【Native Speaker每日综合训练—44系列】【44-16】科技 Alcohol

Going

内容：古月小破烂 编辑：going

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本期关于alcohol~~文章都比较长，大家坚持! ~enjoy~

Part I: Speaker

Select Few Can Truly Drink to Their Health

If you like to wind down with a drink, you've perhaps also rationalized the act with this often repeated claim: <<News Anchor: "You don't have to feel guilty about imbibing a little red or white: in small amounts it is good for your heart.">> But a new study finds that alcohol's supposed benefit may in fact only be available to certain people—who happen to have the right genes.

Researchers studied 600 Swedish men and women with heart disease, and compared them to some 3,000 healthy volunteers. They asked the subjects about their drinking, measured their blood cholesterol, and sequenced each subject's version of a gene that governs the transport of cholesterol to the liver.

Turns out, moderate drinking—a couple of drinks a day—appeared to lower heart disease risk overall by 20 percent. But subjects who had a specific variant of that cholesterol transport gene, and tipped back a few? They had an 80 percent reduction in heart disease risk. And the gene variant isn't protective by itself; only when combined with booze. The results appear in the journal Alcohol. [Kirsten Mehlig et al: CETP TaqIB genotype modifies the association between alcohol and coronary heart disease: The INTERGENE case-control study]

Unfortunately, only about 15 percent of us have this variant. Study author Dag Thelle, of the University of Gothenburg, says that past studies which found what looks statistically like a slight heart benefit of moderate drinking in large populations, could actually just be detecting this huge alcohol benefit, in the small, lucky gene group. While the vast majority of drinkers get no benefit at all.

So any message here for drinkers? <<"In my view there is not. Not at this time. It's far too early to say anything.">> The study's too small, he says, and has to be repeated. However, <<"Most of my friends they claim they drink moderately. But when I look at them I see there's quite a large variation.">> Before you order that next round, you might wanna take that idea to heart.

Source: Scientific America

http://www.scientificamerican.com/podcast/episode/select-few-can-truly-drink-to-their-health/

[rephrase 1, 2’11]

Going

Part II: Speed

Wine Becomes More Like Whisky as Alcohol Content Gets High

Superstar wine critic Robert Parker’s legacy—a zinfandel with 17 percent alcohol?

By Jennifer Frazer | February 27, 2014

[Time 2]

It's not your imagination. Wine really has gotten boozier.

In the past two decades the maximum alcohol content of wine has crept up from about 13 percent to, in some cases, northward of 17 percent, a side effect of the growing popularity of wines with richer fruit flavor. The intoxication inflation has gotten so bad that wine scientists have begun to bioprospect for wild yeasts that turn a smaller quantity of the sugar in grape juice into alcohol during fermentation than does the yeast Saccharomyces cerevisiae—humanity’s partner in inebriation for thousands of years—but which can still produce a fine, finished wine

A team of scientists from Australia and Spain now has apparently accomplished this enological first, having identified a new, wild yeast that reduced alcohol concentrations in Shiraz wine by 1.6 percent. The yeast may even improve or at least diversify the quality of the wines it helps make. Although many people enjoy stiffer wines, others are concerned by the effect of so much alcohol on these wines’ quality, not to mention imbibers’ health, and would welcome an option that provides the flavors associated with high-alcohol wines without the accompanying effects on blood–alcohol content.

The recent surge in wine's punch is largely a result, scientists say, of a fashion for deeply colored wines with fewer “green” qualities and more bright, ripe, fruity flavors. As New World wines in this style have drawn more fans, even European winemakers accustomed to making lower-alcohol wines in less ripe styles are beginning to follow suit. But producing wines with those flavors means letting grapes hang longer on the vine, and with longer hang times comes bigger sugar. The more sugar the wine yeast S. cerevisiae has to work with, the more alcohol it will make.

[294 words]

[Time 3]

According to Matt Stamp, master sommelier and education director at the Guild of Sommeliers, the trend has its origins in wine expert Robert Parker's lauding of the 1982 Bordeaux vintage, but other critics and high-profile wine magazines have followed suit in giving high praise to full-bodied, concentrated, high-alcohol wines. “Those are the wines that are making 100-point scores,” he says.

More alcohol can also counterproductively dampen wine's characteristic bouquet. Most of the volatile components of wine—the chemicals responsible for the many fruity, herbaceous or earthy aromas—become more reluctant to diffuse from liquid to air in higher-alcohol wine. Stiffer wines may also incur higher taxes. And then, of course, there are alcohol's well-documented effects on waistlines, health and well-being. “You want to be able to have a glass of wine with lunch or dinner and be able to still function afterwards,” says James Kennedy, chair of the Department of Viticulture and Enology at California State University, Fresno, and president of the American Society for Enology and Viticulture, “and I think with these creeping alcohol concentrations people are concerned generally about ‘Are we drinking too much alcohol as a society?’ and ‘Should we perhaps try to tone it down a little bit?’”

