Science blog

Producing silk isn't as easy as it sounds. We're going to examine some of what's involved including a look at what typical mass production is in some of the more productive countries such as Japan, China and Thailand. Silk production is done in stages. The first stage is hatching the silkworm egg in a controlled environment. This is usually done in an aluminium box. The boxes first have to be examined to make sure they are free of disease. The female silkworm usually lays about 300 to 400 eggs at a time. In an area about the size of a piece of typing paper about 50 moths can lay over 20,000 eggs at one time. Each of these eggs is about the size of a pinhead and virtually undetectable to the human eye. After laying the eggs the female dies almost immediately. The male lives only for a short while after this. The eggs are then tested for disease. If they are disease free they are then raised in a controlled environment. The eggs are fastened to a flat surface by a substance that is secreted by the female. The larvae hatch out of the eggs in about 10 days and are about a half a centimeter long. After the larvae hatch they are placed under a layer of gauze. Afterwards, they are fed a large amount of cut up mulberry leaves. During this time they are left to shed their skin, which they do about four times during the process. Sometimes they'll feed the larvae orange juice or lettuce. The larvae that are fed the mulberry leaves are the ones that produce the finest silk. Each larvae can eat over 50,000 times its size in food. After the larvae has reached its maximum length, which is about 7.5 centimeters, it stops eating. This takes about four to six weeks. After this happens it changes color and attaches itself to some kind of object like a frame, tree branch, twig or shrub. Once attached, they start spinning their silk. This goes on for about three to eight days. This is where the hard work by the silkworms comes in. Over the next few days, the silkworm produces a thread by making a figure eight motion over 300,000 times, during which time it is actually constructing a cocoon. This is a non stop process. The cocoon is made because this is where the silkworm plans to live during what is called its chrysalis stage. During this stage it sleeps and sheds its skin. During this stage, which lasts about sixteen days, the silkworm begins the next process of turning into a moth. The problem, for the silk manufacturer, is if the pupae remains alive it will secrete a substance that will destroy the cocoon, thus ruining the silk threads. To prevent this from happening the pupae are killed. This is why activists have such a problem with the process. The truth is, the percentage of silk that is actually saved in this process is very small. Thousands of pupae die. It takes about 80 kg of cocoons to produce just 1 kg of raw silk.

