More Evidence that the Moon Came from the Earth

Will et al. Indigenous noble gases in the Moon’s interior. Science Advances, Aug 2022.

Humankind has always been fascinated with the Moon and studying it for nearly five centuries since Galileo. A recent discovery now adds new evidence to the currently favored “Giant Impact” theory which hypothesizes that the Moon was formed by a massive collision between Earth and another Mars-sized celestial body around 4.5 billion years ago. A group of researchers examined six samples of lunar meteorites collected in Antarctica using an exceptionally sensitive mass spectrometer and found that the meteorites contained noble gases like Neon and Helium, consistent with those found in the Earth’s mantle. Researchers proposed two possible scenarios for how the noble gases became trapped in the Moon’s interior. In the first scenario, impactors got mixed with the lunar mantle during cooling of the magma oceans to solidify over few million years of the Moon’s formation. In the second scenario, the Moon has been formed from a debris field surrounding the Earth where noble gases were directly mixed into the Moon’s interior mass. Discovery of noble gases on the moon may also inform us about its water content, too. If these gases are still there, then water could also been present in the Moon’s interior. Such water resources could be an invaluable resource for future human missions. More broadly, this study suggests that a wide variety of life-forming material can survive giant impacts early in a planet’s life. We now could make more reliable models of how planets and solar systems form and even how life is originated on the Earth.

Restoring cell functions after death?

Andrijevic et al. Cellular recovery after prolonged warm ischaemia of the whole body. Nature, August 2022.

Organ transplantation is an extremely complicated medical process. There is a massive shortage of donor organs. Waiting lists are long. Even if a patient is lucky to match with a donor organ, getting that organ before it dies through cell damage has been a big challenge. A new technology may offer a solution to extend the time that donor organs survive. A group of researchers has recently developed a technology called OrganEx, which can restore cellular activity even after death. Very shortly after the death of an organism, all cells start to die and organs begin to fail. The researchers worked with one hundred pigs to see whether cellular structures could be saved, or cell damage could be reversed, when OrganEx is applied after death. OrganEx has two major components. First is a device that simulates the heart and lung function by pushing a mix of blood and a drug cocktail to the organs. Second is the drug cocktail made of 13 chemical compounds. One hour after death, the pigs were hooked up to the OrganEx machine which pumped the cocktail to the animal’s organs for six hours. The results were striking; OrganEx could restore critical cell functions after death. While this is a huge step for organ preservation, researchers still have to make more tweaks for the technology to be used in humans. Once fully developed, OrganEx is expected to keep organs outside the body for long-term or transported longer distances.

Sweat-powered wearable electronic devices

Liu et al. Microbial biofilms for electricity generation from water evaporation and power to wearables. Nature Communications, July 2022.

Researchers have developed a biofilm that sticks to the skin like a Band-Aid to harness sweat for electricity that could power wearable devices. The biofilm is made using a type of bacteria called “geobacter sulfurreducens” known for its ability to produce electricity. In this biofilm design, bacteria convert energy from evaporation into electricity by using the moisture on a person’s skin. Most strikingly, researchers found that the biofilm bacteria do not need to be fed because they are dead! They do not need to be alive to produce electricity. The biofilm consists of thin sheets of bacteria colonies (thickness less than 0.1 millimeter) that is sandwiched between two mesh electrodes and sealed with a soft, sticky biopolymer to enable it to grip to the skin. Sticking this biofilm on your skin is like plugging in a battery. This technology has potential to revolutionize wearable electronics by solving the major problem of power supply. Moreover, this is a real green energy-driven device made naturally by the microbes and devoid of any unsustainably produced materials and toxic waste byproducts. The current version of the biofilm can produce enough energy to power small devices such as medical sensors or personal electronics, but the researchers hope to explore larger films that can power even more sophisticated devices.

Smart prosthetic hand combines both human and robot control

Zhuang et al. Shared human–robot proportional control of a dexterous myoelectric prosthesis. Nature Machine Intelligence, September 2019.

Holding an object in your hand might seem easy, but it’s actually a very complicated and challenging task; if, for instance, an object starts to slip, you typically have a couple of milliseconds to react. Scientists have been trying new approaches for improved control of robotic hands, particularly for use by amputees. A recent technology was able to combine individual finger control and automation for improved grasping and manipulation by successfully merging the fields of neuroengineering and robotics. This interdisciplinary approach was tested on three amputees and seven non-amputee subjects. The neuroengineers achieved the intended finger movement from muscular activity on the amputee’s stump, allowing for individual finger control of a prosthetic hand, which had never been done before. The robotics team enabled the robotic hand to take hold of objects and maintain contact with them for robust grasping. The amputee first performed a series of hand movements in order to train the algorithm through a machine learning paradigm. This taught the algorithm to decode user intention and translate it into finger movements of the prosthetic hand. Concurrently, sensors placed on the amputee’s stump detected muscular activity, which trained the algorithm to learn which hand movements corresponded to which patterns of muscular activity. Once the user’s intended finger movements were acquired, this information could then be used to control individual fingers on the prosthetic hand. When the user tried to grasp an object, the robotic automation initiated. The algorithm told the prosthetic hand to close its fingers when an object was in contact with sensors on the hand’s surface. This automatic grasping was designed to infer the shape of objects and grasp them based on tactile information alone, without any help of visual signals. The robotic hand has the ability to react within 400 milliseconds, and it is equipped with pressure sensors all along the fingers: it can react and stabilize the object before the brain can actually perceive that the object is slipping. While this promising technology can be used in in several neuro-prosthetic applications such as bionic hand prostheses and brain-to-machine interfaces, there are still many challenges remaining to implement this technology in a commercially available prosthetic hand for amputees. It is currently being tested and improved.

Cats securely bond with people, too

Vitale et al. Attachment bonds between domestic cats and humans. Current Biology, September 2019.

Dogs have long been regarded as man’s best friend. They’re sociable, faithful, and obedient. Cats, on the other hand, are often described as more aloof, mysterious, and independent. But a new study suggests that cats actually bond with their owners in similar ways to how humans and dogs bond with companions. The most established way to study human attachment behavior is to observe an infant’s response to a reunion with their caregiver following a brief absence in a novel environment. When a caregiver returns, secure infants quickly return to relaxed exploration while insecure individuals engage in excessive clinging or avoidance behavior. These tests had been previously run with humans, primates, and dogs; researchers decided to run the same test with cats. 79 kittens and 38 adult cats and their caregivers were recruited. During the test, an adult cat or kitten spent two minutes in a novel room with their caregiver followed by two minutes alone. Then, they had a two-minute reunion. The cats’ responses to seeing their owners again were classified into attachment styles. The results show that cats bond in a way that’s surprisingly similar to infants. In humans, 65% of infants are securely attached to their caregiver and domestic cats and kittens mirrored this, as about 65% of them securely bonded to their people. After the first round of tests, the researchers enrolled half the kittens used in the study in a training and socialization course. The other half served as a control group. Researchers then found the same results, suggesting the training did not have an effect on kittens’ attachment behavior toward their owners. This indicates that once a cat forms a bond, it seems to remain stable over time. This social flexibility may have helped facilitate the success of the species in human homes. It is still not clear what the factors are that shape the caretaker relationship, but it’s likely a miraculous complex mix of genetics, personality, and experience.

