Male-heavy boards dominate in the start-up mecca of Silicon Valley, which prides itself on progressive thinking and putting talent first. A Reuters survey of the 10 top venture-backed start-ups, as measured by venture funds raised, shows that six do not have any women on the board, including Pinterest. And none has more than one.

Reuters' research relied on publicly available data and discussions with start-up executives and board members.

The gender imbalance has been the norm for years despite some recent signs of change. Google, Facebook and Twitter all went public without a woman on the board. They are more diverse now.

Big, established companies, by contrast, frequently have two or more female directors, based on the 10 largest U.S. tech companies by market value. All of the top 20 have at least one.

The dismal record of start-ups when it comes to gender diversity was highlighted last month when Twitter came under fire for its all-male board on the eve of its public offering. On Thursday, the company announced that it had added former Pearson chief Marjorie Scardino to its board.

Entrepreneurs and executives contacted by Reuters did not question the conclusion that there are few women directors at start-ups, but they frequently described it as unintended, and some such as Pinterest say their executive ranks are more balanced.

Start-ups tend to blame the lack of women on their boards on factors such as their youth, their small boards, their single-minded focus on growth to the exclusion of other priorities, and a scarcity of women steeped in technology. They also blame venture capitalists, who are usually male, usually hold the bulk of board seats - and don't want to see their voting power diluted by adding noninvestor board members.

Critics counter that entrepreneurs who pride themselves on creativity and innovation simply aren't trying hard enough when it comes to gender diversity.

At Pinterest, the focus is on work, said Chief Executive Ben Silbermann, whose board consists of himself and two male venture capitalists. "It's pretty heads down," he said. If the company expands the board and a qualified woman emerges as a candidate, "we'd be open to it," he added.

The outcome of ballots to choose 337 mayors and around 2,500 councilors will be seen as a sign of Maduro's strength, nine months after Chavez died from cancer and he narrowly beat opposition leader Henrique Capriles to win the presidency.

"All patriots must vote so we can give a victory to our commander (Chavez) and guarantee peace and future for the fatherland," Maduro, 51, said on Twitter in exhortation to supporters.

In Caracas shantytowns and elsewhere, pro-Maduro activists woke up supporters before dawn with bugle calls and trumpets in an election mobilization tactic begun under Chavez.

Opponents portray Maduro as a buffoonish autocrat with none of his predecessor's political savvy, and say his continuation of statist economic policies - including a new crackdown on businesses for alleged price-gouging - are disastrous.

"It's important to vote though I don't think it will bring the changes I want," said graphic designer Antonella Gutierrez, 45, on her way to vote at a primary school in a pro-opposition upscale suburb of Caracas nestled under the Avila mountain.

"I want changes from the presidency down. This government is tearing the country into bits, destroying my Venezuela."

Unlike the presidential votes that Maduro won in April and Chavez last year, morning queues appeared thin at poll stations. A healthy turnout of 60 percent or more was forecast however.

Though local issues such as roads, street lights and utility services were bound to affect individual mayoral races, both sides in the polarized OPEC nation also see the overall results as a crucial show of their standing at national level.

The ruling Socialist Party was likely to win a majority of municipalities thanks to its popularity in rural areas, where most of the mayorships are located, while the opposition wants to keep control of big cities such as Caracas and Maracaibo.

Both sides were desperate to win the total popular vote, though most pollsters predict that would again be broadly split down the middle, like the April presidential poll.

Investors are watching the ballot for indications as to whether Maduro will have the strength to push through unpopular economic measures, such as a currency devaluation that would help government finances but also spur inflation.

Protesters have been on the streets of the capital for weeks, clashing with police and vowing to oust Yingluck and eradicate the influence of her self-exiled brother, former Prime Minister Thaksin Shinawatra.

The demonstrations are the latest eruption in nearly a decade of rivalry between forces aligned with the Bangkok-based establishment and those who support Thaksin, a former telecommunications tycoon who won huge support in the countryside with pro-poor policies.

