We have seen hundreds of peacocks dancing with its beautiful feathers wide open. It's not just because it's raining or the peacock is happy; it is actually trying to attract its partner for mating.

There are different kinds of actions, different modes of attraction in each kind of species to attract its partner. One such is PHEROMONES. These are something which you can't see, which you can't feel, which you can't smell. But yes; there presence adds an essence to your life.

These pheromones are actually a special kind of chemical messengers emitted by any species which will evoke responses in another individual of the same species.

The scientists have studied the existence of pheromones extensively in insects, but higher organisms like pigs and elephants may also emit pheromones. It is now known that, human beings also do emit pheromones, though not scientifically proved. In past fifty decades, thousands of insects have been chemically elucidated for the structure, composition, function and the capacity of these magical messengers.

ALARM PHEROMONES: Though there are too many questions unanswered about pheromones, scientists have succeeded in proving their existence in lower organisms like insects. For example, bees use isopentyl acetate as an alarm signal. The "Guard Bees" will raise their abdomen and emit the pheromones and these pheromones are transmitted by beating their wings faster and continuous.

This will make the entire bee hive aware of the incoming threat. When a bee stings a target, these pheromones are deposited on the spot along with the venom which encourages the other bees to attack the target, stinging at the same place. Since the pheromones used here are for alarming signals, they are generally called "alarm pheromones".

TRAIL PHEROMONES: Ants extensively use pheromones. When ants return to their nest with the food, they lay down a trail pheromone. This trail attracts and guides other ants to the food. By chance, if the train is cut off in between, by a chalk or some powder etc., the ants will get totally confused. They start wandering randomly or they return in the opposite direction.

QUEEN MANDIBULAR PHEROMONES: have you ever seen any "Queen Bee" working?! No. She never does. Honey bee queens always literally are surrounded by a retinue of worker bees. This is mainly because of the pheromones emitted by the queen bees from their mandibular glands. These pheromones are actually mixture of alcohols and organic acids. These pheromones will

- Induce the worker bees to feed and groom the queen bee

- Inhibit the worker bees from building queen cells and rearing new queens

- Inhibit ovary development in the worker bees.
Other than this, the pheromones are also found in many other insects like silkworm moths (from which they were first isolated), different species of spiders, millipedes, the turnip moths, gypsy moths, Japanese beetles and a variety of parasitic and symbiotic beetles.

The complex but primitive single celled amoeba Dictyostelium also uses a pheromone to attract others of its kind and follow reproduction.



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The Universe... The incredible difference in scale between the tiny world we live in every day and the vastness of all time and space begs the question of whether we will ever be able to grasp the fullness of the cosmos. But that doesn't stop us from trying. In fact, contemplating the great unknowns must be one of the oldest hobbies in human experience.

5. Rare Antimatter

Matter and antimatter are, in theory, created at the same time by the same event. When a normal baryonic particle is created, an antiparticle of the same mass and opposite charge is also created. However, while we have created antimatter in laboratories on Earth, we don't see it in the universe around us. No one seems to know what happened to all the antimatter that should be there...

4. Time

You think you know what time is? Okay, try defining it without using any terms that rely on time. Time is... well, it's time. It's what keeps every event from happening simultaneously, and it's what distinguishes something that happened in the past from something that will happen in the future. Is it a dimension, like space? Is it a quality of matter? Is it merely an illusion, possibly created to boost sales of digital watches? The smartest guys in the world get headaches from this one.

3. The Beginning of the Universe

How did the universe begin? Did the universe ever begin? If the universe includes everything that we know, including time, could there possibly even be a "before" before the beginning of the universe. Current theories generally talk about a "Big Bang," which is a massive expansion of all matter and energy from a single point, which is still continuing through the present day. What started the bang? Where did all the energy and matter come from? Are these questions even meaningful? What about creationism, if that is for you? If God created the universe and all the physical laws in it, what is he doing now that it is running itself?

