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2014-01-09
What Do They Do?
1、Read the patterns of wide and narrow rings in wood from different trees. They match patterns from different trees to identify the year that a tree produced a particular ring. This process of matching across specimens is "cross-dating."
2、Estimate archaeological ages. Andrew Ellicott Douglas was the first dendrochronologist. He became famous for his studies of Pueblo ruins, which he analyzed by cross-dating, the tool that he developed as his "key to prehistoric chronology."
3、Predict future drought, flood, and other conditions. A. E. Douglas proposed that tree rings would be allow us to measure past climate and, potentially, to predict drought and flood over a period of years, which would provide economic advantage.
What Causes Variations in Tree Rings?
When conditions encourage growth, a tree adds extra tissue and produces a thick ring. In a discouraging year, growth is slowed and the tree produces a thin ring. Much of the variation in tree rings is due to variations year-to-year in:
1、Higher springtime temperature. If spring starts early, the growing season is likely to be longer than usual, causing a tree to have a wider ring.
2、Lower springtime temperature. A late spring is likely to shorten the growing season, causing a tree to have a narrower tree ring.
3、Abundant rainfall increases growth, producing a wider ring.
4、Drought decreases growth, producing a narrower ring.
5、Species of tree do differ in their response to weather changes. One might respond strongly to changes in overall rainfall, another might be more sensitive to the amount of rain during the late summer, and another to a temperature change that alters the length of the growing season.
6、Crowding from neighboring trees. This causes a series of narrow rings. Crowding is suspected when the series of narrow rings is more than three, because droughts are usually only one to three years.
7、If the rings are narrow on one side of a tree with wide rings on the other, the tree was crowded on the side of the tree where the rings are narrow.
8、A series of many narrow rings followed immediately by wide rings probably means that an encroaching neighbor died, releasing the crowded tree into a growth spurt.
9、Fire scars suggest past forest fires. The number of annual rings between fire scars shows the period between fires.
10、Scars due to insect plagues indicate insect infestations.
It’s no surprise that a warming climate is melting the world’s glaciers and polar ice. But no one expected it to happen this fast.
Even in better times, the Chacaltaya ski area was no competition for Aspen. Set in a bleak valley high in the Andes mountains of Bolivia, it offered a half-mile (one kilometer) swoop downhill, a precarious ride back up on a rope tow, and coca-leaf tea for altitude headaches. At 17,250 feet (5,260 meters), after all, Chacaltaya was the highest ski area in the world. “It gave us a lot of glory,” says Walter Laguna, the president of Bolivia’s mountain club. “We organized South American championships—with Chile, with Argentina, with Colombia.”
The glory days are over. Skiing at this improbable spot depended on a small glacier that made a passable ski run when Bolivia’s wet season dusted it with snow. The glacier was already shrinking when the ski area opened in 1939. But in the past decade, it’s gone into a death spiral.
By last year all that remained were three patches of gritty ice, the largest just a couple of hundred yards (200 meters) across. The rope tow traversed boulder fields. Laguna insists that skiing will go on. Perhaps the club can make artificial snow, he says; perhaps it can haul in slabs of ice to mend the glacier. But in the long run, he knows, Chacaltaya is history. “The process is irreversible. Global warming will continue.”
The dinosaurs were wiped out 65 million years ago by at least two meteorite impacts, rather than a single strike, a new study suggests.
Previously, scientists had identified a huge impact crater in the Gulf of Mexico as the event that spelled doom for the dinosaurs.
Now evidence for a second impact in Ukraine has been uncovered.
This raises the possibility that the Earth may have been bombarded by a whole shower of meteorites.
The new findings are published in the journal Geology by a team lead by Professor David Jolley of Aberdeen University.
When first proposed in 1980, the idea that a meteorite impact had killed the dinosaurs proved hugely controversial. Later, the discovery of the Chicxulub Crater in the Gulf of Mexico, US, was hailed as "the smoking gun" that confirmed the theory.
Double trouble
The discovery of a second impact crater suggests that the dinosaurs were driven to extinction by a "double whammy" rather than a single strike.
The Boltysh Crater in Ukraine was first reported in 2002. However, until now it was uncertain exactly how the timing of this event related to the Chicxulub impact.
In the current study, scientists examined the "pollen and spores" of fossil plants in the layers of mud that infilled the crater. They found that immediately after the impact, ferns quickly colonised the devastated landscape.
Ferns have an amazing ability to bounce back after catastrophe. Layers full of fern spores - dubbed "fern spikes" - are considered to be a good "markers" of past impact events.
However, there was an unexpected discovery in store for the scientists.
They located a second "fern spike" in a layer one metre above the first, suggesting another later impact event.
Professor Simon Kelley of the Open University, who was co-author on the study, said: "We interpret this second layer as the aftermath of the Chicxulub impact."
This shows that the Boltysh and Chicxulub impacts did not happen at exactly the same time. They struck several thousand years apart, the length of time between the two "fern spikes".
Uncertain cause
Professor Kelley continued: "It is quite possible that in the future we will find evidence for more impact events."
Rather than being wiped out by a single hit, the researchers think that dinosaurs may have fallen victim to a meteorite shower raining down over thousands of years.
What might have caused this bombardment is highly uncertain.
Professor Monica Grady, a meteorite expert at the Open University who was not involved in the current study, said: "One possibility might be the collison of Near Earth Objects."
Recently, Nasa launched a program dubbed "Spaceguard". It aims to monitor such Near Earth Objects as an early warning system of possible future collisons.
