What Is A Wavefront Lasik Procedure Like?

Let’s walk through what a client experiences when attending a Lasik center for a Wavefront Lasik procedure. The procedure itself generally only takes between five and ten minutes for each eye in total, and both eyes are done during the same procedure. The actual time to reshape the eye with the Lasik excimer laser is usually less than 15 seconds per eye.

Any person’s vision problems are generated by small “aberrations” within the eye that prevents the light from focusing objects as they should. The Lasik equipment locates and classifies these aberrations and then processes them so that the Lasik physician will correct these and allow the light to focus properly once the eye has healed.

In a Wavefront Lasik procedure, the patient stares at one point while a light is sent into the eye, which is reflected back and read by a Lasik Wavefront sensor. The distortions in this reflected light are mapped using a small computer within the Lasik system, and then this information is used to guide the laser that treats the eye.
Once the light creates the map for the eye, the Lasik surgeon has to create a small flap to access the cornea. This is done using a laser (this type of Lasik procedure is known as IntraLasik, or bladeless Lasik) or a small blade known as a microkeratome.

This flap is then opened to allow the cornea to be reshaped by the Lasik excimer laser actually reshapes the cornea, which is the crucial part of the Lasik procedure. In order to determine exactly how to reshape it, the map created earlier by the Wavefront sensor is used to direct the beam of light accurately. The Lasik physician uses these precise tools to get the clearest vision results possible.

This custom Lasik procedure can not only correct such standard problems as nearsightedness, but can also address aberrations that create light halos, glare, haze, or starburst patterns. Once the Lasik physician determines that all relevant aberrations have been eliminated, he replaces the flap in its proper position, where it adheres normally and will heal naturally.

As mentioned earlier, this entire Lasik process takes between ten and fifteen minutes per eye. A patient gets a mild sedative and eye numbing drops to make the procedure both relaxing and painless. Most people notice an improvement in vision due to Lasik almost immediately.

Once the Lasik procedure is finished, you will get some eye drop medication to lubricate and protect your eyes. This medication (and the liquid in the drops themselves) may cause some blurring, and so for this reason (and to avoid any eyestrain) you should arrange for someone else to drive you home. It is also a good idea to go to sleep as soon as possible after the Lasik operation in order to promote even faster healing.

To promote optimal healing the Lasik physician often gives a plastic shield to wear over your eyes for the first night or two. Follow closely any recommendations by the Lasik physician. Do further investigation into this great new Lasik procedure, and get a clearer focus on your future!

Hazards Of Cyanide In Mining

The use of cyanide in the mining process of metals such as gold and silver, leads to severe environmental risks. The use of cyanide in gold mining has led to environmental disasters in many countries across the world such as the United States, Canada, China, Guyana, Bolivia, Zimbabwe, Philippines and Ghana. Recently, Community groups and NGOs in Europe and the United States issued a report which exposed the danger of unregulated cyanide compound releases from mines around the world.

Cyanide is deadly for human beings as well as the environment. The main risks associated with the use of cyanide in mining process are exposure of workers to concentrated hydrogen cyanide gas, leaking of cyanide into the environment and exposure of surrounding communities to cyanide due to accidental releases. During the mining process, the release of cyanide along with other toxic chemicals such as arsenic, lead, cadmium and mercury, leads to harmful effects and permanent damage to some species of animals, plants and human beings. It may also result in deforestation, soil erosion, land slides, and contamination of underground water.

The release of arsenic and other poisonous chemicals during the cyanide leaching process is very dangerous. The cyanide-leach wastes of mining process have the potential to negatively impact municipal sewage and water treatment procedures. It also potentially increases the human intake of several toxic substances. All the cyanide-containing water bodies formed during gold mining milling operations are hazardous to wild animals and migratory birds such waterfowl and bats, if not managed properly. Even accidental leaking of cyanide solutions into rivers and streams will kill fish and other aquatic animals massively. Especially, freshwater fish are the most cyanide-sensitive aquatic organisms.

Workers at gold mining operations can be exposed to cyanide during the heap leaching or tank extraction process. Cyanide is very harmful to human being as it acts as a poison to the human body. Severe breathing difficulties develop when cyanide is inhaled, swallowed or absorbed through the skin. Cyanide blocks the absorption of oxygen by cells, making the victim to suffocate. Exposure to concentrated levels of cyanide can be fatal to the human beings. Exposure to very low concentration of cyanide may cause cancer in people or animals.

We are not certain about the presence and concentration of numerous cyanide compounds in mining wastes. We are also not sure about the presence, persistence, and toxicity of cyanide and related compounds in the environment. But as the effects of cyanide are getting more obvious, the opposition to cyanide leaching in gold mining is also increasing.