2. Multiple Universes

Current quantum physics raises the possibility that there are many universes besides our own, existing in the same space and time, but only interacting in certain limited ways. These universes may have their own separate histories and futures, and even their own laws of physics. This is all vague theory for the moment, but some day it may be possible to travel to the universe where your favorite singer won American Idol or visit with evil Spock.

1. Grand Unification Theory

For decades, physicists have been trying to make sense of the difference between Isaac Newton's classical physics (you know, what you use to play pool) Einstein's relativistic physics, that involve very large or massive things at enormous velocities, and Heisenberg's (and others') quantum physics, which concerns things so small that you can't even measure them without changing the result. These three sets of physical laws seem to play by their own rules, largely ignoring each other, and yet they all relate to the same universe. And so physicists have hunted for the Grand Unification Theory, which would substitute for all of these incomplete sets of laws and make sense of it all. Perhaps it doesn't exist. Or perhaps it's just too complex for human minds to grasp. One way or the other, it's going to keep scientists arguing for some time to come.



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Genetics is a notorious course for demanding a high-volume of information in a short amount of time. However, there are studying methods to assist students in learning efficiently and effectively. I have studied and interviewed groups of medical and science students that have mastered their course work. It is true that there are specific and detailed guidelines that these students adhere to and credit for their academic success. The successful student must understand the fundamental science of DNA and expand on it as a discipline of inheritance and variation in organisms. With some time and applying these study strategies and tips from past honor students of Genetics, you will greatly improve your academic performance.

Study Skill #1 -The basics are essential. Genetics is a course that builds on itself. All the complex principles, genetic disorders, and population calculations relate back to the fundamental laws of cellular mechanisms. This means you absolutely have to know mitosis and meiosis before you can understand the process of non-disjunction. It would be helpful to review the processes of DNA replication, transcription, and translation.

Study Skill #2 - Write out pedigrees for every mode of inheritance. Buy a small dry erase board and do this repeatedly, until you can do it from memory. More importantly, you must understand why disorders will show up and keep in mind the percentages of the offspring affected. These questions are not difficult once you do them over and over again, and they should not be missed on an exam; all the necessary information is included in the pedigree.

Study Skill #3 - Practice for Population questions. Similar to pedigrees, these questions already contain the information you need to solve it. Understand the concept first, but practice finding the numbers and working them out as often as you can.

Study Skill #4 - Make charts for the disorders. Often there is not a clear relationship between the faulty genetic process and presenting clinical symptoms. List the disorders in the rows and make columns for the genotype, phenotype, symptoms, prognosis, and the genetic mechanism.



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You've seen the snowmakers on the side of the hill at your local ski hill and wondered to yourself, "How do those work?" As far as you can tell it looks like a giant sprinkler, spraying water high above the slopes so it freezes and turns into snow. But could it really be as simple as spraying a light mist of water into the air? The answer is yes...and no.

You see, water is a funny little liquid. A natural water droplet that forms after being pushed through the nozzle of a spray bottle, sprinkler, or pressure washer may not freeze, even if it is cooled well below freezing. Known as "supercooled" water, these droplets just can't seem to form themselves into a frozen crystal because in order for these natural droplets to freeze, they needs something to freeze onto. That's right, without something to attach themselves to, water droplets can remain liquid even if it is well below freezing! That's why some places in the world get freezing rain. This form of precipitation is simply supercooled water, the second it hits the ground though (or a tree, car, house, etc) it freezes, creating an amazing but dangerous layer of ice wherever the storm passes.

So how the heck do you get water to turn into snow then? The most common way is to break down the water into even tinier, unnatural particles using compressed air. By running compressed air through the nozzles along with the air, the water is "atomized", or broken down into tiny droplets. These unnatural droplets actually will freeze in cold air. Plus, expanding air looses heat, so this system also cools these droplets, further helping the freezing process.

