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Evolutionary theories. The Belgian George Lemaitre proposed the idea that about 20000 million years ago all the matter in the universe—enough, he estimated, to make up a hundred thousand million galaxies—was all concentrated in one small mass, which he called the "primeval atom". This primeval atom exploded for some reasons, sending its matter out in all directions, and as the expansion slowed down, a steady state resulted, at which time the galaxies formed. Something then upset the balance and the universe started expanding again, and this is the state in which the universe is now. There are variations on this theory: it may be that there was no steady state. However, basically, evolutionary theories take it that the universe was formed in one place at one point in time and has been expanding ever since.Will the universe continue to expand It may be that the universe will continue to expand for ever, but some astronomers believe that the expansion will slow down and finally stop. Thereafter the universe will start to contract until all the matter in it is once again concentrated at one point. Possibly the universe may oscillate for ever in this fashion, expanding to its maximum and then contracting over again.The steady-state theory. Developed at Cambridge by Hoyle, Gold and Bodi, the steady-state theory maintains that the universe as a whole has always looked the same and always will. As the galaxies expand away from each other, new material is formed in some ways between the galaxies and makes up new galaxies to take place of those which have receded. Thus the general distribution of galaxies remains the same. How matter could be formed in this way is hard to see, but no harder than seeing why it should all form in one place at one time.How can we decide which of these theories is closer to the truth The method is in principle quite simple. Since the very distant galaxies are thousands of millions of light years away, then we are seeing them as they were thousands of millions of years ago. If the evolutionary theory is correct, the galaxies were closer together in the past than they are now, and so distant galaxies ought to appear to be closer together than nearer ones. According to the steady-state theory there should be no difference.The evidence seems to suggest that there is a difference, that the galaxies were closer together than they are now, and so the evolutionary theory is partially confirmed and the steady-state theory—in its original form at least—must be rejected. What is the basic difference between the two classes of theories().
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M: When my brother Dan was diagnosed with brain cancer in 2001 and was told he likely had less than a year to live, my family was in complete shock. We immediately started asking questions, many of which went unanswered because there was either no relevant information available (including what causes brain cancer) or conflicting information (including how to treat it). In the middle of our horrific family crisis, we didn’t know who to believe or what we could do. It was this firsthand experience, along with the everyday health issues that all families face, that made me realize that even though the US has some of the best doctors in the world, our nation’s health care system is broken and desperately needs to be fixed. Indeed, even calling it "health care" is somewhat misleading. Given that an estimated 98% of spending goes toward treating illness and only about 2% toward prevention and wellness, it would be more accurate to refer to it as the "sick care" system.From my own personal experience, I’ve discovered that the complex maze of paperwork, uncertainty and confusion that marks today’s health care system are merely symptoms of a much larger illness that affects millions of consumers. The fundamental issue is that, at least in America, the nation’s current health care model does not engage consumers to better manage their own health.One way to cure this is people to make efforts to stay healthy. In the "staying healthy" industry, consumers today spend billions of dollars a year on gym memberships, fitness gear, fruits and vegetables, massages, acupuncture and personal trainers. This broad and diverse industry allows consumers to pick and choose from a variety of providers who are competing for their business. These businesses have to offer clear transparency, competitive prices and superior quality.But something happens when you get a cold, or worse, and are plunged into the black hole of co-payments, insurance claims, preset doctor lists, HMOs, PPOs--and utter dysfunction.The problem is that when most consumers get sick, employers and insurance companies usually pick up the tab. Meanwhile, the consumer is caught in the middle while these two competing forces try to minimize their expenditures. Most of the time, consumers have no idea how much their procedures cost, nor do they care--they’re focused more on their own modest co-pay.Though the challenges of the health care system seem daunting, I see two key trends that will cause major changes to the industry.The first is the shifting financial burden for health coverage to employees. Consumers are now paying more for their health coverage, which means they are demanding more in return. It’s simple economics that if people are paying extra, they will want a bigger role in the decisions about their health care.The second trend is the increasing number of consumers who are concerned about living healthier lives. This is proved by their increased spending in the "staying healthy" industry. Not only are they buying, but consumers are also looking for more information about how to improve their health, fitness and wellness.These trends and my own personal experiences with the health care industry motivated me to create Revolution Health with the hope that we could help produce a shift to a new system driven by consumers, shaped by market forces and powered by technology.Some say health care will never change because consumers tend to be passive about their health. But I truly believe people will be more responsible for improving their health--they just need to be empowered and given tools to make better choices. The diagnosis of the brother’s cancer caught the family off guard.
