Using less effort to think, opinions lean more conservative

(PhysOrg.com) -- When people use low-effort thought, they are more likely to endorse conservative ideology, according to psychologist Scott Eidelman of the University of Arkansas. Results of research by Eidelman and colleagues were published online in Personality and Social Psychology Bulletin.

“People endorse conservative ideology more when they have to give a first or fast response,” Eidelman said. “This low-effort thinking seems to favor political conservatism, suggesting that it may be our default ideology. To be clear, we are not saying that conservatives think lightly.”

While ideology – either conservative or liberal – is a product of a variety of influences, including goals, values and personal experiences, Eidelman said, “Our data suggest that when people have no particular goal in mind, their initial cognitive response seems to be conservative.”

Eidelman collaborated with Christian Crandall of the University of Kansas; Jeffrey A. Goodman of University of Wisconsin, Eau Claire; and John C. Blanchar, a University of Arkansas graduate student, on studies reported in “Low-Effort Thought Promotes Political Conservatism.”

The researchers examined the effect of low-effort thought on the expression of ideology in several situations. In a field study, bar patrons were asked their opinions about several social issues before blowing into a Breathalyzer. Whether the individual self-identified as liberal or conservative, higher blood alcohol levels were associated with endorsement of more conservative positions. The results indicated that this was not because the conservatives drank more than the liberals.

The results were not just the alcohol talking: In one lab experiment, some participants were asked to respond quickly to political ideas, while others had ample time to respond. In another, some participants were able to concentrate while responding to political statements, while others were distracted. In both cases, participants with less opportunity to deliberate endorsed conservative ideas more than those who were able to concentrate.

In a fourth study, deliberation was manipulated directly. Some participants gave their “first, immediate response” to political terms, while others gave “a careful, thoughtful response.” Those instructed to think in a cursory manner were more likely to endorse conservative terms, such as authority, tradition and private property, than those who had time to reflect.

The researchers stressed that their results should not be interpreted to suggest that conservatives are not thoughtful.

“Everyone uses low-effort thinking, and this may have ideological consequences,” they write. “Motivational factors are crucial determinants of ideology, aiding or correcting initial responses depending on one’s goals, beliefs and values. Our perspective suggests that these initial and uncorrected responses lean conservative.”

More information: http://psp.sagepub … stract?rss=1

Provided by University of Arkansas

"Using less effort to think, opinions lean more conservative." April 5th, 2012. http://www.physorg.com/news/2012-04-effort-opinions.html

Posted by
Robert Karl Stonjek

Study shows income inequality a key factor in high US teen births

New research reveals the surprising economics behind the high U.S. teen birth rates, and why Texas teens are giving birth at triple the rate of Massachusetts youth: high income inequality and low opportunity cost.

For the first time, Wellesley College economist Phillip B. Levine and University of Maryland economist Melissa Schettini Kearney conducted a large-scale empirical investigation to study the role that income inequality plays in determining early, non-marital childbearing. Using econometric analysis of large-scale data sets, Levine and Kearney discovered that variation in inequality across the United States and other developed countries can account for a sizable share of the stunning geographic variation in teen childbearing. They found that teens of low socioeconomic status were more likely to give birth if they lived in a state with high income inequality. Moving from a low inequality state to a high inequality state increased their rate of teen childbearing by 5 percentage points.

According to Levine, who teaches economics analyses of social policies as Katharine Coman and A. Barton Hepburn Professor of Economics at Wellesley College, it's long been argued that a sense of hopelessness and despair is closely related to higher rates of teen pregnancy. Levine explained, "If a young woman sees little chance of improving her life by investing in her education and career skills, or by marriage, she is more likely to choose the security, immediate gratification and happiness of parenthood. Our work captures this idea in a standard economics model of decision-making."

Levine and Kearney derive a formal economic model that incorporates the perception of economic success as a key factor driving one's decision to have an early, non-marital birth. Their findings show that for poor women living in locations of high inequality, limited opportunity reduces the opportunity cost of early, non-marital childbearing and thereby increases its occurrence.

While the U.S teen birth is the highest in the developed world (more than triple the rates in Spain, Japan, and Sweden), the national rate has declined since its 1991 peak. Levine and Kearney investigated possible factors behind these trends. The data showed that expanded access to family services through Medicaid and reduced welfare benefits had statistically relevant impact on the lowered rates. However, these factors accounted for only 12% of the teen birth rate decline. Furthermore, Levine and Kearney found that abstinence only or mandatory sex education had no impact on teen birth rates. The researchers determined that factors typically claimed to impact teen pregnancy actually explain very little of the recent trend and call for further investigation.