An efficient and green way to convert heat into electricity

Zheng et al. Paramagnon drag in high thermoelectric figure of merit Li-doped MnTe. Science Advances, September 2019.

A recent discovery could help scientists to develop more efficient ways to generate electricity from heat that would have been otherwise wasted, such as heat coming from car exhaust, industrial processes, and interplanetary space probes. In principle, magnetic fields can be used to generate electricity. If we move a magnet through a coil or wire, the magnet pushes and pulls electrons that create an electrical current. Magnets themselves don’t have energy, but they can control energy currents through the created magnetic field. The main problem with magnets is that when a magnet is heated up, it loses most of its magnetic properties and becomes a so-called paramagnet. Until this discovery, scientists believed that paramagnets couldn’t be used for generating electricity. In the new study, researchers found a way of designing thermoelectric semiconductors that can convert heat to electricity. The tiny particles in paramagnets, so called paramagnons, ended up producing enough spin to push an electron, for only a billionth of a millionth of a second – apparently long enough to make paramagnets viable energy-harvesters. This breakthrough in the conventional understanding of magnetic properties could lead to more research into how magnets and energy interact to potentially facilitate electricity production from heat that is otherwise wasted and oftentimes harmful to the environment.

{module Science Square (Issue 128)}

First miniature human heart printed

Noor N et al. 3D Printing of Personalized Thick and Perfusable Cardiac Patches and Hearts.  Advanced Science, April 2019.

In a major breakthrough, researchers have “printed” the world’s first 3D vascularized engineered heart using a patient’s own cells and biological materials. This could have huge repercussions for human health: the World Health Organization said that last year, ischemic heart disease and stroke were the world’s leading cause of death for both men and women. Heart transplantation is currently the only treatment available to patients with end-stage heart failure. Given the serious shortage of heart donors, scientists have been trying to develop new “3D organ printing” approaches to regenerate the diseased heart. Past studies were only able to print simple tissues without blood vessels. The new study showed for the first time that an entire heart with cells, blood vessels, ventricles, and chambers could be successfully engineered and printed. The researchers first took a biopsy of fatty tissue from patients and separated the cellular and a-cellular materials of the tissue. While the cells were reprogrammed to become pluripotent stem cells, the extracellular matrix – a 3D network of extracellular macromolecules such as collagen and glycoproteins – were processed into a personalized hydrogel that served as the printing “ink.” After being mixed with the hydrogel, the cells were then robustly differentiated to cardiac or endothelial cells to create patient-specific, immune-compatible cardiac patches with blood vessels and, subsequently, an entire heart. The heart was 3D-printed in about three hours and was too small for humans. It was the size of a rabbit’s heart (~ 2.5 centimeters). But it is completely biocompatible and, most importantly, matches the patient, which reduces the chances of organ rejection inside the body. A human-sized heart might take a whole day to print and would require billions of cells, compared to the millions used to print these mini-hearts. While it’s not clear if a printer can produce hearts that are equal or superior to human ones, perhaps by printing patches there will be a possibility to improve or take out diseased areas in the heart and replace them with something that works. Researchers hope that maybe in 10 years, there will be organ printers in the finest hospitals around the world, and these procedures will be conducted routinely.

Bacterial factories for spider silk

Zhang F et al. Synthetic Biology for Microbial Production of Protein-based Materials, the American Chemical Society (ACS) National Meeting & Exposition, Spring 2019.

Spider silk has always fascinated researchers due to its lightweight and superior strength and numerous applications in areas such as drug delivery, smart textiles, and artificial muscles. It is one of the strongest natural materials in the world. It is thinner than a human hair, but its strength is more than that of steel, pound for pound. Since farming spiders is incredibly inefficient, scientists have been trying for decades to find a way to mass produce the material from genetically modified bacteria, yeast, and even goat milk, but these efforts have always fallen short. The biggest challenge was that the genetic information for dragline silk is a long string of repeating DNA, and, in previously tested organisms, cellular machinery arbitrarily alters or chops up such DNA sequences. To circumvent this problem, researchers precisely separated the repeating DNA into bits and inserted each repeating piece separately into bacterial genome. These smaller DNA pieces produced small peptides that ended up combining in bacteria and formed a strand of silk. The researchers also added to the end of each strand a chemical tag that glued the individual fibers together. This method was able to produce 2 grams of spider silk for each liter of bacteria and the resulting material behaved exactly like dragline silk. Its tensile strength was measured at 1.03 gigapascals, about the same as for naturally produced dragline silk. The engineered silk’s toughness measured 114 megajoules per cubic meter, compared with around 100 megajoules for silk made by spiders. And the engineered silk strands could stretch 18 percent before breaking, the same as natural dragline silk. The new silk was developed in part with NASA funding for applications such as giving astronauts a means of producing tough materials while on Mars. But the substance could be used in designing stronger materials for robotic, medical, or textile applications.

Electricity from falling snow

Ahmet A et al. All printable snow-based triboelectric nanogenerator. Nano Energy, April 2019.

Researchers have designed a new device with which we can now obtain electricity from falling snow. This new energy conversion method could become a new source of electricity in the future, especially in remote areas, as it does not need batteries. Researchers called it a Snow-based TriboElectric NanoGenerator, or Snow TENG. It is inexpensive, small, thin, and flexible like a sheet of plastic. After starting a charge from static electricity, energy is generated from the exchange of electrons. Snow is already positively charged by giving up its electrons, while silicone, a rubber-like material which consists of silicon atoms and oxygen atoms, is combined with carbon, hydrogen, and other elements to be negatively charged. When the positive-charged snow falls onto the surface of the silicone, the charges interact, and the Snow TENG captures the charge, which allows it to turn snowfall into electricity. 30% of Earth’s surface is covered by snow each winter, which is also the time when solar panels, one of the most reliable renewable sources of energy, aren’t very effective. Snow accumulation reduces the amount of sunlight that reaches the solar array, which makes them unable to operate. Snow TENG could be integrated into solar panels and provide a continuous power supply, even at a time when it’s snowing. Researchers used 3D printing to design the small device. It consists of a layer of silicone and an electrode which can capture the electric charge. Given that silicone is widely used in the industry, this method could dramatically reduce the global costs of producing electricity.

