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A new twist on prion disease
In 1997 Stanley Pruisner was awarded the Nobel Prize for physiology or medicine for his theory that a deviant form of a harmless protein could be an infectious agent, a transmitter of disease. Named prions (short for proteinaceous infectious particle) these misshapen proteins cause healthy proteins to misfold, fatally clumping together in the brain. Unlike other disease-causing agents where replicating molecule is presumed to be composed of nucleic acid, prions lack genetic material (DNA and RNA). Neurodegenerative prion diseases are often called spongiform encephalopathies because they leave the brain riddled with holes like a sponge. In animals, prion diseases include scrapie in sheep and bovine spongiform encephalopathy, commonly known as mad cow disease in cattle. In humans, diseases such as kuru and Creutzfeldt-Jakob disease (CJD) are also thought to be caused by prions. All the diseases are characterized by loss of motor control, dementia, paralysis, and ensuing death due to massive destruction of brain tissue.
Humans are thought to contract prion disease most commonly by eating prion-contaminated flesh. Kuru, a rare and fatal brain disorder, brought prion disease to the forefront. First described in the 1950s, kuru was most common among the Fore people of Papua New Guinea, who had a custom of eating the brains of their dead during funeral feasts. It is speculated that a tribe member developed CJD, his or her contaminated brain tissue was ingested, and the disease spread. Kuru reached epidemic levels in the 1960s, but the disease declined after the government discouraged the practice of cannibalism and now it has almost completely disappeared.
Inherited prion diseases are rare and passed through families. But it’s long been a puzzle why prions attack neurons more than other types of cells, and how they do their damage. In a new study, researchers propose that prions deplete a poorly understood protein that normally keeps nerve cells healthy. The theory still has a ways to go before it’s proven, but researchers are intrigued by this potential new twist on a mysterious disease.
The normal prion protein gene (PRNP) provides instructions for making a protein called the prion protein (PrP), which is active in the brain and several other tissues. Yet researchers don’t know exactly why but when prion misfolds, the results are disastrous.
Jennifer Couzin-Frankel. Science NOW. In: Daily News (adapted).
In relation to the text above, judge the item.
Mutations in the PRNP gene cause prion disease.
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A new twist on prion disease
In 1997 Stanley Pruisner was awarded the Nobel Prize for physiology or medicine for his theory that a deviant form of a harmless protein could be an infectious agent, a transmitter of disease. Named prions (short for proteinaceous infectious particle) these misshapen proteins cause healthy proteins to misfold, fatally clumping together in the brain. Unlike other disease-causing agents where replicating molecule is presumed to be composed of nucleic acid, prions lack genetic material (DNA and RNA). Neurodegenerative prion diseases are often called spongiform encephalopathies because they leave the brain riddled with holes like a sponge. In animals, prion diseases include scrapie in sheep and bovine spongiform encephalopathy, commonly known as mad cow disease in cattle. In humans, diseases such as kuru and Creutzfeldt-Jakob disease (CJD) are also thought to be caused by prions. All the diseases are characterized by loss of motor control, dementia, paralysis, and ensuing death due to massive destruction of brain tissue.
Humans are thought to contract prion disease most commonly by eating prion-contaminated flesh. Kuru, a rare and fatal brain disorder, brought prion disease to the forefront. First described in the 1950s, kuru was most common among the Fore people of Papua New Guinea, who had a custom of eating the brains of their dead during funeral feasts. It is speculated that a tribe member developed CJD, his or her contaminated brain tissue was ingested, and the disease spread. Kuru reached epidemic levels in the 1960s, but the disease declined after the government discouraged the practice of cannibalism and now it has almost completely disappeared.
Inherited prion diseases are rare and passed through families. But it’s long been a puzzle why prions attack neurons more than other types of cells, and how they do their damage. In a new study, researchers propose that prions deplete a poorly understood protein that normally keeps nerve cells healthy. The theory still has a ways to go before it’s proven, but researchers are intrigued by this potential new twist on a mysterious disease.
The normal prion protein gene (PRNP) provides instructions for making a protein called the prion protein (PrP), which is active in the brain and several other tissues. Yet researchers don’t know exactly why but when prion misfolds, the results are disastrous.
Jennifer Couzin-Frankel. Science NOW. In: Daily News (adapted).
In relation to the text above, judge the item.
The lack of healthy cells creates crevices inside the brain that produce the mental and behaviourial features of prior diseases.