With all of us feverishly trying to keep up with the latest fads Hollywood exports, finally there is a fashion tip that will truly enhance our lives. Recently, Tom Cruise’s former sidekick Nicole Kidman was quoted by the Associated Press as saying: “I wish that I hadn’t been born with red hair and fair skin” as she is concerned about the amount sun exposure and its direct link to an increased risk for skin cancer. She should know, too. After all, she hails from Australia where skin cancer is an exploding epidemic. Subsequently, Australia is the leading the world in heightening the quality of skin cancer prevention education and proactive sun safety behavior. Truth be told, skin cancer is the world’s most common cancer. Americans are no exception to the rule either! Every hour someone in the United States dies from skin cancer, according to the American Academy of Dermatology (www.AAD.org). Perhaps, Kidman’s example will encourage the propagation of a new fashion wave - sun protective clothing. Whereas, sun protective clothing (also known as ultraviolet radiation protective clothing; or “UVR”) is widely used in Australia, Europe, and South Africa, it is still relatively unknown here in the U.S. Sun protective clothing, however, is a highly effective option for individuals to protect themselves from the harmful affects of UV-rays all day, every day. If you consider that the average white 100% cotton t-shirt is equivalent to only a SPF 6 (which provides about 14% worth of sun protection), clearly there is a need for light-weight, functional, stylish, economical, clothing that also provides exceptional protection from over-exposure to the sun. On the other hand, sun protective clothing blocks out more than 97.5% of UV rays (which is an equivalent to a SPF 30 sunscreen). This is considered by the Skin Cancer Foundation to be “the best of the best” as it were when it comes to effective sun protection. If you consider that a SPF 20 sunscreen is allowing only five out of every 100 UV protons to reach your skin; it is 95% protective, than sun protective clothing is quite simply the most revolutionary new product available on the market today for those looking for a viable, yet extremely effective, way to protect themselves and their loved ones from sun damage. Dermatologist-oncologist, Sancy A. Leachman of the Tom C. Mathews Jr. Familial Melanoma Research Clinic at The Huntsman Cancer Institute (www.HuntsmanCancer.org) recommends that everyone use a sunscreen with a sun protection factor of 15 for daily, year-round use; SPF 30 is recommended if we are outdoors between 10:00 a.m. and 4:00 p.m. when UV rays are most intense. SPF 30 sunscreen is also highly recommended for those of us who possess multiple risk factors for skin cancer such as blonde or red hair, blue or green eyes, fair or sensitive skin, many atypical moles, and even family history of skin cancer – like Nicole Kidman. Wearing sun protective clothing, coupled with proper year-round use of sunscreens, is the quite simply the best protection available, Sancy says. And her colleagues in the field of dermatological medicine agree. “Appropriate sun apparel should offer effective protection against both short term and long term photo damage [such as wrinkling, skin cancer, and even cataracts],” says Dr. J.M. Mentor, who also teaches dermatology at the Morehouse School of Medicine (www.MSM.edu). In other words, effective sun safety apparel ought to protect against both UV-B and UV-A rays, and sun protective products such as those specially manufactured by Stingray in Australia, do exactly that. Stingray is the original sun protection clothing company to specialize in UV protection swimwear and daily attire for children and adults. “As a result of listening to the needs of our many customers, we are able to deliver products that take the ‘sting out of the sun’s rays,’” says Wendy Lister, Managing Director of Stingray. “[People] are now getting the best possible UV protection.” Those living at high altitudes or near the equator, have the highest risk in for skin cancer, according to the American Academy of Dermatology. Glen and Liisa Tomson, both natives of South Africa, know first-hand the devastating toll sun damage can take on our health. As such, they have recently partnered up with The Cancer Crusaders Organization (www.CancerCrusaders.org) in a five-year international skin cancer prevention education campaign called “Only Skin Deep?” This program aims to actively engage parents and young adults in the fight against the world’s most common, yet preventable, cancer. “We see a great and pressing need for increased awareness and education here in the U.S.,” says Glen Tomson. “Too many times my wife and I will be at the pool, and see all these children running around sun burnt. Often, we’ll offer shade [clothing] and sunscreen to the parents so they can better protect their children.” Glen and Liisa, in addition to being entrepreneurs and experts, are parents and realize the importance of instilling the practice of sunscreen usage and the wearing of sun protective clothing at a young age so as to develop a lifelong habit of sun safety behavior. In fact, the American Academy of Dermatology reports that sustaining just one severe “blistering” sunburn before age 18 increases one’s likeliness of a future skin cancer diagnosis by an estimated 60%. In other words, 80% of one’s lifetime skin damage occurs in the first 18 years of life. This is of particular concern the mountain states where high elevation exposes us to more intense UV irradiation. Dr. Leachman illustrates it best by saying, “Someone standing on the summit of Mt. Timpanogos [Utah] will burn 66-to-77 times faster than someone standing on a beach in Los Angeles [California].” Lechman adds, “Skin cancer incidence is increasing at an alarming rate here in the United States, so it is important that we all take proper precautions to protect ourselves.” The AAD solidifies Leachman’s remarks, reporting 1.3-million Americans will be diagnosed with some form of skin cancer this year. The risk is real,” Leachman says. “There is a real need for people to take necessary precautions and to teach patients how to advocate for themselves [in reducing their risk for skin cancer].”

What is a fossil? While this is a simple question, the answer can be simple or a bit more complicated. The short and sweet answer to that question is “A fossil is the remains or evidence of any creature or plant that lived on the earth in a past geologic age.” But there are so many KINDS of fossils. A more important question for a curious student is “What kinds of fossils are there?” The answer to that question will take a bit more exploration. You’ll have to dig a little deeper…pun intended! The Long Answer There are several fossil classification systems in use today, but the one that I like the best is the one used by Peter Larson and Kristin Donnan in their book, Bones Rock! They group fossils into two categories: Type I-the remains of the dead animal or plant or the imprint left from the remains. Type I includes:

• bones
• teeth
• skin impressions
• hair
• the hardened shell of an ancient invertebrate (an animal without a backbone) like a trilobite or an ammonite
• impression of an animal or plant, even if the actual parts are missing.

