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Saturday, March 3, 2012

Pioneering research reveals bacterium’s secrets



 by  



Ground-breaking research by an international team of scientists will help to make one of the most versatile of bacteria even more useful to society and the environment.
Though it lives naturally in the soil, the bacterium Bacillus subtilis is widely used as a model laboratory organism. It is also used as a ‘cell factory‘ to produce vitamins for the food industry and, in biotechnology, to produce enzymes such as those used in washing powders.
The BaSysBio research project, carried out by a consortium of researchers from eight European countries and Australia including the Department of Chemistry at the University of York, is unprecedented in its scope and has given scientists an unrivalled level of understanding of the way the organism can adapt to diverse conditions. Continue reading below….

Billions of years of evolution have shaped the performance of B. subtilis cells and the research has provided novel insights into the regulatory processes that help them to maintain their metabolism in prime condition.
Published in two papers in the latest edition of Science, the findings will enable scientists to engineer B. subtilis to become an even more effective producer of metabolites for a wide range of industries from pharmaceutical and chemical manufacturing to the agri and food sectors. The work also has medical implications as it will help scientists to understand how bacteria deal with changing conditions during infection.
B. subtilis is able to survive and grow in diverse and changing environments. The research used expertise from different fields ranging from molecular biology to bioinformatics and mathematics to investigate the cell as a system of interacting molecular components and the strategies it uses to adapt to varying conditions.
The researchers acquired and analysed large experimental data sets which were used with mathematical models to capture the complexity of the cellular system. They analysed the genes expressed under more than 100 different conditions that mimic the natural and laboratory environment of the organism.
It was already known that the B. subtilis genome carries around 4,200 genes but the new research identified 512 new potential genes in the bacterium.
The project co-ordinator Dr Philippe Noirot, of the INRA Centre at Jouy-en-Josas, near Paris, says: “Besides their scientific novelty, these two studies also represent a potential blueprint for bacterial systems biology. Our work will potentially make B. subtilis an even more efficient producer of enzymes. The results and approaches used in our studies, suggest it is now possible to design specific experiments to unravel other, previously more intractable, cellular processes.”
Professor Tony Wilkinson, of the York Structural Biology Laboratory, says: “The work has thrown up surprises. In one instance, where we expected that a few simple tweaks would be sufficient to achieve an adaptation, we observed wholesale changes involving almost half the genes in the organism.”
Professor Uwe Sauer, of the Eidgenössische Technische Hochschule, Zürich, says: “The work represents a conceptual step forward in how to assess and understand cellular adaptation to new situations that is fundamental to basic science as well as applications in biotech and medical research.”
Prof Jan Maarten van Dijl, of the University Medical Centre in Groningen, adds: “These studies help us to understand how bacteria deal with changing conditions during infection such as when normally commensal bacteria such as Staphylococcus aureus that live in the nose and throat adapt and invade the body and cause disease. This provides a foundation for research into the development of agents to combat these invasive bacteria.”
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The work has been backed by a €12 million grant from the European Union. 

