Writing1.
Directions: In this part there is an essay in Chinese. Read it carefully and then write a summary of 200 words in English on the ANSWER SHEET. Make sure that your summary covers the major points of the passage. 全球气候变化与传染病
气候是传染病传播的重要影响因素之一,气象学家们预测到2100年,全球平均气温将上升20℃。气候变化将可能干扰地区的天气形式和生态平衡,从而造成对人体健康的多方面影响。在由气候变化产生的健康效应中,其中最重要的一个方面就是对传染病传播的影响。全球气候变化将直接或间接影响许多传染病(尤其是虫媒传染病譬如疟疾、血吸虫病、病毒性脑炎和登革热等)的传播过程。全球变暖还将使海平面和海表面温度上升,从而增加经水传播的疾病(例如霍乱和贝类水产品中毒)的发病率。
1.气候变化对虫媒传染病的影响
全球气候变化将影响虫媒传染病的传播,这些影响主要表现在改变虫媒的地区分布,增加虫媒繁殖速度与侵袭力和缩短病原体的外潜伏期。受气候变化影响较大的虫媒传染病包括疟疾、血吸虫病、登革热和其它虫媒病毒性疾病。
疟疾疟疾是全球流行最严重的虫媒传染病。气候因素(如温度和湿度)直接影响疟疾的传播,由于疟原虫一般在16℃以下难以存活,所以疟疾分布有地区性。温度可直接影响疟原虫的生长和蚊虫的生命周期。充沛的雨量有利于蚊虫的滋生,适宜的气候条件可加强蚊虫的侵袭力。计算机模型预测到2100年,世界人口受疟疾影响的比例将可能由现在的45%增至60%,即每年将新增病例5000万~8000万。
血吸虫病现场和实验资料表明,气温可影响血吸虫和钉螺的生长发育、繁殖和死亡,并可影响人群和疫水的接触情况。一般在低气温时(9℃以下),血吸虫感染不会发生,但感染机率随气温升高而增加,气温在24℃~27℃时,血吸虫感染率可达最高。但气温过高时(39℃或以上),可造成钉螺死亡,血吸虫感染率反而下降。此外,钉螺分布还受到降雨量的影响。最近据数学模型预测,到2050年,由气候变化而增加的血吸虫病例数可高达500万。
登革热和其它虫媒传染病全世界有五百多种虫媒病毒,其中一百多种可引起人类疾病,在适当情况下,虫媒病毒可引起相关疾病的爆发流行。受气候变化影响较大的虫媒病毒病包括登革热、病毒性脑炎和黄热病。
其它的一些虫媒传染病,譬如淋巴丝虫病和河盲病也可能受到气候变化的影响。
2.气候变化对水传播疾病的影响
气候变化(诸如气温升高,降雨量增加,更频繁的洪水,风暴和海平面上升等)和环境恶化(如在难民营里)可引起霍乱爆发流行。最近,霍乱流行的生态学观点越来越受到科学界的重视,即自然生态系统的失衡与霍乱大流行有关。现已知海洋浮游植物为霍乱(或副霍乱)弧菌提供了栖息场所。当海水温度上升或呈富营养化时(如沿海城市向海洋排污过多),海洋浮游植物大量繁殖(如海藻泛滥造成“赤潮”)。这将有利于霍乱和其它疾病(如贝类海产品中毒)的爆发流行。
3.气候变化对其他传染病的影响
污染的食物能传播疾病,食物在其制作、储藏、运输和销售过程中均可能被污染。气候变化对以上污染过程可能造成影响,因此,全球趋暖将可能增加经食物传播疾病的发生。此外,其他一些传染病(如肾综合征出血热和钩虫病)的传播也可能受到气候变化的影响。
结论
传染病的模式和传播过程受到多因素的影响。不同传染病对气候变化的敏感程度是不一样的,为做好传染病的控制和预防工作,准确预测传染病的传播趋势极其重要。这需要建立新的,多学科合作的分析方法和积极发展传染病防治战略。加强流行病学监测有益于研究传染病的传播趋势,也有助于发展控制和预防疾病传播的公共卫生措施。全球气候变化,与其他正在改变的社会环境因素一起,已对传染病研究工作者提出新的挑战。
[范文]Global Climate Change and Infectious Diseases
Climate is one of the most important factors that have an effect on the spread of infectious diseases. Global climate changes will directly and indirectly influence the transmission of many infectious diseases.