Stamp agrees, and sees other problems. “Wines that are 15 percent alcohol and more are not exactly wines you can make it through two or three bottles of over the course of a meal with friends,” he says. “They're wines you might want to drink a glass of, but they're not wines that respond well to a lot of the more delicate styles of food we see in modern restaurants.” Sommeliers, he says, have begun pushing consumers to consider more moderate-alcohol wines with higher acidity and more delicate character that pair better with many foods, he says, and some have embraced the suggestions. But for those who prefer big, bold wines and would still like to be able to drive home, science may have a solution.

[328 words]

[Time 4]

Finding ways to produce weaker dry wines from riper grapes has proved a challenge. Although there are more than 100 varieties of winemaking yeast—all S. cerevisiae—each of them produces virtually the same amount of alcohol given the same amount of sugar. Winemakers could stop fermentation early to reduce alcohol, but the unprocessed sugar would remain and make producing dry wine impossible.

Winemakers and scientists have already tried a variety of approaches to promote or preserve ripe flavors while reducing alcohol: clipping the leaves covering grape clusters, for instance, or changing irrigation practices or artificially removing alcohol from finished wine, all of which can affect flavor. The success of these strategies has been limited.

Alan Bakalinsky, associate professor of food science and technology at Oregon State University, who's long studied wine yeast, says that winemakers have tried to tinker with S. cerevisiae for years to get it to reduce it's alcohol production efficiency. But doing so can alter the yeast's winemaking abilities or cripple it, and certain methods of doing it may involve genetic modification that consumers may not like. Finding a wild yeast that already has the desired suite of traits would be a simple and elegant shortcut, he says.

So the Australian and Spanish team of scientists tried just this approach. “That was the motivation,” says Cristian Varela, senior research scientist at The Australian Wine Research Institute (AWRI) and a lead author on the study that sought new yeasts: “trying to find something simple that the winemakers could use easily in the winery.”

[256 words]

[Time 5]

This idea has been tried before, but no one had found a wild yeast that could lower alcohol without hurting quality. In the new attempt researchers began by creating a panel of 50 strains of wild yeasts from 40 species collected from grapes, samples from fermenting wines, fermented food or soil. They then subjected the panel to a battery of tests to see whether the wild yeasts could lower alcohol contents in finished wine. They inoculated standardized wine yeast chow with their experimental organisms and waited several days. They then added S. cerevisiae to finish the job, because wild yeasts can't consume all the sugar alone. Of the 50, only four strains produced less alcohol than S. cerevisiae alone did, and of those, one strain of Metschnikowia pulcherrima isolated from wine grapes produced the least, as the team reported online December 27 ahead of print in Applied and Environmental Microbiology. When they tested this yeast with real wine grapes and juice, it managed an alcohol drop of 0.9 percent in chardonnay and 1.6 percent in Shiraz, and the wine had chemical profiles consistent with good wine, they reported. “If you ask anyone in the industry a drop of this magnitude is very, very interesting for them,” Varela says. He has already been contacted by about 10 interested Australian winemakers and one from the U.S., although a yeast manufacturer would have to take charge of commercial production, a possibility he is exploring

As a bonus, wine made this way might add interesting flavor complexity to wine. The dual-yeast wines had more “higher alcohols”—alcohol molecules that are larger and more structurally complex than ethanol (not the same as overall alcohol content)—than the control, but they were present in quantities that would be expected to enhance the olfactory complexity of the wine. The wine also had fewer “volatile acids,” which generally produce undesirable odors. The chardonnay had more esters, primarily two chemicals generally described as producing “pear” and “banana” flavors. But the chardonnay also had 6.5 times higher levels of ethyl acetate, a chemical said to convey “nail polish remover” at such concentrations. This level is unacceptable, but in the Shiraz the ethyl acetate concentration was low enough to add “desirable complexity.” “If you think of the thousands of winemakers in the United States, a lot of them want complexity in wine, it's an important part of it,” Kennedy, who was not involved in the research, says. “This in my mind appeals to that approach to winemaking: different yeast are going to create different compounds, and it adds to the complexity of wine potentially. And then if you have along with that the lower alcohol, that's a win–win.”

