Rusty rocks reveal ancient origin of photosynthesis

SUN-WORSHIP began even earlier than we thought. The world's oldest sedimentary rocks suggest an early form of photosynthesis may have evolved almost 3.8 billion years ago, not long after life appeared on Earth.

A hallmark of photosynthesis in plants is that the process splits water and produces oxygen gas. But some groups of bacteria oxidise substances like iron instead – a form of photosynthesis that doesn't generate oxygen. Evolutionary biologists think these non-oxygen-generating forms of photosynthesis evolved first, giving rise to oxygen-generating photosynthesis sometime before the Earth's atmosphere gained oxygen 2.4 billion years ago (New Scientist, 8 December 2012, p 12).

But when did non-oxygen-generating photosynthesis evolve? Fossilised microbial mats that formed in shallow water 3.4 billion years ago in what is now South Africa show the chemical fingerprints of the process. However, geologists have long wondered whether even earlier evidence exists.

The world's oldest sedimentary rocks – a class of rock that can preserve evidence of life – are a logical place to look, says Andrew Czaja of the University of Cincinnati in Ohio. These rocks, which are found in Greenland and date back almost 3.8 billion years, contain vast deposits of iron oxide that are a puzzle. "What could have formed these giant masses of oxidised iron?" asks Czaja.

To investigate, he analysed the isotopic composition of samples taken from the oxidised iron. He found that some isotopes of iron were more common than they would be if oxygen gas was indiscriminately oxidising the metal. Moreover, the exact isotopic balance varied subtly from point to point in the rock.

Both findings make sense if photosynthetic bacteria were responsible for the iron oxide, says Czaja. That's because these microbes preferentially oxidise only a small fraction of the dissolved iron, and the iron isotopes they prefer vary slightly as environmental conditions change (Earth and Planetary Science Letters, doi.org/kh5). His findings suggest that this form of photosynthesis appeared about 370 million years earlier than we thought.

It is "the best current working hypothesis for the origin of these deposits", says Mike Tice of Texas A&M University in College Station – one of the team who analysed the 3.4-billion-year-old microbial mats from South Africa.

William Martin at the University of Düsseldorf, Germany, agrees. "Anoxygenic photosynthesis is a good candidate for the isotope evidence they see," he says. "Had these fascinating results been collected on Mars, the verdict of the jury would surely remain open," says Martin Brasier at the University of Oxford. "But [on Earth] opinion seems to be swinging in the direction of non-oxygen-generating photosynthesis during the interval from 3.8 to 2.9 billion years ago."

This article appeared in print under the headline "Photosynthesis has truly ancient origins"

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China reports second fatal case of bird flu this year

BEIJING: A man in southwestern China has died of bird flu, health authorities said Saturday, becoming the second fatality from the H5N1 virus this year.

The 31-year-old died in hospital in the city of Guiyang on Friday, the Guizhou province health department said in a statement, adding that no other human cases of avian flu had been reported in the province.

Another city resident, a 21-year-old woman, died from the virus earlier this month.

The Xinhua news agency said both of them had come into close contact with birds but it was not known if the cases were related.

The H5N1 virus typically spreads from birds to humans through direct contact, but experts fear it could mutate into a form transmissible between humans with the potential to trigger a pandemic.

More than 365 people have died of bird flu globally since the virus re-emerged in 2003, according to the World Health Organization.

Its figures show that China saw 25 deadly cases of the virus between 2003 and 2009 before numbers tailed off to one fatality in each of the three following years. The deadliest year of the past decade in China saw eight deaths in 2006.

China is considered one of the nations most at risk from bird flu epidemics because it has the world's biggest poultry population and many chickens in rural areas are kept close to humans.

China has in the past been accused of covering up the extent of bird flu outbreaks, exacerbating fears when new cases are reported.

Separate outbreaks among birds were reported last year in the northern region of Ningxia and the remote northwestern region of Xinjiang, prompting massive culls of chickens.

- AFP/ir

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Crave Ep. 110: Prevent a hangover with the worlds first 'sober pill'?

Prevent a hangover with the worlds first 'sober pill'? Ep 110

Subscribe to Crave:

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Cheers! Scientists have created what may be the world's first pill that can make you sober if you've gone a little too far with the booze. Russian meteorite fragments go up for sale on online, as do Milla Jovovich's shorts. And later this year a man will have surgery to attach a bionic hand that can feel touch sensations.

