The deadliest Ebola(埃博拉病毒) outbreak inrecorded history is happening right now. The outbreak is unprecedented(空前的) both in the number of people who have gotten sick and in the geographic scope. And so farit's been a long battle that doesn't appear to be slowing down.

    Ebola is both rare and very deadly. Since the first outbreak in 1976, Ebola viruses have infected thousands of people and killed roughly killed 60 percent of them. Symptoms can come on quickly and kill fast.

    The current outbreak started in Guinea sometime in late 2013 orearly 2014. It has since spread to Sierra Leone and Liberia, including somecapital cities. And one infected patient traveled on a plane to Nigeria, where he spread the disease to several others and then died. Cases have also popped up in various other countries throughout the world, including in Dallas and NewYork City in the United States.

    The Ebola virus has now hit many countries, including Guinea, Liberia, Sierra Leone, Nigeria, Senegal, and the United States. The virus, which starts off with flu-like symptoms and sometimes ends with bleeding, has infected about 6,500 people and killed more than 3,000 since this winter, according to the World Health Organization on September 30, 2014.

    There are some social and political factors contributing to the current disaster. Because this is the first major Ebola outbreak in WestAfrica, many of the region's health workers didn't have experience or trainingin how to protect themselves or care for patients with this disease.

    Journalist David Quammen put it well in a recent New York Timesarticle, “Ebola is more dangerous to humans than perhaps any known virus on Earth, except rabies(狂犬病) and HIV. Andit does its damage much faster than either.”

    Hopefully, researchers are working to find drugs, including a recent $50 million push at the National Institutes of Health. And scientists are working on vaccines(疫苗), including looking into ones that might be able to help wild chimpanzees, which are also susceptible to the disease. The first human Ebola vaccine trial is scheduled to start in the spring of 2015.

Five years ago, when I taught art at a school in Seattle, I used Tinkertoys as a test at the beginning of a term to find out something about my students. I put a small set of Tinkertoys in front of each student, and said: "Make something out of the Tinkertoys. You have 45 minutes today-and 45 minutes each day for the rest of the week."

    A few students hesitated to start. They waited to see what the rest of the class would do. Several others checked the instructions and made something according to one of the model plans provided. Another group built something out of their own imaginations.

    Once I had a boy who worked experimentally with Tinkertoys in his free time. His constructions filled a shelf in the art classroom and a good part of his bedroom at home. I was delighted at the presence of such a student. Here was an exceptionally creative mind at work. His presence meant that I had an unexpected teaching assistant in class whose creativity would infect other students.

Encouraging this kind of thinking has a downside. I ran the risk of losing those students who had a different style of thinking. Without fail one would declare, "But I'm just not creative."

"Do you dream at night when you're asleep?"

"Oh, sure."

"So tell me one of your most interesting dreams." The student would tell something wildly imaginative. Flying in the sky or in a time machine or growing three heads. "That's pretty creative. Who does that for you?"

"Nobody. I do it."

"Really — at night, when you're asleep?"

"Sure."

"Try doing it in the daytime, in class, okay?"

    However wealthy we may be, we can never find enough hours in the day to do everything we want. Economics deals with this problem through the concept of opportunity cost, which simply refers to whether someone's time or money could be better spent on something else.

    Every hour of our time has a value. For every hour we work at one job we could quite easily be doing another, or be sleeping or watching a film. Each of these options has a different opportunity cost—namely, what they cost us in missed opportunities.

    Say you intend to watch a football match but the tickets are expensive and it will take you a couple of hours to get to and from the stadium. Why not, you might reason, watch the game from home and use the leftover money and time to have dinner with friends? This—the alternative use of your cash and time—is the opportunity cost.

    For economists, every decision is made by knowledge of what one must forgo—in terms of money and enjoyment—in order to take it up. By knowing precisely what you are receiving and what you are missing out on, you ought to be able to make better-informed, more reasonable decisions. Consider that most famous economic rule of all: there's no such thing as a free lunch. Even if someone offers to take you out to lunch for free, the time you will spend in the restaurant still costs you something in terms of forgone opportunities.

    Some people find the idea of opportunity cost extremely discouraging: imagine spending your entire life calculating whether your time would be better spent elsewhere doing something more profitable or enjoyable. Yet, in a sense it's human nature to do precisely that—we assess the advantages and disadvantages of decisions all the time.