The Patient of the Future



Internet pioneer Larry Smarr's quest to quantify everything about his health led him to a startling discovery, an unusual partnership with his doctor, and more control over his life.
  • BY JON COHEN
Gym rat: In his quest to optimize his health, Larry Smarr recently underwent tests to measure his peak oxygen consumption, maximum heart rate, and other physiological indicators. Credit: Michael Kelley
Back in 2000, when Larry Smarr left his job as head of a celebrated supercomputer center in Illinois to start a new institute at the University of California, San Diego, and the University of California, Irvine, he rarely paid attention to his bathroom scale. He regularly drank Coke, added sugar to his coffee, and enjoyed Big Mac Combo Meals with his kids at McDonald's. Exercise consisted of an occasional hike or a ride on a stationary bike. "In Illinois they said, 'We know what's going to happen when you go out to California. You're going to start eating organic food and get a blonde trainer and get a hot tub,' " recalls Smarr, who laughed off the predictions. "Of course, I did all three."
Smarr, who directs the California Institute for Telecommunications and Information Technology in La Jolla, dropped from 205 to 184 pounds and is now a fit 63-year-old. But his transformation transcends his regular exercise program and carefully managed diet: he has become a poster man for the medical strategy of the future. Over the past decade, he has gathered as much data as he can about his body and then used that information to improve his health. And he has accomplished something that few people at the forefront of the "quantified self" movement have had the opportunity to do: he helped diagnose the emergence of a chronic disease in his body.
Like many "self-quanters," Smarr wears a Fitbit to count his every step, a Zeo to track his sleep patterns, and a Polar WearLink that lets him regulate his maximum heart rate during exercise. He paid 23andMe to analyze his DNA for disease susceptibility. He regularly uses a service provided by Your Future Health to have blood and stool samples analyzed for biochemicals that most interest him. But a critical skill separates Smarr from the growing pack of digitized patients who show up at the doctor's office with megabytes of their own biofluctuations: he has an extraordinary ability to fish signal from noise in complex data sets.
On top of his pioneering computer science work—he advocated for the adoption of ARPAnet, an early version of the Internet, and students at his University of Illinois center developed Mosaic, the first widely used browser—Smarr spent 25 years as an astrophysicist focused on relativity theory. That gave him the expertise to chart several of his biomarkers over time and then overlay the longitudinal graphs to monitor everything from the immune status of his gut and blood to the function of his heart and the thickness of his arteries. His meticulously collected and organized data helped doctors discover that he has Crohn's, an inflammatory bowel disease.
I have ulcerative colitis, a cousin of Crohn's, and I am intrigued by what Smarr calls his "detective story." His investigation of his body has evolved into a novel collaboration with a leading gastroenterologist to better understand and treat his disease, and maybe even to help others like me. But I am also a disease-weary skeptic. After 22 years of seeing specialists, enduring a battery of tests, unscrambling the complex medical literature, and trying a hodgepodge of interventions, I have had no luck staving off flares and only modest success controlling them with blunt-force drugs. Like others who have chronic illnesses, I am acutely sensitive to false hope. I have been repeatedly baffled by the course my disease takes and thoroughly confused by tests meant to clarify my condition.
When I first meet Smarr and he gives me a tour of his institute, commonly known as Calit2, I tell him that I find it difficult to separate promise from hype, noting that his endeavor has all the pitfalls of any "n = 1" experiment—a test in which only one person is the subject. "Every disruption begins with an n of 1," he replies.
Smarr has a standard-issue office on the side of a sleek six-story building, but much of his floor resembles a hip architectural firm. Workstations zigzag across a vast space that features exposed venting pipes and electrical conduits on the naked ceiling. His chief assistant, who lives near San Francisco, talks to coworkers via Skype and a dedicated computer monitor. Across the room, chairs are arranged before a wall of 30-inch displays stacked five high and 14 wide, with a total of 286.7 million pixels that can simultaneously show dozens of brain scans or the stars in a galaxy.
Though he has no laboratory of his own, he shows off the projects at Calit2 as though each were one of his children. The labs investigate everything from machine perception and game culture to integrated nanosensors and 3-D virtual reality. One, which Smarr recently tapped to determine his peak oxygen consumption and maximum heart rate, studies ways to improve individual and population health. Another researches digitally enabled genomic medicine—a blend of self-quantification devices with wireless technology and DNA data.