Levine and Kearney conclude that teen childbearing is so high in the U.S. because of underlying social and economic problems. In other words, teenage childbearing is a symptom, not a cause of poverty.

The findings bear important implications for U.S. policymakers. According to Levine, who has closely studied the economics of social policies, the high rate of teen childbearing in the United States matters because it is a marker of a social problem, rather than the social problem itself. "If the problem is perceived lack of economic opportunity, then policy interventions need to attack that. Access to early childhood education programs and college financial aid, for instance, have proven to be successful in improving the earnings—and sense of hope—of participants. Our findings show that these programs may also have the added benefit of lowering teen pregnancy rates. Giving teens a sense of opportunity and hope may be much a more powerful prescription than abstinence-only, sex education, or birth control combined."

More information: The research, co-authored by Phillip B. Levine and Melissa Schettini Kierney, is published by the National Bureau of Economic Research (NBER) and available online:

"Why is the Teen Birth Rate in the United States so High and Why Does it Matter?" 
Melissa Schettini Kearney, Phillip B. Levine 
http://www.nber.or … apers/w17965

"Explaining Recent Trends in the U.S. Teen Birth Rate" 
Melissa Schettini Kearney, Phillip B. Levine 
http://www.nber.or … apers/w17964

"Income Inequality and Early Non-Marital Childbearing: An Economic Exploration of the "Culture of Despair" 
Melissa Schettini Kearney, Phillip B. Levine 
http://www.nber.or … apers/w17157

Provided by Wellesley College

"Study shows income inequality a key factor in high US teen births." April 5th, 2012. http://www.physorg.com/news/2012-04-income-inequality-key-factor-high.html

Posted by
Robert Karl Stonjek

Idaya Kovil - Shirdi Sai Baba Tamil Song by Bombay Jayashri

Nokia Lumia 900 Review: Bigger Is Not Always Better

The sequel to the best Windows Phone we've ever used is...not the best Windows Phone we've ever used

By Dan Nosowitz

Lumia 900 and iPhone The Lumia is the bigger one. Dan Nosowitz

If you want to buy a phone right now, and you're shopping based on quality rather than price, you have two choices in terms of size. You can get the iPhone, with its 3.5-inch screen, or you can choose from a handful of top-tier Android and Windows phones, all of which will have, at the bare minimum, a four-inch screen. Most of them will be bigger--4.3 inches is much more common right now, and an increasing number are even larger, including the Samsung Galaxy Nexus(4.65 in), HTC Titan (4.7 in), and the Samsung Galaxy Note (which, at 5.3 inches, is more lunchtray than phone).

The Nokia Lumia 900 is essentially a 4.3-inch version of the Lumia 800, a phone I absolutely loved in its 3.7-inch iteration (a Europe-only model). So reviewing the Lumia 900 presents an interesting question: with most other specs remaining constant, how does the experience of using a phone change when it grows to the size most phone manufacturers insist we really want?

WHAT'S NEW

The Lumia 900 is Nokia's first "flagship" Windows Phone that's available in North America (the Lumia 710, a cheapie, has been available on T-Mobile for a little while already). It's the sequel to the much-admired Lumia 800 and its changes are mostly in size (of various sorts). It's got a 4.3-inch screen, compared to the Lumia 800's 3.7-inch screen; it has 4G LTE (on AT&T), compared to the Lumia 800's 3G; it has a bigger battery and a front-facing camera.

Nokia Lumia 900 and Plaid Sheets:  Dan Nosowitz

WHAT'S GOOD

This is mostly a good phone. Windows Phone is a great operating system; it's still maturing, but it's very usable, and it's an interesting and distinctly different approach to a smartphone than iOS or Android. (More on that here.) The physical design is pretty good; it's inoffensive, at worst, and is weighty enough to feel sturdy rather than cheap and plasticky, as many Windows Phones do (especially those made by Samsung). It's also nicely thin, only a millimeter or two thicker than the iPhone. The screen, though not thrilling in its resolution, has great deep blacks, which is important when using an OS with a predominantly black interface by default.

AT&T'S 4G LTE continues to be great. This is the first phone using AT&T's LTE I've personally used, and it feels just as screamingly fast as Verizon's. It's startling how quickly things load--LTE is as fast or faster than many people's home internet connections, so apps download instantly, web pages load instantly, music and podcasts sync instantly. I was impressed with AT&T's coverage too--I used the Lumia 900 all over New York City and it never dropped out on me. And the giant 1830mAh battery will get you through a full day with normal use, which is not always the case with the current crop of LTE-capable phones.

