To understand how bacteria and viruses work and test potential treatments, scientists study them in animals. But what about diseases that only affect humans? A group out of La Jolla’s Salk Institute has worked around that problem with a compromise—a mouse with a human liver.

"We needed a human liver in a mouse as a tool to study hepatitis B and C viruses, which are totally human hepatotropic—meaning they only infect human cells," explained Inder Verma, senior author of the study published February 22 in the Journal of Clinical Investigation. "It would be nice if we could study hepatitis in a culture dish, but unfortunately [liver cells] lose their properties in vitro."

In 2007, the team published a study in Proceedings of the National Academy of Sciences that showed they could replace some of a mouse’s liver cells with human hepatocytes. The present study went one step further—they could replace enough cells to cause widespread hepatitis (inflammation of the liver) after exposure to the virus. They also showed that conventional antiviral drugs could help clear the hepatitis infection in the chimeric mice.

The researchers say the model will allow them to screen new antiviral therapies. "The current state-of-the-art treatment for hepatitis C is pegylated interferon and ribaviron, which has a success rate of 40-80 percent," says the study's lead author Karl-Dimiter Bissig. He adds that the prevalence of resistant genotypes in the U.S. brings the success rate closer to 50 percent. "There are a lot of patients that retain the virus after therapy," he says. Furthermore, the therapy is very long and painful, often making patients ill throughout the six-month treatment. "There is room for more effective therapies that are better tolerated by patients. We can use this model for preclinical assessment of potential drugs," he says.

The most serious consequence of hepatitis B and C infection in humans is liver cancer. But unlike humans, the infected chimeric mice showed no signs of cancer despite being particularly susceptible to tumor formation because of the immunosuppression that allowed them to accept the human cell transplant. "We thought we would see tumors because they’re immunosuppressed, but we didn’t," says Verma. "In humans it takes years to develop carcinoma," he says, explaining that perhaps the two-year lifespan of the mouse isn’t long enough to see these effects.

The team plans to soon use the model to see whether they can generate organs using transplanted embryonic and induced pluripotent stem cells rather than mature liver cells. They will also collaborate with researchers at the University of California in San Diego to study other pathogens that require a human host, such as malaria.

The first post-GFC supercar has broken cover in the form of the $1 million-plus Porsche 918 Spyder that’s tipped to go on sale as the flagship of the sports car maker’s range.

The Porsche 918 Spyder is powered by a hybrid drivetrain that delivers almost as much power as a modern Formula One car, accelerating the two-seat drop-top to 100km/h in 3.2 seconds on the way to a top speed of 320km/h.

Despite its explosive performance the Porsche 918 Spyder is claimed to use an average of 3.0 litres of fuel per 100km, or 23 per cent less than the Toyota Prius.

Porsche says the 918 Spyder is a car with “extremely low fuel consumption, supreme performance and long electric range” representing “an essential milestone in Porsche’s strategy on the way to genuine electro-mobility”.

“Electric cars will be important in the future for sports cars,” says Porsche boss Michael Macht.

The recently installed head of Germany’s famous sports car maker says the 918 Spyder has typical Porsche genes and that there’s a strong chance the company will put it into production.
“Porsche has never shown a concept car that wasn’t built. Let’s wait and see what the reaction in Geneva [at motor show] is.”

The 918 Spyder borrows its 3.4-litre V8 engine from the Porsche RS Spyder Le Mans race car. On its own the engine makes about 375kW. However, in the Porsche 918 Spyder concept the V8 is teamed with three electric motors, which can boost power a further 160kW, taking overall output to about 540kW.

Electrical energy can be generated either by the Lithium-ion battery – which can also be recharged in a regular powerpoint – or a giant flywheel that can convert the kinetic energy that would normally be lost in heat through the brakes.

The 918 Spyder has four different modes, including one that allows the car to be driven for up to 25km as a pure electric vehicle. There are three other modes – Hybrid, Sport Hybrid and Race Hybrid – which use the V8 engine and electric motors for varying levels of performance and power.

A button on the steering wheel allows the driver to choose between the four modes. Porsche says the 918 Spyder is the fastest road car it has built to lap the infamous Nurburgring race track, with a claimed time less than 7 minutes 30 seconds.

The Porsche 918 Spyder also has retractable air intakes designed to improve aerodynamics and shove air into the engine under pressure for increased power, as well as an adjustable rear wing. The Porsche 918 Spyder is the latest supercar concept to showcase hybrid technology as a way to boost performance and use less fuel.

BMW last year showed its three-cylinder Vision Efficient Dynamics concept car, a vehicle the company said could accelerate to 100km /h in 4.8 seconds and use just 3.8L/100km.