The use of cyanide in mining causes an unreasonable risk to the health of people, wildlife, and fish. As the hazards of cyanide in mining process are very much obvious, it is the responsibility of the Government and mining companies to take essential steps. The International Cyanide Management Code provides direction and guidance on how to manage cyanide to ensure protection of workers, the environment and the communities adjacent to mining operations. Mining waste should be regulated in the same manner as other chemical or industrial waste. The public needs enough awareness about mining hazards. The government should ban mining projects that result in environmental hazards in order to prevent ecological disasters. Citizens must also oppose such mining projects. Many organizations in countries such as United States, Canada and Turkey have started associations for banning cyanide leaching in mining.

Supplies for Cole-Parmer Laboratory Equipment

Laboratories in schools, colleges, pharmaceutical companies, hospitals, perfume manufacturers, and other industries all require different types of laboratory glassware for their day to day functions. All these institutions require these products in good quality as precision is a crucial factor in the success of experiments and manufacturing processes.

Glassware products are always predisposed to breakage on heating but since heating forms a major part of nearly all experiments we need glass equipment that can withstand heat and still maintain accurate measurements. One company that has been able to provide high quality lab glassware is Cole Parmer. The products from this company include lab and industrial glass equipment and these feature bottles, burettes, centrifuges, containers, cylinders, evaporators, flasks, funnels, pipettes, and stirrers, to mention but a few. This company has also ensured that all its products attain high levels of quality in order to enable all research facilities to function with exceptional efficiency. They also ensure that these supplies are trouble free, safe and convenient, and that they give accurate and steady analytical results. These glassware products also attain and exceed the international quality and safety criteria.

The laboratory glassware products from Cole Parmer are available from different suppliers all around but instead of running around different outlets the internet can provide online sources with best prices and discounts. These online stores also provide information on the features, specifications and costs. These stores also provide safe and prompt shipping of the purchased products. Other than just providing quality products, these products also carry extended warranties to ensure full customer satisfaction.

One of the most renowned online outlets for Cole Parmer glass laboratory ware is . Since 1989 this firm has been supplying customers with quality products at competitive prices while offering exceptional services based on honest customer-buyer relationships. Mass supply makes sales of over $ 1 million annually by selling these products to the government, medium and small as well as fortune 500 companies. They are also authorized resellers for other companies such as Fisher, Sigma-Aldrich, Lab Safety Supply and VWR to mention but a few.

Mass supply makes it easier for people to buy laboratory goods by allowing the purchase of products from different vendors using a single purchase order (PO). In other firms you may require to make different POs for each vendor and at times the cost of creating a single PO can be as high as $150. This allows customers to save time and money, this especially with reference to purchase agents. Scientists and researchers usually do not have time to follow up their orders and issues such as breakages, returns, and back orders, hence Mass Supply’ has a personalised and value added service that ensures the prompt dispatch and safe delivery of its goods.

Science Fair Project Ideas – Part 2

This article is a sequel to Science Fair Project Ideas ? Part 1 but can be read and used independently. Both articles are designed to provide project ideas. The hardest part of a science fair project may very likely be getting started. Once you have an idea in mind it is easy to formulate what experiments and research you will need to do. Until you chose a topic you do not have anything to aim toward. The science fair project is typically designed as an educational tool. This article is not designed to hand you an idea for a project. My goal is that these ideas will point you in the right direction or even give inspiration for another related idea. The three descriptions here will give you an outline, not a project; it is your job to expand on a project idea.

Idea number one: The effect of earthquakes on building structures. The main focus of this idea is to show how lateral ground movement affects the structure of a building. Some answers will only be found through research, specifically on ?inertia?. The experiment suggested here will require a large piece of rough sand paper and at least one Slinky toy (two are needed for a second idea). The set up for this experiment is simple. Place the Slinky on the sandpaper (rough side up). Then pull on the sandpaper to move it about six inches. You should observe that the top half of the Slinky leans backward then catches back up to bottom half once the sand paper stops moving. While an actual building is much more solid than a Slinky, the walls will still bend, since the force of an earthquake is much greater than that of pulling on the sand paper. This experiment can be taken to a second phase. Pull on the sandpaper just as before but in a back and forth motion. Notice how the top of the Slinky reacts to the change in direction. Another variation for this idea is to connect two Slinky toys together and repeat the experiment. The taller Slinky combo will replicate a taller building and you can observe if the height of a building has an effect on the impact of the lateral movement.

