Mystery ring of radiation briefly encircled Earth

What were you doing last September? The charged particles that dance around Earth were busy. Unbeknown to most earthlings, a previously unseen ring of radiation encircled our planet for nearly the whole month – before being destroyed by a powerful interplanetary shock wave.

We already knew that two, persistent belts of charged particles, called the Van Allen radiation belts, encircle Earth. The discovery of a third, middle ring by NASA's twin Van Allen probes, launched in August 2012, suggests that these belts, which have puzzled scientists for over 50 years, are even stranger than we thought. Working out what caused the third ring to develop could help protect spacecraft from damaging doses of radiation.

Charged particles get trapped by Earth's magnetic field into two distinct regions, forming the belts. The inner belt, which extends from an altitude of 1600 to 12,900 kilometres, is fairly stable. But the outer belt, spanning altitudes ranging from 19,000 to 40,000 kilometres, can vary wildly. Over the course of minutes or hours, its electrons can be accelerated to close to the speed of light, and it can grow to 100 times its usual size.

Mystery acceleration

No one is sure what causes these "acceleration events", although it seems to have something to do with solar activity interacting with the Earths' magnetic field.

"That's one of the key things the probes are in place to understand," says Dan Baker of the University of Colorado, Boulder. "How does this cosmic accelerator, operating just a few thousand miles above our head, accelerate electrons to such extraordinarily high energies?"

When the Van Allen probes started taking data on 1 September 2012, one of these mysterious events was already under way. "We came in the middle of the movie there," Baker says. But otherwise, he says, "What we expected was what we saw when we first turned on: two distinct belts, separated."

That changed a day later when, to the team's surprise, an extra ring developed between the inner and outer ones. "We watched it develop right before our eyes," Baker says. The new, middle ring was relatively narrow, and its electrons had energies between 4 and 7.5 megaelectronvolts - about the same as in the outer Van Allen belt during an acceleration event.

Although the outer ring displayed its characteristic inconstancy, the new middle ring barely budged for nearly four weeks. Then a shock wave, probably linked to a burst of solar activity, wiped it out in less than an hour on 1 October.

Spacecraft malfunctions

It's not clear where the middle ring came from, Baker says, although it was probably related to the acceleration event. The electrons could have been stripped from the outer Van Allen belt, funnelled back towards the Earth and got trapped in the middle on the way, or they could have been energised from closer to Earth and shot up to higher altitudes.

Figuring out what happened could be important to protecting spacecraft from radiation damage, says Yuri Shprits of the University of California in Los Angeles, who was not involved in the observations but is crafting a theoretical explanation that he hopes to publish soon. "It truly presents us with a very important question, and very important puzzles," he says.

There were no specific spacecraft malfunctions during September that can be directly linked to the new belt, says Shprits. However satellite operators will want to know if such belts are common and if they pose more of a risk.

With no other examples of a transient belt caught so far, it's too soon to answer all those questions, Baker says. "We only have one in captivity," he says. "We're still trying to figure out exactly how it works."

Journal reference: Science, DOI: 10.1126/science.1233518

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Shark fin-hungry China drives "chaotic" fishing in Indonesia

BENOA, Indonesia: Dozens of weary Indonesian fishermen sail into a busy port on the resort island of Bali celebrating their lucrative and controversial haul that is destined to end up at Chinese banquets.

The fishermen show off about 100 shark fins, already sliced off the carcasses, that are ready to be sold to middle-men and then most likely onwards to mainland China or cities around the world with big Chinese populations.

"We don't only look for sharks -- we mainly catch tuna and marlin -- but finding sharks is a good bonus. Their fins are worth a lot and the meat is easy to sell locally," said 33-year-old Warsito, who goes by one name.

Fishermen around Bali sell shark fins fresh off the boat for between US$15 and US$50, helping to satiate an ancient but fast-growing Chinese appetite for soup in which it is the main ingredient.

Shark fin soup was once a delicacy for China's elite, but shark populations have been decimated around the world as the country's 1.3 billion people have grown wealthier and incorporated it into their festivities.

