[A] I’m very well, thank you.[B] Would you like to have another apple[C] Can you help me[D] Wait for a moment, please.[E] It’s very nice of you to help me.[F] May I have your name, please[G] Take the second crossing on the right. It’s very kind of you to help me.
Passage Two Antiseptics(杀菌剂) have saved countless lives, but they are most effective when the bacteria they are attacking are individual cells in suspension. Once bacteria have attached themselves to solid surfaces and formed films, they are far harder to eradicate with standard disinfectants. Bacterial pollution of medical devices is a particular problem, as those devices are then used on people whose immune systems may be in less than best condition. Surgical instruments may be treated with ultraviolet light, but that is not appropriate for everything. The result is that infections arising from bacteria attached to surfaces in clinics and hospitals are reckoned to cause up to 1.4m deaths per year. In order to develop a better method of disinfection, a team led by David Whitten of the University of New Mexico and Kirk Schanze of the University of Florida set out to design the equivalent of a mousetrap for bacteria. The device they came up with is an empty capsule five microns across. It is made of alternating layers of two polymers’(聚合体) ,one of which is positively charged, and the other negatively so. These opposite charges serve to hold the capsule together. The polymers in question also absorb light in a way that is likely to transfer the absorbed energy to nearby oxygen molecules (氧分子) to create what is known as singlet oxygen, a particularly reactive form of the element that would kill any bacteria inside the capsule. To test this idea, the two researchers ran a series of experiments in which they exposed their newly built microcapsules to Pseudomonas aeruginosa, a fatal bacterium commonly, found in hospitals, and also to Cobetia marina, a bacterium that frequently adheres to ships and marine equipment, causing dirt. They found that in both cases the microcapsules attracted and captured bacteria that were nearby. After one hour of exposure to light, they report in a forthcoming issue of Applied Materials & Interfaces, the capsules killed more than 95% of the bacteria used in the study. What kills the bacteria is clear: it is the singlet oxygen. What is attracting them into the microcapsules, though, is not well understood. The researchers infer that the positive electric charge may have the function of attracting bacteria, since many bacteria are negatively charged and would thus be attracted to the polymer in question. Alternatively, because both bacteria and polymers are repelled by water they may be pushed together by this joint repulsion. However it works, the result is what Dr. Whitten describes as a micro-sized Roach Motel ("Bacteria check in, but they don’t check out"). If the idea can be scaled up, it may prove a useful weapon in the fight against hospital-caused infection and marine-dirt alike. It can be inferred from the last paragraph that ______.
A. researchers are quite clear about what attracts bacteria into microcapsules
B. the negative-charged layer of polymers attracted the positive charged bacteria
C. a larger "mousetrap" may be helpful in fighting against infection
D. polymers and bacteria may be pushed together by water’s attraction
[A] I’m very well, thank you.[B] Would you like to have another apple[C] Can you help me[D] Wait for a moment, please.[E] It’s very nice of you to help me.[F] May I have your name, please[G] Take the second crossing on the right. Turn right at the second crossing.
加利福尼亚的消费者在寻求个人贷款时可借助的银行比美国其他州少,银行间竞争的缺乏解释了为什么加利福尼亚的个人贷款利率高于美国其他地区。 下面哪项,如果正确,最显著地削弱了以上的结论
A. 因为要支付相对高的工资来吸引胜任的员工,所以,加利福尼亚的银行为他们提供的许多服务向储户收取的费用比其他地方银行高。
B. 个人贷款比银行做的其他种类贷款如住房按揭贷款风险大。
C. 因为加利福尼亚的银行存款和美国其他地区银行存款都受相同的保险保障,它们的安全性并不比其他地区的银行存款差。
D. 加利福尼亚的消费者不能归还私人贷款的比率比美国其他地区低。
E. 加利福尼亚的银行向储户支付的利率比美国其他地区的银行低,因此在加利福尼亚,吸收储户竞争较少。