. Air flow through the test section is controlled by a series of plenum compartments and three-way slide vales. A fast-scan laser velocimeter was built to measure velocity boundary conditions for the interference assessment scheme. A 15.2-cm- (6.0-in.-) chord NACA 0012 airfoil model will be used in the first experiments during calibration of the facility.

  3. Bioreactor design concepts

    NASA Technical Reports Server (NTRS)

    Bowie, William

    1987-01-01

    Two parallel lines of work are underway in the bioreactor laboratory. One of the efforts is devoted to the continued development and utilization of a laboratory research system. That system's design is intended to be fluid and dynamic. The sole purpose of such a device is to allow testing and development of equipment concepts and procedures. Some of the results of those processes are discussed. A second effort is designed to produce a flight-like bioreactor contained in a double middeck locker. The result of that effort has been to freeze a particular bioreactor design in order to allow fabrication of the custom parts. The system is expected to be ready for flight in early 1988. However, continued use of the laboratory system will lead to improvements in the space bioreactor. Those improvements can only be integrated after the initial flight series.

  4. Mixed convection heat transfer enhancement in a cubic lid-driven cavity containing a rotating cylinder through the introduction of artificial roughness on the heated wall

    NASA Astrophysics Data System (ADS)

    Kareem, Ali Khaleel; Gao, Shian

    2018-02-01

    The aim of the present numerical investigation is to comprehensively analyse and understand the heat transfer enhancement process using a roughened, heated bottom wall with two artificial rib types (R-s and R-c) due to unsteady mixed convection heat transfer in a 3D moving top wall enclosure that has a central rotating cylinder, and to compare these cases with the smooth bottom wall case. These different cases (roughened and smooth bottom walls) are considered at various clockwise and anticlockwise rotational speeds, -5 ≤ Ω ≤ 5, and Reynolds numbers of 5000 and 10 000. The top and bottom walls of the lid-driven cavity are differentially heated, whilst the remaining cavity walls are assumed to be stationary and adiabatic. A standard k-ɛ model for the Unsteady Reynolds-Averaged Navier-Stokes equations is used to deal with the turbulent flow. The heat transfer improvement is carefully considered and analysed through the detailed examinations of the flow and thermal fields, the turbulent kinetic energy, the mean velocity profiles, the wall shear stresses, and the local and average Nusselt numbers. It has been concluded that artificial roughness can strongly affect the thermal fields and fluid flow patterns. Ultimately, the heat transfer rate has been dramatically increased by involving the introduced artificial rips. Increasing the cylinder rotational speed or Reynolds number can enhance the heat transfer process, especially when the wall roughness exists.

  5. A Versatile Bioreactor for Dynamic Suspension Cell Culture. Application to the Culture of Cancer Cell Spheroids

    PubMed Central

    Madeddu, Denise; Cerino, Giulia; Falco, Angela; Frati, Caterina; Gallo, Diego; Deriu, Marco A.; Falvo D’Urso Labate, Giuseppe; Quaini, Federico; Audenino, Alberto; Morbiducci, Umberto

    2016-01-01

    A versatile bioreactor suitable for dynamic suspension cell culture under tunable shear stress conditions has been developed and preliminarily tested culturing cancer cell spheroids. By adopting simple technological solutions and avoiding rotating components, the bioreactor exploits the laminar hydrodynamics establishing within the culture chamber enabling dynamic cell suspension in an environment favourable to mass transport, under a wide range of tunable shear stress conditions. The design phase of the device has been supported by multiphysics modelling and has provided a comprehensive analysis of the operating principles of the bioreactor. Moreover, an explanatory example is herein presented with multiphysics simulations used to set the proper bioreactor operating conditions for preliminary in vitro biological tests on a human lung carcinoma cell line. The biological results demonstrate that the ultralow shear dynamic suspension provided by the device is beneficial for culturing cancer cell spheroids. In comparison to the static suspension control, dynamic cell suspension preserves morphological features, promotes intercellular connection, increases spheroid size (2.4-fold increase) and number of cycling cells (1.58-fold increase), and reduces double strand DNA damage (1.5-fold reduction). It is envisioned that the versatility of this bioreactor could allow investigation and expansion of different cell types in the future. PMID:27144306

  6. A Versatile Bioreactor for Dynamic Suspension Cell Culture. Application to the Culture of Cancer Cell Spheroids.

    PubMed

    Massai, Diana; Isu, Giuseppe; Madeddu, Denise; Cerino, Giulia; Falco, Angela; Frati, Caterina; Gallo, Diego; Deriu, Marco A; Falvo D'Urso Labate, Giuseppe; Quaini, Federico; Audenino, Alberto; Morbiducci, Umberto

    2016-01-01

    A versatile bioreactor suitable for dynamic suspension cell culture under tunable shear stress conditions has been developed and preliminarily tested culturing cancer cell spheroids. By adopting simple technological solutions and avoiding rotating components, the bioreactor exploits the laminar hydrodynamics establishing within the culture chamber enabling dynamic cell suspension in an environment favourable to mass transport, under a wide range of tunable shear stress conditions. The design phase of the device has been supported by multiphysics modelling and has provided a comprehensive analysis of the operating principles of the bioreactor. Moreover, an explanatory example is herein presented with multiphysics simulations used to set the proper bioreactor operating conditions for preliminary in vitro biological tests on a human lung carcinoma cell line. The biological results demonstrate that the ultralow shear dynamic suspension provided by the device is beneficial for culturing cancer cell spheroids. In comparison to the static suspension control, dynamic cell suspension preserves morphological features, promotes intercellular connection, increases spheroid size (2.4-fold increase) and number of cycling cells (1.58-fold increase), and reduces double strand DNA damage (1.5-fold reduction). It is envisioned that the versatility of this bioreactor could allow investigation and expansion of different cell types in the future.

  7. Evaluating the Acoustic Effect of Over-the-Rotor Foam-Metal Liner Installed on a Low Speed Fan Using Virtual Rotating Microphone Imaging

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; Dougherty, Robert P.; Walker, Bruce E.

    2010-01-01

    An in-duct beamforming technique for imaging rotating broadband fan sources has been used to evaluate the acoustic characteristics of a Foam-Metal Liner installed over-the-rotor of a low-speed fan. The NASA Glenn Research Center s Advanced Noise Control Fan was used as a test bed. A duct wall-mounted phased array consisting of several rings of microphones was employed. The data are mathematically resampled in the fan rotating reference frame and subsequently used in a conventional beamforming technique. The steering vectors for the beamforming technique are derived from annular duct modes, so that effects of reflections from the duct walls are reduced.

  8. Unique cell culture systems for ground based research

    NASA Technical Reports Server (NTRS)

    Lewis, Marian L.

    1990-01-01

    The horizontally rotating fluid-filled, membrane oxygenated bioreactors developed at NASA Johnson for spacecraft applications provide a powerful tool for ground-based research. Three-dimensional aggregates formed by cells cultured on microcarrier beads are useful for study of cell-cell interactions and tissue development. By comparing electron micrographs of plant seedlings germinated during Shuttle flight 61-C and in an earth-based rotating bioreactor it is shown that some effects of microgravity are mimicked. Bioreactors used in the UAH Bioreactor Laboratory will make it possible to determine some of the effects of altered gravity at the cellular level. Bioreactors can be valuable for performing critical, preliminary-to-spaceflight experiments as well as medical investigations such as in vitro tumor cell growth and chemotherapeutic drug response; the enrichment of stem cells from bone marrow; and the effect of altered gravity on bone and muscle cell growth and function and immune response depression.

  9. Design challenges for space bioreactors

    NASA Technical Reports Server (NTRS)

    Seshan, P. K.; Petersen, G. R.

    1989-01-01

    The design of bioreactors for operation under conditions of microgravity presents problems and challenges. Absence of a significant body force such as gravity can have profound consequences for interfacial phenomena. Marangoni convection can no longer be overlooked. Many speculations on the advantages and benefits of microgravity can be found in the literature. Initial bioreactor research considerations for space applications had little regard for the suitability of the designs for conditions of microgravity. Bioreactors can be classified in terms of their function and type of operation. The complex interaction of parameters leading to optimal design and operation of a bioreactor is illustrated by the JSC mammalian cell culture system. The design of a bioreactor is strongly dependent upon its intended use as a production unit for cell mass and/or biologicals or as a research reactor for the study of cell growth and function. Therefore a variety of bioreactor configurations are presented in rapid summary. Following this, a rationale is presented for not attempting to derive key design parameters such as the oxygen transfer coefficient from ground-based data. A set of themes/objectives for flight experiments to develop the expertise for design of space bioreactors is then proposed for discussion. These experiments, carried out systematically, will provide a database from which engineering tools for space bioreactor design will be derived.

  10. Wall shear stress measurement in blade end-wall corner region

    NASA Technical Reports Server (NTRS)

    Bhargava, R.; Raj, R.; Boldman, D. R.

    1987-01-01

    The magnitude and the direction of wall shear stress and surface pressure in the blade end-wall corner region were investigated. The measurements were obtained on a specially designed Preston tube, the tip of which could be concentrically rotated about its axis of rotation at the measurement location. The magnitude of wall shear stress in the vicinity of the corner was observed to increase significantly (170 percent) compared to its far-upstream value; the increase was consistently higher on the blade surface compared to the value on the plate surface of the blade end-wall corner. On both surfaces in the blade end-wall corner, the variation of the wall shear stress direction was found to be more predominant in the vicinity of the blade leading-edge location. The trend of the measured wall shear stress direction showed good agreement with the limiting streamline directions obtained from the flow visualization studies.

  11. Effects of curvature and rotation on turbulence in the NASA low-speed centrifugal compressor impeller

    NASA Technical Reports Server (NTRS)

    Moore, Joan G.; Moore, John

    1992-01-01

    The flow in the NASA Low-Speed Impeller is affected by both curvature and rotation. The flow curves due to the following: (1) geometric curvature, e.g. the curvature of the hub and shroud profiles in the meridional plane and the curvature of the backswept impeller blades; and (2) secondary flow vortices, e.g. the tip leakage vortex. Changes in the turbulence and effective turbulent viscosity in the impeller are investigated. The effects of these changes on three-dimensional flow development are discussed. Two predictions of the flow in the impeller, one with, and one without modification to the turbulent viscosity due to rotation and curvature, are compared. Some experimental and theoretical background for the modified mixing length model of turbulent viscosity will also be presented.

  12. Denitrification 'Woodchip' Bioreactors for Productive and Sustainable Agricultural Systems

    NASA Astrophysics Data System (ADS)

    Christianson, L. E.; Summerfelt, S.; Sharrer, K.; Lepine, C.; Helmers, M. J.

    2014-12-01

    Growing alarm about negative cascading effects of reactive nitrogen in the environment has led to multifaceted efforts to address elevated nitrate-nitrogen levels in water bodies worldwide. The best way to mitigate N-related impacts, such as hypoxic zones and human health concerns, is to convert nitrate to stable, non-reactive dinitrogen gas through the natural process of denitrification. This means denitrification technologies need to be one of our major strategies for tackling the grand challenge of managing human-induced changes to our global nitrogen cycle. While denitrification technologies have historically been focused on wastewater treatment, there is great interest in new lower-tech options for treating effluent and drainage water from one of our largest reactive nitrogen emitters -- agriculture. Denitrification 'woodchip' bioreactors are able to enhance this natural N-conversion via addition of a solid carbon source (e.g., woodchips) and through designs that facilitate development of anoxic conditions required for denitrification. Wood-based denitrification technologies such as woodchip bioreactors and 'sawdust' walls for groundwater have been shown to be effective at reducing nitrate loads in agricultural settings around the world. Designing these systems to be low-maintenance and to avoid removing land from agricultural production has been a primary focus of this "farmer-friendly" technology. This presentation provides a background on woodchip bioreactors including design considerations, N-removal performance, and current research worldwide. Woodchip bioreactors for the agricultural sector are an accessible new option to address society's interest in improving water quality while simultaneously allowing highly productive agricultural systems to continue to provide food in the face of increasing demand, changing global diets, and fluctuating weather.

  13. A Dual-Mode Bioreactor System for Tissue Engineered Vascular Models.

    PubMed

    Bono, N; Meghezi, S; Soncini, M; Piola, M; Mantovani, D; Fiore, Gianfranco Beniamino

    2017-06-01

    In the past decades, vascular tissue engineering has made great strides towards bringing engineered vascular tissues to the clinics and, in parallel, obtaining in-lab tools for basic research. Herein, we propose the design of a novel dual-mode bioreactor, useful for the fabrication (construct mode) and in vitro stimulation (culture mode) of collagen-based tubular constructs. Collagen-based gels laden with smooth muscle cells (SMCs) were molded directly within the bioreactor culture chamber. Based on a systematic characterization of the bioreactor culture mode, constructs were subjected to 10% cyclic strain at 0.5 Hz for 5 days. The effects of cyclic stimulation on matrix re-arrangement and biomechanical/viscoelastic properties were examined and compared vs. statically cultured constructs. A thorough comparison of cell response in terms of cell localization and expression of contractile phenotypic markers was carried out as well. We found that cyclic stimulation promoted cell-driven collagen matrix bi-axial compaction, enhancing the mechanical strength of strained samples with respect to static controls. Moreover, cyclic strain positively affected SMC behavior: cells maintained their contractile phenotype and spread uniformly throughout the whole wall thickness. Conversely, static culture induced a noticeable polarization of cell distribution to the outer rim of the constructs and a sharp reduction in total cell density. Overall, coupling the use of a novel dual-mode bioreactor with engineered collagen-gel-based tubular constructs demonstrated to be an interesting technology to investigate the modulation of cell and tissue behavior under controlled mechanically conditioned in vitro maturation.

  14. Radio Frequency (RF) Trap for Confinement of Antimatter Plasmas Using Rotating Wall Electric Fields

    NASA Technical Reports Server (NTRS)

    Sims, William Herbert, III; Pearson, J. Boise

    2004-01-01

    Perturbations associated with a rotating wall electric field enable the confinement of ions for periods approaching weeks. This steady state confinement is a result of a radio frequency manipulation of the ions. Using state-of-the-art techniques it is shown that radio frequency energy can produce useable manipulation of the ion cloud (matter or antimatter) for use in containment experiments. The current research focuses on the improvement of confinement systems capable of containing and transporting antimatter.

  15. The Real-Time Wall Interference Correction System of the NASA Ames 12-Foot Pressure Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Ulbrich, Norbert

    1998-01-01

    An improved version of the Wall Signature Method was developed to compute wall interference effects in three-dimensional subsonic wind tunnel testing of aircraft models in real-time. The method may be applied to a full-span or a semispan model. A simplified singularity representation of the aircraft model is used. Fuselage, support system, propulsion simulator, and separation wake volume blockage effects are represented by point sources and sinks. Lifting effects are represented by semi-infinite line doublets. The singularity representation of the test article is combined with the measurement of wind tunnel test reference conditions, wall pressure, lift force, thrust force, pitching moment, rolling moment, and pre-computed solutions of the subsonic potential equation to determine first order wall interference corrections. Second order wall interference corrections for pitching and rolling moment coefficient are also determined. A new procedure is presented that estimates a rolling moment coefficient correction for wings with non-symmetric lift distribution. Experimental data obtained during the calibration of the Ames Bipod model support system and during tests of two semispan models mounted on an image plane in the NASA Ames 12 ft. Pressure Wind Tunnel are used to demonstrate the application of the wall interference correction method.

  16. Osteoradionecrosis of the chest wall. Management of postresection defects using Marlex mesh and a rotated latissimus dorsi myocutaneous flap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hines, G.L.; Lee, G.

    1983-11-01

    Full thickness chest wall resection and single stage reconstruction for osteoradionecrosis of the chest wall was performed on five patients. All patients had undergone radical mastectomy and radiation therapy from 5 to 18 years prior to chest wall resection. Defects varied from 12 X 5 cm to 15 X 15 cm, and included from two to four ribs. Reconstruction was performed using Marlex mesh to reconstruct the bony thorax and a rotated latissimus dorsi myocutaneous flap. Coverage was successfully performed in all cases, and no patient experienced postoperative pulmonary dysfunction. There were no complications related to either the bony thoraxmore » reconstruction or the latissimus flap. The use of this technique has provided a safe, convenient, and reliable method of chest wall reconstruction.« less

  17. Space bioreactor: Design/process flow

    NASA Technical Reports Server (NTRS)

    Cross, John H.

    1987-01-01

    The design of the space bioreactor stems from three considerations. First, and foremost, it must sustain cells in microgravity. Closely related is the ability to take advantage of the weightlessness and microgravity. Lastly, it should fit into a bioprocess. The design of the space bioreactor is described in view of these considerations. A flow chart of the bioreactor is presented and discussed.

  18. Influence of Zero-Shear on Yeast Development

    NASA Technical Reports Server (NTRS)

    McGinnis, Michael R.

    1997-01-01

    The objective of the research was to begin evaluating the effect of zero-shear on the development of the cell wall of Saccharomyces cerevisiae employing the High Aspect Rotating-Wall Vessel (HARV) NASA bioreactor. This particular yeast has enormous potential for research as a model eukaryotic system on the International Space Station, as well as the production of food stuffs' at the future lunar colony. Because the cell wall is the barrier between the cell and the environment, its form and function as influenced by microgravity is of great importance. Morphologic studies revealed that the circularity and total area of the individual yeast cells were essentially the same in both the control and test HARV's. The growth rates were also essentially the same. In zero-shear, the yeast grew in clumps consisting of rudimentary pseudohyphae in contrast to solitary budding cells in the control. Based upon mechanical and sonic shear applied to the yeast cells, those grown in zero-shear had stronger cell walls and septa. This suggests that there are structural differences, most likely related to the chitin skeleton of the cell wall. From this research further NASA support was obtained to continue the work. Investigations will deal with gene expression and ultrastructure. These will lead to a clearer assessment of the value of S. cerevisiae eukaryotic as a model for space station research.

  19. Space Bioreactor Science Workshop

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Editor)

    1987-01-01

    The first space bioreactor has been designed for microprocessor control, no gaseous headspace, circulation and resupply of culture medium, and a slow mixing in very low shear regimes. Various ground based bioreactors are being used to test reactor vessel design, on-line sensors, effects of shear, nutrient supply, and waste removal from continuous culture of human cells attached to microcarriers. The small (500 ml) bioreactor is being constructed for flight experiments in the Shuttle middeck to verify systems operation under microgravity conditions and to measure the efficiencies of mass transport, gas transfer, oxygen consumption, and control of low shear stress on cells. Applications of microcarrier cultures, development of the first space bioreactor flight system, shear and mixing effects on cells, process control, and methods to monitor cell metabolism and nutrient requirements are among the topics covered.

  20. Microbial Bioreactor Development in the ALS NSCORT

    NASA Astrophysics Data System (ADS)

    Mitchell, Cary; Whitaker, Dawn; Banks, M. Katherine; Heber, Albert J.; Turco, Ronald F.; Nies, Loring F.; Alleman, James E.; Sharvelle, Sybil E.; Li, Congna; Heller, Megan

    The NASA Specialized Center of Research and Training in Advanced Life Support (the ALS NSCORT), a partnership of Alabama A & M, Howard, and Purdue Universities, was established by NASA in 2002 to develop technologies that will reduce the Equivalent System Mass (ESM) of regenerative processes within future space life-support systems. A key focus area of NSCORT research has been the development of efficient microbial bioreactors for treatment of human, crop, and food-process wastes while enabling resource recovery. The approach emphasizes optimizing the energy-saving advantages of hydrolytic enzymes for biomass degradation, with focus on treatment of solid wastes including crop residue, paper, food, and human metabolic wastes, treatment of greywater, cabin air, off-gases from other treatment systems, and habitat condensate. This summary includes important findings from those projects, status of technology development, and recommendations for next steps. The Plant-based Anaerobic-Aerobic Bioreactor-Linked Operation (PAABLO) system was developed to reduce crop residue while generating energy and/or food. Plant residues initially were added directly to the bioreactor, and recalcitrant residue was used as a substrate for growing plants or mushrooms. Subsequently, crop residue was first pretreated with fungi to hydrolyze polymers recalcitrant to bacteria, and leachate from the fungal beds was directed to the anaerobic digester. Exoenzymes from the fungi pre-soften fibrous plant materials, improving recovery of materials that are more easily biodegraded to methane that can be used for energy reclamation. An Autothermal Thermophilic Aerobic Digestion (ATAD) system was developed for biodegradable solid wastes. Objectives were to increase water and nutrient recovery, reduce waste volume, and inactivate pathogens. Operational parameters of the reactor were optimized for degradation and resource recovery while minimizing system requirements and footprint. The start-up behavior

  1. Rotating shielded crane system

    DOEpatents

    Commander, John C.

    1988-01-01

    A rotating, radiation shielded crane system for use in a high radiation test cell, comprises a radiation shielding wall, a cylindrical ceiling made of radiation shielding material and a rotatable crane disposed above the ceiling. The ceiling rests on an annular ledge intergrally attached to the inner surface of the shielding wall. Removable plugs in the ceiling provide access for the crane from the top of the ceiling into the test cell. A seal is provided at the interface between the inner surface of the shielding wall and the ceiling.

  2. Simulated Microgravity Regulates Gene Transcript Profiles of 2T3 Preosteoblasts: Comparison of the Random Positioning Machine and the Rotating Wall Vessel Bioreactor

    NASA Technical Reports Server (NTRS)

    Patel, Mamta J.; Liu, Wenbin; Sykes, Michelle C.; Ward, Nancy E.; Risin, Semyon A.; Risin, Diana; Hanjoong, Jo

    2007-01-01

    Microgravity of spaceflight induces bone loss due in part to decreased bone formation by osteoblasts. We have previously examined the microgravity-induced changes in gene expression profiles in 2T3 preosteoblasts using the Random Positioning Machine (RPM) to simulate microgravity conditions. Here, we hypothesized that exposure of preosteoblasts to an independent microgravity simulator, the Rotating Wall Vessel (RWV), induces similar changes in differentiation and gene transcript profiles, resulting in a more confined list of gravi-sensitive genes that may play a role in bone formation. In comparison to static 1g controls, exposure of 2T3 cells to RWV for 3 days inhibited alkaline phosphatase activity, a marker of differentiation, and downregulated 61 genes and upregulated 45 genes by more than two-fold as shown by microarray analysis. The microarray results were confirmed with real time PCR for downregulated genes osteomodulin, bone morphogenic protein 4 (BMP4), runx2, and parathyroid hormone receptor 1. Western blot analysis validated the expression of three downregulated genes, BMP4, peroxiredoxin IV, and osteoglycin, and one upregulated gene peroxiredoxin I. Comparison of the microarrays from the RPM and the RWV studies identified 14 gravi-sensitive genes that changed in the same direction in both systems. Further comparison of our results to a published database showing gene transcript profiles of mechanically loaded mouse tibiae revealed 16 genes upregulated by the loading that were shown to be downregulated by RWV and RPM. These mechanosensitive genes identified by the comparative studies may provide novel insights into understanding the mechanisms regulating bone formation and potential targets of countermeasure against decreased bone formation both in astronauts and in general patients with musculoskeletal disorders.

  3. Bone Biomarkers on the Pathway to Effective Spaceflight Countermeasures

    NASA Technical Reports Server (NTRS)

    Spatz, Jordan

    2009-01-01

    Osteocyte cells are the most abundant yet least understood bone cell type in the human body. However, recent discovers in osteocyte cell biology have shed light on their importance as key mechanosensing cells regulating the bone remodeling process. Thus, we propose the first ever in vitro gene expression evaluation of osteocytes exposed to simulated microgravity to determine mechanistic pathways of their gravity sensing ability. Improved understanding of the fundamental mechanisms at the osteocyte cellular level may lead to improved treatment options to mitigate the effects of bone loss encountered by astronauts on long duration space missions and provide tailored treatment options for maintaining bone strength of immobilized/partially paralyzed patients here on Earth. Aim 1: Characterize the gene expression patterns and protein levels following exposure of murine osteocytelike cell line (MLO-Y4) to simulated microgravity using the NASA Rotating Wall Vessel (RWV) Bioreactor. Osteocytes are theorized to be the mechanosensors and transducers of mechanical load for bones, yet the biological mechanism of this action remains elusive. We propose to investigate the genetic regulation of the mechanism of the MLO-Y4 cell in the NASA Bioreactor as it is the accepted ground-based analog for simulating vector averaged microgravity.

  4. Integrated modeling of temperature and rotation profiles in JET ITER-like wall discharges

    NASA Astrophysics Data System (ADS)

    Rafiq, T.; Kritz, A. H.; Kim, Hyun-Tae; Schuster, E.; Weiland, J.

    2017-10-01

    Simulations of 78 JET ITER-like wall D-D discharges and 2 D-T reference discharges are carried out using the TRANSP predictive integrated modeling code. The time evolved temperature and rotation profiles are computed utilizing the Multi-Mode anomalous transport model. The discharges involve a broad range of conditions including scans over gyroradius, collisionality, and values of q95. The D-T reference discharges are selected in anticipation of the D-T experimental campaign planned at JET in 2019. The simulated temperature and rotation profiles are compared with the corresponding experimental profiles in the radial range from the magnetic axis to the ρ = 0.9 flux surface. The comparison is quantified by calculating the RMS deviations and Offsets. Overall, good agreement is found between the profiles produced in the simulations and the experimental data. It is planned that the simulations obtained using the Multi-Mode model will be compared with the simulations using the TGLF model. Research supported in part by the US, DoE, Office of Sciences.

  5. Rotation-excited perfect oscillation of a tri-walled nanotube-based oscillator at ultralow temperature

    NASA Astrophysics Data System (ADS)

    Cai, Kun; Zhang, Xiaoni; Shi, Jiao; Qin, Qing H.

    2017-04-01

    In recent years, carbon-nanotube (CNT)-based gigahertz oscillators have been widely used in numerous areas of practical engineering such as high-speed digital, analog circuits, and memory cells. One of the major challenges to practical applications of the gigahertz oscillator is generating a stable oscillation process from the gigahertz oscillators and then maintaining the stable process for a specified period of time. To address this challenge, an oscillator from a triple-walled CNT-based rotary system is proposed and analyzed numerically in this paper, using a molecular dynamics approach. In this system, the outer tube is fixed partly as a stator. The middle tube, with a constant rotation, is named Rotor 2 and runs in the stator. The inner tube acts as Rotor 1, which can rotate freely in Rotor 2. Due to the friction between the two rotors when they have relative motion, the rotational frequency of Rotor 1 increases continuously and tends to converge with that of Rotor 2. During rotation, the oscillation of Rotor 1 may be excited owing to both a strong end barrier at Rotor 2 and thermal vibration of atoms in the tubes. From the discussion on the effects of length of Rotor 1, temperature, and input rotational frequency of Rotor 2 on the dynamic response of Rotor 1, an effective way to control the oscillation of Rotor 1 is found. Being much longer than Rotor 2, Rotor 1 will have perfect oscillation, i.e., with both stable (or nearly constant) period and amplitude—especially at relatively low temperature. This discovery can be taken as a useful guidance for the design of an oscillator from CNTs.

  6. Rotation-excited perfect oscillation of a tri-walled nanotube-based oscillator at ultralow temperature.

    PubMed

    Cai, Kun; Zhang, Xiaoni; Shi, Jiao; Qin, Qing H

    2017-04-18

    In recent years, carbon-nanotube (CNT)-based gigahertz oscillators have been widely used in numerous areas of practical engineering such as high-speed digital, analog circuits, and memory cells. One of the major challenges to practical applications of the gigahertz oscillator is generating a stable oscillation process from the gigahertz oscillators and then maintaining the stable process for a specified period of time. To address this challenge, an oscillator from a triple-walled CNT-based rotary system is proposed and analyzed numerically in this paper, using a molecular dynamics approach. In this system, the outer tube is fixed partly as a stator. The middle tube, with a constant rotation, is named Rotor 2 and runs in the stator. The inner tube acts as Rotor 1, which can rotate freely in Rotor 2. Due to the friction between the two rotors when they have relative motion, the rotational frequency of Rotor 1 increases continuously and tends to converge with that of Rotor 2. During rotation, the oscillation of Rotor 1 may be excited owing to both a strong end barrier at Rotor 2 and thermal vibration of atoms in the tubes. From the discussion on the effects of length of Rotor 1, temperature, and input rotational frequency of Rotor 2 on the dynamic response of Rotor 1, an effective way to control the oscillation of Rotor 1 is found. Being much longer than Rotor 2, Rotor 1 will have perfect oscillation, i.e., with both stable (or nearly constant) period and amplitude-especially at relatively low temperature. This discovery can be taken as a useful guidance for the design of an oscillator from CNTs.

  7. Quantitative evaluation of the relationship between dorsal wall length, sole thickness, and rotation of the distal phalanx in the bovine claw using computed tomography.

    PubMed

    Tsuka, T; Murahata, Y; Azuma, K; Osaki, T; Ito, N; Okamoto, Y; Imagawa, T

    2014-10-01

    Computed tomography (CT) was performed on 800 untrimmed claws (400 inner claws and 400 outer claws) of 200 pairs of bovine hindlimbs to investigate the relationships between dorsal wall length and sole thickness, and between dorsal wall length and the relative rotation angle of distal phalanx-to-sole surface (S-D angle). Sole thickness was 3.8 and 4.0 mm at the apex of the inner claws and outer claws, respectively, with dorsal wall lengths <70 mm. These sole thickness values were less than the critical limit of 5 mm, which is associated with a softer surface following thinning of the soles. A sole thickness of 5 mm at the apex was estimated to correlate with dorsal wall lengths of 72.1 and 72.7 mm for the inner and outer claws, respectively. Sole thickness was 6.1 and 6.4 mm at the apex of the inner and outer claws, respectively, with dorsal wall lengths of 75 mm. These sole thickness values were less than the recommended sole thickness of 7 mm based on the protective function of the soles. A sole thickness >7 mm at the apex was estimated to correlate with a dorsal wall length of 79.8 and 78.4mm for the inner and outer claws, respectively. The S-D angles were recorded as anteversions of 2.9° and 4.7° for the inner and outer claws, respectively, with a dorsal wall length of 75 mm. These values indicate that the distal phalanx is likely to have rotated naturally forward toward the sole surface. The distal phalanx rotated backward to the sole surface at 3.2° and 7.6° for inner claws with dorsal wall lengths of 90-99 and ≥100 mm, respectively; and at 3.5° for outer claws with a dorsal wall length ≥100 mm. Dorsal wall lengths of 85.7 and 97.2 mm were estimated to correlate with a parallel positional relationship of the distal phalanx to the sole surface in the inner and outer claws, respectively. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. PRACTICE REVIEW OF FIVE BIOREACTOR/RECIRCULATION LANDFILLS

    EPA Science Inventory

    Six bioreactor landfills were analyzed to provide a perspective of current practice and technical issues that differentiate bioreactor landfills from conventional landfills. Five of the bioreactor landfills were anaerobic and one was aerated. In one case, nearly identical cells e...