The place makes my imagination dance. So, too, does Smarr's medical sleuthing of his own body. Not only does he want to convince others that they can fundamentally alter the patient-doctor relationship and transform physicians into partners, but he's also going public with his biodata, hoping to crowdsource information that will lead to new insights about the elusive links between DNA sequences, biomarkers, and disease. I soon buy into his vision, embarking on a closer examination of my own disease that, at the very least, scuttles my resignation to it.
MYSTERY SOLVED
Larry Smarr stumbled into his role as a proselytizer for digitizing and then crowdsourcing medicine; he stresses that by nature he is a reserved and private person. He was born and raised in Columbia, Missouri, where his parents ran a flower shop from the home basement. One of his greatest passions is the quiet, solitary cultivation of that most finicky and delicate of plants, the orchid. Yet he has no regrets about going public in writings and talks with extremely intimate details about his body. "Most people think I'm crazy," he says. But as a result of his candor, many people have contacted him, he says, and he shows me how a Google search on his name now pulls up articles about his quantified-health quest before everything else he has published in his distinguished career.
Smarr says he "got outed as a quantified self" after he spoke at a technology summit in May 2010. A session titled "Bio­NanoInfo Technology: The Big Challenges" featured him on a panel with Leroy Hood, a cofounder of the Institute for Systems Biology in Seattle and one of the inventors of the first automated DNA sequencer. Hood discussed his push for technology that he hopes will introduce an era of medicine he calls P4: predictive, preventive, personalized, and participatory. Smarr told his own story of using self-quantification to lose weight. A reporter interviewed him after the session, seeking more details, and in the wake of that article, speaking requests started to pour in.
Hood envisions a day when devices using nanotechnology will measure 2,500 markers in blood to track fluctuations in what he estimates are about 50 proteins in 50 of the body's organs. But that is not yet practical, so Smarr settled on about 100 biomarkers to understand how his dietary changes were affecting his body. Levels of one of the markers, C-reactive protein, or CRP,  stood out as higher than normal.
CRP triggers an immune response by binding to the surface of ailing cells, and the level of it should be less than one milligram per liter of blood. Smarr's level in November 2007 was 6.1. More alarming still, over the next seven months it steadily climbed to 11.8. He felt fine, but he decided to seek a doctor's advice, worried that something was amiss. The doctor dismissed Smarr's self-charted longitudinal CRP data, telling him to return if he had symptoms. "Doctors are the gatekeepers, and they're worried about getting disintermediated," he says, comparing them to the bank tellers who initially bad-mouthed ATMs.
Within a few months, a sharp, persistent pain in the left side of his abdomen sent him to the doctor's office, and he was diagnosed with acute diverticulitis, an infection of pockets in the wall of the colon. A blood test showed that his CRP had climbed to 14.5 during the attack. He took antibiotics, the symptoms resolved, and his CRP dropped to 4.9—but that was still unusually high. Concerned that these readings might, as he had read, indicate a plaque buildup that could lead to a heart attack, he had doctors do ultrasounds of his carotid artery and found that it was indeed thickening.
To better understand the attack, he had his stool analyzed for, among other things, lactoferrin, a marker of inflammation. His lactoferrin, too, rose several times to sky-high levels—200, whereas the normal count is less than 7.3. When he overlaid his results on a graph with his CRP fluctuations, he noticed that the two roller-coastered in tandem. A colonoscopy in December 2010 revealed extensive diverticulitis, but Smarr, who had trolled the medical literature online, remained unconvinced that this was his underlying disorder. He became particularly intrigued by studies that linked high lactoferrin levels to inflammatory bowel disease.
At this point, Smarr discovered that UCSD had recently hired a new head of gastroenterology, William Sandborn, who had published a compelling study that charted rises in lactoferrin levels during flares of inflammatory bowel disease. The two met and decided to do yet another colonoscopy. By then, Smarr's lactoferrin level had risen to a whopping 900. Sandborn reviewed the results and concluded that his new patient might have Crohn's disease. Smarr now thinks his diverticulitis attack was actually a Crohn's flare.
