Your brain is older than you think, say researchers from Stanford and the University of Chicago

Researchers find a genetic link between the human brain and a sea-dwelling worm. The finding suggests that, to capture the entire evolutionary picture, biologists need to cast a wider net, to include animals that don't look alike.

 An adult acorn worm with its proboscis on the bottom right and tail on the top left.

Biologists may need to rethink where to look for evolutionary changes responsible for the origin of vertebrates, including humans, as a result of research at Stanford University and the University of Chicago.

Chris Lowe and Ari Pani, biologists at Stanford's Hopkins Marine Station, discovered some of the essential genetic machinery previously thought exclusive to vertebrate brains in a surprising place – a sea dwelling, bottom-feeding acorn worm, Saccoglossus kowalevskii.

These worms lack vertebrate-like brains, and are, in fact, separated from vertebrates by over 500 million years of evolution. The worms are even classified in a different phylum, the hemichordates.

"The closer we looked, the more similarities we found between these strange worms and vertebrate brains in their underlying molecular blueprints," said Lowe, an assistant professor of biology. "This suggests that essential parts of these blueprints, previously thought to be unique to complex brains, have much earlier evolutionary origins." A research paper by Lowe, graduate student Pani and collaborators was published this week in Nature.

The researchers say this discovery shows the need to consider that modern animals may have lost certain ancient processes and traits, and that biologists need to cast a wide net – including under-investigated and different-looking animals – in order to capture the entire evolutionary picture.

The research

As the brain develops in a vertebrate embryo, key genetic signaling centers lay the chemical foundation for brain development, like scaffolding for a building. Researchers previously thought that important elements of this scaffolding were exclusive to humans and other vertebrates, since they are absent elsewhere, even in close relatives of vertebrates.

In particular, most of the centers are lacking in a small, fishlike organism called amphioxus, commonly thought to be the best living example of the first chordates because they share many anatomical, developmental and genetic characteristics with vertebrates.

That absence led to the theory that several brain signaling centers evolved in early vertebrates in conjunction with more advanced parts of the brain, like the forebrain, the region responsible for higher thought processes. However, the Lowe lab's surprising finding shows that the scaffolding has much deeper roots in the tree of life – before humans, vertebrates and acorn worms – in a mysterious common ancestor.

More broadly, because vertebrates share these essential, hidden, brain-making processes with squirming, spineless acorn worms, biologists need to search beyond looks to find common genetic and evolutionary similarities.

Searching for vertebrate origins

From the earliest days of evolutionary biology, when Charles Darwin compared the beaks of Galapagos finches, scientists compared animals to each other by looking at sizes, shapes and arrangements of body parts.

Using those methods, many scientists theorized that amphioxus, also known as the lancelet, is a sort of living fossil that marks the transition from invertebrates to vertebrates. The small, fish-like lancelet looks more like vertebrates than any other invertebrate, sharing many anatomical similarities with vertebrates, including a central nervous system with a hollow nerve cord running down the back, a firm, supportive notochord beneath it, a true tail and segmented muscle blocks.

But anatomy is only part of the picture.

Over the past few decades, evolutionary biologists have capitalized on new biomedical technologies to peer beyond the surface of animals to the genetic "blueprints" that ultimately control the growth of anatomical structures. Using those tools, Lowe previously found that many important genes in acorn worm embryos were active in similar locations of the body as in mice and other vertebrates, despite their lack of anatomical similarities.

In this study, Lowe and Pani focused on brain origins – looking for the molecular signatures of three vertebrate brain-signaling centers. The signaling centers, like the scaffolding for a building, provide a framework for organizing proteins and cells.

The presence of these particular genetic signaling centers in a hemichordate was completely unexpected, based on previous studies from closer vertebrate relatives. These new results intriguingly indicate that amphioxus lost many of those genetic processes, even though it possesses a rather complex central nervous system more similar to vertebrates than hemichordates.

"No one thought hemichordates would be that informative in understanding the origin of vertebrates," Lowe said.

