2. Over the days of the Fukushima crisis, attention has switched from reactor building 1 to 3, to 2, back to 3 - and now, to 4. Here, it is not the actual reactor that is causing concern. Instead, it is a pool storing fuel rods that had been taken out of the reactor when it was shut down for maintenance before the earthquake struck. There have been reports that water levels were low; and now the US Nuclear Regulatory Commission (NRC), which has a team of experts advising in Japan, says the pool is completely dry. This means the fuel rods are exposed to the air. Without water, they will get much hotter, allowing radioactive material to escape - and the NRC says radiation levels are probably extremely high, creating a danger to workers at the plant. The company operating the plant has even warned of "re-criticality" - that a nuclear chain reaction could start among fuel rods in the now dry pool. That would not cause a nuclear explosion but it would increase the release of radioactive substances. Fukushima Daiichi: What went wrong * Reactor 1: Was first to be rocked an explosion on Saturday; fuel rods reportedly 70% damaged * Reactor 2: There are fears a blast on Tuesday breached a containment system; fuel rods reportedly 33% damaged * Reactor 3: Explosion on Monday; smoke or steam seen rising on Wednesday; damage to roof and possibly also to a containment system * Reactor 4: Hit by a major blaze on Tuesday and another fire on Wednesday JAPAN 2011-MARCH 16 – alarm over Japan atomic crisis About 450,000 people have been staying in temporary shelters, many sleeping on the floor of school gymnasiums. More than 4,300 people are listed as dead but it is feared the total death toll from the catastrophe, which pulverised the country's north-east coast, will rise substantially.

3. Emperor Akihito went on live TV on Wednesday to make his first public comments on the disaster, and urged an all-out rescue effort. TV stations interrupted programming to show the emperor describing the crisis facing the nation as "unprecedented in scale". The 77-year-old - deeply respected by many Japanese - said: "I hope from the bottom of my heart that the people will, hand in hand, treat each other with compassion and overcome these difficult times." - he said he was praying for the people's safety, and expressed his deep concern about the escalating nuclear crisis.

4. People watch a television broadcasting Japan's Emperor Akihito's televised address to the nation at an electronics retail store in Tokyo March 16. Japanese Emperor Akihito said on Wednesday that problems at Japan's nuclear-power reactors were unpredictable and he was "deeply worried" following an earthquake he described as "unprecedented in scale". It was an extraordinarily rare appearance by the emperor and his first public comments since last week's devastating earthquake and tsunami that killed thousands of people. (Issei Kato/Reuters)

5. Damage at Fukushima Dai-ichi nuclear plant, 150 miles north of Tokyo, is seen in this satellite image taken 9:35 a.m. local time on March 16. - Reuters

6. A picture released from Tokyo Electric Power Co. (TEPCO) on March 16 shows the damaged third (left) and fourth reactors of the Fukushima Dai-ichi power plant. - Tepco / AFP - Getty Images

7. Tepco / AFP - Getty Images - This handout picture, released from Tokyo Electric Power Co (TEPCO) on March 16, 2011 shows damaged third (L) and fourth reactors of the TEPCO Fukushima No.1 power plant in Fukushima north of Tokyo. A fresh fire broke out at the quake-hit Japanese atomic power plant in Fukushima early on March 16, compounding Japan's nuclear crisis following the March 11 earthquake and tsunami disaster.

8. Fukushima, Japan — Disaster response workers. A fresh explosion rocked a stricken nuclear power plant Tuesday and some workers were ordered to leave the PHOTOGRAPH BY: YURIKO NAKAO / Reuters

9. Heavy snow falls on rubble and rescue workers at a devastated factory area hit by an earthquake and tsunami in Sendai, northern Japan March 16, 2011. (REUTERS/Kim Kyung-Hoon)

10. Rescue workers walk past a damaged car during heavy snowfall at a factory area devastated by an earthquake and tsunami in Sendai, northern Japan March 16, 2011. REUTERS/Kim Kyung-Hoon

11. Rescue workers walk past a destroyed car during heavy snowfall at a factory area devastated by an earthquake and tsunami in Sendai, northern Japan March 16, 2011. REUTERS/Kim Kyung-Hoon

