【正文】 的需求和供應(yīng)，今年是該條約生效五周年。Eighty percent of the signers have banned the sale of tobacco products to young people. Seventy percent have required health warnings on tobacco products.80%的締約國已禁止向青少年出售香煙，還有70%的締約國要求在香煙盒上標(biāo)明健康警示。The . estimates that tobacco use caused one hundred million deaths in the twentieth century. If current rates continue, that number could reach one billion in this century.世衛(wèi)組織估計(jì)，20世紀(jì)吸煙造成了1億人死亡，如果照此繼續(xù)下去，這個(gè)數(shù)字在本世紀(jì)將達(dá)到10億。Events are planned in a number of countries to mark World No Tobacco Day. Many of the events are aimed at persuading people, especially the young, not to start smoking. Others aim to educate people about the many health benefits of quitting.許多國家都在籌備舉行世界無煙日活動(dòng)。這些活動(dòng)多數(shù)旨在勸說人們，尤其是年輕人不要開始吸煙。其他一些則旨在教育人們不吸煙對(duì)健康的益處。Pretty FlowersThis is the VOA Special English Agriculture Report.這里是美國之音慢速英語農(nóng)業(yè)報(bào)道。Not all research begins with a plan. Some studies begin by accident. Meredith Schafer says that is what happened with her and Cynthia Sagers.并非所有的研究都是有計(jì)劃的開始的，一些研究的開始純屬偶然。梅勒迪斯謝弗（Meredith Schafer）說，她和辛西婭薩格斯（Cynthia Sagers）的研究就是如此。Cynthia Sagers is a biology professor at the University of Arkansas. Meredith Schafer is a graduate student.薩格斯是阿肯色大學(xué)的一名生物學(xué)教授。斯謝弗是一名研究生。They were traveling in the state of North Dakota on a project. They noticed pretty yellow flowers.她們?cè)诒边_(dá)科他州進(jìn)行一個(gè)項(xiàng)目時(shí)注意到一些非常漂亮的黃色花朵。They recognized them as canola. Farmers grow canola for seeds to make cooking oil. Canola is also used for animal feed and biofuel.她們認(rèn)為這是卡諾拉。農(nóng)民們種植卡諾拉，用其菜籽煉制食用油?？ㄖZ拉還能用于動(dòng)物飼料和生物燃料。注：Canola，卡諾拉，加拿大雙低油菜。Canola是Can（Canadian，加拿大）o（oil，油）, l（low，低） a（acid，酸）的縮寫。But the canola plants they saw were not growing in farm fields. They were growing along the road.但是他們看到的卡諾拉植株并非長在農(nóng)田里，而是長在路邊。The researchers decided to test the plants. They had brought along special testing papers for the project they were working on. They crushed some of the leaves in water and added the test strips.研究人員決定對(duì)這種植株做個(gè)測(cè)試。他們隨身攜帶了一種用于她們正在進(jìn)行的項(xiàng)目的特殊試紙。她們將一些葉子碾碎后與水混合，然后將試紙放入。The results showed that the weedy canola plants contained genetic changes. If a plant is genetically modified, that means its genes have been changed to produce desired qualities.結(jié)果顯示，這種雜草般的卡諾拉植株存在基因變異。如果一種植物是轉(zhuǎn)基因植物，則意味著它的基因被改造以獲得更好的品質(zhì)。This summer, the researchers from Arkansas went back to North Dakota. This time they went on a road trip to find canola. They traveled more than five thousand kilometers.今年夏天，阿克色州的研究人員再次回到北達(dá)科他州。這一次，他們沿路尋找卡諾拉，行程超過5千公里。They stopped about every eight kilometers to count plants and take samples to test in their vehicle.他們每8公里停下來統(tǒng)計(jì)植株數(shù)目并采樣在車上進(jìn)行測(cè)試。What they found, they say, was the first discovery in the United States of wild canola plants with modified genes.他們稱他們?cè)诿绹状伟l(fā)現(xiàn)基因變異的野生卡諾拉植物。Meredith Schafer presented the findings at a recent meeting of the Ecological Society of America.薩格斯在美國生態(tài)學(xué)會(huì)近期一次會(huì)議上提交了該發(fā)現(xiàn)。The scientists found canola plants in almost half of the places they investigated. They tested a total of two hundred eightyeight plants. They found that eighty percent of those plants contained genes from genetically engineered canola.