Monday, 14 October 2013

As It Is Climate Scientists Call Decrease of Arctic Ice ‘Unprecedented’

From VOA Learning English this is As It Is.

Welcome back! I’m Caty Weaver. The United Nations and the World Meteorological Organization created the Intergovernmental Panel on Climate Change in 1988. The panel is a committee made up of hundreds of scientists. Last week, an IPCC working group released a report about climatic conditions around the world. Today, we will tell you what it says.                      
                             
And later we visit India where shrinking glaciers and melting Himalayan snow could affect millions of people below.

Scientists are surer than ever before that the Earth is warming and that human activity is to blame. That is the message of the new report from the Intergovernmental Panel on Climate Change. As we hear from Christopher Cruise, the report’s findings will help inform policy makers and the public as they consider action to fight climate change.  

One-hundred-ten governments approved this scientific agreement:

“It is extremely likely that human influence has been the dominant cause of observed warming since the mid-20th century.” 

The head of the World Meteorological Organization, Michael Jarraud, spoke at a press conference about the new report.

“It should serve as yet another wake-up call that our activities today will have a profound impact on society, not only for us, but for many generations to come.”

Greenland and Antarctic ice sheets have been losing mass and glaciers continue to shrink, the report says. It calls the decrease of Artic sea ice, “unprecedented,” meaning nothing like this has been noted before. The report also examines the mean rate of sea level rise. It says that since the middle of the 19th century, the rate is higher than at any time in the past 2000 years.

The working group also examined the connection between extreme weather events and climate. Brenda Ekwurzel is a climate scientist with the Union of Concerned Scientists, a non-profit group. She has worked with the scientists who prepared the IPCC report.

“The most we can say is that extreme events dealing with coastal flooding and extreme heat, (we have) very, very high confidence with these events being highly linked to climate change.”

She says the report blames human activity for half of the increased warming over the past fifty or so years. One such activity is the burning of fossil fuels in factories, buildings and cars. This produces heat-trapping gasses.

Past IPCC reports have led the way to international agreements like the 1997 Kyoto Protocol. It ended in 2012. The United Nation’s top climate official, Christiana Figueres, says the new report will help move new climate talks forward.

The Intergovernmental Panel on Climate Change is sometimes criticized as appearing to be too conservative in its predictions. But, Ms. Figueres says this report is right on the mark.

Everything that we thought we knew about climate change has been underestimated, that we will have much faster and much more intense effects from the growing concentration of greenhouse gases in the atmosphere. So, it’s a very sobering message that calls for a more invigorated and more accelerated policy response to address that.”

Government leaders and climate experts will get a chance to do that at the climate negotiations next month. The talks will take place in the Polish capital, Warsaw.

I’m Christopher Cruise.

You are listening to As It Is from VOA Learning English.

Now we go to the northern Indian state Himachal Pradesh to look at the effects of rising temperatures right now. The town of Manali is in the Kullu Valley. It is economically dependent on the thousands of people who travel up the Himalaya Mountains every year to escape the heat of the Indian plains.

D.S. Aditya is manager of Sterling Resorts in Manali. He says many people like to visit a snow-covered pass that lies about 50 kilometers up one mountain.

Wherever you go like there’s one destination, this is famous. If you visited Manali, Rohtang is main attraction. Because of the snow.”

The Rohtang Pass has many more visitors now than it did 10 years ago, thanks partly to the growing financial success of India’s middle class. In summer months, more than two thousand vehicles crowd the narrow mountain road.

Ravi Thakur of Himalayan Caravan Adventure has lived in Manali since he was a child.

Twenty years ago, we could count how many cars are here in Manali. Now, if you come in season time, we do have traffic jam for four, five, six kilometers on the Rohtang Road.”

Visitors enjoy the beauty of the pass. But environmentalists are warning about the increasing traffic on mountains and glaciers.

J.C. Kuniyal is a scientist at the GB Pant Institute of Himalayan Environment and Development. He is studying temperature changes in the Rohtang area. He says temperatures in the Kullu Valley have risen be about six-tenths of a degree Celsius. That is about the same as the average increase worldwide.

But, what worries him is the effects of uncontrolled tourism on the mountain ecosystem.

“I have seen that the regions which are facing a high influx due to floating population or human activity, there aerosols are increasing. These are supposed to be the main causes to melt the Himalayan glaciers.”

The aerosol gases come both from diesel-powered vehicles and burning of wood for cooking by local people. The smoke leaves thick black ash on the glaciers. This causes them to absorb, or take in, more heat.

Local people are witnessing the effects of climate change and human activity on glaciers. Ravi Thakur has been walking the mountains since childhood. He says he has seen a loss of mountain snow and glacial ice.

“We keep going every year, almost to the same routes, and I have seen that glaciers, they are receding. In 15 years I have seen that big change.”

That has raised concerns. The area’s local glaciers are the headwaters for rivers like the Indus and the Ganges. The two rivers are the source of fresh water for millions of people in South Asia.

Pradipto Ghosh is a director at the Energy and Resources Institute in New Delhi.

If the present trend of gradual loss of net glacial mass continues, then over time the flow from the glaciers would reduce.”

Scientists say there is serious concern about water for agriculture on the Indian plains. Arun Shrestha is a climate change specialist at the International Center for Integrated Mountain Development in Nepal.

Those communities, their agricultural system relies quite heavily on melt water.”

Some people, like mountain guide Ravi Thakur, worry about possible changes in the future.

Till I leave my life, we won’t be facing those scarcity of water, but later on, the coming generation, they will have problems.”
             
Environmentalists will continue trying to establish how deep those problems might become.

Wednesday, 2 October 2013

Which drink makes you more creative?

When this happens, normally I grab a coffee to help get the ideas flowing, but for the last few days in Montreal, no one’s been allowed to drink the water due to a bacteria leakage, which also means, no coffee.
So instead, I grabbed the next best thing to help me get going – a beer.
This got me wondering about coffee and beer and which one would actually help me be more creative and get work done. Hopefully, this will help you decide when it’s best to have that triple shot espresso or ice cold brew.

What is creativity really?

From a scientific perspective, creativity is your ability to think of something original from connections made between pre-existing ideas in your brain.
These connections are controlled by chemicals called neurotransmitters. One of these neurotransmitters is adenosine, which alerts your brain when you’re running out of energy and reacts by slowing down the connections made between neurons by binding to adenosine receptors.
Adenosine is kind of like your brain’s battery status monitor. Once your energy levels get low, adenosine starts to slow your brain functioning down.
This is why after a few hours of intense work, you begin to feel tired, like your brain has run out of juice.
The only way to recharge it is to take a break; unless, you’ve got a secret weapon handy.

