These are the ghostly particles that flood the cosmos but which are extremely hard to detect and study.

Experiments have now established that one particular type, known as the muon "flavour", can flip to the electron type during flight.

The observation is noteworthy because it allows for the possibility that neutrinos and their anti-particle versions might behave differently.

If that is the case, it could be an explanation for why there is so much more matter than antimatter in the Universe.

Theorists say the counterparts would have been created in equal amounts at the Big Bang, and should have annihilated each other unless there was some significant element of asymmetry in play.

"The fact that we have matter in the Universe means there have to be laws of physics that aren't in our Standard Model, and neutrinos are one place they might be," Prof Dave Wark, of the UK's Science and Technology Facilities Council (STFC) and Oxford University, told BBC News.

The confirmation that muon flavour neutrinos can flip, or oscillate, to the electron variety comes from T2K, an international collaboration involving some 500 scientists.

The team works on a huge experimental set-up that is split across two sites separated by almost 300km.

At one end is the Japan Proton Accelerator Research Centre (J-Parc) located on the country's east coast.

It generates a beam of muon neutrinos that it fires under the ground towards the Super-Kamiokande facility on the west coast.

The Super-K, as it is sometimes called, is a tank of 50,000 tonnes of ultra-pure water surrounded by sensitive optical detectors.

These photomultiplier tubes pick up the very rare, very faint flashes of light emitted when passing neutrinos interact with the water.

In experiments in early 2011, the team saw an excess of electron neutrinos turning up at Super-K, suggesting the muon types had indeed changed flavour en route.

But just as the collaboration was about to verify its findings, the Great Tohoku Earthquake damaged key pieces of equipment and took T2K offline.

Months of repairs followed before the project was able then to gather more statistics and show the muon-electron oscillation to be a formal discovery.

Details are being reported on Friday at theEuropean Physical Society Conference on High Energy Physics in Stockholm, Sweden.

"Up until now the oscillations have always been measured by watching the types disappear and then deducing that they had turned into another type. But in this instance, we observe muon neutrinos disappearing and we observe electron neutrinos arriving - and that's a first," said Prof Alfons Weber, another British collaborator on T2K from the STFC and Oxford.

Neutrino oscillations are governed by a matrix of three angles that can be thought of as the three axes of rotation in an aeroplane - roll, pitch and yaw.

Other research has already shown two of the matrix angles to have non-zero values. T2K's work confirms that the third angle - referred to as theta-one-three - also has to have a non-zero value.

This is critical because it allows for the oscillations of normal neutrinos and their anti-particles, anti-neutrinos, to be different - that they can have enough degrees of freedom to display an asymmetrical behaviour called charge parity (CP) violation.

CP-violation has already been observed in quarks, the elementary building blocks of the protons and neutrons that make up atoms, but it is a very small effect - too small to have driven the preference for matter over anti-matter after the Big Bang.

However, if neutrinos can also display the asymmetry - and especially if it was evident in the very massive neutrinos thought to have existed in the early Universe - this might help explain the matter-antimatter conundrum. The scientists must now go and look for it.

It is likely, though, that much more powerful neutrino laboratories than even T2K will be needed to investigate the issue.

"We have the idea for a Hyper-Kamiokande which will require an upgrade of the accelerator complex," Prof Weber told BBC News.

"And in America there's something called the LBNE, which again would have bigger detectors, more sensitive detectors and more intense beams, as well as a longer baseline to allow the neutrinos to travel further."

Erratic and extreme rainfall is causing catastrophic flooding, most recently in northwest India and Nepal following heavy rainfall in June.

But the sharing of hydrological data can be a sensitive issue because of disputes over water use.

Officials say a network is required to share data across borders.

Experts and officials told the BBC that countries in the region are doing very little to help each other forecast floods.

Referring to the event last month, Chiranjibi Adhikary, chief district officer of Darchula district in western Nepal, which shares a border with India's flood-hit Uttarakhand state, said: "We received no warning from the Indian side about that devastating flood."

The flooding in the Mahakali river that criss-crosses India and Nepal claimed more than 30 lives on the Nepalese side and swept away many buildings at the district headquarters Khalanga.

Nearly 1,000 people have been confirmed dead because of the floods in the Indian side while thousands are still missing.