12. A member of a British search and rescue team looks out from the window of a damaged house surrounded by debris from the tsunami, as snow falls in Kamaishi, Japan, Wednesday, March 16, 2011. Two search and rescue teams from the U.S. and a team from the U.K. with combined numbers of around 220 personnel searched the town for survivors Wednesday to help in the aftermath of Friday's earthquake and tsunami. (AP Photo/Matt Dunham)

13. Germany’s Rapid Deployment Unit Urban Search and Rescue team arrives at Misawa Air Base in this U.S. Air Force handout photo dated March 16, 2011. International search and rescue teams are in Japan in response to the magnitude 9.0 magnitude earthquake and subsequent tsunami. REUTERS/US Air Force Tech. Sgt. Russell J. McBride/Handout

14. A youngster rests in a school gymnasium being used as a center for people to stay at whose homes were damaged by the tsunami in Ofunato, Japan, Wednesday, March 16, 2011. Matt Dunham / AP

15. People look on as they wait to be scanned for radiation at a temporary scanning center for residents living close to the quake-damaged Fukushima Dai-ichi nuclear power plant Wednesday, March 16, 2011, in Koriyama, Fukushima Prefecture, Japan. ( Gregory Bull / AP

16. Tsunami survivors' notes seeking information about their missing relatives and friends put up on the entrance of Natori City Hall in Natori, Miyagi Prefecture, northern Japan, Wednesday, March 16, 2011 five days after the disaster. Koji Sasahara / AP

17. People stay close to the heater at a shelter at Yamada town in Iwate prefecture on March 16, 2011. Str / AFP/ Getty Images

18. People queue up in front of a gas station in Mito, north of Tokyo Wednesday morning, March 16, 2011, following Friday's massive earthquake and tsunami. Kyodo News / AP

19. Police officers carry the body of a victim at Friday's earthquake and tsunami devastated area Wednesday March 16, 2011, in Rikuzentakata, Miyagi, northern Japan. Kyodo News / AP

20. Japan Self-Defense Force's members clear debris in Ofunato, Iwate, northern Japan Wednesday, March 16, 2011 after Friday's massive earthquake and tsunami. Kyodo News / AP

21. Ships are left aground among destroyed houses in Kesennuma, Miyagi Prefecture, Wednesday, March 16, 2011, five days after an earthquake-triggered tsunami devastated northeastern Japan. KYDPL / AP

22. A member of a British search and rescue team climbs on the roof of a building damaged by the tsunami, while searching for trapped people as snow falls in Kamaishi, Japan, Wednesday, March 16, 2011. Matt Dunham / AP

23. A member of the US Fairfax County search and rescue team from Virginia helps a colleague slide into a crawl space in a destroyed house to look for survivors in Kamaishi on March 16, 2011, four days after the devasting earthquake and ensuing tsunami on March 11. Nicholas Kamm / AFP/ Getty Images

24. A construction laborer controls the traffic at a devastated area in Kesennuma, Miyagi Prefecture, northern Japan, Wednesday, March 16, 2011. Shizuo Kambayashi / AP

25. The 4,724-ton freighter "M.V. Asia Symphony" lies on a pier after being hit by the tsunami, at the port in Kamaishi city, Iwate prefecture on March 16, 2011. Toshifumi Kitamura / AFP/ Getty Images

26. Self-Defense Force members put a tarp over bodies in Minamisanriku, northern Japan, Wednesday, March 16, 2011. Tsuyoshi Matsumoto / AP

27. Sendai, Japan — Hundreds of people wait in a line at the Ito-Yokado supermarket Tuesday morning. Some had waited five hours for the store's first opening in two days. Many of those in line said they were hungry and out of food and water. PHOTOGRAPH BY: Brian van der Brug / Los Angeles Times

28. Sendai, Japan — Hundreds of people line the street, waiting for a supermarket to open. Food and water are scarce in Sendai and the electricity remains off.PHOTOGRAPH BY: Carolyn Cole / Los Angeles Times

29. Gregory Bull / AP A woman holds her dog as they are scanned for radiation at a temporary scanning center for residents living close to the quake-damaged Fukushima Dai-ichi nuclear power plant on Wednesday, March 16, in Koriyama, Fukushima Prefecture, Japan.

