Indian boy solves 350-year-old Math problem set by Newton

Lifestyle-City, The Information World

London: A 16-year-old Indian origin schoolboy in Germany has managed to crack puzzles that baffled the world of maths for more than 350 years, it was reported in London Saturday.

Shouryya Ray, from Dresden, has been hailed a genius after working out the problems set by Sir Isaac Newton.

Ray solved two fundamental particle dynamics theories which physicists have previously been able to calculate only by using powerful computers, Daily Mail reported.

 His solutions mean that scientists can now calculate the flight path of a thrown ball and then predict how it will hit and bounce off a wall.

Ray only came across the problems during a school trip to Dresden University where professors claimed they were uncrackable, the newspaper said.

“I just asked myself, ‘Why not?’,” explained Ray.

“I didn’t believe there couldn’t be a solution,” he added.

Ray began solving complicated equations as a six-year-old but says he’s no genius.

After arriving from Kolkata four years ago without any knowledge of the German language, Shouryya is now fluent in the language.

His intelligence was quickly noted in class and he was pushed up two years in school- he is currently sitting his exams early, the Mail said.

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Joint aspiration

The anterior cruciate ligament (ACL)
Joint aspiration

Joint aspiration

Synovial fluid analysis is a series of tests performed on synovial (joint) fluid to help diagnose and treat joint-related abnormalities. To obtain a synovial fluid sample, a needle is inserted into the knee between the joint space. When the needle is in place the synovial fluid is then withdrawn. The sample is sent to the lab for analysis.

Arthrography

Medical- Medicine

What are the limitations of arthrography?

The limitations of arthrography include:

  • Partial tears of the rotator cuff may not be detected with conventional arthrography.
  • Some joint injuries cannot be detected with conventional (x-ray) arthrography including tears of the cartilage which can be found inside and along the edges of some joints, bruising of neighboring bones and injuries to ligaments outside the joint.
  • MR arthrography images the interior of the joint well, but is not as effective as standard MRI in detecting abnormalities of bone and surrounding tissues.

Arthrography

Medical- Medicine

What are the benefits vs. risks?

Benefits

  • Arthrography is particularly effective for detecting tears or lesions of the structures and ligaments of the joints, especially the knee, wrist and elbow, as well as rotator cuff tears or damage from a shoulder dislocation.

Exams involving x-ray imaging:

  • No radiation remains in a patient’s body after an x-ray examination.
  • X-rays usually have no side effects in the diagnostic range.

Exams involving MR imaging:

  • MRI is a noninvasive imaging technique that does not involve exposure to ionizing radiation.
  • MRI enables the discovery of abnormalities that might be obscured by bone with other imaging methods.
  • The contrast material used in MRI exams is less likely to produce an allergic reaction than the iodine-based contrast materials used for conventional x-rays and CT scanning.

Risks

  • Any procedure where the skin is penetrated carries a risk of infection. The chance of infection requiring antibiotic treatment appears to be less than one in 1,000.

Exams involving x-ray imaging:

  • There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis far outweighs the risk.
  • Patients who have known allergies to iodine may have an adverse reaction to the contrast material. Because the contrast material is put in a joint and not a vein, allergic reactions are very rare, although in some cases, mild nausea to severe cardiovascular complications may result.
  • Women should always inform their physician or x-ray technologist if there is any possibility that they are pregnant. See the Safety page for more information about pregnancy and x-rays.
  • The effective radiation dose for this procedure varies. See the Safety page for more information about radiation dose.

Exams involving MR imaging:

  • The MRI examination poses almost no risk to the average patient when appropriate safety guidelines are followed.
  • If sedation is used there are risks of excessive sedation. The technologist or nurse monitors your vital signs to minimize this risk.
  • Although the strong magnetic field is not harmful in itself, implanted medical devices that contain metal may malfunction or cause problems during an MRI exam.
  • There is a very slight risk of an allergic reaction if contrast material is injected. Such reactions usually are mild and easily controlled by medication. If you experience allergic symptoms, a radiologist or other physician will be available for immediate assistance.
  • Nephrogenic systemic fibrosis is currently a recognized, but rare, complication of MRI believed to be caused by the injection of high doses of gadolinium contrast material in patients with very poor kidney function.

A Word About Minimizing Radiation Exposure

Special care is taken during x-ray examinations to use the lowest radiation dose possible while producing the best images for evaluation. National and international radiology protection councils continually review and update the technique standards used by radiology professionals.

State-of-the-art x-ray systems have tightly controlled x-ray beams with significant filtration and dose control methods to minimize stray or scatter radiation. This ensures that those parts of a patient’s body not being imaged receive minimal radiation exposure.

Arthrography

Medical- Medicine

Who interprets the results and how do I get them?

A radiologist, a physician specifically trained to supervise and interpret radiology examinations, will analyze the images and send a signed report to your primary care or referring physician, who will discuss the results with you.

