Monday, August 31, 2009

Symptoms of stomach cancer

In most cases symptoms of stomach cancer are not easy to find out. As the cancer grows to a stage, the most common symptoms are:
uneasiness in the stomach area
Feeling full or overstuffed after a small meal
sickness and vomiting
Weight loss

Studies have found the following risk factors for stomach cancer:

Age: Most people with this disease are 72 or older.

Sex: Men are more likely than women to develop stomach cancer.

Race: Stomach cancer is more common in Asian, Pacific Islander, Hispanic, and African Americans than in non-Hispanic white Americans.

Diet: Studies suggest that people who eat a diet high in foods that are smoked, salted, or pickled may be at increased risk for stomach cancer. On the other hand, eating fresh fruits and vegetables may protect against this disease.

Helicobacter pylori infection: H. pylori is a type of bacteria that commonly lives in the stomach. H. pylori infection increases the risk of stomach inflammation and stomach ulcers. It also increases the risk of stomach cancer, but only a small number of infected people develop stomach cancer.

Friday, August 28, 2009

Body mass index

Various methods are used to determine if someone’s weight has increased his or her health risks. Some are based on the relationship between height and weight; others are based on measurements of body fat. The most commonly used method today is the body mass index (BMI). BMI is an index of weight adjusted for the height of an individual.

BMI can be used to screen for both overweight and obesity in adults. It is the measurement of choice for many obesity researchers and other health professionals, as well as the definition used in most published information on overweight and obesity. BMI is a calculation based on height and weight, and it is not gender-specific in adults. BMI does not directly measure percentage of body fat, but it is a more accurate indicator of overweight and obesity than relying on weight alone.BMI is calculated by dividing a person’s weight in kilograms by height in meters squared. The mathematical formula is “weight (kg)/height (m²).”

Tuesday, August 25, 2009

Best Tips for Eating Healthy when you are eating out.

  • As a beverage choice, ask for water or order fat-free or low-fat milk, unsweetened tea, or other drinks without added sugars.
  • Ask for whole wheat bread for sandwiches.
  • In a restaurant, start your meal with a salad packed with veggies, to help control hunger and feel satisfied sooner.
  • Ask for salad dressing to be served on the side. Then use only as much as you want.
  • Choose main dishes that include vegetables, such as stir fries, kebobs, or pasta with a tomato sauce.
  • Order steamed, grilled, or broiled dishes instead of those that are fried or sautéed.
  • Choose a “small” or “medium” portion. This includes main dishes, side dishes, and beverages.
  • Order an item from the menu instead heading for the “all-you-can-eat” buffet.
  • If main portions at a restaurant are larger than you want, try one of these strategies to keep from overeating:
  • Order an appetizer or side dish instead of an entrée.
  • Share a main dish with a friend.
  • If you can chill the extra food right away, take leftovers home in a “doggy bag.”
  • When your food is delivered, set aside or pack half of it to go immediately.
  • Resign from the “clean your plate club” – when you’ve eaten enough, leave the rest.
  • To keep your meal moderate in calories, fat, and sugars:
  • Ask for salad dressing to be served “on the side” so you can add only as much as you want.
  • Order foods that do not have creamy sauces or gravies
  • Add little or no butter to your food.
  • Choose fruits for dessert most often.
  • On long commutes or shopping trips, pack some fresh fruit, cut-up vegetables, low-fat string cheese sticks, or a handful of unsalted nuts to help you avoid stopping for sweet or fatty snacks.

Monday, August 17, 2009

Geologic Hazards

The geologic processes that formed the spectacular landscapes of many national parks remain active today, and can be hazardous to park visitors, staff, infrastructure, and neighbors. Potentially hazardous processes include volcanic eruptions and other geothermal related features, earthquakes, landslides and other slope failures, mudflows, sinkhole collapses, snow avalanches, flooding, glacial surges and outburstfloods, tsunamis, and shoreline movements.

What are Geologic Hazards?
Geohazards are any geological or hydrological process that poses a threat to people and/or their property.