Ferrari will also show its 599 Hybrid car, a version of which is expected to go into production about 2014. However, while Ferrari has confirmed it is developing a million-dollar-plus supercar to effectively replace the Enzo, it is at least two years away with scant details available.

The Porsche 918 Spyder is seen as a successor to the Porsche Carrera GT that was only ever sold as a left-hand-drive model. Porsche has not confirmed whether the 918 Spyder will be built in right-hand drive to make it suitable for markets such as Australia.

Porsche is working on a range of petrol-electric hybrid cars as well as an electric sports car in an effort to reduce fuel use and meet demand for more efficient vehicles.

Coffee chain Starbucks Corp. is sticking to its policy of letting customers carry guns where it's legal and said it does not want to be put in the middle of a larger gun-control debate.

The company's statement, issued Wednesday, stems from recent campaign by some gun owners, who have walked into Starbucks and other businesses to test state laws that allow gun owners to carry weapons openly in public places. Gun control advocates have protested.

The fight began heating up in January in Northern California and has since spread to other states and other companies, bolstered by the pro-gun group OpenCarry.org.

Some of the events were spontaneous, with just one or two gun owners walking into a store. Others were organized parades of dozens of gun owners walking into restaurants with their firearms proudly at their sides.

Now, gun control advocates are protesting the policy. The Brady Campaign to Prevent Gun Violence, launched a petition drive demanding that the company "offer espresso shots, not gunshots" and declare its coffeehouses "gun-free zones." And Wednesday, that group planned to deliver 28,000 signatures to the coffee giant's headquarters in Seattle.

The group also held a press conference near Seattle's Pike Place Market, just a few yards away from where the first Starbucks cafe opened. Gun rights advocates showed up as well, some carrying handguns in holsters around their waists.

Brian Malte of the Brady Campaign said carrying guns intimidates and frightens people, and said the group thinks Starbucks will "do the right thing" and change its policy.

"They're putting their workers in harm's way by allowing people to carry guns into their stores, especially open carry," Malte said.

More than a dozen pro-gun supporters, some with Starbucks coffee cups in hand, chanted during the press conference, at points interrupting speakers.

"I think the (Brady campaign is) trying to strong-arm private businesses into banning the rights of the people," said Bev Carman of Everett, Wash. Carman held a sign that said: "Criminal Control not Gun Control."

Businesses can choose to ban guns from their premises. And Starbucks said Wednesday that it complies with local laws in the 43 states that have open-carry weapon laws.

"Were we to adopt a policy different from local laws allowing open carry, we would be forced to require our partners to ask law abiding customers to leave our stores, putting our partners in an unfair and potentially unsafe position," the company said in its statement.

It said security measures are in place for any "threatening situation" that might occur in stores.

Starbucks asked both gun enthusiasts and gun-control advocates "to refrain from putting Starbucks or our partners into the middle of this divisive issue."

Starbucks shares rose a penny to $23.34 in midday trading Wednesday.

Citroen sprung one of the few real surprises of Geneva's opening press day when it revealed the Survolt sports car. An unashamedly out-there coupe with no confirmed production aspirations - or engine for that matter - the Survolt is designed to appeal particularly to women. Oh how French!

"We wanted to make the sporty car but with the more sensual touch to it," Citroen head of project design Bertrand Dantec told Drive. "That's why we have the pink colour scheme."

Dantec is only new to Citroen, having transferred across the aisle from fellow PSA brand Peugeot, where he designed the RCZ show car and several other concepts.

However, he said the design brief for the Survolt was "a dream": "We have no constraints so we have more creativity."

But all that creativity appears to have resulted in a miniaturised version of the W16 Bugatti Veyron supercar. It's a visual alignment that Dantec says is accidental but not offensive.

"You are not the first to notice the similarity," he said. "It's a good comparison but it's not intentional."

"We have an idea, we want the car to fit like a tailored suit and after when we see the car we say 'oh Bugatti'. That's not the intention.

"It is not intended to have supercar performance, but the sensation or feeling of a fast car. For us it's not a supercar, it's a feeling of well-being."

Citroen revealed very little about the Survolt apart from its compact measurements - 3.85 m long, 1.87 m wide and 1.20 m high. A four-page press release shed little more except for hyperbole.

For instance, the Survolt is described as having electric power but there is no explanation of the drivetrain. In reality, as confirmed by Dantec, the only way the car currently moves is by being pushed.

The Survolt is also meant to be a styling relation of the Revolte concept first shown at the Frankfurt show last year. However, apart from the grille, headlights, tail-lights, the extravagant cut through the door sheetmetal and some carbon-fibre trimmings there is little similarity.