Crave stories:

- Russian meteorite fragments pop up for sale online

- Amazon opens celebrity memorabilia store

- Nanotech 'sober pill' could one day de-drunk you

- This sheet turns your windows into mirrors

- Man to get first bionic hand that can 'feel'

- Sony PS4 event skewered in animated parody

- Crave giveaway! Kanex Sydnee four-port recharging station

Social networking:

- Stephen on Twitter

- Stephen on Google+

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Space Pictures This Week: Space Rose, Ghostly Horses

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  Space Rose

  Image courtesy T.A. Rector and H. Schweiker, UAA/WIYN/NOAO/NSF

  Planetary nebula Sh2-174 "blooms" like a rose in a picture released this week by the National Optical Astronomy Observatory (NOAO).

  Nebulae are created when low-mass stars shed their outer layers at the end of their lives. The core of the dying star, called a white dwarf, usually remains at the center of the nebula.

  But not so for the oddly positioned Sh2-174: Its white dwarf is located in the right part of the nebula, in the blue gas pictured above. (See more nebula pictures.)

  Published February 22, 2013

  
  











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  Universal Delivery

  Photograph courtesy NASA

  An unpiloted resupply vehicle snapped this picture as it approached the International Space Station this week.

  The vehicle provided the 34 crew members on board with essential supplies, including oxygen, water, spare parts, even logistics equipment—2.9 tons of supplies in all. (See pictures of early U.S. spaceflight.)

  Published February 22, 2013

  
  











• 
  
  
  
  
  
  
  

  Everglades of Europe

  Image courtesy Jesse Allen and Robert Simmon, EO-1/NASA/USGS

  The Danube cuts a jade path across part of the Danube Biosphere Reserve in the Ukraine on its way to the Black Sea in an image captured February 5 by NASA's Earth Observing-1 satellite.

  Europe's largest river, the Danube spans 309,447 square miles (801,463 square kilometers) and winds its way through 19 countries.

  Called the "Everglades of Europe," the Danube delta is home to more than 300 species of birds and 45 species of fish, according to NASA's Earth Observatory. (See more river pictures.)

  Published February 22, 2013

  
  











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  Bird's-Eye View

  Image by Maurizio Cabibbo, My Shot

  Photographer Maurizio Cabibbo submitted this picture of the chaotic center of the Cygnus, or Swan, constellation on February 11 to the National Geographic photo community My Shot.

  Resembling a swan flying across the night sky, Cygnus is easily seen in the summer in the Northern Hemisphere, according to NASA.

  Published February 22, 2013

  
  











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  Spirit Horses

  Photograph by Andre Erlich, Your Shot

  An aurora casts a ghostly glow over horses in northern Iceland in a picture submitted to National Geographic's My Shot photography community on February 18.

  Named after Aurora, the Roman goddess of dawn, the vivid beams of light from aurora borealis result from collisions between charged particles released from the sun's atmosphere and gaseous particles in Earth's atmosphere. (See more aurora pictures: "Solar Flare Sparks 'Snakes,' 'Spears.'")

  Published February 22, 2013

  
  











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  Image courtesy SDO/NASA

  Published February 22, 2013

  
  

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Great Energy Challenge Blog

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Cyberattacks Bring Attention to Security Reform

Recent accusations of a large-scale cyber crime effort by the Chinese government left many wondering what immediate steps the president and Congress are taking to prevent these attacks from happening again.

On Wednesday, the White House released the administration's Strategy on Mitigating the Theft of U.S. Trade Secrets as a follow-up to the president's executive order. The strategy did not outwardly mention China, but it implied U.S. government awareness of the problem.

"We are taking a whole of government approach to stop the theft of trade secrets by foreign competitors or foreign governments by any means -- cyber or otherwise," U.S. Intellectual Property Enforcement Coordinator Victoria Espinel said in a White House statement.

As of now, the administration's strategy is the first direct step in addressing cybersecurity, but in order for change to happen Congress needs to be involved. So far, the Cyber Intelligence Sharing and Protection Act (CISPA) is the most notable Congressional legislation addressing the problem, despite its past controversy.