The heart is composed of four compartments: two atriums and two ventricles. The blood that reaches the heart first accumulates in the atriums. From here, it is sent to the ventricles. Afterwards, it is redistributed to the body by the contractions of the ventricles. The harmony of this process depends on the electrical currents in our hearts.

How is the electrical current formed?

There is a particular region in the heart called the sinus node. The sinus node is strip of a muscle that is 15 mm in length, 3 mm in width, and 1 mm in thickness, and is located in the right atrium of the heart. The cells of this strip are responsible for producing electrical currents, and are created in a different fashion from the rest of the cells that are responsible for producing contractions. This is where the electrical currents in our hearts are periodically produced. Every cell in the body contains elements such as sodium, calcium, potassium and chlorine that are electrically charged. The elements which are electrically charged are called ions. These ions also exist in the extracellular environment. The intra cellular and extra cellular concentrations of these ions are different from each other. This situation causes a difference in the electrical potential between the interior and exterior of a cell. This difference is called a membrane potential. Periodically, the membrane potentials of the sinus cells show sudden jumps – meaning they suddenly increase and then suddenly decrease. Since the cells are in close contact with each other, such a jump in the membrane potential of one cell triggers a jump in the membrane potential of another cell. The electrical currency that enables the contraction of the heart is produced by this continuous triggering of cells. On average, 70 electrical currents per minute are produced in the sinus node. These currents start being produced while a person is in the womb of their mother and continues their whole lifetime. The heart of an embryo starts beating while it is only 22 days old. However, the height of the embryo at this point has not even reached 1 cm. Isn’t it an amazing force that creates the beating heart of such a small embryo and keeps it going a lifetime?

How is the electrical current distributed?

Another node called the atrio ventricular node was created in between the atriums and ventricles in our heart. While the current coming from the sinus node is spread to the whole of the atrium, it is by this node that the current is sent to particular fibers. The task of this node is to hang on to the current coming from the sinus node for a while. Why does the current need to be held on to? Because blood can only enter the ventricles while it is resting and by holding on to it, the contraction of the ventricles is disabled while the contraction of the atriums is taking place. By this process, the blood coming from the atrium can enter the ventricle. Therefore, the blood fills in the ventricles and can be distributed throughout the body. The blood circulation is enabled in a flawless manner by allowing the atriums to do their duty while the ventricles wait.

After passing through the atrio ventricular node, the electrical currency eventually goes through the purkinje fibers. These fibers surround the ventricles like a web and are composed of cells that can conduct electrical current in a very fast manner. Compared to the atrio ventricular node, the electrical current can be conducted 150 times faster in the purkinje fibers. Therefore, the current reaches every point of the ventricles in a very short period of time. Every muscle in the ventricles contracts in a time shorter than one tenth of a second.

The muscles in the ventricles rapidly contract, one by one, depending on when the current reaches them. The contraction starts at the end of the ventricles and carries on towards the main veins exiting the heart. By this orderly and harmonious contraction, the blood is pumped from the end of the heart towards the main veins exiting the heart to be distributed among the body. Because all the ventricle muscles are stimulated very fast, the contraction also happens very fast, resulting in a strong pumping effect. The design of this system is incredibly wise, right down to its most minute detail.

Movement in heart muscle potential

As all cells in our body, the cells in the heart also have a membrane potential. We had stated before that this membrane potential is the result of the difference in intra and extra cellular ion concentrations. The charges of these ions are different from each other. For example, sodium and potassium have plus one (+1) charges, calcium has a plus two (+2) charge, and chlorine has a negative one (-1) charge. The resting potential of a cell is negative. This means that there are more negative ions within the cell when compared to its environment. Sodium, calcium, and potassium ions are mobile through the membrane. While sodium and calcium have a higher concentration outside the cell, potassium has a higher intra cellular concentration compared to its environment. There are channels created on the cell membrane that allow ions to pass through the membrane. The sudden increase in the membrane potential that was explained before causes a sudden rush of sodium ions inside the cell. This is such a rapid movement that it is concluded in a tenth of a second. Right after the entrance of the sodium ions, calcium ions also enter. Because these ions are positively charged, the membrane potential becomes positive.

With the entering of calcium ions into the cell, calcium ions are also released from the storages within the cell. By triggering the protein necessary for these contractions, the calcium ions become a means for the contraction of the heart muscles. Meanwhile, the potassium channels open and these ions within the cell pass to the extra cellular environment. The loss of positive ions results in the membrane potential being negative again. Therefore, the sudden jump in membrane potential that is the basis for the electrical current is created.

However, at this point there are extra amounts sodium and calcium within the cell and extra amounts of potassium outside the cell. The concentrations need to be returned to their original values for the next jump in the membrane to be possible. This task is given to a protein called the sodium-potassium pump that pumps out sodium from the cell and pumps in potassium. If this pump had not been created, the ion balance in any of the cells within the body would be impossible to re-establish. As a result, the life of the cells would come to an end. However, because of the remarkable intricacy of our cells, life is made possible for us.

Afterwards, some amount of the calcium ions are pumped out of the cell with a similar pump, while the rest are stored within the cell. The decrease in the concentration of calcium relaxes the muscle. Now the heart muscle has gone into relaxation and therefore is ready for the next contraction.

If the movement of the ions becomes unbalanced, the rhythm of our heart is disturbed. The unbalance in the ion movements or blockage in heart veins can be reasons for heart rhythm disorders. Even small heredity-based defects in the ions pumps affect the movement of these ions and can cause heart rhythm disorders. This situation shows that nothing is created by coincidence.

Movement in the sinus node

The jump in the membrane potential of a heart cell depends on the membrane potential jump of the previous cell. Through the gaps in between the cells that are in contact with each other, the positive ions that exit a cell reach the membrane of the cell next to it and trigger the opening of its ion pumps. As a result, the membrane potential of that cell starts changing. At this point, you may have this question: how does the electrical current start in one end of the sinus node that is not previously triggered by any cell?

This concept is explained by the ion transfer mechanism of the node cells being different than the muscle cells. Before explaining this, it should be noted that even while resting, a mechanism for allowing an ion exchange of the cell with its surrounding has been created. In the node cells, this exchange while at rest has been created in a way that the sodium and calcium exchange is larger and the potassium exchange is lower compared to the muscle cells during resting conditions. Therefore, the membrane potential of the node cells is less negative and slowly increases with time. As a result of this slow but steady increase, after a while it reaches a threshold. When it reaches it, the calcium channels in the membrane suddenly open and there is a rush of calcium ions into the cell. Thus, the jump in the membrane potential is created independently from another cell.