 "These findings remind us that modern animals are all at the 'tips of the branches' of the evolutionary tree," Lowe said. "And when we are searching for evidence about what our common ancestors were like, we have to look at all the branches to find the right clues."

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Cumi Kolosal Misteri Raksasa Bawah Laut

Bumi adalah planet yang di kelilingi oleh lautan, hampir dua pertiga bagian bumi adalah lautan dan hanya sepertiganya saja daratan. Banyak hal yang belum kita ketahui tentang lautan bahkan makhluk yang hidup di dasar laut masih menjadi tanda tanya besar bagi kita.

Salah satunya yaitu Cumi Kolosal, Apabila kita mengira Cumi raksasa sudah memiliki ukuran yang luar biasa maka perkenalkan makhluk yang satu ini, Colossal Squid atau Cumi kolosal.

Makhluk ini memiliki nama latin Mesonychoteuthis hamiltoni dan para ilmuwan percaya kalau makhluk ini bisa bertumbuh hingga paling tidak memiliki panjang 14 meter atau hingga mencapai 46 kaki. Ini membuatnya menjadi hewan invertebrata terpanjang di dunia. Faktanya mata hewan laut tersebut berukuran sebesar piring makan. Ini menjadi mata terbesar yang pernah ditemukan sebelumnya. Para ilmuwan meyakini hewan agresif ini mampu menyelam hingga kedalaman 6500 kaki. Walaupun demikian, para ilmuwan tidak bisa memastikan hingga seberapa panjang hewan ini bisa bertumbuh.

Mengenai Colossal Squid, Dr.Steve O'Shea, ahli cumi dari Auckland University berkata:

"Sekarang kita tahu kalau makhluk ini memiliki ukuran yang lebih besar dibanding Giant Squid. Giant Squid bukan lagi cumi terbesar di luar sana. Sekarang kita memiliki sesuatu yang lebih besar. Bahkan bukan cuma sekedar besar, tetapi benar-benar jauh lebih besar."

Colossal Squid di foto di atas ditangkap di Laut Ross dan memiliki panjang mantel 2,5 meter. Ukuran ini termasuk luar biasa karena Giant Squid terbesar yang diketahui hanya memiliki panjang mantel 2,25 meter. Lagipula, Colossal Squid di atas dipercaya masih dapat bertambah panjang hingga mencapai ukuran yang jauh lebih besar.

Teringat dengan legenda Kraken yaitu monster laut yang legendaris yang pernah terlihat di pesisir Norwegia dan iceland. Bedasarkan laporan dari pelaut, kraken adalah mahluk yang memiliki ukuran yang luar biasa yang bisa saja menyerang kapal. Dengan menjerat badan kapal dengan tentakelnya. Mungkin saat ini kraken disebut sebagai gurita raksasa. Legenda kraken bersumber dari laporan pelaut perancis dimana kapalnya diserang ketika kapal mereka sedang bertolak dari pesisir angola.

Bisa diduga penyebabnya adalah cumi kolosal. Masih banyak sekali tanda tanya mengenai cumi kolosal ini. Mungkin untuk suatu hari nanti kita bisa melihat hewan raksasa ini dengan mata kepala kita sendiri.

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Japanese Quake Gave Scientists An Unprecedented Look At A Big Tsunami

By many measures, the magnitude 9.0 earthquake that shook Japan a year ago was a record-breaker. It was the largest quake in the country’s written history, the trigger for the worst nuclear accident in 25 years and the costliest natural disaster ever.

Amid such superlatives, it’s easy to forget one more: During the Tohoku-oki quake, the seafloor off Japan’s coast wrenched itself farther apart than scientists had ever measured along any seafloor. In places, chunks of ground slipped horizontally past their neighbors by more than 50 meters and vertically by 10 meters.

“The earthquake was a scofflaw,” says Emile Okal, a geophysicist at Northwestern University in Evanston, Ill. “It violated the scaling laws we’re used to.”