While the Chinese government has banned shark fin soup from state banquets, and some five-star restaurants in Hong Kong and Singapore have dropped it from their menus, a burgeoning middle class in China continues to stoke demand.

Humans kill about 100 million sharks each year, mostly for their fins, according to the UN Food and Agriculture Organisation (FAO), and conservationists are warning that dozens of species are under threat.

Ninety percent of the world's sharks have disappeared over the past 100 years, mostly because of overfishing in countries such as Indonesia, the FAO said.

Conservationists also point out that "finning" -- slicing the valuable fins from live sharks -- is simply inhumane, as the rest of the animal is typically dumped back into the ocean where it bleeds slowly to death.

How to save the shark will be a top concern at the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) that begins in Bangkok, Thailand, on Sunday.

World authorities will look at restricting trade of certain shark species.

Restrictions would apply to manta rays and five shark species -- the porbeagle, scalloped hammerhead, great hammerhead, smooth hammerhead and oceanic whitetip -- and must be approved by two-thirds of member states.

However, experts say laws to restrict trade will mean little unless there are total bans on fishing, with greater efforts needed to control unregulated fisheries.

Indonesia is particularly important because it is the world's biggest fisher and exporter of sharks, with thousands of small-time fishermen such as those in Bali able to operate with impunity.

Management of the Indonesian industry has been "total chaos", Conservation International Indonesia marine programme director Tiene Gunawan said, with no national restrictions on the trade.

In 2010, the Indonesian government designed a national plan of action to better manage the shark fishing industry, but it has so far issued no regulations.

Rampant shark fishing has already affected ecosystems in Indonesian waters, Gunawan said, including the world-famous diving spot Raja Amapat in the region of Papua.

However recent efforts by the provincial authorities there -- emanating from a recognition that there is greater economic benefit in maintaining shark populations -- could be a model for the future.

After authorities in Raja Ampat noticed a surge in boats carrying hundreds of shark fins but no carcasses, the local government banned shark fishing in 2010.

Last week the ban was made into law, creating the country's only shark and manta ray sanctuary. It is also the first in the Coral Triangle, a massive region in Southeast Asia known as the "Amazon of the ocean".

"What they realised, and our studies support this, is that the value of a dead shark is much lower than if we keep it alive for tourism," Gunawan said.

-AFP/fl

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Movie studios target mobile apps for copyright infringement

Google Play app store.

(Credit:
Screenshot by Dara Kerr/CNET)

After targeting Web sites for copyright infringement for years, Hollywood is now setting its sights on mobile apps, according to Reuters.

Time Warner, Walt Disney, Sony, Viacom, and Twentieth Century Fox have all recently sent app "take down" notices to Google. Citing copyright infringement, these studios are demanding that the Web giant remove apps that use the likeness of characters in their movies or TV shows.

One of the offending apps is "Hobbit 3D Wallpaper HD," which has images from the popular movie, according to Reuters. Other apps are from movies like "Clash of the Titans," "Spiderman," and "Green Lantern."

The app market is a lucrative one. According to Reuters, it's worth $20 billion as of this year. Also, many of these apps get away without paying licensing fees.

"Smartphone apps that provide a direct link to infringing content have become a growing problem that needs to be addressed," Motion Picture Association of America's senior vice president for Internet content protection Marc Miller told Reuters. "Not only do these apps offer access to creative content that has been illegally copied, but they also pose risks to consumers from malware and often fail to provide viewers with the quality product they could often get through a growing number of legitimate sources."

According to Reuters, Google is complying with the studios' requests and is removing many of these apps from its Google Play app store. An Apple spokesperson wouldn't comment on take down notices for Reuters but did say that it reviews all apps before offering them in its App Store.

Over the past few years, Google has continually made more concessions to copyright owners, who have long demanded that it take steps to prevent copyright infringement. And, in August, it took action that was among the most significant antipiracy measures the company has ever adopted by penalizing sites that generated many complaints from copyright owners.