志存高遠(yuǎn),成功坦途
It is well that young men should begin at the beginning and occupy the most subordinate positions. Many of the leading businessmen of Pittsburgh had a serious responsibility thrust upon them at the very threshold of their career. They were introduced to the broom, and spent the first hours of their business lives sweeping out the office. I notice we have janitors and janitresses now in offices, and our young men unfortunately miss that salutary branch of business education. But if by chance the professional sweeper is absent any morning, the boy who has the genius of the future partner in him will not hesitate to try his hand at the broom. It does not hurt the newest comer to sweep out the office if necessary. I was one of those sweepers myself.
Assuming that you have all obtained employment and are fairly started, my advice to you is “aim high”。 I would not give a fig for the young man who does not already see himself the partner or the head of an important firm. Do not rest content for a moment in your thoughts as head clerk, or foreman, or general manager in any concern, no matter how extensive. Say to yourself, “My place is at the top.” Be king in your dreams.
And here is the prime condition of success, the great secret: concentrate your energy, thought, and capital exclusively upon the business in which you are engaged. Having begun in one line, resolve to fight it out on that line, to lead in it, adopt every improvement, have the best machinery, and know the most about it.
The concerns which fail are those which have scattered their capital, which means that they have scattered their brains also. They have investments in this, or that, or the other, here there, and everywhere. “Don’t put all your eggs in one basket.” is all wrong. I tell you to “put all your eggs in one basket, and then watch that basket.” Look round you and take notice, men who do that not often fail. It is easy to watch and carry the one basket. It is trying to carry too many baskets that breaks most eggs in this country. He who carries three baskets must put one on his head, which is apt to tumble and trip him up. One fault of the American businessman is lack of concentration.
To summarize what I have said: aim for the highest; never enter a bar room; do not touch liquor, or if at all only at meals; never speculate; never indorse beyond your surplus cash fund; make the firm’s interest yours; break orders always to save owners; concentrate; put all your eggs in one basket, and watch that basket; expenditure always within revenue; lastly, be not impatient, for as Emerson says, “no one can cheat you out of ultimate success but yourselves.”
成功之道
年輕人創(chuàng)業(yè)之初,應(yīng)該從底層干起,這是件好事。匹茲保有很多商業(yè)巨頭,在他們創(chuàng)業(yè)之初,都肩負(fù)過(guò)“重任”:他們以掃帚相伴,以打掃辦公室的方式度過(guò)了他們商業(yè)生涯中初的時(shí)光。我注意到我們現(xiàn)在辦公室里都有工友,于是年輕人就不幸錯(cuò)過(guò)了商業(yè)教育中這個(gè)有益的環(huán)節(jié)。如果碰巧哪天上午專職掃地的工友沒(méi)有來(lái),某個(gè)具有未來(lái)合伙人氣質(zhì)的年輕人會(huì)毫不猶豫地試著拿起掃帚。在必要時(shí)新來(lái)的員工掃掃地也無(wú)妨,不會(huì)因?yàn)槎惺裁磽p失。我自己就曾經(jīng)掃過(guò)地。
假如你已經(jīng)被錄用,并且有了一個(gè)良好的開(kāi)端,我對(duì)你的建議是:要志存高遠(yuǎn)。一個(gè)年輕人,如果不把自己想象成一家大公司未來(lái)的老板或者是合伙人,那我會(huì)對(duì)他不屑一顧。不論職位有多高,你的內(nèi)心都不要滿足于做一個(gè)總管,領(lǐng)班或者總經(jīng)理。要對(duì)自己說(shuō):我要邁向頂尖!要做就做你夢(mèng)想中的國(guó)王!
成功的首要條件和大秘訣就是:把你的精力,思想和資本全都集中在你正從事的事業(yè)上。一旦開(kāi)始從事某種職業(yè),就要下定決心在那一領(lǐng)域闖出一片天地來(lái);做這一行的領(lǐng)導(dǎo)人物,采納每一點(diǎn)改進(jìn)之心,采用優(yōu)良的設(shè)備,對(duì)專業(yè)知識(shí)熟稔于心。
一些公司的失敗就在于他們分散了資金,因?yàn)檫@就意味著分散了他們的精力。他們向這方面投資,又向那方面投資;在這里投資,在那里投資,到處都投資?!安灰阉械碾u蛋放在一個(gè)籃子里”的說(shuō)法大錯(cuò)特錯(cuò)。我要對(duì)你說(shuō):“把所有的雞蛋都放在一個(gè)籃子里,然后小心地看好那個(gè)籃子。”看看你周圍,你會(huì)注意到:這么做的人其實(shí)很少失敗??垂芎蛿y帶一個(gè)籃子并不太難。人們總是試圖提很多籃子,所以才打破這個(gè)國(guó)家的大部分雞蛋。提三個(gè)籃子的人,必須把一個(gè)頂在頭上,而這個(gè)籃子很可能倒下來(lái),把他自己絆倒。美國(guó)商人的一個(gè)缺點(diǎn)就是不夠?qū)Wⅰ?/p>
把我的話歸納一下:要志存高遠(yuǎn);不要出入酒吧;要滴酒不沾,或要喝也只在用餐時(shí)喝少許;不要做投機(jī)買賣;不要寅吃卯糧;要把公司的利益當(dāng)作自己的利益;取消訂貨的目的永遠(yuǎn)是為了挽救貨主;要專注;要把所有的雞蛋放在一個(gè)籃子里,然后小心地看好它;要量入為出;后,要有耐心,正如愛(ài)默生所言,“誰(shuí)都無(wú)法阻止你終成功,除非你自己承認(rèn)自己失敗?!?/p>
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