Last April, CISPA was introduced by House Intelligence Committee Chairman Mike Rogers, R-Mich., and Rep. Dutch Ruppersberger, D-Md. The act would allow private companies with consumer information to voluntarily share those details with the NSA and the DOD in order to combat cyber attacks.

Peter Parks/AFP/Getty Images

The companies would be protected from any liabilities if the information was somehow mishandled. This portion of the act sounded alarm bells for CISPA's opponents, like the ACLU, which worried that this provision would incentivize companies to share individuals' information with disregard.

CISPA passed in the House of Representatives, despite a veto threat from the White House stemming from similar privacy concerns. The bill then died in the Senate.

This year, CISPA was reintroduced the day after the State of the Union address during which the president declared an executive order targeting similar security concerns from a government standpoint.

In contrast to CISPA, the executive order would be initiated on the end of the government, and federal agencies would share relevant information regarding threats with private industries, rather than asking businesses to supply data details. All information shared by the government would be unclassified.

At the core of both the executive order and CISPA, U.S. businesses and the government would be encouraged to work together to combat cyber threats. However, each option would clearly take a different route to collaboration. The difference seems minimal, but has been the subject of legislative debates between the president and Congress for almost a year, until now.

"My response to the president's executive order is very positive," Ruppersberger told ABC News. "[The president] brought up how important information sharing is [and] by addressing critical infrastructure, he took care of another hurdle that we do not have to deal with."

Addressing privacy roadblocks, CISPA backers said the sharing of private customer information with the government, as long as personal details are stripped, is not unprecedented.

"Think of what we do with HIPAA in the medical professions; [doctors do not need to know] the individual person, just the symptoms to diagnose a disease," Michigan Gov. John Engler testified at a House Intelligence Committee hearing in an attempt to put the problem into context.

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Mood-sensing smartphone tells your shrink how you feel

PEOPLE with anxiety, depression or stress are often asked to record their mood changes throughout the day, helping psychologists fine-tune their treatment. But they often forget, recording only sparse information at best. Now an emotion-sensing smartphone app that automatically generates someone's "mood diary" could give psychologists all the data they need.

It's the brainchild of Matt Dobson and Duncan Barclay, founders of speech recognition firm EI Technologies, based in Saffron Walden, UK. Instead of relying on people writing diaries, the app, called Xpression, listens for telltale changes in a person's voice that indicate whether they are in one of five emotional states: calm, happy, sad, angry or anxious/frightened. It then lists a person's moods against the times they change, and automatically emails the list to their psychologist at the end of the day.

To work, the app has to be always on, listening out for the user's voice once every second, whether they are talking to family, friends, colleagues or even pets. It also listens in on phone calls. If the user is silent, the app does nothing. Crucially for the users' privacy, it doesn't record their words, instead seeking out telltale acoustic features – like pitch – that are indicative of emotional state.

This kind of emotion recognition via voice pattern already works well and is a "hot area" of research, says Stephen Cox, head of the speech processing lab at the University of East Anglia in Norwich, UK, who is scientific adviser for the firm.

Initially, Xpression will send 200-millisecond-long acoustic snapshots to a remote server where a machine-learning system will work out a person's emotional state before sending it back to the app for storage. Factors like voice loudness, intensity, changes in pitch and speaking pace allow the system to accurately estimate somebody's emotional state. "We extract acoustic features and let the machine-learning system work it out," says Cox. This ability will be built into the app itself eventually, says Dobson.

There's a strong need for this kind of technology, says Adrian Skinner, a clinical psychologist with the UK's National Health Service in Harrogate, North Yorkshire. "With conditions like depression, people tend to stop doing things like filling in mood diaries. If this app gives us more complete diaries it could help us better find the day-to-day triggers that raise or lower a patient's mood," he says.

The firm is a finalist in a UK government competition to identify the nation's top mobile tech company, to be judged on 26 February. An insurance company has already expressed an interest in using the app to ensure the workplace stress therapy it pays for is effective. Clinical trials are due to take place later this year.

This article appeared in print under the headline "We know how you really feel"

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

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Cricket: Hyderabad Test still on, says Australia chief

SYDNEY: Australia plan to play the second Test against India in Hyderabad as scheduled next week despite deadly bomb attacks in the city on the eve of the Test series opener, reports said on Friday.

