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Skin Temperature: The Temperature at the outer surface of the body.

Constant Temperature Anemometry: A Tool to Study Turbulent Boundary Layer Flow

JoVE 10455

Source: Xiaofeng Liu, Jose Roberto Moreto, and Jaime Dorado, Department of Aerospace Engineering, San Diego State University, San Diego, California

A boundary layer is a thin flow region immediately adjacent to the surface of a solid body immersed in flow field. In this region, viscous effects, such as the viscous shear stress, dominate,…

 Aeronautical Engineering

Conducting Reactions Below Room Temperature

JoVE 10224

Source: Laboratory of Dr. Dana Lashley - College of William and Mary

Demonstration by: Matt Smith

When new bonds are formed in the course of a chemical reaction, it requires that the involved species (atoms or molecules) come in very close proximity and collide into one another. The collisions between…

 Organic Chemistry

Regulating Temperature in the Lab: Preserving Samples Using Cold

JoVE 5042

Preservation of laboratory samples, specimens, and reagents using extreme cold is routinely performed in biomedical research labs. This video will discuss some of the methods for keeping laboratory samples cold and will explain the correct cooling method to use for each experimental requirement.

For example, cooling agents, such as ice…

 General Laboratory Techniques


JoVE 10860

Peripheral thermosensation is the perception of external temperature. A change in temperature (on the surface of the skin and other tissues) is detected by a family of temperature-sensitive ion channels called Transient Receptor Potential, or TRP, receptors. These receptors are located on free nerve endings. Those detecting cold temperatures are closer to the surface of the skin than the nerve endings detecting warmth. These thermoTRP channels, while temperature selective, have relatively non-selective cation permeability. There are at least three types of receptors that are activated by cold, of which TRPM8 and TRPA1 are particularly sensitive. TRPM8 has a temperature sensitive range of about 10-26 oC (50-79 oF), and is largely associated with the perception of non-painful, or innocuous, cold. Menthol, a compound found in mint leaves, can also activate this receptor, which helps explain why this flavor is often perceived as cool. When temperatures are low enough to feel painful (i.e., noxious cold), TRPA1 receptors are activated. TRPA1 receptors respond to any temperature lower than 17 oC (~63 oF). There are at least seven receptors that respond to heat. Of these, five respond to temperatures in the innocuous warmth range: TRPM2 (23-38 oC, or ~73-100oF), TRPC5 (26-38 oC, or ~79-

 Core: Biology

Physiology of the Circulatory System- Concept

JoVE 10625


Conditions in the external environment of an organism can change rapidly and drastically. To survive, organisms must maintain a fairly constant internal environment, which involves continuous regulation of temperature, pH, and other factors. This balanced state is known as homeostasis, which describes the processes by which organisms maintain their optimal internal…

 Lab Bio

Sensory Exam

JoVE 10113

Source:Tracey A. Milligan, MD; Tamara B. Kaplan, MD; Neurology, Brigham and Women's/Massachusetts General Hospital, Boston, Massachusetts, USA

A complete sensory examination consists of testing primary sensory modalities as well as cortical sensory function. Primary sensory modalities include pain, temperature, light touch, vibration,…

 Physical Examinations III

Peripheral Vascular Exam

JoVE 10122

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT

The prevalence of peripheral vascular disease (PVD) increases with age and is a significant cause of morbidity in older patients, and peripheral artery disease (PAD) is associated with cardiovascular and cerebrovascular complications.…

 Physical Examinations I


JoVE 10794

Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in the proper synthesis of messenger RNA (mRNA). Regulation of transcription is responsible for the differentiation of all the different types of cells and often for the proper cellular response to environmental signals. In eukaryotes, the DNA is first transcribed into a primary RNA, or pre-mRNA, that can be further processed into a mature mRNA to serve as a template for the synthesis of proteins. In prokaryotes such as bacteria, however, translation of RNA into polypeptides can begin while the transcription is still ongoing, as RNA can be quickly degraded. Transcription can also produce different kinds RNA molecules that do not code for protein, such as microRNAs, transfer RNA (tRNA), and ribosomal RNA (rRNA)—all of which contribute to protein synthesis. With few exceptions, all of the cells in the human body have the same genetic information in them, from neurons in the brain to muscle cells in the heart. So how do cells assume such diverse forms and functions? To a large extent, the answer lies in the regulation of transcription during development of the organism. Specifically, transcriptional regulation plays a central ro

 Core: Biology

Quantitative Strain Mapping of an Abdominal Aortic Aneurysm

JoVE 10480

Source: Hannah L. Cebull1, Arvin H. Soepriatna1, John J. Boyle2 and Craig J. Goergen1

1Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana

2Mechanical Engineering & Materials Science, Washington University in St. Louis, St Louis, Missouri

 Biomedical Engineering

Collagen Hydrogels

JoVE 5786

Collagen is another widely used biomaterial that has found popularity in commercial applications, such as photography. Collagen has more recently been used in tissue engineering applications, by creating hydrogels that provide structure to engineered tissue.

This video introduces collagen as a biomaterial, demonstrates how it is…

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