  9. Three-Dimensional Cell Culture Models for Infectious Disease and Drug Development

    NASA Technical Reports Server (NTRS)

    Nickerson, Cheryl A.; Honer zu Bentrup, Kerstin; Ott, C. Mark

    2005-01-01

    Three-dimensional (3-D) cell cultures hold enormous potential to advance our understanding of infectious disease and to effectively translate basic cellular research into clinical applications. Using novel NASA bioreactor technology, the rotating wall vessel (RWV), we have engineered physiologically relevant 3-D human tissue culture models for infectious disease studies. The design of the RWV is based on the understanding that organs and tissues function in a 3-D environment, and that this 3-D architecture is critical for the differentiated form and function of tissues in vivo. The RWV provides large numbers of cells which are amenable to a wide variety of experimental manipulations and provides an easy, reproducible, and cost-effective approach to enhance differentiated features of cell culture models.

  10. Hydrostatic pressure and shear stress affect endothelin-1 and nitric oxide release by endothelial cells in bioreactors.

    PubMed

    Vozzi, Federico; Bianchi, Francesca; Ahluwalia, Arti; Domenici, Claudio

    2014-01-01

    Abundant experimental evidence demonstrates that endothelial cells are sensitive to flow; however, the effect of fluid pressure or pressure gradients that are used to drive viscous flow is not well understood. There are two principal physical forces exerted on the blood vessel wall by the passage of intra-luminal blood: pressure and shear. To analyze the effects of pressure and shear independently, these two stresses were applied to cultured cells in two different types of bioreactors: a pressure-controlled bioreactor and a laminar flow bioreactor, in which controlled levels of pressure or shear stress, respectively, can be generated. Using these bioreactor systems, endothelin-1 (ET-1) and nitric oxide (NO) release from human umbilical vein endothelial cells were measured under various shear stress and pressure conditions. Compared to the controls, a decrease of ET-1 production by the cells cultured in both bioreactors was observed, whereas NO synthesis was up-regulated in cells under shear stress, but was not modulated by hydrostatic pressure. These results show that the two hemodynamic forces acting on blood vessels affect endothelial cell function in different ways, and that both should be considered when planning in vitro experiments in the presence of flow. Understanding the individual and synergic effects of the two forces could provide important insights into physiological and pathological processes involved in vascular remodeling and adaptation. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Experimental Investigation of Rotating Stall in a Research Multistage Axial Compressor

    NASA Technical Reports Server (NTRS)

    Lepicovsky, Jan; Braunscheidel, Edward P.; Welch, Gerard E.

    2007-01-01

    A collection of experimental data acquired in the NASA low-speed multistage axial compressor while operated in rotating stall is presented in this paper. The compressor was instrumented with high-response wall pressure modules and a static pressure disc probe for in-flow measurement, and a split-fiber probe for simultaneous measurements of velocity magnitude and flow direction. The data acquired to-date have indicated that a single fully developed stall cell rotates about the flow annulus at 50.6% of the rotor speed. The stall phenomenon is substantially periodic at a fixed frequency of 8.29 Hz. It was determined that the rotating stall cell extends throughout the entire compressor, primarily in the axial direction. Spanwise distributions of the instantaneous absolute flow angle, axial and tangential velocity components, and static pressure acquired behind the first rotor are presented in the form of contour plots to visualize different patterns in the outer (midspan to casing) and inner (hub to mid-span) flow annuli during rotating stall. In most of the cases observed, the rotating stall started with a single cell. On occasion, rotating stall started with two emerging stall cells. The root cause of the variable stall cell count is unknown, but is not attributed to operating procedures.

  12. Potential use of the bioreactor to determine effects of microgravity and other environmental parameters on growth of hybridoma cells

    NASA Technical Reports Server (NTRS)

    Ley, Kenneth D.

    1987-01-01

    It is argued that the bioreactor being developed at NASA will allow researchers to determine the optimal conditions (e.g., pH, O sub 2, CO sub 2, nutrients) for growth of hybridoma cells, and to determine whether cell growth and antibody production are enhanced in the microgravity of space.

  13. Comparison of airfoil results from an adaptive wall test section and a porous wall test section

    NASA Technical Reports Server (NTRS)

    Mineck, Raymond E.

    1989-01-01

    Two wind tunnel investigations were conducted to assess two different wall interference alleviation/correction techniques: adaptive test section walls and classical analytical corrections. The same airfoil model has been tested in the adaptive wall test section of the NASA-Langley 0.3 m Transonic Cryogenic Tunnel (TCT) and in the National Aeronautical Establishment (NAE) High Reynolds Number 2-D facility. The model has a 9 in. chord and a CAST 10-2/DOA 2 airfoil section. The 0.3 m TCT adaptive wall test section has four solid walls with flexible top and bottom walls. The NAE test section has porous top and bottom walls and solid side walls. The aerodynamic results corrected for top and bottom wall interference at Mach numbers from 0.3 to 0.8 at a Reynolds number of 10 by 1,000,000. Movement of the adaptive walls was used to alleviate the top and bottom wall interference in the test results from the NASA tunnel.

  14. Rotational actuator of motor based on carbon nanotubes

    DOEpatents

    Zettl, Alexander K.; Fennimore, Adam M.; Yuzvinsky, Thomas D.

    2008-11-18

    A rotational actuator/motor based on rotation of a carbon nanotube is disclosed. The carbon nanotube is provided with a rotor plate attached to an outer wall, which moves relative to an inner wall of the nanotube. After deposit of a nanotube on a silicon chip substrate, the entire structure may be fabricated by lithography using selected techniques adapted from silicon manufacturing technology. The structures to be fabricated may comprise a multiwall carbon nanotube (MWNT), two in plane stators S1, S2 and a gate stator S3 buried beneath the substrate surface. The MWNT is suspended between two anchor pads and comprises a rotator attached to an outer wall and arranged to move in response to electromagnetic inputs. The substrate is etched away to allow the rotor to freely rotate. Rotation may be either in a reciprocal or fully rotatable manner.

  15. Rotational actuator or motor based on carbon nanotubes

    DOEpatents

    Zetti, Alexander K.; Fennimore, Adam M.; Yuzvinsky, Thomas D.

    2006-05-30

    A rotational actuator/motor based on rotation of a carbon nanotube is disclosed. The carbon nanotube is provided with a rotor plate attached to an outer wall, which moves relative to an inner wall of the nanotube. After deposit of a nanotube on a silicon chip substrate, the entire structure may be fabricated by lithography using selected techniques adapted from silicon manufacturing technology. The structures to be fabricated may comprise a multiwall carbon nanotube (MWNT), two in plane stators S1, S2 and a gate stator S3 buried beneath the substrate surface. The MWNT is suspended between two anchor pads and comprises a rotator attached to an outer wall and arranged to move in response to electromagnetic inputs. The substrate is etched away to allow the rotor to freely rotate. Rotation may be either in a reciprocal or fully rotatable manner.

  16. Heat transfer in rotating serpentine passages with selected model orientation for smooth or skewed trip walls

    NASA Technical Reports Server (NTRS)

    Johnson, B. V.; Wagner, J. H.; Steuber, G. D.; Yeh, F. C.

    1993-01-01

    Experiments were conducted to determine the effects of model orientation as well as buoyancy and Coriolis forces on heat transfer in turbine blade internal coolant passages. Turbine blades have internal coolant passage surfaces at the leading and trailing edges of the airfoil with surfaces at angles which are as large as +/- 50 to 60 degrees to the axis of rotation. Most of the previously-presented, multiple-passage, rotating heat transfer experiments have focused on radial passages aligned with the axis of rotation. Results from serpentine passages with orientations 0 and 45 degrees to the axis of rotation which simulate the coolant passages for the mid chord and trailing edge regions of the rotating airfoil are compared. The experiments were conducted with rotation in both directions to simulate serpentine coolant passages with the rearward flow of coolant or with the forward flow of coolant. The experiments were conducted for passages with smooth surfaces and with 45 degree trips adjacent to airfoil surfaces for the radial portion of the serpentine passages. At a typical flow condition, the heat transfer on the leading surfaces for flow outward in the first passage with smooth walls was twice as much for the model at 45 degrees compared to the model at 0 degrees. However, the differences for the other passages and with trips were less. In addition, the effects of buoyancy and Coriolis forces on heat transfer in the rotating passage were decreased with the model at 45 degrees, compared to the results at 0 degrees. The heat transfer in the turn regions and immediately downstream of the turns in the second passage with flow inward and in the third passage with flow outward was also a function of model orientation with differences as large as 40 to 50 percent occurring between the model orientations with forward flow and rearward flow of coolant.

  17. Microgravity

    NASA Image and Video Library

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  18. Impact of Bioreactor Environment and Recovery Method on the Profile of Bacterial Populations from Water Distribution Systems.

    PubMed

    Luo, Xia; Jellison, Kristen L; Huynh, Kevin; Widmer, Giovanni

    2015-01-01

    Multiple rotating annular reactors were seeded with biofilms flushed from water distribution systems to assess (1) whether biofilms grown in bioreactors are representative of biofilms flushed from the water distribution system in terms of bacterial composition and diversity, and (2) whether the biofilm sampling method affects the population profile of the attached bacterial community. Biofilms were grown in bioreactors until thickness stabilized (9 to 11 weeks) and harvested from reactor coupons by sonication, stomaching, bead-beating, and manual scraping. High-throughput sequencing of 16S rRNA amplicons was used to profile bacterial populations from flushed biofilms seeded into bioreactors as well as biofilms recovered from bioreactor coupons by different methods. β diversity between flushed and reactor biofilms was compared to β diversity between (i) biofilms harvested from different reactors and (ii) biofilms harvested by different methods from the same reactor. These analyses showed that average diversity between flushed and bioreactor biofilms was double the diversity between biofilms from different reactors operated in parallel. The diversity between bioreactors was larger than the diversity associated with different biofilm recovery methods. Compared to other experimental variables, the method used to recover biofilms had a negligible impact on the outcome of water biofilm analyses based on 16S amplicon sequencing. Results from this study show that biofilms grown in reactors over 9 to 11 weeks are not representative models of the microbial populations flushed from a distribution system. Furthermore, the bacterial population profile of biofilms grown in replicate reactors from the same flushed water are likely to diverge. However, four common sampling protocols, which differ with respect to disruption of bacterial cells, provide similar information with respect to the 16S rRNA population profile of the biofilm community.

  19. Bioreactor design for tendon/ligament engineering.

    PubMed

    Wang, Tao; Gardiner, Bruce S; Lin, Zhen; Rubenson, Jonas; Kirk, Thomas B; Wang, Allan; Xu, Jiake; Smith, David W; Lloyd, David G; Zheng, Ming H

    2013-04-01

    Tendon and ligament injury is a worldwide health problem, but the treatment options remain limited. Tendon and ligament engineering might provide an alternative tissue source for the surgical replacement of injured tendon. A bioreactor provides a controllable environment enabling the systematic study of specific biological, biochemical, and biomechanical requirements to design and manufacture engineered tendon/ligament tissue. Furthermore, the tendon/ligament bioreactor system can provide a suitable culture environment, which mimics the dynamics of the in vivo environment for tendon/ligament maturation. For clinical settings, bioreactors also have the advantages of less-contamination risk, high reproducibility of cell propagation by minimizing manual operation, and a consistent end product. In this review, we identify the key components, design preferences, and criteria that are required for the development of an ideal bioreactor for engineering tendons and ligaments.

  20. Design and Fabrication of Anatomical Bioreactor Systems Containing Alginate Scaffolds for Cartilage Tissue Engineering

    PubMed Central

    Gharravi, Anneh Mohammad; Orazizadeh, Mahmoud; Ansari-Asl, Karim; Banoni, Salem; Izadi, Sina; Hashemitabar, Mahmoud

    2012-01-01

    The aim of the present study was to develop a tissue-engineering approach through alginate gel molding to mimic cartilage tissue in a three-dimensional culture system. The perfusion biomimetic bioreactor was designed to mimic natural joint. The shear stresses exerting on the bioreactor chamber were calculated by Computational Fluid Dynamic (CFD). Several alginate/bovine chondrocyte constructs were prepared, and were cultured in the bioreactor. Histochemical and immunohistochemical staining methods for the presence of glycosaminoglycan(GAG), overall matrix production and type II collagen protein were performed, respectively. The dynamic mechanical device applied a linear mechanical displacement of 2 mm to 10 mm. The CFD modeling indicated peak velocity and maximum wall shear stress were 1.706×10−3 m/s and 0.02407 dyne/cm 2, respectively. Histochemical and immunohistochemical analysis revealed evidence of cartilage-like tissue with lacunas similar to those of natural cartilage and the production of sulfated GAG of matrix by the chondrons, metachromatic territorial matrix-surrounded cells and accumulation of type II collagen around the cells. The present study indicated that when chondrocytes were seeded in alginate hydrogel and cultured in biomimetic cell culture system, cells survived well and secreted newly synthesized matrix led to improvement of chondrogenesis. PMID:23408660

  1. Cell growth and differentiation on feeder layers is predicted to be influenced by bioreactor geometry.

    PubMed

    Peng, C A; Palsson, B Ø

    1996-06-05

    uniformity can be achieved for parameter values of P = 0.01, ..., 0.1 and Gz = 0.1, ..., 1.0. Among the four geometries investigated the radial-flow-type bioreactor provides the most uniform environment in which parenchymal cells can grow and differentiate ex vivo due to the absence of walls that are parallel to the flow paths creating slow flowing regions.

  2. A 3D analysis of oxygen transfer in a low-cost micro-bioreactor for animal cell suspension culture.

    PubMed

    Yu, P; Lee, T S; Zeng, Y; Low, H T

    2007-01-01

    A 3D numerical model was developed to study the flow field and oxygen transport in a micro-bioreactor with a rotating magnetic bar on the bottom to mix the culture medium. The Reynolds number (Re) was kept in the range of 100-716 to ensure laminar environment for animal cell culture. The volumetric oxygen transfer coefficient (k(L)a) was determined from the oxygen concentration distribution. It was found that the effect of the cell consumption on k(L)a could be negligible. A correlation was proposed to predict the liquid-phase oxygen transfer coefficient (k(Lm)) as a function of Re. The overall oxygen transfer coefficient (k(L)) was obtained by the two-resistance model. Another correlation, within an error of 15%, was proposed to estimate the minimum oxygen concentration to avoid cell hypoxia. By combination of the correlations, the maximum cell density, which the present micro-bioreactor could support, was predicted to be in the order of 10(12) cells m(-3). The results are comparable with typical values reported for animal cell growth in mechanically stirred bioreactors.

  3. Designing electrical stimulated bioreactors for nerve tissue engineering

    NASA Astrophysics Data System (ADS)

    Sagita, Ignasius Dwi; Whulanza, Yudan; Dhelika, Radon; Nurhadi, Ibrahim

    2018-02-01

    Bioreactor provides a biomimetic ecosystem that is able to culture cells in a physically controlled system. In general, the controlled-parameters are temperature, pH, fluid flow, nutrition flow, etc. In this study, we develop a bioreactor that specifically targeted to culture neural stem cells. This bioreactor could overcome some limitations of conventional culture technology, such as petri dish, by providing specific range of observation area and a uniform treatment. Moreover, the microfluidic bioreactor, which is a small-controlled environment, is able to observe as small number of cells as possible. A perfusion flow is applied to mimic the physiological environment in human body. Additionally, this bioreactor also provides an electrical stimulation which is needed by neural stem cells. In conclusion, we found the correlation between the induced shear stress with geometric parameters of the bioreactor. Ultimately, this system shall be used to observe the interaction between stimulation and cell growth.

  4. Wind tunnel wall interference

    NASA Technical Reports Server (NTRS)

    Newman, Perry A.; Mineck, Raymond E.; Barnwell, Richard W.; Kemp, William B., Jr.

    1986-01-01

    About a decade ago, interest in alleviating wind tunnel wall interference was renewed by advances in computational aerodynamics, concepts of adaptive test section walls, and plans for high Reynolds number transonic test facilities. Selection of NASA Langley cryogenic concept for the National Transonic Facility (NTF) tended to focus the renewed wall interference efforts. A brief overview and current status of some Langley sponsored transonic wind tunnel wall interference research are presented. Included are continuing efforts in basic wall flow studies, wall interference assessment/correction procedures, and adaptive wall technology.

  5. Design and evaluation of a bioreactor with application to forensic burial environments.

    PubMed

    Dunphy, Melissa A; Weisensee, Katherine E; Mikhailova, Elena A; Harman, Melinda K

    2015-12-01

    Existing forensic taphonomic methods lack specificity in estimating the postmortem interval (PMI) in the period following active decomposition. New methods, such as the use of citrate concentration in bone, are currently being considered; however, determining the applicability of these methods in differing environmental contexts is challenging. This research aims to design a forensic bioreactor that can account for environmental factors known to impact decomposition, specifically temperature, moisture, physical damage from animals, burial depth, soil pH, and organic matter content. These forensically relevant environmental variables were characterized in a soil science context. The resulting metrics were soil temperature regime, soil moisture regime, slope, texture, soil horizon, cation exchange capacity, soil pH, and organic matter content. Bioreactor chambers were constructed using sterilized thin-walled polystyrene boxes housed in calibrated temperature units. Gravesoil was represented using mineral soil (Ultisols), and organic soil proxy for Histosols, horticulture mix. Gravesoil depth was determined using mineral soil horizons A and Bt2 to simulate surface scatter and shallow grave burial respectively. A total of fourteen different environmental conditions were created and controlled successfully over a 90-day experiment. These results demonstrate successful implementation and control of forensic bioreactor simulating precise environments in a single research location, rather than site-specific testing occurring in different geographic regions. Bone sections were grossly assessed for weathering characteristics, which revealed notable differences related to exposure to different temperature regimes and soil types. Over the short 90-day duration of this experiment, changes in weathering characteristics were more evident across the different temperature regimes rather than the soil types. Using this methodology, bioreactor systems can be created to replicate many

  6. Rotational Fourier tracking of diffusing polygons.

    PubMed

    Mayoral, Kenny; Kennair, Terry P; Zhu, Xiaoming; Milazzo, James; Ngo, Kathy; Fryd, Michael M; Mason, Thomas G

    2011-11-01

    We use optical microscopy to measure the rotational Brownian motion of polygonal platelets that are dispersed in a liquid and confined by depletion attractions near a wall. The depletion attraction inhibits out-of-plane translational and rotational Brownian fluctuations, thereby facilitating in-plane imaging and video analysis. By taking fast Fourier transforms (FFTs) of the images and analyzing the angular position of rays in the FFTs, we determine an isolated particle's rotational trajectory, independent of its position. The measured in-plane rotational diffusion coefficients are significantly smaller than estimates for the bulk; this difference is likely due to the close proximity of the particles to the wall arising from the depletion attraction.

  7. Bioreactor Design for Tendon/Ligament Engineering

    PubMed Central

    Wang, Tao; Gardiner, Bruce S.; Lin, Zhen; Rubenson, Jonas; Kirk, Thomas B.; Wang, Allan; Xu, Jiake

    2013-01-01

    Tendon and ligament injury is a worldwide health problem, but the treatment options remain limited. Tendon and ligament engineering might provide an alternative tissue source for the surgical replacement of injured tendon. A bioreactor provides a controllable environment enabling the systematic study of specific biological, biochemical, and biomechanical requirements to design and manufacture engineered tendon/ligament tissue. Furthermore, the tendon/ligament bioreactor system can provide a suitable culture environment, which mimics the dynamics of the in vivo environment for tendon/ligament maturation. For clinical settings, bioreactors also have the advantages of less-contamination risk, high reproducibility of cell propagation by minimizing manual operation, and a consistent end product. In this review, we identify the key components, design preferences, and criteria that are required for the development of an ideal bioreactor for engineering tendons and ligaments. PMID:23072472

  8. Phase separated membrane bioreactor: Results from model system studies

    NASA Astrophysics Data System (ADS)

    Petersen, G. R.; Seshan, P. K.; Dunlop, E. H.

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestial simulation.

  9. Phase separated membrane bioreactor - Results from model system studies

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.; Seshan, P. K.; Dunlop, E. H.

    1989-01-01

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestrial simulation.

  10. Model system studies with a phase separated membrane bioreactor

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.; Seshan, P. K.; Dunlop, Eric H.

    1989-01-01

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestial simulation.

  11. Schisandra lignans production regulated by different bioreactor type.

    PubMed

    Szopa, Agnieszka; Kokotkiewicz, Adam; Luczkiewicz, Maria; Ekiert, Halina

    2017-04-10

    Schisandra chinensis (Chinese magnolia vine) is a rich source of therapeutically relevant dibenzocyclooctadiene lignans with anticancer, immunostimulant and hepatoprotective activities. In this work, shoot cultures of S. chinensis were grown in different types of bioreactors with the aim to select a system suitable for the large scale in vitro production of schisandra lignans. The cultures were maintained in Murashige-Skoog (MS) medium supplemented with 3mg/l 6-benzylaminopurine (BA) and 1mg/l 1-naphthaleneacetic acid (NAA). Five bioreactors differing with respect to cultivation mode were tested: two liquid-phase systems (baloon-type bioreactor and bubble-column bioreactor with biomass immobilization), the gas-phase spray bioreactor and two commercially available temporary immersion systems: RITA ® and Plantform. The experiments were run for 30 and 60 days in batch mode. The harvested shoots were evaluated for growth and lignan content determined by LC-DAD and LC-DAD-ESI-MS. Of the tested bioreactors, temporary immersion systems provided the best results with respect to biomass production and lignan accumulation: RITA ® bioreactor yielded 17.86g/l (dry weight) during 60 day growth period whereas shoots grown for 30 days in Plantform bioreactor contained the highest amount of lignans (546.98mg/100g dry weight), with schisandrin, deoxyschisandrin and gomisin A as the major constituents (118.59, 77.66 and 67.86mg/100g dry weight, respectively). Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Miniature rotating transmissive optical drum scanner

    NASA Technical Reports Server (NTRS)

    Lewis, Robert (Inventor); Parrington, Lawrence (Inventor); Rutberg, Michael (Inventor)

    2013-01-01

    A miniature rotating transmissive optical scanner system employs a drum of small size having an interior defined by a circumferential wall rotatable on a drum axis, an optical element positioned within the interior of the drum, and a light-transmissive lens aperture provided at an angular position in the circumferential wall of the drum for scanning a light beam to or from the optical element in the drum along a beam azimuth angle as the drum is rotated. The miniature optical drum scanner configuration obtains a wide scanning field-of-view (FOV) and large effective aperture is achieved within a physically small size.

  13. Wall interaction effects for a full-scale helicopter rotor in the NASA Ames 80- by 120-foot wind tunnel

    NASA Technical Reports Server (NTRS)

    Shinoda, Patrick M.

    1994-01-01

    A full-scale helicopter rotor test was conducted in the NASA Ames 80- by 120-Foot Wind Tunnel with a four-bladed S-76 rotor system. This wind tunnel test generated a unique and extensive data base covering a wide range of rotor shaft angles-of-attack and rotor thrust conditions from 0 to 100 knots. Three configurations were tested: (1) empty tunnel; (2) test stand body (fuselage) and support system; and (3) fuselage and support system with rotor installed. Empty tunnel wall pressure data are evaluated as a function of tunnel speed to understand the baseline characteristics. Aerodynamic interaction effects between the fuselage and the walls of the tunnel are investigated by comparing wall, ceiling, and floor pressures for various tunnel velocities and fuselage angles-of-attack. Aerodynamic interaction effects between the rotor and the walls of the tunnel are also investigated by comparing wall, ceiling, and floor pressures for various rotor shaft angles, rotor thrust conditions, and tunnel velocities. Empty tunnel wall pressure data show good repeatability and are not affected by tunnel speed. In addition, the tunnel wall pressure profiles are not affected by the presence of the fuselage apart from a pressure shift. Results do not indicate that the tunnel wall pressure profiles are affected by the presence of the rotor. Significant changes in the wall, ceiling, and floor pressure profiles occur with changing tunnel speeds for constant rotor thrust and shaft angle conditions. Significant changes were also observed when varying rotor thrust or rotor shaft angle-of-attack. Other results indicate that dynamic rotor loads and blade motion are influenced by the presence of the tunnel walls at very low tunnel velocity and, together with the wall pressure data, provide a good indication of flow breakdown.

  14. CFD of mixing of multi-phase flow in a bioreactor using population balance model.

    PubMed

    Sarkar, Jayati; Shekhawat, Lalita Kanwar; Loomba, Varun; Rathore, Anurag S

    2016-05-01

    Mixing in bioreactors is known to be crucial for achieving efficient mass and heat transfer, both of which thereby impact not only growth of cells but also product quality. In a typical bioreactor, the rate of transport of oxygen from air is the limiting factor. While higher impeller speeds can enhance mixing, they can also cause severe cell damage. Hence, it is crucial to understand the hydrodynamics in a bioreactor to achieve optimal performance. This article presents a novel approach involving use of computational fluid dynamics (CFD) to model the hydrodynamics of an aerated stirred bioreactor for production of a monoclonal antibody therapeutic via mammalian cell culture. This is achieved by estimating the volume averaged mass transfer coefficient (kL a) under varying conditions of the process parameters. The process parameters that have been examined include the impeller rotational speed and the flow rate of the incoming gas through the sparger inlet. To undermine the two-phase flow and turbulence, an Eulerian-Eulerian multiphase model and k-ε turbulence model have been used, respectively. These have further been coupled with population balance model to incorporate the various interphase interactions that lead to coalescence and breakage of bubbles. We have successfully demonstrated the utility of CFD as a tool to predict size distribution of bubbles as a function of process parameters and an efficient approach for obtaining optimized mixing conditions in the reactor. The proposed approach is significantly time and resource efficient when compared to the hit and trial, all experimental approach that is presently used. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:613-628, 2016. © 2016 American Institute of Chemical Engineers.

  15. Two-liquid-phase bioreactors.

    PubMed

    Van Sonsbeek, H M; Beeftink, H H; Tramper, J

    1993-09-01

    The application of two liquid phases that are poorly miscible is a fascinating research topic for biocatalytical conversions because of the promising results. Motives for application include an increase of productivity and achievement of continuous processing, but new limitations arise, e.g., interfacial effects such as biocatalyst accumulation and loss of activity, medium component accumulation, and slow coalescence. Centrifuges, membranes, and immobilization are tools that can overcome part of the problems, but more fundamental knowledge about interfaces and coalescence is still necessary for successful application. For scaleup and further development of processes based on the obtained results, a choice must be made for the configuration of the experimental setup of a bioreactor. Aspects like aeration, shear stress, batch or continuous processing, and immobilization can play an important role. This review article describes these aspects and the proposals that have been made in recent years concerning two-liquid-phase bioreactors. It shows some adaptations to existing bioreactors, such as loop reactors and stirred-tank reactors.

  16. EVALUATION PLAN FOR TWO LARGE-SCALE LANDFILL BIOREACTOR TECHNOLOGIES

    EPA Science Inventory

    Abstract - Waste Management, Inc., is operating two long-term bioreactor studies at the Outer Loop Landfill in Louisville, KY, including facultative landfill bioreactor and staged aerobic-anaerobic landfill bioreactor demonstrations. A Quality Assurance Project Plan (QAPP) was p...

  17. Role of Bioreactors in Microbial Biomass and Energy Conversion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Liang; Zhang, Biao; Zhu, Xun

    Bioenergy is the world’s largest contributor to the renewable and sustainable energy sector, and it plays a significant role in various energy industries. A large amount of research has contributed to the rapidly evolving field of bioenergy and one of the most important topics is the use of the bioreactor. Bioreactors play a critical role in the successful development of technologies for microbial biomass cultivation and energy conversion. In this chapter, after a brief introduction to bioreactors (basic concepts, configurations, functions, and influencing factors), the applications of the bioreactor in microbial biomass, microbial biofuel conversion, and microbial electrochemical systems aremore » described. Importantly, the role and significance of the bioreactor in the bioenergy process are discussed to provide a better understanding of the use of bioreactors in managing microbial biomass and energy conversion.« less

  18. Reynolds-Stress and Triple-Product Models Applied to a Flow with Rotation and Curvature

    NASA Technical Reports Server (NTRS)

    Olsen, Michael E.

    2016-01-01

    Turbulence models, with increasing complexity, up to triple product terms, are applied to the flow in a rotating pipe. The rotating pipe is a challenging case for turbulence models as it contains significant rotational and curvature effects. The flow field starts with the classic fully developed pipe flow, with a stationary pipe wall. This well defined condition is then subjected to a section of pipe with a rotating wall. The rotating wall introduces a second velocity scale, and creates Reynolds shear stresses in the radial-circumferential and circumferential-axial planes. Furthermore, the wall rotation introduces a flow stabilization, and actually reduces the turbulent kinetic energy as the flow moves along the rotating wall section. It is shown in the present work that the Reynolds stress models are capable of predicting significant reduction in the turbulent kinetic energy, but triple product improves the predictions of the centerline turbulent kinetic energy, which is governed by convection, dissipation and transport terms, as the production terms vanish on the pipe axis.

  19. Multifunctional Bioreactor System for Human Intestine Tissues

    PubMed Central

    2017-01-01

    The three-dimensional (3D) cultivation of intestinal cells and tissues in dynamic bioreactor systems to represent in vivo intestinal microenvironments is essential for developing regenerative medicine treatments for intestinal diseases. We have previously developed in vitro human intestinal tissue systems using a 3D porous silk scaffold system with intestinal architectures and topographical features for the adhesion, growth, and differentiation of intestinal cells under static culture conditions. In this study, we designed and fabricated a multifunctional bioreactor system that incorporates pre-epithelialized 3D silk scaffolds in a dynamic culture environment for in vitro engineering of human intestine tissues. The bioreactor system allows for control of oxygen levels in perfusion fluids (aerobic simulated intestinal fluid (SIF), microaerobic SIF, and anaerobic SIF), while ensuring control over the mechanical and chemical microenvironments present in native human intestines. The bioreactor system also enables 3D cell culture with spatial separation and cultivation of cocultured epithelial and stromal cells. Preliminary functional analysis of tissues housed in the bioreactor demonstrated that the 3D tissue constructs survived and maintained typical phenotypes of intestinal epithelium, including epithelial tight junction formation, intestinal biomarker expression, microvilli formation, and mucus secretion. The unique combination of a dynamic bioreactor and 3D intestinal constructs offers utility for engineering human intestinal tissues for the study of intestinal diseases and discovery options for new treatments. PMID:29333491

  20. In Situ Bioreactor

    ScienceCinema

    Blackwelder, Brad

    2018-05-11

    At Idaho National Laboratory, researchers have developed bioreactor technology that permits identification, bioremediation testing and treatment at the source using naturally occurring microbes to disarm contaminants.

  1. Bioreactor Technology in Cardiovascular Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Mertsching, H.; Hansmann, J.

    Cardiovascular tissue engineering is a fast evolving field of biomedical science and technology to manufacture viable blood vessels, heart valves, myocar-dial substitutes and vascularised complex tissues. In consideration of the specific role of the haemodynamics of human circulation, bioreactors are a fundamental of this field. The development of perfusion bioreactor technology is a consequence of successes in extracorporeal circulation techniques, to provide an in vitro environment mimicking in vivo conditions. The bioreactor system should enable an automatic hydrodynamic regime control. Furthermore, the systematic studies regarding the cellular responses to various mechanical and biochemical cues guarantee the viability, bio-monitoring, testing, storage and transportation of the growing tissue.