[448 words]

[Time 6]

Work to develop the new yeast remains unfinished—particularly in understanding what conditions favor ethyl acetate production. Winemakers would be less skeptical of the new yeast, Bakalinsky says, if they could feel confident they knew how to avoid the production of such undesirable flavors. The scientists would also be well advised, Kennedy says, to figure out exactly where all the sugar not being converted into ethanol is going.

But so far, informal taste tests have been promising. In a small tasting at AWRI six of eight people who sampled the wine made with M. pulcherrima deemed it better than the control whereas two of the eight said the result was more or less the same. Varela's own impression of the Shiraz was that it was fruitier and more complex than the control wine.

It's also possible there's another strain of yeast of this or another species awaiting discovery that's even better at reducing alcohol without harming quality, because variation even within a given species of yeast seems to be considerable. Of the six strains of M. pulcherrima Varela and his colleagues tested only one was able to significantly reduce alcohol in both chardonnay and Shiraz wines. If this variability holds for other species, M. pulcherrima may be just the first of many new yeast tools available to winemakers interested in preventing their products from straying uncomfortably close to the realm of plastic jugs and flaming desserts.

[236 words]

Source: Scientific America

http://www.scientificamerican.com/article/wine-becomes-more-like-whisky-as-alcohol-content-gets-high/   

Going

Part III: Obstacle

In Search of a Cure for the Dreaded Hangover
Can science help defeat the physical aftereffects of drinking too much alcohol—if not the regrets?
By Fred Minnick | March 17, 2014

[Paraphrase 7]
Since the invention of fermented beverages, curing the dreadful aftermath of overimbibing them has been one of humanity's morning-after quests. Ancient Greeks ate sheep lungs and two owl eggs to cure such a hangover, a cure tweaked by Roman Gaius Plinius Secundus, better known as Pliny the Elder, who suggested raw owl eggs or a fried canary. Sicilians recommended dried bull penis although Mongolians prefer tomato juice and pickled sheep’s eyes.

But what do scientists say? After all, hangovers cost the U.S. alone some $224 billion a year in workplace productivity declines, drinking-related health care expenses, law enforcement, and motor vehicle accident and fatality costs, according to the U.S. Centers for Disease Control.

Beyond the fiscal damage, scientists take the hangover seriously for more reasons than helping postdrinking pain. “Studying alcohol can tell us how the body works in its normal fashion,” says Michael Oshinsky, director of preclinical research at Thomas Jefferson University in Philadelphia, who studies hangovers to better understand migraines. When the body is pushed to its physical limits to metabolize alcohol, it helps show what causes headaches—one of the common components of the hangover.

Hangover cause
Shortly after a person starts consuming an alcoholic drink, the liver gets to work. The enzyme alcohol dehydrogenase (ADH) metabolizes the ethanol (that's the type of alcohol in alcohol) into toxic acetaldehyde. From there the liver enzyme aldehyde dehydrogenase (ALDH) metabolizes acetaldehyde into acetate, a less toxic compound that breaks down into water and carbon dioxide. According to the Department of Health and Human Services, some alcohol metabolism also occurs in the pancreas, gastrointestinal tract and the brain, but the liver does the bulk of the work with its two enzymes.

The problem is: all this takes time and, the next day, the drinker suffers.

That dreadful feeling the next day is the condition often called a hangover, which the journal Alcohol and Alcoholism characterizes as “general misery” with symptoms of drowsiness, concentration problems, dry mouth, dizziness, gastrointestinal complaints, sweating, nausea, hyperexcitability and anxiety. Most of these symptoms have been linked to elevated levels of acetaldehyde.

In a 2000 study “The Role of Acetaldehyde in Actions of Alcohol,” which was published in Alcoholism: Clinical & Experimental Research study, researchers determined elevated acetaldehyde levels caused increased skin temperature, facial flushing, increased heart rate, lower blood pressure, dry mouth, nausea and headache. The researchers reported that heavy drinking leads to elevated acetaldehyde levels, which leads to inhibited ALDH enzymes, and in turn causes these adverse effects. The alcohol does not properly metabolize.

Japanese researchers further studied the role of acetaldehyde but specifically in Japanese workers whose bodies could not break down the alcohol. Specifically, they studied participants with the allele (mutant gene) aldehyde dehydrogenase-2 and those with inactive ALDH2. This enzyme mutation is what leads many of Asian descent to turn red when drinking. The study concluded acetaldehyde may be the culprit behind hangovers after discovering acetaldehyde quickly metabolized with normal ALDH enzymes, but participants with the enzyme mutation experienced cardiovascular complications, drowsiness, nausea, asthma, facial flushing and were at greater risk for hangovers.