The twin blasts on Thursday killed 14 people and wounded dozens more in a busy neighbourhood in the southern Indian city, raising questions over whether Australia would play the second Test starting on March 2.

But Cricket Australia chief executive James Sutherland told Fairfax newspapers the match was still on as planned as Australia prepared for the opening match in the four-Test series in Chennai starting later Friday.

"As far as I'm concerned we are playing the second Test in Hyderabad next week. That's where we are at," said Sutherland, who is with the team in Chennai.

Sutherland told Fairfax he was happy to continue to Hyderabad where the team is scheduled to arrive on Wednesday.

"We've got great confidence in the BCCI (Board of Control for Cricket in India) and the relevant authorities here to be able to prepare as best as possible for whatever issues may change from day to day," he said.

"We're very comfortable with everything that has been done so far on this tour."

"We'll obviously take advice from relevant authorities and work with the BCCI and others here to make assessments around Hyderabad but at the same time plans have been in place for a long time," Sutherland said.

"At this stage I wouldn't be calling into question things going ahead in Hyderabad."

He added that team manager Gavin Dovey had sent players text messages overnight updating them on the blasts and that security had been stepped up.

Dozens of extra police reportedly surrounded the Chennai hotel where the Australian and Indian teams are staying.

Captain Michael Clarke said his players were focused on the Chennai game.

"From the team's point of view, our focus is wholly and solely on the field because we've got people off the field who are experts in what is going on. We'll be advised by them," he said.

"Our thoughts and prayers are with all the people of Hyderabad who have been affected."

Earlier, media reports raised doubts over the tour.

"Australia's cricket tour of India has been plunged into uncertainty," said the Herald-Sun newspaper, while the Sydney Morning Herald carried a headline "Hyderabad Test in doubt as bombings rock city".

Australia pulled out of a tour to Pakistan in 2008 over security concerns after a series of bombings in the troubled country. They also refused to play any matches in the 1996 World Cup in Sri Lanka after bombings there.

Cricket Australia, which said the safety of players was paramount, earlier said the tourists had received "no information to suggest there is any threat to the team" but that talks were ongoing.

The attacks targeted a Hindu district in the city, a hub of India's computing industry in the southern state of Andhra Pradesh, home to local offices of Google and Microsoft among other Western IT companies.

After the blasts, the Foreign Affairs Department in Canberra warned Australians following the tour in India that terror attacks could happen anywhere.

"We advise you to exercise a high degree of caution in India at this time because of the risk of terrorism, civil unrest, crime and vehicle accidents," the department said.

"Terrorist attacks could occur anywhere at any time in India with little or no warning," it said.

"Possible targets include public places in New Delhi, Mumbai and other major cities, and Indian security and political interests."

However, the overall level of advice for Australians in India has not changed, with the department recommending people exercise a high degree of caution.

No major international cricket has been played in Pakistan since a deadly attack on the Sri Lankan team bus by armed militants in Lahore in 2009.

- AFP/ck

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Zendesk hack snares user data from Twitter, Tumblr, Pinterest

At a time when it seems no company is immune from hackers, user information from three high-profile social-networking sites has been compromised due to a hack at another company.

Customer support service Zendesk revealed today that it had been the victim of a security breach and that information from three of its clients had been downloaded. As first reported by Wired, those three clients are Twitter, Pinterest, and Tumblr.

Zendesk revealed the hack in a company blog post today that said the vulnerability was immediately identified and patched.

Our ongoing investigation indicates that the hacker had access to the support information that three of our customers store on our system. We believe that the hacker downloaded email addresses of users who contacted those three customers for support, as well as support email subject lines. We notified our affected customers immediately and are working with them to assist in their response.

Although Zendesk did not identity the clients by name, some users of the social-networking services began receiving warnings that they may have been affected by the breach. Wired published warnings sent by each company that identified Zendesk as the point of the leak.

One e-mail sent by Tumblr to a CNET associate said hackers may have had access to the subject lines and e-mail addresses of messages sent to Tumblr support.

The subject lines of your emails to Tumblr Support may have included the address of your blog which could potentially allow your blog to be unwillingly associated with your email address.

Any other information included in the subject lines of emails you've sent to Tumblr Support may be exposed. We recommend you review any correspondence you've addressed to support@tumblr.com, abuse@tumblr.com, dmca@tumblr.com, legal@tumblr.com, enquiries@tumblr.com, or lawenforcement@tumblr.com.