Avalanche
• Masses of rock or ice that fall or slide suddenly under the force of gravity.
Earthquake
• A sudden ground motion or vibration of the Earth. Produced by a rapid release of stored-up energy along an active fault.
Epicenter
• The point on the Earth’s surface located directly above the focus of an earthquake
Eruption
• Occurs when solid, liquid or gaseous volcanic materials are ejected into the Earth’s atmosphere or surface by volcanic activity. Eruptions may occur as quiet lava flows or violent explosive events.
Lava
• Magma that reaches the Earth’s surface through a volcanic eruption. When cooled and solidified, forms extrusive (volcanic) igneous rock.
Magma
• Molten rock. Magma may be completely liquid or a mixture of liquid rock, dissolved gases and crystals. Molten rock that flows out onto the Earth’s surface is called lava.
Mass wasting
• Movement of rock and soil down slope under the influence of gravity.
Volcano
• The solid structure created when lava, gases, and hot particles escape to the Earth's surface through vents. Volcanoes are usually conical. A volcano is "active" when it is erupting or has erupted recently. Volcanoes that have not erupted recently but are considered likely to erupt in the future are said to be "dormant." A volcano that has not erupted for a long time and is not expected to erupt in the future is "extinct."
Tsunami (plural tsunami)
• A vast sea wave caused by the sudden dropping or rising of a section of the sea floor following an earth- quake. Tsunami may be as much as 30 meters high and 200 kilometers long, may move as fast as 250 kilometers an hour, and may continue to occur for as long as a few days.

Wednesday, August 12, 2009

What is magnetosphere?

A magnetosphere is that area of space, around a planet, that is controlled by the planet's magnetic field. The shape of the Earth's magnetosphere is the direct result of being blasted by solar wind. It prevents most of the particles from the Sun, carried in the solar wind, from hitting the Earth. The Sun and other planets have magnetospheres, but the Earth has the strongest one of all the rocky planets. The Earth's magnetosphere is a highly dynamic structure that responds dramatically to solar variations. Life on Earth developed and is sustained under the protection of this variable magnetosphere.

Sunday, August 09, 2009

Indo-Pacific Humpback Dolphins

Indo-Pacific Humpback Dolphins are characterised by a robust and medium sized body with a short, slightly recurved and triangular-shaped dorsal fin. Individuals from the western part of the species' range have a prominent dorsal ridge forming part the base of the dorsal fin. However, this ridge is not present in Australian animals.

Colouration is uniformly grey, with flanks shading to off-white. Age related changes include a loss of grey colour (shading to white or pinkish) and increased ventral spotting in older animals.

In Australian waters, male Indo-Pacific Humpback Dolphins are recorded to attain lengths of 2.62 m, while females have measured up to 2.6 m. The age and length at physical maturity of South African animals are 13-14 years and 2.58-2.74 m respectively. The maximum lengths and weights recorded in South African animals are 2.7 m and 260 kg for males, and 2.4 m and 170 kg for females.

Adult Indo-Pacific Humpback Dolphins may be found singly or in pairs, while immature individuals tend to associate with groups containing more than one adult. Group size is generally four to seven, but may be as large as 25. Larger Indo-Pacific Humpback Dolphin groups are comprised of all age classes, with adults representing between one half and two thirds of the group.

Goodwin indicated that humpback dolphins show strict female philopatry (stay in the area they were born). However Atkins and Atkins were less certain about the state of philopatry in Richards Bay, KwaZulu-Natal, South Africa, but stated that a small proportion of the animals could be considered resident.

Wednesday, August 05, 2009

The Tree-kangaroos


Lucky you are if you come across a tree-kangaroo in the forest and actually get to see it! Often, the only evidence of a tree-kangaroo's presence is the sudden crash of leaves and branches followed by a thud as the very shy tree-kangaroo jumps from its lofty hiding spot and flee into the bush. Some tree-kangaroo sightings are simply that of a long, brown furry tail disappearing into the undergrowth.

The Wet Tropics is home to Lumholtz's and Bennett's Tree-kangaroos. Both stand no more than 60cm (2 feet) tall but their tails are almost a meter (3 feet) long. They spend most of their time in the tree canopy feeding on leaves and fruits.

The Lumholtz's Tree-kangaroo

Lumholtz's Tree-kangaroo (Dendrolagus lumholtzi) occurs mostly at high altitudes between Kirrama (in the southern Wet Tropics area) to Mt Spurgeon (in the northern Wet Tropics but south of the Daintree River). Generally solitary animal, small groups of up to four can sometimes be seen. A single young is produced and there appears to be no specific breeding season. It is nocturnal and spends the day crouched on a branch sleeping.


The Bennett's Tree-kangaroo

A little larger than Lumholtz's Tree-kangaroo is the Bennett's Tree-kangaroo (Dendrolagus bennettianus). It resides at high and low altitudes north of the Daintree River in an area of only about 70km by 50km (44 miles by 31 miles).