Your brain on coffee

Every coffee drinker is familiar with the feelings after drinking a fresh cup of java.
I know after I’ve had a latte or espresso, I feel more focused.
If I’m having a conversation with someone, words seem to flow without pauses, ums, or ahs.
If I’m writing, my fingers never stop typing.
This happens because caffeine blocks adenosine receptors, preventing adenosine from binding to it’s receptors and tricking your brain into thinking you have lots of energy.
Here’s a comic illustration of what caffeine does when it makes it to your brain:
adenosine
This effect happens within just 5 minutes of drinking your coffee.
When adenosine receptors are blocked, chemicals that increase the performance of your neural activity, like glucose, dopamine, and glutamate, are allowed to work overtime.
So while you may feel that coffee is giving you more energy, it’s simply telling your body that your energy reserves are good to go even when they’re long gone.

Coffee is like a bottle rocket

The peak effect of caffeine on your body happens between 15 minutes and 2 hours after you consume it.
When caffeine from your coffee enters your bloodstream, you become more alert from an increase in the production of the hormones adrenaline and cortisol.
The problem is, if this over-stimulation of adrenaline and cortisol occurs too regularly, your adrenal glands, which absorb adrenaline to help make you feel energized, gradually begin to require more adrenaline to give you the same ‘pick-me-up’ feeling as before.
When researchers at Johns Hopkins University looked at low to moderate coffee drinkers (as little as one 14-ounce mug per day), they found that even this little amount of coffee can cause your body to develop a tolerance to caffeine and require more of it to get the same stimulation.
Just like the thrill of lighting a bottle rocket and watching it explode all within a few seconds, the good feelings associated with coffee are short-lived and pretty soon you need another hit to feel good again.

Why there are lots of famous drunk artists, but no famous drunk accountants

While caffeine pulls a number on your brain to make you feel like you have more energy, alcohol has it’s own way of influencing your creativity.
After you’ve had a couple beers, drinking makes you less focused because it decreases your working memory, and you begin to care less about what’s happening around you. But as researchers at the University of Chicago discovered, this can be a good thing for creativity’s sake.
The researchers devised a game where 40 men were given three words and told to come up with a fourth that could make a two-word combination with all three words.
For example, the word “pit” works with “arm”, “peach”, and “tar”:
study-1
Half of the men drank two pints of beer before playing the game while the other half drank nothing. The results showed that men who drank, solved 40 percent more of the problems than sober men.
It was concluded that a blood alcohol level of 0.07 (about 2 drinks) made the participants better at creative problem-solving tasks but not necessarily working memory tasks where they had to pay attention to things happening in their surroundings (like driving a car).
By reducing your ability to pay attention to the world around you, alcohol frees up your brain to think more creatively.
It looks like author Ernest Hemingway was on to something when he said:
When you work hard all day with your head and know you must work again the next day what else can change your ideas and make them run on a different plane like whisky?

Alcohol produces better ideas

In an interesting study on the topic of alcohol and its effects on creativity, author Dave Birss brought together a group of 18 advertising creative directors and split them into two teams based on their amount of career experience.
One team was allowed to drink as much alcohol as they wanted while the other team had to stay sober.
The groups were given a brief and had to come up with as many ideas as they could in three hours. These ideas were then graded by a collection of top creative directors.
The result? The team of drinkers not only produced the most ideas but also came up with four of the top five best ideas.
While alcohol may not be the drink of choice when you need to be alert and focused on what’s going on around you, it seems that a couple drinks can be helpful when you need to come up with new ideas.

A creative prescription: The optimal way to drink coffee and beer

Both coffee and beer (in moderation) have shown to be helpful when you’re working on certain types of tasks, however, you shouldn’t drink either when you need to do detail-oriented or analytical projects like your finances.
The increase in adrenaline from caffeine and inhibition of your working memory from alcohol will make you more prone to make mistakes.

Beer for the idea

The best time to have a beer (or two) would be when you’re searching for an initial idea. Because alcohol helps decrease your working memory (making you feel relaxed and less worried about what’s going on around you), you’ll have more brain power dedicated to making deeper connections.
Neuroscientists have studied the “eureka moment” and found that in order to produce moments of insight, you need to feel relaxed so front brain thinking (obvious connections) can move to the back of the brain (where unique, lateral connections are made) and activate the anterior superior temporal gyrus, a small spot above your right ear responsible for moments of insight:
eureka-moment
Researchers found that about 5 seconds before you have a ‘eureka moment’ there is a large increase in alpha waves that activates the anterior superior temporal gyrus.
These alpha waves are associated with relaxation which explains why you often get ideas while you’re going for a walk, in the shower, or on the toilet.
Alcohol is a substance that relaxes you so it produces a similar effect on alpha waves and helping us reach creative insights.
Coffee meanwhile, doesn’t necessarily help you access more creative parts of your brain like a couple pints of beer.

Coffee for the execution

If you’ve already got an idea or an outline of where you want to go with your project, a cup of coffee would do wonders compared to having a beer to execute on your idea.
The general consensus across caffeine studies is that it can increase quality and performance if the task you are doing seems easy to you and doesn’t require too much abstract thinking.
In other words, after you have an initial idea or a plan laid out, a cup of coffee can help you execute and follow through on your concept faster without compromising quality.
This graphic pretty much sums up when you should drink coffee:
coffeeaddict
Quick tip: If you drink coffee, do so before noon so it doesn’t effect your sleep. On average, it will take between 5-10 hours for the caffeine from a cup of coffee to be removed from your system and messing up your sleep cycle can have a negative impact on your creative output for days to come.

Always in moderation

If you decide to drink coffee and beer while you’re working, you should stick to no more than 2 cups of coffee or a couple beers per sitting and try to do this no more than once or twice per week.
Coffee and beer shouldn’t be thought of as magic bullets for creativity.
They are ways to create chemical changes that occur naturally in your brain with a healthy lifestyle. Quality sleep patterns and allowing yourself to take breaks by splitting your day into sprints will do the same trick.
But, if you have to choose between coffee or beer, think about what type of task you are about to do and make sure you don’t over-drink.
Too much of either and you’ll lose the benefits of both.