Idea number two: How is static electricity is produced. The main focus of this idea is to see how static electricity effects various objects. Some research key words will be ?static charge?, ?protons? and ?electrons?. Your study here will involve the placement, or displacement of electrons. The basic experiment of this idea will require a balloon, string, tape and a hair dryer. Blow up a balloon, tie a string around the bottom (the knot) and tape the other end of the string to a ledge like a table or shelf so that the balloon can hang freely. After washing your hands, rub one rapidly in a back and forth motion across one side of the balloon. Now, allow the balloon to hand freely again. Move your hand close to the balloon without touching it. The balloon should move toward your hand. A great variation for this experiment requires you to add two elements. Mark and ?x? on the balloon where you will rub. Then, get the balloon to spin slowly before placing your hand up to it. This will show that the excess charge is in the location you rubbed. Another fun trick is to turn a faucet on so a very small stream of water is flowing. Comb your hair with a standard comb then hold it up to the stream of water. The water will actually bend away from the comb.

Idea number three: How does a first class lever work? The main focus of this idea is to build a first-class lever and to examine its advantage. Some key terms for this idea that you will need to research are ?fulcrum?, ?effort force?, ?effort arm? and ?load arm?. In this experiment you will need to build a simple lever. Use a broom, table and a chair it you like. Place the broom handle under the edge of the table and across the back of the chair. You should be able to easily lift the table by pushing down on the brush end of the broom if you have your fulcrum (the chair) in the right spot. You can change the experiment by placing the fulcrum under the broom in different spots. Try placing the chair close the table, then close to the brush end of the broom, then in the middle. Compare the amount of effort needed in each location. Another experiment idea is the classic teeter-totter (see-saw). Using two volunteers of different weight, place one on each end of the teeter-totter then experiment by changing placement of the volunteers. What locations work best? How does moving the lighter person toward the center of the teeter-totter affect the lifting abilities? How about moving the heavier person?

These three additional science fair project ideas may give you a good place to start on your project. Please be sure to research each idea extensively and even create your own variations of the experiments. It is likely that more ideas will be presented in future articles.

Ordering Valuable Texts Like Brock Biology of Microorganisms 13th Edition Online

If you are a college student then you must have faced a lot of troubles affording all the books and the needed papers. This is why you must be looking for the best discount rates to get books that you need such as Microbiology an Introduction 11th Edition and Brock Biology of Microorganisms 13th Edition.

You don’t need to worry, because incredible deals and discounts on important books that you might be looking for such as Brock Biology of Microorganisms 13th Edition and Microbiology an Introduction 11th Edition does exist in reality. The best way to find them is by carrying out a small research online for these online discounts. The mistake that most college students do is they buy the books from the first vendor or provider they chance upon; they don’t compare options from more than one provider because they don’t look for more in the first place. This is a huge mistake because many online text book sellers have better prices than others and it is not always the first provider that offers the best prices. So if you are looking to find Microbiology an Introduction 11th Edition or Brock Biology of Microorganisms 13th Edition then make sure to check more than one place for these textbooks to get the best price.

There are many things that you should look for in an online vendor before you make your purchase.

The first thing is of course to make sure that this online vendor is offering the best prices for the textbooks you need.

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The last thing is the rate of delivery; this is due to the fact that many online vendors for textbooks don’t stock the books that they have on offer.

So if you make a purchase for Brock Biology of Microorganisms 13th Edition or Microbiology an Introduction 11th Edition you might not get it delivered for a week or so. This may not help if you want these books soon.

Last but not least, you have to make sure that the online vendor you are using to purchase your textbook is trustworthy. You can find out about that by checking up on the reviews and testimonials of the past buyers and reviewers. You have to make sure that they do deliver and also you have to make sure that they provide safety and security to the users. Because in order to make any purchases, you will have to enter banking details, so you have to make sure that this information is safe. So if you are looking to buy Brock Biology of Microorganisms 13th Edition or Microbiology an Introduction 11th Edition, it is recommended to do shopping online.

Poll Shows Interest In Genetics

A new Harris telephone poll, conducted between April 6 and 9 for the nonprofit Center for Social and Legal Research in Hackensack, New Jersey, shows that the public is optimistic about the benefits but concerned about potential abuses of genetic testing and use of human DNA. Among 1000 adults nationwide, 56% said state DNA databases containing “genetic fingerprints” of all newborns would be “very” or “somewhat” acceptable, and 68% would be likely to ask doctors for genetic tests if they were available at a reasonable price. However, the overwhelming majority (86%) would be concerned if employers and insurers used genetic tests before deciding whether to hire or insure someone. Some 85% agreed that a national bioethics advisory commission should be established to advise and make recommendations on bioethical issues arising from human biology research.

Center president Alan Westin (Columbia University) said of the poll, “At a time of downsizing government and hostility to spending tax dollars, it is quite striking that more than 8 in 10 members of the public believe it would be valuable to have a government commission look into the uses of genetic testing and recommend protective policies.”