WHAT'S BAD

Bigger is not better. Gadget makers will tell you I'm wrong--they'll point to sales numbers, saying that people have embraced big phones by the millions. But you could just as easily point to the iPhone, the most successful phone line in the country by a long shot, and say that it proves that people love smaller phones. Or you could remember that if you want a good Android or Windows phone, you are basically forced to buy a giant one. There are no longer any top-tier 3.7-inch phones. There are a rapidly decreasing number of 4-inch phones (the Motorola Droid 4, an above-average but not particularly special phone, is the only high-end 4-incher released in the past six months). If you're shopping Android or Windows, your choices are limited to big or bigger. And that's not necessarily for the better.

Most gadgets need to be of a particular size to fulfill their particular roles. A phone has to fit in your pocket or purse. An ebook reader has to display a page of text. A tablet has to provide a full web experience. You can't just stretch it out, like it's a Gumby made of silicon and glass and metal and plastic, and say it's a better device because of it. And that's exactly what the Lumia 900 is. The phone is big--not as big as a Galaxy Note, but big. It's actually wider and thicker than the Samsung Galaxy Nexus, a phone with a substantially bigger screen.

Nokia Lumia 900: Back and Sides: Clockwise from top left: right edge (buttons are a volume rocker, power/hold button, and camera shutter), top edge (with a headphone jack, microphone, and microUSB port, and SIM card slot), back, and bottom edge (speaker grille). Click here to get a bigger view of the other sides of the Lumia 900.  Dan Nosowitz

I have small hands (we all have our hurdles in life), and for me, any phone with a screen bigger than four inches is more difficult to use than it's worth. In regular use, I find myself constantly readjusting my grip--I can't hold the phone and reach all parts of the screen with my thumb. Beyond the overall size increase, I don't think the bigger screen has any real benefits in this case. The Windows Phone keyboard is excellent; I never found it awkward to type on the smaller Lumia 800, so unless you have the sausage fingers of Billy Joel (YouTube it, the dude has ten kielbasas attached to his palms), I can't imagine this being a striking improvement. The screen is also mathematically worse than the Lumia 800's. It's the same exact screen--a PenTile AMOLED screen with 800 x 480 resolution and Nokia's ClearBlack tech, which, if you don't understand that, congratulations for not having so much nonsense rattling around in your head. What matters is that it's the same number of pixels stretched across a larger canvas—the opposite of Apple's approach with its Retina Display—which means a visible downgrade in image quality.

So on the Lumia 900, the picture is worse. It creates a bigger bulge in my pocket. What's the point?

All the buttons are on the right edge of the phone, even the power/hold button, which is often found on the top edge. That's essential, because it's not really possible for anyone besides Hakeem Olajuwon to reach the top edge of the phone while holding it with one hand. But with it placed on the side, I found myself accidentally hitting the hold switch often, since it falls directly under your right thumb.

The design is also somehow not quite as enthralling as the sleek Lumia 800, even though it's nearly identical. It's the little things, which add up to a different impression when you're dealing with a very simple design presentation. Example: the 800's screen was curved, with the screen seeming to melt off into the sides of the phone like an infinity pool. The 900 has a typical flat screen, with a more definitive bezel between the screen and the sides of the phone, and a weird raise ridge around the edges. It's a very minimalist design, which worked for the 800, because it had nice little touches and felt compact and sharp. The Lumia 900 isn't bad-looking, and it's certainly well-crafted, but it's also not that interesting.

The camera remains not very good. I was surprised at this with the Lumia 800, and I'm still surprised--the Nokia N8, probably the worst phone I've ever reviewed, had a stellar camera, and Nokia is well-known for their phone cameras. The Lumia 900's is average at best--I love that it has a dedicated shutter button, and shutter speed is pretty good, but I wasn't impressed with image quality. The Lumia often came up with very dark shots, and color reproduction was sometimes off. And in lower-light situations, photos were extremely noisy.

Nokia Lumia 900 vs. iPhone 4S: Near and Far: A couple more comparisons: the Lumia 900 took the two photos on the left, while the iPhone 4S took the two on the right. You can see that the Lumia works okay in full sunlight, but still has troubles with shadows and differences in light (look at the slanted shadow on the building to the right of the Empire State Building, or how the daffodils blend into the brighter sidewalk in the upper left corner). Click here to get a bigger view.  Dan Nosowitz

The hardware handles the Windows Phone operating system pretty nicely; it's responsive and fast, for the most part. The way it scrolls still feels not quite as organic as iOS--there's a little lag, and sometime the "flick" motion results not in a super-fast scroll, like you wanted, but a slow trudge downwards through a list. Otherwise the software has the same ups and downs (and it's mostly ups, to be clear) as any other Windows Phone, plus a few Nokia-specific apps (Nokia Drive, a free turn-by-turn GPS app; yet another mapping app, Nokia Maps; and a little Nokia-curated section of the App Marketplace).