Monday, 30 September 2013

Researchers Identify Immune Cells That Promote Growth of Beta Cells in Type 1 Diabetes

Joslin researchers have identified immune cells that promote growth of beta cells in type 1 diabetes. This study provides further evidence of a changed role for immune cells in type 1 diabetes pathology. [Video]
The study was published online Sept. 27 and will appear in the January issue of Diabetes.
"In type 1 diabetes, the immune system infiltrates pancreatic islets and destroys insulin-producing beta cells. While infiltrating immune cells are traditionally considered to negatively impact beta cells, recent studies in non-obese diabetic (NOD) mice have suggested that immune cells can also contribute to preserving beta cells," says lead author Dr. Ercument Dirice, research fellow in the Kulkarni Lab in the Section on Islet Cell and Regenerative Biology at Joslin Diabetes Center .
This finding is strengthened by the observation by Joslin researchers who reported that members of the Center’s 50-Year Medalist Study, who have lived with type 1 diabetes for 50 years or more, retain some beta cells and produce insulin.
"The traditional view of type 1 diabetes was that immune cells killed all beta cells and people with the disease would have to take insulin for life. But we know that some beta cells do survive and secrete insulin even when the patients have had type 1 diabetes for 50 years," says senior author Dr. Rohit N. Kulkarni, Associate Professor of Medicine at Harvard Medical School and the principle investigator of the project at Joslin. In this study,
Joslin researchers were interested in learning exactly how immune cells could promote beta cell growth and identifying the type of cell and the mechanisms underlying this effect.
In a series of experiments, the researchers injected NOD mice with immune cells from the pancreatic islets of donor NOD mice and assessed their effects on beta cells. The immune cells tested included subtypes of B or T immune cells.
Dirice, the lead author of the study, found that it is T cells not B cells that are associated with beta cell proliferation. Mice that received B cells showed no difference in beta cell growth. Mice that received the T cell subtypes CD4+ and CD8+ showed an elevation in all markers of beta cell proliferation compared to mice that did not receive them. The researchers also found that beta cell growth happens after islets are infiltrated by immune cells and is independent of the effects of glucose and insulin.
Further experiments with cell cultures showed that CD4+ and CD8+ cells secrete inflammatory cytokines and chemokines (Interleukin 2, Interleukin 6, Interleukin 10, MIP-1α and RANTES), which together enhanced beta cell proliferation. This is the first study to report that this group of "soluble factors" is involved in promoting beta cell growth.
"This gives us new insights into what is happening in the pathology of type 1 diabetes. The immune cells we identified send signals which appear to protect and promote growth of beta cells. This opens up an exciting new area that scientists have thought about; now we have the hard data to substantiate it," says Dr. Kulkarni.
The next step is to investigate the effects of immune cells on human beta cell growth. The factors secreted from CD4+ and CD8+ cells are potential therapeutic candidates to enhance beta cell growth to prevent or delay the onset of type 1 diabetes.
"We need to learn more about the relationship of beta cell death and proliferation to determine if we can harness these soluble substances to encourage beta cell proliferation rather than destruction," says Dr. Kulkarni.

Nanoparticle Vaccine May Offer Protection Against Many Infectious Diseases

Many viruses and bacteria infect humans through mucosal surfaces, such as those in the lungs, gastrointestinal tract and reproductive tract. To help fight these pathogens, scientists are working on vaccines that can establish a front line of defence at mucosal surfaces.
Vaccines can be delivered to the lungs via an aerosol spray, but the lungs often clear away the vaccine before it can provoke an immune response. To overcome that, MIT engineers have developed a new type of nanoparticle that protects the vaccine long enough to generate a strong immune response — not only in the lungs, but also in mucosal surfaces far from the vaccination site, such as the gastrointestinal and reproductive tracts.
Such vaccines could help protect against influenza and other respiratory viruses, or prevent sexually transmitted diseases such as HIV, herpes simplex virus and human papilloma virus, says Darrell Irvine, an MIT professor of materials science and engineering and biological engineering and the leader of the research team. He is also exploring use of the particles to deliver cancer vaccines.
“This is a good example of a project where the same technology can be applied in cancer and in infectious disease. It’s a platform technology to deliver a vaccine of interest,” says Irvine, who is a member of MIT’s Koch Institute for Integrative Cancer Research and the Ragon Institute of Massachusetts General Hospital, MIT and Harvard University.
Irvine and colleagues describe the nanoparticle vaccine in the Sept. 25 issue of Science Translational Medicine. Lead authors of the paper are recent PhD recipient Adrienne Li and former MIT postdoc James Moon.

Sturdier vaccines

Only a handful of mucosal vaccines have been approved for human use; the best-known example is the Sabin polio vaccine, which is given orally and absorbed in the digestive tract. There is also a flu vaccine delivered by nasal spray, and mucosal vaccines against cholera, rotavirus and typhoid fever.
To create better ways of delivering such vaccines, Irvine and his colleagues built upon a nanoparticle they developed two years ago. The protein fragments that make up the vaccine are encased in a sphere made of several layers of lipids that are chemically “stapled” to one another, making the particles more durable inside the body.
“It’s like going from a soap bubble to a rubber tire. You have something that’s chemically much more resistant to disassembly,” Irvine says.
Cryoelectron microscope image of the nanoparticles developed by MIT researchers to deliver vaccines to mucosal surfaces. Image: Adrienne Li and Dong Soo Yun
Cryoelectron microscope image of the nanoparticles developed by MIT researchers to deliver vaccines to mucosal surfaces. Image: Adrienne Li and Dong Soo Yun
This allows the particles to resist disintegration once they reach the lungs. With this sturdier packaging, the protein vaccine remains in the lungs long enough for immune cells lining the surface of the lungs to grab them and deliver them to T cells. Activating T cells is a critical step for the immune system to form a memory of the vaccine particles so it will be primed to respond again during an infection.

