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Duplicating the Conditions of the Body

SmartTrak® 100 Mass Flow Controller

For centuries, folklore has recognized that garlic is a cure-all, preventing heart disease, high cholesterol, diabetes, and high blood pressure. With the help of Sierra, Dr. David Kraus, a seasoned Sulfide Biologist, and his team at the University of Alabama at Heart Pulse Birmingham have demonstrated just how garlic derived compounds produce Hydrogen Sulfide (H2S) and can relax the vessels in our bodies—coined by biologists as vasorelaxation.

Early in his experiments, Dr. Kraus delivered N2 and air with a system that rigged up gas cylinders, each with a specific gas content. But switching cylinders and maintaining exact oxygen concentrations proved difficult and time-consuming.


In 2005, Dr. Kraus decided to make a much needed change. Rakesh Patel, an experienced vascular biologist, advised Dr. Kraus to give Sierra’s SmartTrak® 100 a try. He installed SmartTrak 100s in a manifold system that simultaneously controlled 8 organ baths. Through a series of pipes, the 100s precisely controlled the N2 and air levels delivered to each of the plasma rich organ baths which contained ¼-inch thick rat aorta. Each 100 bubbled a mixture of N2 and air, each containing 5% CO2, to maintain a specific O2 concentration from 30-50 micro-mole.

Amazingly, when small amounts of H2S were injected into these vessel baths, Dr. Kraus observed the rat aorta relaxing, not constricting. Dr. Kraus and his team proved that H2S, a compound found in garlic, does indeed help relax the smooth muscles in our bodies. These results further prove that by eating garlic, we can decrease the risk of cardiovascular disease, diabetes, and stroke.

For Dr. Kraus, the accuracy of the SmartTrak 100 is essential for the success of his experiments. The 100 precisely "duplicates the conditions of the body", says Dr. Kraus, exposing his test tissue to the same O2 pressure and temperature that the body experiences. To achieve publishable results, Dr. Kraus must isolate the effects of H2S on his test tissues by eliminating the experimental variables. He must be certain that he is observing the effects of H2S on the body, not the effects of an external variable. So far, Dr. Kraus has been very pleased that the SmartTrak has helped "eliminate variance" in his experiments. He excitedly remarks that he has observed “vasorelaxation in the range of the body”--vessels relaxing under the exact conditions experienced by the body.

In November of 2007, Dr. Kraus and his team published their findings in the Proceedings of the National Academy of Science Journal in the article, "Hydrogen Sulfide Mediates the Vasoactivity of Garlic"

Here's what makes Sierra's SmartTrak 100 an ideal choice:
  • Patented, inherently linear Laminar Flow Element (LFE) design
  • Provides smooth and flexible valve performance
  • Pilot Module allows user to switch between ten pre-programmed gases, change setpoint value and source, set zero, span and full scale, modify engineering units, choose output signal...and much more
  • Has more robust electronics than other industry mass flow controllers