THE PRICE

It's available on AT&T for $100 with a two-year contract. That's half the price of other 16GB phones like the iPhone, and probably a good way for Microsoft and Nokia to worm their way back into the public consciousness. It's a good deal, though given the fact that you're signing a two-year contract that'll cost you several thousand dollars in voice and data plans, it doesn't really make sense to care much about an extra $100 up front.

Nokia Lumia 900 Email App:  Dan Nosowitz

THE VERDICT

The Lumia 900 is a pretty good phone--I still think the iPhone is a smarter buy on AT&T, due to its gigantic and thriving App Store, sleeker hardware, and more polished software, but the Lumia 900 is very nice. And yet I don't think it's as good a phone as the Lumia 800 (though the LTE speeds are delightful). It's a weird feeling to be disappointed while still recommending a product, but that's how it goes--the 900 doesn't live up to my expectations, but it's still the best Windows Phone in America. Still, it feels a little dull, where the Lumia 800 felt fresh and new and stylish. But most of all, I'm turned off by the size. Dear phone manufacturers: I know it's an easy sell to say that your phone is bigger and therefore better--but for some of us, it's simply not the case.

First Bedside Genetic Test Could Prevent Heart Complications

A genotyping test from a Canadian biotech company enables timely personalized drug treatment.

• WEDNESDAY,

Audio »

For some cardiac patients, recovery from a common heart procedure can be complicated by a single gene responsible for drug processing. The risk could be lowered with the first bedside genetic test of its kind. The test shows promise for quickly and easily identifying patients who need a different medication.

Quick test: This shoebox-sized device from Spartan Bioscience supports the first bedside genetic test.
Spartan Bioscience

After a patient receives a heart stent—a small scaffold that props open an artery—his or her doctor will prescribe a blood thinner to prevent platelets from building up inside the device. However, for some 70 percent of patients with Asian ancestry and 30 percent of patients with African or European ancestry, a single genetic variant will prevent one of the most commonly prescribed blood thinners from working. Alternatives exist, but they are more expensive, so hospitals could use an easy way to identify who does and does not need the more expensive drug.

Canada's Spartan Bioscience has developed a near "plug-and-play" genotyping device that allows nurses and others to quickly screen patients at the bedside, perhaps while they are undergoing the stent placement procedure. Users take a DNA sample from a patient's cheek with a specialized swab, add the sample to a disposable tube, and then place the tube and sample in a proprietary shoebox-sized machine and hit a button. Shortly thereafter, the user receives a printout of the patient's genetic status for the drug-processing variant. The whole procedure takes about an hour. Most clinicians currently have to wait several days for similar information to come from off-site genetics testing companies.

"For six years we've been plugging away at this, and we finally broke through about a year and a half ago," says Spartan Bioscience founder Paul Lem. He says the simple test came to life with innovations at every step—from the special swab that collects the right amount of DNA, to the chemicals in the disposable reaction tube, to the software that automates the DNA reading—and a team with diverse backgrounds including his in medicine and molecular biology and others' in optical hardware.

Lem has kept an eye on other companies trying to create a bedside genetic test, some going after the same variant, and calculates that over $1 billion in capital has been spent over the last five years in this area.

The University of Ottawa Heart Instituteresearchers conducted a proof-of-principle trial for the device and found that the bedside test is effective at quickly identifying carriers of the drug-processing variant and can be performed by nurses with minimal training. The findings were published in The Lancetlast week.

"The stakes are pretty high" for the risks associated with the variant in the test, says Euan Ashley, a cardiologist with Stanford's Center for Inherited Cardiovascular Disease. Patients who receive a stent implant after a heart attack or as a preventive measure are at risk for serious adverse events if their bodies cannot process a commonly prescribed anti-platelet drug into its active form. "There's a startling number of people who carry the variant, which leaves them at risk," says Ashley. "Being able to get an answer within an hour or two—when you are thinking of a patient's heart—is a pretty compelling case for [testing for it]."