Stopping the spread of infection

In studies of mice, the researchers found that HIV or cancer antigens encapsulated in nanoparticles were taken up by immune cells much more successfully than vaccine delivered to the lungs or under the skin without being trapped in nanoparticles.
HIV does not infect mice, so to test the immune response generated by the vaccines, the researchers infected the mice with a version of the vaccinia virus that was engineered to produce the HIV protein delivered by the vaccine.
Mice vaccinated with nanoparticles were able to quickly contain the virus and prevent it from escaping the lungs. Vaccinia virus usually spreads to the ovaries soon after infection, but the researchers found that the vaccinia virus in the ovaries of mice vaccinated with nanoparticles was undetectable, while substantial viral concentrations were found in mice that received other forms of the vaccine.
Mice that received the nanoparticle vaccine lost a small amount of weight after infection but then fully recovered, whereas the viral challenge was 100 percent lethal to mice who received the non-nanoparticle vaccine.
“Giving the vaccine at the mucosal surface in the nanocapsule form allowed us to completely block that systemic infection,” Irvine says.
The researchers also found a strong memory T cell presence at distant mucosal surfaces, including in the digestive and reproductive tracts. “An important caveat is that although immunity at distant mucus membranes following vaccination at one mucosal surface has been seen in humans as well, it’s still being worked out whether the patterns seen in mice are fully reproduced in humans,” Irvine says. “It might be that it’s a different mucosal surface that gets stimulated from the lungs or from oral delivery in humans.”
Melissa Herbst-Kralovetz, an assistant professor of basic medical sciences at the University of Arizona College of Medicine, says the nanoparticles are “an exciting and effective strategy for inducing effector-memory T-cell responses to nonreplicating subunit vaccines through mucosal vaccination.”
“More research will need to be conducted to determine the delivery approach to be used in humans, but this vaccination strategy is particularly important for diseases that may require significant T cell-mediated protection, such as HIV,” says Herbst-Kralovetz, who was not part of the research team.

Tumour defence

The particles also hold promise for delivering cancer vaccines, which stimulate the body’s own immune system to destroy tumours.
To test this, the researchers first implanted the mice with melanoma tumors that were engineered to express ovalbumin, a protein found in egg whites. Three days later, they vaccinated the mice with ovalbumin. They found that mice given the nanoparticle form of the vaccine completely rejected the tumours, while mice given the uncoated vaccine did not.
Further studies need to be done with more challenging tumour models, Irvine says. In the future, tests with vaccines targeted to proteins expressed by cancer cells would be necessary.
The research was funded by the National Cancer Institute, the Ragon Institute, the Bill and Melinda Gates Foundation, the U.S. Department of Defense and the National Institutes of Health.
The nanoparticle technology has been patented and licensed to a company called Vedantra, which is now developing infectious-disease and cancer vaccines.

Friday, 20 September 2013

10 Most Beautiful Waterfalls in the World

01 Angel Falls, Venezuela
Angel Falls, Venezuela the highest Waterfalls in the World, American aviator Jimmie Angel, who, while flying over Venezuela
Angel Falls — Venezuela, Photo — Link
The first on our list is a waterfall Angel – the highest in the world. His height – 979 meters, which is 15 times greater than the height of the famous Niagara Falls. The waterfall is in Venezuela, in Canaima National Park, and every year thousands of tourists come into the country specifically to see this wonder of nature with his own eyes, and BASE jumpers are risky even jump with it. The waterfall is named after American aviator Jimmie Angel, who, while flying over Venezuela, observed from a height of this waterfall and discovered it around the world.

02 Iguazu Falls, Brazil

Iguazu waterfall, but a whole system of 275 waterfalls in height from 60 to 80 meters and a length of about 3 kilometers. The largest waterfall – it’s a natural formation in the shape of U, called the Spanish conquistadors’ throat the devil
Iguazu Falls — Brazil, Photo — Link

This waterfall, located on the border of Brazil and Argentina, is considered one of the most powerful in the world. In fact, Iguazu – it’s not a waterfall, but a whole system of 275 waterfalls in height from 60 to 80 meters and a length of about 3 kilometers. The largest waterfall – it’s a natural formation in the shape of U, called the Spanish conquistadors’ throat the devil. ”
03 Waterfalls Plitvice Lakes, Croatia
Waterfalls Plitvice Lakes, Croatia, the national park are varied colors, from bright blue to dark blue, depending on the types of microorganisms that are found in them. Several waterfalls, connecting the lake, look at the background of green and blue waters of the surrounding forest was amazing.
Waterfalls Plitvice Lakes — Croatia, Photo — Link

These amazingly beautiful waterfalls are located in Croatia, Plitvice Lakes National Park. Lake of the national park are varied colors, from bright blue to dark blue, depending on the types of microorganisms that are found in them. Several waterfalls, connecting the lake, look at the background of green and blue waters of the surrounding forest was amazing.

04 Niagara Falls, USA
Niagara Falls, USA, Niagara Falls in the north-eastern United States. He is also one of the most powerful in the world – about 2.8 million liters of water per second, just think! Tourists like to Niagara Falls because it is relatively easy to access and view from all sides.
Niagara Falls — USA, Photo — Link

Of course, it was impossible to ignore one of the most famous waterfalls in the world – Niagara Falls in the north-eastern United States. He is also one of the most powerful in the world – about 2.8 million liters of water per second, just think! Tourists like to Niagara Falls because it is relatively easy to access and view from all sides.

05 Victoria Falls, Zimbabwe
Victoria Falls, Zimbabwe is, of course, the Victoria Falls. His height – 108 meters, power – one million liters per second, and fans are really thrills can take a long jump from the waterfall on the rubber stretch.
Victoria Falls —Zimbabwe, Photo — Link

Another famous and very beautiful waterfall in Zimbabwe – is, of course, the Victoria Falls. His height – 108 meters, power – one million liters per second, and fans are really thrills can take a long jump from the waterfall on the rubber stretch.

06 Falls of Yosemite, USA
Falls of Yosemite, USA in California in the same national park. Yosemite – one of the highest waterfalls in the world – 739 meters. Interestingly, the waterfall in winter almost “calms down” and in the spring and summer reaches its maximum amplitude.
Falls of Yosemite — USA, Photo — Link

This waterfall can be seen in California in the same national park. Yosemite – one of the highest waterfalls in the world – 739 meters. Interestingly, the waterfall in winter almost “calms down” and in the spring and summer reaches its maximum amplitude.

07 Kaieteur Falls, Guyana
Kaieteur Falls, Guyana a country in South America. Kaieteur – one of the largest waterfalls in the world. His height – about 226 meters. For a long time about this waterfall, known only to locals, but in 1870 he accidentally discovered by English geologist. To get to the waterfall is quite difficult, but it does not stop the flow of tourists wanting to see Kaieteur own eyes.
Kaieteur Falls — Guyana, Photo — Link

This marvel of nature hidden in the tropical forests of Guyana, a country in South America. Kaieteur – one of the largest waterfalls in the world. His height – about 226 meters. For a long time about this waterfall, known only to locals, but in 1870 he accidentally discovered by English geologist. To get to the waterfall is quite difficult, but it does not stop the flow of tourists wanting to see Kaieteur own eyes.