  2. Effect of sudden addition of PCE and bioreactor coupling to ZVI filters on performance of fluidized bed bioreactors operated in simultaneous electron acceptor modes.

    PubMed

    Moreno-Medina, C U; Poggi-Varaldo, Hector M; Breton-Deval, L; Rinderknecht-Seijas, N

    2017-11-01

    The present work evaluated the effects of (i) feeding a water contaminated with 80 mg/L PCE to bioreactors seeded with inoculum not acclimated to PCE, (ii) coupling ZVI side filters to bioreactors, and (iii) working in different biological regimes, i.e., simultaneous methanogenic aeration and simultaneous methanogenic-denitrifying regimes, on fluidized bed bioreactor performance. Simultaneous electron acceptors refer to the simultaneous presence of two compounds operating as final electron acceptors in the biological respiratory chain (e.g., use of either O 2 or NO 3 - in combination with a methanogenic environment) in a bioreactor or environmental niche. Four lab-scale, mesophilic, fluidized bed bioreactors (bioreactors) were implemented. Two bioreactors were operated as simultaneous methanogenic-denitrifying (MD) units, whereas the other two were operated in partially aerated methanogenic (PAM) mode. In the first period, all bioreactors received a wastewater with 1 g chemical oxygen demand of methanol per liter (COD-methanol/L). In a second period, all the bioreactors received the wastewater plus 80 mg perchloroethylene (PCE)/L; at the start of period 2, one MD and one PAM were coupled to side sand-zero valent iron filters (ZVI). All bioreactors were inoculated with a microbial consortium not acclimated to PCE. In this work, the performance of the full period 1 and the first 60 days of period 2 is reported and discussed. The COD removal efficiency and the nitrate removal efficiency of the bioreactors essentially did not change between period 1 and period 2, i.e., upon PCE addition. On the contrary, specific methanogenic activity in PAM bioreactors (both with and without coupled ZVI filter) significantly decreased. This was consistent with a sharp fall of methane productivity in those bioreactors in period 2. During period 2, PCE removals in the range 86 to 97 % were generally observed; the highest removal corresponded to PAM bioreactors along with the

  3. Effects of rotation on coolant passage heat transfer. Volume 2: Coolant passages with trips normal and skewed to the flow

    NASA Technical Reports Server (NTRS)

    Johnson, B. V.; Wagner, J. H.; Steuber, G. D.

    1993-01-01

    An experimental program was conducted to investigate heat transfer and pressure loss characteristics of rotating multipass passages, for configurations and dimensions typical of modem turbine blades. This experimental program is one part of the NASA Hot Section Technology (HOST) Initiative, which has as its overall objective the development and verification of improved analysis methods that will form the basis for a design system that will produce turbine components with improved durability. The objective of this program was the generation of a data base of heat transfer and pressure loss data required to develop heat transfer correlations and to assess computational fluid dynamic techniques for rotating coolant passages. The experimental work was broken down into two phases. Phase 1 consists of experiments conducted in a smooth wall large scale heat transfer model. A detailed discussion of these results was presented in volume 1 of a NASA Report. In Phase 2 the large scale model was modified to investigate the effects of skewed and normal passage turbulators. The results of Phase 2 along with comparison to Phase 1 is the subject of this Volume 2 NASA Report.

  4. Denitrifying bioreactor clogging potential during wastewater treatment.

    PubMed

    Christianson, Laura E; Lepine, Christine; Sharrer, Kata L; Summerfelt, Steven T

    2016-11-15

    Chemoheterotrophic denitrification technologies using woodchips as a solid carbon source (i.e., woodchip bioreactors) have been widely trialed for treatment of diffuse-source agricultural nitrogen pollution. There is growing interest in the use of this simple, relatively low-cost biological wastewater treatment option in waters with relatively higher total suspended solids (TSS) and chemical oxygen demand (COD) such as aquaculture wastewater. This work: (1) evaluated hydraulic retention time (HRT) impacts on COD/TSS removal, and (2) assessed the potential for woodchip clogging under this wastewater chemistry. Four pilot-scale woodchip denitrification bioreactors operated for 267 d showed excellent TSS removal (>90%) which occurred primarily near the inlet, and that COD removal was maximized at lower HRTs (e.g., 56% removal efficiency and 25 g of COD removed per m 3 of bioreactor per d at a 24 h HRT). However, influent wastewater took progressively longer to move into the woodchips likely due to a combination of (1) woodchip settling, (2) clogging due to removed wastewater solids and/or accumulated bacterial growth, and (3) the pulsed flow system pushing the chips away from the inlet. The bioreactor that received the highest loading rate experienced the most altered hydraulics. Statistically significant increases in woodchip P content over time in woodchip bags placed near the bioreactor outlets (0.03 vs 0.10%P 2 O 5 ) and along the bioreactor floor (0.04 vs. 0.12%P 2 O 5 ) confirmed wastewater solids were being removed and may pose a concern for subsequent nutrient mineralization and release. Nevertheless, the excellent nitrate-nitrogen and TSS removal along with notable COD removal indicated woodchip bioreactors are a viable water treatment technology for these types of wastewaters given they are used downstream of a filtration device. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Ab initio study of edge effect on relative motion of walls in carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Popov, Andrey M.; Lebedeva, Irina V.; Knizhnik, Andrey A.; Lozovik, Yurii E.; Potapkin, Boris V.

    2013-01-01

    Interwall interaction energies of double-walled nanotubes with long inner and short outer walls are calculated as functions of coordinates describing relative rotation and displacement of the walls using van der Waals corrected density functional theory. The magnitude of corrugation and the shape of the potential energy relief are found to be very sensitive to changes of the shorter wall length at subnanometer scale and atomic structure of the edges if at least one of the walls is chiral. Threshold forces required to start relative motion of the short walls and temperatures at which the transition between diffusive and free motion of the short walls takes place are estimated. The edges are also shown to provide a considerable contribution to the barrier to relative rotation of commensurate nonchiral walls. For such walls, temperatures of orientational melting, i.e., the crossover from rotational diffusion to free relative rotation, are estimated. The possibility to produce nanotube-based bolt/nut pairs and nanobearings is discussed.

  6. Development of Fundamental Technologies for Micro Bioreactors

    NASA Astrophysics Data System (ADS)

    Sato, Kiichi; Kitamori, Takehiko

    This chapter reviews the development of fundamental technologies required for microchip-based bioreactors utilizing living mammalian cells and pressure driven flow. The most important factor in the bioreactor is the cell culture. For proper cell culturing, continuous medium supply from a microfluidic channel and appropriate modification of the channel surface to accommodate cell attachment is required. Moreover, the medium flow rate should be chosen carefully, because shear stress affects cell activity. The techniques presented here could be applied to the development of micro bioreactors such as microlivers, pigment production by plant cells, and artificial insemination.

  7. Design and testing of a unique randomized gravity, continuous flow bioreactor

    NASA Technical Reports Server (NTRS)

    Lassiter, Carroll B.

    1993-01-01

    A rotating, null gravity simulator, or Couette bioreactor was successfully used for the culture of mammalian cells in a simulated microgravity environment. Two limited studies using Lipomyces starkeyi and Streptomyces clavuligerus were also conducted under conditions of simulated weightlessness. Although these studies with microorganisms showed promising preliminary results, oxygen limitations presented significant limitations in studying the biochemical and cultural characteristics of these cell types. Microbial cell systems such as bacteria and yeast promise significant potential as investigative models to study the effects of microgravity on membrane transport, as well as substrate induction of inactive enzyme systems. Additionally, the smaller size of the microorganisms should further reduce the gravity induced oscillatory particle motion and thereby improve the microgravity simulation on earth. Focus is on the unique conceptual design, and subsequent development of a rotating bioreactor that is compatible with the culture and investigation of microgravity effects on microbial systems. The new reactor design will allow testing of highly aerobic cell types under simulated microgravity conditions. The described reactor affords a mechanism for investigating the long term effects of reduced gravity on cellular respiration, membrane transfer, ion exchange, and substrate conversions. It offers the capability of dynamically altering nutrients, oxygenation, pH, carbon dioxide, and substrate concentration without disturbing the microgravity simulation, or Couette flow, of the reactor. All progeny of the original cell inoculum may be acclimated to the simulated microgravity in the absence of a substrate or nutrient. The reactor has the promise of allowing scientists to probe the long term effects of weightlessness on cell interactions in plants, bacteria, yeast, and fungi. The reactor is designed to have a flow field growth chamber with uniform shear stress, yet transfer

  8. Co-Production of Fungal Biomass Derived Constituents and Ethanol from Citrus Wastes Free Sugars without Auxiliary Nutrients in Airlift Bioreactor.

    PubMed

    Satari, Behzad; Karimi, Keikhosro; Taherzadeh, Mohammad J; Zamani, Akram

    2016-02-26

    The potential of two zygomycetes fungi, Mucor indicus and Rhizopus oryzae, in assimilating citrus waste free sugars (CWFS) and producing fungal chitosan, oil, and protein as well as ethanol was investigated. Extraction of free sugars from citrus waste can reduce its environmental impact by decreasing the possibility of wild microorganisms growth and formation of bad odors, a typical problem facing the citrus industries. A total sugar concentration of 25.1 g/L was obtained by water extraction of citrus waste at room temperature, used for fungal cultivation in shake flasks and airlift bioreactor with no additional nutrients. In shake flasks cultivations, the fungi were only able to assimilate glucose, while fructose remained almost intact. In contrast, the cultivation of M. indicus and R. oryzae in the four-liter airlift bioreactor resulted in the consumption of almost all sugars and production of 250 and 280 g fungal biomass per kg of consumed sugar, respectively. These biomasses correspondingly contained 40% and 51% protein and 9.8% and 4.4% oil. Furthermore, the fungal cell walls, obtained after removing the alkali soluble fraction of the fungi, contained 0.61 and 0.69 g chitin and chitosan per g of cell wall for M. indicus and R. oryzae, respectively. Moreover, the maximum ethanol yield of 36% and 18% was obtained from M. indicus and R. oryzae, respectively. Furthermore, that M. indicus grew as clump mycelia in the airlift bioreactor, while R. oryzae formed spherical suspended pellets, is a promising feature towards industrialization of the process.

  9. Co-Production of Fungal Biomass Derived Constituents and Ethanol from Citrus Wastes Free Sugars without Auxiliary Nutrients in Airlift Bioreactor

    PubMed Central

    Satari, Behzad; Karimi, Keikhosro; Taherzadeh, Mohammad J.; Zamani, Akram

    2016-01-01

    The potential of two zygomycetes fungi, Mucor indicus and Rhizopus oryzae, in assimilating citrus waste free sugars (CWFS) and producing fungal chitosan, oil, and protein as well as ethanol was investigated. Extraction of free sugars from citrus waste can reduce its environmental impact by decreasing the possibility of wild microorganisms growth and formation of bad odors, a typical problem facing the citrus industries. A total sugar concentration of 25.1 g/L was obtained by water extraction of citrus waste at room temperature, used for fungal cultivation in shake flasks and airlift bioreactor with no additional nutrients. In shake flasks cultivations, the fungi were only able to assimilate glucose, while fructose remained almost intact. In contrast, the cultivation of M. indicus and R. oryzae in the four-liter airlift bioreactor resulted in the consumption of almost all sugars and production of 250 and 280 g fungal biomass per kg of consumed sugar, respectively. These biomasses correspondingly contained 40% and 51% protein and 9.8% and 4.4% oil. Furthermore, the fungal cell walls, obtained after removing the alkali soluble fraction of the fungi, contained 0.61 and 0.69 g chitin and chitosan per g of cell wall for M. indicus and R. oryzae, respectively. Moreover, the maximum ethanol yield of 36% and 18% was obtained from M. indicus and R. oryzae, respectively. Furthermore, that M. indicus grew as clump mycelia in the airlift bioreactor, while R. oryzae formed spherical suspended pellets, is a promising feature towards industrialization of the process. PMID:26927089

  10. BIOREACTOR DESIGN - OUTER LOOP LANDFILL, LOUISVILLE, KY

    EPA Science Inventory

    Bioreactor field demonstration projects are underway at the Outer Loop Landfill in Louisville, KY, USA. The research effort is a cooperative research effort between US EPA and Waste Management Inc. Two primary kinds of municipal waste bioreactors are under study at this site. ...

  11. BIOREACTOR LANDFILLS, THEORETICAL ADVANTAGES AND RESEARCH CHALLENGES

    EPA Science Inventory

    Bioreactor landfills are municipal solid waste landfills that utilize bulk liquids in an effort to accelerate solid waste degradation. There are few potential benefits for operating a MSW landfill as a bioreactor. These include leachate treatment and management, increase in the s...

  12. Membrane Bioreactor With Pressure Cycle

    NASA Technical Reports Server (NTRS)

    Efthymiou, George S.; Shuler, Michael L.

    1991-01-01

    Improved class of multilayer membrane bioreactors uses convention forced by differences in pressure to overcome some of diffusional limitations of prior bioreactors. In reactor of new class, flow of nutrient solution reduces adverse gradients of concentration, keeps cells supplied with fresh nutrient, and sweeps away products faster than diffusion alone. As result, overall yield and rate of reaction increased. Pressures in sweeping gas and nutrient alternated to force nutrient liquid into and out of biocatalyst layer through hyrophilic membrane.

  13. Intermittent nature of acceleration in near wall turbulence.

    PubMed

    Lee, Changhoon; Yeo, Kyongmin; Choi, Jung-Il

    2004-04-09

    Using direct numerical simulation of a fully developed turbulent channel flow, we investigate the behavior of acceleration near a solid wall. We find that acceleration near the wall is highly intermittent and the intermittency is in large part associated with the near wall organized coherent turbulence structures. We also find that acceleration of large magnitude is mostly directed towards the rotation axis of the coherent vortical structures, indicating that the source of the intermittent acceleration is the rotational motion associated with the vortices that causes centripetal acceleration.

  14. Hydrofocusing Bioreactor for Three-Dimensional Cell Culture

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R.; Spaulding, Glenn F.; Tsao, Yow-Min D.; Flechsig, Scott; Jones, Leslie; Soehnge, Holly

    2003-01-01

    The hydrodynamic focusing bioreactor (HFB) is a bioreactor system designed for three-dimensional cell culture and tissue-engineering investigations on orbiting spacecraft and in laboratories on Earth. The HFB offers a unique hydrofocusing capability that enables the creation of a low-shear culture environment simultaneously with the "herding" of suspended cells, tissue assemblies, and air bubbles. Under development for use in the Biotechnology Facility on the International Space Station, the HFB has successfully grown large three-dimensional, tissuelike assemblies from anchorage-dependent cells and grown suspension hybridoma cells to high densities. The HFB, based on the principle of hydrodynamic focusing, provides the capability to control the movement of air bubbles and removes them from the bioreactor without degrading the low-shear culture environment or the suspended three-dimensional tissue assemblies. The HFB also provides unparalleled control over the locations of cells and tissues within its bioreactor vessel during operation and sampling.

  15. Atmospheric Rotational Effects on Mars Based on the NASA Ames General Circulation Model: Angular Momentum Approach

    NASA Technical Reports Server (NTRS)

    Sanchez, Braulio V.; Haberle, Robert M.; Schaeffer, James

    2004-01-01

    The objective of the investigation is to determine the motion of the rotational axis of Mars as a result of mass variations in the atmosphere and condensation and sublimation of CO2 ice on the polar caps. A planet experiences this type of motion if it has an atmosphere, which is changing its mass distribution with respect to the solid body of the planet and/or it is asymmetrically changing the amount of ice at the polar caps. The physical principle involved is the conservation of angular momentum, one can get a feeling for it by sitting on a well oiled swivel chair holding a rotating wheel on a horizontal direction and then changing the rotation axis of the wheel to a vertical direction. The person holding the wheel and the chair would begin to rotate in opposite direction to the rotation of the wheel. The motions of Mars atmosphere and the ice caps variations are obtained from a mathematical model developed at the NASA Ames Research Center. The model produces outputs for a time span of one Martian year, which is equivalent to 687 Earth days. The results indicate that Mars axis of rotation moves in a spiral with respect to a reference point on the surface of the planet. It can move as far away as 35.3 cm from the initial location as a result of both mass variations in the atmosphere and asymmetric ice variations at the polar caps. Furthermore the pole performs close to two revolutions around the reference point during a Martian year. This motion is a combination of two motions, one produced by the atmospheric mass variations and another due to the variations in the ice caps. The motion due to the atmospheric variations is a spiral performing about two and a half revolutions around the reference point during which the pole can move as far as 40.9 cm. The motion due to variations in the ice caps is a spiral performing almost three revolutions during which the pole can move as far as 32.8 cm.

  16. Antagonistic role of vertebral translation against vertebral rotation in the spontaneous postoperative modulation of the anterior chest wall contour in thoracic idiopathic scoliosis.

    PubMed

    Qian, Bang-ping; Mao, Sai-hu; Zhu, Ze-zhang; Zhu, Feng; Liu, Zhen; Xu, Lei-lei; Wang, Bing; Yu, Yang; Qiu, Yong

    2013-09-01

    A computed tomography study. To identify the best scoliotic deformity components that show impact upon the spontaneous postoperative modulation of the deformed anterior chest wall contour in right convex thoracic adolescent idiopathic scoliosis. Spontaneous postoperative aggravation of the anterior concave costal projection was a common occurrence in adolescent idiopathic scoliosis, yet the risk factors that effectively bridged the gap between what the surgeons did in the interior and how the rib cages reacted on the exterior were still open to debate. Pre- and postoperative computed tomographic scans of 77 patients with right convex thoracic adolescent idiopathic scoliosis were retrieved and analyzed. According to the postoperative variation of anterior chest wall angle (CWA), the patients were divided into 2 groups with either aggravated or improved CWA. Multiple scoliotic deformity parameters and their surgical correction rates were evaluated, correlated, and then compared between the 2 groups. Moreover, patients with apex located at T9 were isolated and evaluated independently. A logistic regression analysis was used to determine the independent predictors of the spontaneous postoperative modulation of the anterior chest wall contour. The surgical correction rate of Cobb angle (supine), the rotational angle with respect to the sagittal plane (RAsag angle), the rotational angle with respect to the anterior midline of the body (RAml angle), the angle of lateral deviation of the apical vertebrae from the midline (MLdev angle), the posterior hemithorax ratio, the vertebral translation (VT), and the thoracic rotation averaged 64.6%, 19.5%, 30.8%, 39.2%, 15.0%, 41.2%, and 28.7%, respectively. Ratio of aggravated anterior chest wall contour was the highest at the T7 apex group (84.6%) as compared with T8 apex group (47.1%), T9 apex group (19.5%), and T10 apex group (0.0%). The preoperative CWA was significantly lower in the aggravated CWA group when compared with the

  17. Shaping effects on toroidal magnetohydrodynamic modes in the presence of plasma and wall resistivity

    NASA Astrophysics Data System (ADS)

    Rhodes, Dov J.; Cole, A. J.; Brennan, D. P.; Finn, J. M.; Li, M.; Fitzpatrick, R.; Mauel, M. E.; Navratil, G. A.

    2018-01-01

    This study explores the effects of plasma shaping on magnetohydrodynamic mode stability and rotational stabilization in a tokamak, including both plasma and wall resistivity. Depending upon the plasma shape, safety factor, and distance from the wall, the β-limit for rotational stabilization is given by either the resistive-plasma ideal-wall (tearing mode) limit or the ideal-plasma resistive-wall (resistive wall mode) limit. In order to explore this broad parameter space, a sharp-boundary model is developed with a realistic geometry, resonant tearing surfaces, and a resistive wall. The β-limit achievable in the presence of stabilization by rigid plasma rotation, or by an equivalent feedback control with imaginary normal-field gain, is shown to peak at specific values of elongation and triangularity. It is shown that the optimal shaping with rotation typically coincides with transitions between tearing-dominated and wall-dominated mode behavior.

  18. Bioreactor technology for production of valuable algal products

    NASA Astrophysics Data System (ADS)

    Liu, Guo-Cai; Cao, Ying

    1998-03-01

    Bioreactor technology has long been employed for the production of various (mostly cheap) food and pharmaceutical products. More recently, research has been mainly focused on the development of novel bioreactor technology for the production of high—value products. This paper reports the employment of novel bioreactor technology for the production of high-value biomass and metabolites by microalgae. These high-value products include microalgal biomass as health foods, pigments including phycocyanin and carotenoids, and polyunsaturated fatty acids such as eicosapentaenoic acid and docosahexaenoic acid. The processes involved include heterotrophic and mixotrophic cultures using organic substrates as the carbon source. We have demonstrated that these bioreactor cultivation systems are particularly suitable for the production of high-value products from various microalgae. These cultivation systems can be further modified to improve cell densities and productivities by using high cell density techniques such as fed-batch and membrane cell recycle systems. For most of the microalgae investigated, the maximum cell concentrations obtained using these bioreactor systems in our laboratories are much higher than any so far reported in the literature.

  19. BIOREACTOR LANDFILL DESIGN

    EPA Science Inventory

    Modern landfill design entails many elements including foundations, liner systems, leachate collection systems, stormwater control systems, slope stability considerations, leachate management systems, gas extraction systems, and capping and closure. The use of bioreactor technolo...

  20. Rotating field mass and velocity analyzer

    NASA Technical Reports Server (NTRS)

    Smith, Steven Joel (Inventor); Chutjian, Ara (Inventor)

    1998-01-01

    A rotating field mass and velocity analyzer having a cell with four walls, time dependent RF potentials that are applied to each wall, and a detector. The time dependent RF potentials create an RF field in the cell which effectively rotates within the cell. An ion beam is accelerated into the cell and the rotating RF field disperses the incident ion beam according to the mass-to-charge (m/e) ratio and velocity distribution present in the ion beam. The ions of the beam either collide with the ion detector or deflect away from the ion detector, depending on the m/e, RF amplitude, and RF frequency. The detector counts the incident ions to determine the m/e and velocity distribution in the ion beam.

  1. Feasibility of vibration monitoring of small rotating machines for the environmental control and life support systems (ECLSS) of the NASA advanced space craft

    NASA Technical Reports Server (NTRS)

    Milner, G. Martin; Black, Mike; Hovenga, Mike; Mcclure, Paul; Miller, Patrice

    1988-01-01

    The application of vibration monitoring to the rotating machinery typical of ECLSS components in advanced NASA spacecraft was studied. It is found that the weighted summation of the accelerometer power spectrum is the most successful detection scheme for a majority of problem types. Other detection schemes studied included high-frequency demodulation, cepstrum, clustering, and amplitude processing.

  2. A Novel Designed Bioreactor for Recovering Precious Metals from Waste Printed Circuit Boards

    PubMed Central

    Jujun, Ruan; Jie, Zheng; Jian, Hu; Zhang, Jianwen

    2015-01-01

    For recovering precious metals from waste printed circuit boards (PCBs), a novel hybrid technology including physical and biological methods was developed. It consisted of crushing, corona-electrostatic separation, and bioleaching. Bioleaching process is the focus of this paper. A novel bioreactor for bioleaching was designed. Bioleaching was carried out using Pseudomonas chlororaphis. Bioleaching experiments using mixed particles of Au and Cu were performed and leachate contained 0.006 mg/L, 2823 mg/L Au+ and Cu2+ respectively. It showed when Cu existed, the concentrations of Au were extremely small. This provided the feasibility to separate Cu from Au. The method of orthogonal experimental design was employed in the simulation bioleaching experiments. Experimental results showed the optimized parameters for separating Cu from Au particles were pH 7.0, temperature 22.5 °C, and rotation speed 80 r/min. Based on the optimized parameters obtained, the bioreactor was operated for recovering mixed Au and Cu particles. 88.1 wt.% of Cu and 76.6 wt.% of Au were recovered. The paper contributed important information to recover precious metals from waste PCBs. PMID:26316021

  3. Evaluation of the High-Heel Roof-to-Wall Connection with Extended OSB Wall Sheathing

    Treesearch

    Andrew DeRenzis; Vladimir Kochkin; Xiping Wang

    2013-01-01

    A recently completed testing project conducted to evaluate optimized structural roof-to-wall attachment solutions demonstrated the effectiveness of wood structural panels in restraining high-heel trusses against rotation. This study was designed to further evaluate the performance of OSB wall sheathing panels extended over the high-heel truss in resisting combined...

  4. Cell Separations in Microgravity and Development of a Space Bioreactor

    NASA Technical Reports Server (NTRS)

    Morrison, D. R.

    1985-01-01

    A bioreactor optimized for operations in space is now being developed. The current research is focused on determining the optimum cell-bead ratios, medium content and proper maintenance conditions required to keep living cell specimens alive and healthy for the entire flight. The bioreactor development project has recently added a microprocessor/computer to the JSC prototype for control and data analysis. Appropriate new technology is being combined with the current bioreactor designs and tested to determine what specific features must be included in the fabrication of a bioreactor designed to operate for STS demonstration tests. Considerations include: (1) circulation and resupply of culture media; (2) sensors required to monitor temperature, cell growth, mass transport, and oxygen consumption; and (3) inflight control of shear stress on cells, gas transfer in microgravity, diffusion, and intracellular transport. These data and results from the JSC prototype bioreactor test will be used for the design and construction of a small space bioreactor for the Orbiter middeck.

  5. Wall Interference Study of the NTF Slotted Tunnel Using Bodies of Revolution Wall Signature Data

    NASA Technical Reports Server (NTRS)

    Iyer, Venkit; Kuhl, David D.; Walker, Eric L.

    2004-01-01

    This paper is a description of the analysis of blockage corrections for bodies of revolution for the slotted-wall configuration of the National Transonic Facility (NTF) at the NASA Langley Research Center (LaRC). A wall correction method based on the measured wall signature is used. Test data from three different-sized blockage bodies and four wall ventilation settings were analyzed at various Mach numbers and unit Reynolds numbers. The results indicate that with the proper selection of the boundary condition parameters, the wall correction method can predict blockage corrections consistent with the wall measurements for Mach numbers as high as 0.95.

  6. Novel Approaches to Cellular Transplantation from the US Space Program

    NASA Technical Reports Server (NTRS)

    Pellis, Neal R.; Homick, Jerry L. (Technical Monitor)

    1999-01-01

    host immune rejection; (3) protection from the autoimmune component of the disease; and (4) anatomic placement of the engrafted cells that permits timely response to blood sugar levels as well as effective release and deployment of insulin. Bioreactor technology may provide some critical advances for surmounting some of these scientific hurdles. The NASA bioreactor is a horizontally rotating cylinder that is completely filled with culture medium. Gaseous exchange is maintained by a concentric cylinder of permeable silicon. In slow rotation (15-25 rpm) particles of small mass such as cells and tissue aggregates remain suspended in the rotating body of fluid. This novel approach suspends cells without stirring thus, allowing objects of different size mass to colocate and interact in a very low shear environment. In fact, analysis of the forces acting on individual cells in the rotating bioreactor reveals that the cells are continuously falling through the fluid medium. The conditions in the bioreactor permit assembly of cells into aggregates. three-dimensional tissue growth, synthesis of intercellular matrix,10 differentiation, and some sinusoid formations that may serve as a surrogate vasculature for larger tissue segments.

  7. NASA-JSC Protocol for the Characterization of Single Wall Carbon Nanotube Material Quality

    NASA Technical Reports Server (NTRS)

    Arepalli, Sivaram; Nikolaev, Pasha; Gorelik, Olga; Hadjiev, Victor; Holmes, William; Devivar, Rodrigo; Files, Bradley; Yowell, Leonard

    2010-01-01

    It is well known that the raw as well as purified single wall carbon nanotube (SWCNT) material always contain certain amount of impurities of varying composition (mostly metal catalyst and non-tubular carbon). Particular purification method also creates defects and/or functional groups in the SWCNT material and therefore affects the its dispersability in solvents (important to subsequent application development). A number of analytical characterization tools have been used successfully in the past years to assess various properties of nanotube materials, but lack of standards makes it difficult to compare these measurements across the board. In this work we report the protocol developed at NASA-JSC which standardizes measurements using TEM, SEM, TGA, Raman and UV-Vis-NIR absorption techniques. Numerical measures are established for parameters such as metal content, homogeneity, thermal stability and dispersability, to allow easy comparison of SWCNT materials. We will also report on the recent progress in quantitative measurement of non-tubular carbon impurities and a possible purity standard for SWCNT materials.

  8. Tapered bed bioreactor

    DOEpatents

    Scott, Charles D.; Hancher, Charles W.

    1977-01-01

    A vertically oriented conically shaped column is used as a fluidized bed bioreactor wherein biologically catalyzed reactions are conducted in a continuous manner. The column utilizes a packing material a support having attached thereto a biologically active catalytic material.

  9. Microgravity

    NASA Image and Video Library

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 deg. C (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  10. Microgravity

    NASA Image and Video Library

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 degreesC (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  11. Heat Flux and Wall Temperature Estimates for the NASA Langley HIFiRE Direct Connect Rig

    NASA Technical Reports Server (NTRS)

    Cuda, Vincent, Jr.; Hass, Neal E.

    2010-01-01

    An objective of the Hypersonic International Flight Research Experimentation (HIFiRE) Program Flight 2 is to provide validation data for high enthalpy scramjet prediction tools through a single flight test and accompanying ground tests of the HIFiRE Direct Connect Rig (HDCR) tested in the NASA LaRC Arc Heated Scramjet Test Facility (AHSTF). The HDCR is a full-scale, copper heat sink structure designed to simulate the isolator entrance conditions and isolator, pilot, and combustor section of the HIFiRE flight test experiment flowpath and is fully instrumented to assess combustion performance over a range of operating conditions simulating flight from Mach 5.5 to 8.5 and for various fueling schemes. As part of the instrumentation package, temperature and heat flux sensors were provided along the flowpath surface and also imbedded in the structure. The purpose of this paper is to demonstrate that the surface heat flux and wall temperature of the Zirconia coated copper wall can be obtained with a water-cooled heat flux gage and a sub-surface temperature measurement. An algorithm was developed which used these two measurements to reconstruct the surface conditions along the flowpath. Determinations of the surface conditions of the Zirconia coating were conducted for a variety of conditions.

  12. Wall of Rheasilvia

    NASA Image and Video Library

    2012-03-21

    This still from an animation made from data obtained by NASA Dawn spacecraft shows the topography of a portion of the wall and interior of the Rheasilvia impact basin in asteroid Vesta south-polar region.

  13. Design concepts for bioreactors in space

    NASA Technical Reports Server (NTRS)

    Seshan, P. K.; Peterson, G. R.; Beard, B.; Dunlop, E. H.

    1986-01-01

    Microbial food sources are becoming viable and more efficient alternatives to conventional food sources especially in the context of Closed Ecological Life Support Systems (CELSS) in space habitats. Since bioreactor designs for terrestrial operation will not readily apply to conditions of microgravity, there is an urgent need to learn about the differences. These differences cannot be easily estimated due to the complex nature of the mass transport and mixing mechanisms in fermenters. Therefore, a systematic and expeditious experimental program must be undertaken to obtain the engineering data necessary to lay down the foundations of designing bioreactors for microgravity. Two bioreactor design concepts presented represent two dissimilar approaches to grappling with the absence of gravity in space habitats and deserve to be tested for adoption as important components of the life support function aboard spacecrafts, space stations and other extra-terrestrial habitats.