"It's a paradigm for what will happen in the future," Hood says of Smarr's story. "With P4 medicine, consumers are going to be the driving force—it isn't going to be physicians. They're going to demand to quantize themselves about their own wellness and what can be done."
Cardiologist Eric Topol, author of The Creative Destruction of Medicine (see "Technological Healing" ) and head of the Scripps Translational Science Institute down the street from UCSD, supports the self-quantification movement but says it has the most to offer people who, like Smarr, zoom in on specific issues. "My colleagues have a doctors-know-best attitude," says Topol. "Individuals like Larry have much more invested here, and they're going to put in time and resources to gather as much information as possible. Those clinicians who have the plasticity to adapt to this will be better doctors in the future."
Smarr recognizes that many people do not have his skills at amassing and analyzing data, nor do they have his resources—he estimates that his "burn rate" for tests and other expenses his health insurance would not pay for has ranged from $5,000 to $10,000 per year. Still, he thinks medical quests like his will become more common with the emergence of technologies that more easily and cheaply test biomarkers and sequence DNA. "My particular story is a good example of an early victory," he says. "I'm not saying we need to get rid of doctors. But imagine if you go in to the doctor and little widgets have been recording data to the cloud and the doctor can look at it. That's going to be a vastly more productive visit. There'll be a liberating effect on them."
GUT CHECK
Unlike the doctors who deemed Smarr's data mining a clinically useless "academic" exercise by an amateur, Sandborn welcomes his input. "I've learned an enormous amount from listening to patients over the years and just being open-minded about the journey that they go through with their illness," says the gastroenterologist. Yet Smarr's unusual project and personality have clearly encouraged Sandborn to explore a patient-doctor relationship of a kind he might have avoided with others. Sandborn notes that in many cases, overtesting wastes money, sends patients on tangents, and can lead to false positive results that actually cause harm. "None of those things apply in Larry's case," he says.
Sandborn has agreed to accompany Smarr on an expedition into another medical frontier: the microbiome. In 2010, Nature published a study that sifted through fecal samples from 124 people, plucking out the microbial genes in healthy individuals and those with Crohn's or ulcerative colitis. In the healthy group, the researchers found an average of 3.3 million microbial genes—about 150 times the number of genes in the human genome. People who had an inflammatory bowel disease harbored 25 percent fewer microbial genes, and the species of bacteria that were depleted differed in people with Crohn's and those with ulcerative colitis.
Smarr being Smarr, he decided to have his microbiome sequenced at the J. Craig Venter Institute. Sandborn, in turn, plans to work with researchers at the Venter Institute to assess whether they can pull something meaningful out of this most basic data, coupled with Smarr's biomarkers and the evolution of his disease. Future treatments, for example, might specifically repopulate the gut with the bacteria that people with the disease are lacking. Smarr also plans to have his entire genome sequenced by George Church, the Harvard University geneticist whose Personal Genome Project recruits people willing to share medical records and DNA sequences. "Larry and a few others are becoming very well-­measured individuals," says Church. "What we're trying to do is gather together such individuals and turn it into more of a collective process. If you keep data to yourself, it's hard to interpret."
Larry Smarr has not convinced me that I can manage my ulcerative colitis more effectively by following his lead. But his experience has prodded me to consider options I previously discounted or didn't know about. I had 23andMe analyze my single-­nucleotide polymorphisms, which spotlighted a mutant immune-system gene I carry that almost doubles my risk for ulcerative colitis. I joined the Personal Genome Project—which will also sequence my micro­biome—and agreed to make all my DNA and medical records public. I saw Sandborn as a patient, and we plan to monitor my CRP and lactoferrin during a flare and on medication. If I can find immune-modulating drugs on the market that specifically counteract the effects of my mutant gene and do not have serious side effects, ­Sandborn says, he's willing to try those on me too.
At the end of my consultation with Sandborn, it becomes clear that we share a sense of skepticism and hope about the new medical world that Larry Smarr has encouraged each of us to enter. "I have no doubt this is the future of medicine, but I have no idea how to get there from here," he says. "Then again, when you find the right patients, you can start to figure out how to move forward."
TR contributing editor Jon Cohen is a correspondent with Science. His latest book is Almost Chimpanzee: Redrawing the Lines that Separate Us From Them.