Ashley notes that there may come a day when a patient's entire genome could be sequenced at the bedside, which may encourage a different model for bedside genotyping. "But we aren't there yet," he says. Genome-sequencing technologies capable of clinical diagnoses currently require days to identify all the base pairs in a human genome. "Sometimes, speed is of the essence," says Ashley. The technology is a good example of a real opportunity to do actual personalized medicine in real time, he says.
Spartan Bioscience got regulatory approval for the test in the European Union in December 2010, and hopes to have approval in the United States by the end of this year. The company gives away the devices for free, and charges $200 per test.
Spartan Bioscience is also looking for other applications for the technology, says Lem, from infectious diseases like MRSA, an antibiotic resistant strain of staph infections, to pharmacogenetic markers such as a hereditary resistance to standard hepatitis C treatment.
"Doctors from around the world have been pinging us with all the applications they've been saving up to the day when a bedside DNA test is finally available," says Lem.

Quantum Computer Built Inside a Diamond

Scientists have built a quantum computer in a diamond, the first of its kind. The chip in the image measures 3mm x 3mm, while the diamond in the center is 1mm x 1mm. (Credit: Courtesy of Delft University of Technology and UC Santa Barbara)

Science Daily— Diamonds are forever -- or, at least, the effects of this diamond on quantum computing may be. A team that includes scientists from USC has built a quantum computer in a diamond, the first of its kind to include protection against "decoherence" -- noise that prevents the computer from functioning properly.

The demonstration shows the viability of solid-state quantum computers, which -- unlike earlier gas- and liquid-state systems -- may represent the future of quantum computing because they can be easily scaled up in size. Current quantum computers are typically very small and -- though impressive -- cannot yet compete with the speed of larger, traditional computers.

The multinational team included USC Professor Daniel Lidar and USC postdoctoral researcher Zhihui Wang, as well as researchers from the Delft University of Technology in the Netherlands, Iowa State University and the University of California, Santa Barbara. Their findings will be published on April 5 in Nature.

The team's diamond quantum computer system featured two quantum bits (called "qubits"), made of subatomic particles.

As opposed to traditional computer bits, which can encode distinctly either a one or a zero, qubits can encode a one and a zero at the same time. This property, called superposition, along with the ability of quantum states to "tunnel" through energy barriers, will some day allow quantum computers to perform optimization calculations much faster than traditional computers.

Like all diamonds, the diamond used by the researchers has impurities -- things other than carbon. The more impurities in a diamond, the less attractive it is as a piece of jewelry, because it makes the crystal appear cloudy.

The team, however, utilized the impurities themselves.

A rogue nitrogen nucleus became the first qubit. In a second flaw sat an electron, which became the second qubit. (Though put more accurately, the "spin" of each of these subatomic particles was used as the qubit.)

Electrons are smaller than nuclei and perform computations much more quickly, but also fall victim more quickly to "decoherence." A qubit based on a nucleus, which is large, is much more stable but slower.

"A nucleus has a long decoherence time -- in the milliseconds. You can think of it as very sluggish," said Lidar, who holds a joint appointment with the USC Viterbi School of Engineering and the USC Dornsife College of Letters, Arts and Sciences.

Though solid-state computing systems have existed before, this was the first to incorporate decoherence protection -- using microwave pulses to continually switch the direction of the electron spin rotation.

"It's a little like time travel," Lidar said, because switching the direction of rotation time-reverses the inconsistencies in motion as the qubits move back to their original position.

The team was able to demonstrate that their diamond-encased system does indeed operate in a quantum fashion by seeing how closely it matched "Grover's algorithm."

The algorithm is not new -- Lov Grover of Bell Labs invented it in 1996 -- but it shows the promise of quantum computing.

The test is a search of an unsorted database, akin to being told to search for a name in a phone book when you've only been given the phone number.

Sometimes you'd miraculously find it on the first try, other times you might have to search through the entire book to find it. If you did the search countless times, on average, you'd find the name you were looking for after searching through half of the phone book.

Mathematically, this can be expressed by saying you'd find the correct choice in X/2 tries -- if X is the number of total choices you have to search through. So, with four choices total, you'll find the correct one after two tries on average.

A quantum computer, using the properties of superposition, can find the correct choice much more quickly. The mathematics behind it are complicated, but in practical terms, a quantum computer searching through an unsorted list of four choices will find the correct choice on the first try, every time.

Though not perfect, the new computer picked the correct choice on the first try about 95 percent of the time -- enough to demonstrate that it operates in a quantum fashion.

நுரையீரலைப் பாதுகாப்போம்..

 
 
ஒரு நிமிடத்திற்கு சராசரியாக 18 முதல் 20 சுவாசம் என சீராக வைப்பது மூளையில் உள்ள முகுளத்தின் வேலை.