Follow-up examinations are often necessary, and your doctor will explain the exact reason why another exam is requested. Sometimes a follow-up exam is done because a suspicious or questionable finding needs clarification with additional views or a special imaging technique. A follow-up examination may be necessary so that any change in a known abnormality can be detected over time. Follow-up examinations are sometimes the best way to see if treatment is working or if an abnormality is stable over time.

Arthrography

Medical- Medicine

How is the procedure performed?

Iodine contrast material has been injected into the shoulder joint - this is a shoulder arthrogram.

Iodine contrast material has been injected into the shoulder joint - this is a shoulder arthrogram.

This examination is usually done on an outpatient basis.

The patient is positioned on the examination table and x-rays are taken of the joint to be compared later with the arthrograms. If recent x-rays are available, the physician may choose to use these for reference.

Next, the skin around the joint is cleansed with antiseptic and a local anesthetic is injected into the area.

Your physician will numb the area with a local anesthetic.

The area where the needle is to be inserted will be sterilized and covered with a surgical drape.

A needle is then inserted into the joint. The radiologist, a physician specifically trained to supervise and interpret radiology examinations, will use a syringe to drain the joint fluid, which may be sent to a laboratory for analysis. Aspiration is typically performed when an infection is suspected.

The contrast material and sometimes air are injected into the joint space and the needle is removed. Air will not be used if the patient is undergoing MR arthrography. The patient will be asked to move the affected joint to distribute the contrast material throughout the space.

The conventional arthrography exam is usually completed within 30 minutes. Exams involving MRI may take more than one hour.

Arthrography

Medical- Medicine

How does the procedure work?

An x-ray of the right shoulder prior to injection of contrast material.

An x-ray of the right shoulder prior to injection of contrast material.

X-rays are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. Once it is carefully aimed at the part of the body being examined, an x-ray machine produces a small burst of radiation that passes through the body, recording an image on photographic film or a special digital image recording plate.

Different parts of the body absorb the x-rays in varying degrees. Dense bone absorbs much of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x-rays to pass through them. As a result, bones appear white on the x-ray, soft tissue shows up in shades of gray and air appears black.

Until recently, x-ray images were maintained as hard film copy (much like a photographic negative). Today, most images are digital files that are stored electronically. These stored images are easily accessible and are frequently compared to current x-ray images for diagnosis and disease management.

Fluoroscopy uses a continuous or pulsed x-ray beam to create a sequence of images that are projected onto a fluorescent screen, or television-like monitor. When used with a contrast material, which clearly defines the area being examined by making it appear bright white, this special x-ray technique makes it possible for the physician to view joints or internal organs in motion. Still images are also captured and stored either on film or electronically on a computer.

Unlike conventional x-ray examinations and computed tomography (CT) scans, MRI does not depend on ionizing radiation. Instead, while in the magnet, radio waves redirect the axes of spinning protons, which are the nuclei of hydrogen atoms, in a strong magnetic field.

The magnetic field is produced by passing an electric current through wire coils in most MRI units. Other coils, located in the machine and in some cases, placed around the part of the body being imaged, send and receive radio waves, producing signals that are detected by the coils.

A computer then processes the signals and generates a series of images each of which shows a thin slice of the body. The images can then be studied from different angles by the interpreting radiologist.

Frequently, the differentiation of abnormal (diseased) tissue from normal tissues is better with MRI than with other imaging modalities such as x-ray, CT and ultrasound.

Arthrography

Medical- Medicine

What does the equipment look like?

Radiography equipment

Radiography equipment

The equipment typically used for this examination consists of a radiographic table, an x-ray tube and a television-like monitor that is located in the examining room. Fluoroscopy, which converts x-rays into video images, is used to watch and guide progress of the procedure. The video is produced by the x-ray machine and an image intensifier that is suspended over a table on which the patient lies.
The traditional MRI unit is a large cylinder-shaped tube surrounded by a circular magnet. You will lie on a moveable examination table that slides into the center of the magnet.
Some MRI units, called short-bore systems, are designed so that the magnet does not completely surround you; others are open on the sides (open MRI). These units are especially helpful for examining patients who are fearful of being in a closed space and for those who are very obese. Newer open MRI units provide very high quality images for many types of exams; however, open MRI units with older magnets may not provide this same image quality. Certain types of exams cannot be performed using open MRI. For more information, consult your radiologist.
The computer workstation that processes the imaging information is located in a separate room from the scanner.
Other equipment necessary for performing arthrography include a variety of needles, syringes and a water-soluble contrast material.

Arthrography

Medical- Medicine

How should I prepare?