That deviant behavior is what made the quake so deadly, by producing a monster tsunami. When the seafloor moves by half the length of a football field, it displaces an awful lot of water. Of the approximately 20,000 people who died on March 11, 2011, more than 90 percent drowned, were washed away or were otherwise killed by water. So researchers have been studying what happened off Japan’s coast, seeking ways to better detect a lawless quake, track the resulting tsunami and ultimately save lives.

Some of the work, based on survivor videos, reveals how quickly the deadly water surged into and then drained from coastal villages. Other research, looking at ancient sand deposits and boulders tossed like pebbles, suggests that Pacific-wide tsunamis like Tohoku-oki may be more common than once thought.

There’s some good news among the bad. The Japan tsunami was the earliest and best-detected monster wave ever, thanks to warning buoys set up globally after the 2004 Indian Ocean tsunami killed a quarter of a million people. With new findings from the Japan disaster and data from the global buoys, scientists in the United States are working to develop a forecast system that will in principle give people a better warning by predicting areas most likely to flood rather than the heights of incoming waves.

Still, one year after the Tohoku-oki disaster, scientists are far from taming the tsunami hazard. When it comes to translating scientific know-how into reducing death tolls from disasters, says Caltech seismologist Hiroo Kanamori, “we are always one step behind.”

In the wake

Many types of geological disturbances, including underwater landslides and volcanic eruptions, can trigger tsunamis. Most tsunamis, however, are set off by earthquakes, such as those that strike off the east coast of Japan. Here, the western part of the Pacific crustal plate dives beneath a tendril of the North American plate, building up strain that’s released occasionally in earthquakes.

Scientists and emergency planners in Japan are well aware of the tsunami threat; in June 1896, the Sanriku earthquake triggered a massive wave that killed more than 27,000 people. But the March 2011 disaster was simply off the scale compared with what most people would have expected.

The Tohoku-oki tsunami got so large not only because of the sheer amount of slip, but also because of the way the ground moved during the earthquake. When the quake hit, part of the seafloor that had been sloping down at a steep angle quickly lurched toward the surface, displacing an unprecedented amount of water, Takeshi Tsuji, a marine geologist at Kyoto University, said in San Francisco in December at a meeting of the American Geophysical Union.

Moments after the rupture came the first sign a tsunami was on its way. One Russian and three U.S. tsunami buoys nearby detected a huge movement of water, up to 1.64 meters high. “We knew immediately, within 30 minutes, that this was gigantic,” says Eddie Bernard, former director of the National Oceanic and Atmospheric Administration’s Pacific Marine Environmental Laboratory in Seattle.

Nowhere was the tsunami felt more dramatically than in the narrow inlets that riddle Japan’s Sanriku coast, north of the city of Sendai. Fishing villages nestle within the inlets where they are protected from wind and everyday waves, but such locations are the worst place to be when a tsunami arrives, says Costas Synolakis, a tsunami expert at the University of Southern California in Los Angeles and at the Hellenic Center for Marine Research in Anavyssos, Greece.

In the open ocean, a tsunami typically appears as a few extra centimeters or tens of centimeters moving atop the water column. But once the wave starts to approach land, the energy that had been spread over the entire ocean’s depth becomes squeezed into a shallow layer. This compression ramps up the tsunami’s amplitude as high as meters or tens of meters, especially in inlets that funnel the water forward. The Japanese waves reached as high as 40 meters.

At the fishing port of Kesennuma Bay, where nearly 1,500 people died, scientists have gone back to the scene of dramatic videos by two survivors to re-create what happened. Aware of the local risks, Kesennuma’s emergency manager had sent out a tsunami alarm within two minutes of the earthquake — before either the Japan Meteorological Agency or the Pacific Tsunami Warning Center, the national and international agencies in charge of similar alerts. Within 30 minutes the tsunami arrived at the port, swamping the bay.