科學(xué)家們?cè)谒麄冋{(diào)查過的近一半地區(qū)發(fā)現(xiàn)了卡諾拉植株。他們對(duì)其中的288株進(jìn)行了測(cè)試后發(fā)現(xiàn)，80%的植株攜帶轉(zhuǎn)基因卡諾拉的基因。Some crop plants are modified to resist damage from the chemicals that farmers spray to kill weeds. There are two proteins that can give canola the ability to resist two monly used herbicides. One protein gives resistance against glyphosate. The other protein gives resistance against glufosinate.有些農(nóng)作物被基因改造，以抵抗農(nóng)民噴灑的除草劑的損害。有兩種蛋白質(zhì)可以使卡諾拉擁有抵抗2種常用除草劑的能力。其中一種產(chǎn)生草甘膦抗藥性，另一種產(chǎn)生草胺磷抗藥性。Two of the plants growing in the wild showed resistance to both kinds of weed killers. Professor Sagers says canola varieties with these genetic qualities have not been released on the market. This suggests the result of wild populations reproducing on their own.2株野生植株對(duì)兩種除草劑都顯示出抗藥性。薩格斯教授稱，存在這種基因性狀的卡諾拉品種并未在市場(chǎng)上發(fā)布。這意味著，這是野生種群自我繁殖的結(jié)果。PubertyThis is the VOA Special English Health Report.這里是美國之音慢速英語健康報(bào)道節(jié)目。A mother in Washington noticed something unusual one day, just before her daughter39。s eighth birthday.華盛頓市一位母親在女兒8歲生日前的某天注意到一些異常。 MOTHER: I noticed around the end of two thousand eight, I think she39。s getting breasts. This is ridiculous, she39。s seven, and I thought I was crazy. So, when we went for our annual checkup, I asked the doctor if I was right. And she said, 39。Yeah, she has breast buds.39。母親：“2008年底左右，我覺得她的乳房好像開始發(fā)育了。這很荒唐，她才7歲，我想我肯定是瘋了。在我們?nèi)プ瞿甓润w檢時(shí)，我向醫(yī)生進(jìn)行了咨詢。她說，是的，她乳房開始發(fā)育了。Last year a study in Denmark reported an increase in early breast development. Now a new study in the journal Pediatrics adds to evidence of an increase in early puberty in American girls.去年丹麥的一項(xiàng)研究報(bào)告稱，乳房提前發(fā)育的女孩數(shù)量有所增加?，F(xiàn)在兒科雜志的一項(xiàng)新的研究進(jìn)一步證明，發(fā)育提前的美國女孩數(shù)量有所增加。The study took place in three big cities. Dr. Frank Biro at Cincinnati Children39。s Hospital Medical Center in Ohio led the study. He says it began about seven years ago.這項(xiàng)研究在3個(gè)大城市進(jìn)行，俄亥俄州辛辛那提兒童醫(yī)院醫(yī)學(xué)中心的弗蘭克比羅（Frank Biro）醫(yī)生領(lǐng)導(dǎo)了這項(xiàng)研究。他說，這項(xiàng)研究大約開始于7年前。FRANK BIRO: We followed this group of approximately twelve hundred girls on a regular basis to see when they would enter into puberty.比羅：“我們對(duì)大約1200名的一組女孩進(jìn)行定期跟蹤觀察，以確定她們什么時(shí)候開始發(fā)育?！盌r. Biro says the study found that white girls had the greatest increase in rates of breast development. The rates, he says, were about twice as high for seven and eightyearolds pared to earlier studies.比羅醫(yī)生稱，研究發(fā)現(xiàn)，白人女孩乳房提前發(fā)育比例的增幅最大。對(duì)78歲的女孩來說，這個(gè)比例大概是此前研究數(shù)據(jù)的2倍。At age seven, the rates were ten percent of whites, twentythree percent of blacks and fifteen percent of Hispanics.在7歲時(shí)，白人女孩乳房提前發(fā)育的發(fā)生比例是10%，黑人是23%，拉丁裔是15%。Dr. Biro says girls with a higher body mass index are more likely to enter puberty early. Body mass index, or BMI, is a measure of weight in relation to height. But the nation39。s increase in overweight children may be only part of the explanation.比羅醫(yī)生表示，BMI指數(shù)（身體質(zhì)量指數(shù)，簡稱體質(zhì)指數(shù)又稱體重指數(shù)，英文為Body Mass Index，簡稱BMI）越高的女孩提前進(jìn)入發(fā)育期的可能性越大。BMI指數(shù)衡量身高和體重的關(guān)系。美國超重兒童數(shù)量的增加可能只是其中的部分原因。The researchers have been collecting blood and urine sa