Monday, April 11, 2011

Do the Mountains Grow?


In 1850 the height of Mount Everest ,the tallest peak of the world was surveyed and estimated as 29,002 feet.In a study conducted after a century ,the height was found to be 29,028.Height increased by 26 feet.In the studies involved mountains grow slightly every year .The height of the mountains increases because of some geological process taking place in the depth leading totheir slow and spasmodic uplift .These include folding of rock layers .Uplift of those layers often accompanied faulting or dislocation of rock layers .The term orogeny collectively denotes all process leading to formation of mountains

Sunday, April 10, 2011

Did the Earth always look the same?

Look at the map of the world .Examine the outlines of continets of South America and Africa.Aren't the jutting portions of South America suiting the western portion of Africa like a jigsaw puzzle?Can these two be joined?About 90 years ago a German scientist called Alfred Wegner proved that South America and Africa were once joined together .Wegner knew that there is similarity between rock strata and plant fossils of the continents of South America and Africa.He came to the conclusion that at some remote time,these two continents had been connected ,also on the basis of several other evidences he noted.He propounted the 'Continental Drift Theory'.According to this theory ,it was surmised that all the present continents had been united to a single land mass he named 'Pangaea',surrounded by"Panthalassa'an ancestral primitive ocean.Later this single continent disintegrated and drifted into different continents as we see them today.

Read More

SIGNS, SYMPTOMS, AND STAGES OF ALZHEIMER’S DISEASE


Alzheimer’s Disease 

SIGNS, SYMPTOMS, AND STAGES OF ALZHEIMER’S DISEASE


Alzheimer's Stages, Causes & Risk Factors
Alzheimer’s disease is a disorder that affects millions of older adults and causes more worry for people over 55 years of age than any other condition. Suspecting you or a loved one may be exhibiting signs and symptoms of Alzheimer’s disease can be a stressful and emotional experience for everyone involved. Of course, even if your family history includes Alzheimer’s disease and you find yourself forgetting things, it doesn’t necessarily mean you have this disease. Even when you fear the worst, it is important to share your concerns and seek expert advice. The earlier you recognize the symptoms of Alzheimer’s disease and seek help, the better your chances of getting the care you need and maximizing your quality of life.

What is Alzheimer’s disease?

Alzheimer’s disease is the most common form ofdementia,a serious brain disorder that impacts daily living through memory loss and cognitive changes. Although not all memory loss indicates Alzheimer’s disease, one in ten people over 65 years of age, and over half of those over 85 have Alzheimer’s disease. Currently, 26 million people worldwide have this dementia, and over 15 million Americans will be affected by the year 2050.
Symptoms of Alzheimer’s disease usually develop slowly and gradually worsen over time, progressing from mild forgetfulness to widespread brain impairment. Chemical and structural changes in the brain slowly destroy the ability to create, remember, learn, reason, and relate to others.  As critical cells die, drastic personality loss occurs and body systems fail.

Who is at risk of Alzheimer’s disease?

  • The primary risk factors of Alzheimer’s are age, family history, and genetics. However, there are other risk factors that you can influence. Maintaining a healthy heart and avoiding high blood pressure, heart disease, stroke, diabetes, and high cholesterol can decrease the risk of Alzheimer’s. Watch your weight, avoid tobacco and excess alcohol, stay socially connected, and exercise both your body and mind.
  • Early-onset Alzheimer’s affects patients under the age of 65. This relatively rare condition is seen more often in patients whose parents or grandparents developed Alzheimer’s disease at a young age, and is generally associated with three specific gene mutations (the APP gene found on chromosome 21, the PSI gene on chromosome 12, and the PS2 gene on chromosome 1).
Read More