Cite this ArticleCopy Citation | Download Citations
Chao, W., Kolski-Andreaco, A. September 2015 - This Month in JoVE: Measuring Greenhouse Gases and Herbicide Resistance, Bioengineering Bone, and Analyzing Neuromuscular Control with Virtual Reality. J. Vis. Exp. (103), e5748, (2015).
In JoVE Environment, we've had a pretty warm summer in the northern hemisphere, so we can't help but think about all the greenhouse gases in our atmosphere that keep our planet nice and warm. These days, livestock are a major source of greenhouse gas emissions, especially methane. Livestock contribute anywhere from 7 to 18% of global emissions-depending on who you ask. Naturally, climate scientists are interested in controlling enteric methane from livestock. This requires accurate and precise measurement techniques, so Hristov et al. present a method using the Automated Head-Chamber System (AHCS), which monitors methane (CH4) and carbon dioxide (CO2) mass fluxes from the breath of ruminant animals (e.g., cattle). This system produces repeatable and accurate emission results, and can help efforts to curb greenhouse gas emissions.
In JoVE Environment, we're also concerned about herbicide resistance in weeds, which poses a serious threat to food and fiber production. Plants can gain resistance to herbicides through genetic mutations or through enhanced activity of enzymes that metabolize and detoxify chemicals. In order to determine rates of herbicide metabolism in certain weeds, Ma et al. developed an excised leaf assay, which allows them to take experiments from the greenhouse into the lab so they can perform radiolabeled herbicide experiments more efficiently. As more and more plants become resistant to herbicides, this method will be useful for investigating the metabolic basis of herbicide resistance.
In JoVE Bioengineering, one of the ultimate goals of tissue engineering is to regenerate large bone defects using synthetic scaffolds or templates. Most available scaffolds don't allow appreciable cell infiltration or distribution to achieve significant bone regeneration, so Oh et al. have developed a highly porous bone-like template with micro-channels and nanopores. Cells can be seeded into the biogenic templates through capillary action, and grow to confluence within days. This concept can help advance the repair of large bone defects.
In JoVE Behavior, the human neuromuscular junction can be studied using a variety of noninvasive techniques, including electromyography (EMG), 3D motion capture, and transcranial magnetic stimulation. This month, Talkington et al. add the unique aspect of virtual reality to this test battery, and describe a customizable circuit that synchronizes data sampled from all of these techniques.
Multifunctional Setup for Studying Human Motor Control Using Transcranial Magnetic Stimulation, Electromyography, Motion Capture, and Virtual Reality
William J. Talkington, Bradley S. Pollard, Erienne V. Olesh, Valeriya Gritsenko
Department of Human Performance and Applied Exercise Science, Division of Physical Therapy, West Virginia University
Transcranial magnetic stimulation, electromyography, and 3D motion capture are commonly used non-invasive techniques for investigating neuromuscular function in humans. In this paper, we describe a protocol that synchronously samples data generated by all three of these tools along with the unique addition of virtual reality stimulus presentation and feedback.
The Use of an Automated System (GreenFeed) to Monitor Enteric Methane and Carbon Dioxide Emissions from Ruminant Animals
Alexander Hristov1, Joon Oh1, Fabio Giallongo1, Tyler Frederick1, Holley Weeks1, Patrick R Zimmerman2, Michael T. Harper1, Rada A Hristova3, R. Scott Zimmerman2, Antonio F. Branco4
1Department of Animal Science, Pennsylvania State University, 2C-Lock, Inc. Rapid City, SD, 3Color Productions, State College, PA, 4Departamento de Zootecnia, Universidade Estadual de Maringá
Accuracy and precision of the techniques used to measure methane emissions from ruminant animals are critically important for the success of greenhouse gas mitigation efforts. This manuscript describes the principles and operation of an automated system to monitor methane and carbon dioxide mass fluxes from the breath of ruminant animals.
Rong Ma, Joshua J. Skelton, Dean E. Riechers
Department of Crop Science, University of Illinois
This manuscript describes how herbicide metabolism rates can be effectively quantified with excised leaves from a dicot weed, thereby reducing variability and removing any possible confounding effects of herbicide uptake or translocation typically observed in whole-plant assays.
Distinctive Capillary Action by Micro-channels in Bone-like Templates Can Enhance Recruitment of Cells for Restoration of Large Bony Defect
Daniel S Oh1, Alia Koch1, Sidney B. Eisig1, Sahng Gyoon Kim2, Yoon Hyuk Kim3, Do-Gyoon Kim4, Jae Hyuck Shim5
1Oral and Maxillofacial Surgery, Columbia University, 2Endodontics, Columbia University, 3Mechanical Engineering, Kyung Hee University, South Korea, 4Orthodontics, The Ohio State University, 5Pathology, Weill Cornell Medical College
A step-by-step generic process to create a bone-like template with engineered micro-channels is presented. High absorption and retention capabilities of the template are demonstrated by capillary action via micro-channels.
No conflicts of interest declared.