However, making each droplet "freezable" using compressed air isn't always the most efficient thing to do. Most snowmakers will use two types of nozzles on each machine. Remember that natural water won't freeze unless it has something to freeze onto? Well, the first type of nozzle runs water and compressed air, making snow crystals. The other type of nozzle sprays only a fine mist of water. However, the nozzles are positioned so that the mist from the water-only nozzles will mix with the snow crystals from the air-water nozzles. The plain water freezes onto the snow crystals multiplying snow output without requiring extra compressed air. When you see large, barrel shaped snowmakers, frequently they will have one ring of air-water nozzles and many rings of water-only nozzles.

Snowmaking technology is now making a movement from the ski hill to the backyard. The same technology applies, but instead of high pressure water pumps, home snowmakers use a pressure washer, like what you use to wash your car with. Usually, these snowmakers use a vertical setup where the air-water nozzle is on the bottom, with as many as four water-only nozzles are positioned above. Small shop air compressors are used to supply the compressed air side of the recipe making home snowmaking incredibly easy and affordable.



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The Stem cells are predominantly called the "master cells" of the human body because of their ability to create all other tissues, organs, and systems in the body. The stem cells are the building blocks of your blood and immune system. They are the factory of the blood system and continually make new copies of themselves and produce cells that make every other type of blood --Red blood Cells, White Blood Cells and Platelets. There are basically three sources where stem cells can be easily found.

1) Bone Marrow
2) Peripheral Blood and
3) Umbilical Cord Blood

Various researches done in this field suggest that stem cells obtained from cord blood are relatively more advantages over those retrieved from bone marrow or peripheral blood because they are immunologic ally "younger" and appear to be more versatile. They also demonstrate an important characteristic with embryonic stem cells and are able to differentiate into nearly all cell types in the body. Secondly it is easy to get stem cells from cord blood because they are readily obtained from the placenta at the time of delivery. Harvesting stem cells from bone marrow requires a surgical procedure, performed under general anesthesia and can cause post-operative pain or pose a small risk to the donor.

The promise of using stem cells for medical treatments have been the focus of researches various projects that are showing encouraging results.

• Cord blood stem cells help in the treatment of diseases such as Alzheimer's and Parkinson's.

• They have also proven their ability in the treatments for heart disease, allowing patients to essentially "grow their own bypass."

• Stem cells have the potential to help cure many life-threatening ailments like leukemia, non-Hodgkin's lymphoma, anemia, inherited disorders and all other deficiencies of the immune system.

• Lifestyle diseases such as diabetes, liver disorders and heart ailments can also be treated with stem cells.

On the other hand a wider range of recipients can benefit from cord blood stem cells. These can be stored and transplanted back into the donor, to a family member or to an unrelated recipient. For a bone marrow transplantation, there must be a nearly perfect match of certain tissue proteins between the donor and the recipient. When stem cells from cord blood are used, the donor cells appear more likely to "take" or engraft, even when there are partial tissue mismatches.

Certain complications like graft versus host disease (GVHD), in which donor cells can attack the recipient's tissues, are less likely to occur with cord blood than with bone marrow. This may be because cord blood has a muted immune system and certain cells, usually active in an immune reaction, are not yet educated to attack the recipient. A research done in this field revealed that children who received a cord blood transplant from a closely matched sibling were 59 percent less likely to develop GVHD than children who received a bone marrow transplant from a closely matched sibling.

Cord blood also is less likely to contain certain infectious agents, like some viruses, that can pose a risk to transplant recipients .In addition, cord blood may have a greater ability to generate new blood cells than bone marrow. Ounce for ounce, there are nearly 10 times as many blood-producing cells in cord blood. This fact suggests that a smaller number of cord blood cells are needed for a successful transplantation.