Founded in 2007, the cloud-based customer service solution provider announced last month that it had signed up its 25,000th customer.

The hacks come just days after Apple and Facebook revealed that their respective employees' computers fell victim to unauthorized access.

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Oldest Known Wild Bird Hatches Chick at 62

Wisdom, the oldest known wild bird, has yet another feather in her cap—a new chick.

The Laysan albatross (Phoebastria immutabilis)—62 years old at least—recently hatched a healthy baby in the U.S. Midway Atoll National Wildlife Refuge, her sixth in a row and possibly the 35th of her lifetime, according to the U.S. Geological Survey's (USGS) North American Bird Banding Program. (Related: "51-Year-Old Albatross Breaks N. American Age Record [2003].")

But Wisdom's longevity would be unknown if it weren't for a longtime bird-banding project founded by USGS research wildlife biologist Chandler Robbins.

Now 94, Robbins was the first scientist to band Wisdom in 1956, who at the time was "just another nesting bird," he said. Over the next ten years, Robbins banded tens of thousands of black-footed albatrosses (Phoebastria nigripes) and Laysan albatrosses as part of a project to study the behavior of the large seabirds, which at the time were colliding with U.S. Navy aircraft.

Robbins didn't return to the tiny Pacific island—now part of the U.S. Papahānaumokuākea Marine National Monument—until 2002, when he "recaptured as many birds as I could in hopes that some of them would be the old-timers."

Indeed, Robbins did recapture Wisdom—but he didn't know it until he got back to his office at the Patuxent Wildlife Research Center in Laurel, Maryland, and checked her band number in the database.

"That was real exciting, because we didn't think the chances of finding one that old would be that good," Robbins said Wednesday in an interview from his office at the Patuxent center, where he still works.

Chandler Robbins counts birds in Maryland's Patuxent Research Refuge.

Photograph by David H. Wells, Corbis

Albatrosses No Bird Brains

Bigger birds such as the albatross generally live longer than smaller ones: The oldest bird in the Guinness Book of Animal Records, a Siberian white crane (Leucogeranus leucogeranus), lived an unconfirmed 82 years. Captive parrots are known to live into their 80s. (See National Geographic's bird pictures.)

The Laysan albatross spends most of the year at sea, nesting on the Midway Atoll (map) in the colder months. Birds start nesting around five years of age, which is how scientists knew that Wisdom was at least five years old in 1956.

Because albatrosses defend their nests, banding them doesn't require a net or a trap as in the case of other bird species, Robbins said—but they're far from tame.

"They've got a long, sharp bill and long, sharp claws—they could do a job on you if you're not careful how to handle them," said Robbins, who estimates he's banded a hundred thousand birds.

For instance, "when you're not looking, the black-footed albatross will sneak up from behind and bite you in the seat of the pants."

But Robbins has a fondness for albatrosses, and Wisdom in particular, especially considering the new dangers that these birds face.

Navy planes are no longer a problem—albatross nesting dunes were moved farther from the runway—but the birds can ingest floating bits of plastic that now inundate parts of the Pacific, get hooked in longlines meant for fish, and be poisoned by lead paint that's still on some of Midway Atoll's buildings. (Also see "Birds in 'Big Trouble' Due to Drugs, Fishing, More.")

That Wisdom survived so many years avoiding all those hazards and is still raising young is quite extraordinary, Robbins said.

"Those birds have a tremendous amount of knowledge in their little skulls."

"Simply Incredible"

Wisdom's accomplishments have caught the attention of other scientists, in particular Sylvia Earle, an oceanographer and National Geographic Explorer in Residence, who said by email that Wisdom is a "symbol of hope for the ocean." (National Geographic News is part of the National Geographic Society.)

Earle visited Wisdom at her nest in January 2012, where she "appeared serenely indifferent to our presence," Earle wrote in the fall 2012 issue of the Virginia Quarterly Review.

"I marveled at the perils she had survived during six decades, including the first ten or so years before she found a lifetime mate. She learned to fly and navigate over thousands of miles to secure enough small fish and squid to sustain herself, and every other year or so, find her way back to the tiny island and small patch of grass where a voraciously hungry chick waited for special delivery meals."