  14. Fluid mechanics of spinner-flask bioreactors

    NASA Astrophysics Data System (ADS)

    Sucosky, Philippe; Neitzel, G. Paul

    2000-11-01

    The dynamic environment within bioreactors used for in vitro tissue growth has been observed to affect the development of mammalian cells. Many studies have shown that moderate mechanical stress enhances growth of some tissues whereas high shear levels and turbulence seem to damage cells. In order to optimize the design and the operating conditions of bioreactors, it is important to understand the fluid-dynamic characteristics and to control the stress levels within these devices. The present research focuses on the characterization of the flow field within a spinner-flask bioreactor. The dynamic properties of the flow are investigated experimentally using particle-image velocimetry with a refractive-index-matched model. Phase-locked ensemble-averaging is employed to provide some information on the turbulence characteristics of the model culture medium in the vicinity of a model tissue construct.

  15. Cultivation of mammalian cells using a single-use pneumatic bioreactor system.

    PubMed

    Obom, Kristina M; Cummings, Patrick J; Ciafardoni, Janelle A; Hashimura, Yasunori; Giroux, Daniel

    2014-10-10

    Recent advances in mammalian, insect, and stem cell cultivation and scale-up have created tremendous opportunities for new therapeutics and personalized medicine innovations. However, translating these advances into therapeutic applications will require in vitro systems that allow for robust, flexible, and cost effective bioreactor systems. There are several bioreactor systems currently utilized in research and commercial settings; however, many of these systems are not optimal for establishing, expanding, and monitoring the growth of different cell types. The culture parameters most challenging to control in these systems include, minimizing hydrodynamic shear, preventing nutrient gradient formation, establishing uniform culture medium aeration, preventing microbial contamination, and monitoring and adjusting culture conditions in real-time. Using a pneumatic single-use bioreactor system, we demonstrate the assembly and operation of this novel bioreactor for mammalian cells grown on micro-carriers. This bioreactor system eliminates many of the challenges associated with currently available systems by minimizing hydrodynamic shear and nutrient gradient formation, and allowing for uniform culture medium aeration. Moreover, the bioreactor's software allows for remote real-time monitoring and adjusting of the bioreactor run parameters. This bioreactor system also has tremendous potential for scale-up of adherent and suspension mammalian cells for production of a variety therapeutic proteins, monoclonal antibodies, stem cells, biosimilars, and vaccines.

  16. Nitrate Removal Rates in Denitrifying Bioreactors During Storm Flows

    NASA Astrophysics Data System (ADS)

    Pluer, W.; Walter, T.

    2017-12-01

    Field denitrifying bioreactors are designed to reduce excess nitrate (NO3-) pollution in runoff from agricultural fields. Field bioreactors saturate organic matter to create conditions that facilitate microbial denitrification. Prior studies using steady flow in lab-scale bioreactors showed that a hydraulic retention time (HRT) between 4 and 10 hours was optimal for reducing NO3- loads. However, during storm-induced events, flow rate and actual HRT fluctuate. These fluctuations have the potential to disrupt the system in significant ways that are not captured by the idealized steady-flow HRT models. The goal of this study was to investigate removal rate during dynamic storm flows of variable rates and durations. Our results indicate that storm peak flow and duration were not significant controlling variables. Instead, we found high correlations (p=0.004) in average removal rates between bioreactors displaying a predominantly uniform flow pattern compared with bioreactors that exhibited preferential flow (24.4 and 21.4 g N m-3 d-1, respectively). This suggests that the internal flow patterns are a more significant driver of removal rate than external factors of the storm hydrograph. Designing for flow patterns in addition to theoretical HRT will facilitate complete mixing within the bioreactors. This will help maximize excess NO3- removal during large storm-induced runoff events.

  17. Evaluation of woodchip bioreactors for improved water quality

    USDA-ARS?s Scientific Manuscript database

    Woodchip bioreactors are gaining popularity with farmers because of their edge-of-field nitrate removal capabilities, which do not require changes in land management practices. However, limited research has been conducted to study the potential of these bioreactors to also reduce downstream transpor...

  18. CFD simulation of liquid-liquid dispersions in a stirred tank bioreactor

    NASA Astrophysics Data System (ADS)

    Gelves, R.

    2013-10-01

    In this paper simulations were developed in order to allow the examinations of drop sizes in liquid-liquid dispersions (oil-water) in a stirred tank bioreactor using CFD simulations (Computational Fluid Dynamics). The effects of turbulence, rotating flow, drop breakage were simulated by using the k-e, MRF (Multiple Reference Frame) and PBM (Population Balance Model), respectively. The numerical results from different operational conditions are compared with experimental data obtained from an endoscope technique and good agreement is achieved. Motivated by these simulated and experimental results CFD simulations are qualified as a very promising tool for predicting hydrodynamics and drop sizes especially useful for liquid-liquid applications which are characterized by the challenging problem of emulsion stability due to undesired drop sizes.

  19. FLEXWAL: A computer program for predicting the wall modifications for two-dimensional, solid, adaptive-wall tunnels

    NASA Technical Reports Server (NTRS)

    Everhart, J. L.

    1983-01-01

    A program called FLEXWAL for calculating wall modifications for solid, adaptive-wall wind tunnels is presented. The method used is the iterative technique of NASA TP-2081 and is applicable to subsonic and transonic test conditions. The program usage, program listing, and a sample case are given.

  20. Open source software to control Bioflo bioreactors.

    PubMed

    Burdge, David A; Libourel, Igor G L

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW.

  1. Open Source Software to Control Bioflo Bioreactors

    PubMed Central

    Burdge, David A.; Libourel, Igor G. L.

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW. PMID:24667828

  2. Disposable Bioreactors for Plant Micropropagation and Mass Plant Cell Culture

    NASA Astrophysics Data System (ADS)

    Ducos, Jean-Paul; Terrier, Bénédicte; Courtois, Didier

    Different types of bioreactors are used at Nestlé R&D Centre - Tours for mass propagation of selected plant varieties by somatic embryogenesis and for large scale culture of plants cells to produce metabolites or recombinant proteins. Recent studies have been directed to cut down the production costs of these two processes by developing disposable cell culture systems. Vegetative propagation of elite plant varieties is achieved through somatic embryogenesis in liquid medium. A pilot scale process has recently been set up for the industrial propagation of Coffea canephora (Robusta coffee). The current production capacity is 3.0 million embryos per year. The pre-germination of the embryos was previously conducted by temporary immersion in liquid medium in 10-L glass bioreactors. An improved process has been developed using a 10-L disposable bioreactor consisting of a bag containing a rigid plastic box ('Box-in-Bag' bioreactor), insuring, amongst other advantages, a higher light transmittance to the biomass due to its horizontal design. For large scale cell culture, two novel flexible plastic-based disposable bioreactors have been developed from 10 to 100 L working volumes, validated with several plant species ('Wave and Undertow' and 'Slug Bubble' bioreactors). The advantages and the limits of these new types of bioreactor are discussed, based mainly on our own experience on coffee somatic embryogenesis and mass cell culture of soya and tobacco.

  3. A versatile modular bioreactor platform for Tissue Engineering

    PubMed Central

    Schuerlein, Sebastian; Schwarz, Thomas; Krziminski, Steffan; Gätzner, Sabine; Hoppensack, Anke; Schwedhelm, Ivo; Schweinlin, Matthias; Walles, Heike

    2016-01-01

    Abstract Tissue Engineering (TE) bears potential to overcome the persistent shortage of donor organs in transplantation medicine. Additionally, TE products are applied as human test systems in pharmaceutical research to close the gap between animal testing and the administration of drugs to human subjects in clinical trials. However, generating a tissue requires complex culture conditions provided by bioreactors. Currently, the translation of TE technologies into clinical and industrial applications is limited due to a wide range of different tissue‐specific, non‐disposable bioreactor systems. To ensure a high level of standardization, a suitable cost‐effectiveness, and a safe graft production, a generic modular bioreactor platform was developed. Functional modules provide robust control of culture processes, e.g. medium transport, gas exchange, heating, or trapping of floating air bubbles. Characterization revealed improved performance of the modules in comparison to traditional cell culture equipment such as incubators, or peristaltic pumps. By combining the modules, a broad range of culture conditions can be achieved. The novel bioreactor platform allows using disposable components and facilitates tissue culture in closed fluidic systems. By sustaining native carotid arteries, engineering a blood vessel, and generating intestinal tissue models according to a previously published protocol the feasibility and performance of the bioreactor platform was demonstrated. PMID:27492568

  4. Upflow bioreactor with septum and pressure release mechanism

    DOEpatents

    Hansen, Conly L.; Hansen, Carl S.; Pack, Kevin; Milligan, John; Benefiel, Bradley C.; Tolman, C. Wayne; Tolman, Kenneth W.

    2010-04-20

    An upflow bioreactor includes a vessel having an inlet and an outlet configured for upflow operation. A septum is positioned within the vessel and defines a lower chamber and an upper chamber. The septum includes an aperture that provides fluid communication between the upper chamber and lower chamber. The bioreactor also includes means for releasing pressure buildup in the lower chamber. In one configuration, the septum includes a releasable portion having an open position and a closed position. The releasable portion is configured to move to the open position in response to pressure buildup in the lower chamber. In the open position fluid communication between the lower chamber and the upper chamber is increased. Alternatively the lower chamber can include a pressure release line that is selectively actuated by pressure buildup. The pressure release mechanism can prevent the bioreactor from plugging and/or prevent catastrophic damage to the bioreactor caused by high pressures.

  5. New NASA Images of Irma's Towering Clouds (Anaglyph)

    NASA Image and Video Library

    2017-09-08

    On Sept. 7, the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite passed over Hurricane Irma at approximately 11:20 am local time. The MISR instrument comprises nine cameras that view the Earth at different angles, and since it takes roughly seven minutes for all nine cameras to capture the same location, the motion of the clouds between images allows scientists to calculate the wind speed at the cloud tops. This stereo anaglyph combines two of the MISR angles to show a three-dimensional view of Irma. You will need red-blue glasses to view the anaglyph; place the red lens over your left eye. At this time, Irma's eye was located approximately 60 miles (100 kilometers) north of the Dominican Republic and 140 miles (230 kilometers) north of its capital, Santo Domingo. Irma was a powerful Category 5 hurricane, with wind speeds at the ocean surface up to 185 miles (300 kilometers) per hour. The MISR data show that at cloud top, winds near the eye wall (the most destructive part of the storm) were approximately 90 miles per hour (145 kilometers per hour), and the maximum cloud-top wind speed throughout the storm calculated by MISR was 135 miles per hour (220 kilometers per hour). While the hurricane's dominant rotation direction is counter-clockwise, winds near the eye wall are consistently pointing outward from it. This is an indication of outflow, the process by which a hurricane draws in warm, moist air at the surface and ejects cool, dry air at its cloud tops. https://photojournal.jpl.nasa.gov/catalog/PIA21945

  6. Fluidized-bed bioreactor process for the microbial solubiliztion of coal

    DOEpatents

    Scott, Charles D.; Strandberg, Gerald W.

    1989-01-01

    A fluidized-bed bioreactor system for the conversion of coal into microbially solubilized coal products. The fluidized-bed bioreactor continuously or periodically receives coal and bio-reactants and provides for the production of microbially solubilized coal products in an economical and efficient manner. An oxidation pretreatment process for rendering coal uniformly and more readily susceptible to microbial solubilization may be employed with the fluidized-bed bioreactor.

  7. Simplified Bioreactor For Growing Mammalian Cells

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn F.

    1995-01-01

    Improved bioreactor for growing mammalian cell cultures developed. Designed to support growth of dense volumes of mammalian cells by providing ample, well-distributed flows of nutrient solution with minimal turbulence. Cells relatively delicate and, unlike bacteria, cannot withstand shear forces present in turbulent flows. Bioreactor vessel readily made in larger sizes to accommodate greater cell production quantities. Molding equipment presently used makes cylinders up to 30 centimeters long. Alternative sintered plastic techniques used to vary pore size and quantity, as necessary.

  8. Membrane fouling control using a rotary disk in a submerged anaerobic membrane sponge bioreactor.

    PubMed

    Kim, Jungmin; Shin, Jaewon; Kim, Hyemin; Lee, Jung-Yeol; Yoon, Min-Hyuk; Won, Seyeon; Lee, Byung-Chan; Song, Kyung Guen

    2014-11-01

    Despite significant research efforts over the last few decades, membrane fouling in anaerobic membrane bioreactors (AnMBRs) remains an unsolved problem that increases the overall operational costs and obstructs the industrial applications. Herein, we developed a method for effectively controlling the membrane fouling in a sponge-submerged AnMBRs using an anaerobic rotary disk MBR (ARMBR). The disk rotation led the effective collision between the sponge and membrane surface; thus successfully enhanced the membrane permeability in the ARMBR. The effect of the disk rotational speed and sponge volume fraction on the membrane permeability and the relationship between the water flow direction and membrane permeability were investigated. The long-term feasibility was tested over 100days of synthetic wastewater treatment. As a result, stable and economical performance was observed without membrane replacement and washing. The proposed integrated rotary disk-supporting media appears to be a feasible and even beneficial option in the AnMBR technology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Streamlined bioreactor-based production of human cartilage tissues.

    PubMed

    Tonnarelli, B; Santoro, R; Adelaide Asnaghi, M; Wendt, D

    2016-05-27

    Engineered tissue grafts have been manufactured using methods based predominantly on traditional labour-intensive manual benchtop techniques. These methods impart significant regulatory and economic challenges, hindering the successful translation of engineered tissue products to the clinic. Alternatively, bioreactor-based production systems have the potential to overcome such limitations. In this work, we present an innovative manufacturing approach to engineer cartilage tissue within a single bioreactor system, starting from freshly isolated human primary chondrocytes, through the generation of cartilaginous tissue grafts. The limited number of primary chondrocytes that can be isolated from a small clinically-sized cartilage biopsy could be seeded and extensively expanded directly within a 3D scaffold in our perfusion bioreactor (5.4 ± 0.9 doublings in 2 weeks), bypassing conventional 2D expansion in flasks. Chondrocytes expanded in 3D scaffolds better maintained a chondrogenic phenotype than chondrocytes expanded on plastic flasks (collagen type II mRNA, 18-fold; Sox-9, 11-fold). After this "3D expansion" phase, bioreactor culture conditions were changed to subsequently support chondrogenic differentiation for two weeks. Engineered tissues based on 3D-expanded chondrocytes were more cartilaginous than tissues generated from chondrocytes previously expanded in flasks. We then demonstrated that this streamlined bioreactor-based process could be adapted to effectively generate up-scaled cartilage grafts in a size with clinical relevance (50 mm diameter). Streamlined and robust tissue engineering processes, as the one described here, may be key for the future manufacturing of grafts for clinical applications, as they facilitate the establishment of compact and closed bioreactor-based production systems, with minimal automation requirements, lower operating costs, and increased compliance to regulatory guidelines.

  10. NASA Thesaurus Supplement: A Three-Part Cumulative Update of the 1998 Edition of the NASA Thesaurus

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA Thesaurus Supplement is a cumulative update to the 1998 edition of the NASA Thesaurus (NASA/SP-1998-7501). The Supplement, published every six months, includes all new terms and associated hierarchies added since the cutoff for the 1998 edition (December 1997). Parts 1 and 2 (Hierarchical Listing and Rotated Term Display) correspond to Volumes 1 and 2 of the 1998 printed edition of the NASA Thesaurus. Definitions are included in Part 1; uppercase/lowercase forms are provided in both Parts 1 and 2. Part 3 is a list of deletions or changes to valid terms.

  11. A multiphysics 3D model of tissue growth under interstitial perfusion in a tissue-engineering bioreactor.

    PubMed

    Nava, Michele M; Raimondi, Manuela T; Pietrabissa, Riccardo

    2013-11-01

    The main challenge in engineered cartilage consists in understanding and controlling the growth process towards a functional tissue. Mathematical and computational modelling can help in the optimal design of the bioreactor configuration and in a quantitative understanding of important culture parameters. In this work, we present a multiphysics computational model for the prediction of cartilage tissue growth in an interstitial perfusion bioreactor. The model consists of two separate sub-models, one two-dimensional (2D) sub-model and one three-dimensional (3D) sub-model, which are coupled between each other. These sub-models account both for the hydrodynamic microenvironment imposed by the bioreactor, using a model based on the Navier-Stokes equation, the mass transport equation and the biomass growth. The biomass, assumed as a phase comprising cells and the synthesised extracellular matrix, has been modelled by using a moving boundary approach. In particular, the boundary at the fluid-biomass interface is moving with a velocity depending from the local oxygen concentration and viscous stress. In this work, we show that all parameters predicted, such as oxygen concentration and wall shear stress, by the 2D sub-model with respect to the ones predicted by the 3D sub-model are systematically overestimated and thus the tissue growth, which directly depends on these parameters. This implies that further predictive models for tissue growth should take into account of the three dimensionality of the problem for any scaffold microarchitecture.

  12. Multimembrane Bioreactor

    NASA Technical Reports Server (NTRS)

    Cho, Toohyon; Shuler, Michael L.

    1989-01-01

    Set of hydrophilic and hydrophobic membranes in bioreactor allows product of reaction to be separated, while nutrients fed to reacting cells and byproducts removed from them. Separation process requires no externally supplied energy; free energy of reaction sufficient. Membranes greatly increase productivity of metabolizing cells by continuously removing product and byproducts, which might otherwise inhibit reaction, and by continuously adding oxygen and organic nutrients.

  13. Fluidized-bed bioreactor system for the microbial solubilization of coal

    DOEpatents

    Scott, C.D.; Strandberg, G.W.

    1987-09-14

    A fluidized-bed bioreactor system for the conversion of coal into microbially solubilized coal products. The fluidized-bed bioreactor continuously or periodically receives coal and bio-reactants and provides for the production of microbially solubilized coal products in an economical and efficient manner. An oxidation pretreatment process for rendering coal uniformly and more readily susceptible to microbial solubilization may be employed with the fluidized-bed bioreactor. 2 figs.

  14. A versatile modular bioreactor platform for Tissue Engineering.

    PubMed

    Schuerlein, Sebastian; Schwarz, Thomas; Krziminski, Steffan; Gätzner, Sabine; Hoppensack, Anke; Schwedhelm, Ivo; Schweinlin, Matthias; Walles, Heike; Hansmann, Jan

    2017-02-01

    Tissue Engineering (TE) bears potential to overcome the persistent shortage of donor organs in transplantation medicine. Additionally, TE products are applied as human test systems in pharmaceutical research to close the gap between animal testing and the administration of drugs to human subjects in clinical trials. However, generating a tissue requires complex culture conditions provided by bioreactors. Currently, the translation of TE technologies into clinical and industrial applications is limited due to a wide range of different tissue-specific, non-disposable bioreactor systems. To ensure a high level of standardization, a suitable cost-effectiveness, and a safe graft production, a generic modular bioreactor platform was developed. Functional modules provide robust control of culture processes, e.g. medium transport, gas exchange, heating, or trapping of floating air bubbles. Characterization revealed improved performance of the modules in comparison to traditional cell culture equipment such as incubators, or peristaltic pumps. By combining the modules, a broad range of culture conditions can be achieved. The novel bioreactor platform allows using disposable components and facilitates tissue culture in closed fluidic systems. By sustaining native carotid arteries, engineering a blood vessel, and generating intestinal tissue models according to a previously published protocol the feasibility and performance of the bioreactor platform was demonstrated. © 2017 The Authors. Biotechnology Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. [Study of shear rate in modified airlift nitrifying bioreactor].

    PubMed

    Jin, Ren-cun; Zheng, Ping

    2006-06-01

    The characteristics of shear rate in an airlift nitrifying bioreactor and its influencing factors were studied. The results showed that the shear rate was different in different sections of the bioreactor. With inlet gas flowrate at 430 approximately 2700 L x h(-1), the overall shear rate was (0.702 approximately 3.13) x 10(5) s(-1), shear rate in riser was (1.07 approximately 31.3) x 10(5) s(-1) and in gas-liquid separator was (1.12 approximately 25.0) x 10(5) s(-1), respectively. It indicates that the highest shear rates prevailed in the riser part of bioreactor. The operational variables and the bioreactor configurations exerted a significant influence on the shear level of the bioreactor. When inlet gas flowrate was raised from 1300 to 2700 L x h(-1), shear rate in riser and separator ascended first and then descended subsequently. The diameter of draft tube (d) was negatively correlated with shear rate. When the draft tube with diameter of 5.5 cm was installed, the shear rates in riser, separator and overall shear rate were 85.5%, 82.3% and 80.6%, respectively less as compared with that with diameter of 4.0 cm. The number of static mixers (N) was positively correlated with the shear rate. When d was set at 4.0 cm, with N of 10 and 39, the shear rates in riser were 6.14 and 7.97 times higher respectively, than that of conventional bioreactor. The ratio of maximum local shear rate to overall shear rate was 3.68 approximately 7.66, and the homogeneity of the shear field in airlift bioreactors could be improved if d and N were set at 5.5 cm and 10 approximately 13, respectively.

  16. Measurements of the Structure of the Plasma Rotation in Slowly Rotating Tearing Modes in DIII-D

    NASA Astrophysics Data System (ADS)

    Taylor, N. Z.; Ferraro, N. M.; La Haye, R. J.; Petty, C. C.; Bowman, C.

    2014-10-01

    A helically modified ion flow by an island can lead to helical ion polarization currents which can affect tearing mode stability. This issue is of particular importance to ITER where large inertia and relatively low torque will likely result in low rotation. In DIII-D cases either (1) a m/n = 2/1 mode is slowed down to ~1 kHz (faster than the inverse wall time) by near balanced neutral beams or (2) an island is entrained by applied rotating n = 1 magnetic field at 10 Hz (slower than the inverse wall time). The n = 1 island structure is measured with electron cyclotron emission radiometry. The ion rotation and temperature are measured by fast resolution (274 μ s) charge exchange recombination (CER) spectroscopy in the 1 kHz freely rotating case and by standard CER (5 ms) in the 10 Hz entrainment. Tangential and vertical CER arrays allow for the radial profile of the helically perturbed rotation to be determined. A comparison of the measured nonlinear island structures with that from the linear resistive stability code M3D-C1 will be presented. Work supported in part by the US Department of Energy under DE-FG02-95ER54309 and DE-FC02-04ER54698.

  17. Shoulder kinematics during the wall push-up plus exercise.

    PubMed

    Lunden, Jason B; Braman, Jonathan P; Laprade, Robert F; Ludewig, Paula M

    2010-03-01

    The push-up plus exercise is a common therapeutic exercise for improving shoulder function and treating shoulder pathology. To date, the kinematics of the push-up plus exercise have not been studied. Our hypothesis was that the wall push-up plus exercise would demonstrate increased scapular internal rotation and increased humeral anterior translation during the plus phase of the exercise, thereby potentially impacting the subacromial space. Bone pins were inserted in the humerus and scapula in 12 healthy volunteers with no history of shoulder pathology. In vivo motion during the wall push-up plus exercise was tracked using an electromagnetic tracking system. During the wall push-up plus exercise, from a starting position to the push-up plus position, there was a significant increase in scapular downward rotation (P < .05) and internal rotation (P < .05). The pattern of glenohumeral motion was humeral elevation (P < .05) and movement anterior to the scapular plane (P < .05), with humeral external rotation remaining relatively constant. We found that during a wall push-up plus exercise in healthy volunteers, the scapula was placed in a position potentially associated with shoulder impingement. Because of the shoulder kinematics of the wall push-up plus exercise, utilization of this exercise without modification early on in shoulder rehabilitation, especially in patients with subacromial impingement, should be considered cautiously. Copyright 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  18. NASA/ASEE Summer Faculty Fellowship Program, 1990, Volume 1

    NASA Technical Reports Server (NTRS)

    Bannerot, Richard B. (Editor); Goldstein, Stanley H. (Editor)

    1990-01-01

    The 1990 Johnson Space Center (JSC) NASA/American Society for Engineering Education (ASEE) Summer Faculty Fellowship Program was conducted by the University of Houston-University Park and JSC. A compilation of the final reports on the research projects are presented. The topics covered include: the Space Station; the Space Shuttle; exobiology; cell biology; culture techniques; control systems design; laser induced fluorescence; spacecraft reliability analysis; reduced gravity; biotechnology; microgravity applications; regenerative life support systems; imaging techniques; cardiovascular system; physiological effects; extravehicular mobility units; mathematical models; bioreactors; computerized simulation; microgravity simulation; and dynamic structural analysis.

  19. Wind tunnel wall interference (January 1980 - May 1988): A selected, annotated bibliography

    NASA Technical Reports Server (NTRS)

    Tuttle, Marie H.; Cole, Karen L.

    1988-01-01

    This selected bibliography lists 423 entries on the subject of wall interference during testing in wind tunnels. It is the third in a series of bibliographies on the subject. The first, NASA TM-87639, August 1986, is concerned with the reduction of wall interference by the use of adaptive walls. The second, NASA TP-89066, December 1986, is on wall interference in V/STOL and high lift testing. This, the third in the series, covers the wall interference literature published during the period January 1980 through May 1988, generally excluding those topics covered in the first two parts.

  20. A comparison of orbitally-shaken and stirred-tank bioreactors: pH modulation and bioreactor type affect CHO cell growth and protein glycosylation.

    PubMed

    Monteil, Dominique T; Juvet, Valentin; Paz, Jonathan; Moniatte, Marc; Baldi, Lucia; Hacker, David L; Wurm, Florian M

    2016-09-01

    Orbitally shaken bioreactors (OSRs) support the suspension cultivation of animal cells at volumetric scales up to 200 L and are a potential alternative to stirred-tank bioreactors (STRs) due to their rapid and homogeneous mixing and high oxygen transfer rate. In this study, a Chinese hamster ovary cell line producing a recombinant antibody was cultivated in a 5 L OSR and a 3 L STR, both operated with or without pH control. Effects of bioreactor type and pH control on cell growth and metabolism and on recombinant protein production and glycosylation were determined. In pH-controlled bioreactors, the glucose consumption and lactate production rates were higher relative to cultures grown in bioreactors without pH control. The cell density and viability were higher in the OSRs than in the STRs, either with or without pH control. Volumetric recombinant antibody yields were not affected by the process conditions, and a glycan analysis of the antibody by mass spectrometry did not reveal major process-dependent differences in the galactosylation index. The results demonstrated that OSRs are suitable for recombinant protein production from suspension-adapted animal cells. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1174-1180, 2016. © 2016 American Institute of Chemical Engineers.

  1. Denitrifying bioreactors for nitrate removal from tile drained cropland

    USDA-ARS?s Scientific Manuscript database

    Denitrification bioreactors are a promising technology for mitigation of nitrate-nitrogen (NO3-N) losses in subsurface drainage water. Bioreactors are constructed with carbon substrates, typically wood chips, to provide a substrate for denitrifying microorganisms. Researchers in Iowa found that for ...

  2. ADVANCING THE FIELD EVALUATIONS AND APPLICATIONS OF LANDFILL BIOREACTORS

    EPA Science Inventory

    The US Environmental Protection Agency (EPA) is undertaking a long-term program to conduct field evaluations of landfill bioreactors. The near-term effort is focused on the development of appropriate monitoring strategies to ensure adequate control of the landfill bioreactors an...

  3. Fixed-bed bioreactor system for the microbial solubilization of coal

    DOEpatents

    Scott, C.D.; Strandberg, G.W.

    1987-09-14

    A fixed-bed bioreactor system for the conversion of coal into microbially solubilized coal products. The fixed-bed bioreactor continuously or periodically receives coal and bio-reactants and provides for the large scale production of microbially solubilized coal products in an economical and efficient manner. An oxidation pretreatment process for rendering coal uniformly and more readily susceptible to microbial solubilization may be employed with the fixed-bed bioreactor. 1 fig., 1 tab.

  4. Call for NASA Mission Supporting Observations

    NASA Astrophysics Data System (ADS)

    Binzel, Richard P.

    2018-04-01

    Lightcurve observations are requested to support NASA missions planned for launch to study main-belt and Trojan asteroids. In some cases, the rotations of the target asteroids are unknown. In other cases, the periods are well established and ongoing measurements will deliver the precision needed to deduce the rotation phase at the time of encounter more than a decade away.

  5. Modular bioreactor for the remediation of liquid streams and methods for using the same

    DOEpatents

    Noah, Karl S.; Sayer, Raymond L.; Thompson, David N.

    1998-01-01

    The present invention is directed to a bioreactor system for the remediation of contaminated liquid streams. The bioreactor system is composed of at least one and often a series of sub-units referred to as bioreactor modules. The modular nature of the system allows bioreactor systems be subdivided into smaller units and transported to waste sites where they are combined to form bioreactor systems of any size. The bioreactor modules further comprises reactor fill materials in the bioreactor module that remove the contaminants from the contaminated stream. To ensure that the stream thoroughly contacts the reactor fill materials, each bioreactor module comprises means for directing the flow of the stream in a vertical direction and means for directing the flow of the stream in a horizontal direction. In a preferred embodiment, the reactor fill comprises a sulfate reducing bacteria which is particularly useful for precipitating metals from acid mine streams.

  6. Plantform Bioreactor for Mass Micropropagation of Date Palm.

    PubMed

    Almusawi, Abdulminam H A; Sayegh, Abdullah J; Alshanaw, Ansam M S; Griffis, John L

    2017-01-01

    A novel protocol for the commercial production of date palm through micropropagation is presented. This protocol includes the use of a semisolid medium alternation or in combination with a temporary immersion system (TIS, Plantform bioreactor) in date palm micropropagation. The use of the Plantform bioreactor for date palm results in an improved multiplication rate, reduced micropropagation time, and improved weaning success. It also reduces the cost of saleable units and thus improves economic return for commercial micropropagation. The use of the Plantform bioreactor successfully addresses other hindrances that can occur during the scale-up of date palm micropropagation, including asynchrony of somatic embryos, limited maturation of somatic embryos, and highly variable germination frequencies of embryos.