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A new twist on prion disease
In 1997 Stanley Pruisner was awarded the Nobel Prize for physiology or medicine for his theory that a deviant form of a harmless protein could be an infectious agent, a transmitter of disease. Named prions (short for proteinaceous infectious particle) these misshapen proteins cause healthy proteins to misfold, fatally clumping together in the brain. Unlike other disease-causing agents where replicating molecule is presumed to be composed of nucleic acid, prions lack genetic material (DNA and RNA). Neurodegenerative prion diseases are often called spongiform encephalopathies because they leave the brain riddled with holes like a sponge. In animals, prion diseases include scrapie in sheep and bovine spongiform encephalopathy, commonly known as mad cow disease in cattle. In humans, diseases such as kuru and Creutzfeldt-Jakob disease (CJD) are also thought to be caused by prions. All the diseases are characterized by loss of motor control, dementia, paralysis, and ensuing death due to massive destruction of brain tissue.
Humans are thought to contract prion disease most commonly by eating prion-contaminated flesh. Kuru, a rare and fatal brain disorder, brought prion disease to the forefront. First described in the 1950s, kuru was most common among the Fore people of Papua New Guinea, who had a custom of eating the brains of their dead during funeral feasts. It is speculated that a tribe member developed CJD, his or her contaminated brain tissue was ingested, and the disease spread. Kuru reached epidemic levels in the 1960s, but the disease declined after the government discouraged the practice of cannibalism and now it has almost completely disappeared.
Inherited prion diseases are rare and passed through families. But it’s long been a puzzle why prions attack neurons more than other types of cells, and how they do their damage. In a new study, researchers propose that prions deplete a poorly understood protein that normally keeps nerve cells healthy. The theory still has a ways to go before it’s proven, but researchers are intrigued by this potential new twist on a mysterious disease.
The normal prion protein gene (PRNP) provides instructions for making a protein called the prion protein (PrP), which is active in the brain and several other tissues. Yet researchers don’t know exactly why but when prion misfolds, the results are disastrous.
Jennifer Couzin-Frankel. Science NOW. In: Daily News (adapted).
In relation to the text above, judge the item.
The abnormal protein builds up in the brain, forming clumps that damage or annihilate neurons.
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Questão presente nas seguintes provas
A new twist on prion disease
In 1997 Stanley Pruisner was awarded the Nobel Prize for physiology or medicine for his theory that a deviant form of a harmless protein could be an infectious agent, a transmitter of disease. Named prions (short for proteinaceous infectious particle) these misshapen proteins cause healthy proteins to misfold, fatally clumping together in the brain. Unlike other disease-causing agents where replicating molecule is presumed to be composed of nucleic acid, prions lack genetic material (DNA and RNA). Neurodegenerative prion diseases are often called spongiform encephalopathies because they leave the brain riddled with holes like a sponge. In animals, prion diseases include scrapie in sheep and bovine spongiform encephalopathy, commonly known as mad cow disease in cattle. In humans, diseases such as kuru and Creutzfeldt-Jakob disease (CJD) are also thought to be caused by prions. All the diseases are characterized by loss of motor control, dementia, paralysis, and ensuing death due to massive destruction of brain tissue.
Humans are thought to contract prion disease most commonly by eating prion-contaminated flesh. Kuru, a rare and fatal brain disorder, brought prion disease to the forefront. First described in the 1950s, kuru was most common among the Fore people of Papua New Guinea, who had a custom of eating the brains of their dead during funeral feasts. It is speculated that a tribe member developed CJD, his or her contaminated brain tissue was ingested, and the disease spread. Kuru reached epidemic levels in the 1960s, but the disease declined after the government discouraged the practice of cannibalism and now it has almost completely disappeared.
Inherited prion diseases are rare and passed through families. But it’s long been a puzzle why prions attack neurons more than other types of cells, and how they do their damage. In a new study, researchers propose that prions deplete a poorly understood protein that normally keeps nerve cells healthy. The theory still has a ways to go before it’s proven, but researchers are intrigued by this potential new twist on a mysterious disease.
The normal prion protein gene (PRNP) provides instructions for making a protein called the prion protein (PrP), which is active in the brain and several other tissues. Yet researchers don’t know exactly why but when prion misfolds, the results are disastrous.
Jennifer Couzin-Frankel. Science NOW. In: Daily News (adapted).
In relation to the text above, judge the item.
In mad cow disease, misfolded proteins prions punch holes in the brain causing the tissue to develop a spongy architecture eventually destroying it.