No special preparation is necessary before arthrography. Food and fluid intake do not need to be restricted, unless a sedative will be given.
You should inform your physician of any medications you are taking and if you have any kidney problems or allergies, especially to iodinated contrast materials. Also inform your doctor about recent illnesses or other medical conditions.
Some MRI examinations may require the patient to receive an injection of contrast into the bloodstream. The radiologist or technologist may ask if you have allergies of any kind, such as allergy to iodine or x-ray contrast material, drugs, food, the environment, or asthma. However, the contrast material used for an MRI exam, called gadolinium, does not contain iodine and is less likely to cause side effects or an allergic reaction.
The radiologist should also know if you have any serious health problems or if you have recently had surgery. Some conditions, such as severe kidney disease, may prevent you from being given contrast material for having an MRI.
If you are scheduled to have MR or CT arthrography and have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your physician about being sedated prior to the scheduled examination.
Jewelry and other accessories should be left at home if possible, or removed prior to the MRI scan. Because they can interfere with the magnetic field of the MRI unit, metal and electronic objects are not allowed in the exam room. These items include:
jewelry, watches, credit cards and hearing aids, all of which can be damaged.
pins, hairpins, metal zippers and similar metallic items, which can distort MRI images.
removable dental work.
pens, pocketknives and eyeglasses.
body piercings.
In most cases, an MRI exam is safe for patients with metal implants, except for a few types. People with the following implants cannot be scanned and should not enter the MRI scanning area unless explicitly instructed to do so by a radiologist or technologist who is aware of the presence of any of the following:
internal (implanted) defibrillator or pacemaker
cochlear (ear) implant
some types of clips used on brain aneurysms
some types of metal coils placed within blood vessels
You should tell the technologist if you have medical or electronic devices in your body, because they may interfere with the exam or potentially pose a risk, depending on their nature and the strength of the MRI magnet. Examples include but are not limited to:
artificial heart valves
implanted drug infusion ports
implanted electronic device, including a cardiac pacemaker
artificial limbs or metallic joint prostheses
implanted nerve stimulators
metal pins, screws, plates, stents or surgical staples
In general, metal objects used in orthopedic surgery pose no risk during MRI. However, a recently placed artificial joint may require the use of another imaging procedure. If there is any question of their presence, an x-ray may be taken to detect the presence of and identify any metal objects.
Patients who might have metal objects in certain parts of their bodies may also require an x-ray prior to an MRI. You should notify the technologist or radiologist of any shrapnel, bullets, or other pieces of metal which may be present in your body due to accidents. Dyes used in tattoos may contain iron and could heat up during MRI, but this is rarely a problem. Tooth fillings and braces usually are not affected by the magnetic field but they may distort images of the facial area or brain, so the radiologist should be aware of them.
You may be asked to remove some or all of your clothes and to wear a gown during the exam. You may also be asked to remove jewelry, removable dental appliances, eye glasses and any metal objects or clothing that might interfere with the x-ray images.
Women should always inform their physician and x-ray technologist if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to radiation. If an x-ray is necessary, precautions will be taken to minimize radiation exposure to the baby. See the Safety page for more information about pregnancy and x-rays.
Though MRI does not use ionizing radiation, women should still inform their physician and technologist if they may be pregnant.
Children younger than teenagers may need to be sedated in order to hold still for the procedure. Parents should ask about this beforehand and be made aware of food and drink restrictions that may be needed prior to sedation.
You should plan to have a relative or friend drive you home after your procedure.

Arthrography

Medical- Medicine

What is Arthrography?

Arthrography is medical imaging to evaluate conditions of joints. There are several methods to do this.
Conventional arthrography is the x-ray examination of a joint that uses a special form of x-ray called fluoroscopy and a contrast material containing iodine. Alternate methods of arthrography examinations use magnetic resonance imaging (MRI) or computed tomography (CT).
An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.
Fluoroscopy makes it possible to see bones, joints and internal organs in motion. When iodine contrast is injected into the joint, it fills the entire joint and appears bright white on an arthrogram, allowing the radiologist to assess the anatomy and function of the joint. Although the injection is typically monitored by fluoroscopy, the examination also involves taking radiographs for documentation. The images are most often, but not always, stored or viewed electronically.
MR arthrography also involves the injection of a contrast material into the joint, just like in conventional arthrography, except that the MR contrast material is different and contains gadolinium, which affects the local magnetic field. As in conventional arthrography, the contrast material outlines the structures within the joint and allows them to be evaluated by the radiologist.
MRI uses a powerful magnetic field, radiofrequency pulses and a computer to produce detailed pictures of organs, soft tissues, bone and virtually all other internal body structures. The images can then be examined on a computer monitor, printed or copied to CD. MRI does not use ionizing radiation (x-rays).
CT arthrography uses the same type of contrast material as conventional arthrography and may be supplemented by air to produce a double contrast CT arthrogram. CT makes cross sectional images processed by a computer using x rays.