  7. Direct numerical simulation of turbulent flow in a rotating square duct

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dai, Yi-Jun; Huang, Wei-Xi, E-mail: hwx@tsinghua.edu.cn; Xu, Chun-Xiao

    A fully developed turbulent flow in a rotating straight square duct is simulated by direct numerical simulations at Re{sub τ} = 300 and 0 ≤ Ro{sub τ} ≤ 40. The rotating axis is parallel to two opposite walls of the duct and normal to the main flow. Variations of the turbulence statistics with the rotation rate are presented, and a comparison with the rotating turbulent channel flow is discussed. Rich secondary flow patterns in the cross section are observed by varying the rotation rate. The appearance of a pair of additional vortices above the pressure wall is carefully examined, andmore » the underlying mechanism is explained according to the budget analysis of the mean momentum equations.« less

  8. Plant cell cultures: bioreactors for industrial production.

    PubMed

    Ruffoni, Barbara; Pistelli, Laura; Bertoli, Alessandra; Pistelli, Luisa

    2010-01-01

    The recent biotechnology boom has triggered increased interest in plant cell cultures, since a number of firms and academic institutions investigated intensively to rise the production of very promising bioactive compounds. In alternative to wild collection or plant cultivation, the production of useful and valuable secondary metabolites in large bioreactors is an attractive proposal; it should contribute significantly to future attempts to preserve global biodiversity and alleviate associated ecological problems. The advantages of such processes include the controlled production according to demand and a reduced man work requirement. Plant cells have been grown in different shape bioreactors, however, there are a variety of problems to be solved before this technology can be adopted on a wide scale for the production of useful plant secondary metabolites. There are different factors affecting the culture growth and secondary metabolite production in bioreactors: the gaseous atmosphere, oxygen supply and CO2 exchange, pH, minerals, carbohydrates, growth regulators, the liquid medium rheology and cell density. Moreover agitation systems and sterilization conditions may negatively influence the whole process. Many types ofbioreactors have been successfully used for cultivating transformed root cultures, depending on both different aeration system and nutrient supply. Several examples of medicinal and aromatic plant cultures were here summarized for the scale up cultivation in bioreactors.

  9. Schematic construction of flanged nanobearings from double-walled carbon nanotubes.

    PubMed

    Shenai, Prathamesh Mahesh; Zhao, Yang

    2010-08-01

    The performance of nanobearings constructed from double walled carbon nanotubes is considered to be crucially dependent on the initial rotational speed. Wearless rotation ceases for a nanobearing operating beyond a certain angular velocity. We propose a new design of nanobearings by manipulation of double walled carbon nanotubes leading to a flanged structure which possesses a built-in hindrance to the intertube oscillation without obstructing rotational motion. Through blocking the possible leakage path for rotational kinetic energy to the intertube oscillatory motion, the flanged bearing lowers its dissipative tendency when set into motion. Using molecular dynamics, it is shown that on account of its distinctive structure, the flanged bearing has superior operating characteristics and a broader working domain.

  10. Cavitation in centrifugal pump with rotating walls of axial inlet device

    NASA Astrophysics Data System (ADS)

    Moloshnyi, O.; Sotnyk, M.

    2017-08-01

    The article deals with the analysis of cavitation processes in the flowing part of the double entry centrifugal pump. The analysis is conducted using numerical modeling of the centrifugal pump operating process in the software environment ANSYS CFX. Two models of the axial inlet device is researched. It is shaped by a cylindrical section and diffuser section in front of the impeller, which includes fairing. The walls of the axial inlet device rotate with the same speed as the pump rotor. The numerical experiment is conducted under the condition of the flow rate change and absolute pressure at the inlet. The analysis shows that the pump has the average statistical cavitation performance. The occurrence of the cavitation in the axial inlet device is after narrowing the cross-section of flow channel and at the beginning of the diffuser section. Additional sudden expansion at the outlet of the axial inlet diffuser section does not affect the cavitation characteristics of the impeller, however, improves cavitation characteristics of the axial inlet device. For considered geometric parameters of the axial inlet device the cavitation in the impeller begins earlier than in the axial inlet device. That is, the considered design of the axial inlet device will not be subjected to destruction at the ensuring operation without cavitation in the impeller.

  11. Magnetization reversal in ferromagnetic spirals via domain wall motion

    NASA Astrophysics Data System (ADS)

    Schumm, Ryan D.; Kunz, Andrew

    2016-11-01

    Domain wall dynamics have been investigated in a variety of ferromagnetic nanostructures for potential applications in logic, sensing, and recording. We present a combination of analytic and simulated results describing the reliable field driven motion of a domain wall through the arms of a ferromagnetic spiral nanowire. The spiral geometry is capable of taking advantage of the benefits of both straight and circular wires. Measurements of the in-plane components of the spirals' magnetization can be used to determine the angular location of the domain wall, impacting the magnetoresistive applications dependent on the domain wall location. The spirals' magnetization components are found to depend on the spiral parameters: the initial radius and spacing between spiral arms, along with the domain wall location. The magnetization is independent of the parameters of the rotating field used to move the domain wall, and therefore the model is valid for current induced domain wall motion as well. The speed of the domain wall is found to depend on the frequency of the rotating driving field, and the domain wall speeds can be reliably varied over several orders of magnitude. We further demonstrate a technique capable of injecting multiple domain walls and show the reliable and unidirectional motion of domain walls through the arms of the spiral.

  12. Modular bioreactor for the remediation of liquid streams and methods for using the same

    DOEpatents

    Noah, K.S.; Sayer, R.L.; Thompson, D.N.

    1998-06-30

    The present invention is directed to a bioreactor system for the remediation of contaminated liquid streams. The bioreactor system is composed of at least one and often a series of sub-units referred to as bioreactor modules. The modular nature of the system allows bioreactor systems be subdivided into smaller units and transported to waste sites where they are combined to form bioreactor systems of any size. The bioreactor modules further comprises reactor fill materials in the bioreactor module that remove the contaminants from the contaminated stream. To ensure that the stream thoroughly contacts the reactor fill materials, each bioreactor module comprises means for directing the flow of the stream in a vertical direction and means for directing the flow of the stream in a horizontal direction. In a preferred embodiment, the reactor fill comprises a sulfate reducing bacteria which is particularly useful for precipitating metals from acid mine streams. 6 figs.

  13. Staying alive! Sensors used for monitoring cell health in bioreactors.

    PubMed

    O'Mara, P; Farrell, A; Bones, J; Twomey, K

    2018-01-01

    Current and next generation sensors such as pH, dissolved oxygen (dO) and temperature sensors that will help drive the use of single-use bioreactors in industry are reviewed. The current trend in bioreactor use is shifting from the traditional fixed bioreactors to the use of single-use bioreactors (SUBs). However as the shift in paradigm occurs there is now a greater need for sensor technology to play 'catch up' with the innovation of bioreactor technology. Many of the sensors still in use today rely on technology created in the 1960's such as the Clark-type dissolved oxygen sensor or glass pH electrodes. This is due to the strict requirements of sensors to monitor bioprocesses resulting in the use of traditional well understood methods, making it difficult to incorporate new sensor technology into industry. A number of advances in sensor technology have been achieved in recent years, a few of these advances and future research will also be discussed in this review. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Modified rotating biological contactor for removal of dichloromethane vapours.

    PubMed

    Ravi, R; Philip, Ligy; Swaminathan, T

    2015-01-01

    Bioreactors are used for the treatment of waste gas and odour that has gained much acceptance in the recent years to treat volatile organic compounds (VOCs). The different types of bioreactors (biofilter, biotrickling filter and bioscrubber) have been used for waste gas treatment. Each of these reactors has some advantages and some limitations. Though biodegradation is the main process for the removal of the pollutants, the mechanisms of removal and the microbial communities may differ among these bioreactors. Consequently, their performance or removal efficiency may also be different. Clogging of reactor and pressure drop are the main problems. In this study attempts are made to use the principle of rotating biological contactor (RBC) used for wastewater treatment for the removal of VOC. To overcome the above problem the RBC is modified which is suitable for the treatment of VOC (dichloromethane, DCM). DCM is harmful to human health and hazardous to the atmospheric environment. Modified RBC had no clogging problems and no pressure drop. So, it can handle the pollutant load for a longer period of time. A maximum elimination capacity of 25.7 g/m3 h has been achieved in this study for the DCM inlet load of 58 g/m3 h. The average biofilm thickness is 1 mm. The transient behaviour of the modified RBC treating DCM was investigated. The modified RBC is able to handle shutdown, restart and shock loading operations.

  15. The Potential for Microalgae as Bioreactors to Produce Pharmaceuticals

    PubMed Central

    Yan, Na; Fan, Chengming; Chen, Yuhong; Hu, Zanmin

    2016-01-01

    As photosynthetic organisms, microalgae can efficiently convert solar energy into biomass. Microalgae are currently used as an important source of valuable natural biologically active molecules, such as carotenoids, chlorophyll, long-chain polyunsaturated fatty acids, phycobiliproteins, carotenoids and enzymes. Significant advances have been achieved in microalgae biotechnology over the last decade, and the use of microalgae as bioreactors for expressing recombinant proteins is receiving increased interest. Compared with the bioreactor systems that are currently in use, microalgae may be an attractive alternative for the production of pharmaceuticals, recombinant proteins and other valuable products. Products synthesized via the genetic engineering of microalgae include vaccines, antibodies, enzymes, blood-clotting factors, immune regulators, growth factors, hormones, and other valuable products, such as the anticancer agent Taxol. In this paper, we briefly compare the currently used bioreactor systems, summarize the progress in genetic engineering of microalgae, and discuss the potential for microalgae as bioreactors to produce pharmaceuticals. PMID:27322258

  16. Microgravity

    NASA Image and Video Library

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens of cartilage tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. Constructs grown on Mir (A) tended to become more spherical, whereas those grown on Earth (B) maintained their initial disc shape. These findings might be related to differences in cultivation conditions, i.e., videotapes showed that constructs floated freely in microgravity but settled and collided with the rotating vessel wall at 1g (Earth's gravity). In particular, on Mir the constructs were exposed to uniform shear and mass transfer at all surfaces such that the tissue grew equally in all directions, whereas on Earth the settling of discoid constructs tended to align their flat circular areas perpendicular to the direction of motion, increasing shear and mass transfer circumferentially such that the tissue grew preferentially in the radial direction. A and B are full cross sections of constructs from Mir and Earth groups shown at 10-power. C and D are representative areas at the construct surfaces enlarged to 200-power. They are stained red with safranin-O. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Photo credit: Proceedings of the National Academy of Sciences.

  17. Microgravity

    NASA Image and Video Library

    1998-10-10

    Isolation of human mammary epithelial cells (HMEC) from breast cancer susceptible tissue; A: Duct element recovered from breast tissue digest. B: Outgrowth of cells from duct element in upper right corner cultured in a standard dish; most cells spontaneousely die during early cell divisions, but a few will establish long-term growth. C: Isolate of long-term frowth HMEC from outgrowth of duct element; cells shown soon after isolation and in early full-cell contact growth in culture in a dish. D: same long-term growth HMEC, but after 3 weeks in late full-cell contact growth in a continuous culture in a dish. Note attempts to reform duct elements but this in two demensions in a dish rather than in three dimensions in tissue. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Richmond, NASA/Marshall Space Flight Center (MSFC).

  18. Start-up of membrane bioreactor and hybrid moving bed biofilm reactor-membrane bioreactor: kinetic study.

    PubMed

    Leyva-Díaz, J C; Poyatos, J M

    2015-01-01

    A hybrid moving bed biofilm reactor-membrane bioreactor (hybrid MBBR-MBR) system was studied as an alternative solution to conventional activated sludge processes and membrane bioreactors. This paper shows the results obtained from three laboratory-scale wastewater treatment plants working in parallel in the start-up and steady states. The first wastewater treatment plant was a MBR, the second one was a hybrid MBBR-MBR system containing carriers both in anoxic and aerobic zones of the bioreactor (hybrid MBBR-MBRa), and the last one was a hybrid MBBR-MBR system which contained carriers only in the aerobic zone (hybrid MBBR-MBRb). The reactors operated with a hydraulic retention time of 30.40 h. A kinetic study for characterizing heterotrophic biomass was carried out and organic matter and nutrients removals were evaluated. The heterotrophic biomass of the hybrid MBBR-MBRb showed the best kinetic performance in the steady state, with yield coefficient for heterotrophic biomass=0.30246 mg volatile suspended solids per mg chemical oxygen demand, maximum specific growth rate for heterotrophic biomass=0.00308 h(-1) and half-saturation coefficient for organic matter=3.54908 mg O2 L(-1). The removal of organic matter was supported by the kinetic study of heterotrophic biomass.

  19. NASA Thesaurus Supplement: A Three-Part Cumulative Update of the 1998 Edition of the NASA Thesaurus. Supplement 5

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The NASA Thesaurus Supplement is a cumulative update to the 1998 edition of the NASA Thesaurus (NASA/SP-1998-7501). The Supplement, published every 6 months, includes all new terms and associated hierarchies added since the cutoff for the 1998 edition (December 1997). Parts 1 and 2 (Hierarchical Listing and Rotated Term Display) correspond to Volumes 1 and 2 of the 1998 printed edition of the NASA Thesaurus. Definitions are included in Part 1; uppercase/lowercase forms are provided in both Parts 1 and 2. Part 3 is a list of deletions or changes to valid terms.

  20. NASA Thesaurus Supplement: A Three-Part Cumulative Update of the 1998 Edition of the NASA Thesaurus. Supplement 7

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA Thesaurus Supplement is a cumulative update to the 1998 edition of the NASA Thesaurus (NASA/SP-1998-7501). The Supplement, published every six months, includes all new terms and associated hierarchies added since the cutoff for the 1998 edition (December 1997). Parts 1 and 2 (Hierarchical Listing and Rotated Term Display) correspond to Volumes 1 and 2 of the 1998 printed edition of the NASA Thesaurus. Definitions are included in Part 1; uppercase/lowercase forms are provided in both Parts 1 and 2. Part 3 is a list of deletions or changes to valid terms.

  1. Production of recombinant adeno-associated vectors using two bioreactor configurations at different scales

    PubMed Central

    Negrete, Alejandro; Kotin, Robert M.

    2007-01-01

    The conventional methods for producing recombinant adeno-associated virus (rAAV) rely on transient transfection of adherent mammalian cells. To gain acceptance and achieve current good manufacturing process (cGMP) compliance, clinical grade rAAV production process should have the following qualities: simplicity, consistency, cost effectiveness, and scalability. Currently, the only viable method for producing rAAV in large-scale, e.g.≥1016 particles per production run, utilizes Baculovirus Expression Vectors (BEVs) and insect cells suspension cultures. The previously described rAAV production in 40 L culture using a stirred tank bioreactor requires special conditions for implementation and operation not available in all laboratories. Alternatives to producing rAAV in stirred-tank bioreactors are single-use, disposable bioreactors, e.g. Wave™. The disposable bags are purchased pre-sterilized thereby eliminating the need for end-user sterilization and also avoiding cleaning steps between production runs thus facilitating the production process. In this study, rAAV production in stirred tank and Wave™ bioreactors was compared. The working volumes were 10 L and 40 L for the stirred tank bioreactors and 5 L and 20 L for the Wave™ bioreactors. Comparable yields of rAAV, ~2e+13 particles per liter of cell culture were obtained in all volumes and configurations. These results demonstrate that producing rAAV in large scale using BEVs is reproducible, scalable, and independent of the bioreactor configuration. Keywords: adeno-associated vectors; large-scale production; stirred tank bioreactor; wave bioreactor; gene therapy. PMID:17606302

  2. High-throughput miniaturized bioreactors for cell culture process development: reproducibility, scalability, and control.

    PubMed

    Rameez, Shahid; Mostafa, Sigma S; Miller, Christopher; Shukla, Abhinav A

    2014-01-01

    Decreasing the timeframe for cell culture process development has been a key goal toward accelerating biopharmaceutical development. Advanced Microscale Bioreactors (ambr™) is an automated micro-bioreactor system with miniature single-use bioreactors with a 10-15 mL working volume controlled by an automated workstation. This system was compared to conventional bioreactor systems in terms of its performance for the production of a monoclonal antibody in a recombinant Chinese Hamster Ovary cell line. The miniaturized bioreactor system was found to produce cell culture profiles that matched across scales to 3 L, 15 L, and 200 L stirred tank bioreactors. The processes used in this article involve complex feed formulations, perturbations, and strict process control within the design space, which are in-line with processes used for commercial scale manufacturing of biopharmaceuticals. Changes to important process parameters in ambr™ resulted in predictable cell growth, viability and titer changes, which were in good agreement to data from the conventional larger scale bioreactors. ambr™ was found to successfully reproduce variations in temperature, dissolved oxygen (DO), and pH conditions similar to the larger bioreactor systems. Additionally, the miniature bioreactors were found to react well to perturbations in pH and DO through adjustments to the Proportional and Integral control loop. The data presented here demonstrates the utility of the ambr™ system as a high throughput system for cell culture process development. © 2014 American Institute of Chemical Engineers.

  3. Define of internal recirculation coefficient for biological wastewater treatment in anoxic and aerobic bioreactors

    NASA Astrophysics Data System (ADS)

    Rossinskyi, Volodymyr

    2018-02-01

    The biological wastewater treatment technologies in anoxic and aerobic bioreactors with recycle of sludge mixture are used for the effective removal of organic compounds from wastewater. The change rate of sludge mixture recirculation between bioreactors leads to a change and redistribution of concentrations of organic compounds in sludge mixture in bioreactors and change hydrodynamic regimes in bioreactors. Determination of the coefficient of internal recirculation of sludge mixture between bioreactors is important for the choice of technological parameters of biological treatment (wastewater treatment duration in anoxic and aerobic bioreactors, flow capacity of recirculation pumps). Determination of the coefficient of internal recirculation of sludge mixture requires integrated consideration of hydrodynamic parameter (flow rate), kinetic parameter (rate of oxidation of organic compounds) and physical-chemical parameter of wastewater (concentration of organic compounds). The conducted numerical experiment from the proposed mathematical equations allowed to obtain analytical dependences of the coefficient of internal recirculation sludge mixture between bioreactors on the concentration of organic compounds in wastewater, the duration of wastewater treatment in bioreactors.

  4. Differentiation of mammalian skeletal muscle cells cultured on microcarrier beads in a rotating cell culture system

    NASA Technical Reports Server (NTRS)

    Torgan, C. E.; Burge, S. S.; Collinsworth, A. M.; Truskey, G. A.; Kraus, W. E.

    2000-01-01

    The growth and repair of adult skeletal muscle are due in part to activation of muscle precursor cells, commonly known as satellite cells or myoblasts. These cells are responsive to a variety of environmental cues, including mechanical stimuli. The overall goal of the research is to examine the role of mechanical signalling mechanisms in muscle growth and plasticity through utilisation of cell culture systems where other potential signalling pathways (i.e. chemical and electrical stimuli) are controlled. To explore the effects of decreased mechanical loading on muscle differentiation, mammalian myoblasts are cultured in a bioreactor (rotating cell culture system), a model that has been utilised to simulate microgravity. C2C12 murine myoblasts are cultured on microcarrier beads in a bioreactor and followed throughout differentiation as they form a network of multinucleated myotubes. In comparison with three-dimensional control cultures that consist of myoblasts cultured on microcarrier beads in teflon bags, myoblasts cultured in the bioreactor exhibit an attenuation in differentiation. This is demonstrated by reduced immunohistochemical staining for myogenin and alpha-actinin. Western analysis shows a decrease, in bioreactor cultures compared with control cultures, in levels of the contractile proteins myosin (47% decrease, p < 0.01) and tropomyosin (63% decrease, p < 0.01). Hydrodynamic measurements indicate that the decrease in differentiation may be due, at least in part, to fluid stresses acting on the myotubes. In addition, constraints on aggregate size imposed by the action of fluid forces in the bioreactor affect differentiation. These results may have implications for muscle growth and repair during spaceflight.

  5. Design of a novel bioreactor and application in vascular tissue engineering

    NASA Astrophysics Data System (ADS)

    Zhang, Zhi-Xiong; Xi, Ting-Fei; Wang, Ying-Jun; Chen, Xiao-Song; Zhang, Jian; Wang, Chun-Ren; Gu, Yong-Quan; Chen, Liang; Li, Jian-Xin; Chen, Bing

    2008-11-01

    Endothelial cells (ECs) detachment under high shear stress at the early period of transplantation resulted in thrombosis and occlusion. To solve this problem, we developed a novel bioreactor. The bioreactor mimicked the formation of pulsatile flow in physiological conditions. Human umbilical vein ECs were seeded onto the lumen of living tissue conduits grown within dog peritoneal cavity. The shear stress generated by the bioreactor was increased step by step from 1.5 ± 0.8 dyn/cm 2 to 5.3 ± 2.4 dyn/cm 2, and was applied to ECs after static culture for 2 days. The results showed that completely confluent monolayer ECs were elongated, and were oriented parallel to the flow direction. The bioreactor could provide good environment for formation of endothelium. Stepwise increase shear stress could strengthen cell-cell and cell-extracellular matrix. The flow conditions of the bioreactor play a key role to determine the quality of the ECs lining.

  6. Vibration due to non-circularity of a rotating ring having discrete radial supports - With application to thin-walled rotor/magnetic bearing systems

    NASA Astrophysics Data System (ADS)

    Fakkaew, Wichaphon; Cole, Matthew O. T.

    2018-06-01

    This paper investigates the vibration arising in a thin-walled cylindrical rotor subject to small non-circularity and coupled to discrete space-fixed radial bearing supports. A Fourier series description of rotor non-circularity is incorporated within a mathematical model for vibration of a rotating annulus. This model predicts the multi-harmonic excitation of the rotor wall due to bearing interactions. For each non-circularity harmonic there is a set of distinct critical speeds at which resonance can potentially arise due to flexural mode excitation within the rotor wall. It is shown that whether each potential resonance occurs depends on the multiplicity and symmetry of the bearing supports. Also, a sufficient number of evenly spaced identical supports will eliminate low order resonances. The considered problem is pertinent to the design and operation of thin-walled rotors with active magnetic bearing (AMB) supports, for which small clearances exist between the rotor and bearing and so vibration excitation must be limited to avoid contacts. With this motivation, the mathematical model is further developed for the case of a distributed array of electromagnetic actuators controlled by feedback of measured rotor wall displacements. A case study involving an experimental system with short cylindrical rotor and a single radial AMB support is presented. The results show that flexural mode resonance is largely avoided for the considered design topology. Moreover, numerical predictions based on measured non-circularity show good agreement with measurements of rotor wall vibration, thereby confirming the validity and utility of the theoretical model.

  7. Influences of rotation and thermophoresis on MHD peristaltic transport of Jeffrey fluid with convective conditions and wall properties

    NASA Astrophysics Data System (ADS)

    Hayat, T.; Rafiq, M.; Ahmad, B.

    2016-07-01

    This article aims to predict the effects of convective condition and particle deposition on peristaltic transport of Jeffrey fluid in a channel. The whole system is in a rotating frame of reference. The walls of channel are taken flexible. The fluid is electrically conducting in the presence of uniform magnetic field. Non-uniform heat source/sink parameter is also considered. Mass transfer with chemical reaction is considered. Relevant equations for the problems under consideration are first modeled and then simplified using lubrication approach. Resulting equations for stream function and temperature are solved exactly whereas mass transfer equation is solved numerically. Impacts of various involved parameters appearing in the solutions are carefully analyzed.

  8. Pyrosequence analysis of bacterial communities in aerobic bioreactors treating polycyclic aromatic hydrocarbon-contaminated soil

    PubMed Central

    Richardson, Stephen D.; Aitken, Michael D.

    2011-01-01

    Two aerobic, lab-scale, slurry-phase bioreactors were used to examine the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil and the associated bacterial communities. The two bioreactors were operated under semi-continuous (draw-and-fill) conditions at a residence time of 35 days, but one was fed weekly and the other monthly. Most of the quantified PAHs, including high-molecular-weight compounds, were removed to a greater extent in the weekly-fed bioreactor, which achieved total PAH removal of 76%. Molecular analyses, including pyrosequencing of 16S rRNA genes, revealed significant shifts in the soil bacterial communities after introduction to the bioreactors and differences in the abundance and types of bacteria in each of the bioreactors. The weekly-fed bioreactor displayed a more stable bacterial community with gradual changes over time, whereas the monthly-fed bioreactor community was less consistent and may have been more strongly influenced by the influx of untreated soil during feeding. Phylogenetic groups containing known PAH-degrading bacteria previously identified through stable-isotope probing of the untreated soil were differentially affected by bioreactor conditions. Sequences from members of the Acidovorax and Sphingomonas genera, as well as the uncultivated ‘‘Pyrene Group 2’’ were abundant in the bioreactors. However, the relative abundances of sequences from the Pseudomonas, Sphingobium, and Pseudoxanthomonas genera, as well as from a group of unclassified anthracene degraders, were much lower in the bioreactors compared to the untreated soil. PMID:21369833

  9. A versatile miniature bioreactor and its application to bioelectrochemistry studies.

    PubMed

    Kloke, A; Rubenwolf, S; Bücking, C; Gescher, J; Kerzenmacher, S; Zengerle, R; von Stetten, F

    2010-08-15

    Often, reproducible investigations on bio-microsystems essentially require a flexible but well-defined experimental setup, which in its features corresponds to a bioreactor. We therefore developed a miniature bioreactor with a volume in the range of a few millilitre that is assembled by alternate stacking of individual polycarbonate elements and silicone gaskets. All the necessary supply pipes are incorporated as bore holes or cavities within the individual elements. Their combination allows for a bioreactor assembly that is easily adaptable in size and functionality to experimental demands. It allows for controlling oxygen transfer as well as the monitoring of dissolved oxygen concentration and pH-value. The system provides access for media exchange or sterile sampling. A mass transfer coefficient for oxygen (k(L)a) of 4.3x10(-3) s(-1) at a flow rate of only 15 ml min(-1) and a mixing time of 1.5s at a flow rate of 11 ml min(-1) were observed for the modular bioreactor. Single reactor chambers can be interconnected via ion-conductive membranes to form a two-chamber test setup for investigations on electrochemical systems such as fuel cells or sensors. The versatile applicability of this modular and flexible bioreactor was demonstrated by recording a growth curve of Escherichia coli (including monitoring of pH and oxygen) saturation, and also as by two bioelectrochemical experiments. In the first electrochemical experiment the use of the bioreactor enabled a direct comparison of electrode materials for a laccase-catalyzed oxygen reduction electrode. In a second experiment, the bioreactor was utilized to characterize the influence of outer membrane cytochromes on the performance of Shewanella oneidensis in a microbial fuel cell. Copyright 2010 Elsevier B.V. All rights reserved.

  10. Gravitational Effects on Signal Transduction

    NASA Technical Reports Server (NTRS)

    Sytkowski, Arthur J.

    1999-01-01

    An understanding of the mechanisms by which individual cells perceive gravity and how these cells transduce and respond to gravitational stimuli is critical for the development of long-term manned space flight experiments. We now propose to use a well-characterized model erythroid cell system and to investigate gravitational perturbations of its erythropoietin (Epo) signaling pathway and gene regulation. Cells will be grown at 1-G and in simulated microgravity in the NASA Rotating Wall Vessel bioreactor (RWV). Cell growth and differentiation, the Epo-receptor, the protein kinase C pathway to the c-myc gene, and the protein phosphatase pathway to the c-myb gene will be studied and evaluated as reporters of gravitational stimuli. The results of these experiments will have impact on the problems of 1) gravitational sensing by individual cells, and 2) the anemia of space flight. This ground-based study also will serve as a Space Station Development Study in gravitational effects on intracellular signal transduction.

  11. Rotating Juno for Integrating Instruments

    NASA Image and Video Library

    2010-07-12

    Once the radiation vault was installed on top of the propulsion module, NASA Juno spacecraft was lifted onto a large rotation fixture. The fixture allows the spacecraft to be turned for convenient access for integrating and testing instruments.

  12. LEACHATE NITROGEN CONCENTRATIONS AND BACTERIAL NUMBERS FROM TWO BIOREACTOR LANDFILLS

    EPA Science Inventory

    The U.S. EPA and Waste Management Inc. have entered into a cooperative research and development agreement (CRADA) to study landfills operated as bioreactors. Two different landfill bioreactor configurations are currently being tested at the Outer Loop landfill in Louisville, KY...

  13. Wall Shear Stress, Wall Pressure and Near Wall Velocity Field Relationships in a Whirling Annular Seal

    NASA Technical Reports Server (NTRS)

    Morrison, Gerald L.; Winslow, Robert B.; Thames, H. Davis, III

    1996-01-01

    The mean and phase averaged pressure and wall shear stress distributions were measured on the stator wall of a 50% eccentric annular seal which was whirling in a circular orbit at the same speed as the shaft rotation. The shear stresses were measured using flush mounted hot-film probes. Four different operating conditions were considered consisting of Reynolds numbers of 12,000 and 24,000 and Taylor numbers of 3,300 and 6,600. At each of the operating conditions the axial distribution (from Z/L = -0.2 to 1.2) of the mean pressure, shear stress magnitude, and shear stress direction on the stator wall were measured. Also measured were the phase averaged pressure and shear stress. These data were combined to calculate the force distributions along the seal length. Integration of the force distributions result in the net forces and moments generated by the pressure and shear stresses. The flow field inside the seal operating at a Reynolds number of 24,000 and a Taylor number of 6,600 has been measured using a 3-D laser Doppler anemometer system. Phase averaged wall pressure and wall shear stress are presented along with phase averaged mean velocity and turbulence kinetic energy distributions located 0.16c from the stator wall where c is the seal clearance. The relationships between the velocity, turbulence, wall pressure and wall shear stress are very complex and do not follow simple bulk flow predictions.

  14. NASAs B377SGT Super Guppy Turbine Cargo Airplane lands at Moffett Field at NASA Ames.

    NASA Image and Video Library

    2016-01-25

    NASA N941NA Superguppy at Moffett Field. Cargo is loaded into the Super Guppy when the aircraft's "fold-away" nose rotates 110 degrees to the left, allowing unobstructed access to the 25 foot diameter fuselage.

  15. Use of the Ames Check Standard Model for the Validation of Wall Interference Corrections

    NASA Technical Reports Server (NTRS)

    Ulbrich, N.; Amaya, M.; Flach, R.

    2018-01-01

    The new check standard model of the NASA Ames 11-ft Transonic Wind Tunnel was chosen for a future validation of the facility's wall interference correction system. The chosen validation approach takes advantage of the fact that test conditions experienced by a large model in the slotted part of the tunnel's test section will change significantly if a subset of the slots is temporarily sealed. Therefore, the model's aerodynamic coefficients have to be recorded, corrected, and compared for two different test section configurations in order to perform the validation. Test section configurations with highly accurate Mach number and dynamic pressure calibrations were selected for the validation. First, the model is tested with all test section slots in open configuration while keeping the model's center of rotation on the tunnel centerline. In the next step, slots on the test section floor are sealed and the model is moved to a new center of rotation that is 33 inches below the tunnel centerline. Then, the original angle of attack sweeps are repeated. Afterwards, wall interference corrections are applied to both test data sets and response surface models of the resulting aerodynamic coefficients in interference-free flow are generated. Finally, the response surface models are used to predict the aerodynamic coefficients for a family of angles of attack while keeping dynamic pressure, Mach number, and Reynolds number constant. The validation is considered successful if the corrected aerodynamic coefficients obtained from the related response surface model pair show good agreement. Residual differences between the corrected coefficient sets will be analyzed as well because they are an indicator of the overall accuracy of the facility's wall interference correction process.

  16. A novel continuous two-phase partitioning bioreactor operated with polymeric tubing: Performance validation for enhanced biological removal of toxic substrates.