But Dantec says that's the point of Citroen, a company which he insists has now reclaimed its styling mojo after decades of decline.

"Citroen dares, we dare to innovate again. All Citroens are different; each Citroen is an innovation in design for us. This project is different to this one; it's not like Audi with everything similar."

Dantec's claim was backed up by the other fresh displays on the Citroen stand, the DS3 Racing and the DS High Rider. The Racing is the hot hatch version of the new DS3 luxury mini that will be the basis for WRC star Sebastian Loeb's next racer. Just 1000 will be built with Australian numbers yet to be confirmed.

The High Rider is the DS version of the next generation Citroen C4 and is expected to trade in the concept's three doors for five. The cross-over stance is expected to be retained. Look for it in 2011.

A multinational, robotic air corps is quietly invading the polar regions of the earth. Some catapult from ships; some launch from running pickup trucks; and some take off the old-fashioned way, from icy airstrips. The aircraft range from remote-controlled propeller planes—of the type found at Toys “R” Us—to sophisticated, high-altitude jets. All are specially outfitted, not with weapons but with scientific instruments.

Unmanned aircraft have made headlines in the mountains of Afghanistan, but the technology has quickly trickled down to scientists seeking a less expensive, safer way to study the earth’s poles. Researchers have begun to put unmanned aerial systems, or UASs, to a variety of tasks, from monitoring the ozone layer to counting seal populations. Thanks to lower costs and improved technologies, “it’s absolutely exploded in the past couple of years,” says Elizabeth Weatherhead, who is an environmental scientist at the University of Colorado at Boulder.

The planes can be loaded with a variety of instruments, from radar (or lidar, the laser-based version) to chemical analysis tools and infrared sensors; some simply carry cameras. Last summer Weatherhead counted at least six different teams of scientists using UASs on a single Norwegian island. Her own group used a converted reconnaissance drone in two different Greenland missions. One mission was to count ice seal populations; another was to map melt ponds to help explain “why the edges of Greenland are melting so quickly,” she says. The team’s small UAS surveyed two melt ponds in a few days, Weatherhead says. “That’s something that previously would have taken researchers weeks for a single lake.”

Many of the aircraft cost several millions of dollars and are not exactly expendable. But at least if one goes down, there’s no loss of human life: polar crashes are “often beyond rescue capabilities,” Weatherhead says.

Some teams have learned to design and build their own aircraft. Richard Hale of the University of Kansas’s Center for Remote Sensing of Ice Sheets was in Antarctica this austral summer to test the Meridian, a new, single-prop unmanned plane built by a team mostly of Kansas students. The half-ton UAS, with a wingspan of eight meters and a range of 1,750 kilometers, will conduct radar surveys of the ice masses and of the underlying land.

Many of the planes fly preprogrammed routes by autopilot and are only remotely controlled for takeoff and landing (although some small ones are clotheslined by a strong wire). Small UASs are fuel-efficient, which is especially important in a place like Antarctica, where all the fuel has to be flown in at great expense. “We burn 1/20th of the fuel” of a conventional airplane, Hale said in January, speaking over a satellite link from the National Science Foundation’s McMurdo Station.

In an age of constant satellite surveys, airplanes are still necessary. They can, for example, “map the ice sheet at a resolution that modelers can use to really understand the dangers we’re seeing,” explains atmospheric scientist David Braaten of the University of Kansas. Braaten was a member of a team last year that mapped the Gamburtsev Mountains in Antarctica, a chain the size of the Alps buried under thousands of meters of ice. That survey was done with radar mounted on an ordinary twin-engine propeller airplane based in East Antarctica. (Robin Bell of Columbia University’s Lamont-Doherty Earth Observatory chronicled the effort in her blog on ScientificAmerican.com.) If a UAS had been available at the time, that project might have been “a lot cheaper,” Braaten figures.

Even better, a UAS with a long enough range could survey Antarctica while being based in Chile. This possibility may actually become true in the next few years. In October, NASA conducted the first test flights of its newly acquired Northrop Grumman RQ-4 Global Hawk, a jet-powered drone that can fly at altitudes up to 65,000 feet (where it can avoid the rough weather of polar regions) for more than 31 hours at a time. It can literally fly to the other end of the earth on a single tank of fuel.

“Apakah saya masih menikmati kehidupan yang saya jalani sekarang?” Sebuah pertanyaan yang sama, yang setiap pagi menjadi awal dari kehidupan seorang Doreen Westphal. Pertanyaan itu bagaikan sebuah system check. Sebuah sistem peringatan bagi diri sendiri sebelum ia memutuskan, apakah akan beralih ke proyek baru, ke studio baru, bahkan beringsut ke kota baru. Tentu saja keputusan itu akan diambil tatkala pertanyaan yang mengawali harinya itu lebih banyak terjawab, “No” – “Tidak”.