30. Asahi Shimbun via EPA - Medical staff use a geiger counter to screen a woman for possible radiation exposure at a public welfare centre in Hitachi City, Ibaraki on March 16, after she evacuated from an area within 20km (12.4 miles) radius of the Fukushima Dai-ichi nuclear plant. The woman tested negative for radiation exposure.

31. Diego Azubel / EPA - A young girl wearing a face mask, followed by her family, boards the bullet train (Shinkansen) in Tokyo station on March 16. Radiation fears and the threat of another earthquake have prompted people to leave Tokyo by any means possible. Despite Japan's reassurance of radiation levels being below hazardous, several airlines have stopped flights into Tokyo and a number of companies are evacuating foreign nationals.

32. Adam Pretty / Getty Images Tokyo residents cram into the Shinkansen (Bullet Train) as they leave Tokyo heading west on March 16.

33. Survivors keep warm under covers in a school gymnasium being used as a shelter in Ofunato, Japan - Matt Dunham / AP

34. People retrieve gasoline from a car damaged by the tsunami in Minamisanrikucho in Miyagi prefecture. - AP

35. People wanting to leave Tokyo wait to enter the Immigration Bureau of Japan on March 16 in Tokyo. - Xinhua / Getty Images Contributor

36. Evacuees from the west side of Fukushima receive radiation scans in Nihonmatsu city in Fukushima prefecture, March 16. - Go Takayama / AFP - Getty Images

37. A family wearing face masks prepares to leave Tokyo on the Shinkansen bullet train at Tokyo station on March 16. Nuclear radiation fears and the threat of another earthquake have prompted many mothers with young children to leave Tokyo by any means possible. Despite Japan's reassurance of radiation levels being below hazardous, several airlines have stopped flights into Tokyo and a number of companies are evacuating foreign nationals. - Everett Kennedy Brown / EPA

38. An official in a radiation protection suit scans an evacuated woman and her dog with a Geiger counter in Koriyama city in Fukushima prefecture on March 16 - Ken Shimizu / AFP - Getty Images

39. Youths carry a woman from a shelter in Miyako, northern Japan on March 16. - Naoya Masuda / AP

40. A boy waits for boiled water to cook instant noodles outside a shelter in Sendai, in Miyagi prefecture on March 16. - AFP - Getty Images

41. Women react after they were reunited in Onagawa, Miyagi, on March 16. - AP

42. Police officers carry the body of a victim in Rikuzentakata, Miyagi on March 16. - AP

43. Rescue workers carry a charred body from the rubble onto a truck from a village destroyed by the devastating earthquake, fires and tsunami March 16, 2011 in Kesennuma, Miyagi province, Japan. (Paula Bronstein/Getty Images)

44. Two bodies are left covered in blankets in the devastated town of Rikuzenmaeda in the Iwate prefecture of Japan, March 16. - Shiho Fukada / Redux Pictures

45. Yamada, Japan — Headlights illuminate a disaster area. The official toll of the dead and missing following the devastating earthquake and tsunami that flattened Japan's northeast coast has topped 11,000, with 3,676 confirmed dead. PHOTOGRAPH BY: AFP / Getty Images

46. Fukushima, Japan — Teams of government specialists at emergency rescue headquarters analyze data on the leaked radiation from the nuclear complex damaged by last week's earthquake. PHOTOGRAPH BY: Wally Santana / Associated Press

47. Natori, Japan — Japanese Self-Defense Force soldiers look for victims amid the debris. Japan's Emperor Akihito delivered a rare address to a jittery nation in dread of a nuclear catastrophe. PHOTOGRAPH BY: TORU YAMANAKA / AFP / Getty Images

48. Kamaishi, Japan — Members of the Japan Self Defense Force walk through snow-covered ruins. PHOTOGRAPH BY: DAMIR SAGOLJ / Reuters

49. Minami-Sanriku, Japan — Crews in the coastal town of Minami-Sanriku search for victims Monday. PHOTOGRAPH BY: Brian van der Brug / Los Angeles Times