"We are still trying to contact them [the Indian authorities] to know what was the reason behind the floods, but there has been no telephone contact yet," Mr Adhikary told the BBC.

In western South Asia, the Kabul river that straddles Afghanistan and Pakistan was a major contributor to the massive floods in the Pakistani territory in 2010.

But, officials say, there was no communication on flood-forecasting between the two countries then, nor is there any now.

"The Kabul river is of course a flood threat to us even today but still we have no hydrological and rainfall data exchange with Afghanistan," said Mohammad Riyaj, Pakistan's chief meteorologist.

"It is something we need to do with urgency but this can be done only at the policy-making level."

One of the worst flood-hit countries in the region, Bangladesh, receives relatively little hydrological data from upstream Nepal.

Officials at Nepal's Department of Hydrology and Meteorology said they used to send the information to Dhaka by fax before but now staffing constraints have become a problem.

Pakistan does have a mechanism to receive limited hydrological data from India but officials say it is quite inadequate for meaningful flood forecasting.

"For instance, the Indian side informs the Indus Water Commission (a body under an agreement between New Delhi and Islamabad on the sharing of Indus river water) only when the water level in the Chenab river crosses 75,000 cusecs," says Mr Riyaj.

"That gives us much less time for evacuation and preparation for floods."

The Chenab is a major tributary of the Indus river that originates in Tibet and flows through India into Pakistan.

India and Pakistan have deep running disagreements on the sharing of Indus waters and have been involved in litigation.

Mr Riyaj said hydrological information on tributaries of the Chenab, including the Jhelum, Ravi and Sutlej rivers, that flow in from India would also be of great help for timely flood forecasting.

Officials in Bangladesh, however, said there had been some progress on hydrological data sharing with India as they were now getting information from three reading stations for the Ganges and four for the Bramhaputra in the Indian side.

The chief of Bangladesh's flood warning office, Amirul Hossain, said his country was also getting Bramhaputra's hydrological data from Chinese authorities in Tibet, where the river originates.

"But since our people are demanding that they should get flood warnings at least a week in advance, we would like to get the hydrological data from a bit further off areas in India so that we get more lead time for a forecast," Mr Hossain said.

Officials say the data Bangladesh gets from India at present are from nearby border areas.

Hydrological data is quite a sensitive issue in India, especially between states that have been at loggerheads over the sharing of water resources for quite some time.

The recent order by India's water resources ministry to its authorities regarding the constitution of the "classified data release committee" read: "The committee shall consider requests for release of classified data after due verification by the concerned chief engineer of the Central Water Commission and [the] receipt of [a] secrecy undertaking."

Rajendra Sharma, who heads Nepal's flood forecasting division at the country's meteorological office, said: "For genuine regional flood forecasting, all countries including India and China will have to actively participate in the exchange of hydrological and meteorological data."

Indian officials said they recognised the importance of cross border cooperation for effective flood forecasting.

Though he was optimistic that things could improve in future, M Shashidhar Reddy, vice chairman of India's National Disaster Management Authority, said: "Things which are on paper sometimes do not get translated into action."

The Cassini probe, in orbit around the gas giant, is going to take a picture of Earth, and the imaging team wants everyone to wave and smile.

Because of the great distance to Saturn, our home will appear as a mere pixel in the final photo.

But Cassini scientist Carolyn Porco says it is a moment to "celebrate life on the Pale Blue Dot".

"Waving time" - the period when the spacecraft's cameras will be operating - starts at 21:27 GMT and ends at 21:42 GMT (22:27-22:42 BST).

These timings include the 80 minutes it will take reflected light from the surface of the Earth to travel the nearly 1.5 billion km (900 million miles) to reach the outer Solar System.

Dr Porco's Ciclops imaging team will be producing a large mosaic of Saturn and its ring system on Friday.

Earth will appear as small speck in the lower-right of the final picture.

It is likely to be several days before the first images are processed and released.

The probe snapped a similar mosaic in 2006. On that occasion, Earth was positioned in the upper-left of the frame.

But Dr Porco says the set-up six years ago was not ideal. For the re-shoot, she plans to use Cassini's highest resolution camera, and the most appropriate filters to capture Earth in natural colour.