With the rapid advancement in Medical Science there has also been a corresponding development in the number of preserved cord blood units being used in regenerative medicine applications. If expectant parents store their baby's cord blood in a family bank, the stem cells are immediately available for use in medical treatments, including future therapies to repair or replace damaged heart tissues. As a result, an infant's cord blood could prove to be a life-saving treatment option if that child is born with a congenital heart defect, or later in life following a sudden and serious heart attack. In regenerative medicine, the latest scientific evidence suggests that using one's own stem cells likely delivers more favorable outcomes.



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As science teachers prepare to go back to school for the next school year, some have already returned, they are always searching for good online resources to supplement their lessons. It is always nice when someone helps them by previewing science websites and make recommendations.

The best science education websites are interactive, allowing students to make changes to or manipulate variables to observe what happens and share with others. This falls within the boundaries of inquiry-based teaching and learning. Students are developing their own experiments, observing the results, and reporting their findings.

The following websites have been previewed and meet the criteria of interactive and inquiry-based:

FOSS Web - is designed to support Full Option Science System (FOSS) Science K-8 science kits, but anyone can use the interactive activities for grades K - 8.

Volcano Cams - provides real-time views of volcanoes around the world. Students can observe volcanoes and develop their own experiments using these virtual cams for grades 5 - 12.

Explore eLearning - provides simulators for all science concept areas for grades 3 - 12.

Real-time Stream Flow Data across the Nation - by the US Geological Survey (USGS) provides real-time data typically are recorded at 15- to 60-minte intervals and transmitted to the U.S. Geological Survey offices every four hours. Data can be selected by state and county for grades 8 - 12.

Real-time Water Quality Data across the Nation-by the US Geological Survey (USGS) provides real-time water quality data are returned directly field instruments. Data are updated at five minute to one-hour intervals. Data can be selected by state and county for grades 8 -12.

Design a Roller Coaster - allows students to design their own roller coaster. They are building a conceptual coaster using the same physics concepts that are used to design real coasters for grades 6 - 12.

Human Anatomy Online - allows students to explore the Human Anatomy. Each topic has animations, 100's of graphics, and thousands of descriptive links, for grades 4 - 12.

Earth and Atmospheric Kids Crossing - allows students explore water, atmosphere, and weather for grades 3 - 8.

Recycle City - lets students explore plenty of ways to see how a city's residents recycle, reduce, and reuse waste for grades 3 - 8.

MBG Net - allows students to explore Biomes, Freshwater Systems, and Marine Systems of the World for grades 6 - 12.



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It is said that in future almost all the vehicles will operate on fuel cells alone or with hybrid systems using both batteries and fuel cells in which the battery supplies power for acceleration and speed. Now all the major automotive manufacturers are on the process of developing fuel cells as the replacement for the conventional automobile engine to provide advantage of high efficiency of fuel cells.

A team of scientists used microfabrication technology in order to produce low-cost, high-volume production of fuel cells rather than building them by hand. The goal is to fabricate fuel cells in a manner similar to the way that many types of integrated circuits are presently manufactured. Scientists are on the verge of developing an advanced version of the fuel cell, which would use methanol as a fuel to provide far greater energy storage capability. In future, the new miniature fuel cell could be used in everything from automobiles to cell phones and computers.

The polymer exchange membrane fuel cell (PEMFC) is one of the futuristic fuel cell technologies. This type of fuel cell will probably power up cars, buses and maybe even our houses. The PEMFC uses one of the simplest reactions of any fuel cell. Scientists are in their effort to boost fuel efficiency by taking different approaches to the cell design. One of the successful approaches is to combine fuel cell and battery powered vehicles. Even Ford Motors and Airstream are developing this concept vehicle powered by a hybrid cell named Hyseries Drive. Meanwhile, Ford claims that vehicles have a fuel economy comparable to 41 miles per gallon .These vehicles use a lithium battery to power the cars, as the fuel cell recharges the battery.