It's unclear if the Web giant has taken additional measures to curb copyright infringement on apps in Google Play.

CNET contacted Google and Apple for comment. We'll update the story when we get more information.

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Scarred Duckbill Dinosaur Escaped T. Rex Attack

A scar on the face of a duckbill dinosaur received after a close encounter with a Tyrannosaurus rex is the first clear case of a healed dinosaur wound, scientists say.

The finding, detailed in the current issue of the journal Cretaceous Research, also reveals that the healing properties of dinosaur skin were likely very similar to that of modern reptiles.

The lucky dinosaur was an adult Edmontosaurus annectens, a species of duckbill dinosaur that lived in what is today the Hell Creek region of South Dakota about 65 to 67 million years ago. (Explore a prehistoric time line.)

A teardrop-shaped patch of fossilized skin about 5 by 5 inches (12 by 14 centimeters) that was discovered with the creature's bones and is thought to have come from above its right eye, includes an oval-shaped section that is incongruous with the surrounding skin. (Related: "'Dinosaur Mummy' Found; Have Intact Skin, Tissue.")

Bruce Rothschild, a professor of medicine at the University of Kansas and Northeast Ohio Medical University, said the first time he laid eyes on it, it was "quite clear" to him that he was looking at an old wound.

"That was unequivocal," said Rothschild, who is a co-author of the new study.

A Terrible Attacker

The skull of the scarred Edmontosaurus also showed signs of trauma, and from the size and shape of the marks on the bone, Rothschild and fellow co-author Robert DePalma, a paleontologist at the Palm Beach Museum of Natural History in Florida, speculate the creature was attacked by a T. rex.

It's likely, though still unproven, that both the skin wound and the skull injury were sustained during the same attack, the scientists say. The wound "was large enough to have been a claw or a tooth," Rothschild said.

Rothschild and DePalma also compared the dinosaur wound to healed wounds on modern reptiles, including iguanas, and found the scar patterns to be nearly identical.

It isn't surprising that the wounds would be similar, said paleontologist David Burnham of the University of Kansas Biodiversity Institute, since dinosaurs and lizards are distant cousins.

"That's kind of what we would expect," said Burnham, who was not involved in the study. "It's what makes evolution work—that we can depend on this."

Dog-Eat-Dog

Phil Bell, a paleontologist with the Pipestone Creek Dinosaur Initiative in Canada who also was not involved in the research, called the Edmontosaurus fossil "a really nicely preserved animal with a very obvious scar."

He's not convinced, however, that it was caused by a predator attack. The size of the scar is relatively small, Bell said, and would also be consistent with the skin being pierced in some other accident such as a fall.

"But certainly the marks that you see on the skull, those are [more consistent] with Tyrannosaur-bitten bones," he added.

Prior to the discovery, scientists knew of one other case of a dinosaur wound. But in that instance, it was an unhealed wound that scientists think was inflicted by scavengers after the creature was already dead.

It's very likely that this particular Edmontosaurus wasn't the only dinosaur to sport scars, whether from battle wounds or accidents, Bell added.

"I would imagine just about every dinosaur walking around had similar scars," he said. (Read about "Extreme Dinosaurs" in National Geographic magazine.)

"Tigers and lions have scarred noses, and great white sharks have got dings on their noses and nips taken out of their fins. It's a dog-eat-dog world out there, and [Edmontosaurus was] unfortunately in the line of fire from some pretty big and nasty predators ... This one was just lucky to get away."

Mysterious Escape

Just how Edmontosaurus survived a T. rex attack is still unclear. "Escape from a T. rex is something that we wouldn't think would happen," Burnham said.

Duckbill dinosaurs, also known as Hadrosaurs, were not without defenses. Edmontosaurus, for example, grew up to 30 feet (9 meters) in length, and could swipe its hefty tail or kick its legs to fell predators.

Furthermore, they were fast. "Hadrosaurs like Edmontosaurus had very powerful [running] muscles, which would have made them difficult to catch once they'd taken flight," Bell said.