In June, a team led by Hermann Fritz of the Georgia Institute of Technology’s Savannah campus used lasers to scan the surroundings where many survivors had clustered: a Coast Guard building, a vertical evacuation platform at the local fish market and a hill marked as an evacuation route. From the laser data and photos of the port, Fritz and his colleagues generated a photorealistic three-dimensional rendering of the landscape. The team then calibrated survivor videos against this data, mapping precisely how water inundated the bay and receded — information that’s impossible to obtain by surveying after the fact.

By measuring how current flowed on the water’s surface, the scientists calculated that soon after the tsunami reached its maximum height of 9 meters in the bay, it receded at unsurvivable speeds. The outflow sped up from 3 meters per second to 11 meters per second within just two minutes — something no one caught in the water could navigate through. “These currents are very important because they cause a lot of damage,” Fritz says.

When it comes to building concrete breakwaters, seawalls and other coastal defenses, Sanriku is perhaps the best-protected coastline in the world. Stone tablets left by past generations often mark the high-water point of historic floods. In some places, such long memories help plan prevention: The village of Otanabe was devastated by 15-meter-high waves during the 1896 tsunami, so residents rebuilt with a 15.5-meter-high seawall. In March 2011, the barrier kept the sea back. But overall, Sanriku’s coastal defenses were built to withstand a tsunami an order of magnitude smaller than the one that arrived. One much-ballyhooed breakwater in Kamaishi Bay, completed three years earlier at a cost of $1.6 billion, mostly crumbled in the face of the Tohoku-oki tsunami.

 Future forecasts

To help coastal residents better prepare, with or without concrete defenses, scientists are promoting new flooding forecasts instead of the usual reports of incoming wave heights. Few people inherently understand the concept of wave height, says Bernard: “They don’t know what a 3-meter or 6-meter tsunami means.” Another problem with wave-height forecasts is that coastlines are variable. A 1-meter tsunami might cause extensive flooding in one place, whereas a 3-meter tsunami that hits nearby might not lead to flooding at all.

Flooding forecasts could be particularly useful for countries that lie across an ocean basin from a massive quake, and hence have time to prepare for an oncoming wave. “An earthquake shakes for minutes, while a tsunami crashes for hours,” Bernard says.

In Hawaii, the aftereffects of the Tohoku-oki earthquake continued to arrive throughout the night. Because of the way the Hawaiian Islands are arranged, a tsunami can become trapped “and just keep banging around with no time for the water to drain,” Bernard says. The city of Kahului, on the north side of Maui, flooded extensively not just from the initial wave but also from the second and third that arrived soon thereafter. Emergency officials had evacuated much of the coastline, but fine-tuning computer programs used to predict the areas that will flood could mean less overall disruption, Bernard says.

New data to improve such forecasts come thanks to the network of ocean buoys designed for tsunami warnings, called the Deep-ocean Assessment and Reporting of Tsunamis, or DART, array. NOAA started using six of these buoys in 2001, and ramped up its investment after the 2004 Indian Ocean disaster. Today dozens of DART buoys, run by countries from the United States to Russia to Australia, operate constantly. In each, a recorder on the seafloor monitors the pressure of water passing overhead; a buoy tethered on the surface can instantly transmit warnings when a tsunami arrives.

The Tohoku-oki tsunami was the first to be measured by multiple DARTs right near where the quake happened, and was also the first mega-tsunami — with wave heights more than 1 meter in the open ocean — ever detected in real time. Data from the buoys are giving scientists confidence to push their tsunami forecasts into new realms, says Vasily Titov of the NOAA lab, such as cranking out local forecasts within one hour for U.S. coastlines or creating specialized forecasts for crucial facilities such as nuclear power plants, oil and gas infrastructure, and ports and harbors.

Following the Japanese tsunami, NOAA scientists tested their forecasting potential by taking wave-height data from buoys along the Japanese coast and simulating where current programs say the flooding should be expected. The resulting prediction map matched well with flooding actually observed, Titov says.

