For several species mortality increases with age — as expected by evolutionary scientists. This pattern is seen in most mammal species including humans and killer whales, but also in invertebrates like water fleas. However, other species experience a decrease in mortality as they age, and in some cases mortality drops all the way up to death. This applies to species like the desert tortoise (Gopherus agassizii) which experiences the highest mortality early on in life and a steadily declining mortality as it ages. Many plant species, e.g. the white mangrove tree (Avicennia marina) follow the same pattern.
Amazingly, there are also species that have constant mortality and remain unaffected by the aging process. This is most striking in the freshwater polyp Hydra magnipapillata which has constant low mortality. In fact, in lab conditions, it has such a low risk of dying at any time in its life that it is effectively immortal.
\”Extrapolation from laboratory data show that even after 1400 years five per cent of a hydra population kept in these conditions would still be alive,\” says Owen Jones.
Several animal and plant species show remarkably little change in mortality throughout their life course. For example, these include rhododendron (Rhododendron maximum), great tit (Parus major), hermit crab (Pagurus longicarpus), common lizard (Lacerta vivapara), collared flycatcher (Ficedula albicollis), viburnum plants (Viburnum furcatum ), oarweed (Laminaria digitata), red abalone (Haliotis rufescens), the plant armed saltbush (Atriplex acanthocarpa), red-legged frog (Rana aurora) and the coral red gorgonian (Paramuricea clavata).
When you look at the fertility patterns of the 46 surveyed species, there is also a great diversity and some large departures from the common beliefs about aging. Human fertility is characterized by being concentrated in a relatively short period of life, and by the fact that humans live for a rather long time both before and after the fertile period.
A similar pattern of a concentrated fertile period is also seen in other mammals like killer whales, chimpanzees, and chamois (Rupicapra rupicapra), and also in birds like sparrow hawks (Accipiter nisus).
However, there are also species that become more and more fertile with age, and this pattern is especially common in plants such as the agave (Agave marmorata) and the rare mountain plants hypericum (Hypericum cumulicola) and borderea (Borderea pyrenaica).
On the contrary fertility occurs very early in the nematode worm Caenorhabditis elegans. Actually this species starts its life with being fertile, then it quite quickly and quite suddenly loses the ability to produce offspring.
To sum up there is no strong correlation between the patterns of aging and the typical life spans of the species. Species can have increasing mortality and still live a long time, or have declining mortality and still live a short time.
“It makes no sense to consider aging to be based on how old a species can become. Instead, it is more interesting to define aging as being based on the shape of mortality trajectories: whether rates increase, decrease or remain constant with age,” says Owen Jones.
If scientists are correct, jellyfish may hold the key to immortality.
That’s the premise of a New York Times Magazine article that examines a species of jellyfish (appropriately) nicknamed the “immortal jellyfish.”
Known officially as Turritopsis nutricula (and sometimes as Turritopsis dohrnii), the minute creature has the ability to transform its cells back into a youthful state. As National Geographic puts it, the jellyfish transforms “into a blob-like cyst” that grows into a polyp colony — the first stage of life.
From there, the jellyfish continues a conventional lifecycle, maturing and mating. Instead of dying, however, the immortal jelly reverts, time and again, back into the polyp colony. That ability “allows the jellyfish to bypass death, rendering [it] biologically immortal,” notes Hongbao Ma, a researcher at Brookdale University Hospital and Medical Center in Brooklyn, N.Y.
According to a study published in “Nature and Science,”the jellyfish accomplishes this unique feat via “transdifferentiation.” Essentially, the creature absorbs its cells, then transforms them into cells of any other type.
With life skills this advanced, it’s no surprise the jellyfish has populated the globe in what’s been termed “a worldwide silent invasion,” the Telegraph notes. ..
Archive for the ‘Survival’ Category
Posted by Xeno on December 9, 2013
Posted by Xeno on December 9, 2013
Massive reserves of “freshwater” are buried beneath the seabed on continental shelves around the world, including off Australia, China, North America and South Africa.This is the conclusion of a new study by a team of Australian scientists that appears in this week’s issue of the journal, Nature.Based on an analysis of seafloor water studies conducted for oil and gas exploration purposes, the study showed that an estimated that 500,000 cubic kilometers of low-salinity water is trapped in aquifers under the ocean floor.“The volume of this water resource is a hundred times greater than the amount we’ve extracted from the Earth’s sub-surface in the past century since 1900,” said Vincent Post, a groundwater hydro geologist from Flinders University in Adelaide and the new study’s lead author.This new freshwater resource could give regions suffering with limited access to freshwater more options for combating the impact of droughts and alleviating the impact of water scarcity on future generations.By 2030, nearly 50% of the planet’s population will exist under
conditions of high water stress, according to the United Nations.The new study undercuts the conventional wisdom on undersea freshwater reserves, which until now were considered to be rare.“By combining all this information we’ve demonstrated that the freshwater below the seafloor is a common finding, and not some anomaly that only occurs under very special circumstances,” said Post.