As it can be observed, even a single contraction of our heart depends on a very detailed, delicate, and complex system. Moreover, this system is repeated over a hundred thousand times within one day. After reflecting on this, how can we claim this system runs by coincidence or chance?

What does sustainability mean? According to the definition by the World Commission on Environment and Development, sustainability means meeting the current needs without compromising the ability of future generations to do the same. Sustainability embraces more than just the environmental concerns; it also includes both social and economic factors. Thus it provides a holistic and inclusive foundation from which to operate.

Why care about sustainability anyway? It is because our very own life depends on clean air, drinkable water, arable land, other species and one another to exist. After all, if we are not breathing air, drinking water and eating plants or animals, we are not living. We are all part of a system, whether on a local or global scale. In order to make choices that will help us to improve our quality of life, we must first understand sustainability and the environmental issues present in our daily lives and how our actions are related to those issues. Once we understand our contribution to the problem, we can then begin to make decisions that will help, not harm, our planet, our future generations and ourselves (Worksbook, p.10).

As Pope John Paul II stated “Modern society will find no solution to the ecological problem unless it takes a serious look at its life styles.” If we categorize our life style in a way that helps us analyze the environmental impact of our choices, we might end up having three main categories: Water, Energy, and Waste. This article focuses on the problems related with those categories and the solutions that can be done on a personal level.

Water

“By means of water, we give life to everything.” (Al-Anbiya, 21:30)

Water is very precious, yet it is very scarce. Even though water covers two thirds of the surface of our planet, the freshwater in rivers, lakes, and streams represent only 0.02% of the earth’s total water (United States Geological Survey). According to an estimate from the United Nations, by the year 2025, around 2 million people will be living in regions with absolute water scarcity, and two out of three people on earth could be living under conditions of water stress if nothing is done. So, what can you do about it? According to the Sustainability Primer Works Book, the things you can do include finding and fixing the leaks around your home; because leaking faucets and toilets can account for as much as 20 gallons of water lost per person per day (Treehugger team, 2006). You can also install water saving devices, because high efficiency toilets and showerheads can save the average household about 30 gallons of water each day (Walsh, 2009). A low flow high efficiency showerhead uses 2.5 gallons of water or less per minute, whereas traditional showerheads use 5 gallons or more per minute. The top priority is changing your behavior. Simply turning off the water while shaving or brushing teeth could save more than 5 gallons (19 liters) of water per day. Keeping a bucket or large pitcher in the bathroom or kitchen to capture the excess water while you are waiting for the hot water to make it to the faucet can get you enough water, which can be used for your pets, plants, to wash produce etc.

Energy

“To warn of the dangers is not to despair of the solutions.” Al Gore

Much of the world’s current energy production is unsustainable. The burning of fossil fuels such as coal and oil to produce electricity depletes non-renewable resources, and releases pollutants that contribute to smog, acid rain and other types of air pollution. Electricity production is indeed the leading cause for industrial air pollution. Replacing your incandescent bulbs with more energy efficient Compact Fluorescent Bulbs (CFLs) or Light Emitting Diodes (LEDs) can be a good start to go green for energy around your house. Lighting accounts for up to 25% of home electricity use (California Energy Commission). CFLs use one-fourth the energy of standard incandescent bulbs to give out the same amount of light, and they last ten times longer. LEDs may even last 50 to100 times longer than the standard light bulbs. According to the US department of Energy: “If every home in America replaced just one incandescent light bulb with an ENERGY STAR qualified CFL, it would save enough energy to light more than 3 million homes and prevent greenhouse gas emissions equivalent to those of more than 800,000 cars annually.”

You can also pay attention to heating and cooling in your home.

Basic things like changing the filter, putting on a sweater instead of turning on the heater, and setting the thermostat appropriately might save up to 10% off your electricity bill. Think about buying energy saving appliances when you need to buy new ones, simply look for the signs like ENERGY STAR. Also, shut off appliances whenever possible. The U.S. Department of Energy recommends using “standby-mode” when our computers will be idle for more than 20 minutes. It also points out that 75% of electricity used to power home electronics is consumed when these appliances are “turned off.” You can use a power strip to turn everything completely off when finished for the day.

Waste

“Waste not want not!” Benjamin Franklin

World economies operate on a take, make, waste model, which is a one-way linear production system in a finite world. The problem with this system is that it operates as though everything were in infinite supply. But this is not the case for our limited resources. Our current practices for waste generation create significant environmental, economic, and public health problems. Generally, the public is unaware where our trash ends-up, and what it causes there. Landfill, also known as a dump, is a site for disposal of the wastes by burial. A large number of adverse impacts may occur from landfill operations. One is serious pollution of the local environment such as contamination of groundwater and/or aquifers by leakage and residual soil contamination during landfill usage. Another is after landfill closure; the generation of methane by organic waste decay (methane is a greenhouse gas many times more potent than carbon dioxide, and can itself be a danger to inhabitants of an area.) Then there are simple nuisance problems such as dust, odor, vermin, and noise pollution.

The problem is not only what we do with waste but also what we waste. According to United States Department of Agriculture, over a quarter of the country’s food that is approximately 25.9 million tons, gets thrown away every year. On the other hand, the number of cell phones Americans tossed out in 2008 is 130 million (Larry Greenemeler, 2009). Recycling them would have saved enough energy to power 194,000 homes for a year. The current U.S. recycling average for the so-called e-waste, including unwanted cell phones, televisions, PCs, computer peripherals, computer mouses, keyboards and many others, is in the order of 10 to 13%. Sustainability Primer points out the things you can do about waste issues. These include but are not limited to reducing how much you consume and to reuse items whenever possible, to bring your own reusable bag, and reuse paper and plastic bags. Reuse paper and envelopes at home or in the office. Recycle office supplies like printer cartridges, toner etc. At home, recycle everything you can or collect for hazardous household waste. You can also give away or donate things that you don’t use. Like the “good old times,” repair instead of discard, purchase well designed quality items that last longer. Try to recreate the old-good habit of borrowing and sharing the resources among neighbors and family. It may take some effort but start composting your food waste. In addition to all above, the best thing you can do is “close the loop” by purchasing products made from recycled materials.

All things considered, does it seem like you need to suffer at all to go green?

If we want to change the way things are going, we should listen to what Gandhi said, “I must be the change I wish to see in the world around me”. Living in balance with nature requires understanding the value of the bounties we take for granted. Because “In the end, we will conserve only what we love. We will love only what we understand and we will understand only what we are taught” Baba Dioum.