United Technology corp. was the first company to manufacture the fuel cell for use as a co-generation power plant in hospitals, universities and large office buildings. Fuel cell applications are now used in many things such as Base load Power plants, Electric and hybrid vehicles, auxiliary power, off grid power supply, note book computers, portable charging docks and smart phones.



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Ethanol is a viable, homegrown energy alternative to fossil fuel and is available today in E10 (10 percent ethanol/90 percent gasoline) and E85 (85 percent ethanol/15 percent gasoline) blends. Used as a clean-burning fuel additive, ethanol is a renewable fuel made from plants, usually from sugar cane and maize. There are five parts to the ethanol process; Conversion, fermentation, distillation, filtration and dehydration.

The University of Florida has been involved in biomass-to-energy research for about 20 years. New research at UF by Dr. Lonnie Ingram on variety of plant waste products proves that they are suitable for "cellulosic" ethanol production. The same kind of ethanol produced from this experiment too; but the source and process are different, allowing more efficient use of organic wastes for fuel production. It is proved that Ethanol blends are higher in octane than regular gas, about 100 compared to 87. Though we can see the difference in the reduction in fuel economy and less mileage per gallon, but the engine stays cooler, runs cleaner and produces less pollution.

Recent studies proved that it reduces the global warming due to its clean burning and cuts the greenhouse gas emissions by 18 percent to 29 percent a gallon. It powers flux fuel vehicles. Ford, General Motors and DaimlerChrysler have announced to producing 50 percent of their new vehicles as flex-fuel vehicles powered by E85 ethanol by 2010. Indy 500 utilized 100 percent ethanol in the tanks of 33 cars used in 2007 race and the drivers said that the use of ethanol improved the mileage by 30 percent.

The software genius Bill gates invested in Pacific Ethanol to help fund the construction of an ethanol plant in Madera County, California. Virgin Atlantic Airways' Richard Branson has also invested in cellulosic ethanol plants to make fuel which is from the waste product of the plant and measured to be the next energy step after corn ethanol. DuPont plans to open its first pilot plant to manufacture cellulosic ethanol in 2008.



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One of the best methods of purifying water is the distillation process. It all begins with a heat source that vaporizes water causing it to become steam. As the steam cools and condenses back into water the contaminants are separate out due to boiling point differences. The result? Crystal clear, perfect water.

Don't be fooled into thinking that your drinking water is pure just because it comes from a well, spring, glacier, or other location that is considered to be pure. That's not the case. All naturally-occurring water has things in it we don't need to be drinking.

The distillation process takes untreated water (also referred to as raw) and heats it to the boiling point where it starts to vaporize. The trick to getting 100 percent pure water is to maintain the water at a constant temperature and keep the vaporization process going. It's at this constant temperature that the separation of contaminants takes place; while the water is vaporizing, the other elements you don't want in your water are NOT vaporizing, due to differences in their boiling points.

The removal of the elements you don't want in your water is made possible because the harmful minerals and compounds in water either have a lower boiling point than water itself, or a higher boiling point. Taking advantage of these differences is what enables us to distill--to separate-- water from these undesirable compounds. The separation process also applies to disease organisms. Although so small you can't see them, they are eliminated out of the boiling water so they can't pollute your end product - the purified drinking water.

When the water is vaporized in the distillation process, the steam is funneled into a condenser where the water converts back to its liquid form. As it collects, the fluid gathers in a container. The remainder that didn't vaporize is referred to as sediment, and it stays in the original container that held the water prior to its vaporization. To be certain of clean water one can re-run the water back through the unit to ensure all other foreign elements have been removed.

Depending on the kind of water distillation system you have, you may not need to repeat the process. In an interesting note, the units used to distill many liquors (such as gin, brandy, and whiskey) are similar to the units commonly used to distill water.

Currently the conventional method to heat the water is electricity or gas, but that hasn't stopped evergreen proponents from proposing solar power. While a viable alternative, it would take a great deal longer to vaporize water and only in smaller quantities.



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