More than that, however, she says, people on Earth will know this time they are on camera, and that offers everyone the opportunity to participate.

Dr Porco hopes the picture will be reminiscent of the famous "Pale Blue Dot" image captured by the Voyager-1 probe in 1990.

That was a picture she helped organise with the astronomer and popular science writer Carl Sagan.

He memorably described the Earth as looking like a "mote of dust suspended in a sunbeam", such was its apparent insignificance in the vastness of space.

Inspired in part by the Cassini team's plans, scientists working on the Messenger probe at Mercury will also be picturing Earth on Friday and Saturday.

Messenger will see Earth as it scans the skies for any previously unrecognised objects that might be circling the innermost world.

Timings for these pictures are 11:49, 12:38, and 13:41 (all GMT) on both Friday and Saturday.

Parts of the Earth not illuminated in the Cassini images, including all of Europe, the Middle East and Central Asia, will appear illuminated in the Messenger pictures.

More details on the Saturn project can be found at The Day The Earth Smiled website.

The companies want to be able to report regular statistics about the nature and scope of what data is being asked for.

Whistle-blower Edward Snowden's revelations about US spying capabilities has left the tech firms keen to assert their independence.

Authorities are said to be considering the companies' request.

"We just want to make sure we do it right," said Gen Keith Alexander, director of the National Security Agency.

"We don't impact anything ongoing with the FBI. I think that's the reasonable approach."

The companies sent a letter outlining their request on Thursday to Gen Alexander, as well as President Obama and Congress.

It was co-signed by some of the most influential companies in the tech world, including Facebook, Twitter and LinkedIn.

Campaign groups such as the Electronic Frontier Foundation and Human Rights Watch are also backing the action.

Companies are currently allowed to release limited data regarding security requests and their nature.

But as it stands those disclosures must be limited in scope, and in many cases require that the firms ask the courts for permission to make the information public.

Many users of popular services, particularly social networks, reacted angrily to the news that companies regularly make available information about users when requested to do so.

"They don't have a choice. Court order, they have to do this," Mr Alexander from the NSA said, suggesting that security authorities could be open to the idea.

"What they want is the rest of the world to know that we're not reading all of that email, so they want to give out the numbers.

"I think there's some logic in doing that."

It has launched a plan to update and co-ordinate national tax laws.

There was criticism in the UK earlier this year when it emerged that Google, Starbucks and Amazon paid little tax despite having big UK operations.

Following that criticism Starbucks agreed to pay more tax.

The OECD came up with the plan at the request of the G20 group of leading nations. Finance ministers from the G20 are meeting in Moscow.

OECD secretary-general Angel Gurria said: "International tax rules, many of them dating from the 1920s, ensure that businesses don't pay taxes in two countries - double taxation.

"This is laudable, but unfortunately these rules are now being abused to permit double non-taxation."

It is calling for greater international co-operation to close gaps that allows income to "disappear" for tax purposes.

The OECD also said that tax income should reflect the economic activity it generates.

That would address some of the criticism aimed at big companies.

Earlier this year, Google was fiercely criticised by UK MPs for routing £3.2bn of UK sales through Dublin and paying little tax as a result.

Starbucks has been questioned for transferring money to a Dutch sister company in royalty payments.

And Apple's chief executive Tim Cook was questioned by US lawmakers about the billions of dollars his company keeps in its Irish divisions.

The companies point out that these schemes are legal and they have a duty to their shareholders to minimise their tax bills.

Corporate responsibility

British Prime Minister David Cameron said he was "delighted" the OECD had produced the report.

"Taxpayers, governments and businesses all suffer when some companies manipulate the tax system to avoid paying their fair share of taxes," he said.

The OECD hopes its recommendations will be put into action over the next two years and is working on an international legal structure that would help countries introduce the new rules quickly.

"Multinationals still have not grasped that tax honesty is an integral part of corporate responsibility," said Florian Wettstein, professor of business ethics at the University of St. Gallen, based in Switzerland.

"As a result, the public increasingly perceives them as hypocritical and untrustworthy."

Campaigners say that aggressive tax policies are particularly hard on poorer nations, who need all the tax revenue they can generate.

ActionAid tax campaigns manager Chris Jordan said: "For the developing countries that lose billions of dollars each year to aggressive tax avoidance, the stakes couldn't be higher.