More advanced stuff

Google Maps API Tutorial

Altitude

Google themselves don’t serve altitude information, so if you want to obtain the altitude, you’ll need to get it from somewhere else.

Here’s a simple example

One place where you can get altitude information is the US Geological Survey Elevation Query. Information about their service can be found here:
gisdata.usgs.gov/XMLWebServices/TNM_Elevation_Service.php

A request looks like this:
http://gisdata.usgs.gov/xmlwebservices2/elevation_service.asmx/getElevation?X_Value=-118.4&Y_Value=36.7&Elevation_Units=METERS&Source_Layer=-1&Elevation_Only=true.

The parameters are:

X_Value Longitude
Y_Value Latitude
Elevation_Units METERS or FEET.
Source_layer You can use this to request data from a specific survey, or use -1 to request the best available data at the location.
Elevation_Only true or false. If you set it false you get information about the data source as well as the elevation data.

The service provides a SOAP interface that returns XML, so you can’t access it directly from Javascript for security reasons. What you have to do is to write a little server script that runs in your own domain. Your Javascript can send a request to your own server, which then sends the request to USGS and returns the reply back to your Javascript client.

I’m not a PHP expert, but I managed to throw together something that works for this purpose. A general purpose relay script would need to be more complicated than this, to avoid the possibility of cross-domain attacks, but I think I can trust the USGS. My PHP code looks like this and returns the data like this:altitude.php?lat=53&lng=-2.

There are two asynchronous steps in this chain, so don’t expect to be able to write a function that returns the altitude of a point. Send the request with GDownloadUrl() and then process the reply in the callback funtion. If you’re sending several requests (e.g. to obtain the profile of a cycle route) you can wrap your call in a function and use it to hold Function Closure so that you can match the replies back to the requests.

The service will return up to 10 decimal places of information, but I suspect that the surveys aren’t accurate to 0.1 nanometres. In my code I just use the integer value.

The service returns the value 0 for open sea. You could therefore use it to distinguish land from sea, but there are a few other points on land where the elevation is also zero, e.g. Elburg in the Netherlands.

The documentation states that the service can return the value -1.79769313486231E+308 if there is no valid data for the requested location, so you might want to filter out such values if you’re drawing an elevation diagram.

In this example I use GDirections to find a route, use the EPoly extension to obtain points at equal distances along that route, use USGS to find the altitude at those points, and use the Google Chart API to plot a chart of those altitudes.

More advanced stuff

Google Maps API Tutorial

GLayers

API v2.130 introduces GLayers, which can be used for displaying the Wikipedia and Panoramio layers to your map.

Google themselves don’t (yet) supply a control for allowing users to switch layers on and off, so I wrote this example

IDs and LMCs

The documented way to specify a particular layer is by using its ID. The official list of IDs is atspreadsheets.google.com/pub?key=p9pdwsai2hDN-cAocTLhnag

In addition to the official list, there are also “com.panoramio.popular”, which omits the Panoramio elements that have the small icons, and there’s “com.youtube.all” which displays the YouTube layer, and there are a few other Wikipedia languages. I don’t intend to test all possible Wikipedia languages: If your favourite language is supported by Wikipedia but isn’t in the official GLayers list, try it anyway.

There’s also an undocumented way to specify a particular layer, by using its LMC. E.g.map.addOverlay(new GLayer(“lmc:panoramio/0”)) is the same as map.addOverlay(new GLayer(“com.panoramio.popular”)).

You can only use IDs that the particular release of the main API code knows about, because the main API code needs to know how to translate the ID into an LMC. In v2.130, the known IDs are “com.panoramio.all”, “com.panoramio.popular” and “org.wikipedia.*”.

When you use an LMC, the main API code doesn’t need to translate it for you, so you can use any LMC for which there is a service.

At the moment, the only LMC that I know about that has service but no ID is “lmc:panoramio/1”, which displays the unpopular Panoramio entries and omits the popular ones.

Viewing the source of maps.google.com reveals the existence of “lmc:youtube”, but the API has no service for it at the moment.

hide() and show()

GLayers support .hide(), .show() and .isHidden().

GLayers don’t support .supportsHide().

More advanced stuff

Google Maps API Tutorial

Arrows

It’s possible to put arrowheads onto polylines by using the Google direction marker triangle icons.

The direction markers have names like “dir_0.png”, “dir_3.png”, up to “dir_117.png”. The numbers indicate the direction in degrees. Only integers that are a multiple of 3 are supported. Only values below 120 degrees are supported, but since the marker has threefold symmetry, it looks the same if rotated back by 120 degrees.

Here’s an example

In the upper polyline of that example, I calculate the bearing between the last two points in the array that’s used to create the polyline, and place the arrowhead, pointing in that direction, over the last point of the polyline.

In the lower polyline of that example, I calulate the bearing between the previous point and the next point to determine a tangent direction.