Solved: Mystery of the Nanoscale Crop Circles


When a thin layer of gold anneals on top of a silicon wafer coated with native silicon oxide, randomly distributed pools of eutectic alloy quickly form – and then go through a rapid series of strange changes, leaving behind bare silicon-dioxide circles surrounded by debris. Each denuded circle reveals a perfect square at its center. The area shown is about 107 by 155 micrometers (millionths of a meter). (Credit: Image courtesy of DOE/Lawrence Berkeley National Laboratory)                          Science Daily  — Almost three years ago a team of scientists at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) was performing an experiment in which layers of gold mere nanometers (billionths of a meter) thick were being heated on a flat silicon surface and then allowed to cool. They watched in surprise as peculiar features expanded and changed on the screen of their electron microscope, finally settling into circles surrounded by irregular blisters.

Until recently the cause of these strange formations remained a mystery. Now theoretical insights have explained what's happening, and the results have been published online by Physical Review Letters.The circles varied in diameter up to a few millionths of a meter, and in the center of each was a perfect square. The mysterious patterns were reminiscent of nothing so much as so‑called "alien" crop circles.
Eagerly melting alloys
When two solids are combined in just the right proportions, changes in chemical bonding may produce an alloy that melts at a temperature far lower than either can melt by itself. Such an alloy is called eutectic, Greek for "good melting." The eutectic alloy of gold and silicon -- 81 percent gold and 19 percent silicon -- is especially useful in processing nanoscale semiconductors such as nanowires, as well as for device interconnections in integrated circuits; it liquefies at a modest 363˚ Celsius, far lower than the melting point of either pure gold, 1064°C, or pure silicon, 1414°C.
"Gold-silicon eutectic liquid can safely solder chip layers together or form microscopic conducting wires, by flowing into channels in the substrate without burning up the surroundings," says Berkeley Lab's Junqiao Wu. "It's particularly interesting for processing nanoscale materials and devices." Wu cites the example of silicon nanowires, which can be grown from beads of eutectic liquid that form from droplets of gold. The beads catalyze the deposition of silicon from a chemical vapor and ride atop continually lengthening nanowire whiskers.
Understanding just how and why this happens has been a challenge. Although eutectic alloys are well studied as solids, the liquid state presents more obstacles, which are particularly formidable at the nanoscale because of greatly increased surface tension -- the same surface forces that make it difficult to form ultra-thin films of water, for example, because they pull the water into droplets. At smaller scales the ratio of surface area to bulk increases markedly, and nanoscale structures have been described as virtually "all surface."
These are the conditions that the team led by Wu, who is a faculty scientist in Berkeley Lab's Materials Sciences Division and a professor in the Department of Materials Science and Engineering at the University of California at Berkeley, set out to examine, by creating the thinnest possible films of gold-silicon eutectic alloys. The researchers did so by starting with a substrate of pure silicon, on whose flat surface an extremely thin barrier layer (two nanometers thick) of silicon dioxide had formed. On this surface they laid layers of pure gold, varying the thickness from one trial to the next between just a few nanometers to a hefty 300 nanometers. The silicon dioxide barrier prevented the pure silicon from mixing with the gold.
The next step was to heat the layered sample to 600 °C for several minutes -- not hot enough to melt the gold or silicon but hot enough to cause naturally existing pinholes in the thin silicon dioxide layer to enlarge into small weak spots, through which pure silicon could come in contact with the overlying gold. At the high temperature, silicon atoms quickly diffused out of the substrate and into the gold, forming a layer of eutectic gold-silicon alloy nearly the same thickness as the original gold and spreading in a virtually perfect circle from the central pinhole.
When the circular disk of eutectic alloy got large enough it suddenly broke up, disrupted by the high surface energy of the gold-silicon eutectic liquid. The debris was literally pulled to the edges of the disk, piling up around it to leave a central denuded zone of bare silicon dioxide.
In the center of the denuded zone, a perfect square of gold and silicon remained.
Chemistry and crystallography, not aliens
The researchers' most surprising discovery was that the thinner the original gold layer, the faster the eutectic circles expanded. The reaction rate when the gold layers were only 20 nanometers thick was more than 20 times faster than when the layers were 300 nanometers thick. And while at first glance the dimensions of the gold and silicon squares inside the circular denuded zones seemed variable, there was in fact a strict relation between the size of the square and the size of the circle: the radius of the circle was always the length of the square raised to the power of 3/2.
How did the squares get there in the first place? They originated as weak spots that were the sources of the spreading eutectic gold-silicon circles; when the circular eutectic was ruptured the squares filled with the same eutectic, which remained at the centers of the denuded zones. As they cooled, the gold and silicon within the squares separated, leaving sharply defined edges that were pure silicon; the centers were more roughly outlined squares of pure gold.
By slicing through the silicon/silicon dioxide/gold layercake and looking sideways at the structures with an electron microscope, the researchers found that the surface squares were the bases of inverted pyramids, resembling teeth penetrating the thin silicon dioxide layer and embedded in the silicon wafer. The squares were square, in fact, because of the silicon's orientation: the substrate had been cut along the crystal plane that defined the base. The four triangular sides of the pyramids lay along the low-energy planes of the crystal lattice and were defined by their intersections.
What began as a puzzling phenomenon reminiscent of "The X Files," if on a considerably smaller scale than the cosmic, the mystery of the "nanoscale crop circles" eventually yielded to careful observation and theoretical analysis -- despite the obstacles posed by high temperatures, nanoscale sizes, instabilities of the liquid state, and extremely rapid time scales.
"We found that the reaction rate in forming small-sized gold-silicon eutectic liquids -- and perhaps in many other eutectics as well -- is dominated by the thickness of the reacting layers," says Wu. "This discovery may provide new routes for the engineering and processing of nanoscale materials."

பண்டைய காலத்தில் வடஆபிரிக்காவுடன் யாழ்ப்பாணம் வணிக உறவில் ஈடுபட்டதற்கான அரிய சான்றுகள் அல்லைப்பிட்டியில் கண்டுபிடிப்பு.