Underscoring the divide, the pro-establishment Democrat Party said all of its members of the House of Representatives would give up their seats because they were unable work with Yingluck's ruling party.

The leader of the protesters, Suthep Thaugsuban, a former Democrat Party deputy prime minister, has called for a final demonstration on Monday to force Yingluck out.

Yingluck said in a televised statement her government was searching for ways to end the conflict.

"We should conduct a referendum so that people can decide what we should do," she said.

Suthep, aware that Yingluck would likely win an election if one were called, has been urging the setting up of a "people's council" of appointed "good people" to replace the government.

Yingluck has dismissed the idea as unconstitutional and undemocratic. She did not spell out the specifics of any referendum but said it was in line with the constitution.

"I'm willing to listen to proposals from the protesters. I'm not addicted to this title," she said. "I'm ready to resign and dissolve parliament if that is what the majority of the Thai people want."

Suthep has told his supporters they had to take back power from what he calls the illegitimate "Thaksin regime", but he told them they could not rely on the army to help.

The army, which ousted Thaksin in 2006, has said it does not want to get involved though it has tried to mediate.

Thaksin fled Thailand in 2008 to avoid a graft conviction but has remained closely involved with his sister's government. The protests were sparked last month by a government bid to introduce an amnesty that would have expunged his conviction.

"VERY BRUTAL"

Critics of the government say it is illegitimate because it is corrupt and buys votes though analysts say it has built real support. Thaksin's critics have also accused him of undermining the monarchy, which he has denied.

Developed by "a loose collective of people who identify as anarchists and work in the tech industry", the Universal Automation plugin, which was added to the Chrome web store in early December, mimics the action of a real-life jobseeker. After the user searches for a job, with one click, the plugin automatically sends a CV to every position advertised on the first page of the results.

"I'm sure you applied for jobs on the internet before and you know it's the most tedious thing to do," said one of the developers, who has asked to remain anonymous. "Most of time you're just sending the CV to as many places as you can and hoping that you'll get a response.

"With Universal Jobmatch it's even worse," the activist told the Guardian. "The majority of postings on the site are spam. If they are not outright attempts at identity theft, a lot of them (and I mean a lot, I would say up to 90% on some queries) are third-party posts which are automatically reposted on the site and link to their websites.

"Now people who use Universal Jobmatch do so because they are forced to do so and they're also forced to apply to jobs posted directly on it, so that they can be monitored by job centres."

More broadly, however, the collective is aiming to highlight the drudgery of work in general.

"We need to look at structural issues, such as role of unemployment in capitalist economy in general and also the particular condition of British economy at the moment. Basically most of work we do is at best socially useless and at worst actively harmful. Constant banging on about strivers, hard-working families, the squeezed middle and so on is only meant to obscure that," said the activist.

"At the same time people who do important work that makes this world a good place to live are a target of constant attacks as shirkers and scroungers and forced into destitution."

When Iain Duncan Smith announced in December 2012 that the Universal Jobmatch website was to be mandatory for all jobseekers, fears were raised that the site would be flooded with bogus jobs.

At the time, Duncan Smith said that only 6,000 jobs had been blocked as inappropriate, and 27 employers removed.

"I don't think we've reached that point where we've said, ‘This is it, take it or leave it,'" Senator Richard Durbin told the ABC program "This Week," when pressed on whether his party would insist on including jobless aid in a final deal.

Durbin, the second-ranking Senate Democrat, said that based on what he has heard from Senator Patty Murray, the lead Democratic negotiator on the budget, the fiscal talks are making progress and moving in the right direction.

The House of Representatives and Senate budget panel, created after the government shutdown in October, is discussing a two-year accord that would ease the impact of across-the-board spending cuts known as the "sequester" and lower the near-term risk of another damaging fiscal showdown.