Firstly, climate changes will alter the geographic distribution of arthropod, accelerate its reproduction and shorten the extrinsic incubation period of its pathogen, thus affecting the spread of arthropod-borne infectious diseases,such as malaria, snail fever and dengue etc.
Secondly, climate changes may cause a widespread of cholera. Marine phytoplankton can provide habitat for Vibrio cholera. Therefore when marine temperature increases or eutrophicaiton occurs, the chance of a cholera epidemic is extremely high.
Thirdly, global warming increases the likelihood of food-borne infection because it may work on the contamination of food when the food is made, stored, transported or sold. Besides, some other diseases may also spread differently due to climate changes.
To conclude, global climate changes possess a new challenge to researchers of infectious diseases. It is a pressing task to strengthen the monitoring of infectious diseases, which is helpful for the research and the prevention of such diseases.
2.
Directions: Nowadays we can see American films and TV programs pouring in, fast food restaurants popping up in our cities, and many other imported products dominating our markets. Many people are happy to see them whereas others worry about such trends. Give your opinion in an essay of no less than 250 words.
[范文]
Nowadays people are increasingly aware that more and more exotic products appear in Chinese market. We can see a lot of Korean and Japanese games pour in, American films occupy our theaters, Mcdonald's pop up in our cities and other imported products dominate our markets.
Some people believe this phenomenon is good whereas others worry about such trends. As far as I am concerned, just like a two-edged sword, both advantages and disadvantages are going with this phenomenon. Above all, some imported products are of high quality and at reasonable prices, which is surely beneficial to Chinese consumers. Besides relishing a lot more consumer goods than ever before, Chinese people could have a great many choices of selecting products. Secondly, domestic entrepreneurs .who confront the competition of foreign products have to research and develop new products, to improve their services and to reform illogical management systems. So we can say that such trends will bring benefits to both Chinese consumers and manufacturers in a certain degree.
Yet not everything will always go smoothly. The negative effect of foreign products exists in many aspects. As we all know, China that is still a developing country needs to advance her own national industries, Only in this way, can the whole process of reform and opening-up be pushed forward. However, China's native entrepreneurs are confronting great threat from foreign companies, especially US corporations. Chinese market room is limited. If domestic entrepreneurs want to conquer it, they must possess advanced and core technology and sufficient fund of R&D, improving design, advertisement and promotion. If not, it is extremely hard for Chinese companies to survive in the competitive market.
Altogether, it is improper to judge that such trends are completely good or bad. However, there is one point that we have to admit, these two types of effects are in- evitable. As 10ng as Chinese entrepreneurs act initiatively to learn from and compete with foreign companies, they will overcome all the difficulties.
3.
Directions: Please read the following article in Chinese carefully, and then write a summary of 200 words in English on the ANSWER SHEET. Make sure that you cover all the major points of the article.
科学家说,在第一批艾滋病例被发现以后的20年里,他们对这种病毒性疾病的了解已超过其他任何一种病毒性疾病。但是,联合国艾滋病规划署的负责人彼得·皮奥和国际艾滋病学会会长罗马的斯特凡诺·韦拉及其他一些专家都认为,全面考察那些尚未解决的问题,可能对艾滋病和其他疾病治疗的进展是一项有益的举措。
这些较广泛的重要科学问题包括:
为什么艾滋病使患者容易感染某些癌症和传染病?
一种传统的说法是,癌细胞在人体内不断繁殖,但受到健康免疫系统的控制。艾滋病的情况却不是这样。艾滋病人很容易患非何杰金氏淋巴瘤和卡波西氏肉瘤,但不易患美国最常见的乳腺癌、结肠癌和肺癌等。这说明,受损的免疫系统(至少是艾滋病患者的免疫系统)可以抑制普通癌细胞的发展。
艾滋病病毒侵入人体后通过什么途径摧毁免疫系统?
当艾滋病病毒通过性接触传播时,病毒必须穿过组织屏障进入人体。这个过程目前尚不清楚。病毒可能直接侵入,或许由一系列不同种类的细胞带入。最终,艾滋病病毒穿过淋巴管到淋巴结和淋巴系统的其他部分。但病毒是如何摧毁人体内负责打击入侵传染体的CD-4细胞的,目前还无法确定。
艾滋病病毒是怎样破坏免疫系统的?
艾滋病病毒能杀死对付自己的免疫细胞,但艾滋病病毒携带者患艾滋病的快陧却大不相同。因此科学家提出问题:免疫系统中那些使人患艾滋病时间出现差异的因素能否被识别出来?如果能,它们能否用于制止艾滋病患者病情的恶化,甚至在最初就可能防止人们感染艾滋病病毒?
