Most of us have lost our wallet at some stage in our lives. But few would imagine having it returned after 66 years. Edward Parker dropped his wallet in 1950 into an inaccessible spot behind a bookshelf, while working as an electrician, repairing World War Two bomb damage in the palace. The wallet stayed there until this year when a builder, doing some restoration work, finally found it.

    The wallet is a time capsule. Its leather and webbing has long ago started to disintegrate. But it contains numerous pictures of family, invoices, receipts, old union cards, results of a chest X-ray (sent to him in 1948, the same year as the NHS was founded), a national service card dated 9 December 1944 and a medical insurance card. His business cards—E Parker, Electrical Contractor—seem almost original. Reflecting the typical methods of contact of the time, they have an address but no telephone number.

    A month ago I was speaking to a press officer Lambeth Palace and he mentioned that the wallet had just been handed in. We thought it might be nice to try and work out whose it was and give it back to the family. Edward Parker is a pretty common name, but his medical card contained two places of residence—Poets Road and Springdale Road in north London. From this, Islington Council were able to find details of a marriage between Edward Parker and Constance Butler in 1947.

    That information was enough to work out that he was still alive and in a care home in Essex, so I went to visit him. Now 89, Edward has dementia (痴呆), but he was clearly happy to get the wallet and in particular, the photographs back. He pointed out pictures of his mother and father, his brother, his cousins and his wife Constance, who was with him when I visited. He hadn't seen a picture of his father since he lost the wallet, Constance, 90, said.

    Are you using a dating App to make friends? How do you know that Ben from London is really 25-year-old? Is his photo taken recently? Is his name even Ben? Dating apps can be tricky to operate, particularly when you're trying to know whether someone is trustworthy, but one thing you can't cheat is your gene, which is why a new dating app is using DNA as a basis for its match.

    A dating app named Pheramor requires all users to hand in a cheek sample, from which a team of in-house scientists using a specially-created tool can queue the specific genes connected with attraction and then identify which users might be suitable. The process works by separating the 11 genes that link to our pheromones（信息素）, the chemical signals that are believed to control one's attraction. Combining this data with the personal information allows the app to make very specific matches.

    “Pheramor uses both your biology and your social technology: we collect your genetic data through a cheek sample and collect your like, dislikes, and interest from your social media introductions like Facebook, Twitter, etc,” the app's website explains. “All of them will be used in our specific software, which is designed to learn what you prefer.”

    The co-founder Brittany Barreto, who has a PHD in genetics added that Pheramor's technology digs deeper than traditional dating apps, making it almost impossible for people to cheat their way to a date.

    The Houston-based app is already up and running but hopes to be officially put into market in February with 3,000 members.

    Our cities have never been denser, taller, or busier than they are now, and with that, comes the constant battle for land. But if we look at aerial images of any city center, we can quickly spot plenty of unused space — the rooftops.

    So what can we use this precious resource for? In a growing number of high-density cities, some of it is dedicated to recreation — everything from bars and pools, to soccer pitches and running tracks can now be found atop skyscrapers. But when a rooftop offers access to sunlight, there are two more obvious candidates for its use - agriculture and solar power.

    Green roofs have been growing in popularity for more than a decade, and in some cases, growing in scale too. Green roofs can provide a habitat for birds and insects in an otherwise hostile environment.

    Cities can be several degrees warmer than the surrounding countryside. Green roofs come with the added benefit of mitigating the dreaded urban heat island effect. Trees and green spaces can absorb shortwave radiation, and use it to evaporate water from their leaves — a kind of 'double cooling' effect.

    With food security and urban nutrition ever-higher on the agenda for the United Nations, there's also a worldwide movement of using green roofs for hyper-local food production. In regions with suitable climates, hundreds of different vegetables, fruits, and salad leaves can be grown on rooftops.

    But what about solar power? With so many cities now stopping using fossil fuels, and the costs of solar panels dropping dramatically, PV systems have become the 'go to' option for generating distributed power in built-up areas. And, even with standard commercial panels, the energy gains are dramatic. It is estimated that rooftop PV systems could generate almost 40% of electricity demands nationwide.

    There's no doubt that in both cases, a network of 'productive rooftops' could benefit the local community by supplying a portion of a necessary resource — either food or electricity — while also reducing their environmental burden. But is one better than the other?

    This was the question posed by researchers from MIT and the University of Lisbon in a recent paper in the journal Cities. Focusing on the rooftops of a mixed-use neighborhood in Lisbon, they carried out a Cost-Benefit Analysis. Starting with existing data on everything from installation costs and resources used, to carbon footprint and yield, they modelled the impact that each installation would have on the local community over a period of 50 years.