பண்டைய யாழ்ப்பாணத்திற்கும் - வட ஆபிரிக்காவிற்குமிடையில் வர்த்தகத் தொடர்புகள் இருந்தமைக்கான ஆதாரங்கள் கண்டுபிடிக்கப்பட்டிருப்பதாக யாழ்.பல்கலைக்கழக வரலாற்றுத்துறை பேராசிரியர் புஸ்பரட்ணம் தெரிவித்துள்ளார்.
இந்த விடயம் தொடர்ாக அவர் மேலும் தெரிவிக்கையில்,
கடந்த வாராம் அல்லைப்பிட்டியில் கிணறு வெட்டியபோது எதிர்பாராமல் சில தொல்பொருட்ச் சின்னங்கள் வெளிவந்துள்ளன. அவற்றை அவதானித்த அல்லைப்பிட்டி பாரதி வித்தியாலய ஆசிரியர் நடராசா வாகிசன் அதுபற்றிய தகவலை எமது துறைக்குத் தெரியப்படுத்தினார்.
அங்கு சென்ற தொல்லியல் ஆய்வு உத்தியோகத்தர் ப.கபிலன், எஸ். மணிமாறன் ஆகியோர் அங்கு கிடைத்த சில தொல்பொருட்ச் சின்னங்களான மனித சிலையின் தலைப்பாகத்திற்குரிய சிற்பம் யாழ்ப்பாணத்தின் பழமை பற்றியும் பண்டைய காலத்தில் அது பிற நாடுகளுடன் கொண்டிருந்த வணிக, கலாசார உறவுகளை அறிந்து கொள்ளவும் பெரிதும் உதவுகின்றது.
14 சென்ரி மீற்றர் உயரமும், 12 சென்ரி மீற்றர் அகலமும் கொண்ட சிலையின் தலைப்பாகம் ஒரு வகை மங்கலான வெள்ளி போன்ற உலோகத்தால் செய்யப்பட்டுள்ளது. விஞ்ஞான ரீதியாக இதன் உலோகத் தன்மையை அடையாளப்படுத்தும்வரை இது பற்றி விரிவாக எதையும் கூறமுடியாதிருக்கிறது.
ஆயினும் இந்த மனித தலையின் உருவ அமைப்பு ஐரோப்பிய நாட்டு மக்களுக்கோ அல்லது ஆசிய நாட்டு மக்களுக்கோ உரியதல்லதென்பதை உறுதியாகக் கூறமுடியும்.
பொதுவாக இச்சிற்பத்தில் காணப்படும் முன்தள்ளிக்கொண்டிருக்கும் தாடை, பின்நோக்கிய நெற்றி, சுருண்ட முடி, தடித்த உதடு, பின்பக்கம் அகண்ட தலை, நீண்ட களுத்து, அகன்ற துவாரமுள்ள காது என்பன ஆபிரிக்க கலைமரபுக்குரிய தனித்துவமான பண்பாகும். இதனால் அல்லைப்பிட்டியில் கிடைத்த இச்சிற்பத்தை ஆபிரிக்கா குறிப்பாக வடஆபிரிக்கா மக்களுக்குரியதெனக் கூறலாம்.
வரலாற்று தொடக்க காலத்தில் இருந்து வடஆபிரிக்காவில் உள்ள பப்பரவர் அல்லது மொரெரக்கன் சமூகத்துடன் வடஇலங்கை தொடர்பு கொண்டதற்கான ஆதாரங்கள் காணப்படுகின்றன. யாழ்ப்பாண வைபவமாலை யாழ்ப்பாண அரசு காலத்தில் பப்பரவர் என்ற வணிக சமூகம் யாழ்ப்பாணம் வந்தது பற்றிக் கூறுகிறது.
சமஸ்கிருதத்தில் பப்பரதேசம் என்பது தமிழ் நிகண்டில் வடஆபிரிக்காவைக் குறிக்கிறது. இப்பப்பரவர் சமூகம் இஸ்லாமியர் அல்லாத சமூகம் என்பதை யாழ்ப்பாணவை பவமாலை வேறுபடுத்திக் காட்டுகிறது.
கி.பி.1790 க்கு உரிய ஒல்லாந்தர் கால யாழ்ப்பாணம் பற்றிய ஆவணமும் இஸ்லாமியரில் இருந்து இச்சமூகத்தை வேறுபடுத்திக் காட்டுகிறது. வணிக நோக்கோடு யாழ்ப்பாணம் வந்த இச்சமூகம் காலப்போக்கில் இங்கேயே நிரந்தமாகக் குடியேறியதற்கான சான்றுகள் காணப்படுகின்றன.
உதாரணமாக தீவகத்தில் சாலைக்கு அருகில் உள்ள பப்பரபிட்டி, நயினாதீவில் உள்ள பப்பரவன்சல்லி முதலான இடப்பெயர்கள் இதற்குச் சான்றாகும். சில சந்தர்ப்பங்களில் நயினாதீவே பப்பரவத்தீவு என அழைக்கப்பட்டமைக்கு ஆதாரங்கள் உண்டு.
இச்சமூகம் சமகாலத்தில் இந்தியாவில் குஜராத், தமிழகத்தில் இராமேஸ்வரம் போன்ற இடங்களிலும் குடியேறியதற்குச் சான்றுகள் உண்டு. இவ்வாதாரங்கள் போத்துக்கேயர் வருகைக்கு முன்னரே தென்னாசியாவில் குறிப்பாக வட இலங்கைக்கு வணிக நோக்கோடு வடமேற்கு ஆபிரிக்காவில் இருந்து வந்த பப்பரவர் சமூகத்தில் சில, காலப்போக்கில் யாழ்ப்பாணத்திலேயே நிரந்தரமாகக் குடியேறினர் எனக் கருத இடமளிக்கிறது.
அதை மேலும் உறுதி செய்வதில் அல்லைப்பிட்டியில் கிடைத்த ஆபிரிக்கக் கலை மரபுச் சிற்பத்திற்கு முக்கிய இடமுண்டு.
சமீபகாலத் தொல்லியற் கண்டுபிடிப்புக்கள் மேற்காசியா, ஆபிரிக்கா மற்றும் தென்கிழக்காசியா,கிழக்காசிய நாடுகளுக்கும் இடையிலான பண்டைய கால வணிக உறவில் வடஇலங்கை அதிலும் குறிப்பாக யாழ்ப்பாணத் தீபகற்பம் முக்கிய வணிகப் பரிமாற்று மையமாக இருந்ததை உறுதி செய்கின்றன.
இதற்கு அண்மையில் யாழ்ப்பாணக் கோட்டை அகழ்வாய்வில் கிடைத்த 2000 ஆண்டுகளுக்கு முற்பட்ட மேற்காசிய நாடுகளுக்கு உரிய தொல்லியற் சின்னங்களைக் குறிப்பிடலாம்.
1980களில் அல்லலைப்பிட்டியில் ஜோன்காஸ்வெல் மேற்கொண்ட அகழ்வாய்வில் 10-11 நூற்றாண்டைச் சேர்ந்த சீன நாட்டு கடற்கலத்தின் உடைந்த பாகங்கள், இந்நாட்டுப் பீங்கான்கள், நாணயங்கள் கண்டுபிடிக்கப்பட்டுள்ளன.
இந்நிலைiயில் அங்கு வடஆபிரிக்கக் கலைமரபில் அமைந்த சிலையொன்று கிடைத்திருப்பது தொடர்ந்தும் அல்லைப்பிட்டியில் ஆய்வு மேற்கொள்ள எம்மைத் தூண்டியுள்ளன என வரலாற்றுத்துறை பேராசிரியர் புஸ்பரட்ணம் தெரிவித்துள்ளார்.