Indeed, Wisdom has logged an estimated two to three million miles since 1956—or four to six trips from Earth to the moon and back, according to the USGS. (Related: "Albatross's Effortless Flight Decoded—May Influence Future Planes.")

Bruce Peterjohn, chief of the North American Bird Banding Program, called Wisdom's story "simply incredible."

"If she were human, she would be eligible for Medicare in a couple years—yet she is still regularly raising young and annually circumnavigating the Pacific Ocean," he said in a statement.

Bird's-Eye View

As for Robbins, he said he'd "love to get out to Midway again." But in the meantime, he's busy going through thousands of bird records in an effort to trace their life histories.

There's much more to learn: For instance, no one has ever succeeded in putting a radio transmitter on an albatross to follow it throughout its entire life-span, Robbins noted.

"It would be [an] exciting project for someone to undertake, but I'm 94 years old," he said, chuckling. "It wouldn't do much for me to start a project at my age."

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Arias Challenged On Pedophilia Claim

Accused murderer Jodi Arias was challenged today by phone records, text message records, and her own diary entries that appeared to contradict her claim that she caught her ex-boyfriend, Travis Alexander, looking at pictures of naked boys.

Arias had said during her testimony that one afternoon in January 2008, she walked in on Alexander masturbating to pictures of naked boys. She said she fled from the home, threw up, drove around aimlessly, and ignored numerous phone calls from Alexander because she was so upset at what she had seen.

The claim was central to the defense's accusation that Alexander was a "sexual deviant" who grew angry and abusive toward Arias in the months after the incident, culminating in a violent confrontation in June that left Alexander dead.

Arias claimed she killed him in self-defense. She could face the death penalty if convicted of murder.

Catching Up on the Trial? Check Out ABC News' Jodi Arias Trial Coverage

Today, prosecutor Juan Martinez, who has been aggressive in questioning witnesses throughout the trial, volleyed questions at her about the claim of pedophilia, asking her to explain why her and Alexander's cell phone records showed five calls back and forth between the pair throughout the day she allegedly fled in horror. Some of the calls were often initiated Arias, according to phone records.

Jodi Arias Doesn't Remember Stabbing Ex-Boyfriend Watch Video

Jodi Arias Murder Trial: Testimony About Ex's Death Watch Video

Arias on Ex-Boyfriend's Death: 'I Don't Remember' Watch Video

She and Alexander also exchanged text messages throughout the afternoon and evening at a time when Arias claims the pedophilia incident occurred. In those messages they discuss logistics of exchanging one another's cars that night. Alexander sends her text messages about the car from a church social event he attended that night that she never mentioned during her testimony.

Arias stuck by her claim that she saw Alexander masturbating to the pictures, and her voice remained steady under increasingly-loud questioning by Martinez.

But Martinez also sparred with Arias on the stand over minor issues, such as when he asked Arias detailed questions about the timing and order of events from that day and Arias said she could not remember them.

"It seems you have problems with your memory. Is this a longstanding thing? Since you started testifying?" Martinez asked.

"No it goes back farther than that. I don't know even know if I'd call it a problem," Arias said.

"How far back does it go? You don't want to call them problems, are they issues? Can we call them issues? When did you start having them?" he asked in rapid succession. "You say you have memory problems, that it depends on the circumstance. Give me the factors that influence that."

"Usually when men like you or Travis are screaming at me," Arias shot back from the stand. "It affects my brain, it makes my brain scramble."

"You're saying it's Mr. Martinez's fault?" Martinez asked, referring to himself in the third person.

"Objection your honor," Arias' attorney finally shouted. "This is a stunt!"

Timeline of the Jodi Arias Trial

Martinez dwelled at one point about a journal entry where Arias wrote that she missed the Mormon baptism of her friend Lonnie because she was having kinky sex with Alexander. He drew attention to prior testimony that she and Alexander used Tootsie Pops and Pop Rocks candy as sexual props.

"You're trying to get across (in the diary entry) that this involved a sexual liaison with Mr. Alexander right?" he asked. "And you're talking about Tootsie Pops and Pop Rocks?"

"That happened also that night," Arias said.

"You were there, enjoying it, the Tootsie Pops and Pop Rocks?" he asked again, prompting a smirk from Arias.

"I enjoyed his attention," Arias said.

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