After being delayed by a year due to the COVID-19 pandemic, Expo 2020 is underway in Dubai. From a 3D-printed sculpture of Michelangelo's David to a focus on sustainable technology, the first week has seen an eclectic mix. 

Close to 200 countries have chosen to participate in the world fair, hosting national themed exhibitions called pavilions. While some have opted for food, art and culture to draw in the crowds, others have focused on futuristic technology. 

China chose to combine the two with a nod to both a national symbol and hi-tech solutions. A robotic panda, capable of everything from dancing to shaking hands, welcomes visitors to China's pavilion.

Meanwhile, Singapore and the Netherlands are among those championing sustainability this week. The ethos of the Netherlands pavilion is about finding ways to produce water, energy and food in unison with one another.  

At the heart of the building is a giant cone-shaped vertical farm, growing a variety of vegetables. Niels Bouwman, the director of the Netherlands Pavilion, said they have 9,500 edible plants and extract "about 1,000 to 2,000 liters per day" of water from the humid Dubai desert using air filtration units on the roof. The design incorporates transparent solar panels on the ceiling, which Bouwman said "cover more than 40 percent" of the electricity needs at the pavilion.

Meanwhile, Singapore has built a mini rainforest in Dubai's hot desert climate. The aim is to prove that diverse ecosystems can be sustained using hi-tech solutions in even the harshest environments. The architects have built a pavilion that can sustain 80,000 plants from around 170 different species. Commissioner-General Yap Lay Bee said they "use the sun energy to draw up groundwater from within the pavilion. The water is then used back to irrigate the plants and meet the needs of the operations."

Italy's main attraction has been turning heads with a 3D printed version of Michelangelo's 16th Century marble statue of David. 

Paolo Glisenti, the Commissioner for Italian EXPO participation, said, "The reproduction was done with very sophisticated technology they use in space," before being "finished by artisans in Florence who covered the statue in marble powder." 

An Italian media report picked up by outlets around the world had alleged that certain parts of the sculpture were strategically hidden from public view owing to regional sensitivities. But the Italian pavilion rubbished the claim, saying nothing was censored and the artistic design always intended to give a different perspective of the masterpiece.

Expo 2020 is set to run for six months until March 2022. Occupying a 4.3 square kilometer site on the outskirts of Dubai, it cost $6.8 billion to build. Organizers hope it will attract around 25 million visits.