Tuesday, May 24, 2011

Global Changes in Wind Speed and Wind Height

The changes precipitated by the accumulation of greenhouse gases within the global environment are not limited to change in temperature, but are, in fact, many and diverse.  The overarching range of effects that are a direct result of increased concentrations of greenhouse gases is referred to as climate change.  It appears that certain changes in the world's oceans are directly related to climate change.  We have already examined some of these influences including the rise in temperature and the increasing acidity of the world's oceans. 

In a recent report from the laboratory of Dr. I.R. Young and his colleagues from the Swinburne University of Technology at Melbourne, Victoria, Australia, it has been established that there is a trend towards increases in oceanic wind speed and wave height.  These findings are based on satellite-derived data using a variety of measuring devices including altimeters, sophisticated radar equipment, etc.  The advantage of using this type of instrumentation is that the scope of investigation is global in scale.

Oceanic wind speed and wave height are involved in the maintenance of the flow of energy from the atmosphere to the ocean and are involved in upper-ocean mixing.  In the analysis of the data, Young and his associates used a database that contained information collected over a twenty-three year interim.  The authors of this study caution that on account of the relatively brief interval of time encompassed by these data, they cannot determine if this trend will continue to increase or accelerate into the future.

On account of the importance of these changes in terms of their possible impact on the global climate system, it would be judicious to extend the lifetime of this kind of study into the future.

Wednesday, May 11, 2011

The Problem of Weight Control

It has been an oft-stated observation that obesity has become a major public health issue in the United States.  It is widely accepted that the reasons for this problem are multi-faceted, but a high fat diet together with insufficient exercise probably contributes significantly to this issue.  Since this problem has reached national attention, there are increased efforts on the part of scientists to more fully understand the biological processes that underlie weight control.

Ghrelin is a peptide – a peptide is a small protein – hormone found in the stomach that is known to stimulate weight gain in vertebrates.  Furthermore, it has been established that an enzyme, ghrelin-O-acyltransferase (GOAT) is necessary to activate ghrelin.  Doctor Brad P. Barnett and his colleagues from the Department of Pharmacology and Molecular Sciences at the John Hopkins University School of Medicine in Baltimore, Maryland have studied the process of ghrelin-mediated weight control in considerable detail using the mouse animal model.

Doctor Barnett and his team have successfully synthesized a peptide, GO-CoA-Tat, that is similar in structure to ghrelin and binds to GOAT; the result of this binding is the inhibition of the activity of the enzyme GOAT.  When mice were treated with this synthetic peptide, they became more tolerant of glucose and weight gain actually diminished.

This is an important finding for a number of reasons.  It helps elucidate the metabolic processes involved in weight control, and this approach may prove to be of therapeutic value, especially to those individuals whose obesity is difficult to treat by any other means.