The Basics

Google Maps API Tutorial

Google Earth Icons

The Google Earth icons are now available on the Google Maps server (so that Google Maps can render KML files that use them). There are four folders of icons

Each of the folders contains 64 icons (some of which are duplicates) named icon0.png to icon64.png

For each icon there’s a main icon image PNG (32 x 32) and a shadow image PNG (59 x 32) in the same folder.
No suitable transparent images, print images or imageMaps seem to be available.

 icon27.png  icon27s.png

These settings are suitable for most of the Google Earth icons:

   Icon.iconSize=new GSize(32,32);
   Icon.shadowSize=new GSize(56,32);
   Icon.iconAnchor=new GPoint(16,32);
   Icon.infoWindowAnchor=new GPoint(16,0);

Here’s an example

Pal2

icon0.png icon1.png icon2.png icon3.png icon4.png icon5.png icon6.png icon7.png
icon8.png icon9.png icon10.png icon11.png icon12.png icon13.png icon14.png icon15.png
icon16.png icon17.png icon18.png icon19.png icon20.png icon21.png icon22.png icon23.png
icon24.png icon25.png icon26.png icon27.png icon28.png icon29.png icon30.png icon31.png
icon32.png icon33.png icon34.png icon35.png icon36.png icon37.png icon38.png icon39.png
icon40.png icon41.png icon42.png icon43.png icon44.png icon45.png icon46.png icon47.png
icon48.png icon49.png icon50.png icon51.png icon52.png icon53.png icon54.png icon55.png
icon56.png icon57.png icon58.png icon59.png icon60.png icon61.png icon62.png icon63.png

Pal3

icon0.png icon1.png icon2.png icon3.png icon4.png icon5.png icon6.png icon7.png
icon8.png icon9.png icon10.png icon11.png icon12.png icon13.png icon14.png icon15.png
icon16.png icon17.png icon18.png icon19.png icon20.png icon21.png icon22.png icon23.png
icon24.png icon25.png icon26.png icon27.png icon28.png icon29.png icon30.png icon31.png
icon32.png icon33.png icon34.png icon35.png icon36.png icon37.png icon38.png icon39.png
icon40.png icon41.png icon42.png icon43.png icon44.png icon45.png icon46.png icon47.png
icon48.png icon49.png icon50.png icon51.png icon52.png icon53.png icon54.png icon55.png
icon56.png icon57.png icon58.png icon59.png icon60.png icon61.png icon62.png icon63.png

Pal4

icon0.png icon1.png icon2.png icon3.png icon4.png icon5.png icon6.png icon7.png
icon8.png icon9.png icon10.png icon11.png icon12.png icon13.png icon14.png icon15.png
icon16.png icon17.png icon18.png icon19.png icon20.png icon21.png icon22.png icon23.png
icon24.png icon25.png icon26.png icon27.png icon28.png icon29.png icon30.png icon31.png
icon32.png icon33.png icon34.png icon35.png icon36.png icon37.png icon38.png icon39.png
icon40.png icon41.png icon42.png icon43.png icon44.png icon45.png icon46.png icon47.png
icon48.png icon49.png icon50.png icon51.png icon52.png icon53.png icon54.png icon55.png
icon56.png icon57.png icon58.png icon59.png icon60.png icon61.png icon62.png icon63.png

Pal5

icon0.png icon1.png icon2.png icon3.png icon4.png icon5.png icon6.png icon7.png
icon8.png icon9.png icon10.png icon11.png icon12.png icon13.png icon14.png icon15.png
icon16.png icon17.png icon18.png icon19.png icon20.png icon21.png icon22.png icon23.png
icon24.png icon25.png icon26.png icon27.png icon28.png icon29.png icon30.png icon31.png
icon32.png icon33.png icon34.png icon35.png icon36.png icon37.png icon38.png icon39.png
icon40.png icon41.png icon42.png icon43.png icon44.png icon45.png icon46.png icon47.png
icon48.png icon49.png icon50.png icon51.png icon52.png icon53.png icon54.png icon55.png
icon56.png icon57.png icon58.png icon59.png icon60.png icon61.png icon62.png icon63.png

The Basics

Google Maps API Tutorial

Using GOverviewMapControl

GOverviewMapControl provides an “overview” map which is linked to the main map.

Here’s an example

Tweaking the Overview map

In versions below v2.93 the following tweaks can be applied directly.
In version v2.93 and above you need to wait for the control code to be loaded from an external module.
See Tweaking GOverviewMapControl in v2.93

Absolute Positioning

Positioning the overview can be achieved by obtaining a reference to the div that contains the overview map and applying styles to it. The “id” of the overview div is created from the “id” of the parent map by appending “_overview”. So if your main map is called “map”, the overview map div will be called “map_overview”.

Applying styles

Once you’ve got a reference to the div, you could apply other styles to it. Those margins on the left and top look rather odd when it’s not in the corner of the page. I guess that the styles might be likely to change in future releases, so the styles that I apply in the example may well need to be changed.