Titov has produced similar simulations for the U.S. Pacific Northwest coast, which is thought to be at high risk of a large earthquake and tsunami. After a magnitude 9.1 quake, Titov has calculated, wave heights could reach as high as 10 meters at some places along the Oregon and Washington coasts, such as near the mouth of the Columbia River or north of Coos Bay, Ore.

The bottleneck to warnings may not be technology but human organization, or lack thereof. A full-scale test in October of the new Indian Ocean tsunami warning system, set up explicitly to prevent a repeat of the death toll in 2004, went relatively smoothly. But some countries, such as Somalia, have not implemented national plans to respond and pass the message to local residents when an alert from the oceanwide system comes in.

Ring of Fire risk

Such warning systems may ultimately get more use in the Pacific than previously thought. “Paleotsunami” studies, which look for evidence of waves from centuries past, are beginning to show just how common these disasters are around the Pacific’s Ring of Fire.

Over the last decade, for instance, Japanese studies have revealed the scale of a tsunami that struck in July 869. An earthquake, probably around magnitude 8.6, sent sand and other debris flooding across the Sendai plain, Daisuke Sugawara of Tohoku University in Sendai said at the geophysics meeting. Eerily, these deposits match almost exactly the region that was inundated in March 2011.

Farther out in the Pacific, scientists are cobbling together the tsunami history of the small islands that dot the ocean’s vast expanses. In the Cook Islands, for instance, shells embedded into the sides of trees speak to the violent wave that swept over after a volcano erupted and collapsed cataclysmically near Vanuatu in the year 1452. Traces of the tsunami linger as high as 30 meters above sea level, yet tsunami assessments for the islands say residents there don’t need to worry about anything higher than 2.8 meters. “We are most definitely underestimating the hazard and risk,” James Goff, a tsunami expert at the University of New South Wales in Sydney, said at the geophysics meeting.

Other hints come from the traditional environmental knowledge of local residents. In New Zealand, 15th century Maori tales tell of people being thrown into the dunes by a nasty beast attacking from the sea. The tail of the beast broke off and became a small offshore island, a constant reminder of the ocean’s threat.

Past tsunamis may even have influenced how people settled islands across the Pacific. Early Polynesians had spread into the Samoan archipelago by 2,800 years ago but then stopped — quite possibly because that’s when a big tsunami washed across the Pacific. Similarly, the long-distance Pacific voyaging networks collapsed after the 15th century Vanuatu eruption, Goff said. At least three of four known massive Pacific tsunamis in the last 2,000 years coincided with big changes in human settlement, he said at the meeting.

For now at least, Japan seems to be recovering far more resiliently from its own wave disaster. Parts of the coast around the damaged Fukushima Daiichi nuclear reactors remain off-limits, but people have moved back into other areas to start rebuilding their lives. And government officials are already talking about one way to cope with the threat of future tsunamis.

Figuring the coast has gotten the worst it will get for quite some time, the minister for reconstruction suggested in January that the country should perhaps rebuild its concrete tsunami barriers — to the same height they were before.

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Bakteri Vampir Berpotensi Ciptakan Obat Antibiotik Terbaru

Bakteri yang banyak ditemukan dalam air limbah ini bisa merevolusi pengobatan modern. Bakteri ini pada dasarnya serupa dengan bakteri-bakteri pada umumnya tapi yang menjadikan bakteri ini berbeda dari bakteri yang lain yaitu cara bertahan hidupnya yang menghabiskan waktu dengan cara memburu bakteri lain dan mengisap semua nutrisinya. Itulah mengapa bakteri ini disebut sebagai bakteri vampir.

Bakteri tersebut bernama Micavibrio aeruginosavorus. Para ilmuwan telah mengetahui hal ini selama tiga puluh tahun terakhir, tapi terbukti sangat sulit untuk mempelajarinya dengan teknik konvensional. Peneliti dari Universitas Virginia baru saja berhasil memecahkan kode genetiknya kemudian mencari tahu cara kerja bakteri tersebut.