Durbin's comments signaled some flexibility on the issue of jobless aid. House of Representatives Democratic leader Nancy Pelosi said last week that Democrats "cannot support" a budget deal without an extension of unemployment insurance. Pelosi later clarified that she would like to see jobless benefits included in the budget deal but that she would be open to the idea of passing it under separate legislation.

Speaking on ABC on Sunday, Republican Senator Rob Portman, who is a member of the negotiating committee, expressed optimism about a fiscal deal, saying he hoped it could come together by the end of the week.

An extension of emergency unemployment benefits is a priority for President Barack Obama and his Democratic allies in Congress. Democrats have warned that without an extension, federal benefits will expire for some 1.3 million Americans in the week of December 28.

Democrats see a budget deal as one of the best legislative vehicles for passing an extension of the jobless aid, though they have said there are other options they could consider.

Federal unemployment benefits kick in for out-of-work Americans who have exhausted their state unemployment aid, which in many states runs out after 26 weeks.

The emergency federal aid began during the Great Recession in 2008 and has been renewed every year since.

Though government figures on Friday showed the U.S. unemployment rate fell to a five-year low of 7 percent in November, many Democrats say the U.S. job market is still far from robust and long-term unemployment remains a problem for many Americans.

The gesture rejecting Moscow's historic influence over Ukraine came after opposition leaders told hundreds of thousands of demonstrators on Kiev's Independence Square to keep up pressure on Yanukovich to sack his government.

The protesters are furious that the government decided last month to ditch a landmark pact with the European Union in favour of closer economic cooperation with Moscow, Ukraine's Soviet-era overlord.

Yanukovich's sudden tack towards Russia has provoked the biggest street protests since the 2004-5 Orange Revolution, when people power forced a re-run of a fraud-tainted election and thwarted his first run for the presidency.

"Yanukovich, you are next!" chanted protesters as they took turns to hack at the prostrate - and now headless - red granite statue of Lenin, leader of the 1917 Bolshevik revolution.

Cheered by the crowd, a young woman planted an EU flag on the pedestal where the 3-1/2 metre high statue had stood since 1946. Opposition leaders denied any link to its removal.

The authorities and protesters have confronted each other for weeks, raising fears for political and economic stability in the former Soviet republic of 46 million people.

"This is a decisive moment when all Ukrainians have gathered here because they do not want to live in a country where corruption rules and where there is no justice," said Vitaly Klitschko, a world heavyweight boxing champion-turned-politician.

Ukraine's opposition accuses Yanukovich, who met Russian President Vladimir Putin on Friday, of preparing to take the country into a Moscow-led customs union, which they see as an attempt to recreate the Soviet Union.

"RAZOR'S EDGE"

Yanukovich has said he decided to shelve the EU trade deal because it would have been too costly for Ukraine's struggling economy and the country needs more time to prepare. He says he is preparing a "strategic partnership" with Russia, but has not committed to joining the customs union.

"We are on a razor's edge between a final plunge into cruel dictatorship and a return home to the European community," jailed opposition leader Yulia Tymoshenko said in a message to Sunday's rally, read out by her daughter Yevgenia.

Last weekend, riot police beat protesters and journalists, drawing EU condemnation and swelling the protesters' ranks.

At churches, mosques, synagogues and community halls from the Limpopo River to the Cape, millions offered praise and reflected on a man celebrated as "Father of the Nation" and as a global beacon of integrity, rectitude and reconciliation.

Mandela, South Africa's first black president who steered his nation out of apartheid and into multi-racial democracy, died on Thursday at the age of 95 after months of illness.

Since then, the country has been gripped by an outpouring of emotion unrivalled since Mandela's release from 27 years of prison in 1990 and his subsequent election victory. Crowds have piled flowers, candles, balloons and messages outside his Johannesburg home.

At the cavernous Regina Mundi church in Soweto, South Africa's largest Catholic Church, hundreds of mourners, young and old, gathered to pray for Mandela and the nation's future.

"People are praying that there will be change, that we will come together," said Gladys Simelane, an office manager.