Whereas this study was limited to Japanese subjects, prominent researchers continue to note that acetaldehyde likely causes the hangover. In a 2014 Food & Function paper, “Effects of Herbal Infusions, Tea and Carbonated Beverages on Alcohol Dehydrogenase and Aldehyde Dehydrogenase Activity,” Chinese scientists determined acetaldehyde is the “primary mediator” of the hangover’s “adverse effects,” adding the compound is linked to lesions and tumors of the large bowel. These scientists also said the second metabolite, acetate, may provide protective health effects associated with the regular moderate consumption of alcohol.

But research in hungover rats suggests that the buildup of acetate is not a good thing, and may be responsible for hangovers. “Because acetaldehyde is a very reactive compound and toxic to the body, your body has an efficient mechanism for handling that. It changes it into a very stable compound, which is acetate,” Oshinsky says. “Your body is filled with acetate and there are lots of other biological processes that have acetate as a by-product.” Too much acetate can trigger a nasty headache. Oshinsky published his work in the peer-reviewed PLoS ONE in December 2010. His findings are backed up in principle by dialysis research. Doctors working with patients with failed kidneys used sodium acetate to buffer the dialysate, one of the two fluids in dialysis used to clean the blood, and discovered significant headaches in about 30 percent of the patients. After the dialysis researchers switched the buffer from sodium acetate to sodium borate, Oshinsky says, the headache rate dropped to less than 2 percent. This evidence supports the fact that acetate, not acetaldehyde, causes the hangover, he adds, or at least the hangover headache.

But another study suggests the alcohol’s congeners [related substances] are more likely the hangover perp than the metabolites. “[Congeners] occur in alcoholic beverages, mostly as a result of the processes used in fermenting and aging,” says Damaris Rohsenow, research professor at the Behavioral and Social Sciences Center for Alcohol and Addiction Studies at Brown University School of Public Health, which makes them more prevalent in barrel-aged beverages such as brandy, wine and whiskey. Congeners include acetaldehyde itself as well as acetone, fusel oil, furfural, methanol's metabolites, polyphenols, histamines, esters, tannins, amines and amides, among others. All have been linked to the alcohol’s intoxicating effects.

According to Rohsenow’s “Intoxication with Bourbon versus Vodka: Effects on Hangover, Sleep, and Next-Day Neurocognitive Performance in Young Adults” published in Alcoholism: Clinical & Experimental Research, healthy heavy drinkers 21 to 33 participated in two drinking nights after an acclimatization night, building a mean blood alcohol level of 0.11 percent on vodka or bourbon one night with matched placebo the other night. The study found congeners increased hangover severity, with people feeling worse after bourbon. Bourbon whiskey has 37 times the congeners as vodka because bourbon ages in oak barrels, leaching out various molecules. But it’s not all bad news for bourbon. “Some whiskey congeners, particularly butanol, actually protect the stomach lining from damage [gastric mucosal damage], so potentially [it] might protect against feeling nauseous,” Rohsenow says

As for the hangover, Rohsenow says ethyl alcohol itself may still be the primary culprit. “Our study comparing beverages with high versus very low congener content showed most of the effect of drinking on hangover was due to the ethanol itself, with the other chemicals increasing hangover significantly but accounting for a much smaller percentage of the effect on hangover,” she says.

Hangover cures
Now the part you’ve been waiting for: Modern scientists have almost as many cures for hangovers as have been handed down from antiquity. Last year Chinese researchers from Sun Yat-sen University in China, the Food & Function paper co-authors, studied 57 different herbal and carbonated drinks' impacts on the enzymes that break down and rid the body of acetaldehyde and acetate, respectively. They discovered that some drinks, namely an herbal infusion called “Huo ma ren,” which consists of hemp seeds, increased ADH levels. That accelerated the breakdown of the alcohol in the first place but also inhibited the enzyme responsible for getting rid of acetate. The study showed that although green teas are rich in antioxidants, they “seriously prohibit” the metabolism of alcohol. The researchers wrote it’s better not to drink tea products during or after excessive alcohol consumption.

On the other hand, four beverages increased ADH and ALDH activity, helping to metabolize the toxins more quickly. Xue bi, which is similar to the popular soft drinks Sprite and 7-Up, showed the greatest increased ALDH activity and breakdown of acetaldehyde. The paper said the common soft drink additive taurine promotes efficient elimination of acetaldehyde. Thus, this research pointed toward Sprite or other soft drinks with taurine as being the optimal hangover cure.

Sticking to the liquid cures, Oshinsky’s study credits a morning cup of coffee and an aspirin. “The way we block the headache in the rat is five hours after we exposed them to alcohol, we gave them the caffeine,” Oshinsky says. “Nonsteroidal anti-inflammatory drugs also block the headache in the rat and those have a much longer half-life, so you can treat the animal much earlier, three or four hours before the headache.”