Micavibrio aeruginosavorus bertahan dengan menemukan strain bakteri lain. Ia kemudian menempel pada dinding sel mangsanya dan mulai menghisap nutrisi korban. Sebagian besar bakteri memang bertahan hidup dengan mengambil nutrisi dari lingkungan sekitarnya. Tapi bakteri Micavibrio aeruginosavorus hanya menggantungkan keselamatannya dengan cara menemukan dan menghancurkan bakteri lain.

Salah satu mangsa yang disukainya adalah musuh manusia, seperti Pseudomonas aeruginosavorus yang menyebabkan infeksi paru-paru serius pada pasien cystic fibrosis. Meskipun masih dini, para peneliti mengatakan bahwa akan ada kemungkinan untuk menggunakan Micavibrio aeruginosavorus melawan patogen yang mematikan. Tinggal menyuntikkannya ke area tubuh terdekat dengan sumber infeksi dan membiarkanya memburu dan menghancurkan bakteri menular.

bakteri vampir ini berpotensi mengurangi ketergantungan manusia pada antibiotik tradisional dan membantu mengurangi masalah resistensi obat yang sekarang dihadapi dunia medis.

Antibiotik yang pada umumnya bekerja dengan cara menghambat reproduksi bakteri atau menghancurkan dinding selnya. Masalahnya adalah bahwa strain bakteri tertentu telah kebal terhadap antibiotik tersebut dan menciptakan jenis baru yang disebut 'super bug'. Micavibrio aeruginosavorus merupakan alternatif menarik karena bakteri tidak dapat membangun ketahanan terhadap predator dengan cara yang sama seperti pada antibiotik tradisional.

Dan karena bakteri ini hanya memburu strain bakteri tertentu, maka tidak akan menimbulkan ancaman pada bakteri menguntungkan yang penting dalam tubuh manusia. Bakteri vampir ini juga bisa bekerja dalam lingkungan yang sulit, seperti pada lapisan lendir kental yang dibuat oleh Pseudomonas aeruginosavorus, dan menyerang target di mana antibiotik tradisional secara signifikan kurang efektif.

Namun tentu saja, bakteri ini belum siap disuntikkan ke dalam tubuh manusia. Masih dibutuhkan rekayasa genetik yang signifikan agar bakteri vampir ini dapat memburu strain bakteri yang diinginkan dan membiarkan bakteri yang lain. Meskipun demikian, penemuan ini berpotensi menjadi terobosan besar dan kenyataan bahwa ilmuwan sudah memiliki pemetaan gen adalah awal yang sangat menggembirakan bagi pengobatan medis dunia.

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Golongan Darah Manusia Dapat Berubah?

Semua yang ada di dunia ini memang bersifat dinamis, senantiasa berada dalam perubahan. Demikian juga halnya dengan golongan darah. Banyak kasus di dunia mengenai perubahan golongan darah yang terjadi. Ada yang mengalami perubahan golongan darah setelah melakukan donor organ. Berikut ini salah satu cerita mengenai perubahan golongan darah.

Sebuah kasus di Australia membuktikan bahwa hal itu benar adanya. Kisahnya berawal dari sebuah pasien wanita berusia 15 tahun, yang didiagnosis menderita penyakit liver. Kian hari tubuhnya kian menguning, yang menandakan semakin parahnya penyakit liver yang dideritanya. Sedangkan kita tahu bahwa liver mempunyai peranan yang penting dalam sistem metabolisme dalam tubuh kita. Jadi jika kegagalan organ liver yang diderita pasien itu dibiarkan terus terjadi, maka akan menyebabkan kematian. Tim dokter yang menangani pasien tersebut kemudian menyarankan transplantasi liver. Maka dilakukanlah upaya pencarian donor organ liver yang sesuai.