50. Ishinomaki, Japan — The Japanese town of Ishinomaki is flooded and the city's downtown area remains deserted. PHOTOGRAPH BY: Brian van der Brug / Los Angeles Times

51. Kesennuma, Japan — An elderly Japanese woman covers her face in reaction to learning her house was swept away by the tsunami. PHOTOGRAPH BY: KIMIMASA MAYAMA / EPA

52. A woman cries as she holds the hand of her dead mother buried in mud after an earthquake and a tsunami in Rikuzentakata City, Iwate Prefecture, northeastern Japan March 16, 2011. (REUTERS/Kyodo

53. Fukushima, Japan — Japanese medical personnel check a child for radiation exposure. PHOTOGRAPH BY: ASAHI SHIMBUN / EPA

54. Sendai, Japan — Hundreds of people line up to wait for food at a large supermarket. Some had been waiting four hours for the store to open. PHOTOGRAPH BY: Carolyn Cole / Los Angeles Times

55. Ofunato, Japan — Members of the Chinese International Search and Rescue Team search for victims inside a ruined house. PHOTOGRAPH BY: Lui Siu Wai / Associated Press

56. Minamisanriku, Japan — Rescue workers search for missing people. PHOTOGRAPH BY: JIJI PRESS / AFP / Getty Images

57. Minamisanriku, Japan — Residents eat emergency rations in a candle-lit shelter. PHOTOGRAPH BY: KAZUHIRO NOGI / AFP / Getty Images

58. A man looks on at a shelter for those displaced by the earthquake Wednesday, March 16, 2011, in Koriyama, Japan. (AP Photo/Gregory Bull)

59. Policemen gather around the covered bodies of victims retrieved from the debris in Rikuzentakata, Iwate Prefecture, days after the area was devastated by a magnitude 9.0 earthquake and tsunami, March 16, 2011. (REUTERS/Adrees Latif)

60. Earthquake victims read newspapers around a fire in Otsuchi, northern Japan Wednesday, March 16, 2011, after Friday's massive earthquake and tsunami. (AP Photo/Yomiuri Shimbun, Yoichi Hayashi)

61. A resident walks in an area damaged by tsunami as the debris among the trees shows the height of the tsunami at a village in Minamisanriku Town, Miyagi Prefecture in northern Japan on March 16, 2011. (REUTERS/Jo Yong-Hak)

62. Heavy snow falls as members of the Japan Self-Defense Force arrive at the devastated residential area in Otsuchi March 16, 2011. (REUTERS/Damir Sagolj)

63. A man holds his dog as they wait to be scanned for radiation exposure at a temporary scanning center for residents living close to the quake-damaged Fukushima Dai-ichi nuclear power plant Wednesday, March 16, 2011, in Koriyama, Fukushima Prefecture, Japan. (AP Photo/Gregory Bull)

64. Medical staff use a Geiger counter to screen a photographer for possible radiation exposure at a public welfare center in Niigata, northern Japan March 16, 2011. Radiation has been released into the atmosphere at the Fukushima Daiichi nuclear plant run by Tokyo Electric Power Co. on the country's northeast coast, which was badly damaged after a massive earthquake and tsunami on March 11. (REUTERS/Yuriko Nakao)

65. A woman walks away from a message wall after writing a message to the victims of last week's earthquake and tsunami in Japan in central Seoul, South Korea on March 16, 2011. (REUTERS/Truth Leem)

66. Yukie Ito (left), tries to comfort her daughter Hana, 8, with grandmother Tamiyo at a cold refugee center for the homeless March 16 in Kesennuma, Miyagi province. (Paula Bronstein/Getty Images)

67. Yukie Ito (left) tries to comfort her daughter Hana, 8, at a cold refugee center for the homeless March 16, 2011 in Kesennuma, Miyagi province, Japan. (Paula Bronstein/Getty Images

68. Rishiko reacts after visiting her home in the rubble of a village destroyed by the devastating earthquake and tsunami March 16 in Kesennuma, Miyagi province. (Paula Bronstein/Getty Images

69. An elderly man and woman push a cart carrying their salvaged belongings in Miyako, in Iwate prefecture, on March 16. (Takashi Noguchi/AFP/Getty Images)