"It's vital that they have a seat at the table, so global tax rules aren't stitched up by the major powers."

More than 1,000 people protested outside the governing Popular Party (PP) headquarters in the capital.

There is widespread anger over allegations of illegal cash payments to members of the conservative PP.

Prime Minister Mariano Rajoy is under pressure to give an explanation to parliament. He denies wrongdoing.

The demonstrations on Thursday night caused disruption to traffic in central Madrid.

Protesters held placards calling on the government to resign. There was also a protest outside the PP offices in Valencia.

The corruption allegations coincide with Spain's worst economic crisis for decades, with record unemployment and many Spaniards struggling to make ends meet.

The PP's former treasurer, Luis Barcenas, is in custody facing trial for corruption and tax fraud. He denies the allegations.

He says he made numerous bonus payments - in cash - to Mr Rajoy and other senior party members, out of the party slush fund of illegal donations by businesses.

Ledgers detailing such payments, and apparently written by Mr Barcenas, have been published in two Spanish newspapers - El Pais and El Mundo.

Mr Rajoy and other PP members have repeatedly denied that they received illegal payments.

The prime minister has accused Mr Barcenas of blackmail.

For now at least there is no sign that Mr Rajoy might resign over the scandal, the BBC's Tom Burridge reports from Madrid. The PP has a comfortable majority in parliament.

Stem cells can become any other part of the body - from nerve to bone to skin - and are touted as the future of medicine.

Researchers in Japan will use the cells to attempt to treat a form of blindness - age-related macular degeneration.

The announcement was described as "a major step forward" for research in the field.

There are already trials taking place using stem cells taken from embryos. But this is ethically controversial and the cells will not match a patient's own tissues, so there is a risk of rejection.

Induced pluripotent stem cells, however, are made by coaxing a sample of the patient's skin to become stem cells, so there should be no risk of rejection.

Japan's health minister, Norihisa Tamura, has ruled that the cells can now be tested in patients.

The trial will by run by the Riken Center for Developmental Biology and the Institute of Biomedical Research and Innovation Hospital in Kobe.

Initially, six patients will receive transplants of cells to see if the procedure can restore their damaged vision.

Prof Chris Mason, an expert on regenerative medicine at University College London said: "This was expected, but it's obviously a major step forward.

"They are beneficial for two main reasons. One, they are from the patients themselves so the chance of rejection is greatly reduced and there are the ethical considerations - they do not have the baggage which comes with embryonic stem cells.

"On the down side we are a decade behind on the science. Induced pluripotent stem cells were discovered much later, so we're behind on the safety."

In 2012, Prof Shinya Yamanaka shared the Nobel prize for medicine or physiology for his discovery that adult human tissue could be coaxed back into a stem cell state.

Police allege the politician, Arsal Khan Khichi, hired a cook to poison food at his cousin's home last month.

Mr Khichi had lost to his cousin in a recently-held local election in Punjab.

However, police say his rival was not at home when the poisoning took place. Mr Khichi is thought to be in Dubai and has not commented on the allegations.

The BBC was unable to reach his family for comment.

Police believe the poisoning plot was the result of a political feud between two branches of the family.

They are questioning a cook, Mohammad Rafiq, who says he was paid to poison the food by Arsal Khichi.

"Cook Rafiq has confessed that he poisoned the food after getting 100,000 rupees [about $1,000] from Arsal Khichi," district police officer Vehari Sadiq Ali Dogar told BBC Urdu.

Police were seeking a warrant for the arrest of Arsal Khichi who had "escaped to Dubai on 15 July", he added.

"Arsal had gone to Dubai before the confession of the cook. He runs a business there, so we need to investigate if he was expecting this confession or he went overseas on a routine trip."

The poisoning in the town of Mailsi, about 70km (45 miles) south-east of Multan, took place on 9 June, police say.

It followed followed recent provincial elections in which Arsal Khan Khichi had lost to his cousin Jehanzaeb Khan Khichi, they add.

About 50 people fell ill after the meal, with 22 people dying.

Police say they waited until medical reports confirmed poisoning before they arrested the cook.

