【推荐1】Sugar cane (甘蔗) contains around 10% sugar. But that means it contains around 90% non-sugar — the material known as bagasse (甘蔗渣) which remains once the sugar-bearing juice is squeezed out. World production of cane sugar was 185 million tonnes in 2017, which results in a lot of bagasse.

At the moment, most of it is burned. But Zhu Hongli, a mechanical engineer at Northeastern University, in Boston, thinks it can be put into better use. As she, and her colleagues describe, in Matter this week, with a bit of improving bagasse makes an excellent and biodegradable (可生 物降解的) replacement for the plastic used for disposable food containers such as coffee cups.

Dr. Zhu is not the first person to have this idea. But previous attempts tended not to survive contact with liquids. She knew from previous research that the main reason why past efforts fell to pieces when wet is that bagasse is composed of short fibres which are unable to hold the finished product. She therefore sought’ to insert a suitably long-fibred substance.       

Bamboo seemed to be the best choice. It grows quickly/degrades readily and has appropriately long fibres. And it worked. When the researchers blended bamboo remaining into bagasse, they found that the result had a   strong crossing of short and long fibres.

To put their new material through its paces, Dr. Zhu and her colleagues first poured hot oil onto it and found that, rather than passing through the material, as it would have with previous, bagasse products, the oil was resisted by their invention.

They also found that when they made a cup out of the stuff and filled it with water heated almost to boiling point, the cup remained unbroken for more than two hours. Though this is not as long as a plastic cup would last, it is long enough for all practical purposes.

【推荐2】HUNCH is designed to connect high school classrooms with NASA engineers. For the past two years, Gordon’s students have been studying ways to kill bacteria in zero gravity, and they think they’re close to a solution(解决方案). “We don’t give the students any breaks. They have to do it just like NASA engineers,” says Florence Gold, a project manager.

"There are no tests," Gordon says. "There is no graded homework. There almost are no grades, other than 'Are you working towards your goal?' Basically, it’s 'I’ve got to produce this product and then, at the end of year, present it to NASA.' Engineers come and really do an in-person review, and... it’s not a very nice thing at times. It’s a hard business review of your product."

【推荐3】A device that stops drivers from falling asleep at fine wheel is about to undergo testing at Department of Transport laboratories and could go on sale within 12 months.

The system, called Driver Alert, aims to reduce deadly road accidents by 20%-40% that are caused by tiredness. Airline pilots can also use it to reduce the 30% of all pilot-error accidents that are related to fatigue.

Driver Alert is based on a computerized wristband. The device, worn by drivers or pilots, gives out a sound about every four minutes during a car journey. After each sound the driver must respond by squeezing the steering wheel (方向盘). A sensor in the wristband detects this pressing action and measures the time between the sound, and the driver’s response.

Tiredness is directly related to a driver’s response time. Usually, a watchful driver would take about 400 milliseconds to respond but once that falls to more than 500 milliseconds, it suggests that the driver is getting sleepy.

In such cases the device gives out more regular and louder sounds, showing that the driver should open a window or stop for a rest. If the driver’s response continues to slow down, the sounds become more frequent until a nonstop alarm warns that the driver must stop as soon as possible.

The device has been delivered to the department’s 1aboatories for testing. If these tests, scheduled for six months’ time, are successful, the makers will bring the product to market within about a year.

【推荐3】For Canaan Elementary’s second grade in Patchogue, N.Y., today is speech day, and right now it’s Chris Palaez’s turn. The 8-year-old is the joker of the class. With shining dark eyes, he seems like the kind of kid who would enjoy public speaking.

But he’s nervous. “I’m here to tell you today why you should … should…” Chris trips on the “-ld,” a pronunciation difficulty for many non-native English speakers. His teacher, Thomas Whaley, is next to him, whispering support. “…Vote for …me …” Except for some stumbles, Chris is doing amazingly well. When he brings his speech to a nice conclusion, Whaley invites the rest of the class to praise him.

A son of immigrants, Chris stared learning English a little over three years ago. Whaley recalls (回想起) how at the beginning of the year, when called upon to read, Chris would excuse himself to go to the bathroom.

Learning English as a second language can be a painful experience. What you need is a great teacher who lets you make mistakes. “It takes a lot for any student,” Whaley explains, “especially for a student who is learning English as their new language, to feel confident enough to say, ‘I don’t know, but I want to know.’”

Whaley got the idea of this second-grade presidential campaign project when he asked the children one day to raise their hands if they thought they could never be a president. The answer broke his heart. Whaley says the project is about more than just learning to read and speak in public. He wants these kids to learn to boast (夸耀) about themselves.

“Boasting about yourself, and your best qualities,” Whaley says, “is very difficult for a child who came into the classroom not feeling confident.”

【推荐2】Grading Policies for Introduction to Literature

Grading Scale

90-100, A; 80-89, B; 70-79, C; 60-69, D; Below 60, E.

Essays (60%)

Your four major essays will combine to form the main part of the grade for this course: Essay 1 = 10%; Essay 2 = 15%; Essay 3 = 15%; Essay 4 = 20%.

Group Assignments (30%)

Students will work in groups to complete four assignments (作业) during the course. All the assignments will be submitted by the assigned date through Blackboard, our online learning and course management system.

Daily Work/In-Class Writings and Tests/Group Work/Homework (10%)

Class activities will vary from day to day, but students must be ready to complete short in-class writings or tests drawn directly from assigned readings or notes from the previous class’ lecture/discussion, so it is important to take careful notes during class. Additionally, from time to time I will assign group work to be completed in class or short assignments to be completed at home, both of which will be graded.

Late Work

An essay not submitted in class on the due date will lose a letter grade for each class period it is late. If it is not turned in by the 4th day after the due date, it will earn a zero. Daily assignments not completed during class will get a zero. Short writings missed as a result of an excused absence will be accepted.

What will happen if you submit an essay one week after the due date?