70. A Filipino freighter crew sits in a shelter in Kamaishi city, Iwate prefecture on March 16. Their ship M.V. Asia Symphony (previous picture) was carried onto the pier after being hit by the tsunami. (Toshifumi Kitamura/AFP/Getty Images)

71. Japanese Defense Force members load tsunami relief goods at the port in Kamaishi city, Iwate prefecture on March 16. (Toshifumi Kitamura/AFP/Getty Images

72. Japanese Self Defence Force soldiers search for people missing from the March 11 earthquake and tsunami in a river bed in Miyako in Iwate prefecture on March 16. (Takashi Noguchi/AFP/Getty Images)

73. A survivor warms himself by a fire at an emergency shelter in Otsuchi March 16. In the fishing town of Otsuchi in Iwate prefecture, 12,000 out of a population of 15,000 have disappeared following Friday's massive earthquake and tsunami. (Damir Sagolj/Reuters)

74. People crowd a long-distance bus terminal in front of Sendai Railway Station to leave the earthquake and tsunami-hit town of Sendai, Miyagi Prefecture, on March 16. Railway services have been cancelled since the earthquakes around the area. (Toru Yamanaka/AFP/Getty Images)

75. A damaged replica of the Statue of Liberty stands next to tsunami damaged buildings, at Ishinomaki in Miyagi prefecture on March 15, 2011. (KIM JAE-HWAN/AFP/Getty Images)

76. Evacuees stretch while doing exercise at a makeshift shelter in Minamisanriku, northern Japan, Tuesday, March 15, 2011. (AP Photo/The Yomiuri Shimbun, Tsuyoshi Matsumoto)

77. Kiyomi Kimura (right) hugs her daughter Manami Numakura after Numakura found her mother at a shelter in the city of Ishinomaki in Miyagi prefecture on March 15, 2011. (JIJI PRESS/AFP/Getty Images)

78. A couple walks under falling snow amongst the rubble in Yamada, Iwate prefecture.march 15 - Jiji Press / AFP - Getty Images

79. Soldiers and a rescue worker carry the body of a resident through Kesennuma City on Tuesday.march 15 - Adrees Latif / Reuters

80. A baby is tested for radiation in Nihonmatsu, Fukushima prefecture, in northern Japan. - march 15 - Kyodo via Reuters

81. Rescuers and victims carry out bags of food aid from a helicopter in Yamada, northern Japan, on Tuesday.march 15 - Takashi Ozaki / AP

82. A member of a British search and rescue team searches for trapped survivors in the cab of a truck bowled over by the tsunami in Ofunato, on Tuesday. Two search and rescue teams from the U.S. and a team from the U.K. with combined numbers of around 220 personnel, searched for trapped survivors.MARCH 15 - Matt Dunham / AP

83. Earthquake survivor is rescued after being buried for four days Asahi Shimbun via EPA Japanese relief workers rescue a man who survived being buried for four days in the tsunami devastated remains of Ishimaki town, Iwate prefecture, Japan on March 15.

84. Kenji Konoha / AP School children greet each other as they gather to confirm their safety at a school in Miyako, northeastern Japan on March 15.

85. Debris left from the tsunami covers the entire seaside area of the devastated city of Ofunato, Iwate prefecture on March 15, 2011 as the country struggles to cope following the March 11 earthquake and tsunami disasters. Toshifumi Kitamura / AFP/ Getty Images

86. Lee Jae-Won / Reuters A woman, second right, is reunited with her relatives for the first time at a shelter in Rikuzentakata in Iwate prefecture, northeast Japan on March 15.

