The P Wave P waves are caused by atrial depolarization. In normal sinus rhythm, the SA node acts as the pacemaker. The electrical impulse from the SA node spreads over the right and left atria to cause atrial depolarization. The P wave contour is usually smooth, entirely positive and of uniform size. The P wave duration is normally less than 0.12 sec and the amplitude is normally less than 0.25 mV. A negative P-wave can indicate depolarization arising from the AV node.

Note that the P wave corresponds to electrical impulses not mechanical atria contraction. Atrial contraction begins at about the middle of the P wave and continues during the PR segment. The PR Segment PR segment is the portion on the ECG wave from the end of the P wave to the beginning of the QRS complex, lasting about 0.1 seconds. The PR segment corresponds to the time between the end of atrial depolarization to the onset of ventricular depolarization. The PR segment is an isoelectric segment, that is, no wave or deflection is recorded. During the PR segment, the impulse travels from the AV node through the conducting tissue (bundle branches, and Purkinje fibers) towards the ventricles. Most of the delay in the PR segment occurs in the AV node. Although the PR segment is isoelectric, the atrial are actually contracting, filling the ventricles before ventricular systole.

The QRS Complex In normal sinus rhythm, each P wave is followed by a QRS complex. The QRS complex represents the time it takes for depolarization of the ventricles. The Q wave is not always present. The R wave is the point when half of the ventricular myocardium has been depolarized. The normal QRS duration range is from 0.04 sec to 0.12 sec measured from the initial deflection of the QRS from the isoelectric line to the end of the QRS complex.

Normal ventricular depolarization requires normal function of the right and left bundle branches. A block in either the right or left bundle branch delays depolarization of the ventricles, resulting in a prolonged QRS duration.

The ST Segment The ST segment represents the period from the end of ventricular depolarization to the beginning of ventricular repolarization. The ST segment lies between the end of the QRS complex and the initial deflection of the T-wave and is normally isoelectric. Although the ST segment is isoelectric, the ventricules are actually contracting.

The T Wave The T wave corresponds to the rapid ventricular repolarization. The wave is normally rounded and positive.

Top 10 actions

Earth Day Canada president Jed Goldberg has identified his top 10 actions to make every day Earth Day.

1. Think before you act. Shopping has become a form of entertainment. While it can be difficult to avoid the seduction of advertising, Goldberg advises to think about what you need, not what you want, before you buy.

2. It’s all about conservation. Goldberg says we need to make the shift from being “consumers” to “prosumers” – producing consumers – to conserve energy and resources. Planting a garden is a great way to start.

3. Go vegetarian one day a week. Meat production has a huge environmental impact. Eating lower on the food chain just one day a week helps to conserve water, reduce greenhouse gas emissions and preserve valuable farmland.

4. Rethink convenience. Goldberg says people do things because they perceive that it’s easier, but easy isn’t always what’s best. Doing things in an environmentally responsible way can ultimately end up being more convenient and much cheaper, too! One example, stop buying bottled water and use tap water instead.

5. Eat and shop locally. Most of our food travels thousands of kilometres to get to our dinner plates. Ditto for our clothing and other consumers goods. Supporting local businesses also helps to build strong local communities.

6. Vote with your dollar. Advertisers and producers are conscious of what consumers want says Goldberg. Take the time to express your opinion to store owners with your wallet and your voice.

7. Use active transportation. Whether it’s walking, cycling or rollerblading, when you use your body to get from A to B instead of a motorized vehicle, you not only get the benefit of improved fitness while reducing your environmental impact, but you get to experience your community.

8. Borrow, don’t buy. Consider renting, borrowing or sharing what you need.

9. Refashion your yard. Instead of trying to achieve the perfect, lawn, why not get rid of the lawn altogether. Plant native shrubs, wildflowers or a vegetable garden. You’ll use fewer resources and free yourself from the lawnmower, too!

10. Use your sphere of influence. Collectively we have a great influence over our politicians, says Goldberg. Engage your family, friends, coworkers and community.

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Our pancreas is affected by diabetes – specifically, Type 2.Our body contains glucose found in the blood stream, which it gets from the sugar in food. Our body uses the glucose, but only when it goes into our blood cells and the insulin released by our pancreas converts it. Insulin production and utilization is difficult for someone who lives with Type 2 diabetes .There is a lot of glucose in the body, but your cells cannot locate them.

The American Diabetes Association has the duty of looking for information regarding this important medical condition. 23.6 million individuals living in America currently have diabetes, and because of this the country is seen as very unhealthy. Ninety percent of this figure has been diagnosed with Type 2 diabetes. Diabetes and the tendency to be overweight usually run in the family. If there is too much glucose in your body, it could result in serious internal organ damage and affect one’s nervous system.

Living with Diabetes

A life with Type 2 diabetes is best lived in a healthy way. Diabetics will find that healthy practices will have a huge effect on them. Simple actions like eating healthy food and exercising are considered as healthy practices. Keeping the levels of your glucose within the appropriate range ensures you stay away from health complications.

To check the levels of blood glucose in your body, you can do the common finger prick test. Physicians say that such a test is comparable to the HbA1c test when tracking the glucose fluctuations in your body. This HbA1c test works by determining how high your glucose levels are and by identifying the blood’s exact glycated hemoglobin percentage. According to results of the A1c tests, people who have diabetes maintain their levels at seven percent. A seven percent maintaining level of a1c, according to the CDC, can dramatically reduce the risks of this disease by around forty percent.

Too-Tight Controls

Many studies in the medical field show that if your a1c levels are below seven percent it could mean a bad thing. People who use insulin and people who have median a1c levels have a higher death risk, according to the Seattle Lancet and Swedish Medical Center’s studies. Other tests maintain that keeping your a1c level at seven percent is still on the healthy side. Accredited endocrinologist Matt Davies shares that seven percent is healthy but it is still important for physicians to consider a patient’s medical history before implementing treatment.

About the Author – Kristina Ridley writes for the bloodless glucose meter blog , her personal hobby blog focused on healthy eating and tips to measure blood glucose levels at home to help people understand early diabetes symptoms.

SmartOne ECG is a self-service consumer portable heart monitor for checking abnormal heart rhythms.

The device can safely measure electrical activities of the heart using one’s finger tips without the need for any trained technician.Upon placing thumbs on the sensor panel of the portable ecg machine,a digital output of the heart rhythm is displayed.If the reading displays any abnormal heart rhythm,it indicates the user the type of abnormal heart rhythm.Atrial fibrillation is an important risk factor for stroke.

According to the WHO,15 million people worldwide suffer a stroke. Of these, 5 million die and another 5 million are left permanently disabled, placing a burden on family and community.