Mandela's former wife Winnie Madikizela-Mandela, dressed in black, attended a Methodist service in the northern Johannesburg suburb of Bryanston, where President Jacob Zuma hailed the values of the country's most beloved statesman.

"He believed in forgiveness and he forgave even those who kept him in jail for 27 years," Zuma said in a eulogy.

"He stood for freedom. He fought against those who oppressed others. He wanted everyone to be free."

The day of prayers opens an official program of mourning that includes a memorial service in a Johannesburg stadium on Tuesday and a state funeral next Sunday at Mandela's Eastern Cape ancestral home of Qunu - expected to be one of the biggest gatherings of world leaders in recent history.

Fifty-nine foreign heads of state or government have so far said they will attend the memorial or the funeral, a foreign ministry spokesman said. Large contingents of royalty and celebrities are also expected.

U.S. President Barack Obama, U.N. Secretary-General Ban Ki-moon and British Prime Minister David Cameron will be among those at Tuesday's memorial.

"So watch where you step," physicist Joe Incandela said as we descended in an elevator 27 stories below the surface of the Earth.

In the event of a fire, take the elevator back up, he said -- a rule opposite from anywhere else. We also wore orange hard hats for the subterranean journey. You know, just in case.

From the cornfield beside the CMS buildings, against an idyllic mountain backdrop, you might not guess this is an entry point into the collider, the world's largest science experiment. The quiet winding roads through the French village of Cessy contrast with the subatomic violence of the particle accelerator below, which sends millions of protons smashing against each other every second.

We were able to go underground here thanks to a seven-year excavation of almost 250,000 cubic meters of soil and rock, a process that also uncovered a Roman villa nearby. That all led to the construction of a modern beige office complex on the surface, above the complicated particle detector that's waiting for us below.

CMS -- which stands for Compact Muon Solenoid -- sits along a 17-mile circular tunnel straddling the French-Swiss border. On the opposite side of the ring, in Switzerland, is ATLAS, another important experiment. Both projects are operated by the European Organization for Nuclear Research (CERN), the physics laboratory that hosts the collider.

CMS and ATLAS share the same scientific goals -- finding new particles and properties of the universe -- but their architecture and technical systems are different. Fabiola Gianotti, former spokeswoman for ATLAS, said there's a healthy competition between the groups that pushes both to do their best.

"I think we would not have produced so many beautiful results so quickly if this 'friendly competition' was not there," she said. What is the Higgs boson and why is it important?

A $10 billion search for answers

The Higgs boson is a particle whose existence was confirmed at the Large Hadron Collider by both ATLAS and CMS in 2012. This year's Nobel Prize in Physics will be awarded to Francois Englert and Peter Higgs on Tuesday for their theories about this particle.

A simplified refresher on the idea: Throughout empty space is a phenomenon called the Higgs field, which is all around us. If this field gets excited, a tiny component will break off -- and that is the Higgs boson. This concept helps solve a fundamental question about the universe: Why does matter have mass?

Apple and Samsung are engaged in global litigation over each other's intellectual property. The two mobile technology rivals have gone to trial twice in the last two years in a San Jose, California federal court, and juries have awarded Apple a total of roughly $930 million.

In court filings, Apple asked U.S. District Judge Lucy Koh to order Samsung to pay $15.7 million of the total amount Apple has spent in legal fees.

"Awarding fees to Apple 'flows quite naturally' from the jury's willfulness verdict as well as Samsung's extensive record of willful, deliberate, and calculated decisions to copy the iPhone, in blatant disregard for Apple's IP," Apple's attorneys said in its filing.

Apple could not immediately be reached for comment, and Samsung declined to comment.

In its fee motion, Apple said it has paid the Morrison & Foerster law firm approximately $60 million through last month, not counting lawyers who had billed less than $100,000 on the case.