References

• Sustainability Primer Works Book, Worksbook, Community Partners/Sustainable works, Los Angeles, 2009-2010 Update, SMVersion 9.0.
• Treehugger Blog, “How to green your water,” December 03, 2006. www.treehugger.com
• Walsh, B. “Getting real about the high price of cheap food,” Time Magazine, Aug 21, 2009.
• California Energy Commision, http://www.energy.ca.gov/efficiency/lighting/
• Division of Information Technology, UW- Madison “Turn off your monitor to save energy? Do it.” December 29, 2005 http://www.doit.wisc.edu/news/story.asp?filename=598
• Greenemeler L. Scientific American blog, comment on Trashed Tech: Where Do Old Cell Phones, TVs and PCs Go to Die?, November 29,2009 http://www.scientificamerican.com/article.cfm?id=trash-tech-pc-tv-waste

Our current source of energy is mostly fossil fuels such as oil, coal, and natural gas. Fossil fuels are nonrenewable. In other words, they are finite resources and they will diminish significantly in future; hence, they will be very expensive to use and environmentally harmful to recover. In contrast, solar, wind, biomass, hydrogen, geothermal, ocean, and hydro power are renewable energy resources, that is, they are constantly replenished and will not run out. Renewable energy is not only important for our energy needs but also has significant advantages over fossil-based energy resources in the protection of the environment. Besides, the environmental aspect of renewable energy also has a religious dimension, since preservation of the earth and its inhabitants is regarded as a duty for humankind.

Among these energy resources, solar energy is generally used for electricity generation or for hot water heating. It also finds uses in solar cooling, and in direct heating and lighting of buildings and homes. Solar panels are made of photovoltaic (PV) cells. The term “photovoltaic” means “converting light into electricity.” Solar energy technology has been around since the late nineteenth century. Yet, its share in energy production constitutes a very small fraction (less than 0.1%) of production around the world. This stems from the higher cost of electricity generation with solar panels in comparison to use of fossil fuels. In the US, electricity generated from PV cells costs $0.30 to $0.40 per kilowatt-hour while consumers pay only $0.10 per kilowatt-hour to the electric utility companies. Nonetheless, with recent advances in this technology, it will be possible in the near future to decrease the cost and make this technology viable for our energy needs as we face shrinkage in fossil fuels around the globe.

One of the factors that increases cost is the low power-conversion efficiency of current PV cells. The PV cells used in the market are mostly fabricated from silicon crystals and these cells show a power conversion efficiency of 15%. That means, 85% of photons go to waste when harvesting energy from sunlight. In fact, the theoretical limit of light harvesting in silicon-based solar panels is only 31% because of the low band gap of silicon, which only partially absorbs sunlight to form charge carriers in the device. To solve this problem, scientists have utilized three different crystals in a single PV cell to absorb more sunlight, and these studies have yielded a device efficiency of 37%. Just recently, scientists at the National Renewable Energy Laboratory (Golden, Colorado) and Boeing-Spectrolab have achieved a world-record conversion efficiency of 41% by using the same idea, establishing a new milestone in sunlight-to-electricity performance. Although such studies are very promising in this field, when it comes to production cost, these inorganic PV cells are still an expensive technology for power generation compared to fossil fuels.

Organic photovoltaics

An alternative solution to decrease the cost is to use devices with lower power efficiency but a very low cost of production. Organic-based PV materials offer such an alternative with easy and fast production techniques such as solution processing and printing. Conjugated polymers (polymers with alternating single and double bonds in their polymeric backbone) are especially important in this regard, since they exhibit semiconductor properties. The best organic PV cell efficiencies reported in recent years are around 5%. This number must double in order for the cells to be used in solar panels, assuming that the cell displays high photostability and conductivity. Many research groups are now focusing on organic-based solar systems as an alternative technology to their inorganic counterpart.

Although we are all familiar with solar energy, most of us do not know how electricity is produced from sunlight. To show the mechanism for photovoltaic activity, one first should look into an anatomy of a typical organic PV cell which is shown in Figure 1. This cell is based on an organic PV cell. The organic layer is sandwiched in between two electrodes where light absorption and charge separation occurs. Typically, glass is used for support but plastic materials can also be used as alternatives. The anode is usually indium tin oxide (ITO) and the cathode can be aluminum, calcium, gold, or magnesium. The electrodes must be semi-transparent to facilitate light absorption. Specifically designed conjugated polymers are utilized for sunlight absorption, where the wavelength range of absorbed light may vary from ultraviolet-visible to near infrared depending on the material used in the device. The efficiency of the device is determined by the extent of light absorption, efficiency of charge separation, and charge diffusion to the electrodes. The morphology of the organic layer has been found to be very important for device characteristics and cell efficiency. In an organic PV, an electron is promoted from the highest occupied molecular orbital (HOMO) level to the lowest unoccupied molecular orbital (LUMO) level upon light absorption (Figure 2). This transition results in an electron-hole pair which is then separated by the electric field formed by the different ionization energy of electrodes (Φ). Therefore, the electron moves to the cathode and the hole moves to the opposite side. This process causes charge flow between the electrodes and hence electricity is generated in the process.

Despite all the improvements in organic PV technology, current cell efficiencies are still low for electricity generation. The stability of organic PV materials must be improved as most of them are prone to degradation by oxygen and humidity in the air. The large-scale production of organic solar panels is possible, and yet the feasibility of current methods has not been investigated extensively so far.

Solar energy is a clean, renewable resource of energy and is projected to have significant role in the energy market in near future. Funding in the field of solar energy has been increasing in recent years due to the increasing need for energy and the likely reduction of fossil fuels towards the end of this century. Yet, our research efforts are still not sufficient for the advancement of this technology.

Importance of renewable energy for the environment: an Islamic perspective

Solar energy, like other renewable energy resources, is environmentally friendly. Its use should be promoted, as fossil fuels play a dominant role in the increase in greenhouse gases, which are believed to be responsible for the increased rate of global warming and hence climate change. Global warming may cause rises in sea level and changes in the amount and pattern of precipitation. These changes may in turn increase the frequency and intensity of extreme weather events, such as floods, droughts, heat waves, hurricanes, and tornados. Other consequences may include higher or lower agricultural yields, glacial retreat, reduced summer stream flows, and species extinctions. Warming is expected to affect the number and magnitude of the events mentioned above; however, it is difficult to connect particular occurrences to global warming.

In any case, focusing on renewable energy and energy-efficient technologies is one of the best options to secure the future of our planet and all existing forms of life on it. Our effort should not only be due to the expected shortage of fossil fuels in future. Rather, it must be seen as a duty and moral act to save the environment since use of renewable energy resources has little or no negative impact on nature. Religious awareness and guidance in this area is necessary so that each individual may take active part in the protection and development of the environment. Much environmental degradation is due to our ignorance of what our Creator requires of us. People should be educated to realize that the conservation of the environment is a religious duty demanded by God. This fact is expressed in Qur’an in a number of places such as, “Do good, even as God has done you good, and do not pursue corruption in the earth. Verily God does not love corrupters” (Qasas 28:77), “And do not follow the bidding of the excessive, who cause corruption in the earth and do not work good” (Shu’ara 26:151–152), “And do not cause corruption in the earth, when it has been set in order” (A’raf 7:56). Any deliberate damage to the natural environment and its resources is a kind of corruption which is forbidden by Islam.

