California Institute of Technology

10 articles published in JoVE

Dry Oxidation and Vacuum Annealing Treatments for Tuning the Wetting Properties of Carbon Nanotube Arrays

JoVE 50378 4/15/2013

Graduate Aeronautical Laboratories, California Institute of Technology

This article describes a simple method to fabricate vertically aligned carbon nanotube arrays by CVD and to subsequently tune their wetting properties by exposing them to vacuum annealing or dry oxidation treatment.

Bringing the Visible Universe into Focus with Robo-AO

JoVE 50021 2/12/2013

Christoph Baranec^1,2, Reed Riddle¹, Nicholas M. Law³, A.N. Ramaprakash⁴, Shriharsh P. Tendulkar², Khanh Bui¹, Mahesh P. Burse⁴, Pravin Chordia⁴, Hillol K. Das⁴, Jack T.C. Davis¹, Richard G. Dekany¹, Mansi M. Kasliwal⁵, Shrinivas R. Kulkarni^1,2, Timothy D. Morton², Eran O. Ofek⁶, Sujit Punnadi⁴

¹Caltech Optical Observatories, California Institute of Technology, ²Department of Astronomy, California Institute of Technology, ³Dunlap Institute for Astronomy and Astrophysics, University of Toronto, ⁴Inter-University Centre for Astronomy & Astrophysics, ⁵Observatories of the Carnegie Institution for Science, ⁶Benoziyo Center for Astrophysics, Weizmann Institute of Science

Light from astronomical objects must travel through the earth's turbulent atmosphere before it can be imaged by ground-based telescopes. To enable direct imaging at maximum theoretical angular resolution, advanced techniques such as those employed by the Robo-AO adaptive-optics system must be used.

Quantitatively Measuring In situ Flows using a Self-Contained Underwater Velocimetry Apparatus (SCUVA)

JoVE 2615 10/31/2011

Kakani Katija¹, Sean P. Colin^2,3, John H. Costello^3,4, John O. Dabiri⁵

¹Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, ²Environmental Science and Marine Biology, Roger Williams University, ³Marine Biology Laboratory, Whitman Center, ⁴Department of Biology, Providence College, ⁵Departments of Aeronautics and Bioengineering, California Institute of Technology

This protocol provides instructions on how to use a self-contained underwater velocimetry apparatus (SCUVA), which is designed for quantification of in situ animal-generated flows. In addition, this protocol addresses challenges posed by field conditions, and includes operator motion, predicting position of animals, and orientation of SCUVA.

High Throughput Screening of Fungal Endoglucanase Activity in Escherichia coli

JoVE 2942 8/13/2011

Mary F. Farrow¹, Frances H. Arnold²

¹Department Of Chemistry and Chemical Engineering, California Institute of Technology, ²Chemistry and Chemical Engineering, California Institute of Technology

We describe a low cost, high throughput method to screen for fungal endoglucanase activity in E. coli. The method relies on a simple visual readout of substrate degradation, does not require enzyme purification, and is highly scalable. This allows for the rapid screening of large libraries of enzyme variants.

Assessment of Motor Balance and Coordination in Mice using the Balance Beam

JoVE 2376 3/10/2011

Tinh N. Luong*, Holly J. Carlisle*, Amber Southwell, Paul H. Patterson

Department of Biology, California Institute of Technology

Deficits in fine motor coordination can be assessed with the balance beam test. Performance on the beam is quantified by the speed at which the beam is traversed and the number of times the mouse slips on the beam.

Electron Cryotomography of Bacterial Cells

JoVE 1943 5/06/2010

Songye Chen¹, Alasdair McDowall^1,2, Megan J. Dobro¹, Ariane Briegel^1,2, Mark Ladinsky^1,2, Jian Shi², Elitza I. Tocheva¹, Morgan Beeby^1,2, Martin Pilhofer^1,2, H. Jane Ding¹, Zhuo Li^1,2, Lu Gan¹, Dylan M. Morris¹, Grant J. Jensen^1,2

¹Division of Biology, California Institute of Technology - Caltech, ²Howard Hughes Medical Institute, California Institute of Technology - Caltech

We illustrate here how to use electron cryotomography (ECT) to study the ultrastructure of bacterial cells in near-native states, to "macromolecular" (~4 nm) resolution.

Live Dissection of Drosophila Embryos: Streamlined Methods for Screening Mutant Collections by Antibody Staining

JoVE 1647 12/29/2009

Hyung-Kook (Peter) Lee, Ashley P. Wright, Kai Zinn

Division of Biology, California Institute of Technology

We describe a streamlined protocol for generating "fillet" preparations of Drosophila embryos of specific genotypes. This protocol allows efficient execution of a variety of genetic screens. It also allows excellent visualization of structures in the late embryo.

Extracting DNA from the Gut Microbes of the Termite (Zootermopsis Angusticollis) and Visualizing Gut Microbes

JoVE 195 5/28/2007

Eric Matson, Elizabeth Ottesen, Jared Leadbetter

Department of Environmental Science and Engineering, California Institute of Technology - Caltech

This video illustrates the technique for extracting DNA from the species of microbes resident in the termite hindgut. The preparation of a wet mount slide, which is useful for visualizing the gut microbial community is also illustrated, and a tour through the species-rich gut environment is given.

Investigating the Microbial Community in the Termite Hindgut - Interview

JoVE 196 5/28/2007

Jared Leadbetter

Department of Environmental Science and Engineering, California Institute of Technology - Caltech

Jared Leadbetter explains why the termite-gut microbial community is an excellent system for studying the complex interactions between microbes. The symbiotic relationship existing between the host insect and lignocellulose-degrading gut microbes is explained, as well as the industrial uses of these microbes for degrading plant biomass and generating biofuels.

Layers of Symbiosis - Visualizing the Termite Hindgut Microbial Community

JoVE 197 5/28/2007

Jared Leadbetter

Department of Environmental Science and Engineering, California Institute of Technology - Caltech

Jared Leadbetter takes us for a nature walk through the diversity of life resident in the termite hindgut - a microenvironment containing 250 different species found nowhere else on Earth. Jared reveals that the symbiosis exhibited by this system is multi-layered and involves not only a relationship between the termite and its gut inhabitants, but also involves a complex web of symbiosis among the gut microbes themselves.