“The volume of this water resource is a hundred times greater than the amount we’ve extracted from the Earth’s sub-surface in the past century since 1900,” Post said in a statement. “Knowing about these reserves is great news because this volume of water could sustain some regions for decades.”
While he said that groundwater scientists were aware that there was freshwater located beneath the ocean seafloor, they believed that it only happened in a handful of places and only under special conditions. However, their new research has revealed that these types of aquifers “are actually quite a common phenomenon.”
According to Forbes contributor William Pentland, the United Nations warns that nearly half of the global population will live under
conditions of high water stress by the year 2030. Post’s team’s findings could help delay that looming water crisis, while also providing potential relief for drought-stricken regions.
The discovery was the result of a review of seafloor water studies conducted for scientific or petroleum exploration purposes, Post told AFP. The newly-discovered freshwater deposits were reportedly formed over hundreds of thousands of years, during a time where lower sea levels meant that the regions that are now under the ocean had been exposed to precipitation. That rain would have been absorbed into the underlying water table.
“Freshwater under the seabed is much less salty than seawater,” he said. “This means it can be converted to drinking water with less energy than seawater desalination, and it would also leave us with a lot less hyper-saline water.”
“Freshwater on our planet is increasingly under stress and strain so the discovery of significant new stores off the coast is very exciting. It means that more options can be considered to help reduce the impact of droughts and continental water shortages,” Post continued, adding that it was now important to care for the seabed. “For example, where low-salinity groundwater below the sea is likely to exist, we should take care to not contaminate it.” …
Is fresh water still the new oil?
Posted by Xeno on October 31, 2013
One of the obstacles to employing human embryonic stem cells for medical use lies in their very promise: They are born to rapidly differentiate into other cell types. Until now, scientists have not been able to efficiently keep embryonic stem cells in their pristine stem state. The alternative that has been proposed to embryonic stem cells – reprogrammed adult cells called induced pluripotent stem cells (iPS cells) – have similar limitations. Though these can differentiate into many different cell types, they retain signs of “priming,” – commitment to specific cell lineages.
A team at the Weizmann Institute of Science has now taken a large step toward removing that obstacle: They have created iPS cells that are completely “reset” to the earliest possible state and maintained them in that state. Among other things, this research may, in the future, pave the way toward the ability to grow transplant organs to order.
Since they were first created in 2006, iPS cells have been touted as an ethical and practical substitute for embryonicstem cells. They are made by inserting four genes into the genomes of suchadult cells as skin cells. This turns back the developmental clock almost all the way – but not completely – to an embryonic-stem-cell-like state. Dr. Jacob Hanna of the Institute’s Molecular Genetics Department and his team, including research students Ohad Gafni and Leehee Weinberger and researchers in the Israel National Center for Personalized Medicine, realized that inserting genes to reset the stem cells was not enough. One also has to put the cells’ drive to differentiate on hold.
Posted by Xeno on October 30, 2013
The UN voted last week to adopt a proposal from the Association of Space Explorers (ASE) to form an “International Asteroid Warning Group” to defend the planet from asteroids, Scientific American first reported. Member states will use the group to share information on Near Earth Objects (NEOs) and pull together a response to a hypothetical asteroid strike.
The news comes about a week after NASA reported that asteroid 2013 TV135 had skimmed within 4.2 million miles of Earth back in September and is due to return to Earth’s neighborhood in 2032. Should it hit Earth, the explosion would be equivalent to a 2,500 megaton bomb, NASA said – that’s about 125,000 times the size of the bomb dropped on Nagasaki, the Christian Science Monitor reported.
Though NASA has said that odds that the asteroid will impact Earth is just one in 63,000, there’s no getting around the fact that, at the moment, Earth has no control over those odds, the ASE notes. For all the alarm about the rocks hurtling through the solar system, Earth does not have an international defense plan against these threats of impending doom.