"If Arsal Khichi claims he is not involved in this case, he must come back, face the court and prove himself innocent," Jehanzaeb Khan Khichi told BBC Urdu.

Football's governing body Fifa announced that the cheapest ticket for overseas fans for the final on 13 July was $440 (£288) and the most expensive $990 (£650).

The tournament starts on 12 June next year, with the first game being played in Sao Paulo.

Tickets will go on sale from 20 August.

Fans have until 10 October to apply and a ballot will be held to decide which of these applications are successful.

Only later will tickets be sold on a first come, first served basis.

In total about three million tickets will be available for fans.

For Brazilian nationals the cheapest tickets start at $15. These are only available for students, those aged over 60 and people on social welfare programmes. For other Brazilians tickets start at $30.

The lowest price paid for a ticket in the 2010 World Cup in South Africa was $20, also for group stage matches in the special category set aside exclusively for residents.

The governing body had previously said that tickets in Brazil would be the "cheapest ever".

The Fifa ticket website will include a map of the ground that shows the location of different categories of tickets.

This meant there would be "no surprises" over where fans would end up sitting, said Fifa marketing director Thierry Weil, who is in charge of ticketing strategy.

Supporters can request a maximum of four seats per match, and for a maximum of seven matches.

He said there would be a reselling system run by Fifa, if people were unable to attend games for which they had bought tickets.

At least 400,000 tickets will be reserved exclusively for residents of Brazil, with about 50,000 for construction workers who were involved in building and upgrading the grounds for the tournament.

The news came as Mr Rudd set out an overhaul of asylum policy ahead of a general election expected shortly.

Australia has seen a sharp rise in the number of asylum-seekers arriving by boat in recent months.

Following the news, rioting reportedly broke out at an asylum centre in Nauru. It was unclear if there was a link.

"Police have been called in to help with a major disturbance at the asylum seeker detention centre on Nauru," the Australian Broadcasting Corporation (ABC) reported.

The cause of the disturbance, involving 150 detainees, had not been established, ABC added.

Mr Rudd had said the "hard-line decision" was taken to ensure border security. It was also aimed at dissuading people from making the dangerous journey to Australia by boat.

"Our country has had enough of people-smugglers exploiting asylum-seekers and seeing them drown on the high seas," he said.

'No chance'

The deal - called the Regional Settlement Arrangement - was signed by the Australian and PNG leaders on Friday.

Mr Rudd, who ousted Julia Gillard as Labor Party leader amid dismal polling figures last month, made the announcement in Brisbane flanked by PNG Prime Minister Peter O'Neill.

"From now on, any asylum-seeker who arrives in Australia by boat will have no chance of being settled in Australia as a refugee," Mr Rudd said.

Under the agreement, new arrivals will be sent to PNG - which is a signatory to the United Nations Refugees Convention - for assessment and settled there if found to be a refugee.

To accommodate the new arrivals, an offshore processing centre in PNG's Manus island will be significantly expanded to hold up to 3,000 people. No cap has been placed on the number of people Australia can send to PNG, Mr Rudd said.

"The new arrangements will allow Australia to help more people who are genuinely in need and help prevent people smugglers from abusing our system."

The rules would apply to all those arriving in Australia by boat from today, Immigration Minister Tony Burke said.

In return, Australia is to channel aid to PNG, including to a major regional hospital and the university sector, The Australian reported. No costs were disclosed in connection with the deal.

Boat arrivals have soared in the past 18 months, with most asylum seekers coming from Iraq, Iran, Sri Lanka, Afghanistan and Bangladesh. They make their way to Indonesia and from there head to Christmas Island, the closest part of Australian territory to Java.

They travel in boats that are often over-crowded and poorly-maintained. Several have sunk in recent months, killing passengers.

Last year, the Australian government reintroduced a controversial policy under which people arriving by boat in Australia are sent to camps in Nauru and Papua New Guinea for processing.

But the policy has so far failed to deter boat people, who are arriving in increasing numbers. It has also been strongly criticised - most recently by the UNHCR - for the conditions which asylum-seekers face at the camps.

Late on Thursday, Indonesia said it had agreed to stop giving Iranians visas on arrival as part of the measures to ease the problem.

'Turned its back'

Asylum has become a key election issue in Australia and polls must be called before the end of November.