Doreen, berasal dari sebuah kota di bekas Jerman Timur yang kemudian memutuskan pindah ke Berlin untuk belajar menjahit. Perjalanannya berlanjut ke Nottingham di mana ia belajar desain panggung sebelum akhirnya menetapkan hati mendarat di Amsterdam. Di kota itu ia memulai pekerjaan sebagai perancang. Sebuah kerja kreatif. Doreen memilih Amsterdam karena, menurut dia, kota itu “ramai”, “seru”, “hidup”, “bergairah”.

Di studionya, di sebuah gedung bekas kantor pusat harian De Volkskrant, ia menganyam kreasi pada sebuah tas berbahan ban bekas dan kasur udara. Awalnya, secara iseng ia berkreasi, menjahit sendiri sebuah tas dari bahan tersebut di atas sebagai hadiah ulang tahun buat seorang teman. Teman ini, kemudian, kebetulan melintas di depan sebuah butik, dan ketika mata pemilik butik tertumbuk pada tas tadi, ia pun mengejar sang pemilik tas sambil bertanya, “Di mana saya bisa pesan tas seperti itu.” Bisa ditebak kelanjutannya. Itu hanya salah satu dari kreasi Doreen.

Demikian Majalah Der Spiegel edisi Agustus 2007 memotret Amsterdam sebagai salah satu kota kreatif dunia yang terus tumbuh. Kota ini giat membina aset ekonomi yang paling penting, yaitu kekuatan kreatif yang multikultur.

Doreen, dan pekerja kreatif lain di Amsterdam, menjadi bagian dari “kota yang seru” tadi, plus, ikut andil dalam membangkitkan ekonomi Amsterdam. Ia juga jadi bagian yang menghidupkan gedung tujuh lantai – Gedung Volkskrant – dari tahun 1960-an, di mana studionya berada. Sebuah gedung yang kemudian jadi penuh warna dengan para pelukis, tukang kayu, orang-orang dari studio berlabel hip hop yang semuanya mulai “menyembur”, menghembuskan sekumpulan asap dari lintingan ganja.

Bureau Broedplaatsen, dibentuk oleh pemerintah Kota Amsterdam, memantau gedung-gedung yang disewakan bagi pekerja kreatif – seperti Gedung Volkskrant – dan memberi subsidi untuk pemeliharaan. Hingga tahun 2007, kota sepeda ini sudah menggelontorkan 50 juta Euro (sekitar Rp 630 triliun- kurs Rp 12.600) untuk menumbuhkan kelas kreatif. Pertumbuhan di sektor individu pun luar biasa. Ada 8.000 orang bekerja di bisnis seni dan sektor jasa kreatif menciptakan 9.000 pekerjaan baru – dibandingkan 10 tahun sebelumnya, jumlah itu meningkat lebih dari sepertiganya. Sementara 12.000 orang bekerja penuh waktu di sektor media.

Pada situs resmi Bureau Broedplaatsen disebutkan, biro bentukan pemkot Amsterdam tadi bertugas mencari dan mengembangkan studio-studio, ruang hidup dan ruang kreatif yang terjangkau bagi para seniman dan pengusaha di bidang budaya. Tapi si biro tak memiliki studio atau ruang hidup dan ruang kreatif untuk disewakan.

Jalin, in Jantho district, Aceh Besar regency, has suddenly grabbed public attention for the last two weeks. The police have found training grounds used by armed terrorists, about 15 km east of Jantho city, the capital of Aceh Besar regency, or about 90 minutes to the east of Banda Aceh city.

Jalin is only a village at the end of the Jantho-Kemala road, near wooded hills. Most of the people there are transmigrants from other provinces. Some of the villagers are farmers who've been planting paddy and for the last one year trying to cultivate profit by seeding corn.

Last week, Jalin became 'famous' when a joint team of the Nanggroe Aceh Darussalam (NAD) mobile brigade police and the Aceh Besar district police apprehended four people there suspected to be linked with the Jamaah Islamiyah. The police stated that the group is linked with Muhammad Rois' group, which was responsible for the bombing at the Australian Embassy in 2004.

Rois is from Banten, and coincidentally two of the four people apprehended in Jalin are also from Banten. Jalin's terrain is hilly, it shares borders with three other regencies, and it's part of the Bukit Barisan mountain range.

In the last two days, the joint team with the Anti-terror squad Densus 88 have set up camp at Panca village, Seulawah valley, which is around the entrance point to the area suspected of being the training grounds of the armed terrorists.