08 Gallfoss Falls, Iceland
Gallfoss Falls, Iceland waterfalls located in the tropics – there are those that are located far to the north, for example, an amazing waterfall Gallfoss Icelandic in Iceland, a country that is famous for its natural wonders. Gallfoss – one of the most powerful waterfall in Europe, although his height – only about 30 meters.
Gallfoss Falls — Iceland, Photo — Link

Not all of the beautiful waterfalls located in the tropics – there are those that are located far to the north, for example, an amazing waterfall Gallfoss Icelandic in Iceland, a country that is famous for its natural wonders. Gallfoss – one of the most powerful waterfall in Europe, although his height – only about 30 meters.

09 Waterfall Dettifoss, Iceland
Waterfall Dettifoss, Iceland, – Dettifoss, the most powerful in Europe. His height – 40 meters, and power – about 200 cubic meters of water per second. The waterfall is surrounded by beautiful cliffs, gorges and lakes and is very popular both among locals and tourists.
Waterfall Dettifoss — Iceland, Photo — Link

Another Icelandic waterfall – Dettifoss, the most powerful in Europe. His height – 40 meters, and power – about 200 cubic meters of water per second. The waterfall is surrounded by beautiful cliffs, gorges and lakes and is very popular both among locals and tourists.

10 Sutherland Falls, New Zealand
Sutherland Falls, New Zealand the South Island and is considered one of the most beautiful and mysterious waterfalls in the world. To get to the waterfall is not easy, but it’s worth – a narrow water jet, flying at an elevation of 580 meters, surrounded by thick foliage and rocks is a fantastic sight
Sutherland Falls — New Zealand, Photo — Link

In New Zealand there is a waterfall called Sutherland. It is located on the South Island and is considered one of the most beautiful and mysterious waterfalls in the world. To get to the waterfall is not easy, but it’s worth – a narrow water jet, flying at an elevation of 580 meters, surrounded by thick foliage and rocks is a fantastic sight!

Tuesday, 27 August 2013

The Next Google: It's Like Google, But For Search

It is no longer appropriate for search to be under the thumb of private industry. It's a critical part of the national infrastructure. So if I were a real pinko, I'd be advocating for the nationalization of Google, à la Chavez—but I'm not a real pinko. Besides, the American people have already bought and paid for an ideal alternative to Google. That's right: we have the means in hand to create a public, ad-free, totally fair and reasonably transparent search engine with a legal mandate to operate in the public interest, and most of the work is already done. We have also a huge staff of engineers to conclude what little remains on the development and deployment side.
Who are these American heroes, soon to be accepting the thanks of a grateful nation? Why, our fellow citizens, the software engineers and tech gurus and endless numbers of contractors of the NSA! Why don't they make themselves useful and stop spying on everyone and instead, use all that computing power and archived information to make us a fair, fast, ad-free search engine?
They have a copy of the whole Internet, soon to be housed in their giant bunker in Utah!
It is already, apparently, equipped with the latest in search technology! It's probably already better than Google.
Others make their case against Google on antitrust laws. It's not illegal to have a monopoly. According to U.S. courts, it's just not your fault that everybody loves your product! What's illegal is using that power to do bad things, like suppress your own competition. This is why there are ongoing government investigations into Google's anti-competitive business practices in the U.S., in Canada and in Europe.
Probes like these have so far tended to focus on Google's preferential treatment of its own services over those of its competitors in Google search results. Which amounts to ignoring the elephant in the room: Google, with its 67% share of U.S. search traffic (sounds low, tbh), has a potential influence far beyond the industries in which it operates formally. At the moment, Google can legally use its power to make or break any business, or any politician, publication, or public figure it chooses, for any old reason it wants, provided that reason doesn't fall foul of antitrust laws.
For instance, let's suppose one of Google co-founder Sergey Brin's friends were to open a new cafe in Mountain View: there is no legal proscription whatsoever against Google's vaulting the Friends o' Brin Cafe to the top of results on searches for "best cafe Mountain View." Or even "best cafe."
A close reading of Google's ten "Core Principles" appears to suggest, but not quite guarantee, that Google won't simply grant preferential treatment at its own discretion. The fact is, however, that it's entirely up to them. Given the understandably secret nature of Google's algorithms and other techniques for determining search results, it would be impossible to say whether or not this is in fact already happening.
Already companies live or die at the hands of Google. Any update to the Google Panda search ranking algorithm has rippling effects through the Internet. One thing that seems to be the case: older sites, with thousands of internal links and a deep history on the Internet, seem to be constantly downgraded. That's bad news for some non-spam media companies that in part live off search traffic. Google results, in general, overweight newness. It is becoming more and more impossible to find relevant results older than three months.
As well, Google will tell you that active engagement with their product Google+ will be "beneficial" to any publisher as a whole, including in search. Publishers now ignore Google+ at their peril, whether it is relevant to their business or not.
But let's take the real case of 23andMe.com, the "privately-held personal genetics company" whose CEO, Anne Wojcicki, is married to Sergey Brin. According to recent SEC filings, Google invested approximately $1.5 million in the company's Series D round, and Google leases office space to the company. Here's the current results for a search on the phrase "genetic testing":

Friday, 9 August 2013

முல்லா குட்டி கதைகள் !