Sure, individual states have been gearing up to tackle asteroids on their own. Since April, NASA has been pursuing its so-called Asteroid Redirect Mission, a proposal that includes snagging an asteroid and then sending a manned spacecraft to sample it, all between the years 2018 and 2021. A month later, the European Space Agency (ESA) opened its own office charged with detecting dangerous NEOs.
But, at the moment, there is no international plan for who, or when, or how Earth would respond an asteroid. So, in order to avoid a political tussle over obligations and responsibilities as an asteroid hurtles toward humanity’s home, the ASE is asking the UN to sort it out sooner rather than later.
“Now that humankind has the scientific, technical and operational capabilities both to predict whether an asteroid will come too close for comfort, and to launch operational missions to deflect a potential impact, it is time for the international community to identify the decision-making institutions and begin the development of a coordinated decision-making process,” writes the ASE, in their report.
“In the absence of an agreed-upon decision-making process, we may lose the opportunity to act against a NEO in time, leaving evacuation and disaster management as our only response to a pending impact,” the authors write.
The adopted proposal suggests a two-pronged approach to defending the Earth from asteroids. First, the UN must coordinate efforts to better catalogue just what threats are out there, said Ed Lu, a former NASA astronaut and co-founder of the B612 Foundation, at a talk given this week at the American Museum of Natural History, in New York City.
As of Oct. 14, NASA has recorded the existence of 10,332 Near-Earth objects. But the number of asteroids near Earth is estimated to be a hundred times that, said Mr. Lu. When a meteor exploded above Siberia earlier this year, NASA’s telescopes had not even seen it coming. The explosion injured 1,500 people.
“You cannot deflect an asteroid that we haven’t yet found,” said Lu.
Unless an errant asteroid is detected at least a year out from the date of its expected impact from Earth, there is little that Earthlings can do about it expect fix themselves “a nice cocktail and go out and watch,” said Rusty Schweickart, a former astronaut and a member of the ASE, at the same talk.
The report’s authors also envision the new committee as a forum through which countries can organize a test mission to fend off a problematic asteroid.
“Faced with such a threat, we are far from helpless,” write the authors, in the report.
“For the first time in our planet’s 4.5-billion-year history, the technical capacities exist to prevent such cosmic collisions with Earth. The keys to a successful outcome in all cases are preparation, planning, and timely decision-making,” the authors say. …
Posted by Xeno on October 25, 2013
Hayashi, 41, says he was recruited for a job monitoring the radiation exposure of workers leaving the plant in the summer of 2012. Instead, when he turned up for work, he was handed off through a web of contractors and assigned, to his surprise, to one of Fukushima’s hottest radiation zones.
He was told he would have to wear an oxygen tank and a double-layer protective suit. Even then, his handlers told him, the radiation would be so high it could burn through his annual exposure limit in just under an hour.
“I felt cheated and entrapped,” Hayashi said. “I had not agreed to any of this.”
When Hayashi took his grievances to a firm on the next rung up the ladder of Fukushima contractors, he says he was fired. He filed a complaint but has not received any response from labor regulators for more than a year. All the eight companies involved, including embattled plant operator Tokyo Electric Power Co, declined to comment or could not be reached for comment on his case.
Out of work, Hayashi found a second job at Fukushima, this time building a concrete base for tanks to hold spent fuel rods. His new employer skimmed almost a third of his wages – about $1,500 a month – and paid him the rest in cash in brown paper envelopes, he says. Reuters reviewed documents related to Hayashi’s complaint, including pay envelopes and bank statements.
Hayashi’s hard times are not unusual in the estimated $150-billion effort to dismantle the Fukushima reactors and clean up the neighboring areas, a Reuters examination found.
In reviewing Fukushima working conditions, Reuters interviewed more than 80 workers, employers and officials involved in the unprecedented nuclear clean-up. A common complaint: the project’s dependence on a sprawling and little scrutinized network of subcontractors – many of them inexperienced with nuclear work and some of them, police say, have ties to organized crime.
Tepco sits atop a pyramid of subcontractors that can run to seven or more layers and includes construction giants such as Kajima Corp and Obayashi Corp in the first tier. The embattled utility remains in charge of the work to dismantle the damaged Fukushima reactors, a government-subsidized job expected to take 30 years or more.
Outside the plant, Japan’s “Big Four” construction companies – Kajima, Obayashi, Shimizu Corp and Taisei Corp – oversee hundreds of small firms working on government-funded contracts to remove radioactive dirt and debris from nearby villages and farms so evacuees can return home.