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Questão presente nas seguintes provas
Um estudo sobre a duração de uma operação de carregamento mostrou haver relação linear na forma!$ Y_k=\beta X_k + \epsilon_k !$ ,em que Yk é o tempo (horas) do carregamento k; Xk é o volume total (em toneladas) do carregamento k; !$ \beta !$ é o coeficiente angular; e !$ \epsilon_k !$ representa um erro aleatório com média zero e variância !$ \sigma^2 !$.
De uma amostra aleatória de 341 operações de carregamento, observam-se os seguintes resultados: !$ \sum_{K-1}^ {341} X_kY_k=988 !$; !$ \sum_{K-1} ^ {341} X^2_k=1.704 !$; !$ \sum_{K-1} ^ {341} X_k =682 !$; !$ \sum_{K-1} ^ {341} Y^2_k =681 !$; !$ \sum_{K-1} ^ {341} Y_k =341 !$.
Com base nessas informações, julgue o item a seguir.
O erro padrão do estimador de mínimos quadrados de !$ \beta !$ é inferior a 0,01.
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Questão presente nas seguintes provas
Um estudo sobre a duração de uma operação de carregamento mostrou haver relação linear na forma
!$ Y_k=\beta X_k + \epsilon_k !$ ,
em que Yk é o tempo (horas) do carregamento k; Xk é o volume total (em toneladas) do carregamento k; !$ \beta !$ é o coeficiente angular; e !$ \epsilon_k !$ representa um erro aleatório com média zero e variância !$ \sigma^2 !$.
De uma amostra aleatória de 341 operações de carregamento, observam-se os seguintes resultados:
!$ \sum_{k=1}^ {341} X_kY_k=988 !$;
!$ \sum_{k=1} ^ {341} X^2_k=1.704 !$;
!$ \sum_{k=1} ^ {341} X_k =682 !$;
!$ \sum_{k=1} ^ {341} Y^2_k =681 !$;
!$ \sum_{k=1} ^ {341} Y_k =341 !$.
Com base nessas informações, julgue o item a seguir.
Com base nessas informações, julgue o item a seguir.
Sendo !$ \overline{y} !$,!$ \overline{x} !$ e !$ \mathrm{\beta} !$,respectivamente, a média dos tempos de carregamento, a média dos volumes totais do carregamento e a estimativa de mínimos quadrados do coeficiente angular do modelo, então !$ \overline{y}=\beta\overline{x} !$.
Provas
Questão presente nas seguintes provas
Nature Inc.
Return of the groundbreaking series that puts a price-tag on environmental services.
The series kicks off with Natural Prevention, a reckoning of how an investment in natural barriers such as marshes and mangroves to tsunamis and hurricanes can save billions of dollars as well as thousands of lives. “Nature has spent billions of years developing how to do the most with the least”, comments one scientist in the programme.
The last programme in the six part series — Now and Forever — looks ahead to Copenhagen and the major climate conference convened to replace the Kyoto agreement.
“We feature the scary number crunching of former World Bank chief economist, Nicholas Stern, who has worked out that climate change, if it’s business as usual, could by 2100 cost up to 20% of World GDP. Taking action by contrast, would cost just 2%”, says programme producer, Ken Pugh.
Already according to the assessment of a new UN study set to report in 2010, the International Year of Biodiversity, we are losing over US$ 4 trillion in so-called ecosystem services every year.
Interviewed by Nature Inc., the UN study leader and a former Deutsche Bank manager, Pavan Sukhdev, says: “These sums are staggering and represent the real credit crunch.”
Interviewed at the World Conservation Union headquarters in Switzerland, IUCN director general Julia Marton- Lefevre also tells Nature Inc.: “We have seen around the world the credit crunch is very real — but for a long time now there has also been a nature crunch going on — and it’s far bigger, but the world hasn’t realized it yet.”
Nature Inc. also spends a day in Washington DC with UNEP executive director, Achim Steiner, as he finds support from an unexpected quarter — the American trade unions that have begun to accept that investments in energy efficiency can help safeguard jobs.
Achim Steiner, tells Nature Inc.: “I believe the green economy is already happening all over the planet.”
“In all the programmes, Nature Inc. addresses the conundrum that while everyone accepts that conservation has an economic value, the unregulated free market cannot really fix a workable monetary value on ecosystem services,” says series editor Robert Lamb, a veteran of environmental programming for 25 years.