ஒரு தடவை அறவொழுக்கத்தை நேசிக்கும் பிரபலமான தத்துவவாதி ஒருவர் முல்லா வசிக்கும் ஊரை கடந்து செல்ல வேண்டியிருந்தது. அப்போது சாப்பாட்டு நேரமாகையால் அவர் முல்லாவிடம் நல்ல உணவு விடுதி எங்குள்ளது என்று கேட்டார். முல்லா அதற்கு பதில் சொன்னவுடன், தத்துவவாதி போகும் போது பேச ஆள் கிடைத்தால் நல்லது என்ற எண்ணத்தில் முல்லாவையும் தன்னுடன் சாப்பிட வருமாறு அழைத்தார்.
முல்லாவும் நெகிழ்ந்து போய் அந்த படிப்பாளியை அருகிலிருந்த உணவு விடுதிக்கு அழைத்துச் சென்றார். அங்கே போன பிறகு ‘அன்றைய ஸ்பெசல் அயிட்டம் என்ன?’ என்று கடைச் சிப்பந்தியிடம் கேட்டார் முல்லா. ‘மீன்! புதிய மீன்!’ என்று பதில் சொன்னார் சிப்பந்தி. ‘இரண்டு துண்டுகள் நல்லதாக கொண்டு வாருங்கள்’ என இருவரும் ஆர்டர் செய்தனர்.
சிறிது நேரம் கழித்து ஹோட்டல் சிப்பந்தி ஒரு பெரிய தட்டில் இரு மீன் துண்டுகளை வைத்துக் கொண்டு வந்தார். அதில் ஒரு துண்டு பெரியதாகவும், இன்னொரு துண்டு சிறியதாகவும் இருந்தது. அதைக் கண்டவுடன் முல்லா எந்தவொரு தயக்கமில்லாமல் பெரிய மீன் துண்டை எடுத்து தனது தட்டில் போட்டுக் கொண்டார். முல்லாவின் செய்கையால் கடுப்படைந்து போன தத்துவவாதி முல்லாவைப் பார்த்து கடுமையாக முறைத்து விட்டு, ‘முல்லா நீங்கள் நடந்து கொண்ட முறையானது எந்த தர்ம, நீதி, நியாய, மத சாஸ்திரத்துக்கும் ஒத்துவராத ஒன்றாகும்’ என்றார்.
முல்லா, தத்துவவாதி சொல்லுவதையெல்லாம் மிக அமைதியுடன் பொறுமையாக கேட்டுக் கொண்டு வந்தார். கடைசியாக அந்த மெத்தப் படித்தவர் பேசி முடித்தவுடன், “நீங்களாக இருந்தால் என்ன செய்திருப்பீர்கள்?” என்றார் முல்லா. “நான் மனச்சாட்சியுள்ள மனிதனாகையால் சிறு மீன் துண்டை எடுத்திருப்பேன்”. ‘அப்படியா, ரொம்ப நல்லது. இந்தாருங்கள் உங்கள் பங்கு’ என்று சொல்லி சின்ன மீன் துண்டை அந்த தத்துவவாதி தட்டில் வைத்தார் முல்லா.

Tuesday, 6 August 2013

Blood test to tells U REALLY need antibiotics

A simple three-minute blood test could tell GPs whether a patient needs antibiotics.
Not only could this help avoid patients suffering nasty side-effects from taking unnecessary drugs, but it could also tackle one of the greatest threats to modern health — antibiotic resistance. The test tells a doctor whether the patient is suffering from a viral or a bacterial infection — that way, they know whether or not to prescribe antibiotics.
Antibiotics are only effective against bacteria — they do not kill viruses. Currently, the type of infection can only be confirmed with a blood test which must analysed in a lab, a process that can take two to three days.
However, GPs say they often give antibiotics as a fail-safe measure, and that patients pressure them for the pills.
According to Public Health England (formerly the Health Protection Agency), if patients ask their GP for an antibiotic, the vast majority will get one.
Over-prescribing has consequences for both the patient and the population. As well as causing side-effects, over-use can lead to bacteria becoming resistant, making antibiotics less effective at fighting infections. The Government’s chief medical officer has described this as one of the greatest threats to modern health.
Over the past five years alone, the number of antibiotic prescriptions has risen by 10 per cent to 41  million prescriptions at a cost of £170 million to the NHS, and a third of all Britons have taken them in the past 12 months.
But now a simple fingerstick test could solve this ‘catastrophic threat’. The test — which involves taking a drop of blood from the finger — can tell doctors within three minutes whether an illness is caused by a bacterial infection which requires antibiotics, or a virus, which does not.
It measures a substance called C-Reactive Protein (CRP) in the blood. The amount of this protein increases when the body is fighting a bacterial infection, but not when it is fighting a virus, which triggers a different immune response.

So a doctor would know that if the CRP level was shown to be low, antibiotics would not be required.
Studies show that providing ‘proof’ that they are unnecessary to patients who demand antibiotics can significantly reduce the number of prescriptions.
One EU-funded study, presented at the World Association of Family Doctors conference in 2010, looked at how respiratory infections which are generally caused by viruses were treated by 600 GPs in six different countries. It found that antibiotic prescriptions fell by 25 per cent when doctors used the CRP test.
British experts say the test could be a useful tool for significantly reducing antibiotic prescriptions.
Dr Nick Francis, a senior clinical research fellow at Cardiff University and expert in antibiotic resistance in primary care, says: ‘Unfortunately, it is very difficult to accurately determine whether an infection is viral or bacterial.

‘Markers such as CRP have evolved to help where there is lingering uncertainty after a clinical assessment or where the patient has strong beliefs that antibiotics are needed.’
However, not everyone needs the test. ‘Patients who appear very unwell should be treated with antibiotics or admitted to hospital without the test because they could develop complications,’ explains Dr Francis.
‘But for those patients where there is doubt, or where the GP feels antibiotics are not needed but the patient is putting pressure on to prescribe them, the test can be helpful.’
The test is currently only available in laboratories in the UK (it can be carried out privately for around £50) because the NHS does not yet fund it in GP practices (the machine to analyse the test would initially cost £1,000 and then £3 per test).
Sid Dajani, a community pharmacist in Southampton and spokesman for the Royal Pharmaceutical Society, says it is likely to be some time before the test is routinely available on the NHS.
‘CRP testing would be a natural extension to the clinical services we offer but it will be two or three years before there is enough evidence for it to be made widely available.’
Other concerns about the test are that the results are not always clear — levels of CRP also increase as a result of inflammation caused by other conditions such as rheumatoid arthritis as well as infections.
Dr Francis explains: ‘The test is only a guide. It does not tell you categorically that this patient has a bacterial infection and this patient does not. It gives you a number that has to be interpreted in light of the other symptoms and the patient’s overall risk profile.
‘For example, you are more likely to treat an elderly person with diabetes with antibiotics than a young healthy person, as the elderly person is more likely to develop complications.’
Experts say the best way to reduce antibiotic prescriptions is to educate doctors and patients about common complaints and when antibiotics are necessary.
Mr Dajani warns: ‘To see this test as the panacea is an extremely dangerous idea. We need to work hard to educate patients about when it is appropriate to take antibiotics and make sure they take them correctly and finish the course.’
Public Health England adds: ‘CRP may be useful in a small range of infections provided the test is robustly quality controlled.
‘But nothing can replace taking a detailed patient history and thorough examination.’