Moving past the over-the-counter antidotes, University of California, Los Angeles, chemical engineer Yunfeng Lu is using nanotechnology to mimic the liver’s enzymes and speed the elimination of alcohol from the body. Lu’s team showed that polymer capsules just tens of nanometers in diameter containing enzymes that break down alcohol could reduce blood alcohol levels in intoxicated mice. The team published their work in Nature Nanotechnology. Lu plans further research before testing this technology on humans but indicates the nanocomplex has far greater implications than just curing the hangover. In the study Lu concluded, “Considering the vast library of enzymes that are currently or potentially available, novel classes of enzyme nanocomplexes could be built for a broad range of applications."
[1486 words]

[The rest]
It's complicated
But not everybody is ready to hail the nanomedicine as the future and decisive cure for all things, especially doctors who specialize in the hangover.

Anesthesiologist Jason Burke runs the Las Vegas–based mobile clinic “Hangover Heaven” and treats hangovers with IV fluids, the nausea medication Zofran, pain and inflammation drug Toradol, and a proprietary blend of vitamins. He remains skeptical of any and all hangover studies. “My biggest issue with hangover research is the way that most of these studies view hangovers,” he says. “When you actually look at the severity of the hangovers in most of these studies, they're not that bad.” He adds that “Las Vegas–sized” hangovers would not be considered ethical or safe by the review boards that approve medical experiments. Studies based on rats or humans who drank four beers won’t help the 24-beer client with a 0.3 blood alcohol level, he notes.

Still, Burke admits Lu's hangover nanopill intrigues him. “People want to feel better now,” he says. “This is America, the land of the magic pill.”
[176 words]

Source: Scientific America
http://www.scientificamerican.com/article/in-search-of-a-cure-for-the-dreaded-hangover/

ryanzhaobo

啊…现在听这听力还是很蛋疼啊

tantan08

1:45
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2:25
3:11
1:34

Dobebabe

1, 2'16
2, 2'28''
3, 1,53''
4, 3'11''
5, 1'44''

6, 12'52''
前两天忘记读过之后忘记回帖了，只记在印象笔记里。

conglomerator

Time 2: 1:48

Nowadays, alcohol concentration in wine are getting higher and higher because certain flavor of wine is becoming more popular among people.

Time 3: 1:51

The elevating alcohol concentration has some impacts.

Time 4: 00:45

Some methods have been tried out to lower the alcohol concentration without influence the wine’s flavor.

Time 5: 1:16

A method has been proved to be effective on reducing alcohol concentration and in addition other properties are added to the wine to. There is potential opportunity to commercialize this method.

Time 6: 00:40

The test isn’t over yet. More tests are conducted on the changed flavors. The result is not conclusive yet.

Obstacle: 6:08

cyndichiang

Speaker
Some people think that a small amount of alcohol is beneficial to heart.
However,new study shows that ahcohol benefits only certain people with specific gene
Experiment: 600 people with heart disease and 3000 healthy volunteer
Researchers compare their gene which control transportation of alcogol and outcome is that overall 20% reduction of heart disease risk occurs, 80% from those people with certain gene.
Only 50% people have this lucky gene and the rest of us get no benefits from alcohol at all

Obstacle 6'49''
Effects of hangover.  acetaldehyde(ADH) acetate(ALDH)-->symptons
Possible explanations of the reasons for this suffer-->the role of acetaldehyde
-->e.g Japan 's experiment: fallacy:participants with the enzyme mutation
--->e.g.another experiment: congeners
Cures of hangover:
beverages' effects-->4 beverage can  increased ADH and ALDH activity
antidotes

seraph797979

Going 发表于 2014-11-18 21:04
Part II: Speed

2,2'09
3,2'23
4,1'29
5,2'40
6,1'25

Phoebedyf2

time2: 02'37''
the alcohol content of wine has increased. scientist decided to decrease the sugar in grape during the fermentation.
a new yeast can reduce the alcohol content. People like it.
However, more sugar, more alcohol.

time3: 03'27''
Stamp and a man think wines should not be treated as bad things, there are too much concentrations.

time4: 02'00''
Finding ways to keep fruit flavor while reducing alcohol is a challenge, and scientists tried to find a new wild yeast.

time5: 03'51''
Scientist found a wild yeast that can reduce the alcohol and meawhile, add different flavor to the wine.

time6: 01'43''
Developing a new wild yeast is unfinished. A test for tasting has made.  Maybe a new yeast of M can reduce alcohol.

obstacel: 13'41''......