So now you have one short and one long answer to the question: "What is a Fossil?" Let's build on that. Type II- Something that was made by the animal while it was living that has hardened into stone. These are called trace fossils. Type II includes:

• footprints
• burrows
• coprolite or animal poop

Type I fossils can be the actual thing that it once was, like a piece of bone or hair or feather. More often the bone material is replaced by different minerals contained in the liquid of the sediments that buried it. What was once bone is now some sort of crystal or mineral. This process also takes place with shells, exoskeletons and wood. If the spaces in the bone are filled with liquid minerals which later harden it is called permineralization. Sometimes the organic material is dissolved by the mineral-laden water. The process happens so slowly that each cell is dissolved and replaced by a particular liquid mineral before it hardens. This is called petrification. In petrification, every detail down to the cellular level is duplicated in the minerals. Type I can also be molds or casts of the original animal or plant part. If the original organism decays, leaving an imprint and an empty space, it is called an exterior mold or simply a mold. If a space in the structure is filled with minerals as the original animal or plant part dissolves, it is called a cast. So now you have the short answer and the long answer to the question "What is a fossil?” Was that more info than you were seeking? I hope not! Fossils are the illustrations on the pages of rock that are the earth’s history. I think the more you know, the more you’ll want to discover about these fascinating traces of life we call fossils.

Chemistry is generally divided into two broad branches: organic chemistry and inorganic chemistry. Other types of chemistry include physical chemistry, biochemistry, and analytical chemistry, with each field branching off into several specific subfields. Here’s a brief description of the most common branches of chemistry. Organic Chemistry Organic Chemistry has to do with the study of compounds that contain carbon (and sometimes hydrogen). Even though carbon is only the fourteenth most common element on the planet, it produces the greatest number of different compounds on Earth. Not surprisingly then, much of the study of chemistry involves organic chemistry. The most studied groups of organic compounds are those that contain nitrogen. These organic compounds are important because they are often linked to the amino group. When the amino group combines with the carboxyl group, amino acids are born. Amino acids are important because they are as the building blocks of proteins. Inorganic Chemistry Inorganic chemistry involves the study the properties and reactions of compounds that do not contain carbon and which are not organic. Inorganic chemistry studies all non-living matter, such as minerals found in the Earth’s crust. There are many branches of inorganic chemistry, including geochemistry, nuclear science, coordination chemistry, and bioinorganic chemistry. There is much overlap between organic and inorganic chemistry. For instance, organometallic chemistry studies the use of compounds that are capable of creating a covalent bond between carbon and metal. Physical Chemistry As its name implies, physical chemistry has to do with the physical properties of materials. Physical properties that are studied may include the electrical and magnetic behavior of materials, as well as their interaction with electromagnetic fields. There are several subcategories of physical chemistry. These include thermochemistry, electrochemistry, and chemical kinetics. Thermochemistry studies the changes of entropy and energy that naturally occur during chemical reactions. Electrochemistry is concerned with the study of interconversions of electric and chemical energy of matter, as well as the effects of electricity on chemical changes. Chemical kinetics involves the study of chemical reactions. Specifically, chemical kinetics studies the equilibrium it reached between products and their reactants. Biochemistry Biochemistry is a branch of chemistry concerned with the composition and changes of living matter. Biochemists commonly focus on the physical properties and structures of biological molecules. Common biological molecules include carbohydrates, proteins, lipids, and nucleic acids. Biochemistry is sometimes referred to as physiological chemistry and biological chemistry. Biophysics, molecular biology, and cell biology are research fields closely related to biochemistry. Analytical Chemistry Unlike the other main types of chemistry, analytical chemistry doesn’t deal specifically with specific elements. Analytical chemistry is concerned mainly with the various techniques and laboratory methods used to determine the composition of materials. Qualitative and quantitative analysis are the two most basic methods used in analytical chemistry. Qualitative analysis has to do with identifying all the atoms and molecules in a sample of matter, with attention paid to trace elements. Quantitative analysis also involves determining the atomical and molecular structure of matter, but includes also measuring the exact weight of each chemical constituent.