Duckbills were also herd animals, so maybe this one escaped with help from neighbors. Or perhaps the T. rex that attacked it was young. "There's something surrounding this case that we don't know yet," Burnham said.

Figuring out the details of the story is part of what makes paleontology exciting, he added. "We construct past lives. We can go back into a day in the life of this animal and talk about an attack and [about] it getting away. That's pretty cool."

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Arias Recounts Each Moment of Stabbing, Slashing

Accused murderer Jodi Arias was forced to recount today each detail of how she killed her ex-boyfriend, Travis Alexander, including re-enacting how he allegedly tackled her when she shot him, leaving her crying in her hands on the witness stand.

During hours of dramatic cross-examination by prosecutor Juan Martinez, Arias bawled as he asked her about stabbing, slashing and shooting Alexander on June 4, 2008.

"You would acknowledge that Mr. Alexander was stabbed, and that the stabbing was with the knife, and it was after the shooting according to you, right?" Martinez said in rapid succession.

"Yes, I don't remember," Arias said, covering her face with her hands.

"Do you acknowledge the stab wounds, and we can count them together, were to the back of the head and the torso?" Martinez said, flashing a photo of Alexander's bloodied body onto the courtroom projector. " Do you want to take a look at the photo?"

Arias, burying her face in her hands and shutting her eyes on the stand, mumbled, "No."

Alexander's sisters, seated in the front row of the gallery, also looked away, crying.

Arias, 32, is accused of killing Alexander on June 4, 2008 out of jealousy. He was stabbed 27 times, his throat was slashed and he was shot in the head twice.

Arias claims she killed in self-defense after Alexander had become increasingly violent with her. She could face the death penalty if convicted.

Martinez also forced Arias to demonstrate in court today how she claims Alexander lunged at her "like a linebacker," causing her to fire the gun at him. The pair argued over how exactly Alexander was positioned, and Martinez pushed her to explain what she meant.

"He lunges at me like a linebacker," Arias said.

"Like a linebacker, what does that mean?" Martinez asked.

Jodi Arias Under Attack in Third Day of Cross-Examination Watch Video

Jodi Arias, Prosecutor Butt Heads in Cross-Examination Watch Video

Jodi Arias Maintains She 'Felt Like a Prostitute' Watch Video

"He was low. It was almost like he dove," she said, and trying to explain it further, added, "He was like a linebacker is the only way I can describe it unless I get up to act it out which I'd rather not do."

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

Timeline of the Jodi Arias Trial

"Go ahead and do it," Martinez said. "Just stand. Go ahead."

Judge Sherry Stephens initially cleared the court as Arias demonstrated and then Martinez had her do it again after the jury and spectators were allowed back into the courtroom.

Standing and moving away from the witness box, Arias bent at the waist and spread out her arms and meekly made a slight lunging motion.

According to her testimony, Arias fired the gun as Alexander rushed at her, tackling her to the ground. She said she does not remember how she stabbed or slashed him.

It was a day of dramatics and anger as the prosecution pressed Arias on the details of the killing, with Martinez ending the afternoon of questioning by accusing Arias of lying throughout her direct testimony.

At one point Arias dissolved into tears, unable to answer pointed questions when shown a photo of Alexander's body lying crumpled in the bottom of the stall shower.

After a short pause, Martinez asked dryly, "Were you crying when you were shooting him?"

"I don't remember," Arias moaned.

"Were you crying when you stabbed him?" he said. "How about when you slashed his throat?"

"I don't remember, I don't know."

Martinez pressed on, "You're the one that did this right? And lied about all this right?"

"Yes."

"So then take a look at it," he barked.

Arias did not answer Martinez's question, crying into her hands instead. The judge, after a moment, called for the lunch recess to take a break from the testimony. Arias' attorney walked over and consoled her, telling her to "take a moment."