Opposition leader Tony Abbott - whose party looked on course to trounce Labor at the polls before the leadership change - has said he will turn boats back to Indonesia when safe to do so.

Responding to this agreement he said: "While this certainly is a very promising development in offshore processing, it is about processing boat people, it's not about stopping the boats and that in the end is what we have to have."

Human rights advocate David Manne, meanwhile, said Australia had signed up to international conventions to protect "people who come to its shores, not exposing them to further risks elsewhere".

"The fact remains that Australia hosts only 0.3% of refugees worldwide and yet what we see here is a policy designed not only to deter asylum seekers from coming and seeking refuge in Australia, but one that also proposes to shift our responsibilities on to others," ABC quoted him as saying.

Rights group Amnesty International's regional refugee co-ordinator Graeme McGregor said the move would be marked "as the day Australia decided to turn its back on the world's most vulnerable people, closed the door and threw away the key".

As airports go, Kazakhstan's Almaty International has not much going for it. It's small, and there's not much to keep travellers entertained.

For Mohammed Al Bahish being stuck there for 120 days has been an excruciating ordeal.

He does not even have access to the duty free or the overpriced cafes.

The 26-year-old Palestinian refugee, born in Iraq, is confined to what officials call "the sterile zone" for travellers and airport staff - he's the only one who belongs in neither category.

He cannot enter Kazakhstan because he has no visa, but nor does he have a visa to enter any other country. Israel won't allow him to travel to the Palestinian territories, and the UN accepts that with no living relatives in Iraq, it would be unsafe for him to return to the country of his birth.

Every day he wakes up to the same monotonous female voice announcing flight details, gate closures and a lengthy monologue - regularly repeated - on Kazakh customs regulations.

"I feel like I am going slightly crazy," he says.

Already pale and puffy-faced, he is confined to a windowless 2m by 3m room inside the arrivals hall.

It reeks of cigarette smoke. There is a bunk bed, a shabby sofa, and a Koran on a table by the wall.

Through the door, which is slightly ajar, new arrivals stream past on their way from the landing gates to passport control.

Intensifying Mohammed's sensation of limbo, he is fed on meals prepared for passengers on Kazakhstan's national air carrier, Air Astana.

"They bring aeroplane food three times a day - tiny boxes of salad and cakes," he says. "For the entire month of June I ate beef and mushroom stroganoff. I don't think I will ever eat beef again."

Airport security controls his every movement outside the room. Occasional coffee runs to a drinks dispenser are permitted, as are visits to the showers used by staff in the luggage department.

Wherever he goes, police or security guards accompany him.

His only opportunities for fresh air are walks to a porch area overlooking the runway.

His only contact with the outside world comes when the airport's irregular free wi-fi signal flickers into life. Then he uses Skype.

"I talk to my cousin Yaser, he lives in Norway. I don't have any other close family, my parents died in Iraq when I was 16, and I don't have any brothers or sisters," he says.

It was the desire to make his own family that brought him to Kazakhstan to live with his girlfriend, Olesya Grishenko, now pregnant with their first child.

The Kazakh national met Mohammed on holiday in Dubai when he was working there as an interior designer.

In Kazakhstan, while registering their intention to marry, Mohammed's refugee travel documents went missing, and his Kazakh and UAE visas expired.

He later flew to Turkey in the hope of renewing his Kazakh visa, but was turned back at the border.

"I was deported from Istanbul for lack of a valid visa, and they sent me back to Almaty. But here I also did not have a valid visa so they sent me straight back to Istanbul. Four times I flew back and forth between the two cities," Mohammed says.

Kazakh immigration is keeping Mohammed in the airport's transit area, which legally is not considered Kazakh territory.

Last month, the Kazakh authorities turned down his application for asylum.

Mohammed says he has been preoccupied with a single thought since becoming trapped - how to escape.

"I miss the sunshine, I miss being outside," he says.

"I see all these people leaving the building, and I am just stuck here, I can't go anywhere," he says.

We walk through the sliding door on to the steps where passengers board and disembark from shuttle buses. But Mohammed can go no further.

The sound of plane engines fills the air. Behind Almaty, mountains glisten.

"I get too angry when I come out here," he says. "Because I truly feel that I am in jail."