The overview has three nested divs, the outer one has id=”map_overview”. The API styles are:

  • Outer div: width and height set to the requested GSize() or (150,150).
  • Next div: width and height set to the requested GSize() or (150,150), background-color: white, border-top and border-left: “1px solid gray”.
  • Inner div: width and height 9px less than the outer div size, background-color: “rgb(229, 227, 223)”, border: “1px solid gray”, left: “7px”, top: “7px”.

It’s the “left:7px; right:7px” that causes the map to be placed asymmetrically within the div.

In my example, I make the border go all the way round, centre the inner div within the middle div, and change the size of the inner div to be an even number of pixels so that the margins are the same width all the way round.

Accessing the overview GMap2

It is possible to get a reference to the GMap2 that sits inside the GOverviewMapControl, and then use GMap2 methods to manipulate it.

Here’s an example that changes the map type of the overview and sets up a “click” listener on it.

Restrictions

  • Many GMap2 methods can’t be used on the overview until the GOverviewMapControl has completed its initialisation. If you try to perform them in the same “time slice” as the GOverviewMapControl was created, you’ll get an error. The calls can be deferred, like thissetTimeout("ovmap.setMapType(G_SATELLITE_MAP);",1);.
  • There’s no point using setCenter() or setZoom() on the overview, since the GOverviewMapControl code will update those settings the next time the main map information changes.

Heart problems in babies

Heart Disease

One baby in 100 is born with heart or circulation problems. With improvements in ultrasound scan techniques, most can now be detected while the baby is still in the womb

Causes of heart problems

It’s thought that most heart problems in babies are due to faulty genes. From conception, when sperm and egg combine, a complex construction process occurs to create a human embryo. We all carry a small number of faulty genes and if there’s a fault in the gene signalling, a structural heart problem may appear.

In small communities, where relatives are more likely to marry, there is less variation in the genes and it is more likely that both parents will carry the same rare genetic faults. This situation is known as a small gene pool, and it’s dangerous because genetic conditions such as heart abnormalities are more likely to occur. In larger communities, where there’s more mixing of different genes, genetic problems are less common.

A proportion of babies with heart malformations have problems with the chromosomes, which can be detected by tests during pregnancy, providing an early clue that the child may be at particular risk. For example, many pregnant women are screened for Down’s syndrome (where there are three rather than two copies of chromosome number 21), in which up to 40 per cent of babies are born with a heart problem.

There are other causes of congenital heart disease too. For example, mothers with diabetes have a two per cent chance of having a baby with a heart problem.

However, most of the babies born with heart problems don’t come from high-risk groups. The reason is simply that this is a comparatively rare, almost unpredictable condition – and there are only small numbers of high-risk people in the population.

Diagnosing heart problems

The majority of heart problems in babies are detected at a routine ultrasound scan, usually at 18 to 20 weeks, although some aren’t discovered until after the birth. If you have worries, talk to your GP or obstetrician. If they suspect problems, they may refer you to a specialist unit for further tests.

At about 19 weeks gestation, a baby’s heart is less than 1cm across and weighs only 1g or so (compared with 500g for an average adult heart). It also beats more than twice as fast as an adult’s.

The circulation of a foetus is different from that of a newborn baby, being connected to a placenta and having three extra channels that must close or reverse at birth.

Good-quality ultrasound equipment is essential to look at the tiny, fast-moving cardiac structures. Even so, ultrasound images appear grainy – it requires practice and an experienced eye to identify problems.

Advances such as the colour flow doppler detect the movement of red blood cells, highlighting areas of abnormal blood flow that may indicate circulation problems. These may have been missed by a conventional scan.

Cardiomyopathy

Heart Disease

What is cardiomyopathy?

Cardiomyopathy is a disease that changes the structure of the muscle tissue in the heart, or makes it weaker, so it’s less able to pump blood efficiently.

Symptoms may appear suddenly with loss of consciousness, or there may be warning signs such as pain in the chest (angina), unexplained breathlessness or a rapid heartbeat (palpitations or arrhythmia).

Cardiomyopathy may be either:

  • Primary – no specific cause can be identified
  • Secondary – causes can be identified, such as hypertension (high blood pressure), heart valve disease, artery diseases or congenital heart defects, as well as disease affecting organs other than the heart. Alcohol and drug use (both street drugs and medical drugs) can also cause cardiomyopathies

There are three main types of cardiomyopathy or disease of the heart muscle:

  • Hypertrophic cardiomyopathy – the most common cause of sudden and unexpected death in people under 30
  • Dilated cardiomyopathy – the most common type of cardiomyopathy
  • Restrictive cardiomyopathy – the least common type, usually seen in the elderly
  • Symptoms of cardiomyopathy

    The symptoms may depend on the type of cardiomyopathy. It may present at any age, causing:

    • Breathlessness on exercise
    • Chest pain
    • Palpitations
    • Dizziness
    • Collapse with loss of consciousness
    • Tiredness and general lack of energy
    • Blood clot formation with pulmonary emboli or stroke
    • In the most severe cases, sudden death

Heart attack recovery

Heart Disease

Risks after a heart attack

Many people live in fear of another heart attack – and with good reason. About 10 per cent of those who have a heart attack will have another one within a year of leaving hospital. This risk drops to about three per cent every year after that.

