Relation between presence‐absence of a visible nucleoid and metabolic activity in bacterioplankton cells
- Joon-Won Choi, E. Sherr, B. Sherr
- Environmental Science, Biology
- 1 September 1996
Results show that some bacteria without visible nucleoids are capable of becoming NV cells, and thus have DNA in a nucleoid region not detectable with the method used here.
Effects of Fixation on Cell Volume of Marine Planktonic Protozoa
- Joon-Won Choi, D. Stoecker
- Biology, Environmental ScienceApplied and Environmental Microbiology
- 1 July 1989
Differential effects of fixation on cell volumes may result in an underestimation of the biomass of certain protozoan taxa in natural samples.
Effects of Temperature on Two Psychrophilic Ecotypes of a Heterotrophic Nanoflagellate, Paraphysomonas imperforata
- Joon-Won Choi, Francesc Peters
- Environmental ScienceApplied and Environmental Microbiology
- 1 February 1992
Two different psychrophilic types of the heterotrophic nanoflagellate Paraphysomonas imperforata were isolated from Newfoundland coastal waters and the Arctic Ocean and it is concluded that they are ecotypes adapted to specific environmental conditions.
Dead or alive? A large fraction of ETS-inactive marine bacterioplankton cells, as assessed by reduction of CTC, can become ETS-active with incubation and substrate addition
- Joon-Won Choi, B. Sherr, E. Sherr
- Environmental Science, Biology
- 9 August 1999
Under conditions of increased temperature and high concentration of organic substrate, a large proportion of the apparently 'inactive' bacteria can become highly ETS-active within a day, suggesting that these cells are in fact alive, and are capable of attaining significant metabolic activity.
Paraphysomonas imperforata (Protista, Chrysomonadida) under different turbulence levels: feeding, physiology and energetics
- Francesc Peters, Joon-Won Choi, T. Gross
- Environmental Science
- 25 April 1996
Flagellates increased in numbers and decreased in size at all turbulence intensities as well as in nonturbulence treatments, probably as an adaptation to an environment with lower food concentration than the stock cultures.
The Dynamic Nature of Protistan Ingestion Response to Prey Abundance
- Joon-Won Choi
- Environmental Science
- 1 March 1994
In light of the dynamic nature of protistan ingestion response to prey abundance, short incubation, which minimizes the physiological change, and careful handling, which prevents the possible physical stress, should be employed in order to avoid underestimation of in situ ingestion rates.
The effects of algal density on growth of heterotrophic microflagellates
- Joon-Won Choi
- Environmental Science
- 1 September 1988
The major role oi heterotrophic nanoilagellates in the ocean is generally thought to be as grazers oi bacteria, but they may also play an important role as grazers oi photoautotrphs. The goal oi the…
An Experimental Study about The Effect of Solid Particle Seeding on Thermal Characteristics of Hydrogen Flame
- Jung-Ju Kim, S. Baek, H. Kim, Joon-Won Choi
- Engineering
- 2002
From the view of the environmental protection against the use of fossil fuels, a great of efforts have been exerted to find an alternative energy source. Hydrogen may become an alternative However…
Effects of CO2on Heat Transfer from Oxygen-Enriched Hydrogen Flame
- C. Lee, Joon-Won Choi, S. Baek
- Engineering
- 1 August 2004
Effects of Addition of Carbon Dioxide on Thermal Characteristics in Oxygen-Enriched Hydrogen Flame
- C. Lee, S. Baek, Joon-Won Choi
- Physics, Engineering
- 15 May 2005
An experimental study has been conducted to evaluate the effects of CO2 addition on thermal behavior in oxygen-enriched hydrogen flame. Experiments were performed on flames stabilized by a co-flow…