As Muslims, we should protect and preserve the environment because by doing so we protect the creatures which pray to God and praise Him. Although we do not know how they praise God, the Qur’an clearly points this out: “The seven heavens and the earth, and all beings therein, declare His glory: There is not a thing but celebrates His praise, and yet you understand not how they declare His Glory!” (Isra 17:44). Islam is established on the concept of good (khayr). Since it is scientifically proven that protecting the environment is of great significance for all animals and plants on earth, Muslims should see it as khayr. In the last two verses of chapter Zalzalah (99:7–8), God says, “And whoever does good an atom’s weight will see it then. And whoever does ill an atom’s weight will see it then.”

Protecting God’s creatures and the environment is a duty of humankind because human beings are the “agents” of God on earth. This task cannot be performed by other creatures. Therefore, as the Muslim community we should all commit ourselves to the preservation and to the protection of the environment. Surely, investing in and promoting improvement of the technologies based on renewable energy is one way to go.

References

• http://www.nrel.gov/learning/re_basics.html
• http://www.islamonline.net
• http://lfw.pennnet.com/Articles/Article_Display.cfm?Section=ARTCL&ARTICLE_ID=257239&VERSION_NUM=3&p=12 (PHOTOVOLTAICS: Research targets more-efficient photovoltaics)
• http://lucy.mrs.org/publications/jmr/jmra/2005/dec/0407.html (Organic and nano-structured composite photovoltaics: An overview)
• http://www.orgchem.science.ru.nl/molmat/mm-web/education/caput-college/SolEnergMatCells-2004-83-125.pdf (A brief history of the development of organic and polymeric photovoltaics)
• http://en.wikipedia.org/wiki/Global_warming
• http://www.islamset.com/env/index.html

In recent years, we have realized that the world’s supplies of coal, gas and oil are limited. Nuclear power has been used as an alternative solution to fossil fuels. However, the use of nuclear power and fossil fuels incurred environmental problems so there is widespread public antipathy. As a result, the popularity of renewable energy has grown during the past twenty years. The World Energy Council estimated that renewable energy sources, such as solar, wind, hydro, wave and bio-mass, met 18% of the world’s energy needs in 1990 (World Energy Council, 1993). Their scenario is that the contribution from renewable energy could increase 30% by 2020.

One of the most promising of the renewable energy sources is the direct conversion of solar energy into electricity by photovoltaic generation. There are many reasons for growing popularity:

1. Photovoltaic generators do not pollute the air and do not leave waste products.

2. Photovoltaic generators are silent during operation.

3. They work effectively even in cloudy weather. They are more efficient at low temperatures.

4. As there are no moving parts, they work reliably for 20-30 years with little maintenance.

5. Solar energy is available everywhere so power can be generated anywhere it is needed. This makes photovoltaic generators attractive in the many places where there is no mains supply.

6. Photovoltaic generators can be planned and installed within a few months in contrast to conventional power stations which take at least five years to become operational.

7. Finally, photovoltaic generators can be located anywhere, such as in the roof or walls of an existing or already planned building, therefore they do no need to use up extra land.

The photovoltaic effect was first observed by Edmund Becquerel in 1839. Much later, in the 1930s, solid state researches developed the first photocells which were used in photographic exposure meters. In 1954, the Bell Telephone Laboratories made crystalline silicon solar cells with a conversion efficiency of 6% which was used in space programs. The market for photovoltaic modules has been growing steadily since; in 1991 it had reached about 50 MW per annum.

Solar Cell

The total radiant power from the sun falling on one square meter of a surface area can be as high as 1000W/m2 on a clear summer’s day and it can fall to 100W/m2 in cloudy conditions. In northern Europe, it seldom exceeds 850W/m2 (Treble F.C., 1993).

The inactive energy, solar energy, can be converted into electrical energy by solar cells. The absorption of light in semiconductors creates additional electrical charge carriers, both electrons and holes equally. If an electric field exists within the semiconductor, the negative electrons and positive holes move in opposite directions and this electrical charge separation results in the creation of a voltage. The movement of the electrical charges creates an electrical current and voltage so both current and voltage are generated simultaneously. This is the photovoltaic effect, the creation of a voltage by the action of light.

The basic way to establish an electric field in a semiconductor is to make a p-n junction. The electric field at the junction attracts electrons from the p-side and forces them to the n-side making it negatively charged. Similarly holes from the n-side are forced to the p-side, making this positively charged. Thus holes are creating a voltage. Figure 1 shows the basic features of a solar cell. The front contact grid is a thin metallic grid on the front surface and the back contact usually covers the whole of the back. This is called an n-on-p cell. Silicon is one of the popular semiconductor in the electronics industry so it is used for solar cells. Most commercial cells have a probable 20% efficiency which is the ratio of the maximum output power to the input power from the sun, but over 25% efficiency has been achieved in the laboratory. The theoretical limit for crystalline silicon cells is about 30% under 1000W/m2 irradiance and 25 °C operating temperature (Hill B., 1995). Solar cells which were made from gallium arsenate have achieved 34.2% efficiency.

Solar cells are fine objects which must be protected from any possible damage. The cells are usually connected in series, in parallel or a combination of both in order to produce necessary power and voltage. A photovoltaic module which is a collection of solar cells was bought about US$4/Wp (US$ per peak watt) in 1995. Modules must be capable of reliable operation for many years. The current target is a lifetimes of 30 years.

Photovoltaic applications

In 1994 the total world sales of photovoltaic modules reached 70 MWp per year. In recent years, photovoltaic modules have found many applications in various sectors. The main applications are given below:

1. Space applications: solar cells were first used to produce electricity for satellites in 1958. Since then, photovoltaic power generation has become an essential energy source in space. Solar cells can operate near or far from sun.

2. Telecommunication: transmitters and repeater stations are often located in distant places such us mountains, islands or deserts. Solar power has proved the cheapest and most reliable power for transmitters and repeater stations.

3. Electricity in villages: the majority of the population of the developing countries, approximately two billion people, live in small villages without electricity. As almost developing countries will find extending the mains grid to a few customers far removed from the mains supply lines too expensive, photovoltaic systems are the obvious, cheaper alternative. A small photovoltaic module with a battery can provide enough power for basic lighting, TV and a small refrigerator for a house. By 1993 more than 10,000 home systems had been installed in Indonesia. In addition, solar home systems had been installed in the Philippines, the Dominican Republic, Columbia, India, Kenya, Mexico, Morocco, Sri Lanka and Zimbabwe by 1993. The average price of a 50 Wp solar home system was about US$500 in 1993. Assume that a 50 Wp solar house system in future will cost about US$250, then 400 million solar home systems will be

installed in the world. The other applications of solar modules in villages are water pumping, irrigation, water purification, street lighting and TV receivers (Lysen E.H., 1994).