    PubMed

    Tomei, M Concetta; Mosca Angelucci, Domenica; Daugulis, Andrew J

    2017-02-01

    A continuous two-phase partitioning bioreactor (C-TPPB), operated with coiled tubing made of the DuPont polymer Hytrel 8206, was tested for the bioremediation of 4-chlorophenol, as a model toxic compound. The tubing was immersed in the aqueous phase, with the contaminated water flowing tube-side, and an adapted microbial culture suspended in the bioreactor itself, with the metabolic demand of the cells creating a concentration gradient to cause the substrate to diffuse into the bioreactor for biodegradation. The system was operated over a range of loadings (tubing influent concentration 750-1500 mg L -1 ), with near-complete substrate removal in all cases. Distribution of the contaminant at the end of the tests (96 h) highlighted biological removal in the range of 87-95%, while the amount retained in the polymer ranged from ∼1 to 8%. Mass transfer of the substrate across the tubing wall was not limiting, and the polymer demonstrated the capacity to buffer the substrate loadings and to adapt to microbial metabolism. The impact of C-TPPB operation on biomass activity was also investigated by a kinetic characterization of the microbial culture, which showed better resistance to substrate inhibition after C-TPPB operation, thereby confirming the beneficial effect of sub-inhibitory controlled conditions, characteristic of TPPB systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Rotating Globe of Ganymede Geology

    NASA Image and Video Library

    2014-02-12

    This is a frame from an animation of a rotating globe of Jupiter moon Ganymede, with a geologic map superimposed over a global color mosaic, incorporating the best available imagery from NASA Voyager 1 and 2 spacecraft, and Galileo spacecraft.

  18. Deformation simulation of cells seeded on a collagen-GAG scaffold in a flow perfusion bioreactor using a sequential 3D CFD-elastostatics model.

    PubMed

    Jungreuthmayer, C; Jaasma, M J; Al-Munajjed, A A; Zanghellini, J; Kelly, D J; O'Brien, F J

    2009-05-01

    Tissue-engineered bone shows promise in meeting the huge demand for bone grafts caused by up to 4 million bone replacement procedures per year, worldwide. State-of-the-art bone tissue engineering strategies use flow perfusion bioreactors to apply biophysical stimuli to cells seeded on scaffolds and to grow tissue suitable for implantation into the patient's body. The aim of this study was to quantify the deformation of cells seeded on a collagen-GAG scaffold which was perfused by culture medium inside a flow perfusion bioreactor. Using a microCT scan of an unseeded collagen-GAG scaffold, a sequential 3D CFD-deformation model was developed. The wall shear stress and the hydrostatic wall pressure acting on the cells were computed through the use of a CFD simulation and fed into a linear elastostatics model in order to calculate the deformation of the cells. The model used numerically seeded cells of two common morphologies where cells are either attached flatly on the scaffold wall or bridging two struts of the scaffold. Our study showed that the displacement of the cells is primarily determined by the cell morphology. Although cells of both attachment profiles were subjected to the same mechanical load, cells bridging two struts experienced a deformation up to 500 times higher than cells only attached to one strut. As the scaffold's pore size determines both the mechanical load and the type of attachment, the design of an optimal scaffold must take into account the interplay of these two features and requires a design process that optimizes both parameters at the same time.

  19. Protein Expression in Insect and Mammalian Cells Using Baculoviruses in Wave Bioreactors.

    PubMed

    Kadwell, Sue H; Overton, Laurie K

    2016-01-01

    Many types of disposable bioreactors for protein expression in insect and mammalian cells are now available. They differ in design, capacity, and sensor options, with many selections available for either rocking platform, orbitally shaken, pneumatically mixed, or stirred-tank bioreactors lined with an integral disposable bag (Shukla and Gottschalk, Trends Biotechnol 31(3):147-154, 2013). WAVE Bioreactors™ were among the first disposable systems to be developed (Singh, Cytotechnology 30:149-158, 1999). Since their commercialization in 1999, Wave Bioreactors have become routinely used in many laboratories due to their ease of operation, limited utility requirements, and protein expression levels comparability to traditional stirred-tank bioreactors. Wave Bioreactors are designed to use a presterilized Cellbag™, which is attached to a rocking platform and inflated with filtered air provided by the bioreactor unit. The Cellbag can be filled with medium and cells and maintained at a set temperature. The rocking motion, which is adjusted through angle and rock speed settings, provides mixing of oxygen (and CO2, which is used to control pH in mammalian cell cultures) from the headspace created in the inflated Cellbag with the cell culture medium and cells. This rocking motion can be adjusted to prevent cell shear damage. Dissolved oxygen and pH can be monitored during scale-up, and samples can be easily removed to monitor other parameters. Insect and mammalian cells grow very well in Wave Bioreactors (Shukla and Gottschalk, Trends Biotechnol 31(3):147-154, 2013). Combining Wave Bioreactor cell growth capabilities with recombinant baculoviruses engineered for insect or mammalian cell expression has proven to be a powerful tool for rapid production of a wide range of proteins.

  20. Bioreactors for removing methyl bromide following contained fumigations

    USGS Publications Warehouse

    Miller, L.G.; Baesman, S.M.; Oremland, R.S.

    2003-01-01

    Use of methyl bromide (MeBr) as a quarantine, commodity, or structural fumigant is under scrutiny because its release to the atmosphere contributes to the depletion of stratospheric ozone. A closed-system bioreactor consisting of 0.5 L of a growing culture of a previously described bacterium, strain IMB-1, removed MeBr (> 110 ??mol L-1) from recirculating air. Strain IMB-1 grew slowly to high cell densities in the bioreactor using MeBr as its sole carbon and energy source. Bacterial oxidation of MeBr produced CO2 and hydrobromic acid (HBr), which required continuous neutralization with NaOH for the system to operate effectively. Strain IMB-1 was capable of sustained oxidation of large amounts of MeBr (170 mmol in 46 d). In an open-system bioreactor (10-L fermenter), strain IMB-1 oxidized a continuous supply of MeBr (220 ??mol L-1 in air). Growth was continuous, and 0.5 mol of MeBr was removed from the air supply in 14 d. The specific rate of MeBr oxidation was 7 ?? 10-16 mol cell-1 h-1. Bioreactors such as these can therefore be used to remove large quantities of contaminant MeBr, which opens the possibility of biodegradation as a practical means for its disposal.

  1. Aggregation of Culture Expanded Human Mesenchymal Stem Cells in Microcarrier-based Bioreactor.

    PubMed

    Yuan, Xuegang; Tsai, Ang-Chen; Farrance, Iain; Rowley, Jon; Ma, Teng

    2018-03-15

    Three-dimensional aggregation of human mesenchymal stem cells (hMSCs) has been used to enhance their therapeutic properties but current fabrication protocols depend on laboratory methods and are not scalable. In this study, we developed thermal responsive poly(N-isopropylacrylamide) grafted microcarriers (PNIPAM-MCs), which supported expansion and thermal detachment of hMSCs at reduced temperature (23.0 °C). hMSCs were cultured on the PNIPAM-MCs in both spinner flask (SF) and PBS Vertical-Wheel (PBS-VW) bioreactors for expansion. At room temperature, hMSCs were detached as small cell sheets, which subsequently self-assembled into 3D hMSC aggregates in PBS-VW bioreactor and remain as single cells in SF bioreactor owing to different hydrodynamic conditions. hMSC aggregates generated from the bioreactor maintained comparable immunomodulation and cytokine secretion properties compared to the ones made from the AggreWell ® . The results of the current study demonstrate the feasibility of scale-up production of hMSC aggregates in the suspension bioreactor using thermal responsive microcarriers for integrated cell expansion and 3D aggregation in a close bioreactor system and highlight the critical role of hydrodynamics in self-assembly of detached hMSC in suspension.

  2. NASA Thesaurus Supplement: A Three-Part Cumulative Update of the 1998 Edition of the NASA Thesaurus. Supplement 4

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The NASA Thesaurus Supplement is a cumulative update to the 1998 edition of the NASA Thesaurus (NASA/SP-1998-7501). The Supplement, published every six months, includes all new terms and associated hierarchies added since the cutoff for the 1998 edition (December 1997). Parts 1 and 2 (Hierarchical Listing and Rotated Term Display) correspond to Volumes 1 and 2 of the 1998 printed edition. Definitions are included in Part 1; uppercase/lowercase forms are provided in both Parts 1 and 2. Part 3 is a list of deletions or changes to valid terms.

  3. NASAs B377SGT Super Guppy Turbine Cargo Airplane lands at Moffett Field at NASA Ames.

    NASA Image and Video Library

    2016-01-08

    NASA N941NA Superguppy lands at the Moffett Field. Cargo is loaded into the Super Guppy when the aircraft's "fold-away" nose rotates 110 degrees to the left, allowing unobstructed access to the 25 foot diameter fuselage.

  4. In-situ Raman microprobe studies of plant cell walls: macromolecular organization and compositional variability in the secondary wall of Picea mariana (Mill.) B.S.P.

    Treesearch

    U.P. Agarwal; R.H. Atalla

    1986-01-01

    Native-state organization and distribution of cell-wall components in the secondary wall of woody tissue from P. mariana (Black Spruce) have been investigated using polarized Raman microspectroscopy. Evidence for orientation is detected through Raman intensity variations resulting from rotations of the exciting electric vector with respect to cell-wall geometry....

  5. COMPUTER SIMULATOR (BEST) FOR DESIGNING SULFATE-REDUCING BACTERIA FIELD BIOREACTORS

    EPA Science Inventory

    BEST (bioreactor economics, size and time of operation) is a spreadsheet-based model that is used in conjunction with public domain software, PhreeqcI. BEST is used in the design process of sulfate-reducing bacteria (SRB) field bioreactors to passively treat acid mine drainage (A...

  6. DESIGNING SULFATE-REDUCING BACTERIA FIELD BIOREACTORS USING THE BEST MODEL

    EPA Science Inventory

    BEST (bioreactor economics, size and time of operation) is a spreadsheet-based model that is used in conjunction with a public domain computer software package, PHREEQCI. BEST is intended to be used in the design process of sulfate-reducing bacteria (SRB)field bioreactors to pas...

  7. Evidence for using Monte Carlo calculated wall attenuation and scatter correction factors for three styles of graphite-walled ion chamber.

    PubMed

    McCaffrey, J P; Mainegra-Hing, E; Kawrakow, I; Shortt, K R; Rogers, D W O

    2004-06-21

    The basic equation for establishing a 60Co air-kerma standard based on a cavity ionization chamber includes a wall correction term that corrects for the attenuation and scatter of photons in the chamber wall. For over a decade, the validity of the wall correction terms determined by extrapolation methods (K(w)K(cep)) has been strongly challenged by Monte Carlo (MC) calculation methods (K(wall)). Using the linear extrapolation method with experimental data, K(w)K(cep) was determined in this study for three different styles of primary-standard-grade graphite ionization chamber: cylindrical, spherical and plane-parallel. For measurements taken with the same 60Co source, the air-kerma rates for these three chambers, determined using extrapolated K(w)K(cep) values, differed by up to 2%. The MC code 'EGSnrc' was used to calculate the values of K(wall) for these three chambers. Use of the calculated K(wall) values gave air-kerma rates that agreed within 0.3%. The accuracy of this code was affirmed by its reliability in modelling the complex structure of the response curve obtained by rotation of the non-rotationally symmetric plane-parallel chamber. These results demonstrate that the linear extrapolation technique leads to errors in the determination of air-kerma.

  8. Comparison of a two-dimensional adaptive-wall technique with analytical wall interference correction techniques

    NASA Technical Reports Server (NTRS)

    Mineck, Raymond E.

    1992-01-01

    A two dimensional airfoil model was tested in the adaptive wall test section of the NASA Langley 0.3 meter Transonic Cryogenic Tunnel (TCT) and in the ventilated test section of the National Aeronautical Establishment Two Dimensional High Reynold Number Facility (HRNF). The primary goal of the tests was to compare different techniques (adaptive test section walls and classical, analytical corrections) to account for wall interference. Tests were conducted over a Mach number range from 0.3 to 0.8 at chord Reynolds numbers of 10 x 10(exp 6), 15 x 10(exp 6), and 20 x 10(exp 6). The angle of attack was varied from about 12 degrees up to stall. Movement of the top and bottom test section walls was used to account for the wall interference in the HRNF tests. The test results are in good agreement.

  9. A Flow Perfusion Bioreactor System for Vocal Fold Tissue Engineering Applications

    PubMed Central

    Heris, Hossein K.; Thomson, Scott L.; Taher, Rani; Kazemirad, Siavash; Sheibani, Sara; Li-Jessen, Nicole Y.K.; Vali, Hojatollah; Mongeau, Luc

    2016-01-01

    The human vocal folds (VFs) undergo complex biomechanical stimulation during phonation. The aim of the present study was to develop and validate a phono-mimetic VF flow perfusion bioreactor, which mimics the mechanical microenvironment of the human VFs in vitro. The bioreactor uses airflow-induced self-oscillations, which have been shown to produce mechanical loading and contact forces that are representative of human phonation. The bioreactor consisted of two synthetic VF replicas within a silicone body. A cell-scaffold mixture (CSM) consisting of human VF fibroblasts, hyaluronic acid, gelatin, and a polyethylene glycol cross-linker was injected into cavities within the replicas. Cell culture medium (CCM) was perfused through the scaffold by using a customized secondary flow loop. After the injection, the bioreactor was operated with no stimulation over a 3-day period to allow for cell adaptation. Phonation was subsequently induced by using a variable speed centrifugal blower for 2 h each day over a period of 4 days. A similar bioreactor without biomechanical stimulation was used as the nonphonatory control. The CSM was harvested from both VF replicas 7 days after the injection. The results confirmed that the phono-mimetic bioreactor supports cell viability and extracellular matrix proteins synthesis, as expected. Many scaffold materials were found to degrade because of challenges from phonation-induced biomechanical stimulation as well as due to biochemical reactions with the CCM. The bioreactor concept enables future investigations of the effects of different phonatory characteristics, that is, voice regimes, on the behavior of the human VF cells. It will also help study the long-term functional outcomes of the VF-specific biomaterials before animal and clinical studies. PMID:27537192

  10. A Flow Perfusion Bioreactor System for Vocal Fold Tissue Engineering Applications.

    PubMed

    Latifi, Neda; Heris, Hossein K; Thomson, Scott L; Taher, Rani; Kazemirad, Siavash; Sheibani, Sara; Li-Jessen, Nicole Y K; Vali, Hojatollah; Mongeau, Luc

    2016-09-01

    The human vocal folds (VFs) undergo complex biomechanical stimulation during phonation. The aim of the present study was to develop and validate a phono-mimetic VF flow perfusion bioreactor, which mimics the mechanical microenvironment of the human VFs in vitro. The bioreactor uses airflow-induced self-oscillations, which have been shown to produce mechanical loading and contact forces that are representative of human phonation. The bioreactor consisted of two synthetic VF replicas within a silicone body. A cell-scaffold mixture (CSM) consisting of human VF fibroblasts, hyaluronic acid, gelatin, and a polyethylene glycol cross-linker was injected into cavities within the replicas. Cell culture medium (CCM) was perfused through the scaffold by using a customized secondary flow loop. After the injection, the bioreactor was operated with no stimulation over a 3-day period to allow for cell adaptation. Phonation was subsequently induced by using a variable speed centrifugal blower for 2 h each day over a period of 4 days. A similar bioreactor without biomechanical stimulation was used as the nonphonatory control. The CSM was harvested from both VF replicas 7 days after the injection. The results confirmed that the phono-mimetic bioreactor supports cell viability and extracellular matrix proteins synthesis, as expected. Many scaffold materials were found to degrade because of challenges from phonation-induced biomechanical stimulation as well as due to biochemical reactions with the CCM. The bioreactor concept enables future investigations of the effects of different phonatory characteristics, that is, voice regimes, on the behavior of the human VF cells. It will also help study the long-term functional outcomes of the VF-specific biomaterials before animal and clinical studies.

  11. Hydrodynamic performance of a single-use aerated stirred bioreactor in animal cell culture: applications of tomography, dynamic gas disengagement (DGD), and CFD.

    PubMed

    Kazemzadeh, Argang; Elias, Cynthia; Tamer, Melih; Ein-Mozaffari, Farhad

    2018-05-01

    The hydrodynamics of gas-liquid two-phase flow in a single-use bioreactor were investigated in detail both experimentally and numerically. Electrical resistance tomography (ERT) and dynamic gas disengagement (DGD) combined with computational fluid dynamics (CFD) were employed to assess the effect of the volumetric gas flow rate and impeller speed on the gas-liquid flow field, local and global gas holdup values, and Sauter mean bubble diameter. From the results obtained from DGD coupled with ERT, the bubble sizes were determined. The experimental data indicated that the total gas holdup values increased with increasing both the rotational speed of impeller and volumetric gas flow rate. Moreover, the analysis of the flow field generated inside the aerated stirred bioreactor was conducted using CFD results. Overall, a more uniform distribution of the gas holdup was obtained at impeller speeds ≥ 100 rpm for volumetric gas flow rates ≥ 1.6 × 10 -5  m 3 /s.

  12. Effects of aeration frequency on leachate quality and waste in simulated hybrid bioreactor landfills.

    PubMed

    Ko, Jae Hac; Ma, Zeyu; Jin, Xiao; Xu, Qiyong

    2016-12-01

    Research has been conducted to investigate the effects of daily aeration frequency on leachate quality and waste settlement in simulated hybrid landfill bioreactors. Four laboratory-scale reactors were constructed and operated for about 10 months to simulate different bioreactor operations, including one anaerobic bioreactor and three hybrid bioreactors with different aeration frequencies (one, two, and four times per day). Chemical oxygen demand (COD) and biochemical oxygen demand (BOD 5 ) reduced more than 96% of the initial concentrations in all aerated bioreactors. The differences of COD and BOD 5 reductions among tested aeration frequencies were relatively small. For ammonia nitrogen, the higher aeration frequency (two or four times per day) resulted in the quicker reduction. Overall, the concentrations of heavy metals (Cr, Co, Cu, Mn, Ni, and Zn) decreased over time except Cd and Pb. The reduction of redox-sensitive metal concentrations (Mn, Co, Ni, and Cu) was greater in aerated bioreactors than in anaerobic bioreactor. Settlement of municipal solid waste (MSW) was enhanced with higher frequency of aeration events (four times per day). In recent years, hybird bioreactor landfill technology has gained a lot of attention. Appropriate aeration rate is crucial for hybrid bioreactor operation, but few studies have been done and different results were obtained. Research was conducted to investigate the effects of daily aeration frequency on leachate quality and waste settlement. Results indicated that aeration can effectively accelerate waste stabilization and remove organic carbon concentration and total nitrogen in the leachate.

  13. Membrane bioreactors for the removal of anionic micropollutants from drinking water.

    PubMed

    Crespo, João G; Velizarov, Svetlozar; Reis, Maria A

    2004-10-01

    Biological treatment processes allow for the effective elimination of anionic micropollutants from drinking water. However, special technologies have to be implemented to eliminate the target pollutants without changing water quality, either by adding new pollutants or removing essential water components. Some innovative technologies that combine the use of membranes with the biological degradation of ionic micropollutants in order to minimize the secondary contamination of treated water include pressure-driven membrane bioreactors, gas-transfer membrane bioreactors and ion exchange membrane bioreactors.

  14. Gender differences in passive knee biomechanical properties in tibial rotation.

    PubMed

    Park, Hyung-Soon; Wilson, Nicole A; Zhang, Li-Qun

    2008-07-01

    The anterior cruciate ligament (ACL) is the most commonly injured knee ligament with the highest incidence of injury in female athletes who participate in pivoting sports. Noncontact ACL injuries commonly occur with both internal and external tibial rotation. ACL impingement against the lateral wall of the intercondylar notch during tibial external rotation and abduction has been proposed as an injury mechanism, but few studies have evaluated in vivo gender-specific differences in laxity and stiffness in external and internal tibial rotations. The purpose of this study was to evaluate these differences. The knees of 10 male and 10 female healthy subjects were rotated between internal and external tibial rotation with the knee at 60 degrees of flexion. Joint laxity, stiffness, and energy loss were compared between male and female subjects. Women had higher laxity (p = 0.01), lower stiffness (p = 0.038), and higher energy loss (p = 0.008) in external tibial rotation than did men. The results suggest that women may be at greater risk of ACL injury resulting from impingement against the lateral wall of the intercondylar notch, which has been shown to be associated with external tibial rotation and abduction.

  15. A simple eccentric stirred tank mini-bioreactor: mixing characterization and mammalian cell culture experiments.

    PubMed

    Bulnes-Abundis, David; Carrillo-Cocom, Leydi M; Aráiz-Hernández, Diana; García-Ulloa, Alfonso; Granados-Pastor, Marisa; Sánchez-Arreola, Pamela B; Murugappan, Gayathree; Alvarez, Mario M

    2013-04-01

    In industrial practice, stirred tank bioreactors are the most common mammalian cell culture platform. However, research and screening protocols at the laboratory scale (i.e., 5-100 mL) rely primarily on Petri dishes, culture bottles, or Erlenmeyer flasks. There is a clear need for simple-easy to assemble, easy to use, easy to clean-cell culture mini-bioreactors for lab-scale and/or screening applications. Here, we study the mixing performance and culture adequacy of a 30 mL eccentric stirred tank mini-bioreactor. A detailed mixing characterization of the proposed bioreactor is presented. Laser induced fluorescence (LIF) experiments and computational fluid dynamics (CFD) computations are used to identify the operational conditions required for adequate mixing. Mammalian cell culture experiments were conducted with two different cell models. The specific growth rate and the maximum cell density of Chinese hamster ovary (CHO) cell cultures grown in the mini-bioreactor were comparable to those observed for 6-well culture plates, Erlenmeyer flasks, and 1 L fully instrumented bioreactors. Human hematopoietic stem cells were successfully expanded tenfold in suspension conditions using the eccentric mini-bioreactor system. Our results demonstrate good mixing performance and suggest the practicality and adequacy of the proposed mini-bioreactor. Copyright © 2012 Wiley Periodicals, Inc.

  16. TRACING INFALL AND ROTATION ALONG THE OUTFLOW CAVITY WALLS OF THE L483 PROTOSTELLAR ENVELOPE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leung, Gigi Y.C.; Lim, Jeremy; Takakuwa, Shigehisa

    2016-12-10

    Single-dish observations in CS(7–6) reveal emission extending out to thousands of au along the outflow axis of low-mass protostars and having a velocity gradient in the opposite direction to that of their outflows. This emission has been attributed to dense and warm gas flowing outward along the walls of bipolar outflow cavities. Here, we present combined single-dish and interferometric CS(7–6) maps for the low-mass protostar L483, revealing a newly discovered compact central component (radius ≲800 au) and previously unknown features in its extended component (visible out to ∼4000 au). The velocity gradient and skewed (toward the redshifted side) brightness distributionmore » of the extended component are detectable out to a radius of ∼2000 au, but not beyond. The compact central component exhibits a velocity gradient in the same direction as, but which is steeper than that of, the extended component. Furthermore, both components exhibit a velocity gradient with an approximately constant magnitude across the outflow axis, apparent in the extended component not just through but also away from the center out to 2000 au. We point out contradictions between our results and model predictions for outflowing gas and propose a new model in which all of the aforementioned emission can be qualitatively explained by gas inflowing along the outflow cavity walls of a rigidly rotating envelope. Our model also can explain the extended CS(7–6) emission observed around other low-mass protostars.« less

  17. Development and Characterization of a Parallelizable Perfusion Bioreactor for 3D Cell Culture.

    PubMed

    Egger, Dominik; Fischer, Monica; Clementi, Andreas; Ribitsch, Volker; Hansmann, Jan; Kasper, Cornelia

    2017-05-25

    The three dimensional (3D) cultivation of stem cells in dynamic bioreactor systems is essential in the context of regenerative medicine. Still, there is a lack of bioreactor systems that allow the cultivation of multiple independent samples under different conditions while ensuring comprehensive control over the mechanical environment. Therefore, we developed a miniaturized, parallelizable perfusion bioreactor system with two different bioreactor chambers. Pressure sensors were also implemented to determine the permeability of biomaterials which allows us to approximate the shear stress conditions. To characterize the flow velocity and shear stress profile of a porous scaffold in both bioreactor chambers, a computational fluid dynamics analysis was performed. Furthermore, the mixing behavior was characterized by acquisition of the residence time distributions. Finally, the effects of the different flow and shear stress profiles of the bioreactor chambers on osteogenic differentiation of human mesenchymal stem cells were evaluated in a proof of concept study. In conclusion, the data from computational fluid dynamics and shear stress calculations were found to be predictable for relative comparison of the bioreactor geometries, but not for final determination of the optimal flow rate. However, we suggest that the system is beneficial for parallel dynamic cultivation of multiple samples for 3D cell culture processes.

  18. Development and Characterization of a Parallelizable Perfusion Bioreactor for 3D Cell Culture

    PubMed Central

    Egger, Dominik; Fischer, Monica; Clementi, Andreas; Ribitsch, Volker; Hansmann, Jan; Kasper, Cornelia

    2017-01-01

    The three dimensional (3D) cultivation of stem cells in dynamic bioreactor systems is essential in the context of regenerative medicine. Still, there is a lack of bioreactor systems that allow the cultivation of multiple independent samples under different conditions while ensuring comprehensive control over the mechanical environment. Therefore, we developed a miniaturized, parallelizable perfusion bioreactor system with two different bioreactor chambers. Pressure sensors were also implemented to determine the permeability of biomaterials which allows us to approximate the shear stress conditions. To characterize the flow velocity and shear stress profile of a porous scaffold in both bioreactor chambers, a computational fluid dynamics analysis was performed. Furthermore, the mixing behavior was characterized by acquisition of the residence time distributions. Finally, the effects of the different flow and shear stress profiles of the bioreactor chambers on osteogenic differentiation of human mesenchymal stem cells were evaluated in a proof of concept study. In conclusion, the data from computational fluid dynamics and shear stress calculations were found to be predictable for relative comparison of the bioreactor geometries, but not for final determination of the optimal flow rate. However, we suggest that the system is beneficial for parallel dynamic cultivation of multiple samples for 3D cell culture processes. PMID:28952530

  19. Expansion of Human Mesenchymal Stem Cells in a Microcarrier Bioreactor.

    PubMed

    Tsai, Ang-Chen; Ma, Teng

    2016-01-01

    Human mesenchymal stem cells (hMSCs) are considered as a primary candidate in cell therapy owing to their self-renewability, high differentiation capabilities, and secretions of trophic factors. In clinical application, a large quantity of therapeutically competent hMSCs is required that cannot be produced in conventional petri dish culture. Bioreactors are scalable and have the capacity to meet the production demand. Microcarrier suspension culture in stirred-tank bioreactors is the most widely used method to expand anchorage dependent cells in a large scale. Stirred-tank bioreactors have the potential to scale up and microcarriers provide the high surface-volume ratio. As a result, a spinner flask bioreactor with microcarriers has been commonly used in large scale expansion of adherent cells. This chapter describes a detailed culture protocol for hMSC expansion in a 125 mL spinner flask using microcarriers, Cytodex I, and a procedure for cell seeding, expansion, metabolic sampling, and quantification and visualization using microculture tetrazolium (MTT) reagent.

  20. Counter Clockwise Rotation of Cylinder with Variable Position to Control Base Flows

    NASA Astrophysics Data System (ADS)

    Asadullah, Mohammed; Khan, S. A.; Asrar, Waqar; Sulaeman, E.

    2018-05-01

    Experimental study of supersonic base flow at Mach 2 has been carried out to see the effect of cylinder when rotated counter clockwise inside the dead zone at variable locations near its base to control base pressure for different level of expansion for area ratio 9. Active cylinder of 2 mm diameter rotating counter clockwise when seen from top, is mounted as a controller. Three locations are chosen from the side wall of square duct namely at 2, 4, 6 mm respectively and 8 mm from square nozzle exit in the base region to mount the controller. Base pressure in recirculation zone and wall pressure along the square duct length has been measured with and without control. The experiments were carried out for NPR 2, 3, 6, 7.8 and 8.5. Cylinder when rotated counter clockwise as an active controller were found to reduce the base drag as high as 62 percent at NPR 8.5 when located near to duct wall and 50 percent when located away from duct wall for the same NPR. For perfectly expanded flows at NPR 7.8 the reduction in base drag was 53 percent near duct wall and 44 percent near duct wall. The active controller was up to 19 percentage effective for over expanded flows near to duct wall and up to 12 percent when located away from duct wall. Also, the control did not adversely affect the flow field.

  1. Experimental measurement of the orbital paths of particles sedimenting within a rotating viscous fluid as influenced by gravity

    NASA Technical Reports Server (NTRS)

    Wolf, David A.; Schwarz, Ray P.

    1992-01-01

    Measurements were taken of the path of a simulated typical tissue segment or 'particle' within a rotating fluid as a function of gravitational strength, fluid rotation rate, particle sedimentation rate, and particle initial position. Parameters were examined within the useful range for tissue culture in the NASA rotating wall culture vessels. The particle moves along a nearly circular path through the fluid (as observed from the rotating reference frame of the fluid) at the same speed as its linear terminal sedimentation speed for the external gravitational field. This gravitationally induced motion causes an increasing deviation of the particle from its original position within the fluid for a decreased rotational rate, for a more rapidly sedimenting particle, and for an increased gravitational strength. Under low gravity conditions (less than 0.1 G), the particle's motion through the fluid and its deviation from its original position become negligible. Under unit gravity conditions, large distortions (greater than 0.25 inch) occur even for particles of slow sedimentation rate (less than 1.0 cm/sec). The particle's motion is nearly independent of the particle's initial position. Comparison with mathematically predicted particle paths show that a significant error in the mathematically predicted path occurs for large particle deviations. This results from a geometric approximation and numerically accumulating error in the mathematical technique.

  2. [Research progress of in vivo bioreactor as vascularization strategies in bone tissue engineering].

    PubMed

    Zhang, Haifeng; Han, Dong

    2014-09-01

    To review the application and research progress of in vivo bioreactor as vascularization strategies in bone tissue engineering. The original articles about in vivo bioreactor that can enhance vascularization of tissue engineered bone were extensively reviewed and analyzed. The in vivo bioreactor can be created by periosteum, muscle, muscularis membrane, and fascia flap as well as biomaterials. Using in vivo bioreactor can effectively promote the establishment of a microcirculation in the tissue engineered bones, especially for large bone defects. However, main correlative researches, currently, are focused on animal experiments, more clinical trials will be carried out in the future. With the rapid development of related technologies of bone tissue engineering, the use of in vivo bioreactor will to a large extent solve the bottleneck limitations and has the potential values for clinical application.

  3. NASAs B377SGT Super Guppy Turbine Cargo Airplane lands at Moffett Field at NASA Ames.

    NASA Image and Video Library

    2016-01-08

    NASA N941NA parked in front of Hangar 1 at Moffett Field. Cargo is loaded into the Super Guppy when the aircraft's "fold-away" nose rotates 110 degrees to the left, allowing unobstructed access to the 25 foot diameter fuselage.

  4. Seasonal Patterns in Microbial Community Composition in Denitrifying Bioreactors Treating Subsurface Agricultural Drainage.