87. A rescue worker stands on top of a burned vehicle looking for more bodies amid the rubble of Kesennuma, Miyagi prefecture, Japan. - Paula Bronstein / Getty Images

88. A U.S. rescue team sniffer dog from Virginia searches the wreckage of a house during rescue operations in the city of Ofunato, Iwate prefecture.MARCH 15 - Toshifumi Kitamura / AFP - Getty Images

89. Bodies found in the ruins of the devastated residential area of Otsuchi are collected in a sports hall, Tuesday. In the fishing town of Otsuchi, 12,000 out of a population of 15,000 have disappeared.MARCH 15 - Damir Sagolj / Reuters

90. Ishinomaki JPN — Tsunami survivors cook and eat in front of their damaged home. PHOTOGRAPH BY: Associated Press

91. Japan Self-Defense Force officers prepare for a clean-up at a radiation affected area in Nihonmatsu, Fukushima prefecture in northern Japan, Tuesday. Panic swept Tokyo after a rise in radioactive levels around a nuclear power plant north of the city, causing some to leave the capital or stock up on food and supplies. – MARCH 15 Kyodo News via Reuters

92. People watch Japanese Prime Minister Naoto Kan on TV in a live broadcast at an evacuation center at Kawamata, northeastern Japan on Tuesday. In a nationally televised statement, Kan said radiation has spread from the three reactors of the Fukushima Dai-ichi nuclear plant in one of the hardest-hit provinces in Friday's 9.0-magnitude earthquake and the ensuing tsunami.march 15 - AP

93. Kesennuma, Japan — At an evacuation center, women wail after hearing about the death of family members. PHOTOGRAPH BY: Associated Press

94. A group of South Korean rescue workers and local policemen pay respect after collecting the body of a Japanese earthquake victim in tsunami-swept Sendai, Miayagi Prefecture on Tuesday.MARCH 15 - Yonhap via EPA

95. A food factory employee packs rice-balls into boxes to send to quake survivors in Akita city on Tuesday.MARCH 15 - / AFP - Getty Images

96. Neena Sasaki, 5, carries some of the family belongings from her home that was destroyed after the devastating earthquake and tsunami on March 15, 2011 in Rikuzentakata, Miyagi province, Japan. Paula Bronstein / Getty Images

97. A young Japanese survivor of the earthquake and tsunami searches her family home for any belongings she can find in the leveled city of Minamisanriku, in northeastern Japan, Tuesday March 15, 2011. David Guttenfelder / AP

98. Keijo Nakamura, right, and his wife Haruka react as they stand on the remains of a dead relative's home after the house was washed away by the tsunami in Ofunato, Japan, Tuesday, March 15, 2011. Matt Dunham / AP

99. A truck dangles from a collapsed bridge in Ishinomaki, northern Japan, Tuesday, March 15, 2011, four days after a powerful earthquake-triggered tsunami hit the country's east coast. (AP Photo/The Yomiuri Shimbun, Hiroshi Adachi

100. Bodies of victims are seen partly covered at a village destroyed by the earthquake and tsunami in Rikuzentakata in Iwate prefecture, northeast Japan on March 15, 2011. (REUTERS/Toru Hanai)

101. Richi Shida, right, and younger brother Kento try to open their chest of drawers at Ofunato, Iwate Prefecture, northern Japan, Tuesday, March 15, 2011. Shizuo Kambayashi / AP

102. Local men try to break open a safe they said washed away from their restaurant in Ofunato, Japan, Tuesday, March 15, 2011. Matt Dunham / AP

103. British search and rescue workers search under a roof removed from a house for survivors of the tsunami in Ofunato, Japan, Tuesday, March 15, 2011. Matt Dunham / AP

104. A man shops in a convenience store where shelves on food aisles are empty in Ofunato, Iwate Prefecture, northern Japan, Tuesday, March 15, 2011. Shizuo Kambayashi / AP

105. A woman wears layers of blankets and gloves to stay warm at a makeshift shelter at Ofunato, Iwate Prefecture, northern Japan, Tuesday, March 15, 2011. Shizuo Kambayashi / AP

106. A girl sits and curls up on chairs while staying at a makeshift shelter in Rikuzentakata, northern Japan, Tuesday, March 15, 2011. Kyodo News / AP

107. A boy waits in a line in front of a gas station in Kamaishi, northern Japan Monday, March 14, 2011 following Friday's massive earthquake and tsunami. Naoko Kawamura / AP

108. Civil defence relief workers stand together after an earthquake and tsunami swept through Otsuchi, in the Iwate prefecture, eastern Japan March 15, 2011. Otsuchi, situated on Japan's eastern coast, has ceased to exist, overwhelmed by a combination of earthquake, tsunami and fire that razed the town of 17,000 people on Friday, killing more than half the population in a matter of moments. The situation around the coastal town of Otsuchi was desperate, with people scavenging for food and rescue teams trying to put out forest fires, according to Patrick Fuller of the Red Cross international humanitarian group. REUTERS/International Red Cross/Handout