Until that moment, Arias had given vague answers to Martinez as he asked about the hours leading up to the murder. Arias, 32, has testified that she drove to Alexander's house on June 4, 2008, for a sexual liaison, that she had sex with Alexander and the pair took nude photos before an explosive confrontation ended with her killing him. She claims she doesn't remember stabbing Alexander, but insists it was in self-defense.

Martinez questioned her claims, asking exactly what they argued about and who encouraged whom to take the nude photos. He pointed out that Arias told Detective Esteban Flores of the Mesa police department that she had to convince Alexander to take the nude photos in the shower, but that she testified on the stand that Alexander had wanted them.

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Quantum skyfall puts Einstein's gravity to the test

DIVIDING a falling cloud of frozen atoms sounds like an exotic weather experiment. In fact, it's the latest way to probe whether tiny objects obey Einstein's theory of general relativity, our leading explanation for gravity.

General relativity is based on the equivalence principle, which says that in free fall, all objects fall at the same rate, whatever their mass, provided the only force at work is gravity. That has been proven for large objects: legend has it that Galileo did it first by dropping various balls from the Tower of Pisa. Whether equivalence holds at quantum scales, where gravity's effects are not well understood, isn't clear. Figuring it out could help create a quantum theory of gravity, one of the biggest goals of modern physics.

Creating a quantum equivalent of Galileo's test isn't easy. In 2010 a team led by Ernst Rasel of the University of Hannover in Germany monitored a quantum object in free fall, by tossing a Bose-Einstein condensate (BEC) – a cloud of chilled atoms that behaves as a single quantum object and so is both particle and wave – down a 110-metre tall tower. Now they have split and recombined the wave – all before the BEC, made of rubidium atoms, reached the bottom. This produces an interference pattern that records the path of the falling atoms and can be used to calculate their acceleration (Physical Review Letters, doi.org/km6). The next step is to do the same experiment on a different kind of atom, with a different mass, to see if the equivalence principle holds.

The BEC can only be split for 100 milliseconds in the tower before hitting the bottom, so to allow tiny differences between the atom types to emerge, the work must be repeated in space, where the waves can be split for longer. By showing that a matter-wave can be split and recombined while falling, Rasel's result is a "major step" towards the space version, says Charles Wang of the University of Aberdeen, UK.

This article appeared in print under the headline "Quantum skyfall tests Einstein's gravity"

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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Yvonne Lim: Making time for love

SINGAPORE: Her eyes glistened with tears when Singapore actress Yvonne Lim spoke about her character Liu Xixi in the upcoming drama "Marry Me", during a recent media event.

In the show, Liu, a successful gynecologist, winds up getting dumped by her boyfriend of 20 years, after she spent too much time on her career and neglected their relationship.

Lim revealed that she became emotional as her character's painful experiences in "Marry Me" reminded her of own.

"I have all these experiences before."

"I spend so much of my time on my work that I end up spending very little time dealing with matters of the heart," said Lim, explaining that she once broke up with a guy over the same issue.

"I remember I was very emotional when I read the script."

"I know how this character feels, why she struggles with her feelings, and why she is in pain, but keeps it bottled up inside."

Lim expressed that Liu is a character many women can identify with, because what happens to her in the show is something that also occurs in real life.

"She is so dedicated to her work that she forgot about her love life and kind of took it for granted.

"I've seen that happen to my girl friends. I have seen that happen to other people. I've heard stories like that before."

"When things drag on for too long, it (the relationship) gets stagnant. That's when things happen," said Lim earnestly.

Still, Lim said she prefers to take her time to slowly get to know someone instead of rushing things, and said she believes in "letting nature take its course".

"You have to find the right partner who is willing to be with you.

"If it happens, it happens. If not, that's the way it is," said Lim with a smile.

"I don't think about it much, though there is still this part of me that hopes for a fairytale ending."

"Marry Me", which also stars Koh Ya Hui and Jesseca Liu, airs every Wednesday, Thursday and Friday, 8pm on Channel U.

-CNA/ha

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Urine sample app lets users detect diseases with iPhones

The Uchek app lets users take urine samples with their smartphones.