Proper rehabilitation, which includes making changes to your lifestyle, can reduce these risks and increase your life expectancy. If you’re not offered a formal rehabilitation programme, ask your doctor if there’s one in your local area.

Clinical Trials

Heart Disease

The National Heart, Lung, and Blood Institute (NHLBI) is strongly committed to supporting research aimed at preventing and treating heart, lung, and blood diseases and conditions and sleep disorders.

NHLBI-supported research has led to many advances in medical knowledge and care. For example, this research has helped explore methods and devices for treating heart problems.

The NHLBI continues to support research on various heart treatments, including pacemakers. For example, a current study is exploring the benefits of temporary biventricular pacemakers for patients who have had cardiopulmonary bypass surgery.

Much of the NHLBI’s research depends on the willingness of volunteers to take part in clinical trials. Clinical trials test new ways to prevent, diagnose, or treat various diseases and conditions.

For example, new treatments for a disease or condition (such as medicines, medical devices, surgeries, or procedures) are tested in volunteers who have the illness. Testing shows whether a treatment is safe and effective in humans before it is made available for widespread use.

By taking part in a clinical trial, you might gain access to new treatments before they’re widely available. You also will have the support of a team of health care providers, who will likely monitor your health closely. Even if you don’t directly benefit from the results of a clinical trial, the information gathered can help others and add to scientific knowledge.

If you volunteer for a clinical trial, the research will be explained to you in detail. You’ll learn about treatments and tests you may receive, and the benefits and risks they may pose. You’ll also be given a chance to ask questions about the research. This process is called informed consent.

If you agree to take part in the trial, you’ll be asked to sign an informed consent form. This form is not a contract. You have the right to withdraw from a study at any time, for any reason. Also, you have the right to learn about new risks or findings that emerge during the trial.

For more information about clinical trials related to pacemakers, talk with your doctor. You also can visit the following Web sites to learn more about clinical research and to search for clinical trials:

http://clinicalresearch.nih.gov
http://www.clinicaltrials.gov
http://www.nhlbi.nih.gov/studies/index.htm
http://www.researchmatch.org
For more information about clinical trials for children, visit the NHLBI’s Children and Clinical Studies Web page.

History

Heart Disease
The first implantable pacemaker

The first implantable pacemaker

n 1899, J A McWilliam reported in the British Medical Journal of his experiments in which application of an electrical impulse to the human heart in asystole caused a ventricular contraction and that a heart rhythm of 60-70 beats per minute could be evoked by impulses applied at spacings equal to 60-70/minute.
In 1926, Dr Mark C Lidwell of the Royal Prince Alfred Hospital of Sydney, supported by physicist Edgar H Booth of the University of Sydney, devised a portable apparatus which “plugged into a lighting point” and in which “One pole was applied to a skin pad soaked in strong salt solution” while the other pole “consisted of a needle insulated except at its point, and was plunged into the appropriate cardiac chamber”. “The pacemaker rate was variable from about 80 to 120 pulses per minute, and likewise the voltage variable from 1.5 to 120 volts” In 1928, the apparatus was used to revive a stillborn infant at Crown Street Women’s Hospital, Sydney whose heart continued “to beat on its own accord”, “at the end of 10 minutes” of stimulation.
In 1932, American physiologist Albert Hyman, working independently, described an electro-mechanical instrument of his own, powered by a spring-wound hand-cranked motor. Hyman himself referred to his invention as an “artificial pacemaker”, the term continuing in use to this day.
An apparent hiatus in publication of research conducted between the early 1930s and World War II may be attributed to the public perception of interfering with nature by ‘reviving the dead’. For example, “Hyman did not publish data on the use of his pacemaker in humans because of adverse publicity, both among his fellow physicians, and due to newspaper reporting at the time. Lidwell may have been aware of this and did not proceed with his experiments in humans”.
An external pacemaker was designed and built by the Canadian electrical engineer John Hopps in 1950 based upon observations by cardio-thoracic surgeon Wilfred Gordon Bigelow at Toronto General Hospital . A substantial external device using vacuum tube technology to provide transcutaneous pacing, it was somewhat crude and painful to the patient in use and, being powered from an AC wall socket, carried a potential hazard of electrocution of the patient by inducing ventricular fibrillation.