4. Grid connected buildings: the solar modules can be fixed on roofs or walls so no additional land is required. The most sensible use of photovoltaic cladding would be on commercial buildings because they need energy during working hours rather than at night. Photovoltaic cladding presently costs about 800m-2 in comparison with marble cladding cost around 1000m-2, granite cladding 800m-2. Photovoltaic cladding gives high-tech images for office blocks at lower cost than marble.

5. Central power stations: photovoltaic power stations have, so far, only been installed for purposes of research. Today, Austria, Germany, Italy, Spain and USA have small stations of this type.

The other applications of photovoltaic systems are pocket calculators, watches, clocks, torches, garden lights, portable radios, battery chargers for boats, caravans, electric cars, toys, railway signals, traffic warning lights, alarm systems, automatic weather stations, military equipment and so on.

Conclusion

The photovoltaic system cannot at present compete with mains electricity. However, early in the next century, when economies of scale are expected to bring about a reduction in manufacturing costs, solar power will be an important energy source.

References

• World Energy Council (1993) Energy for Tomorrow’s World, Kogan Page /St. Martin’s Press.
• Treble F. C. (1993) Solar Energy, The Solar Energy Society, Birmingham.
• Hill B. (1995) ‘Solar Power’, IEE Power Engineering Journal, (August 1995), pp. 175-80. Lysen E.H. (1994) ‘Photovolts for villages’, IEEE Spectrum, 31, (10), pp.34-9.

Daylighting is becoming more popular in commercial buildings and manufacturing facilities in the United States. After Thomas Edison invented the electric light, most architects changed their building plans and designed for more and more artificial lighting. As a result, only a very small percentage of the light used in major buildings and facilities came directly from the sun. Recently, the Europeans have realized the importance of daylighting and begun to use a reasonable percentage of sunlight in their buildings. The Rocky Mountain Institute, Snow-mass, Colorado, has investigated the benefits of daylighting and reported that daylighting increased productivity and reduced absenteeism by 15 percent. Also, sunlight reduces the heating and cooling bill.

In 1993, Wal-Mart Stores Inc. opened a prototype store in Lawrence, Kansas, with nine special skylights designed by Andersen Corp., Bayport, Minnesota. The architectural firm of Leo A. Daly, Omaha, Nebraska, opened an office building in 1983 with l5ft high window walls and a glazed roof. About 50% of its electricity bill for lighting was saved as a result (Reno Gazette-Journal, November 27, 1995). Daylighting is an inexpensive way of lighting interiors since the sun is a ‘free’ light source which can be further exploited by installing skylights on the roof. On an overcast day, the light entering through a 2 sq. ft skylight area is equivalent to three 100-watt light bulbs.

There are two additional reasons for installing skylights. First, the cooling load of a building can be reduced by using daylight. The reason for this is that whereas about 80% of the power of an electric light is converted to heat, sunlight has a far lower heat content and therefore requires far less air-conditioning. Second, just at the time when there is the heaviest demand for electricity (and other utilities) from manufacturing facilities, namely during the summer, sunlight is at its most plentiful and available: in short, skylights can significantly reduce peak load stresses and costs.

An illumination level of 50 footcandles (540 Lux) at the work site is the design standard in industrial facilities. A large portion of this illumination level comes from electric lights of fluorescent and incandescent lamps. Almost 5% of electricity consumption in the US is used up to provide adequate illumination in commercial and industrial buildings.

In production facilities generally, there is a lack of awareness about the energy conservation potential of skylights. Some manufacturers are so unaware about the cost savings that can be achieved by daylighting that they do not have skylights in their production areas, and leave lamps on in work areas throughout daylight hours. In other places which do have them, skylights have been neglected to the extent that they are so dirty they block the incoming sunlight.

Since heating and cooling load are increased with increased skylight surface area, there is a limitation associated with this measure. Some authorities have suggested that the optimum skylight surface area should be reckoned at between 2 and 4% of roof surface area. However, since the measure depends upon local climate conditions, the range should be allowed to vary between 2 and 10%. In many potential sites, heating only (and not cooling) is the principal consideration. Generally, therefore, building designers with heating costs in mind tend to prefer 2% for cold climates and 10% for warm climates.

Heating load and costs will increase when skylights are installed. However, the increase in heating cost is considerably smaller than the saving from reduced lighting cost. The average unit cost of electricity is three times greater than that of natural gas (typically preferred for heating). In any case, heat loss from the skylights can be minimized by double glazing them. In view of the favourable financial balance and the productivity improvements to be expected from daylight working, the benefits from installing skylights generally offset any negative consequences of doing so.

The amount of savings in electric lighting consumption and costs depends on climate and operating periods. The payback period for installing skylights ranges from one to five years. They can be an expensive roof aperture, but it is relevant to note that the lifetime of a skylight is more than twenty years. The skylights need to be cleaned at least once annually, which means that service and maintenance costs are negligible. Skylights are most cost- effective in uninsulated ceilings in climates, like that of southern California, which have no heating season. In such climates, the workplace roof is typically covered with corrugated metal sheets making skylights both easy and cheap to install: corrugated fibreglass sheets can be cut and fitted in place of the metal sheets wherever the skylights are required.

References 

• MURDOCH, B. J. (1985) Illumination Engineering: From Edison’s Lamp to the Laser, Macmillan Publishing Company, New York.
• NUTFER, D. W., BRITTON A. J. and HEFFINGTON W. M. (1993) ‘Conserve Energy to Cut Operating Costs’, Chemical Engineering, September, pp.126-37.
• PIERSON, J. (1995) ‘Natural light gets warm welcome’, Reno Gazette-Journal, November 27, pp.2ff. 

O believers, when you stand for prayer, wash your faces, and your hands up to the elbows, and wipe your heads, and wash your feet up to the ankles. If you are unclean, bathe and purify your bodies fully. But if you are ill or in the middle of travelling or … you cannot find water, then take wholesome dust and wipe your faces and hands with that. For Allah does not wish to burden you, rather He desires to purify you and to complete His blessing and favour upon you so that, perhaps, you may he grateful.[5:6]

Here is a grand prescription from among the many marvels of the Qur’an. The day will come when even non-Muslims will imitate the Muslim wudu or washing before prayer, a privilege and favour Muslims have enjoyed for more than fourteen hundred years. And they have done so, more or less, unawares, as it is only through the discoveries of biologists in the last twenty years that we have come to understand fully the wonderful effects of wudu. The three principal benefits that human health derives from washing are related to the circulatory system, the immune system, and the electrostatic balance of the body.

a) The circulatory system

The circulatory system is twofold. First, the heart pumps blood out to the tissue cells in every part of the body. Second, it collects back the biologically used blood. If this reverse circulation in particular is disturbed, diastolic blood pressure increases and ageing, even the onset of death, may be precipitated.