    PubMed

    Porter, Matthew D; Andrus, J Malia; Bartolerio, Nicholas A; Rodriguez, Luis F; Zhang, Yuanhui; Zilles, Julie L; Kent, Angela D

    2015-10-01

    Denitrifying bioreactors, consisting of water flow control structures and a woodchip-filled trench, are a promising approach for removing nitrate from agricultural subsurface or tile drainage systems. To better understand the seasonal dynamics and the ecological drivers of the microbial communities responsible for denitrification in these bioreactors, we employed microbial community "fingerprinting" techniques in a time-series examination of three denitrifying bioreactors over 2 years, looking at bacteria, fungi, and the denitrifier functional group responsible for the final step of complete denitrification. Our analysis revealed that microbial community composition responds to depth and seasonal variation in moisture content and inundation of the bioreactor media, as well as temperature. Using a geostatistical analysis approach, we observed recurring temporal patterns in bacterial and denitrifying bacterial community composition in these bioreactors, consistent with annual cycling. The fungal communities were more stable, having longer temporal autocorrelations, and did not show significant annual cycling. These results suggest a recurring seasonal cycle in the denitrifying bioreactor microbial community, likely due to seasonal variation in moisture content.

  5. A thick-walled sphere rotating in a uniform magnetic field: The next step to de-spin a space object

    NASA Astrophysics Data System (ADS)

    Nurge, Mark A.; Youngquist, Robert C.; Caracciolo, Ryan A.; Peck, Mason; Leve, Frederick A.

    2017-08-01

    Modeling the interaction between a moving conductor and a static magnetic field is critical to understanding the operation of induction motors, eddy current braking, and the dynamics of satellites moving through Earth's magnetic field. Here, we develop the case of a thick-walled sphere rotating in a uniform magnetic field, which is the simplest, non-trivial, magneto-statics problem that leads to complete closed-form expressions for the resulting potentials, fields, and currents. This solution requires knowledge of all of Maxwell's time independent equations, scalar and vector potential equations, and the Lorentz force law. The paper presents four cases and their associated experimental results, making this topic appropriate for an advanced student lab project.

  6. Helicity fluctuations and turbulent energy production in rotating and non-rotating pipes

    NASA Technical Reports Server (NTRS)

    Orlandi, P.

    1995-01-01

    Finite-difference second-order accurate direct simulation of a turbulent pipe has been used to investigate how the turbulence production and dissipation change when a solid body rotation is applied. It is shown that when the helicity increases, the dissipation is reduced. It is asserted that to have a drag reduction the external action should be such as to disrupt the symmetry of right- and left-handed helical structures. In this study the Navier-Stokes equations in rotational form permit the turbulent energy production to be split into a part related to the energy cascade from large to small scales and into a part related to the convection by large scales. The full simulation data have shown the latter is greater than the former in the wall region and that, on the contrary, these two terms balance each other in the central region. From the pdf of the former, it has been shown how the vortical structures are changed in the wall region by the background radiation and how they are related to the changes in the energy production.

  7. New NASA Images of Irma's Towering Clouds

    NASA Image and Video Library

    2017-09-08

    On Sept. 7, the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite passed over Hurricane Irma at approximately 11:20 a.m. local time. The MISR instrument comprises nine cameras that view the Earth at different angles, and since it takes roughly seven minutes for all nine cameras to capture the same location, the motion of the clouds between images allows scientists to calculate the wind speed at the cloud tops. The animated GIF shows Irma's motion over the seven minutes of the MISR imagery. North is toward the top of the image. This composite image shows Hurricane Irma as viewed by the central, downward-looking camera (left), as well as the wind speeds (right) superimposed on the image. The length of the arrows is proportional to the wind speed, while their color shows the altitude at which the winds were calculated. At the time the image was acquired, Irma's eye was located approximately 60 miles (100 kilometers) north of the Dominican Republic and 140 miles (230 kilometers) north of its capital, Santo Domingo. Irma was a powerful Category 5 hurricane, with wind speeds at the ocean surface up to 185 miles (300 kilometers) per hour, according to the National Oceanic and Atmospheric Administration. The MISR data show that at cloud top, winds near the eye wall (the most destructive part of the storm) were approximately 90 miles per hour (145 kilometers per hour), and the maximum cloud-top wind speed throughout the storm calculated by MISR was 135 miles per hour (220 kilometers per hour). While the hurricane's dominant rotation direction is counter-clockwise, winds near the eye wall are consistently pointing outward from it. This is an indication of outflow, the process by which a hurricane draws in warm, moist air at the surface and ejects cool, dry air at its cloud tops. These data were captured during Terra orbit 94267. An animation is available at https://photojournal.jpl.nasa.gov/catalog/PIA21946

  8. Unique differentiation profile of mouse embryonic stem cells in rotary and stirred tank bioreactors.

    PubMed

    Fridley, Krista M; Fernandez, Irina; Li, Mon-Tzu Alice; Kettlewell, Robert B; Roy, Krishnendu

    2010-11-01

    Embryonic stem (ES)-cell-derived lineage-specific stem cells, for example, hematopoietic stem cells, could provide a potentially unlimited source for transplantable cells, especially for cell-based therapies. However, reproducible methods must be developed to maximize and scale-up ES cell differentiation to produce clinically relevant numbers of therapeutic cells. Bioreactor-based dynamic culture conditions are amenable to large-scale cell production, but few studies have evaluated how various bioreactor types and culture parameters influence ES cell differentiation, especially hematopoiesis. Our results indicate that cell seeding density and bioreactor speed significantly affect embryoid body formation and subsequent generation of hematopoietic stem and progenitor cells in both stirred tank (spinner flask) and rotary microgravity (Synthecon™) type bioreactors. In general, high percentages of hematopoietic stem and progenitor cells were generated in both bioreactors, especially at high cell densities. In addition, Synthecon bioreactors produced more sca-1(+) progenitors and spinner flasks generated more c-Kit(+) progenitors, demonstrating their unique differentiation profiles. cDNA microarray analysis of genes involved in pluripotency, germ layer formation, and hematopoietic differentiation showed that on day 7 of differentiation, embryoid bodies from both bioreactors consisted of all three germ layers of embryonic development. However, unique gene expression profiles were observed in the two bioreactors; for example, expression of specific hematopoietic genes were significantly more upregulated in the Synthecon cultures than in spinner flasks. We conclude that bioreactor type and culture parameters can be used to control ES cell differentiation, enhance unique progenitor cell populations, and provide means for large-scale production of transplantable therapeutic cells.

  9. Effect of metallic walls on dynamos generated by laminar boundary-driven flow in a spherical domain.

    PubMed

    Guervilly, Céline; Wood, Toby S; Brummell, Nicholas H

    2013-11-01

    We present a numerical study of dynamo action in a conducting fluid encased in a metallic spherical shell. Motions in the fluid are driven by differential rotation of the outer metallic shell, which we refer to as "the wall." The two hemispheres of the wall are held in counter-rotation, producing a steady, axisymmetric interior flow consisting of differential rotation and a two-cell meridional circulation with radial inflow in the equatorial plane. From previous studies, this type of flow is known to maintain a stationary equatorial dipole by dynamo action if the magnetic Reynolds number is larger than about 300 and if the outer boundary is electrically insulating. We vary independently the thickness, electrical conductivity, and magnetic permeability of the wall to determine their effect on the dynamo action. The main results are the following: (a) Increasing the conductivity of the wall hinders the dynamo by allowing eddy currents within the wall, which are induced by the relative motion of the equatorial dipole field and the wall. This processes can be viewed as a skin effect or, equivalently, as the tearing apart of the dipole by the differential rotation of the wall, to which the field lines are anchored by high conductivity. (b) Increasing the magnetic permeability of the wall favors dynamo action by constraining the magnetic field lines in the fluid to be normal to the wall, thereby decoupling the fluid from any induction in the wall. (c) Decreasing the wall thickness limits the amplitude of the eddy currents, and is therefore favorable for dynamo action, provided that the wall is thinner than the skin depth. We explicitly demonstrate these effects of the wall properties on the dynamo field by deriving an effective boundary condition in the limit of vanishing wall thickness.

  10. Biodegradation of paint stripper solvents in a modified gas lift loop bioreactor.

    PubMed

    Vanderberg-Twary, L; Steenhoudt, K; Travis, B J; Hanners, J L; Foreman, T M; Brainard, J R

    1997-07-05

    Paint stripping wastes generated during the decontamination and decommissioning of former nuclear facilities contain paint stripping organics (dichloromethane, 2-propanol, and methanol) and bulk materials containing paint pigments. It is desirable to degrade the organic residues as part of an integrated chemical-biological treatment system. We have developed a modified gas lift loop bioreactor employing a defined consortium of Rhodococcus rhodochrous strain OFS and Hyphomicrobium sp. DM-2 that degrades paint stripper organics. Mass transfer coefficients and kinetic constants for biodegradation in the system were determined. It was found that transfer of organic substrates from surrogate waste into the air and further into the liquid medium in the bioreactor were rapid processes, occurring within minutes. Monod kinetics was employed to model the biodegradation of paint stripping organics. Analysis of the bioreactor process was accomplished with BIOLAB, a mathematical code that simulates coupled mass transfer and biodegradation processes. This code was used to fit experimental data to Monod kinetics and to determine kinetic parameters. The BIOLAB code was also employed to compare activities in the bioreactor of individual microbial cultures to the activities of combined cultures in the bioreactor. This code is of benefit for further optimization and scale-up of the bioreactor for treatment of paint stripping and other volatile organic wastes in bulk materials.

  11. The Role of Bioreactors in Ligament and Tendon Tissue Engineering.

    PubMed

    Mace, James; Wheelton, Andy; Khan, Wasim S; Anand, Sanj

    2016-01-01

    Bioreactors are pivotal to the emerging field of tissue engineering. The formation of neotissue from pluripotent cell lineages potentially offers a source of tissue for clinical use without the significant donor site morbidity associated with many contemporary surgical reconstructive procedures. Modern bioreactor design is becoming increasingly complex to provide a both an expandable source of readily available pluripotent cells and to facilitate their controlled differentiation into a clinically applicable ligament or tendon like neotissue. This review presents the need for such a method, challenges in the processes to engineer neotissue and the current designs and results of modern bioreactors in the pursuit of engineered tendon and ligament.

  12. Role of Wall Shear Stress in Cryptosporidium parvum Oocyst Attachment to Environmental Biofilms.

    PubMed

    Luo, Xia; Jedlicka, Sabrina S; Jellison, Kristen L

    2017-12-15

    This study investigated Cryptosporidium parvum oocyst deposition onto biofilms as a function of shear stress under laminar or turbulent flow. Annular rotating bioreactors were used to grow stabilized stream biofilms at shear stresses ranging from 0.038 to 0.46 Pa. These steady-state biofilms were then used to assess the impact of hydrodynamic conditions on C. parvum oocyst attachment. C. parvum deposition onto biofilms followed a pseudo-second-order model under both laminar (after a lag phase) and turbulent flows. The total number of oocysts attached to the biofilm at steady state decreased as the hydrodynamic wall shear stress increased. The oocyst deposition rate constant increased with shear stress but decreased at high shear, suggesting that increasing wall shear stress results in faster attachment of Cryptosporidium due to higher mass transport until the shear forces exceed a critical limit that prevents oocyst attachment. These data show that oocyst attachment in the short and long term are impacted differently by shear: higher shear (to a certain limit) may be associated with faster initial oocyst attachment, but lower shear is associated with greater numbers of oocysts attached at equilibrium. IMPORTANCE This research provides experimental evidence to demonstrate that shear stress plays a critical role in protozoan-pathogen transport and deposition in environmental waters. The data presented in this work expand scientific understanding of Cryptosporidium attachment and fate, which will further influence the development of timely and accurate sampling strategies, as well as advanced water treatment technologies, to target protozoan pathogens in surface waters that serve as municipal drinking water sources. Copyright © 2017 American Society for Microbiology.

  13. A new hybrid treatment system of bioreactors and electrocoagulation for superior removal of organic and nutrient pollutants from municipal wastewater.

    PubMed

    Nguyen, Dinh Duc; Ngo, Huu Hao; Yoon, Yong Soo

    2014-02-01

    This paper evaluated a novel pilot scale hybrid treatment system which combines rotating hanging media bioreactor (RHMBR), submerged membrane bioreactor (SMBR) along with electrocoagulation (EC) as post treatment to treat organic and nutrient pollutants from municipal wastewater. The results indicated that the highest removal efficiency was achieved at the internal recycling ratio as 400% of the influent flow rate which produced a superior effluent quality with 0.26mgBOD5L(-1), 11.46mgCODCrL(-1), 0.00mgNH4(+)-NL(-1), and 3.81mgT-NL(-1), 0.03mgT-PL(-1). During 16months of operation, NH4(+)-N was completely eliminated and T-P removal efficiency was also up to 100%. It was found that increasing in internal recycling ratio could improve the nitrate and nitrogen removal efficiencies. Moreover, the TSS and coliform bacteria concentration after treatment was less than 5mgL(-1) and 30MPNmL(-1), respectively, regardless of internal recycling ratios and its influent concentration. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Vibro-Acoustic Analysis of NASA's Space Shuttle Launch Pad 39A Flame Trench Wall

    NASA Technical Reports Server (NTRS)

    Margasahayam, Ravi N.

    2009-01-01

    A vital element to NASA's manned space flight launch operations is the Kennedy Space Center Launch Complex 39's launch pads A and B. Originally designed and constructed In the 1960s for the Saturn V rockets used for the Apollo missions, these pads were modified above grade to support Space Shuttle missions. But below grade, each of the pad's original walls (including a 42 feet deep, 58 feet wide, and 450 feet long tunnel designed to deflect flames and exhaust gases, the flame trench) remained unchanged. On May 31, 2008 during the launch of STS-124, over 3500 of the. 22000 interlocking refractory bricks that lined east wall of the flame trench, protecting the pad structure were liberated from pad 39A. The STS-124 launch anomaly spawned an agency-wide initiative to determine the failure root cause, to assess the impact of debris on vehicle and ground support equipment safety, and to prescribe corrective action. The investigation encompassed radar imaging, infrared video review, debris transport mechanism analysis using computational fluid dynamics, destructive testing, and non-destructive evaluation, including vibroacoustic analysis, in order to validate the corrective action. The primary focus of this paper is on the analytic approach, including static, modal, and vibro-acoustic analysis, required to certify the corrective action, and ensure Integrity and operational reliability for future launches. Due to the absence of instrumentation (including pressure transducers, acoustic pressure sensors, and accelerometers) in the flame trench, defining an accurate acoustic signature of the launch environment during shuttle main engine/solid rocket booster Ignition and vehicle ascent posed a significant challenge. Details of the analysis, including the derivation of launch environments, the finite element approach taken, and analysistest/ launch data correlation are discussed. Data obtained from the recent launch of STS-126 from Pad 39A was instrumental in validating the

  15. Methods for assessing wall interference in the 2- by 2-foot adaptive-wall wind tunnel

    NASA Technical Reports Server (NTRS)

    Schairer, E. T.

    1986-01-01

    Discussed are two methods for assessing two-dimensional wall interference in the adaptive-wall test section of the NASA Ames 2 x 2-Foot Transonic Wind Tunnel: (1) a method for predicting free-air conditions near the walls of the test section (adaptive-wall methods); and (2) a method for estimating wall-induced velocities near the model (correction methods), both of which methods are based on measurements of either one or two components of flow velocity near the walls of the test section. Each method is demonstrated using simulated wind tunnel data and is compared with other methods of the same type. The two-component adaptive-wall and correction methods were found to be preferable to the corresponding one-component methods because: (1) they are more sensitive to, and give a more complete description of, wall interference; (2) they require measurements at fewer locations; (3) they can be used to establish free-stream conditions; and (4) they are independent of a description of the model and constants of integration.

  16. Periplasmal Physics: The Rotational Dynamics of Spirochetal Flagella

    NASA Astrophysics Data System (ADS)

    Huber, Greg

    2012-02-01

    Spirochetes are distinguished by the location of their flagella, which reside within the periplasm: the tiny space between the bacterial cell wall and the outer membrane. In Borrelia burgdorferi/ (the causative agent of Lyme Disease), rotation of the flagella leads to cellular undulations that drive swimming. Exactly how these shape changes arise due to the forces and torques acting between the flagella and the cell body is unknown. By applying low-Reynolds number hydrodynamic theory to the motion of an elastic flagellum rotating in the periplasm, we show that the flagella are most likely separated from the bacterial cell wall by a lubricating layer of fluid. We obtain analytical solutions for the force and torque on the rotating flagellum through lubrication analysis, as well as through scaling analysis, and find results are in close agreement numerical simulations. (Joint work with J. Yang and C.W. Wolgemuth.)

  17. Three-dimensional rotating flow of MHD single wall carbon nanotubes over a stretching sheet in presence of thermal radiation

    NASA Astrophysics Data System (ADS)

    Nasir, Saleem; Islam, Saeed; Gul, Taza; Shah, Zahir; Khan, Muhammad Altaf; Khan, Waris; Khan, Aurang Zeb; Khan, Saima

    2018-05-01

    In this article the modeling and computations are exposed to introduce the new idea of MHD three-dimensional rotating flow of nanofluid through a stretching sheet. Single wall carbon nanotubes (SWCNTs) are utilized as a nano-sized materials while water is used as a base liquid. Single-wall carbon nanotubes (SWNTs) parade sole assets due to their rare structure. Such structure has significant optical and electronics features, wonderful strength and elasticity, and high thermal and chemical permanence. The heat exchange phenomena are deliberated subject to thermal radiation and moreover the impact of nanoparticles Brownian motion and thermophoresis are involved in the present investigation. For the nanofluid transport mechanism, we implemented the Xue model (Xue, Phys B Condens Matter 368:302-307, 2005). The governing nonlinear formulation based upon the law of conservation of mass, quantity of motion, thermal field and nanoparticles concentrations is first modeled and then solved by homotopy analysis method (HAM). Moreover, the graphical result has been exposed to investigate that in what manner the velocities, heat and nanomaterial concentration distributions effected through influential parameters. The mathematical facts of skin friction, Nusselt number and Sherwood number are presented through numerical data for SWCNTs.

  18. NASA's Webb Telescope ISIM Gets Cubed for Gravity Test

    NASA Image and Video Library

    2017-12-08

    The James Webb Space Telescope's ISIM structure recently endured a "gravity sag test" as it was rotated in what looked like giant cube in a NASA clean room. The Integrated Science Instrument Module (ISIM) that will fly on the Webb telescope was rotated upside down inside a cube-like structure in the cleanroom at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The purpose of "cubing" the ISIM was to test it for "gravity sag," which is to see how much the structure changes under its own weight due to gravity. The Integrated Science Instrument Module (ISIM) is one of three major elements that comprise the Webb Observatory flight system. The others are the Optical Telescope Element (OTE) and the Spacecraft Element (Spacecraft Bus and Sunshield). Read more: 1.usa.gov/1ze7u2l Credit: NASA/Goddard/Chris Gunn NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  19. Nano-ceramic composite scaffolds for bioreactor-based bone engineering.

    PubMed

    Lv, Qing; Deng, Meng; Ulery, Bret D; Nair, Lakshmi S; Laurencin, Cato T

    2013-08-01

    Composites of biodegradable polymers and bioactive ceramics are candidates for tissue-engineered scaffolds that closely match the properties of bone. We previously developed a porous, three-dimensional poly (D,L-lactide-co-glycolide) (PLAGA)/nanohydroxyapatite (n-HA) scaffold as a potential bone tissue engineering matrix suitable for high-aspect ratio vessel (HARV) bioreactor applications. However, the physical and cellular properties of this scaffold are unknown. The present study aims to evaluate the effect of n-HA in modulating PLAGA scaffold properties and human mesenchymal stem cell (HMSC) responses in a HARV bioreactor. By comparing PLAGA/n-HA and PLAGA scaffolds, we asked whether incorporation of n-HA (1) accelerates scaffold degradation and compromises mechanical integrity; (2) promotes HMSC proliferation and differentiation; and (3) enhances HMSC mineralization when cultured in HARV bioreactors. PLAGA/n-HA scaffolds (total number = 48) were loaded into HARV bioreactors for 6 weeks and monitored for mass, molecular weight, mechanical, and morphological changes. HMSCs were seeded on PLAGA/n-HA scaffolds (total number = 38) and cultured in HARV bioreactors for 28 days. Cell migration, proliferation, osteogenic differentiation, and mineralization were characterized at four selected time points. The same amount of PLAGA scaffolds were used as controls. The incorporation of n-HA did not alter the scaffold degradation pattern. PLAGA/n-HA scaffolds maintained their mechanical integrity throughout the 6 weeks in the dynamic culture environment. HMSCs seeded on PLAGA/n-HA scaffolds showed elevated proliferation, expression of osteogenic phenotypic markers, and mineral deposition as compared with cells seeded on PLAGA scaffolds. HMSCs migrated into the scaffold center with nearly uniform cell and extracellular matrix distribution in the scaffold interior. The combination of PLAGA/n-HA scaffolds with HMSCs in HARV bioreactors may allow for the generation of engineered

  20. Optimization of denitrifying bioreactor performance with agricultural residue-based filter media

    USDA-ARS?s Scientific Manuscript database

    Denitrification bioreactors are a promising technology for mitigation of nitrate-nitrogen (NO3-N) losses in subsurface drainage water. Bioreactors are constructed with carbon substrates, typically wood chips, to provide a substrate for denitrifying microorganisms. Columns were packed with wood chips...

  1. CASKAD. Manual Mixing in Bioreactor

    NASA Image and Video Library

    2013-10-05

    ISS037-E-005692 (5 Oct. 2013) --- Russian cosmonaut Sergey Ryazanskiy, Expedition 37 flight engineer, prepares to manually mix samples in a Bioreactor for the CASKAD experiment in the Poisk Mini-Research Module 2 (MRM2) of the International Space Station.

  2. CASKAD. Manual Mixing in Bioreactor

    NASA Image and Video Library

    2013-10-05

    ISS037-E-005694 (5 Oct. 2013) --- Russian cosmonaut Sergey Ryazanskiy, Expedition 37 flight engineer, prepares to manually mix samples in a Bioreactor for the CASKAD experiment in the Poisk Mini-Research Module 2 (MRM2) of the International Space Station.

  3. Turbulent flow in rib-roughened channel under the effect of Coriolis and rotational buoyancy forces

    NASA Astrophysics Data System (ADS)

    Coletti, Filippo; Jacono, David Lo; Cresci, Irene; Arts, Tony

    2014-04-01

    The turbulent flow inside a rotating channel provided with transverse ribs along one wall is studied by means of two-dimensional time-resolved particle image velocimetry. The measurement set-up is mounted on the same rotating disk with the test section, allowing to obtain the same accuracy and resolution as in a non-rotating rig. The Reynolds number is 15 000, and the rotation number is 0.38. As the ribbed wall is heated, both the Coriolis force and the centrifugal force play a role in the fluid dynamics. The mean velocity fields highlight the major impact of the rotational buoyancy (characterized by a buoyancy number of 0.31) on the flow along the leading side of the duct. In particular, since the flow is directed radially outward, the near-wall layers experience significant centripetal buoyancy. The recirculation area behind the obstacles is enlarged to the point of spanning the whole inter-rib space. Also the turbulent fluctuations are significantly altered, and overall augmented, with respect to the non-buoyant case, resulting in higher turbulence levels far from the rib. On the other hand the centrifugal force has little or no impact on the flow along the trailing wall. Vortex identification, proper orthogonal decomposition, and two-point correlations are used to highlight rotational effects, and in particular to determine the dominant scales of the turbulent unsteady flow, the time-dependent behavior of the shear layer and of the recirculation bubble behind the wall-mounted obstacles, the lifetime and advection velocity of the coherent structures.

  4. Fastest Rotating Star Found in Neighboring Galaxy

    NASA Image and Video Library

    2017-12-08

    NASA image release December 5, 2011 This is an artist's concept of the fastest rotating star found to date. The massive, bright young star, called VFTS 102, rotates at a million miles per hour, or 100 times faster than our Sun does. Centrifugal forces from this dizzying spin rate have flattened the star into an oblate shape and spun off a disk of hot plasma, seen edge on in this view from a hypothetical planet. The star may have "spun up" by accreting material from a binary companion star. The rapidly evolving companion later exploded as a supernova. The whirling star lies 160,000 light-years away in the Large Magellanic Cloud, a satellite galaxy of our Milky Way. The team will use NASA's Hubble Space Telescope to make precise measurements of the star's proper motion across space. To read more go to: hubblesite.org/newscenter/archive/releases/2011/39/full/ Image Type: Artwork Credit: NASA, ESA, and G. Bacon (STScI) NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  5. Measurements of NH 3 and CO 2 with Distributed-Feedback Diode Lasers Near 2.0 m in Bioreactor Vent Gases

    NASA Astrophysics Data System (ADS)

    Webber, Michael E.; Claps, Ricardo; Englich, Florian V.; Tittel, Frank K.; Jeffries, Jay B.; Hanson, Ronald K.

    2001-08-01

    Measurements of NH3 and CO2 were made in bioreactor vent gases with distributed-feedback diode-laser sensors operating near 2 m. Calculated spectra of NH3 and CO2 were used to determine the optimum transitions for interrogating with an absorption sensor. For ammonia, a strong and isolated absorption transition at 5016.977 cm-1 was selected for trace gas monitoring. For CO2 , an isolated transition at 5007.787 cm-1 was selected to measure widely varying concentrations [500 parts per million (ppm) to 10% ,] with sufficient signal for low mole fractions and without being optically thick for high mole fractions. Using direct absorption and a 36-m total path-length multipass flow-through cell, we achieved a minimum detectivity of 0.25 ppm for NH3 and 40 ppm for CO2 . We report on the quasi-continuous field measurements of NH3 and CO2 concentration in bioreactor vent gases that were recorded at NASA Johnson Space Center with a portable and automated sensor system over a 45-h data collection window.

  6. The Chronicles Wall

    NASA Image and Video Library

    2017-05-03

    Brass plaques engraved with the names of Gatha Cottee of NASA Public Affairs, Walter Cronkite of CBS News and Bill Cummins of WEZY Radio are among the list of "The Chroniclers," a roll of honor on the wall at the NASA News Center at Kennedy Space Center in Florida. In this facility reporters from television, radio, print and online media outlets have monitored countless launches, landings and other space events in order to deliver the news to the world. The Chroniclers program recognizes retirees of the news and communications business who helped spread news of American space exploration from Kennedy Space Center for ten years or more.

  7. Bioreactor droplets from liposome-stabilized all-aqueous emulsions

    NASA Astrophysics Data System (ADS)

    Dewey, Daniel C.; Strulson, Christopher A.; Cacace, David N.; Bevilacqua, Philip C.; Keating, Christine D.

    2014-08-01

    Artificial bioreactors are desirable for in vitro biochemical studies and as protocells. A key challenge is maintaining a favourable internal environment while allowing substrate entry and product departure. We show that semipermeable, size-controlled bioreactors with aqueous, macromolecularly crowded interiors can be assembled by liposome stabilization of an all-aqueous emulsion. Dextran-rich aqueous droplets are dispersed in a continuous polyethylene glycol (PEG)-rich aqueous phase, with coalescence inhibited by adsorbed ~130-nm diameter liposomes. Fluorescence recovery after photobleaching and dynamic light scattering data indicate that the liposomes, which are PEGylated and negatively charged, remain intact at the interface for extended time. Inter-droplet repulsion provides electrostatic stabilization of the emulsion, with droplet coalescence prevented even for submonolayer interfacial coatings. RNA and DNA can enter and exit aqueous droplets by diffusion, with final concentrations dictated by partitioning. The capacity to serve as microscale bioreactors is established by demonstrating a ribozyme cleavage reaction within the liposome-coated droplets.

  8. Bioreactor droplets from liposome-stabilized all-aqueous emulsions.

    PubMed

    Dewey, Daniel C; Strulson, Christopher A; Cacace, David N; Bevilacqua, Philip C; Keating, Christine D

    2014-08-20

    Artificial bioreactors are desirable for in vitro biochemical studies and as protocells. A key challenge is maintaining a favourable internal environment while allowing substrate entry and product departure. We show that semipermeable, size-controlled bioreactors with aqueous, macromolecularly crowded interiors can be assembled by liposome stabilization of an all-aqueous emulsion. Dextran-rich aqueous droplets are dispersed in a continuous polyethylene glycol (PEG)-rich aqueous phase, with coalescence inhibited by adsorbed ~130-nm diameter liposomes. Fluorescence recovery after photobleaching and dynamic light scattering data indicate that the liposomes, which are PEGylated and negatively charged, remain intact at the interface for extended time. Inter-droplet repulsion provides electrostatic stabilization of the emulsion, with droplet coalescence prevented even for submonolayer interfacial coatings. RNA and DNA can enter and exit aqueous droplets by diffusion, with final concentrations dictated by partitioning. The capacity to serve as microscale bioreactors is established by demonstrating a ribozyme cleavage reaction within the liposome-coated droplets.

  9. Miniature Bioreactor System for Long-Term Cell Culture

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R.; Kleis, Stanley J.; Geffert, Sandara K.

    2010-01-01

    A prototype miniature bioreactor system is designed to serve as a laboratory benchtop cell-culturing system that minimizes the need for relatively expensive equipment and reagents and can be operated under computer control, thereby reducing the time and effort required of human investigators and reducing uncertainty in results. The system includes a bioreactor, a fluid-handling subsystem, a chamber wherein the bioreactor is maintained in a controlled atmosphere at a controlled temperature, and associated control subsystems. The system can be used to culture both anchorage-dependent and suspension cells, which can be either prokaryotic or eukaryotic. Cells can be cultured for extended periods of time in this system, and samples of cells can be extracted and analyzed at specified intervals. By integrating this system with one or more microanalytical instrument(s), one can construct a complete automated analytical system that can be tailored to perform one or more of a large variety of assays.

  10. Bioreactors for guiding muscle tissue growth and development.

    PubMed

    Dennis, R G; Smith, B; Philp, A; Donnelly, K; Baar, K

    2009-01-01

    Muscle tissue bioreactors are devices which are employed to guide and monitor the development of engineered muscle tissue. These devices have a modern history that can be traced back more than a century, because the key elements of muscle tissue bioreactors have been studied for a very long time. These include barrier isolation and culture of cells, tissues and organs after isolation from a host organism; the provision of various stimuli intended to promote growth and maintain the muscle, such as electrical and mechanical stimulation; and the provision of a perfusate such as culture media or blood derived substances. An accurate appraisal of our current progress in the development of muscle bioreactors can only be made in the context of the history of this endeavor. Modern efforts tend to focus more upon the use of computer control and the application of mechanical strain as a stimulus, as well as substrate surface modifications to induce cellular organization at the early stages of culture of isolated muscle cells.

  11. PERFORMANCE OF NORTH AMERICAN BIOREACTOR LANDFILLS: II. CHEMICAL AND BIOLOGICAL CHARACTERISTICS

    EPA Science Inventory

    The objective of this research was to examine the performance of five North American bioreactor landfills. This paper represents the second of a two part series and addresses biological and chemical aspects of bioreactor performance including gas production and management, and l...