மொத்த நுரையீரலின் கொள்ளளவு சராசரியாக 6 லிட்டர் தான். மிகவும் இழுத்து மூச்சுவிடும் போது காற்றின் அளவு 5 லிட்டர்தான். எப்போதும் நுரையீரலுக்குள்ளே இருந்துகெண்டிருக்கும் காற்றின் அளவு 1 லிட்டர். பொதுவாக நுரையீரலில் சுரக்கும் சளி போன்ற நீர்மம் சில தூசிகளை அகற்றி வெளியேற்றும். 

இதுபோல் மூச்சுக் குழாய்களில் மேல் சிலியா என்ற பொருள் இருக்கும். இதுவும் மிக நுண்ணிய தூசியைக் கூட அகற்றிவிடும். இது மூச்சுக் குழாய்களில் வரும் தூசியை மேல்நோக்கி திருப்பி அனுப்பிவிடும்.

நாம் அறியாமலே சில சமயங்களினித உடலின் செயல்பாடுகளுக்கு ஒவ்வொரு உறுப்பும் இன்றியமையாததாகும். இதில் உடலுக்கு மெயின் சுவிட்சு போல் செயல்பட்டு, காற்றை உள்வாங்கி, வெளிவிட்டு உடலுக்கு உயிர் சக்தியைத் தரும் மோட்டார்தான் நுரையீரல்.

வாயுப் பரிமாற்றம் (Exchange of gas) நுரையீரலின் முக்கிய பணியாகும். மேலும் சில முக்கிய வேதிப் பொருட்களை உருவாக்குவதற்கும், வேறு சில வேதிப் பொருட்களை செயலிழக்கச் செய்வதும் இதன் மற்ற பணிகளாகும். நுரையீரலானது உடலியக்கத்திற்கு ஆற்றல் தரும் ஆக்ஸிஜனை உள் எடுத்துக் கொள்வதற்கும் கார்பன்-டை- ஆக்ஸைடை வெளியேற்றுவதற்கும் முக்கிய உறுப்பாக செயல்படுகிறது.

ஒரு நாளைக்கு சராசரியாக ஒரு மனிதன் 22,000 முறை மூச்சு விடுகி றான். கிட்டத்தட்ட 255 கன மீட்டர் (9000 கன அடி) காற்றை உள்ளிழுத்து வெளிவிடுகிறான்.

நுரையீரலின் செயல்பாடு.
மூக்கின் வழியாக நாம் உள்ளிழுக்கும் காற்று மூச்சுக் குழாய் (Trachea) வழியாக நுரையீரலுக்கு செல்கிறது. மூச்சுக் குழாய் மார்புப் பகுதியில் இரண்டாக பிரிந்து வலது, இடது நுரையீரலுக்குச் செல்கிறது. நுரையிரலுக்குள் நுழைந்தவுடன் மூச்சுக்குழல் ஒவ்வொன்றிலிருந்தும் கிளைகள் பிரியும். பின்னர் அவற்றிலிருந்து இன்னும் சிறு கிளைகள் என நிறைய பிரிவுகள் ஒரு மரத்தின் பெரிய கிளையிலிருந்து பரந்து பிரிந்து சின்னச்சின்ன தளிர்கள் வருவதுபோல் பிரிகின்றன.


அதனாலேயே இதனை மூச்சுமரம் (Respiratory tree) என்று அழைக்கின் றோம். முதல் நிலை மூச்சுக் குழல் (Primary bronchi), இரண்டாம் நிலை மூச்சுக் குழல் (secondry bronchi), மூன்றாம் நிலை மூச்சுக் குறுங்குழல் (bronchiole) என்று படிப்படியாகப் பிரிந்து கடைசியாக சின்னச் சின்ன பலூன்கள் மாதிரி தோன்றும் குட்டிக்குட்டி அறைகளுக்குள் இந்த குழல்கள் நீட்டிக் கொண்டிருக்கும். இவற்றை காற்று நுண்ணறைகள் (Alveoli) என்று அழைக்கிறோம்.

நாம் இழுக்கும் மூச்சுக்காற்று மூச்சு மரம் வழியாக காற்று நுண்ணறை களுக்குள் வந்துவிடும். உடலில் பல பாகங்களிலும் இருந்து பயன்படுத் தப்பட்ட ரத்தம் இதயத்தின் வலது வெண்டிரிக்கலை அடையும். அங்கிருந்து நுரையீரல், தமணி மூலம் நுரையீரலுக்கு கொண்டு செல்லப்படுகிறது.