    In the business world, a popular phrase is “value for money.” People want their cash to go as far as possible. However, another is fast obtaining an advantage: “value for time.” The biggest restriction on our resources is the number of hours we can devote to something, so we look to maximize the return we get on our investment of time. By reading this passage you are giving over a bit of your time which could be spent doing other activities, such as sleeping and eating. In return, however, this passage will help you to think like an economist, closely considering the opportunity cost of each of your decisions.

    Music for Humans and Humpback Whales (座头鲸)

    As researchers conclude in Science, the love of music is not only a universal feature of the human species but is also deeply fixed in complex structures of the human brain and is far more ancient than previously suspected.

    In the articles, researchers present various evidence to show that music-making is at once an original human “business”, and an art form with skillful performers throughout the animal kingdom.

    The new reports stress that humans hold no copyright on sound wisdom, and that a number of nonhuman animals produce what can rightly be called music, rather than random sound. Recent in-depth analyses of the songs sung by humpback whales show that, even when their organ would allow them to do otherwise, the animals converge on the same choices related to sounds and beauty, and accept the same laws of song composition as those preferred by human musicians, and human ears, everywhere.

    For example, male humpback whales, who spend six months of each year doing little else but singing, use rhythms (节奏) similar to those found in human music and musical phrases of similar length—a few seconds. Whales are able to make sounds over a range of at least seven octaves (八度音阶), yet they tend to move on through a song in beautiful musical intervals (间隔), rather than moving forwards madly. They mix the sounds like drums and pure tones in a ratio (比例) which agrees with that heard in much western music. They also use a favorite technique of human singers, the so-called A-B-A form, in which a theme is stated, then developed, and then returned to in slightly revised form.

Perhaps most impressive, humpback songs contain tunes that rhyme. “This suggests that whales use rhyme, the same way we do: as a technique in poem to help them remember complex materials,” the researchers write.

    The best tool needed for survival in the event you get lost when you travel is your skill of advanced planning. You must expect the unexpected and plan accordingly. Even if you are going out for just a few hours, pack enough essentials that you can stay hydrated (体内水分), fueled and prepared for any type of weather. Your essentials should include at least:

    More than enough food and water for the activity you plan.

    A compass that you know how to use. You may want a GPS device, but those sometimes do not receive a signal or the battery fails. Cell phones also likely will not work because of a lack of signal.

    Appropriate maps. Study the terrain (地形) and your planned route. Know where you are going and how you will return.

    Comfortable hiking boots, clothes that you can wear depending on the weather conditions and additional socks in case the ones you arc wearing get wet.

    A blanket, flashlight, matches kept in a water-resistant container, and other items that will help you survive overnight if necessary.

    Cheek with the local forest office for special warnings, such as fires in the area, bear sightings, flooding, trail or road closures, etc.

It's also important that once you have planned your outing, tell someone. Give them exact details of where you are going, the trail you plan to follow, when you will return, the vehicle you are driving (and where you plan to park) and how many people will go with you—do not go alone.

    If you do become lost, your most important tool is keeping a positive mental attitude.

    Last week I did something that scared me. I stood in front of nearly 200 financial planners and I talked to them about why financial blogs are a good thing. I'm a confident writer. I've been doing this long enough that I know my strength and my limitations. I'm less confident as a speaker. I don't have time to pause to collect my thoughts. I'm not able to edit. I'm afraid of being trapped in a corner without being able to talk my way out. Basically, I'm scared to speak.

    It would be easy to simply refuse the chances that come my way. When somebody asks me to speak in front of a group, I could say "no". When radio and television stations call for an interview, I could say "no". But for the past two years, I've been following my own policy to say "yes" to new chances.

    To say "yes" is to live in fear. My goal is to continually improve myself to become better than I am today. One way to do that is to do the things that scare me, to take them on as challenges, and to learn from them—even if I fail.

    In mid-November, a local station asked me to appear on live television. "I realize it's short notice," the producer wrote, "but we'd love to have you on the show if you're available tonight." I was frightened. I thought about recent taped television interviews that I had hated. I was afraid of what might happen.

    But I also thought about the things that had gone right. I thought of how my speaking skills had improved over the past year. And then I thought of the book I was reading, a book that I had bought for $1.29 at the local store. The Magic of Thinking Big was a huge bestseller during the 1960s. Written by Dr. David Schwartz, a professor at Georgia State University, the book contains dozens of practical tips on how to take risks to achieve big goals. Schwartz argues that nobody will believe in you until you believe in yourself.

    So when the television producer asked if I wanted to appear on his show, I thought big. "Sure," I said. "I'll do it." I acted confidently, but on the inside I was frightened. What I needed was techniques to build up my confidence and to overcome my fear.