109. A South Korean rescue worker takes a rest besides a rescue dog as his team stops searching after the radioactive warning in an area hit by an earthquake and tsunami in Sendai, northeastern Japan March 15, 2011. Japan warned radioactive levels had become significantly higher around a quake-stricken nuclear power plant on Tuesday after explosions at two reactors, and the French embassy said a low level radioactive wind could reach Tokyo by the evening. REUTERS/Jo Yong-Hak

110. A woman (L) and her maternal aunt cry at a shelter as they reunite for the first time after an earthquake and tsunami in Rikuzentakata in Iwate prefecture, northeast Japan March 15, 2011. REUTERS/Lee Jae-Won

111. Japan Self-Defense Force officers wearing masks arrive at the devastated residential area of Otsuchi March 15, 2011. In the fishermen town of Otsuchi in Iwate prefecture, 12,000 out of a population of 15,000 have disappeared following last Friday's massive earthquake and tsunami. REUTERS/Damir Sagolj

112. Rescue workers search through rubble in an area hit by an earthquake and tsunami in Otsuchi March 15, 2011. (REUTERS/Aly Song)

113. A rescue helicopter lowers a man in search of victims along a remote hillside near Kesennuma City on March 15, 2011, days after the area was devastated by a magnitude 9.0 earthquake and tsunami. (REUTERS/Adrees Latif)

114. An injured survivor searches for food at a destroyed supermarket in the devastated residential area of Otsuchi March 15, 2011. In the fishermen town of Otsuchi in Iwate prefecture, 12,000 out of a population of 15,000 have disappeared following last Friday's massive earthquake and tsunami. REUTERS/Damir Sagolj

115. Two elderly couples greet each other at a shelter as they reunite after the earthquake and tsunami in Rikuzentakata in Iwate prefecture, northeast Japan March 15, 2011. REUTERS/Lee Jae-Won

116. People rest at a shelter for earthquake and tsunami evacuees in Miyako city in Iwate prefecture, northeast Japan March 15, 2011. REUTERS/Kyodo

117. People on their wheelchairs rest at an evacuation centre in Kesennuma, Miyagi Prefecture in northern Japan, after an earthquake and tsunami struck the area, March 15, 2011. REUTERS/Kyoo

118. A shopper looks at the empty shelves in a supermarket in Moriyama, Japan, Tuesday, March 15, 2011, four days after a giant quake and tsunami struck the country's northeastern coast. (AP Photo/Mark Baker)

119. Residents unload food and water from an HH-60H Sea Hawk helicopter assigned to the Black Knights of Helicopter Anti-Submarine Squadron (HS) 4 in Miyagi Prefecture, in this U.S. Navy handout photo dated March 15, 2011. The squadron is assisting in relief efforts following the magnitude 9.0 earthquake and tsunami. REUTERS/U.S. Navy/Mass Communication Specialist 3rd Class Alexander Tidd/Handout

120. President of the International Federation of Red Cross and Red Crescent Tadateru Konoe (C) walks among rescue workers searching through rubble in a residential area of tsunami-hit Otsuchi March 14, 2011. After my long career in the Red Cross where I have seen many disasters and catastrophes, this is the worst I have ever seen. Otsuchi reminds me of Osaka and Tokyo after the Second World War when everything was destroyed and flattened, Tadateru Konoe told Reuters during a visit to the coastal town. In the town of Otsuchi in Iwate prefecture, 12,000 out of a population of 15,000 have disappeared following Friday's massive earthquake and tsunami. REUTERS/Damir Sagolj

121. U.S. Air Force and Marine personnel look out over debris left at Sendai airport on March 13, 2011. (REUTERS/US Air Force/Staff Sgt. Samuel Morse)

122. A presentation by Nubia [email_address] http://nubiagroup-powerpoint-collection.blogspot.com/ http://groups.yahoo.com/group/Nubia_group_Powerpoint_Collection/