நுரையீரல் தமணியும், வலது கிளை, இடது கிளை, என்று இரண்டாகப் பிரிந்து இரண்டு நுரையீரலுக்கும் செல்கிறது. இதுவும் பலமுறை கிளைகளாகப் பிரியும். இப்படிப் பிரியும்போது காற்று நுண்ணறைகளின் பக்கத்தில் தமணிகளின் மிக மிகச் சிறிய கிளைகள் அமைந்திருக்கும். இந்தச் சின்ன தமணிக் கிளைகள்தான் தந்துகிகள் (Capillaries) எனப்படுகிறது.

காற்று நுண்ணறை பக்கத்திலேயே தந்துகிகள் இரண்டின் சுவர்களும் மிக மிக நுண்ணியவையாக இருக்கும். அடுத்தடுத்து நுண்ணறைக்குள் காற்று நிறைந்திருக்கும் தந்துகிக்குள் ரத்தம் நிறைந்திருக்கும். வெளியிலிருந்து மூச்சுக்குழல் மூலம் உள்ளிழுக்கப்பட்ட காற்றில் நிறைய ஆக்ஸிஜன் இருக்கும். எனவே, நுண்ணறைக்குள்ளும் அதே அளவு ஆக்ஸிஜன் இருக்கும். தந்துகியில் உள்ள ரத்தத்தின் ஆக்ஸிஜன் அளவு குறைவு. கார்பன்டை ஆக்ஸைடின் அளவு அதிகம். உடலுக்கு வேண்டாத உடலிலிருந்து வெளியேற்றப்பட வேண்டிய மற்ற சில பொருட்களும் தந்துகியில் உண்டு.

இந்த நிலையில் நுண்ணறை – தந்துகி சுவர்களின் வழியாக ஒரு பரிமாற் றம் நடக்கிறது. நுண்ணறையில் அடர்த்தியாக இருக்கும் ஆக்ஸிஜன் தந்துகிக்குள் பாயும். தந்துகியில் அடர்த்தியாக இருக்கும் கார்பன்டை ஆக்ஸைடு நுண்ணறைக்குள் பாயும். இதுதான் வாயுப் பரிமாற்றம் (Exchange & gases). இதைத்தான் ரத்த சுத்திகரிப்பு என்று அழைக்கிறோம்.

ஆக்ஸிஜன் ஊட்டப்பட்ட ரத்தம் நுரையீரலிலிருந்து சிரைகள் மூலமாக இதயத்தின் இடது வெண்டிரிக்கிளுக்குள் எடுத்துச் செல்லப் படுகிறது. அங்கிருந்து மீண்டும் உடலின் பல பாகங்களுக்கு தமனிகள் மூலம் இந்த சுத்த ரத்தம் எடுத்துச் செல்லப்படுகிறது.

நுரையீரலைச் சுற்றி இரண்டு உறைகள் உள்ளன. 1. வெளிப்படலம் (Outer pleura) 2. உள்படலம் (Inner pleura) இந்த இரண்டு படலங்களுக்கும் இடையே ஒரு இடம் உண்டு. அதற்கு ஃப்ளூரல் இடம் என்று பெயர். இதனுள் மிகச் சிறிய அளவு ஃப்ளூரல் திரவம் இருக்கும். இந்தத் திரவம்தான் சுவாசத்தின் போது நுரையீரல்களின் அசைவினால் உராய்வு ஏற்படாமல் தடுக்கிறது. சுவாசத்தைக் கட்டுப்படுத்தி சீராக வைப்பதே முகுளப்பகுதி. அதால் அதை விழுங்கிவிடுவோம். உடல் நலம் சரியில்லாமல் போனால் மட்டுமே அவை சளியாக மூக்கின் வழியாக வெளியேறும். இதையும் தாண்டி ஏதேனும் தூசு உள்ளே நுழைந்தால் இருமல், தும்மல் முதலியவற்றால் வெளியேற்றப் பட்டுவிடும். நுரையீரலின் பணிகள் காற்றில் உள்ள ஆக்ஸிஜனை (ஆக்ஸிஜன்= உயிர்வளி, பிராணவாயு) இரத்தத்தில் சேர்ப்பதும், இரத்ததில் உள்ள கார்பன்-டை ஆக்ஸைடை (கரியமில வாயு) பிரித்து உடலிலிருந்து வெளியேற்றுவதும் நுரையீரலின் முக்கிய பணியாகும்.

