In an uncritical August 11, 1997, World News Tonight report on "diamagnetic therapy," a physical therapist explained that "magnets are another form. of electric energy that we now think has a powerful effect on bodies." A fellow selling $ 89 magnets proclaimed: "All humans are magnetic. Every cell has a positive and negative side of it."
On the positive side, these magnets are so weak that they cause no harm. On the negative side, these magnets do have the remarkable power of attracting the pocketbooks of gullible Americans to the tune of about $ 300 million a year. They range in scale from coin- sized patches to mattresses, and their curative powers are said to be nearly limitless, based on the premise that magnetic fields increase blood circulation and enrich oxygen supplies because of the iron pressure in the blood.
This is fantastic flapdoodle and a financial flimflam. Iron atoms in a magnet are crammed together in a solid state about one atom apart from one another. In your blood only four iron atoms are allocated to each hemoglobin molecule, and they are separated by distances too great to form. a magnet. This is easily rested by picking your finger and placing a drop of your blood next to a magnet.
What about claims that magnets attenuate pain? In a 1997 Baylor College of Medicine double-blind study of 50 patients (in which 29 got real magnets and 21 got sham ones), 76 percent in the experimental group but just 19 percent in the control group reported a reduction in pain. Unfortunately, this study included only one 45-minute treatment, did not try other pain-reduction modalities, did not record the length of the pain reduction and has never been replicated.
Scientists studying magnetic therapy would do well to read the 1784 "Report of the Commissioners Charged by the King to Examine Animal Magnetism" (reprinted in an English translation in Skeptic, Vol. 4, No. 3). The report was instituted by French King Louis XVI and conducted by Benjamin Franklin and Antoine Lavoisier to experimentally test the claims of German physician Franz Anton Mesmer, discoverer of "animal magnetism." Mesmer reasoned that just as an invisible force of magnetism draws iron shavings to a lodestone, so does an invisible force of animal magnetism flow through living beings.
What does the passage mainly talk about?
A. It has been proved that magnets do have certain effect on living beings.
B. How iron atoms in a magnet are crammed together.
C. Scientists carried out experiments to test the existence of magnets.
D. It is very easy to test the existence of magnets
Edgar Snow was a reporter and a joumalist. He was a doer, a seeker of facts. His mature years were spent in communicating to people-he was an opener of minds, a bright pair of eyes on what went on about him. Fortunately, he went to many places, knew many people, saw many things; thus he communicated from depth and involvement. Suspicious of dogma, he stated in his autobiography. "What interested me was chiefly people, all kinds of people, and what they thought and said and how they lived-rather than officials, and what they said in their interviews and handouts about whatthey people' thought and saiD." In writing about people and the event which shaped or misshaped their lives, his point of view was essentially honest and searching- founded on his own inquiry and resting on a body of truth perceived with vision and with compassion. His valued friend and editor, Mary Heathcote, stated that to Edgar Snow, "true professionalism meant telling the truth as one saw it, with as many of the reasons for its existence as one could find out and as much empathy as possible for the people experiencing it..."
That he is remembered mostly through Red Star Over China is understandable. The accounts in that book were of international importance and the experience for the author in getting those accounts was perhaps the most significant one in his life. Though it is typical of him what, after the acclaim the book received, he commented, "I simply wrote down that I was told by the extraordinary young men and women with whom it was my privilege to live at age thirty, and from whom I learned a great deal. " That "great deal" spread from the pages of Red Star to alter the thinking of countless people—including many citizens of China who were led by it to action that drastically affected their own lives and the course of their country's future. An awesome realization of personal responsibility also came about at this point for the young journalist, one he was cognizant of the rest of his life—the discovery, as he heard of friends and students killed in a war they had been moved to join largely because of his reports, that his writing had taken on the nature of political action and that he, as a writer, had to be personally answerable for all he wrote.
There were other texts which broke through ignorance and prejudice in similar ways: Far Eastern Front, Living China, Battle for Asia, People on Our Side, Journey To the Beginning, to name some of the eleven books he produced, as well as many pages of engaged reporting—of floods and famines, of wars declared and undeclared, of human dilemmas and indignities, of unsung heroes and unheralded sacrifices-a life's study of the impact of people and events from many lands known at first hanD.
Ed represents what is best in American joumalism—as did his compatriot Agnes Smedley and Jack Belden. They dedicated to action, to communication that would help lessen the need, help correct the injustices. A main objective of theirs, because they were there and they saw, because they were internationalists with concern for human welfare, values and dignity, was to contribute to an understanding of China and the crippling burdens she bore—in a world dominated by arrogance, greed, and ignorance.
According to the article, the writings of Edgar Snow were based on______.
A. facts of life
B. his own peep-hole view
C. the officials'taste
D. his prejudiced imagination
Non-indigenous (non-native) species of plants and animals arrive by way of two general types of pathways. First, species having origins outside the United States may enter the country and become established either as free-living populations or under human cultivation-for example, in agriculture, horticulture, aquaculture, or as pets. Some cultivated species subsequently escape or are released and also become established as free-living populations. Second, species of either US or foreign origin and already within the United States may spread to new locales. Pathways of both types include intentional as well as unintentional species transfers. Rates of species movement driven by human transformations of natural environments as well as by human mobility-through commerce, tourism, and travel-greatly exceed natural rates by comparison. While geographic distributions of species naturally expand or contract over historical time intervals (tens to hundreds of years), species-ranges rarely expand thousands of miles or across physical barriers such as oceans or mountains.
Habitat modification can create conditions favorable to the establishment of non-indigenous species. Soil disturbed in construction and agriculture is open for colonization by non-indigenous weeds, which in turn may provide habitats for the non-indigenous insects that evolved with them. Human-generated changes in fire frequency, grazing intensity, as well as soil stability and nutrient levels similarly facilitate the spread and establishment of non-indigenous plants. When human changes to natural environments span large geographical areas, they effectively create passages for species movement between previously isolated locales. The rapid spread of the Russian wheat aphid to fifteen states in just two years following its 1986 arrival has been attributed in part to the prevalence of alternative host plants that are available when wheat is not. Many of these are non- indigenous grasses recommended for planting on the forty million or more acres enrolled in the US Department of Agriculture Conservation Reserve Program.
A number of factors perplex quantitative evaluation of the relative importance of various entry pathways. Time lags often occur between establishment of non-indigenous species and their detection, and tracing the pathway for a long-established species is difficult. Experts estimate that non-indigenous weeds are usually detected only after having been in the country for thirty years or having spread to at least ten thousand acres. In addition, federal port inspection, although a major source of information on non-indigenous species pathways, especially for agriculture pests, provides data only when such species enter via closely-examined routes. Finally, some comparisons between pathways defy quantitative analysis-for example, which is more "important": the entry path of one very harmful species or one by which many but less harmful species enter the country?
Which of the following statements about species movement is best supported by the passage?
A. Human factors affect species movement rates more than its long-term amount.
B. Natural expansions of species account for their slow natural contractions.
C. Natural environments created by human activities contribute much to species movement.
D. Long-range movement of species depends on the geographic extent of human mobility.
The phrase "that injury" underlined in Paragraphs refers to ______.
A. his bad back
B. the doctor's weightlifting
C. his clinically inappropriate practice
D. his dishonest cheating