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文章大意:这是一篇议论文。文章主要谈论了儿童保育的职业化推高了它的价格。

1 . Gone are the days when a mother’s place was in the home: in Britain women with children are now as likely to be in paid work as their unburdened sisters. Many put their little darlings in day care long before they start school. Mindful that a poor start can spoil a person’s chances of success later in life, the state has intervened ever more closely in how babies and toddlers are looked after. Inspectors call not only at nurseries but also at homes where youngsters are minded; three-year-olds follow the national curriculum. Child care has increasingly become a profession.

For years after the government first began in 2001 to twist the arms of anyone who looked after an unrelated child to register with the schools, the numbers so doing fell. Kind but clueless neighbours stopped looking after little ones, who were instead herded into formal nurseries or handed over to one of the ever-fewer registered child-minders. The decline in the number of people taking in children now appears to have halted. According to data released by the Office for Standards in Education on October 27th, the number of registered child-minders reached its lowest point in September 2010 and has since recovered slightly.

The new lot are certainly better qualified. In 2010 fully 82% of nursery workers held diplomas notionally equivalent to A-levels, the university-entrance exams taken mostly by 18-year-olds, up from 56% seven years earlier, says Anand Shukla of the Daycare Trust, a charity. Nurseries staffed by university graduates tend to be rated highest by inspectors, increasing their appeal to the pickiest parents. As a result, more graduates are being recruited.

But professionalization has also pushed up the price of child care, defying even the economic depression. A survey by the Daycare Trust finds that a full-time nursery place in England for a child aged under two, who must be intensively supervised, costs £194 ($310) per week, on average. Prices in London and the south-east are far higher. Parents in Britain spend more on child care than anywhere else in the world, according to the OECD, a think-tank. Some 68% of a typical second earner's net income is spent on freeing her to work, compared with an OECD average of 52%.

The price of child care is not only eye-watering, but has also become a barrier to work. Soon after it took power the coalition government pledged to ensure that people are better off in work than on benefits, but a recent survey by Save the Children, a charity, found that the high cost of day care prevented a quarter of low-paid workers from returning to their jobs once they had started a family. The government pays for free part-time nursery places for three-and four-year-olds, and contributes towards day-care costs for younger children from poor areas. Alas, extending such an aid during stressful economic times would appear to be anything but child’s play.

1. Which of the following is true according to the first paragraph?
A.Nursery education plays a leading role in one’s personal growth.
B.Pregnant women have to work to lighten families’ economic burden.
C.Children in nursery have to take uniform nation courses.
D.The supervision of the state makes child care professional.
2. It can be learned from Paragraph 2 and 3 that ___________.
A.the registered child-minders are required to take the university-entrance exams
B.the number of registered child-minders has been declining since 2001
C.anyone who looks after children at home must register with the schools
D.the growing recognition encourages more graduates to work as child-minders
3. The high price of child care __________.
A.prevents mothers from getting employed
B.may further depress the national economy
C.makes many families live on benefits
D.is far more than parents can afford
4. What is the author’s attitude towards the professionalization of child care?
A.Objective.B.Skeptical.C.Supportive.D.Biased.
5. Which of the following would be the subject of the text?
A.The professionalization of child care has pushed up its price.
B.The high cost of child nursing makes many mothers give up their jobs.
C.The employment of more graduates makes nurseries more popular.
D.Parents in Britain pay most for child nursing throughout the world.
2022-03-11更新 | 1057次组卷 | 6卷引用:新疆乌鲁木齐市实验学校2023-2024学年高二上学期1月期末英语试题
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2 . Revealing the source of Jupiter’s x-ray auroral flares


Abstract

Jupiter’s rapidly rotating, strong magnetic field provides a natural laboratory that is key to understanding the dynamics (动力学) of high-energy plasmas (等离子体). Spectacular auroral (极光的) X-ray flares (耀斑) are diagnostic of the most energetic processes governing magnetospheres but seemingly unique to Jupiter. Since their discovery 40 years ago, the processes that produce Jupiter’s X-ray flares have remained unknown. Here, we report simultaneous (同时的) in situ satellite and space-based telescope observations that reveal the processes that produce Jupiter’s X-ray flares, showing surprising similarities to terrestrial ion aurora. Planetary-scale electromagnetic waves are observed to modulate (调节) electromagnetic ion cyclotron waves, periodically causing heavy ions to precipitate and produce Jupiter’s X-ray pulses. Our findings show that ion aurorae share common mechanisms across planetary systems, despite temporal, spatial, and energetic scales varying by orders of magnitude.