The healthful condition and functioning of the blood vessels is essential to this twofold circulatory system. Blood vessels resemble flexible tubing, dividing into thinner branches as the distance from the heart increases. If the thinner tubes in particular become hardened and lose their elasticity, pressure and workload upon the heart are increased. This is known in medical jargon as arteriosclerosis.

Various aspects of our lives cause the blood vessels to harden and become constricted. This problem, considered to be the basis of ageing and bodily deterioration, is now a distinct field of medicine on its own. Improper nutrition and nervous reactions can have a serious effect on the condition of the blood vessels. If sclerotic development is observed in a blood vessel, what practical measure can be taken against it?

The hardening and narrowing of blood vessels does not happen all at once, but over a long period. The vessels furthest from the heart, such as those in the brain, feet and hands, are more vulnerable to the process which begins slowly in these locations and goes on continuously with the passage of time. However, there is an application in our daily routine which, in a sense exercises blood vessels by alternately contracting and dilating them. Its agent is water, which gives rise to temperature gradients. Water ensures flexibility and visor of vessels distant from the heart by dilating them when hot and contracting them when cold. It also forces nutrients, deposited in tissues as a result of sluggish circulation, back into the bloodstream by virtue of the temperature difference.

In view of these facts, is it possible to understand the verse commanding Muslims to wash the hands, feet and face in the wudu rite as anything short of a marvel, particularly in the light of the conclusion of the verse: He desires to…. complete His blessing and favour upon you. Circulation of the blood is a favour to us from the Creator. The command to do wudu completes that favour by maintaining the blood vessels and the circulatory system generally in a healthy state. This is the first of the many blessings of wudu. It is impossible to deny the fact that washing protects against senility which is the way the hardening of blood vessels reflects on the circulation in the brain of a person who has been doing wudu regularly since childhood.

b) The immune system (lymphatic circulation)

In addition to the circulation of red blood cells in the body, there is also the circulation of white blood cells or leucocytes. The vessels of this system are ten times thinner than those which conduct red blood cells. We sometimes see its colourless fluid oozing from the skin walls in some abrasions or wounds. It is this lymphatic circulation which keeps all points of the body within the protection of the immune system. Any bacterium, alien object, or cancer cell (the cause of which is not known), which may have invaded the body is destroyed by the warrior cells or leucocytes in the lymphatic circulation. The appearance of an infectious disease or cancer in the body is always contingent on the malfunctioning of the immune system.

Exactly how this system of vessels expands and contracts has not yet been fully clarified. It is known, however, that heat and cold influence the system. Catching an infectious disease such as a common cold is ascribed to the inability, due to contraction of these vessels, to dispatch leucocytes in sufficient numbers to the afflicted area. Now the proper functioning of this system and its thin vessels, like that of the circulatory system in general, is closely linked with the invigorating effect of washing. The structure of the immune system, which provides resistance against all diseases, is reinforced through the wudu, and the divine favour mentioned in the verse is realized.

Now someone might claim that, while the lymphatic system is indeed invigorated by washing, it is just a coincidental and unintended side effect. However, the precise form of the command to do wudu disposes of this incorrect claim. I would argue, on the contrary, that the way in which the wudu is commanded to be done specifically aims at the lymphatic system as well. The reasons are as follows:

1. For the lymphatic system to function properly, even a single point in the body must not he neglected, which is assured by the full ablution or ghusl.

2. The most important centre for stimulating the lymphatic system is the nasopharyngeal region behind the nose and tonsils, and washing these spots is especially enjoined.

3. Stimulation of both sides of the neck has great influence on the lymphatic system, and this is also present in the wudu.

The most formidable warrior cells of the body, the lymphocytes, are transported to the farthest reaches of the body and, after passing through intensive biological training, patrol each point in the body many times a day. If they meet a bacterium or a cancer cell, they destroy it. Is this not a divine blessing of the first quality? If a circulatory disorder occurs once in a while and you are able to avert or mitigate its effect by means of regular wudu, is it not proper to regard the command as the promised fulfilment of divine favour for which mankind are required to give thanks?

c) Static electricity

The body normally has a balance of static electricity, and the physiology of a healthy body is closely related to this electrostatic balance.

Atmospheric conditions, as well as plastic clothing and products common in our time can adversely affect this balance. Painful illnesses, irritability and facial wrinkles are the best-known results. Most of us have become aware of this electricity when climbing out of a car or after sitting in a plastic chair. Stormy weather has a comparable effect. Healing by acupuncture and, in certain respects, physiotherapy, can redress this imbalance of static electricity; but we can avoid the effect entirely, simply by doing the wudu several times a day.

There are many psychosomatic illnesses arising from electrostatic imbalance. I shall not dwell on these here. I shall address only the question of skin care, which has become such a fashionable subject now.

The worst influence of static electricity is exerted continually on the small subcutaneous muscles (under the skin), finally rendering them inoperative, which is why wrinkles set in, starting with the face, though the skin is affected over the whole body. At this point, many of my readers will have divined at least one of the reasons for the radiant appearance of those who have done wudu all their lives. Whoever maintains the habit of regular washing inevitably has the more healthy, and therefore the more beautiful, skin. How remarkable it is that in our time, when millions are spent on cosmetics, a tenfold increase in expenditure would still not properly substitute for simple washing.

Doubtless, the sceptic will ask, but does wudu really have anything to do with static electricity?

Of course it does. The part of the verse pertaining to tayyamum when water is not available for wudu, underlines the fact. For this substitute for wudu also disposes of static electricity to a significant extent. Indeed, the importance of it has hitherto gone unrecognized, and no-one has tried to explain why, tayyamum can take the place of wudu when the necessity arises.

As the verse clearly states, the sanitary aspect of wudu is a great blessing which we can now partially explain in medical terms. A person might well say: But I already wash my face and hands anyway. Let us recall, however, that as a widespread public habit, this practice has a very short history (barely seventy years or so) even amongst nations who have a tendency to claim to be the most civilized in the world. More important, cleanliness based on a sort of general good advice can never be sustained with the steadiness of discipline which, in Islam, it has by virtue of its association with worship.

To be sure, the worth and significance of wudu does not end with these medical observations the sense of well-being and dignity derived from wudu also contribute to the general health of the practising Muslim but here my aim has been to make widely known precisely those additional medical benefits.