Apple received "a significant discount" on Morrison & Foerster's standard rates, it said, because of its longtime client relationship with the firm. In addition, Apple expected to pay its other main outside firm, WilmerHale, approximately $2 million in fees for a week-long damages retrial that took place last month.

President Jacob Zuma said Mandela would be buried on December 15 at his ancestral home in the Eastern Cape.

South Africans heard from Zuma late on Thursday that their first black president, a Nobel Peace Prize laureate, had died peacefully at his Johannesburg home in the company of his family after a long illness.

On Friday, the country's 52 million people absorbed the news that the statesman, a global symbol of reconciliation and peaceful co-existence, had departed forever.

Zuma also announced Mandela would be honored at a December 10 memorial service at Johannesburg's Soccer City stadium, the site of the 2010 World Cup final.

"We will spend the week mourning his passing. We will also spend it celebrating a life well lived," Zuma said.

He added that Mandela would be laid to rest at his ancestral village of Qunu, 700 km (450 miles) south of Johannesburg, in a plot where three of his children and other close family members are buried.

Despite reassurances from public figures that Mandela's death at 95, while sorrowful, would not halt South Africa's advance from its apartheid past, there were those who expressed unease about the absence of a man famed as a peacemaker.

"It's not going to be good, hey! I think it's going to become a more racist country. People will turn on each other and chase foreigners away," said Sharon Qubeka, 28, a secretary from Tembisa township. "Mandela was the only one who kept things together."

Flags flew at half mast across the country, and trade was halted for five minutes on the Johannesburg stock exchange.

But the mood was not all somber. Hundreds filled the streets around Mandela's home in the upmarket Johannesburg suburb of Houghton, many singing songs of tribute and dancing.

The crowd included toddlers carrying flowers, domestic workers still in uniform and businessmen in suits.

Another veteran anti-apartheid campaigner, former Anglican Archbishop of Cape Town Desmond Tutu, said that like all South Africans he was "devastated" by Mandela's death.

"Let us give him the gift of a South Africa united, one," Tutu said, holding a mass in Cape Town's St George's Cathedral.

Tributes continued to pour in for Mandela, who had been suffering for nearly a year from a recurring lung illness dating back to the 27 years he spent in apartheid jails, including the Robben Island penal colony.

Group A: Brazil, Croatia, Mexico, Cameroon.

Group B: Spain, Netherlands,Chile, Australia.

Group C: Colombia, Greece, Ivory Coast, Japan.

Group Uruguay, Costa Rica, England, Italy.

Group E: Switzerland, Ecuador, France,Honduras.

Group F: Argentina, Bosnia, Iran, Nigeria.

Group G: Germany, Portugal,Ghana, USA.

Group H: Belgium, Algeria, Russia, Korea.

It suggested that as more and more devices are manufactured, supplies of key elements, particularly metals, will be strained.

Potential substitute materials are either inadequate or non-existent, researchers said.

One scientist called the findings "an important wake-up call".

Andrea Sella, of University College London - who was unconnected to the study - told website The Conversation that it was the first time the issue had been explored in such detail.

Researchers at Yale University, led by Prof Thomas Graedel, analysed the use of 62 metals or metalloids commonly found in popular technology, such as smartphones.

Troubling It found that none of the 62 had alternatives that performed equally well. Twelve had no alternative, Prof Graedal found.

The scope for serious disruption because of material shortages is increasingly troubling technology companies.

Rare materials are expensive to extract, and their processing comes with considerable environmental concerns. Political factors also play a part: in 2010, China restricted the export of some materials, known as rare earth elements.

It said this was because of environmental issues, but some observers noted that the restrictions had two distinct effects - the price of the elements increased fivefold, and Chinese companies were simultaneously given the upper hand in using the precious materials at lower cost.

Disrupted Natural disasters bring another unpredictable risk.

In 2011, serious flooding in Thailand disrupted global supply chains as the country is a hub for hardware manufacture.

Shortages of storage devices extended well into 2012, according to research company IHS iSuppli, with hard-drive supplies the hardest hit.