INTRODUCTION

Aurorae, observed from planetary polar regions across the solar system, are displays of light that are produced when energetic particles precipitate along magnetic field lines and transfer their energy to the atmosphere. Jupiter’s soft x-ray aurorae are produced by energetic [~ (MeV) (电子伏)] heavy ions (S and O), originally from the moon Io’s (木卫一的) volcanic activities. The dynamic X-ray emissions often pulse with a regular beat of a few tens of minutes. The spectacular quasi-periodic (准周期性的) auroral pulsations at Jupiter have also been observed in ultraviolet (UV), infrared, and radio emissions. The X-ray aurorae are predominately confined (主要局限于) to the region poleward of Jupiter’s main aurora, connecting to Jupiter’s outer magnetosphere via magnetic field lines. The mapping of the emissions leads to the suggestion that the particle precipitations were driven by magnetic reconnection. However, observations show that the x-ray pulsations last for several Jupiter days or longer, evidencing that the driver may not be a transient process like magnetic reconnection.

To date, 40 years after their discovery, the mechanisms that cause these X-ray aurorae remain unknown. Simultaneous measurements of the magnetospheric environment and the auroral emissions are critical to revealing their driving mechanisms. Here, we present observations of Jupiter’s unique x-ray aurorae with simultaneous in situ measurements from the magnetosphere. In this study, we reveal the physical driver for Jupiter’s pulsating x-ray emissions by analyzing simultaneous in situ measurements from Juno and remote spectroscopic imaging by XMM-Newton telescope (XMM,牛顿卫星) during 16 and 17 July 2017. XMM’s European Photon Imaging Camera (EPIC-pn and MOS) instruments provided spatial, spectral, and timing data of Jupiter for a continuous 26-hour (~2.6 Jupiter rotations) observation from 18:26 UT on 16 July to 22:13 UT on 17 July, which was shifted to account for the ~46-min light travel time between Jupiter and Earth. This XMM observation was planned to coincide with the time when NASA’s Juno spacecraft was moving from 62 to 68 RJ (1 RJ = 71 492 km) radially away from the planet in the Southern Hemisphere in the predawn sector between ~0400 and 0430 magnetospheric local time (MLT).

Ionosphere-magnetosphere (电离层) mapping from previous observations suggested that the origins of Jupiter’s X-ray auroral pulsations occurred at these distances from the planet. Juno provided contemporaneous (同时发生的) in situ measurements from the plasma sheet only when Jupiter’s north magnetic pole tilted to Earth. Therefore, we focus on the northern aurora, for which Juno’s in situ measurements detail what was happening in the plasma sheet during the X-ray pulses. At Jupiter, the analysis of these comparisons between in situ and remote sensing observations is more complex than at Earth. At Earth, during the time scale of an auroral event, typically tens of minutes, a spacecraft in the terrestrial magnetosphere usually travels little (e.g., hundreds of kilometers) in comparison to the spatial scale of a magnetospheric event (e.g., several Earth radii) that would cause a large auroral brightening so that this in situ spacecraft could be magnetically connected to the aurora region over the full auroral lifetime. This is not true for Jupiter, because the footprint of the aurora (which is rotating with Jupiter) with respect to Juno’s location changes substantially during an observation. There are also substantial travel times (a few tens of minutes) along the magnetic field expected from the outer magnetosphere to the Jovian aurora. Therefore, the correlation between a single outer magnetosphere event in Jupiter’s in situ measurements and a single auroral pulse cannot be expected on a one-to-one level basis. Instead, a series of successive events are required to draw reliable careful correlations, with the regular periodicity of the x-ray flares, providing an invaluable diagnostic signature of the source process.

(Adapted from an essay on Science.)

1. What does the essay focus on?
A.The X-ray pulses happening on Jupiter.
B.The formation of the aurora in the pole of Jupiter.
C.The ways to teach people how to appreciate auroras.
D.The process of detecting the X-ray pulses on Jupiter.
2. What will the author present in the next content of the essay?
A.Their conclusions.B.Their measure to do the research.
C.Discussion of some problems of preciseness.D.Their acknowledgements.
3. The word “infrared” is underlined and in Italics. What is the meaning of the word?
A.辐射B.红外线技术的C.太阳风D.红外线
4. Which of the followings is NOT TRUE about the auroral flares on Jupiter?
A.The strong magnetic is a good breakthrough point to research the auroral flares.
B.The X-ray pulses will last for several days on Jupiter.
C.The soft X-rays are caused by high-energy ions.
D.The X-ray pulses beat regular on Jupiter.
2021-12-10更新 | 980次组卷 | 3卷引用:新疆维吾尔自治区乌鲁木齐市第二十中学2023-2024学年高三上学期12月月考英语试题
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