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The human voice, like any sound produced by thrumming a stretched string, has a fundamental frequency. For voice, the centre of that frequency lies mostly below 300Hz depending on the speaker"s sex. Information is conveyed through simultaneous higher-frequency overtones(泛音)and additional components that can stretch up to 20,000 Hz(20kHz). Modern hearing aids are able to distinguish only a small part of that range, typically between 300Hz and 6kHz, reducing noise and amplifying those frequencies where the wearer"s hearing is the weakest. But differentiating elements of many common parts of speech occur in higher frequencies. This is the result both of harmonics(和声)that ripple out from the main tone, and from non-voiced elements used to utter consonants(辅音), which employ the tongue, teeth, cheeks and lips. Take the words "sailing" and "failing". Cut off the higher frequencies and the two are indistinguishable. The problem is compounded on telephone calls, which do not transmit frequencies below 300Hz or above 3.3kHz. People with hearing aids experience this problem constantly, says Brian Moore of the University of Cambridge. Typical hearing loss tends to be most acute at frequencies above 10kHz, which contain quieter sounds but where speech can still include important cues. Older hearing aids cut off at no higher than 6kHz, but much modern equipment stretches this range to 8-10kHz. However, a problem remains, Dr Moore says, because bespoke hearing-aid calibrations for individual users, called "fittings" , do not properly boost the gain of these higher frequencies. So Dr Moore and his colleagues have come up with a better method. Their approach can be applied to many existing devices, and is also being built into some newer ones. A key step in any fitting involves testing an individual"s ability to hear sounds in different frequency bands. Each hearing loss is unique, and for most users a standard profile would be too loud in some ranges and too soft in others. But current tests pay scant attention to the higher frequencies that a device"s tiny speaker can produce, regardless of whether the user needs a boost. Dr Moore"s new test, known as CAM2, which is both a set of specifications and an implementation in software, extends and modifies fittings to include frequencies as high as 10kHz. When the results are used to calibrate a modern hearing aid, the result is greater intelligibility(可懂度)of speech compared with existing alternatives. CAM2 also improves the experience of listening to music, which makes greater use of higher frequencies than speech does. Audiphones can help people with hearing problem by______.
A young consultant"s life is tiring. A typical week starts before dawn on Monday, with a rush to the airport and a flight to wherever the client is based. A typical brain-for-hire can expect to stay in hotels at least three nights a week, texting a distant lover. " It"s quite normal to spend a year living out of a suitcase," sighs one London-based consultant. An ex-McKinseyite in New York adds that 15 to 18-hour weekdays are normal and six to eight-hour Saturdays and Sundays common. It can be draining, she admits. So the job appeals to "insecure over-achievers"—a phrase widely used in the industry—"who are always worried that they haven"t done enough work," jokes a former employee of Bain & Company. Some 60—65% of consultants are recent college-leavers. Most drop out within a few years and take more settled jobs elsewhere in the business world, where their experience and contacts allow them to do better than their less-travelled counterparts. The elite consultancies have offices in big cities, which is where ambitious young people want to live. The best-paid jobs are in places like London, New York and Shanghai. Such cities are also where the culture and dating opportunities are richest. "Everything that happens, happens in London," says Una Paulauskaite of the Young Management Consultancies Association, speaking of Britain. Other countries are less unipolar, but all have a divide between the big city and the remote areas. Companies based outside the big cities also need " clever people doing clever stuff" , as one consultant puts it. "But" , he adds, citing a litany of dull suburban towns in which he has managed projects, " there is no way in hell I"d have taken a permanent job in one of those places. " A recent graduate working at a rival firm agrees: " I wouldn"t have considered working for a firm outside London. " Such attitudes are frustrating for firms in Portsmouth or Peoria. But consultancies benefit from remote areas. They recruit bright young things in the metropolis and then hire out their brains to firms in the sticks. This is one reason why consultants have to travel so much. The system works, more or less, for everyone. Firms in the provinces get to borrow talent they could not easily hire. And young consultants get to experience life in the real world before returning to the capital to party with their friends at the weekend. They have it all; except enough sleep. The best title of the passage could be______.
The human voice, like any sound produced by thrumming a stretched string, has a fundamental frequency. For voice, the centre of that frequency lies mostly below 300Hz depending on the speaker"s sex. Information is conveyed through simultaneous higher-frequency overtones(泛音)and additional components that can stretch up to 20,000 Hz(20kHz). Modern hearing aids are able to distinguish only a small part of that range, typically between 300Hz and 6kHz, reducing noise and amplifying those frequencies where the wearer"s hearing is the weakest. But differentiating elements of many common parts of speech occur in higher frequencies. This is the result both of harmonics(和声)that ripple out from the main tone, and from non-voiced elements used to utter consonants(辅音), which employ the tongue, teeth, cheeks and lips. Take the words "sailing" and "failing". Cut off the higher frequencies and the two are indistinguishable. The problem is compounded on telephone calls, which do not transmit frequencies below 300Hz or above 3.3kHz. People with hearing aids experience this problem constantly, says Brian Moore of the University of Cambridge. Typical hearing loss tends to be most acute at frequencies above 10kHz, which contain quieter sounds but where speech can still include important cues. Older hearing aids cut off at no higher than 6kHz, but much modern equipment stretches this range to 8-10kHz. However, a problem remains, Dr Moore says, because bespoke hearing-aid calibrations for individual users, called "fittings" , do not properly boost the gain of these higher frequencies. So Dr Moore and his colleagues have come up with a better method. Their approach can be applied to many existing devices, and is also being built into some newer ones. A key step in any fitting involves testing an individual"s ability to hear sounds in different frequency bands. Each hearing loss is unique, and for most users a standard profile would be too loud in some ranges and too soft in others. But current tests pay scant attention to the higher frequencies that a device"s tiny speaker can produce, regardless of whether the user needs a boost. Dr Moore"s new test, known as CAM2, which is both a set of specifications and an implementation in software, extends and modifies fittings to include frequencies as high as 10kHz. When the results are used to calibrate a modern hearing aid, the result is greater intelligibility(可懂度)of speech compared with existing alternatives. CAM2 also improves the experience of listening to music, which makes greater use of higher frequencies than speech does. We can infer from Paragraph 3 that______.
关于细菌芽孢的叙述，下列哪项是错误的
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