Temple-Baraitser syndrome: a rare and possibly unrecognized condition.


Temple-Baraitser syndrome, previously described in two unrelated patients, is the association of severe mental retardation and abnormal thumbs and great toes. We report two additional unrelated patients with Temple-Baraitser syndrome, review clinical and radiological features of previously reported cases and discuss mode of inheritance. Patients share a consistent pattern of anomalies: hypo or aplasia of the thumb and great toe nails and broadening and/or elongation of the thumbs and halluces, which have a tubular aspect. All patients were born to unrelated parents and occurred as a single occurrence in multiple sibships, suggesting sporadic inheritance from a de novo mutation mechanism. Comparative genomic hybridization in Patients 1, 2 and 3 did not reveal any copy number variations. We confirm that Temple-Baraitser syndrome represents a distinct syndrome, probably unrecognized, possibly caused by a de novo mutation in a not yet identified gene.
































Temple and Baraitser (1991) reported a 3.5-year-old boy, born of
nonconsanguineous Iranian parents, with a severe mental retardation
syndrome characterized by hypotonia, seizures, and generalized cerebral
atrophy. He had a low frontal hairline with central cowlick, mild
hypertelorism, ptosis, and a prominent nose. Skeletal features included
small hypoplastic thumb nails and absent great toe nails. Radiographs
showed central lucent areas in the distal phalanges of both thumbs
resembling pseudoepiphyses. The terminal phalanges of other digits on
both hands and feet were hypoplastic.


Gabbett et al. (2008) reported a 4-year-old boy with a similar phenotype
to that reported by Temple and Baraitser (1991). He had marked
hypotonia, global developmental delay, and seizures. Other features
included myopathic facies with flat forehead, broad depressed nasal
bridge, epicanthal folds, short columella, long philtrum, broad mouth
with downturned corners, and high-arched palate. Both thumbs were
terminally broad with hypoplasia of the nail. The halluces were long and
broad with nail aplasia bilaterally. Radiographs showed pseudoepiphyses
of the thumbs and hypoplasia of all other terminal phalanges. Gabbett et
al. (2008) noted that the patient's mother had a seizure disorder and
took carbamazepine during pregnancy, which may have accounted for some
of the facial dysmorphism. Both Temple and Baraitser (1991) and Gabbett
et al. (2008) noted some phenotypic similarities to DOOR syndrome
(220500), but neither patient had deafness.

Important marriage ceremonies in Tamil iyers.