Tuesday, 30 July 2013

Breastfeeding 'can enhance a child's IQ'

The apparent decision by the Duchess of Cambridge to breastfeed has been given a boost by fresh evidence showing it can help raise a baby’s IQ.
The longer the child is breastfed – ideally exclusively – the higher the intelligence scores are at the age of seven.
The study also found breastfeeding can enhance language skills from the age of three.
The US researchers recommend babies are solely fed on breast milk for the first six months and are given the chance to breastfeed until a year old.
However, British experts warned that delaying the introduction of solid foods until six months at the earliest might leave some babies feeling hungry.
It emerged yesterday that the Duchess has at least one maternity dress made for breastfeeding and was given encouragement in hospital to help her baby George start on her milk.
Earlier research has shown breast milk protects babies against stomach bugs, chest infections, asthma and allergies, and confers health advantages in later life.
But only a small number of women in the UK breastfeed their babies for long periods and the number of new mothers starting in 2011 fell slightly to 73.9 per cent.
Barely 2 per cent of babies are breastfed exclusively for six months.
'It's all mum's fault for not breastfeeding me'
The latest study included 1,312 mothers and children who had taken part in Project Viva, a long-term investigation of pregnancy and child health in the US.
It found seven-year-olds breastfed for the first year of life were likely to score four points more in a test of verbal IQ than bottle-fed children.
Verbal intelligence scores at seven increased by 0.35 points for every extra month of breastfeeding.
Three-year-olds also benefited, having higher scores in a language-acquisition test the longer they had been breastfed. Exclusive breastfeeding had the greatest effect.
The US team of researchers reported the findings in the journal JAMA Pediatrics.
The scientists, led by Dr Mandy Belfort, from Boston Children’s Hospital, said: ‘Our results support a causal relationship of breastfeeding in infancy with receptive language at age three and with verbal and non-verbal IQ at school age.
'These findings support national and international recommendations to promote exclusive breastfeeding through age six months and continuation of breastfeeding through at least age one year.'
A number of factors that might have influenced the results, including home environment and mothers' IQ, were accounted for by the researchers.
Children took part in several tests, including the Peabody Picture Vocabulary Test at age three and the Kaufman Brief Intelligence Test at age seven.
Certain nutrients in breast milk may benefit the developing infant brain, it has been suggested.
One of these is docosahexaenoic (DHA), which is abundant in fish.
Part of the research looked at whether mothers' fish consumption was linked to the benefits of breastfeeding but the results were not statistically significant.
It is thought that chemicals naturally present in breast milk can aid brain development, but skin to skin contact and bonding during breastfeeding may also play a part.
But Clare Byam Cook, an independent breastfeeding counsellor and former midwife, said: ‘It’s best to keep an open mind about what your baby’s individual needs are.
'Many babies feel hungry if they only get breast milk and most need solids before six months.’
She said mothers who can breastfeed their babies easily are giving them a great start in life.
She said: 'Most women who give up find it too difficult to continue.
'They are not unaware of the benefits to the baby, they have been brainwashed into thinking if they don't their baby will miss out and it can be a very worrying time.
Ms Cook, the author of Top Tips For Breast Feeding and Top Tips For Bottle Feeding, said there was new evidence that breastfeeding exclusively for six months may not be best for baby, putting them at risk of allergies, food aversion and even obesity.
Babies can be safely given solid foods at least eight weeks earlier in life than official Department of Health guidelines telling women to breastfeed exclusively for the first six months, according to researchers.


Alcohol and the sexes: Men tend to drink when they're angry, while women feel more depressed after a night out

A person's gender affects when they drink and how they feel the morning-after-night-before, according to new research.
A study has found that men tend to drink when they feel angry and women experience more depressive emotions the day after drinking.
Scientists found that alcohol was consistently ineffective at drowning sorrows however.

Valerie Harder, assistant professor of psychiatry at the University of Vermont and lead author of the study, said ‘These male-female differences are consistent with several reports showing that men and women respond differently to stress, and experience mood and substance use disorders at different rates.'
To understand people's moods and drinking habits, Professor Harder and her colleagues used an interactive voice-recording program like the ones found in call centres.
 
The 246 study participants, aged between 21 and 82, were problem drinkers who had been flagged by their primary-care doctor.
The suspected alcoholics then went through an alcohol treatment program and were called in every day for six months and reported their moods, stress level and drinking habits on the program.
The results revealed that for men, it was anger that fuelled drinking.
According to the study, a man who felt angry was more likely to drink the next day than a man who did not feel angry.
Man angry
depressed woman
The study found that men were more likely to turn to drink if they were angry. Women on the other hand were found to become far more depressive after drinking a large quantity of alcohol
Professor Harder said: 'Working on strategies for male drinkers to manage their anger may warrant special emphasis in alcohol treatment approaches [in the future].
'Furthermore, results from a recent study of relapse after alcohol use treatment suggest that targeting the relationship between [negative emotions such as anger] and alcohol use
could decrease the probability of relapse, thus improving alcohol treatment outcomes.'
Happiness and sadness were also recorded in the study.
While researchers found that neither emotion acted as a particular trigger for drinking in one gender over the other, they did discover that they did surface after drinking.
Professor Harder and her colleagues presumed that people would report less anger and sadness after drinking, and more happiness a day after drinking. But the data showed the exact opposite.
Both men and women reported feeling less happy the day after drinking, but the effect was much stronger for women.
The researchers said the findings could play an important role in developing new treatment approaches toward alcoholism and relapse prevention.
Professor Harder said the findings could be useful in the doctor's office and at home - people who feel alcohol improves their mood may want to pay attention to how they feel the day after drinking.
And rather than simply asking about the number of drinks a person has in a week, doctors could also ask patients about their moods before and after their drinking.

Survey finds smokers feed their children less, buy them smaller birthday presents and raid their money box to fund their habit

The dangers of smoking during pregnancy or near a child have been well-documented, but new research has found that that smoker parents are also less caring towards their children.
A survey has discovered that nicotine addict mothers and fathers cut back on Christmas presents for their children, buy them less clothing and even feed them less to fund their daily cigarette habit.
The poll, which examined the lifestyle behaviour of smokers, also discovered that some people stole from friends, applied for credit cards and even asked strangers on the street for money when desperate for their fix.
The dangers of smoking during pregnancy or near a child has been well-documented but new research has shown that smoker parents are less caring towards their children
The dangers of smoking during pregnancy or near a child has been well-documented but new research has shown that smoker parents are less caring towards their children. Some even admitted to feeding their children less to ensure they always had cigarettes
The research was carried out by pharmaceutical company Pfizer as part of their Don't Go Cold Turkey Campaign and asked 6,271 smokers about how they funded smoking in tougher economic times.
It revealed that while 60 per cent of smokers refused to pay more than £8 for a packet of cigarettes, one per cent - which equated to 31 people - were willing to pay an astonishing £40.