They cannot stay organized. They finish their homework but then lose it. And they often have trouble focusing in class. In schools across the U. S. young boys are falling behind, while young girls are thriving. Once again, learning differences between the sexes have become a big issue for educators in American schools.In classrooms across the U. S. , there is a new trend that worries educators. In every category and demographic group, boys are falling behind in school.Anita Doyle is a learning specialist who works with kids who are having academic troubles at the private Episcopal High School outside Washington D. C."In this year’s freshman class, I met about five girls and about 30 boys but I have continued to meet with the boys and I don’t see any of the girls. All of the girls have kind of figured out how to do things and they are on their own. Between myself and another learning specialist we meet with about 20 other boys," she says.Episcopal is an elite private high school that admits students based on standardized test scores and grades. Students are generally of similar academic ability.Yet Anita Doyle still sees dramatic differences In performance between the sexes. "A 14-year-old girl is academically more mature than a 14-year-old boy. This makes a huge difference, especially in the high school years. Because, what you are asking of high schoolers is to keep track of five or six subjects, plan ahead for their long term projects, decide what is important to study, to review for tests, and to prioritize, And many boys are not ready to do that task."Recent scientific research suggests that many of these differences may be hard-wired in the brain. Boys mature a year or more later than girls, and are twice as likely to have a learning disability. They tend to fidget and lose focus easily. Brain studies suggest they process language and emotions less efficiently than girls. Boys in the U. S. bring home 70 percent of poor or failing grades and receive the bulk of school suspensions.Twenty years ago, it was the girls who had fallen behind, and efforts to improve their academic performance included hiring more female teachers, who were sensitive to girls’ needs.That has had an impact on boys, says Alvaro Devicente, the Headmaster of The Heights School, a private all-boys school in the Washington area. "I think that in many eases boys are falling behind because there hag been a process over the last 20 years, a process of education becoming more feminine," he said. "And I mean that in sort of a realistic factual sense. Because if you look at the statistics there is a majority of women teachers and a majority of girls in the school that everything gets tailored to the girls and the young women."Armed with the latest statistics, many parents are abandoning the idea of gender equality in schools, acknowledging the differences between the sexes, and turning to same-sex education. The faculty of The Heights School is all male and caters to what Devicente says are the special learning needs of young boys."There have been studies, very interesting studies about how boys hear differently than girls," Devicente notes. "For a boy to really hear the tone, the volume has to ha louder. So if the teacher is speaking at a volume that is comfortable for girls, the boy is going to get distracted because it is like elevator music almost. You start looking around and you are surely going to find a distraction if you are a 12-year-old in a classroom."At the Heights school, boys are given four breaks a day. They are allowed to play tackle football, throw snowballs and vent all of their pent-up energy. Mr. Devieente says that improves their concentration in class."I think that one thing that may happen in other schools is that the way that they try to control boys is by thwarting their passion," he says. "Keeping a lid on them and getting them to do the right thing. And that is very dangerous because you can’t ask a boy to fake it. You have to redirect his passion, and they are going to be passionate and they should be passionate."Ms. Doyle, says it is not a character flaw. "You have got to understand that the way boys behave is not a character flaw. It is who they are," she says. "So you have to start with that premise. You have to start at a situation where they can see what they are capable of."Most educators agree that a wholesale change of teaching practices in schools runs the risk of doing more harm than good. But many believe accepting that differences do exist between the sexes is a starting point for realizing the full potential of every student. What has become a big issue for educators in American schools between the sexes
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When a consumer finds that an item she or he bought is faulty or in some other way does not meet the standard of the manufacturer’s claim for it, the first step is to present the warranty, or any other records which might help, at the store of purchase. In most cases, this action will produce results. However, if it does not, there are various means the consumers may use to gain satisfaction.A simple and common method used by many consumers is to complain directly to the store manager. In general, the "higher up" the consumer takes his or her complaint, the faster he or she can expect it to be settled. In such a case, it is usually settled in the consumer’s favor, assuming he or she has a just claim.Consumers should complain in person whenever possible, but if they can not get to the place of purchase, it is acceptable to phone or write the complaint in a letter.Complaining is usually most effective when it is done politely but firmly, and especially when the consumer can demonstrate what is wrong with the item in question. If this cannot be done, the consumer will succeed best by presenting specific information as to what is wrong, rather than by making general statements. For example, "The left speaker does not work at all and the sound coming out of the right one is unclear" is better than "this stereo does not work".The store manager may advise the consumer to write to the manufacturer. If so, the consumer should do this, stating the complaint as politely and as firmly as possible. But if a polite complaint does not achieve the desired result, the consumer can go a step further. She or he can threaten to take the seller to court or report the seller to a private or public organization responsible for protecting consumers’ rights. What does the talk tell us().
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