“But what is interesting is that the green calculations of wealth that 10 years ago would have been dismissed out of hand by most establishment economists are now widely accepted.”
“The root of the word ‘economy’ is ‘ecology’, perhaps it’s all turning full circle?”
“The ‘triple crunch’ of climate, credit, and energy insecurity, is forcing governments to seriously consider the “green economy” as a way of making a sustainable recovery.
The recent London G20 Summit emphasized that investment in environmentally sound technology and business could also create sustainable jobs.
Nature Inc. goes to China, India, USA, Spain, Bangladesh and Colombia to examine the claim that green investment equals green jobs.
BBC World News (adapted).
Acording to the ideas expressed in the text above, judge the following item.
While it is conceivable to place an accurate monetary amount on ecosystem services, it stimulates market-based conservation and financial values.
Provas
Questão presente nas seguintes provas
Nature Inc.
Return of the groundbreaking series that puts a price-tag on environmental services.
The series kicks off with Natural Prevention, a reckoning of how an investment in natural barriers such as marshes and mangroves to tsunamis and hurricanes can save billions of dollars as well as thousands of lives. “Nature has spent billions of years developing how to do the most with the least”, comments one scientist in the programme.
The last programme in the six part series — Now and Forever — looks ahead to Copenhagen and the major climate conference convened to replace the Kyoto agreement.
“We feature the scary number crunching of former World Bank chief economist, Nicholas Stern, who has worked out that climate change, if it’s business as usual, could by 2100 cost up to 20% of World GDP. Taking action by contrast, would cost just 2%”, says programme producer, Ken Pugh.
Already according to the assessment of a new UN study set to report in 2010, the International Year of Biodiversity, we are losing over US$ 4 trillion in so-called ecosystem services every year.
Interviewed by Nature Inc., the UN study leader and a former Deutsche Bank manager, Pavan Sukhdev, says: “These sums are staggering and represent the real credit crunch.”
Interviewed at the World Conservation Union headquarters in Switzerland, IUCN director general Julia Marton- Lefevre also tells Nature Inc.: “We have seen around the world the credit crunch is very real — but for a long time now there has also been a nature crunch going on — and it’s far bigger, but the world hasn’t realized it yet.”
Nature Inc. also spends a day in Washington DC with UNEP executive director, Achim Steiner, as he finds support from an unexpected quarter — the American trade unions that have begun to accept that investments in energy efficiency can help safeguard jobs.
Achim Steiner, tells Nature Inc.: “I believe the green economy is already happening all over the planet.”
“In all the programmes, Nature Inc. addresses the conundrum that while everyone accepts that conservation has an economic value, the unregulated free market cannot really fix a workable monetary value on ecosystem services,” says series editor Robert Lamb, a veteran of environmental programming for 25 years.
“But what is interesting is that the green calculations of wealth that 10 years ago would have been dismissed out of hand by most establishment economists are now widely accepted.”
“The root of the word ‘economy’ is ‘ecology’, perhaps it’s all turning full circle?”
“The ‘triple crunch’ of climate, credit, and energy insecurity, is forcing governments to seriously consider the “green economy” as a way of making a sustainable recovery.
The recent London G20 Summit emphasized that investment in environmentally sound technology and business could also create sustainable jobs.
Nature Inc. goes to China, India, USA, Spain, Bangladesh and Colombia to examine the claim that green investment equals green jobs.
BBC World News (adapted).
Acording to the ideas expressed in the text above, judge the following item.
Next century climate change recovery will assuredly mount up ten times withal of the World GDP.
Provas
Questão presente nas seguintes provas
Nature Inc.
Return of the groundbreaking series that puts a price-tag on environmental services.
The series kicks off with Natural Prevention, a reckoning of how an investment in natural barriers such as marshes and mangroves to tsunamis and hurricanes can save billions of dollars as well as thousands of lives. “Nature has spent billions of years developing how to do the most with the least”, comments one scientist in the programme.
The last programme in the six part series — Now and Forever — looks ahead to Copenhagen and the major climate conference convened to replace the Kyoto agreement.
“We feature the scary number crunching of former World Bank chief economist, Nicholas Stern, who has worked out that climate change, if it’s business as usual, could by 2100 cost up to 20% of World GDP. Taking action by contrast, would cost just 2%”, says programme producer, Ken Pugh.
Already according to the assessment of a new UN study set to report in 2010, the International Year of Biodiversity, we are losing over US$ 4 trillion in so-called ecosystem services every year.