In 1958, Arne Larsson (1915-2001) became the first to receive an implantable pacemaker. He had a total of 26 devices during his life and campaigned for other patients needing pacemakers.

In 1958, Arne Larsson (1915-2001) became the first to receive an implantable pacemaker. He had a total of 26 devices during his life and campaigned for other patients needing pacemakers.

A number of innovators, including Paul Zoll, made smaller but still bulky transcutaneous pacing devices in the following years using a large rechargeable battery as the power supply.
In 1957, Dr. William L. Weirich published the results of research performed at the University of Minnesota. These studies demonstrated the restoration of heart rate, cardiac output and mean aortic pressures in animal subjects with complete heart block through the use of a myocardial electrode. This effective control of postsurgical heart block proved to be a significant contribution to decreasing mortality of open heart surgery in this time period.
In 1958 Colombian electrical engineer Jorge Reynolds Pombo constructed an external pacemaker, similar to those of Hopps and Zoll, weighing 45 kg and powered by a 12 volt auto battery, but connected to electrodes attached to the heart. This apparatus was successfully used to sustain a 70 year old priest, Gerardo Florez.
The development of the silicon transistor and its first commercial availability in 1956 was the pivotal event which led to rapid development of practical cardiac pacemaking.
In 1958, engineer Earl Bakken of Minneapolis, Minnesota, produced the first wearable external pacemaker for a patient of Dr. C. Walton Lillehei. This transistorised pacemaker, housed in a small plastic box, had controls to permit adjustment of pacing heart rate and output voltage and was connected to electrode leads which passed through the skin of the patient to terminate in electrodes attached to the surface of the myocardium of the heart.
The first clinical implantation into a human of a fully implantable pacemaker was in 1958 at the Karolinska Institute in Solna, Sweden, using a pacemaker designed by Rune Elmqvist and surgeon Åke Senning, connected to electrodes attached to the myocardium of the heart by thoracotomy. The device failed after three hours. A second device was then implanted which lasted for two days. The world’s first implantable pacemaker patient, Arne Larsson, went on to receive 26 different pacemakers during his lifetime. He died in 2001, at the age of 86, outliving the inventor as well as the surgeon.
In 1959, temporary transvenous pacing was first demonstrated by Furman et al. in which the catheter electrode was inserted via the patient’s basilic vein.
In February 1960, an improved version of the Swedish Elmqvist design was implanted in Montevideo, Uruguay in the Casmu Hospital by Doctors Fiandra and Rubio. That device lasted until the patient died of other ailments, 9 months later. The early Swedish-designed devices used rechargeable batteries, which were charged by an induction coil from the outside.
Implantable pacemakers constructed by engineer Wilson Greatbatch entered use in humans from April 1960 following extensive animal testing. The Greatbatch innovation varied from the earlier Swedish devices in using primary cells (mercury battery) as the energy source. The first patient lived for a further 18 months.
The first use of transvenous pacing in conjunction with an implanted pacemaker was by Parsonnet in the USA, Lagergren in Sweden and Jean-Jaques Welti in France in 1962-63. The transvenous, or pervenous, procedure involved incision of a vein into which was inserted the catheter electrode lead under fluoroscopic guidance, until it was lodged within the trabeculae of the right ventricle. This method was to become the method of choice by the mid-1960s.

World's first Lithium-iodide cell powered pacemaker. Cardiac Pacemakers Inc. 1972

World's first Lithium-iodide cell powered pacemaker. Cardiac Pacemakers Inc. 1972

The preceding implantable devices all suffered from the unreliability and short lifetime of the available primary cell technology which was mainly that of the mercury battery.
In the late 1960s, several companies, including ARCO in the USA, developed isotope powered pacemakers, but this development was overtaken by the development in 1971 of the lithium-iodide cell by Wilson Greatbatch. Lithium-iodide or lithium anode cells became the standard for future pacemaker designs.
A further impediment to reliability of the early devices was the diffusion of water vapour from the body fluids through the epoxy resin encapsulation affecting the electronic circuitry. This phenomenon was overcome by encasing the pacemaker generator in an hermetically sealed metal case, initially by Telectronics of Australia in 1969 followed by Cardiac Pacemakers Inc of Minneapolis in 1972. This technology, using titanium as the encasing metal, became the standard by the mid-1970s.
Others who contributed significantly to the technological development of the pacemaker in the pioneering years were Bob Anderson of Medtronic Minneapolis, J.G (Geoffrey) Davies of St George’s Hospital London, Barouh Berkovits and Sheldon Thaler of American Optical, Geoffrey Wickham of Telectronics Australia, Walter Keller of Cordis Corp. of Miami, Hans Thornander who joined previously mentioned Rune Elmquist of Elema-Schonander in Sweden, Janwillem van den Berg of Holland and Anthony Adducci of Cardiac Pacemakers Inc.Guidant.