(Credit:
Uchek)

Ever thought a smartphone could detect what was in your urine? Well, now it can. A new iPhone app developed by MIT entrepreneur Myshkin Ingawale, unveiled at the TED conference this week lets people take urine samples with their mobile device.

Obviously, pee and electronics don't mix, so this app instead uses the smartphone's camera to determine what's in urine. Dubbed Uchek, the app involves the user peeing into a cup, putting a color-coded urinalysis strip into the cup, taking of photo of the results, and then letting the app work its magic.

Uchek can detect up to 25 diseases, such as diabetes, urinary tract infections, and pre-clampsia. It can also measure the levels of glucose, proteins, ketones, and more. According to Wired, 1,200 sample tests showed that the app was more accurate than humans interpreting the color-coded strips.

Ingawale's goal is to help people become more aware of what health issues they might have or track their existing conditions. Ideally, it would be extra information to give to a doctor.

"The idea is to get people closer to their own information," Ingawale said at the TED conference, according to Wired. "I want people to better understand what is going on with their bodies."

Uchek is currently working its way through Apple's approval process and Ingawale is also working on an
Android app, according to Wired. The app will cost 99 cents and users can buy a packet of strips and a color-coded user guide for $20.

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Why African Rhinos Are Facing a Crisis

The body count for African rhinos killed for their horns is approaching crisis proportions, according to the latest figures released by the International Union for Conservation of Nature (IUCN).

To National Geographic reporter Peter Gwin, the dire numbers—a rhinoceros slain every 11 minutes since the beginning of 2013—don't come as a surprise. "The killing will continue as long as criminal gangs know they can expect high profits for selling horns to Asian buyers," said Gwin, who wrote about the violent and illegal trade in rhino horn in the March 2012 issue of the magazine.

The recent surge in poaching has been fueled by a thriving market in Vietnam and China for rhino horn, used as a traditional medicine believed to cure everything from hangovers to cancer. Since 2011, at least 1,700 rhinos, or 7 percent of the total population, have been killed and their horns hacked off, according to the IUCN. More than two-thirds of the casualties occurred in South Africa, home to 73 percent of the world's wild rhinos. In Africa there are currently 5,055 black rhinos, listed as critically endangered by the IUCN, and 20,405 white rhinos. (From our blog: "South African Rhino Poaching Hits New High.")

Trying to snuff out poaching by itself won't work, said Gwin. The South African government is fighting a losing battle on the ground to gangs using helicopters, dart guns, high-powered weapons—and lots of money. (National Geographic pictures: The bloody poaching battle over rhino horn [contains graphic images].)

"Every year they get tougher on poaching, but rhino killings continue to rise astronomically," said Gwin. "Somehow they have to address the demand side in a meaningful way. This means either shutting down the Asian markets for rhino horn, or controversially, finding a way to sustainably harvest rhino horns, control their legal sale, and meet what appears to be a huge demand. Either will be a formidable endeavor."

Hope and Hurdles

The signing in December of a memorandum of understanding between South Africa and Vietnam to deal with rhino poaching and other conservation issues raises hope for some concrete action. Observers say the next step is for the two governments to follow through with tangible crime-stopping efforts such as intelligence sharing and other collaboration. The highest hurdle to stopping criminal trade, though, is cultural, Gwin believes. "In Vietnam and China, a lot of people simply believe that as a traditional cure, rhino horn works." (Related: "Blood Ivory.")

The recent climb in rhino deaths threatens what had been a conservation success story. Since 1995, due to better law enforcement, monitoring, and other actions, the overall rhino numbers have steadily risen. The poaching epidemic, the IUCN warns, could dramatically slow and possibly reverse population gains.

The population growth is also being stymied by South Africa's private game farmers, who breed rhinos for sport hunting and tourism and for many years have helped rebuild rhino numbers. Many of them are getting out of the business due to the high costs of security and other risks associated with the poaching invasions.