Setelah beberapa lama, akhirnya tim dokter menemukan donor liver. Namun yang menjadi kendala, terdapat perbedaan golongan darah antara golongan darah pasien dengan donor. Pasien mempunyai golongan darah O rhesus negatif, sedangkan donor mempunyai golongan darah O rhesus positif. Terdapat perbedaan rhesus antara pasien dan donor. Padahal diketahui bahwa jika ingin melakukan transplantasi organ, hendaknya dicari yang benar-benar sesuai guna meminimalisir reaksi penolakan organ donor pada tubuh sang pasien. Namun karena tidak ada pilihan lain dan mendesaknya waktu, akhirnya transplantasi itu dilakukan juga dengan setelahnya pasien diberikan obat-obatan untuk menekan reaksi penolakan. Biasanya pasien membutuhkan waktu sekitar 5 tahun mengonsumsi obat-obatan tersebut.

Sembilan bulan setelah transplantasi tersebut dengan mengonsumsi obat-obatan tersebut setiap hari, pasien kembali sakit dan memeriksakan diri ke dokter. Namun kali ini pasien sakit bukan karena livernya, karena setelah dilakukan pemeriksaan oleh tim dokter, keadaan liver sang pasien baik-baik saja. Ada hal yang mengejutkan dalam penemuan tim dokter, yaitu golongan darah pasien berubah menjadi O positif!! Tentunya hal ini sangat mengejutkan di dunia medis, sehingga tim dokter kembali melakukan pemeriksaan ulang dan pemeriksaan terhadap golongan darah orang tua pasien. Ternyata hasilnya memang benar, golongan darah pasien telah berubah.

Tim dokter kemudian melakukan pemantauan selama lima tahun. Dan setelah keadaan pasien benar-benar baik-baik saja, tim dokter kemudian baru berani menyatakan ke kalangan medis bahwa benar golongan darah seseorang dapat berubah.

Kejadian ini, bukan pertama kalinya di dunia. Bahkan di Indonesia sendiri pada tahun 2001 juga pernah terjadi perubahan golongan darah. Seorang pasien yang semula menderita penyakit anemia sehingga perlu melakukan transfusi darah, mempunyai golongan darah B. Setelah dilakukan transfusi darah, golongan darahnya berubah menjadi O. Namun kemudian pasien meninggal karena penyakitnya tersebut.

Kejadian perubahan golongan darah diduga karena terjadi perubahan dalam sumsum tulang yang memproduksi sel darah merah. Seperti halnya kasus yang terjadi pada pasien pertama, setelah menjalani transplantasi liver, tim dokter menduga sel-sel liver telah mempengaruhi sel-sel sumsum tulang dalam memproduksi sel darah merah.

Ternyata menurut medis memang golongan darah seseorang tidak bisa berubah. Namun golongan darah memungkinkan untuk berubah karena faktor tertentu. Seperti kelainan darah atau mengidap penyakit yang dapat merusak hemoglobin darah, contohnya: leukimia dan gagal ginjal. Benar atau tidaknya masih perlu mencari tau lebih jauh dan dibutuhkan penilitian medis dengan teknologi yang canggih.

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7 Kelebihan Indonesia Di Bandingkan Negara Lain

Meski kita selalu memandang negara kita sendiri, Indonesia dengan sebelah mata karena selalu merasa terpuruk di mata dunia atas, Indonesia tetaplah Tanah Air kita. Dan meskipun kini Indonesia dihiasi dengan maraknya ksi korupsi dan meningkatkannya kemiskinan, Indonesia tetaplah negara kita. Namun dibalik semua kekurangan Indonesia, negara ini adalah negara kaya akan hasil alamnya yang belum tentu negara maju memilikinya.

Berikut ini 7 kelebihan Indonesia yang tidak dimiliki oleh negara-negara maju lainnya :

1. Tambang Emas

Indonesia mempunyai tambang emas terbesar dengan kualitas terbaik di dunia yang diolah oleh PT Freeport. Mulai awal hingga kini pertambangan ini telah mengasilkan 7,3 JUTA ton tembaga dan 724,7 JUTA ton emas, atau setara dengan Rp.217.410.000.000.000.000.000 Rupiah. Namun sayangnya tambang ini dikelola oleh Amerika, dengan  prosentase keuntungangan 1% untuk Indonesia, dan 99% untuk Amerika sebagai pemilik teknologi. Dan jika lapisan tambang emas dan tembaga mulai menipis hingga kedalaman 400 meter, ternyata terdapat kandungan mineral yang harganya 100 kali lebih mahal dari pada emas yaitu uranium.