最有效的艾滋病疗法是什么?
从理论上来说,尽早治疗可以提供维护免疫功能的最佳时机。但是新药物无法彻底清除体内的艾滋病病毒,因此患者不得不终身服用这些具有危险副作用的药物,而且还可能在产生抗药性时改服别的药物。因此新的方法可能建议在免疫系统出现衰退迹象时才开始治疗。
可能研制出疫苗吗?
毫无疑问,一种有效的疫苗是控制这种瘟疫的关键。但是目前只有一种疫苗进入了全面检验的阶段,而对其会有多大的保护功能,却有着很大的争议。世界各地流行的艾滋病在遗传类型上各不相同,目前还不清楚的是,从某种艾滋病病毒获得的疫苗能否防止其他类型的艾滋病。
如果没有疫苗,能否阻止艾滋病病毒的传播?
如果没有深入集中的行为研究,仅靠宣传是无法阻止这种全球性瘟疫的。
注意:写作部分要求50分钟内完成。
[范文]
In the 20 years since the first cases of AIDS were detected, scientists say they have learned more about this disease.
Yet Peter Piot, who directs the United Nations AIDS program, and Stefano Vella of Rome, president of the International AIDS Society, and other experts say reviewing unanswered questions could prove useful as a measure of progress for AIDS and other diseases.
Among the important broader scientific questions are:
1.Why does AIDS predispose infected persons to certain types of cancer and infections?
2.What route does HIV take after it enters the body to destroy the immune system?
3.How does HIV subvert the immune system?
4.What is the most effective anti-HIV therapy?
5.Is a vaccine possible?
6.In the absence of a vaccine, how can HW be stopped?
Without more incisive and focused behavioral research, prevention messages alone will not stop the global epidemic.
4.
Directions: Write an essay of no less than 200 words on the topic given below. Use the proper pace on your ANSWER SHEET. Topic:
As a young scientist, which life would you prefer to live: common or uncommon? Why?
[范文] Which Life Would I Prefer to Live as a Young Scientist?
It is a controversial issue whether a young scientist should live a common or an uncommon life. Different people have different opinions. As for me, I prefer to live a common life. I hope my life is as ordinary as most people's around me.
In my daily life, I enjoy spending my leisure time with my family. My parents encourage and support me whenever I encounter difficulties. Although I don't stay with my parents at present, they would call me or write to me whenever I feel depressed. After talking to them, I would regain my confidence to confront any difficulties. In addition, if I score any achievement in my research, my parents are the first people I would like to share it with.
Recreational activities play an important role in people's daily life. As a young scientist, I am so busy with my research that I need more entertainment than others. Like most people, I am keen on listening to music, seeing a film, practicing Karaoke during my spare time. From these activities, I not only have a lot of fun and relaxation but also make myself full of energy again with my work.
As we all know, well-known scientist Newton found the law of gravity when he was sitting under a tree. This is also an important reason that I prefer to live a common life rather than an uncommon life. Some scenes that give me inspiration and avail to my re- search exist in ordinary life.
Although my research occupies most of my time, I still enjoy my common life that is the source of my energy as well.
5.
Directions: There are many reasons for a person planning to do PhD research (for example, new experiences, career preparation, and increased knowledge). Why do you think people should pursue a doctoral degree? Write an essay of no less than 200 words about your opinion on this topic. Write your essay on ANSWER SHEET2.
[范文]
Why we pursue doctoral program? It's quite necessary for us to think over the following issues before we want to pursue doctoral program.
First, do you want to do research? That means you'd consider the long-term goals for yourself. To study PhD program is to practice your scientific research capability.
Besides, do you want to work in higher-education schools and institutions? A PhD degree is the prerequisite while you want to get a position in a university.
Furthermore, do you have the adequate capability to study PhD? You'd make an assessment about yourself in terms of the undermentioned aspects.
Last but not least, do bear in mind: on with a PhD hat cannot presume you to have a better job in the future. No other than you affirm that to pursue doctoral program is to enjoy study, to exceed former researchers, you would spend happily this period of your study life.
With regard to myself, my overall study objective is to use the PhD as a vehicle to become a world-class specialist in tourism. I have got to study hard, to enlarge my scope of knowledge, to realize my potentials and to pay for my life. But most importantly, I want to be an optimistic and happy person, to enjoy research.