Those who still have rhinos on their farms will often pay a veterinarian to cut the horns off—under government supervision—to dissuade poachers, but the process costs more than $2,000 and has to be repeated when the horns grow back every two years. Even then the farmers are stuck with horns that are illegal to sell—and which criminals seek to obtain.

Room for Debate

Rhino killings and the trade in their horns will be a major topic at a high-profile conference, the 16th meeting of the Conference of the Parties to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which opens in Bangkok March 3. What won't surprise Gwin is if the issue of sustainably harvesting rhino horns from live animals comes up for discussion.

"It's an idea that seems to be gaining traction among some South African politicians and law enforcement circles," he said, noting that the international conservation community strongly opposes any talk of legalizing the trade of rhino horn, sustainably harvested or not. The bottom line for all parties in the discussion is clear, said Gwin: "The slaughter has to stop if rhinos are to survive."

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Arias Prosecutor Too Combative, Experts Say

He has barked, yelled, been sarcastic and demanded answers from accused murderer Jodi Arias this week.

And in doing so, prosecutor Juan Martinez and his aggressive antics may be turning off the jury he is hoping to convince that Arias killed her ex-boyfriend Travis Alexander in June 2008, experts told ABCNews.com today.

"Martinez is his own worst enemy," Mel McDonald, a prominent Phoenix defense attorney and former judge, told ABC News. "He takes it to the point where it's ad nauseam. You have difficulty recognizing when he's driving the point home because he's always angry and pushy and pacing around the courtroom. He loses the effectiveness, rather than build it up."

"He's like a rabid dog and believes you've got to go to everybody's throat," he said.

"If they convict her and give her death, they do it in spite of Juan, not because of him," McDonald added.

Martinez's needling style was on display again today as he pestered Arias to admit that she willingly participated in kinky sex with Alexander, though she previously testified that she only succumbed to his erotic fantasies to please him.

Arias, now 32, and Alexander, who was 27 at the time of his death, dated for a year and continued to sleep together for another year following their break-up.

Arias drove to his house in Mesa, Ariz., in June 2008, had sex with him, they took nude photos together and she killed him in his shower. She claims it was in self-defense. If convicted, Arias could face the death penalty.

Jodi Arias, Prosecutor Butt Heads in Cross-Examination Watch Video

Jodi Arias Maintains She 'Felt Like a Prostitute' Watch Video

Jodi Arias Admits to Killing Man, Lying to Police Watch Video

Martinez also attempted to point out inconsistencies in her story of the killing, bickering with her over details about her journey from Yreka, Calif., to Mesa, Ariz., including why she borrowed gas cans from an ex-boyfriend, when she allegedly took naps and got lost while driving, and why she spontaneously decided to visit Alexander at his home in Mesa for a sexual liaison.

"I want to know what you're talking about," Arias said to Martinez at one point.

"No, I'm asking you," he yelled.

Later, he bellowed, "Am I asking you if you're telling the truth?"

"I don't know," Arias said, firing back at him. "Are you?"

During three days of cross examining Arias this week, Martinez has spent hours going back and forth with the defendant over word choice, her memory, and her answers to his questions.

"Everyone who takes witness stand for defense is an enemy," McDonald said. "He prides himself on being able to work by rarely referring to his notes, but what he's giving up in that is that there's so much time he wastes on stupid comments. A lot of what I've heard is utterly objectionable."

Martinez's behavior has spurred frequent objections of "witness badgering" from Arias' attorney Kirk Nurmi, who at one point Tuesday stood up in court and appealed to the judge to have a conference with all of the attorneys before questioning continued. Judge Sherry Stephens at one point admonished Martinez and Arias for speaking over one another.

Andy Hill, a former spokesperson for the Phoenix police department, and Steven Pitt, a forensic psychiatrist who has testified as an expert witness at many trials in the Phoenix area, both said that despite his aggressive style, Martinez would likely succeed in obtaining a guilty verdict.

"When it comes to cross examination, one size does not fit all," said Pitt. "But if you set aside the incessant sparring, what the prosecutor I believe is effectively doing is pointing out the various inconsistencies in the defendant's version of events."

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