Tokyo Electric, widely known as Tepco, says it has been unable to monitor subcontractors fully but has taken steps to limit worker abuses and curb the involvement of organized crime.
“We sign contracts with companies based on the cost needed to carry out a task,” Masayuki Ono, a general manager for nuclear power at Tepco, told Reuters. “The companies then hire their own employees taking into account our contract. It’s very difficult for us to go in and check their contracts.”
The unprecedented Fukushima nuclear clean-up both inside and outside the plant faces a deepening shortage of workers. There are about 25 percent more openings than applicants for jobs in Fukushima prefecture, according to government data.
Raising wages could draw more workers but that has not happened, the data shows. Tepco is under pressure to post a profit in the year to March 2014 under a turnaround plan Japan’s top banks recently financed with $5.9 billion in new loans and refinancing. In 2011, in the wake of the disaster, Tepco cut pay for its own workers by 20 percent.
With wages flat and workers scarce, labor brokers have stepped into the gap, recruiting people whose lives have reached a dead end or who have trouble finding a job outside the disaster zone.
The result has been a proliferation of small firms – many unregistered. Some 800 companies are active inside the Fukushima plant and hundreds more are working in the decontamination effort outside its gates, according to Tepco and documents reviewed by Reuters. …
Posted by Xeno on October 21, 2013
A 72-year-old California deer hunter was recovering Monday after surviving on squirrels and packing leaves around him for warmth for nearly three weeks while he was lost and alone in the snowy wilderness, authorities said.
Gene Penaflor was discovered by hunters on Saturday after 19 days in the Mendocino National Forest in the Coastal Mountain Range of northwestern California, according to a report by the Mendocino County Sheriff’s Office.
“This is a miracle,” reads a message on a website dedicated to the search, www.genepenaflor.com, updated with a family photo at a local hospital over the weekend.
The Mendocino National Forest is run by the U.S. Forest Service and has been closed due to the government shutdown, according to the forest website. An outgoing voicemail message by a forest spokesperson said she had been furloughed.
Penaflor, described on the site as an avid hunter with more than 30 years of wilderness experience, had been hunting with a friend when they became separated on Sept. 24, the report said.
After four days of searching by at least 18 agencies from more than a dozen counties, the official search was suspended because searchers could find no clues to his locations and because storms were coming.
On Saturday, 19 days after Penaflor disappeared, the search was resumed – but it was a group of hunters who heard Penaflor’s cries for help and eventually found him in a canyon in the 53,887-acre Yuki Wilderness area of the national forest.
He told officials he had walked too far away from the road, fell and hit his head, and was knocked unconscious. When he regained consciousness he was disoriented, surrounded by thick fog in a forest where the temperature dipped to 25 degrees.
“He was able to make a fire and warm himself with leaves and grasses that he packed around his body,” the report said. “On days when it rained or snowed he was able to crawl under a large log to stay dry. He was able to kill and eat several squirrels in the area and there was plenty of water in a nearby drainage to sustain himself.”
Penaflor is recovering well, according to social media postings by his son, Jeremy Penaflor. …
Good job, Gene. A younger less experienced person may not have done as well.
Posted by Xeno on October 21, 2013
Scientists have devised a biological clock using DNA and hope to use it to slow ageing and fight cancer.
The clock compares the biological “age” of body tissue to a person’s age in years.
The clock was found embedded in genomes, which is the complete genetic make up of a person, and could help scientists discover why humans age and how to slow the process.
It was discovered that healthy female breast tissue was two to three years older than other tissue in the body.
However tissue next to tumours was 12 years older and the tumour tissue itself was 36 years older.
This could explain why breast cancer is the most common cancer in women and why age is a major risk factor for many cancers in both genders.
Results showed while most people’s biological age matched their true age, others differed significantly.
Professor Steve Horvath, of UCLA in Los Angeles, said: “To fight ageing, we first need an objective way of measuring it.”
Posted by Xeno on October 19, 2013
A Japanese company has invented carbon wetsuits and lead-based underwear that can protect against radiation amid the growing aftermath of the Fukushima nuclear crisis. It comes as Japan fights to stop the flow of radioactive water leaking into the sea.
Three of the Fukushima plant”s nuclear reactors were damaged by an earthquake-triggered tsunami on March 11, 2011, which led to a nuclear disaster. The plant has been accumulating radioactive water ever since.
Designed in an effort to protect Fukushima clean-up workers, Osaka-based swimwear company Yamamoto Corporation unveiled the anti-radiation garments on Thursday.
