Category Archives: Issues in Science

Mercury – NASA’s Fifth Planetary Conquest

Image of Mercury from previous Messenger missions. From NASA.

After years of planning and development, NASA’s space probe Messenger finally fell into Mercury’s orbit Thursday evening. At 9:10 p.m. of March 17, when the last rocket that projected Messenger shut off and the probe fell into Mercury’s gravity pull, scientists at the control room in John Hopkin’s University started in a round of applause.

Mercury is the fifth planet that NASA spacecrafts have orbited. Mercury is the closest planet to the sun and lacks an atmosphere. This means that Mercury’s surface is super heated by the sun during daytime but drops to hundreds of degrees below freezing at night. Also, without an atmosphere, Mercury’s surface is heavily cratered. The vast temperature different implies that ice could be found inside the craters. The Mercury probe hopes to bring back a year of photography that would help in the research of the creation of Mercury and its composition. With this goal in mind, surveillance of the probe is needed for the next few days. Constant checks on the probe’s health systems, testing of the scientific equipment that is on board is essentially so that the vast amount of data can be collected and  transmitted back to Earth.

This massive project started in 2004 with a budget of $446 million. Hopefully, the probe will bring back valuable data that would useful for planetary scientists to determine the evolution of Mercury.

Messenger also hits close to UBC as one of the Earth and Ocean Science professors, Dr. Catherine Johnson, participated in the project. Dr. Johnson is a participating scientist in the project and hopes to discover the reasons behind Mercury’s magnetic field. The probe Messenger hopefully will gather data that will be of use to Dr. Johnson.

Alzheimer’s Disease

A recent clinical trial on the hit show “Grey’s Anatomy” that was being conducted to find the cure to Alzheimer’s inspired me to write this blog post because I really don’t know much about this disease other than the fact that patients diagnosed with Alzheimer’s suffer from dementia and therefore, wanted to know more about the causes of this disease.

Alzheimer’s is a “progressive and degenerative disease” and is the most common form of dementia. The name for this disease comes from the doctor who first identified the disease: Dr. Alois Alzheimer. According to his research there are two main features to this disease: Plaques and Tangles

Plaques are made of a protein already consisting within the brain called A-beta. A patient with Alzheimer’s generally has more of this protein that accumulates in the brain. They accumulate in such high numbers that it makes it difficult for the enzymes in the brain whose job is to get rid of this protein overwhelming the whole system. Over time as they accumulate they condense into plaques that are toxic.  Researchers believe that these A-beta proteins somehow change the genetic code of the tau protein thereby promoting development of “Tangles”.

Tangles as mentioned before are made of tau protein. These are located in the nerve cells and perform key duties such as self-repair of the nervous system as well as maintaining a transport system within the nerve cells. However after these are modified by the A-beta protein they tend to pile up and create tangles. By creating these tangles the transport system of the cells is disrupted and therefore the cell dies.

The toxic plaques along with the tangles leads to the slow degeneration of cells in the brain, thereby causing the brain to shrink as seen in the following picture.

"Normal Aged brain vs Alzheimer's patient"

I hope to look into more research that has been done on the purpose of the A-beta protein as well as other further research into how doctors might proceed to deal with this disease in the future. Until then I will direct you to the following link that has more information on Alzheimer’s Disease.

Less and Less Baby Polar Bears with Melting Arctic Ice

We all know of the strong correlation between changes in the environment and the polar bears,but a recent study suggests that the population of this species, Ursus maritimus, could be in real danger with the decline of Arctic sea ice specifically in our country’s Hudson Bay.

Source: Flickr

Article published on February 8th, 2011 in Nature Communications outlines a study conducted by Peter K. Molnar et al. from the University of Alberta who used mechanistic models to predict changes in litter size of cub polar bears for pregnant females in the western Hudson Bay population under expected changes in sea ice.

Sea ice is vital for the polar bears because during the winter feeding season they rely on the solid floes to take them near the waters where there are lots of food source – seals. But with temperatures rising and early breakup of the ice sheets, the bears are forced ashore sooner than in the past. Moreover, “on shore, there is no food available for them,” as the lead author of the study puts it. Thus the bears, particularly females of reproductive age, are storing up less energy for the months that they have to hibernate during pregnancy.

The researchers found that ~28% of pregnant females already failed to reproduce for energetic reasons during the 1990s. Using mechanistic models, they predicted that if spring sea ice break-up happens 1 month earlier than during the 1990s – 40-73% of pregnant female polar bears could fail to reproduce, and if the break-up happens 2 month earlier55-100% could fail. On a global perspective, the study states that a similar litter size decline trend may be found in over 1/3 of the polar bear population.

What’s even more discouraging is that “the litter size predictions provided in this study serve as another indicator that the western Hudson Bay population will probably not remain viable under predicted climatic conditions” as the article states.

Heart wenching video that hits home of malnourished  mother polar bear and starving cubs as an example of the conditions that polar bears are and will be facing in the future with current climate change conditions. A Warming Climate Takes its Toll on the Polar Bears of Hudson Bay by Daniel J. Cox