The most alarming statistics related to smoking parents however. It found that many were often more willing to reduce their child's quality of life than go without cigarettes.
A shocking 20 per cent admitted to having bought their children fewer or cheaper clothes and shoes  to save money instead of quitting smoking.
Victims: A poll found that children with parents who smoke were more likely to have smaller Christmas presents.
Victims: A poll found that children with parents who smoke were more likely to have smaller Christmas presents. It also revealed that nicotine addict mothers and father often raided their children's money box to fund their habit
A worrying 17 per cent admitted to cutting back on food and drink for their children, 35 per cent reduced the amount of treats they gave them and 20 per cent said they even cut back on Christmas and birthday presents to continue smoking.
Nearly nine per cent - which equated to 350 of those polled - had stolen money from their child's money box.
Around 70 per cent of people who still smoke say they want to quit
Around 70 per cent of people who still smoke say they want to quit
Just under 13 per cent said they had stopped taking their children to after school groups, 17 per cent admitted to having cut back on toy purchases and just under seven per cent had even refused to send their children on school trips to save money rather than quit their habit.
Almost 65 per cent of those polled admitted to feeling under financial pressure and 50 per cent said they were concerned about falling into debt but all still continued to feed their tobacco habit.
And a significant number of smokers admitted to engaging in reckless and even dishonest behaviour to fund the habit.
Nearly 1,000 people had dipped into their life savings to make sure they could afford cigarettes and 275 had even stolen from friends of family members.
Nearly seven per cent had applied for a credit card for the sole purpose of purchasing cigarettes, 11 per cent had gone without food and nearly 100 people admitted to having asked a stranger for money.
Some people even said they turned their heating off and instead wore several jumpers to cut their heating bills and ensure they could afford a packet of cigarettes.
Dr Sarah Jarvis, who is involved in the Pfizer campaign said: 'Most smokers are fully aware of the financial burden that a smoking habit can have on their lives but the vast majority are not taking advantage of the free help available to them from their healthcare professional.
'Smoking is extremely addictive, and while 70 per cent of people who still smoke say they want to quit, the average number of times a smoker has tried to quit before succeeding is four. 
Unfortunately, only three per cent of people who try to go ‘cold turkey’ without any help from a health care professional are still smoke free after one year.'

Monday, 29 July 2013

5 Classic Mistakes in Macro Photography?

Delving into macro photography opens up a fascinating, sometimes strange, new world. The ultra-close up views of flowers, plants, insects, and even otherwise unremarkable household items reveal a novel perspective, a depth of existence that people are usually quite unaware of. Most of us already dislike (hate) spiders, but their creepiness factor multiplies exponentially when viewed at life size magnification through a macro lens. Thanks, macro lenses.
 
I think it’s safe to say that we all enjoy and appreciate macro photography to varying degrees; staring into a spider’s eight cold, distant eyes may not be your thing, but it’s captivating nonetheless. Perhaps you prefer the delicateness of a tulip or the texture of a leaf. Regardless of the subject, it is one’s appreciation of a good macro shot that inspires them to try their hand at it.

cradle by jDevaun, on Flickr
 
The problem is, there’s a significant learning curve for macro photography and many people find it to be a frustrating venture at first. Even once you’ve progressed a little bit, you might find that your shots still lack a certain something, something that you feel is keeping your macro photography from really standing out.

Requiem by jDevaun, on Flickr
If this describes you at all, have a look over the following checklist of mistakes to avoid when doing macro photography.

  1. Not Getting Down to Your Subject’s Level – Perspective matters. Just like you would crouch down to take a portrait of a child, you should also shoot your macro subjects from their level. This, of course, means that you might end up on the ground; you’ve got to get right in there and share space with whatever you’re shooting. The working distance (the distance between the front of the lens and the subject) of the lens you’re using will dictate exactly how close to your subject you need to be, but by shooting at your subject’s level — as opposed to shooting down on it — you’re using visual perspective to increase the interestingness of the photo.
  2. Neglecting Composition – Novice macro shooters sometimes feel that composition can afford to take a back seat. Not true. It’s undeniably cool to see such small subjects so close up and in such great detail. Again, even ordinary objects can appear extraordinary through a macro lens. But that doesn’t mean you can sacrifice interesting composition just because you’ve captured the amazing details of a bumblebee. Sure, the view of the bumblebee may be great, but is the photograph itself any good? The answer to that lies not so much in what the subject is, but more in how it’s presented.
  3. Failure to Stabilize – Camera shake can be a real concern with macro photography. For those who have never attempted macro photography, think of some of the issues that come into play when shooting with a telephoto lens, namely the fact that the more your focal length increases, the more you have to account for camera shake. Even with lenses that feature built-in stabilization you need to practice good technique in order to get sharp images. A large part of good macro photography technique involves using a tripod. Of course, this doesn’t apply if you’re shooting moving subjects such as insects, in which case you’ll want to use flash to freeze their movement. Otherwise, a tripod is your best bet for mitigating the challenges of working with a macro lens.
  4. Missing Focus – Missing focus can happen anytime, anywhere, while doing any kind of photography, but focusing becomes increasingly difficult when shallow depth of field and high magnification are introduced to the equation. In macro photography, you can’t really rely on autofocus to get it right all the time; nothing is more frustrating than thinking you focused on the right part of your subject then, after viewing the image, realizing you got it all wrong. This is one genre of photography in which manual focus should be the first thing on your mind; precision is of utmost importance here and manual focus put you in total control, allowing you to adjust your point of focus without having to readjust your composition.
  5. Underestimating the Importance of Light - Given that light is absolutely necessary for photography of any kind, this may seem rather obvious. But new macro photographers might fail at first to understand that much more light than usual is required for macro work. This is due, in large part, to how close the lens needs to be to the subject; you always run the risk of the lens blocking out the light, whether natural light or on-camera flash (which isn’t typically recommended for macro work). Not only do you have to consider how much light you’re getting, you should also take into consideration the quality of light. Just as with portraiture, you want to avoid harsh shadows and flat lighting. The general principles of portrait lighting and how to soften it also apply to macro lighting.
 
The above mistakes are some of the most common culprits of bad macro photographs and we’ve all made them. So, don’t wallow in frustration; as with all mistakes, if you learn from them and correct them — and get plenty of practice — the end result will be everything you want it to be. Keep shooting.