The company claims that the wetsuit made from stretchy rubberized kneaded carbon can stop 100 percent of beta radiation.
The swimwear – which weighs only three kilograms – is completely fused so the contaminated water cannot seep through. The suit therefore protects the person wearing it from aftermath illnesses such as cancer, according to its makers.
Yamamoto Corporation is also working on lead-based underwear which protects the lower part of the spine and abdomen from harmful gamma rays. The underwear”s weight is 3.4 kilograms.
“The clothes which protect from two kinds of radiation – beta and gamma rays “”as described above are the first development of such kind in the world,”the company said in a statement.
Due to be released in November, the wetsuit will cost just over US$1,000, while the underwear will cost around $825.
Posted by Xeno on October 10, 2013
The European Prospective Investigation into Cancer and Nutrition, known as EPIC, is a huge ongoing study involving ten countries. Very recently they published in the American Journal of Epidemiology an analysis of vegetable and fruit consumption as it relates to mortality. We’re probably all aware of the benefits of eating vegetables and fruits, but this research is interesting since it highlights the role these foods seem to have in reducing long-term risk of death.
The study was large and long term, including more than 450,000 participants from 10 European countries, who were recruited to the study between the years 1992 and 2000. Researchers followed the participants until the year 2010. Various analysis of the results showed that the more vegetables and fruits consumed by a person, the lower that person’s risk of all-cause mortality. This association, or reduced risk, was even more significant for the risk of death from cardiovascular disease (heart disease and stroke).
The results suggest that a combined total fruit and vegetable consumption of more than 569 grams a day lowers the risk of death by 10% when compared to a consumption of less than 249 grams per day. In addition, for every 200-gram increase in total daily fruit and vegetable consumption, the risk falls by 6%.
When looking at the risk of death from cardiovascular disease, a diet high in vegetables and fruits reduces the risk by 15%. In addition, over 4% of deaths due to cardiovascular disease could be prevented by consuming more than 400 grams total of these foods daily.
Posted by Xeno on October 10, 2013
Seawater just outside one of Japan”s damaged Fukushima Daiichi reactors registered radiation levels on Wednesday 13 times the previous day”s reading, the operator of the crippled nuclear plant said on Thursday.
Japan”s Tokyo Electric Power Company (TEPCO), said combined Cesium-134 and Cesium-137 readings just outside the damaged No. 2 reactor jumped to 1,200 becquerels per liter on Wednesday, the highest levels recorded since late 2011.
Regulatory limits for Cesium, which emits powerful gamma radiation and is potentially fatal to humans, is 90 bq/liter for Cesium-137 and 60 bq/liter for Cesium-134.
A TEPCO spokesman said the sudden spike in radiation was caused by construction work near the No. 2 building, Reuters reported.
News of the spike in radiation levels is the latest setback this week for TEPCO, which has been harshly criticized for its handling of the nuclear disaster in the wake of the massive quake and tsunami that hit the power station in March 2011, triggering three reactor meltdowns.
On Wednesday, six workers were exposed to radiation after a pipe connected to a contaminated water treatment system was mistakenly detached. Reuters estimates that at least 7 tons of water escaped the system.
Earlier, a worker accidentally switched off a water pump used to channel water into the reactor building.
Crews are using chemicals to fortify the soil around the Fukushima reactor buildings – hundreds of meters from the port entrance that connects to the Pacific Ocean – to prevent contaminated water from flowing into the ocean. The pressure from injecting chemicals into the ground forced contaminated soil out into the port area, the spokesman said.
TEPCO also said Cesium-137 readings just outside the silt fence next to the No.2 reactor increased to160 bq/liter, a number that exceeds the regulatory limit and almost double the previous day’s reading.
Radiation from radioactive water leaking from the plant is mostly confined to the harbor around the facility, officials have said.
TEPCO, which is using hundreds of tons of water in an effort to keep the reactors from overheating, has struggled to contain the buildup of radioactive water at the plant.
The accidents at the Fukushima Daiichi plant, situated 220 km (130 miles) from Tokyo, are fueling doubts over TEPCO”s abilities to oversee a hugely complicated cleanup that is expected to take decades.
Last week, the beleaguered Japanese energy company said 430 liters (113 gallons) of contaminated water had leaked from a storage tank at Fukushima and probably flowed to the ocean.
Meanwhile, Japanese officials have said there is no environmental threat to other countries as radiation will be diluted by the sea.
Tokyo, despite lingering concerns over the long-term safety situation at Fukushima, was selected last month to host the 2020 Olympic Games. …