  12. Visualizing medium and biodistribution in complex cell culture bioreactors using in vivo imaging.

    PubMed

    Ratcliffe, E; Thomas, R J; Stacey, A J

    2014-01-01

    There is a dearth of technology and methods to aid process characterization, control and scale-up of complex culture platforms that provide niche micro-environments for some stem cell-based products. We have demonstrated a novel use of 3d in vivo imaging systems to visualize medium flow and cell distribution within a complex culture platform (hollow fiber bioreactor) to aid characterization of potential spatial heterogeneity and identify potential routes of bioreactor failure or sources of variability. This can then aid process characterization and control of such systems with a view to scale-up. Two potential sources of variation were observed with multiple bioreactors repeatedly imaged using two different imaging systems: shortcutting of medium between adjacent inlet and outlet ports with the potential to create medium gradients within the bioreactor, and localization of bioluminescent murine 4T1-luc2 cells upon inoculation with the potential to create variable seeding densities at different points within the cell growth chamber. The ability of the imaging technique to identify these key operational bioreactor characteristics demonstrates an emerging technique in troubleshooting and engineering optimization of bioreactor performance. © 2013 American Institute of Chemical Engineers.

  13. Regulation of mesenchymal stem cell 3D microenvironment: From macro to microfluidic bioreactors.

    PubMed

    Sart, Sébastien; Agathos, Spiros N; Li, Yan; Ma, Teng

    2016-01-01

    Human mesenchymal stem cells (hMSCs) have emerged as an important cell type in cell therapy and tissue engineering. In these applications, maintaining the therapeutic properties of hMSCs requires tight control of the culture environments and the structural cell organizations. Bioreactor systems are essential tools to achieve these goals in the clinical-scale expansion and tissue engineering applications. This review summarizes how different bioreactors provide cues to regulate the structure and the chemico-mechanical microenvironment of hMSCs with a focus on 3D organization. In addition to conventional bioreactors, recent advances in microfluidic bioreactors as a novel approach to better control the hMSC microenvironment are also discussed. These advancements highlight the key role of bioreactor systems in preserving hMSC's functional properties by providing dynamic and temporal regulation of in vitro cellular microenvironment. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Bioreactors as engineering support to treat cardiac muscle and vascular disease.

    PubMed

    Massai, Diana; Cerino, Giulia; Gallo, Diego; Pennella, Francesco; Deriu, Marco A; Rodriguez, Andres; Montevecchi, Franco M; Bignardi, Cristina; Audenino, Alberto; Morbiducci, Umberto

    2013-01-01

    Cardiovascular disease is the leading cause of morbidity and mortality in the Western World. The inability of fully differentiated, load-bearing cardiovascular tissues to in vivo regenerate and the limitations of the current treatment therapies greatly motivate the efforts of cardiovascular tissue engineering to become an effective clinical strategy for injured heart and vessels. For the effective production of organized and functional cardiovascular engineered constructs in vitro, a suitable dynamic environment is essential, and can be achieved and maintained within bioreactors. Bioreactors are technological devices that, while monitoring and controlling the culture environment and stimulating the construct, attempt to mimic the physiological milieu. In this study, a review of the current state of the art of bioreactor solutions for cardiovascular tissue engineering is presented, with emphasis on bioreactors and biophysical stimuli adopted for investigating the mechanisms influencing cardiovascular tissue development, and for eventually generating suitable cardiovascular tissue replacements.

  15. Compressional Alfvén eigenmodes in rotating spherical tokamak plasmas

    DOE PAGES

    Smith, H. M.; Fredrickson, E. D.

    2017-02-07

    Spherical tokamaks often have a considerable toroidal plasma rotation of several tens of kHz. Compressional Alfvén eigenmodes in such devices therefore experience a frequency shift, which if the plasma were rotating as a rigid body, would be a simple Doppler shift. However, since the rotation frequency depends on minor radius, the eigenmodes are affected in a more complicated way. The eigenmode solver CAE3B (Smith et al 2009 Plasma Phys. Control. Fusion 51 075001) has been extended to account for toroidal plasma rotation. The results show that the eigenfrequency shift due to rotation can be approximated by a rigid body rotationmore » with a frequency computed from a spatial average of the real rotation profile weighted with the eigenmode amplitude. To investigate the effect of extending the computational domain to the vessel wall, a simplified eigenmode equation, yet retaining plasma rotation, is solved by a modified version of the CAE code used in Fredrickson et al (2013 Phys. Plasmas 20 042112). Lastly, both solving the full eigenmode equation, as in the CAE3B code, and placing the boundary at the vessel wall, as in the CAE code, significantly influences the calculated eigenfrequencies.« less

  16. Clinical scale rapid expansion of lymphocytes for adoptive cell transfer therapy in the WAVE® bioreactor

    PubMed Central

    2012-01-01

    Background To simplify clinical scale lymphocyte expansions, we investigated the use of the WAVE®, a closed system bioreactor that utilizes active perfusion to generate high cell numbers in minimal volumes. Methods We have developed an optimized rapid expansion protocol for the WAVE bioreactor that produces clinically relevant numbers of cells for our adoptive cell transfer clinical protocols. Results TIL and genetically modified PBL were rapidly expanded to clinically relevant scales in both static bags and the WAVE bioreactor. Both bioreactors produced comparable numbers of cells; however the cultures generated in the WAVE bioreactor had a higher percentage of CD4+ cells and had a less activated phenotype. Conclusions The WAVE bioreactor simplifies the process of rapidly expanding tumor reactive lymphocytes under GMP conditions, and provides an alternate approach to cell generation for ACT protocols. PMID:22475724

  17. MONITORING GUIDANCE FOR BIOREACTOR LANDFILLS

    EPA Science Inventory

    Experimental bioreactor landfill operations at operating Municipal Solid Waste (MSW) landfills can be approved under the research development and demonstration (RD&D) provisions of 30CFR 258.4. To provide a basis for consistent data collection for future decision-making in suppor...

  18. MONITORING APPROACHES FOR BIOREACTOR LANDFILLS

    EPA Science Inventory

    Experimental bioreactor landfill operations at operating Municipal Solid Waste (MSW) landfills can be approved under the research development and demonstration (RD&D) provisions of 40 CFR 258.4. To provide a basis for consistent data collection for future decision-making in suppo...

  19. Wall roughness induces asymptotic ultimate turbulence

    NASA Astrophysics Data System (ADS)

    Zhu, Xiaojue; Verschoof, Ruben A.; Bakhuis, Dennis; Huisman, Sander G.; Verzicco, Roberto; Sun, Chao; Lohse, Detlef

    2018-04-01

    Turbulence governs the transport of heat, mass and momentum on multiple scales. In real-world applications, wall-bounded turbulence typically involves surfaces that are rough; however, characterizing and understanding the effects of wall roughness on turbulence remains a challenge. Here, by combining extensive experiments and numerical simulations, we examine the paradigmatic Taylor-Couette system, which describes the closed flow between two independently rotating coaxial cylinders. We show how wall roughness greatly enhances the overall transport properties and the corresponding scaling exponents associated with wall-bounded turbulence. We reveal that if only one of the walls is rough, the bulk velocity is slaved to the rough side, due to the much stronger coupling to that wall by the detaching flow structures. If both walls are rough, the viscosity dependence is eliminated, giving rise to asymptotic ultimate turbulence—the upper limit of transport—the existence of which was predicted more than 50 years ago. In this limit, the scaling laws can be extrapolated to arbitrarily large Reynolds numbers.

  20. Review of nonconventional bioreactor technology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Turick, C.E.; Mcllwain, M.E.

    1993-09-01

    Biotechnology will significantly affect many industrial sectors in the future. Industrial sectors that will be affected include pharmaceutical, chemical, fuel, agricultural, and environmental remediation. Future research is needed to improve bioprocessing efficiency and cost-effectiveness in order to compete with traditional technologies. This report describes recent advances in bioprocess technologies and bioreactor designs and relates them to problems encountered in many industrial bioprocessing operations. The primary focus is directed towards increasing gas and vapor transfer for enhanced bioprocess kinetics as well as unproved by-product separation and removal. The advantages and disadvantages of various conceptual designs such as hollow-fiber, gas-phase, hyperbaric/hypobaric, andmore » electrochemical bioreactors are also discussed. Specific applications that are intended for improved bioprocesses include coal desulfurization, coal liquefaction, soil bioremediation, biomass conversion to marketable chemicals, biomining, and biohydrometallurgy as well as bioprocessing of gases and vapors.« less

  1. Polygons on a rotating fluid surface.

    PubMed

    Jansson, Thomas R N; Haspang, Martin P; Jensen, Kåre H; Hersen, Pascal; Bohr, Tomas

    2006-05-05

    We report a novel and spectacular instability of a fluid surface in a rotating system. In a flow driven by rotating the bottom plate of a partially filled, stationary cylindrical container, the shape of the free surface can spontaneously break the axial symmetry and assume the form of a polygon rotating rigidly with a speed different from that of the plate. With water, we have observed polygons with up to 6 corners. It has been known for many years that such flows are prone to symmetry breaking, but apparently the polygonal surface shapes have never been observed. The creation of rotating internal waves in a similar setup was observed for much lower rotation rates, where the free surface remains essentially flat [J. M. Lopez, J. Fluid Mech. 502, 99 (2004). We speculate that the instability is caused by the strong azimuthal shear due to the stationary walls and that it is triggered by minute wobbling of the rotating plate.

  2. Implementation of the WICS Wall Interference Correction System at the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Iyer, Venkit; Everhart, Joel L.; Bir, Pamela J.; Ulbrich, Norbert

    2000-01-01

    The Wall Interference Correction System (WICS) is operational at the National Transonic Facility (NTF) of NASA Langley Research Center (NASA LaRC) for semispan and full span tests in the solid wall (slots covered) configuration. The method is based on the wall pressure signature method for computing corrections to the measured parameters. It is an adaptation of the WICS code operational at the 12 ft pressure wind tunnel (12ft PWT) of NASA Ames Research Center (NASA ARC). This paper discusses the details of implementation of WICS at the NTF including tunnel calibration, code modifications for tunnel and support geometry, changes made for the NTF wall orifices layout, details of interfacing with the tunnel data processing system, and post-processing of results. Example results of applying WICS to a semispan test and a full span test are presented. Comparison with classical correction results and an analysis of uncertainty in the corrections are also given. As a special application of the code, the Mach number calibration data from a centerline pipe test was computed by WICS. Finally, future work for expanding the applicability of the code including online implementation is discussed.

  3. Implementation of the WICS Wall Interference Correction System at the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Iyer, Venkit; Martin, Lockheed; Everhart, Joel L.; Bir, Pamela J.; Ulbrich, Norbert

    2000-01-01

    The Wall Interference Correction System (WICS) is operational at the National Transonic Facility (NTF) of NASA Langley Research Center (NASA LaRC) for semispan and full span tests in the solid wall (slots covered) configuration, The method is based on the wall pressure signature method for computing corrections to the measured parameters. It is an adaptation of the WICS code operational at the 12 ft pressure wind tunnel (12ft PWT) of NASA Ames Research Center (NASA ARC). This paper discusses the details of implementation of WICS at the NTF including, tunnel calibration, code modifications for tunnel and support geometry, changes made for the NTF wall orifices layout, details of interfacing with the tunnel data processing system, and post-processing of results. Example results of applying WICS to a semispan test and a full span test are presented. Comparison with classical correction results and an analysis of uncertainty in the corrections are also given. As a special application of the code, the Mach number calibration data from a centerline pipe test was computed by WICS. Finally, future work for expanding the applicability of the code including online implementation is discussed.

  4. Electrical stimulation for enhanced denitrification in woodchip bioreactors: Opportunities and challenges

    USDA-ARS?s Scientific Manuscript database

    Woodchip bioreactors are being implemented for the removal of nitrates in groundwater and tile water drainage. However, low nitrate removals in denitrifying woodchip bioreactors have been observed for short hydraulic retention time (HRT) and low water temperature (< 10ºC). One potential approach to ...

  5. Bioreactor design for successive culture of anchorage-dependent cells operated in an automated manner.

    PubMed

    Kino-Oka, Masahiro; Ogawa, Natsuki; Umegaki, Ryota; Taya, Masahito

    2005-01-01

    A novel bioreactor system was designed to perform a series of batchwise cultures of anchorage-dependent cells by means of automated operations of medium change and passage for cell transfer. The experimental data on contamination frequency ensured the biological cleanliness in the bioreactor system, which facilitated the operations in a closed environment, as compared with that in flask culture system with manual handlings. In addition, the tools for growth prediction (based on growth kinetics) and real-time growth monitoring by measurement of medium components (based on small-volume analyzing machinery) were installed into the bioreactor system to schedule the operations of medium change and passage and to confirm that culture proceeds as scheduled, respectively. The successive culture of anchorage-dependent cells was conducted with the bioreactor running in an automated way. The automated bioreactor gave a successful culture performance with fair accordance to preset scheduling based on the information in the latest subculture, realizing 79- fold cell expansion for 169 h. In addition, the correlation factor between experimental data and scheduled values through the bioreactor performance was 0.998. It was concluded that the proposed bioreactor with the integration of the prediction and monitoring tools could offer a feasible system for the manufacturing process of cultured tissue products.

  6. Enhanced Denitrification in Roadside Ditches with Bioreactors

    NASA Astrophysics Data System (ADS)

    Pluer, W.; Schneider, R.; Walter, M. T.

    2016-12-01

    Nitrate (NO3) pollution remains a water quality problem in agriculture-dominated watersheds despite decades of research and concerted efforts. Excess NO3 causes eutrophication in estuarine and marine ecosystems far downstream of the pollution source. Denitrification reduces NO3 to inert dinitrogen gas; this process occurs naturally in saturated areas of the landscape but this rate cannot keep up with the runoff rate due to fertilizer and manure applications. Researchers developed denitrifying bioreactors as a solution to encourage denitrification at the field level. Denitrifying bioreactors remove NO3 at a significantly higher rate (>2 g N m-2 d-1) than natural systems such as wetlands (<0.5 g N m-2 d-1). Most current designs of denitrifying bioreactors necessitate connection with tile drainage as the inflow source of water and NO3. It also requires a portion of farmland (typically <1% of field area is needed) which farmers can be reluctant to relinquish. Meanwhile, road ditches commonly run along agricultural fields, channeling runoff and NO3 to surface water. Because the ditches are designed to avoid flooding, they channel water rapidly and minimize time and contact with soil microbes for denitrification (denitrification rates in ditches are typically <0.1 g N m-2 d-1). Modified denitrifying bioreactors placed in road ditches could provide high NO3 removal in already marginal land, especially at baseflow conditions. A pilot study of this shows instantaneous NO3 removal rates up to 110 g N m-2 d-1 in the first year. Continued results similar to this pilot study and wider application could significantly increase ditch denitrification and help mitigate NO3 pollution.

  7. Feedback Control of Resistive Wall Modes in Slowly Rotating DIII-D Plasmas

    NASA Astrophysics Data System (ADS)

    Okabayashi, M.; Chance, M. S.; Takahashi, H.; Garofalo, A. M.; Reimerdes, H.; in, Y.; Chu, M. S.; Jackson, G. L.; La Haye, R. J.; Strait, E. J.

    2006-10-01

    In slowly rotating plasmas on DIII-D, the requirement of RWM control feedback have been identified, using a MHD code along with measured power supply characteristics. It was found that a small time delay is essential for achieving high beta if no rotation stabilization exists. The overall system delay or the band pass time constant should be in the range of 0.4 of the RWM growth time. Recently the control system was upgraded using twelve linear audio amplifiers and a faster digital control system, reducing the time-delay from 600 to 100 μs. The advantage has been clearly observed when the RWMs excited by ELMs were effectively controlled by feedback even if the rotation transiently slowed nearly to zero. This study provides insight on stability in the low- rotation plasmasw with balanced NBI in DIII-D and also in ITER.

  8. Generating cycle flow between dark and light zones with double paddlewheels to improve microalgal growth in a flat plate photo-bioreactor.

    PubMed

    Cheng, Jun; Xu, Junchen; Lu, Hongxiang; Ye, Qing; Liu, Jianzhong; Zhou, Junhu

    2018-08-01

    Double paddlewheels were proposed to generate cycle flow for increasing horizontal fluid velocity between dark and light zones in a flat plate photo-bioreactor, which strengthened the mass transfer and the mixing effect to improve microalgal growth with 15% CO 2 . Numerical fluid dynamics were used to simulate the cycle flow field with double paddlewheels. The local flow field measured with particle image velocimetry fitted well with the numerical simulation results. The horizontal fluid velocity in the photo-bioreactor was markedly increased from 5.8 × 10 -5  m/s to 0.45 m/s with the rotation of double paddlewheels, resulting in a decreased dark/light cycle period. Therefore, bubble formation time and diameter reduced by 24.4% and 27.4%, respectively. Meanwhile, solution mixing time reduced by 31.3% and mass transfer coefficient increased by 41.2%. The biomass yield of microalgae Nannochloropsis Oceanic increased by 127.1% with double paddlewheels under 15% CO 2 condition. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Quantitative analysis of microbial biomass yield in aerobic bioreactor.

    PubMed

    Watanabe, Osamu; Isoda, Satoru

    2013-12-01

    We have studied the integrated model of reaction rate equations with thermal energy balance in aerobic bioreactor for food waste decomposition and showed that the integrated model has the capability both of monitoring microbial activity in real time and of analyzing biodegradation kinetics and thermal-hydrodynamic properties. On the other hand, concerning microbial metabolism, it was known that balancing catabolic reactions with anabolic reactions in terms of energy and electron flow provides stoichiometric metabolic reactions and enables the estimation of microbial biomass yield (stoichiometric reaction model). We have studied a method for estimating real-time microbial biomass yield in the bioreactor during food waste decomposition by combining the integrated model with the stoichiometric reaction model. As a result, it was found that the time course of microbial biomass yield in the bioreactor during decomposition can be evaluated using the operational data of the bioreactor (weight of input food waste and bed temperature) by the combined model. The combined model can be applied to manage a food waste decomposition not only for controlling system operation to keep microbial activity stable, but also for producing value-added products such as compost on optimum condition. Copyright © 2013 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  10. Analysis of buoyancy effect on fully developed laminar heat transfer in a rotating tube

    NASA Technical Reports Server (NTRS)

    Siegel, R.

    1985-01-01

    Laminar heat transfer is analyzed in a tube rotating about an axis perpendicular to the tube axis. The solution applies for flow that is either radially outward from the axis of rotation, or radially inward toward the axis of rotation. The conditions are fully developed, and there is uniform heat addition at the tube wall. The analysis is performed by expanding velocities and temperature in power series using the Taylor number as a perturbation parameter. Coriolis and buoyancy forces caused by tube rotation are included, and the solution is calculated through second-order terms. The secondary flow induced by the Coriolis terms always tends to increase the heat transfer coefficient; this effect can dominate for small wall heating. For radial inflow, buoyancy also tends to improve heat transfer. For radial outflow, however, buoyancy tends to reduce heat transfer; for large wall heating this effect can dominate, and there is a net reduction in heat transfer coefficient.

  11. Use of ATP to characterize biomass viability in freely suspended and immobilized cell bioreactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gikas, P.; Livingston, A.G.

    1993-12-01

    This work describes investigations into the viability of cells growing on 3,4-dichloroaniline (34DCA). Two bio-reactors are employed for microbial growth, a continuous stirred tank (CST) bioreactor with a 2-L working volume, and a three-phase air lift (TPAL) bioreactor with a 3-L working volume. Experiments have been performed at several dilution rates between 0.027 and 0.115 h[sup [minus]1] in the CST bioreactor and between 0.111 and 0.500h[sup [minus]1] in the TPAL bioreactor. The specific ATP concentration was calculated at each dilution rate in the suspended biomass in both bioreactors as well as in the immobilized biomass in the TPAL bioreactor. Themore » cultures were inspected under an electron microscope to monitor compositional changes. Results from the CST bioreactor showed that the biomass-specific ATP concentration increases from 0.44 to 1.86 mg ATP g[sup [minus]1] dry weight (dw) as dilution rate increases from 0.027 to 0.115 h[sup [minus]1]. At this upper dilution rate the cells were washed out. The specific ATP concentration reached a limiting average value of 1.73 mg ATP g[sup [minus]1] dw, which is assumed to be the quantity of ATP in 100% viable biomass, In the TPAL bioreactor, the ATP level increased with dilution rat in both the immobilized and suspended biomass. The specific ATP concentration in the immobilized biomass increased from approximately 0.051 mg ATP g[sup [minus]1] dw at dilution rates between 0.111 and 0.200 h[sup [minus]1] to approximately 0.119 mg ATP g[sup [minus]1] dw at dilution rates between 0.300 and 0.500 h[sup [minus]1].« less

  12. Replaceable Sensor System for Bioreactor Monitoring

    NASA Technical Reports Server (NTRS)

    Mayo, Mike; Savoy, Steve; Bruno, John

    2006-01-01

    A sensor system was proposed that would monitor spaceflight bioreactor parameters. Not only will this technology be invaluable in the space program for which it was developed, it will find applications in medical science and industrial laboratories as well. Using frequency-domain-based fluorescence lifetime technology, the sensor system will be able to detect changes in fluorescence lifetime quenching that results from displacement of fluorophorelabeled receptors bound to target ligands. This device will be used to monitor and regulate bioreactor parameters including glucose, pH, oxygen pressure (pO2), and carbon dioxide pressure (pCO2). Moreover, these biosensor fluorophore receptor-quenching complexes can be designed to further detect and monitor for potential biohazards, bioproducts, or bioimpurities. Biosensors used to detect biological fluid constituents have already been developed that employ a number of strategies, including invasive microelectrodes (e.g., dark electrodes), optical techniques including fluorescence, and membrane permeable systems based on osmotic pressure. Yet the longevity of any of these sensors does not meet the demands of extended use in spacecraft habitat or bioreactor monitoring. It was therefore necessary to develop a sensor platform that could determine not only fluid variables such as glucose concentration, pO2, pCO2, and pH but can also regulate these fluid variables with controlled feedback loop.

  13. Rotational Motion of Axisymmetric Marangoni Swimmers

    NASA Astrophysics Data System (ADS)

    Rothstein, Jonathan; Uvanovic, Nick

    2017-11-01

    A series of experiments will be presented investigating the motion of millimeter-sized particles on the surface of water. The particles were partially coated with ethanol and carefully placed on a water interface in a series of Petri dishes with different diameters. High speed particle motion was driven by strong surface tension gradients as the ethanol slowly diffuses from the particles into the water resulting in a Marangoni flow. The velocity and acceleration of the particles where measured. In addition to straight line motion, the presence of the bounding walls of the circular Petri dish was found to induce an asymmetric, rotational motion of the axisymmetric Marangoni swimmers. The rotation rate and radius of curvature was found to be a function of the size of the Petri dish and the curvature of the air-water interface near the edge of the dish. For large Petri dishes or small particles, rotation motion was observed far from the bounding walls. In these cases, the symmetry break appears to be the result of the onset of votex shedding. Finally, multiple spherical particles were observed to undergo assembly driven by capillary forces followed by explosive disassembly.

  14. Use of bioreactors for culturing human retinal organoids improves photoreceptor yields.

    PubMed

    Ovando-Roche, Patrick; West, Emma L; Branch, Matthew J; Sampson, Robert D; Fernando, Milan; Munro, Peter; Georgiadis, Anastasios; Rizzi, Matteo; Kloc, Magdalena; Naeem, Arifa; Ribeiro, Joana; Smith, Alexander J; Gonzalez-Cordero, Anai; Ali, Robin R

    2018-06-13

    The use of human pluripotent stem cell-derived retinal cells for cell therapy strategies and disease modelling relies on the ability to obtain healthy and organised retinal tissue in sufficient quantities. Generating such tissue is a lengthy process, often taking over 6 months of cell culture, and current approaches do not always generate large quantities of the major retinal cell types required. We adapted our previously described differentiation protocol to investigate the use of stirred-tank bioreactors. We used immunohistochemistry, flow cytometry and electron microscopy to characterise retinal organoids grown in standard and bioreactor culture conditions. Our analysis revealed that the use of bioreactors results in improved laminar stratification as well as an increase in the yield of photoreceptor cells bearing cilia and nascent outer-segment-like structures. Bioreactors represent a promising platform for scaling up the manufacture of retinal cells for use in disease modelling, drug screening and cell transplantation studies.

  15. Electro-osmotic flow in a rotating rectangular microchannel

    PubMed Central

    Ng, Chiu-On; Qi, Cheng

    2015-01-01

    An analytical model is presented for low-Rossby-number electro-osmotic flow in a rectangular channel rotating about an axis perpendicular to its own. The flow is driven under the combined action of Coriolis, pressure, viscous and electric forces. Analytical solutions in the form of eigenfunction expansions are developed for the problem, which is controlled by the rotation parameter (or the inverse Ekman number), the Debye parameter, the aspect ratio of the channel and the distribution of zeta potentials on the channel walls. Under the conditions of fast rotation and a thin electric double layer (EDL), an Ekman–EDL develops on the horizontal walls. This is essentially an Ekman layer subjected to electrokinetic effects. The flow structure of this boundary layer as a function of the Ekman layer thickness normalized by the Debye length is investigated in detail in this study. It is also shown that the channel rotation may have qualitatively different effects on the flow rate, depending on the channel width and the zeta potential distributions. Axial and secondary flows are examined in detail to reveal how the development of a geostrophic core may lead to a rise or fall of the mean flow. PMID:26345088

  16. Crater Wall in Van de Graaff

    NASA Image and Video Library

    2010-02-11

    This image taken NASA Lunar Reconnaissance Orbiter shows the wall of crater Van de Graaff C, where brighter material is exposed by more active processes associated with steeper slopes, recent small craters, and even individual rolling boulders.

  17. Secondary metabolism in simulated microgravity: beta-lactam production by Streptomyces clavuligerus

    NASA Technical Reports Server (NTRS)

    Fang, A.; Pierson, D. L.; Mishra, S. K.; Koenig, D. W.; Demain, A. L.

    1997-01-01

    Rotating bioreactors designed at NASA's Johnson Space Center were used to simulate a microgravity environment in which to study secondary metabolism. The system examined was beta-lactam antibiotic production by Streptomyces clavuligerus. Both growth and beta-lactam production occurred in simulated microgravity. Stimulatory effects of phosphate and L-lysine, previously detected in normal gravity, also occurred in simulated microgravity. The degree of beta-lactam antibiotic production was markedly inhibited by simulated microgravity.

  18. Reduced Differentiation Efficiency of Murine Embryonic Stem Cells in Stirred Suspension Bioreactors

    PubMed Central

    Taiani, Jaymi T.; Krawetz, Roman J.; zur Nieden, Nicole I.; Wu, Yiru Elizabeth; Kallos, Michael S.; Matyas, John R.

    2010-01-01

    The use of embryonic stem cells (ESCs) for regenerative medicine has generated increased attention due to the favorable attributes of these cells; namely, they are pluripotent and possess long-term self-renewal capacity. The initial aims of the present study were: (i) to use stirred suspension bioreactors to expand and differentiate ESCs into osteogenic and chondrogenic cell types and (ii) to explore if these ESC-derived cells influenced skeletal healing in an in vivo fracture model. We show that differentiation protocols used in static culture are insufficient when applied directly to suspension culture bioreactors. Moreover, when bioreactor-differentiated cells are transplanted into a burr-hole defect in bone, severe disruption of the bone architecture was noted at the fracture site, as determined by microcomputed tomography (microCT) imaging and histopathology. Further characterization of the bioreactor-differentiated cultures revealed that a subpopulation of cells in the resulting aggregates expressed the pluripotency marker Oct-4 in the nucleus. Nuclear Oct-4 expression persisted even after 30 days of culture in the absence of leukemia inhibitory factor (LIF). Remarkably, and unlike ESCs differentiated into skeletal cell types in static cultures, bioreactor-differentiated aggregates implanted subcutaneously into SCID mice formed teratomas. The development of effective ESC differentiation protocols for suspension bioreactors will require a more complete understanding of the environmental conditions within these culture systems and the influence that these conditions have on the regulation of pluripotency and differentiation in ESCs. PMID:19775198

  19. Bioreactor Landfill Research and Demonstration Project Northern Oaks Landfill, Harrison, MI

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Xiando; Voice, Thomas; and Hashsham, Syed A.

    2006-08-29

    A bioreactor landfill cell with 1.2-acre footprint was constructed, filled, operated, and monitored at Northern Oaks Recycling and Disposal Facility (NORDF) at Harrison, MI. With a filled volume of 74,239 cubic yards, the cell contained approximately 35,317 tons of municipal solid waste (MSW) and 20,777 tons of cover soil. It was laid on the slope of an existing cell but separated by a geosynthetic membrane liner. After the cell reached a design height of 60 feet, it was covered with a geosynthetic membrane cap. A three-dimensional monitoring system to collect data at 48 different locations was designed and installed duringmore » the construction phase of the bioreactor cell. Each location had a cluster of monitoring devices consisting of a probe to monitor moisture and temperature, a leachate collection basin, and a gas sampling port. An increase in moisture content of the MSW in the bioreactor cell was achieved by pumping leachate collected on-site from various other cells, as well as recirculation of leachate from the bioreactor landfill cell itself. Three types of leachate injection systems were evaluated in this bioreactor cell for their efficacy to distribute pumped leachate uniformly: a leachate injection pipe buried in a 6-ft wide horizontal stone mound, a 15-ft wide geocomposite drainage layer, and a 60-ft wide geocomposite drainage layer. All leachate injection systems were installed on top of the compacted waste surface. The distribution of water and resulting MSW moisture content throughout the bioreactor cell was found to be similar for the three designs. Water coming into and leaving the cell (leachate pumped in, precipitation, snow, evaporation, and collected leachate) was monitored in order to carry out a water balance. Using a leachate injection rate of 26 – 30 gal/yard3, the average moisture content increased from 25% to 35% (wet based) over the period of this study. One of the key aspects of this bioreactor landfill study was to evaluate

  20. Thinking beyond the Bioreactor Box: Incorporating Stream Ecology into Edge-of-Field Nitrate Management.

    PubMed

    Goeller, Brandon C; Febria, Catherine M; Harding, Jon S; McIntosh, Angus R

    2016-05-01

    Around the world, artificially drained agricultural lands are significant sources of reactive nitrogen to stream ecosystems, creating substantial stream health problems. One management strategy is the deployment of denitrification enhancement tools. Here, we evaluate the factors affecting the potential of denitrifying bioreactors to improve stream health and ecosystem services. The performance of bioreactors and the structure and functioning of stream biotic communities are linked by environmental parameters like dissolved oxygen and nitrate-nitrogen concentrations, dissolved organic carbon availability, flow and temperature regimes, and fine sediment accumulations. However, evidence of bioreactors' ability to improve waterway health and ecosystem services is lacking. To improve the potential of bioreactors to enhance desirable stream ecosystem functioning, future assessments of field-scale bioreactors should evaluate the influences of bioreactor performance on ecological indicators such as primary production, organic matter processing, stream metabolism, and invertebrate and fish assemblage structure and function. These stream health impact assessments should be conducted at ecologically relevant spatial and temporal scales. Bioreactors have great potential to make significant contributions to improving water quality, stream health, and ecosystem services if they are tailored to site-specific conditions and implemented strategically with land-based and stream-based mitigation tools within watersheds. This will involve combining economic, logistical, and ecological information in their implementation. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.