 
Some of the rituals were in vogue considering the young age of the bride and groom in the early days. But these have been followed even now also. Examples are Nalangu, bride and groom being carried after the Kaasi yathirai, Oonjal and the bride sitting on the father's lap.
Vrutham
The wedding rites/rituals/celebrations start off with prayers offered to ancestors to seek their and God's blessings for the upcoming wedding. This usually takes place in the early morning hours of the first wedding day. The bride's side does the rites for the bride's side of the family while the groom side does conducts its own prayers side-by-side.
Janavasam/"maapillai azhaippu" - the procession
This is the archetypical picture of Indian celebration packed with a kaleidoscope of color, glitz, music and dancing!
The groom would be seated on a horse-drawn chariot (or in some cases, beautifully adorned cars) as he makes a procession through the roads with his entourage. The accompanying entourage dances to the rhythm rendered by the accompanying band announcing to all the upcoming matrimony .
In recent times the bride gets a piece of action as she joins the groom halfway through the procession and gets to sit alongside the groom on the chariot. They then make their way to the temple where the groom - "maapillai" - is given a new set of traditional dhoti - "veshti" and shirt - to wear for the following nischayathartham ceremony. Off late some grooms go for Western styled suits also.
The reason for this ritual is from the practice of announcing in early days to all the village people on who is the bride and groom.
The procession then makes its way back to the mandapam (wedding hall) where the nischayathartham then ensues
Nischayathartham - The engagement ceremony
After all the joyous dancing and pompous procession, the guests settle down at the mandapam to witness and bless the rites and rituals involved in the "engagement ceremony" with the background of Sanskrit mantrams chanted by the Hindu priests.
During the Nichayathartham the following details of both bride and the groom are read out for the everyone Personal: Father's name, Grand father's name, the village to which their forefather's belonged, their gothra,aliasname etc.
Muhurtham: Date&Time(Georgian and Lunar),Lagnam, Star, Address of the marriage hall etc.
The bride and groom are officially engaged in God's name and the auspicious timing for the Muhurtham - the actual wedding rites - is set in everybody's presence. Everyone present in the Nichayathaartham is asked if anyone has any concern or objection and only after everyone is okay the "Thaamboolam" plates are exchanged.
"Thaamboolam" plates containing items required for the muhurtham are exchanged by both the groom's and bride's sides (generally the senior most male) during this function.
Muhurtham - The wedding proper
Muhurtham refers to the actual wedding ceremony itself. It typically occurs on the second day of a 2- or 3-day wedding ceremony and occurs generally early in the morning around 7–8 am depending on the priests' decree but may be even up to 11 AM.
The muhurtham includes the "Kasi yaatrai" , "maalai maatral", "oonjal ceremony" and the actual Muhurtham itself.
Kasi yaatrai
Refers to an age-old Brahmin ritual where the groom "decides" to take up 'sanyaasam' (i.e. asceticism, monkhood) for spiritual pursuit. He would ultimately be 'convinced' by the bride's father to return and take up "grahastham" or family life and that the bride will assist in his subsequent spiritual pursuit. For the Kaasi Yaathirai, the bride's father would have to buy(as in general practice)an Umbrella, Hand fan, Bhagwad Gita book, Sandals.
The maapillai (groom) will then agree and garlands will be exchanged by the bride and groom (maalai maatral). The process of maalai maatral may be complicated by the groom's side carrying the groom and the bride's side carrying the bride and each side making it difficult for the other side to correctly place the garland. Basically traditional family entertainment.
They would then head to a swing (oonjal) in the mandapam. Respected womenfolk of the household will then perform short rituals with classical singing to ward off "evil eyes" as the bride and groom are seated on the oonjal.
They then proceed to the podium in the mandapam where rites of the marriage - muhurtham - are performed. The climax is when the bride is seated on her dad's lap as her dad does (kannigadhaanam) and offers his daughter to be taken care of by the groom. As the priest then chants mantrams, the groom ties a "thaali" or "thirumaangalyam" as a necklace around the bride's neck as all the guests shower their blessings (symbolized by rice grains that are distributed to all guests to shower onto the bride and groom).
This symbolizes the actual wedding and the newly-weds take their marriage vows in seven steps (sapthapathi) as they walk three rounds hand-in-hand around the holy fire (agni).
Nalangu - wedding games
Nalangu is a tradition that dates back to times when marriages used to occur at a younger age (early teens). This component was incorporated to keep the mood light-hearted and fun for the newly wed young teens. It has stayed on as an integral component of South Indian weddings.
Traditional games include the newly-weds putting their hands into a small bowl to find a small object with the person finding the object first the winner. Other examples of games include breaking papadums over each other's heads and so on and so forth. It is an interesting component of the wedding gala.


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 Dont" keep me in ur eyes, i may fall as tears.Keep me in ur heart, so that ur every "heart beat" may reminds u that there is "someone 4 u"...



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Regards,
CS Sapna Shankar