Interviewed by Nature Inc., the UN study leader and a former Deutsche Bank manager, Pavan Sukhdev, says: “These sums are staggering and represent the real credit crunch.”
Interviewed at the World Conservation Union headquarters in Switzerland, IUCN director general Julia Marton- Lefevre also tells Nature Inc.: “We have seen around the world the credit crunch is very real — but for a long time now there has also been a nature crunch going on — and it’s far bigger, but the world hasn’t realized it yet.”
Nature Inc. also spends a day in Washington DC with UNEP executive director, Achim Steiner, as he finds support from an unexpected quarter — the American trade unions that have begun to accept that investments in energy efficiency can help safeguard jobs.
Achim Steiner, tells Nature Inc.: “I believe the green economy is already happening all over the planet.”
“In all the programmes, Nature Inc. addresses the conundrum that while everyone accepts that conservation has an economic value, the unregulated free market cannot really fix a workable monetary value on ecosystem services,” says series editor Robert Lamb, a veteran of environmental programming for 25 years.
“But what is interesting is that the green calculations of wealth that 10 years ago would have been dismissed out of hand by most establishment economists are now widely accepted.”
“The root of the word ‘economy’ is ‘ecology’, perhaps it’s all turning full circle?”
“The ‘triple crunch’ of climate, credit, and energy insecurity, is forcing governments to seriously consider the “green economy” as a way of making a sustainable recovery.
The recent London G20 Summit emphasized that investment in environmentally sound technology and business could also create sustainable jobs.
Nature Inc. goes to China, India, USA, Spain, Bangladesh and Colombia to examine the claim that green investment equals green jobs.
BBC World News (adapted).
Acording to the ideas expressed in the text above, judge the following item.
Nature Inc. may be a system overhaul to establish monetary value on ecosystem services.
Provas
Questão presente nas seguintes provas
Nature Inc.
Return of the groundbreaking series that puts a price-tag on environmental services.
The series kicks off with Natural Prevention, a reckoning of how an investment in natural barriers such as marshes and mangroves to tsunamis and hurricanes can save billions of dollars as well as thousands of lives. “Nature has spent billions of years developing how to do the most with the least”, comments one scientist in the programme.
The last programme in the six part series — Now and Forever — looks ahead to Copenhagen and the major climate conference convened to replace the Kyoto agreement.
“We feature the scary number crunching of former World Bank chief economist, Nicholas Stern, who has worked out that climate change, if it’s business as usual, could by 2100 cost up to 20% of World GDP. Taking action by contrast, would cost just 2%”, says programme producer, Ken Pugh.
Already according to the assessment of a new UN study set to report in 2010, the International Year of Biodiversity, we are losing over US$ 4 trillion in so-called ecosystem services every year.
Interviewed by Nature Inc., the UN study leader and a former Deutsche Bank manager, Pavan Sukhdev, says: “These sums are staggering and represent the real credit crunch.”
Interviewed at the World Conservation Union headquarters in Switzerland, IUCN director general Julia Marton- Lefevre also tells Nature Inc.: “We have seen around the world the credit crunch is very real — but for a long time now there has also been a nature crunch going on — and it’s far bigger, but the world hasn’t realized it yet.”
Nature Inc. also spends a day in Washington DC with UNEP executive director, Achim Steiner, as he finds support from an unexpected quarter — the American trade unions that have begun to accept that investments in energy efficiency can help safeguard jobs.
Achim Steiner, tells Nature Inc.: “I believe the green economy is already happening all over the planet.”
“In all the programmes, Nature Inc. addresses the conundrum that while everyone accepts that conservation has an economic value, the unregulated free market cannot really fix a workable monetary value on ecosystem services,” says series editor Robert Lamb, a veteran of environmental programming for 25 years.
“But what is interesting is that the green calculations of wealth that 10 years ago would have been dismissed out of hand by most establishment economists are now widely accepted.”
“The root of the word ‘economy’ is ‘ecology’, perhaps it’s all turning full circle?”
“The ‘triple crunch’ of climate, credit, and energy insecurity, is forcing governments to seriously consider the “green economy” as a way of making a sustainable recovery.
The recent London G20 Summit emphasized that investment in environmentally sound technology and business could also create sustainable jobs.
Nature Inc. goes to China, India, USA, Spain, Bangladesh and Colombia to examine the claim that green investment equals green jobs.
BBC World News (adapted).
Acording to the ideas expressed in the text above, judge the following item.
An ecological approach to economy will transform the whole system of capitalist production.
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