2. Cadangan Gas Alam Terbesar

Indonesia mempunyai cadangan gas alam terbesar didunia, yang terletak di Blok Natuna sebanyak 202 triliun kaki kubik dan masih banyak Blok-Blok penghasil tambang dan minyak seperti Blok Cepu dll. Dan masih dikelola oleh perusahaan asing Exxon Mobil dibantu Pertamina.

3. Hutan Tropis

Hutan tropis di Indonesia adalah yang terbesar di dunia dengan luas 39.549.447 Hektar, dan keanekaragaman hayati serta plasmanutfah terlengkap di dunia, yang terletak di pulau Sumatra, Kalimantan dan Sulawesi.

4. Lautan Luas

Indonesia negara dengan lautan terluas di dunia, di kelilingi dua samudra yaitu Pasifik dan Hindia hingga tidak heran memiliki jutaan spesies ikan yang tidak dimiliki negara lain.

5. Penduduk Terbesar Ke 4

Indonesia tercatat sebagai negara dengan penduduk terpadat ke 4 di dunia.

6. Tanah Subur

Tanah subur di Indonesia dipengaruhi karena banyaknya gunung berapi yang aktif, terlebih lagi negara ini dilintasi garis katulistiwa yang banyak terdapat sinar matahari dan hujan. Jika dibandingkan dengan negara-negara timur tengah yang memiliki minyak yang sangat melimpah negara ini tentu saja jauh lebih kaya.

7. Pemandangan Eksotis

Negara ini punya pemandangan yang sangat eksotis dan lagi-lagi tak ada negara yang bisa menyamainya. dari puncak gunung hingga ke dasar laut bisa kita temui di negara ini.

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Lampu Lalin Bagi Penderita Buta Warna

Membedakan warna tentu jadi hambatan bagi orang-orang yang buta warna. Akibatnya, mereka seringkali mengalami kesulitan dalam membaca warna lampu lalu lintas (lalin).

Hal ini menginspirasi Taro Ochiai, seorang profesor di Kyushu Sangyo University untuk menciptakan lampu lalu lintas bagi orang buta warna di Fukuoka, Jepang. Dilansir dari Telegraph, Selasa 8 Februari 2012, lampu  tersebut juga akan diuji coba selama satu bulan di Tokyo sebelum akhir Februari.

Dengan cepat, para pengendara buta warna akan mengenali tanda X merah muda yang dibenamkan dalam lampu merah. Mereka juga akan dengan mudah mengenali tanda X biru yang dibenamkan dalam lampu hijau, yang dalam penglihatan mereka menjadi berwarna kuning.

Penelitian menunjukkan, kedua tanda X itu terlihat jelas, bahkan dari kejauhan. Sementara, pengendara dengan mata normal tidak akan terlalu memperhatikan tanda X.

Sejak dioda pemancar cahaya mulai marak digunakan sebagai alternatif bola lampu biasa pada lampu lalu lintas, Ochiai pun mulai meneliti penggunaannya pada 2003. Menurutnya, para pengendara buta warna kesulitan melihat lampu lalu lintas biasa yang menggunakan kecerahan sebagai indikator.

Lampu lalu lintas buatan Ochiai ini, memenangkan penghargaan Good Design Award 2011 untuk perlengkapan dan fasilitas publik. Melihat kesuksesan ujicobanya di Fukuoka, Ochiai yakin lampu lalu lintas semacam ini bisa lebih banyak digunakan.

Di seluruh dunia, sebanyak delapan persen populasi pria dan 0,5 persen wanita memiliki kondisi buta warna. Dalam sebagian besar kasus, warna merah dan hijaulah yang paling sulit dibedakan.

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