இதயத்திற்கு இரு புறமும் பாதுகாப்பாக இருந்து இதயத்தை அதிர்வுகளிலிருந்து காப்பாற்றுகிறது. சில முக்கிய வேதிப் பொருட்களை உற்பத்தி செய்வது, வேறு சில வேதிப் பொருட்களை செயலிழக்கச் செய்வது போன்ற உடலுக்கு உயிர்தரும் வேலைகளை நுரையீரல் செய்து வருகிறது. நுரையீரல் பாதிப்பு உலகில் இலச்சக்கணக்கான மக்கள் ஒவ்வொரு வருடமும் நுரையீரல் சம்பந்தப்பட்ட நோயின் தாக்குதலுக்கு ஆளாகின்றனர். காற்று மாசுபாடு காற்று மாசுபாடு அதாவது சிலிகா, ஆஸ்பெட்டாஸ், கந்தகம், போன்றவற்றைப் பயன்படுத்தும் தொழிற் சாலைகளில் பணி புரிபவர்களின் நுரையீரல்கள் அதிகம் பாதிக்கப்படுவதாக தகவல்கள் தெரிவிக்கின்றன. புகை பிடிப்பது உடல் நலத்துக்கு கேடு என்ற செய்தி அனைவரும் அறிந்ததே


புகைபிடிப்பது:
புகை பிடிக்கும்போது நிறைய கரித் துகள்கள் (Carbon particles) நுரையீரலுக்குள் சென்று அங்கேயே படிந்து விடுகின்றன. இதனால் ஆக்ஸிஜன்- கார்பன்டை ஆக்ஸைடு பரிமாற்றம் தடைபடுகிறது. மற்றும் சிகரெட், சுருட்டு, இவற்றிலுள்ள நிகோடின் என்ற வேதிப்பொருள் ரத்தத்தில் உள்ள ஆக்ஸிஜன் அளவைக் குறைத்து கனிமப் பொருள்களின் அளவுகளில் மாற்றத்தை ஏற்படுத்தி, ரத்தக் குழாய்களின் அடைப்பை உண்டாக்குகிறது. புகைப் பழக்கத்தால் மூச்சுக்குழல் அலர்ஜி, காற்றறைகளின் சுவர்கள் சிதைந்துபோதல், எம்ஃபசிமா, நுரையீரல் புற்றுநோய் ஆகியவை உண்டாகின்றன. புகைப் பிடிப்பவர்களுக்கு மட்டுமல்ல, பக்கத்தில் இருப்பவர்களுக்கும் (Passive smoking) இதே தீங்குகள் நேரிடும்.


நுரையீரல் பாதிப்பின் அறிகுறிகள் இருமல் மூச்சு வாங்குதல் மூச்சு இழுப்பு நெஞ்சுவலிஹீமாப்டிஸிஸ் (இருமும்போது ரத்தம் வெளியேறுதல்) நுரையீரலைத் தாக்கும் சில முக்கிய நோய்கள் மூச்சுக்குழாய் அலர்ஜி(Bronchitis), நுரையீரல் அலர்ஜி (Pneumonia), காற்றறைகள் சிதைந்து போதல்(Emphysema), மூச்சுக்குழல்கள் சுருங்கிக் கொள்ளுதல் (Asthma).

நுரையீரலை பாதுகாக்க சில எளிய வழிகள்

தூசு நிறைந்த பகுதிகளுக்கு செல்லும் போது மூக்கில் துணியைக் கட்டிக்கொள்வது (Mask) நல்லது. பிராணயாமம், நாடி சுத்தி, ஆழ்ந்த மூச்சுப் பயிற்சி போன்றவற்றை தினமும் கடைப்பிடிப்பது. புகைப் பிடிப்பதை தவிர்ப்பது உடலில் நோய் எதிர்ப்பு சக்தியை அதிகரிக்கும் உணவு வகைகளை சாப்பிடுவது இன்றைய சூழ்நிலையில் மாசடைந்த காற்று அதிகம் இருப்பதால் நுரையீரல் சம்பந்தப்பட்ட நோய்களின் தாக்குதலும் அதிகம் இருக்கிறது.

இதனால் எதிர்காலத்தில் மினரல் வாட்டர் பாட்டிலைப் போல் ஆக்ஸிஜனை பாக்கெட்டுகளில் வாங்க வேண்டிய நிலை ஏற்படலாம். இந்நிலை மாற சுற்றுப்புறத்தை தூய்மையாகவும், பசுமை நிறைந்த பகுதிகளாகவும் மாற்றினாலே போதும்.. ஆரோக்கிய வாழ்வைப் பெற்றிட முடியும்.