    And by looking at it that way, they concluded that for Lisbon, the use of rooftops for food production could yield significantly higher local value than solar PV energy generation. Of course, this is very site-specific. There is no one-size-fits-all solution to make cities more sustainable, and anyone who tells you otherwise is massively over-simplifying a complex issue. Now, all I hope is that some of those decision makers start using it.

    On Thursday night my two adult children took us out to dinner as our daughter lives in Bathurst and she will be there for Father's Day with her husband's side of the family. Two of our grandchildren were able to join us.

    Having pre-celebrated my Father's Day and it being on our minds, my wife asked this question only this morning:

    "Do you remember anything about your father?"

    While this subject had come up before, however, the question had not been put so bluntly(直率的). I answered "No. My only memory is of the few photos outside." You see, my father died when I was only four years old.

    Many people have lost their father early in life and it is easy to feel somewhat sorry for having to deal with such a situation, especially when the death has occurred when you are at an early age. On reflection, I think I do not remember anything because he passed away when he was a member of the Royal Australian Air Force. He was a Corporal(下士) doing land based duties, however, a medical condition took his life. It was 1942.

    The 2nd World War was in full battle and Australia was being attacked. My Mum and I with my younger brother, were living with my grandparents and I can only imagine the emotional circumstances that existed in the household at that time. Probably not something that would leave a memory.

    What I would like to say at this time, as the question is often asked, "What did you learn from your father?" The thing I learnt from his passing, at the age of 28, is a love of life. What I do remember is growing up wondering if I would live to his age, and after I did, thinking each year the bonus(津贴) of life I had been blessed with when compared to my father.

    I have sometimes felt disappointment in not knowing my father but life has moved on. However, can I say to those who do have fathers, celebrate today with him and return him all the love and happiness he has given to you.

    Moving smoothly and silently through Alibaba Group Holding Ltd's futuristic "FlyZoo" hotel, black disc-shaped robots about a metre in height deliver food and drop off fresh towels.

    The robots are part of a set of high-tech tools that Alibaba says strongly cuts the hotel's cost of human labour and eliminates the need for guests to interact with other people.

    Formally opened to the public last month, the 290-room FlyZoo is an incubator for technology Alibaba wants to sell to the hotel industry in the future and an opportunity to showcase its prowess in artificial intelligence. It is also an experiment that tests consumer comfort levels with unmanned commerce in China.

    Inside the hotel, softly-lit white panelled walls bring to mind the interiors of Hollywood spaceships. Guests check in at podiums that scan their faces, as well as passports or other ID. Visitors with a Chinese national ID can scan their faces using their smartphones to check in ahead of time.

    Elevators scan guests' faces again to verify which floor they can access and hotel room doors are opened with another face scan.

    "It's very quick and safe. I haven't used it much yet, but basically, I can be in my room in one minute, "said guest Tracy Li. Li added that safety was one of her priorities and she was pleased her room could only be entered with a scan of her face.

    In the rooms, Alibaba's voice command technology is used to change the temperature, close the curtains, adjust the lighting and order room service.

    At the hotel's restaurant, taller capsule-shaped robots deliver food that guests have ordered via the FlyZoo app while at a separate bar, a large robotic arm can mix more than 20 different types of cocktails. Facial recognition cameras add charges to the room rate automatically.

    The hotel does employ humans, though Alibaba declined to detail how many. This includes chefs and cleaners as well as reception staff, who will assist with conventional check-in procedures for guests unwilling to have their faces scanned and want to use electronic key cards.

The following are reviews of four films.

Happiness(Romance)★★★

Happiness tells the story of two people who work for different advertising companies. They talk on the phone all the time and don't like each other. But then they correspond by email and fall in love. This movie is very popular with teenagers and people who like romances. It also has beautiful music.

I Scream(Thriller)★★

In I Scream,Paul is a young man who joins a thriller club. Each of the members tries to frighten the others. Paul is told to stay in an old house for the night. Everyone who has tried to stay in the house before has died. This movie is very frightening but also quite silly. It doesn't make sense for Paul to stay in the house when things start to go wrong. It is only for people who like thrillers.

Paul's Heroes(Comedy)★★★

This is a very funny war movie set in World WarⅡ. Six soldiers have to get to Italy to take secret messages to the American army there. In the movie, they dress up as women and fight with Italian workers. You can guess the ending, but it's great fun getting there.

____ (Drama)★★★★

This is a very good drama with Jack Ross, who plays a hardworking truck driver. His wife becomes ill and he has to find a doctor who can help her. In his travels he meets Dr Lloyd (Phil Driver) who has found the cure for the illness, but Jack Ross has only twelve hours to get the medicine back to his wife on the other side of America. This is an excellent movie, which is very exciting.