Telomerase, even when present, can be turned off with a genetic switch which could be an anti aging breakthrough

Scientists at the Salk Institute have discovered an on-and-off “switch” in cells that may hold the key to healthy aging. This switch points to a way to encourage healthy cells to keep dividing and generating, for example, new lung or liver tissue, even in old age.

In our bodies, newly divided cells constantly replenish lungs, skin, liver and other organs. However, most human cells cannot divide indefinitely–with each division, a cellular timekeeper at the ends of chromosomes shortens. When this timekeeper, called a telomere, becomes too short, cells can no longer divide, causing organs and tissues to degenerate, as often happens in old age. But there is a way around this countdown: some cells produce an enzyme called telomerase, which rebuilds telomeres and allows cells to divide indefinitely.

Scientists at the Salk Institute have discovered that telomerase, even when present, can be turned off.

Genes and Development Journal - Regulated assembly and disassembly of the yeast telomerase quaternary complex



“Previous studies had suggested that once assembled, telomerase is available whenever it is needed,” says senior author Vicki Lundblad, professor and holder of Salk’s Ralph S. and Becky O'Connor Chair. “We were surprised to discover instead that telomerase has what is in essence an ‘off’ switch, whereby it disassembles.”

Understanding how this “off” switch can be manipulated–thereby slowing down the telomere shortening process–could lead to treatments for diseases of aging (for example, regenerating vital organs later in life).

Lundblad and first author and graduate student Timothy Tucey conducted their studies in the yeast Saccharomyces cerevisiae, the same yeast used to make wine and bread. Previously, Lundblad’s group used this simple single-celled organism to reveal numerous insights about telomerase and lay the groundwork for guiding similar findings in human cells.

“We wanted to be able to study each component of the telomerase complex but that turned out to not be a simple task,” Tucey said. Tucey developed a strategy that allowed him to observe each component during cell growth and division at very high resolution, leading to an unanticipated set of discoveries into how–and when–this telomere-dedicated machine puts itself together.

Every time a cell divides, its entire genome must be duplicated. While this duplication is going on, Tucey discovered that telomerase sits poised as a “preassembly” complex, missing a critical molecular subunit. But when the genome has been fully duplicated, the missing subunit joins its companions to form a complete, fully active telomerase complex, at which point telomerase can replenish the ends of eroding chromosomes and ensure robust cell division.

Surprisingly, however, Tucey and Lundblad showed that immediately after the full telomerase complex has been assembled, it rapidly disassembles to form an inactive “disassembly” complex — essentially flipping the switch into the “off” position. They speculate that this disassembly pathway may provide a means of keeping telomerase at exceptionally low levels inside the cell. Although eroding telomeres in normal cells can contribute to the aging process, cancer cells, in contrast, rely on elevated telomerase levels to ensure unregulated cell growth. The “off” switch discovered by Tucey and Lundblad may help keep telomerase activity below this threshold.

Abstract - Regulated assembly and disassembly of the yeast telomerase quaternary complex

The enzyme telomerase, which elongates chromosome termini, is a critical factor in determining long-term cellular proliferation and tissue renewal. Hence, even small differences in telomerase levels can have substantial consequences for human health. In budding yeast, telomerase consists of the catalytic Est2 protein and two regulatory subunits (Est1 and Est3) in association with the TLC1 RNA, with each of the four subunits essential for in vivo telomerase function. We show here that a hierarchy of assembly and disassembly results in limiting amounts of the quaternary complex late in the cell cycle, following completion of DNA replication. The assembly pathway, which is driven by interaction of the Est3 telomerase subunit with a previously formed Est1–TLC1–Est2 preassembly complex, is highly regulated, involving Est3-binding sites on both Est2 and Est1 as well as an interface on Est3 itself that functions as a toggle switch. Telomerase subsequently disassembles by a mechanistically distinct pathway due to dissociation of the catalytic subunit from the complex in every cell cycle. The balance between the assembly and disassembly pathways, which dictate the levels of the active holoenzyme in the cell, reveals a novel mechanism by which telomerase (and hence telomere homeostasis) is regulated.

19 Pages of Supplemental Material

Sources: Salk Institute for Biological Studies, Genes and Development journal

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John Bongaarts at the Population Council thinks Climate Change has a good chance of limiting human Population but he is wrong

According to the new analysis by researchers at the United Nations and several academic institutions, there is an 80 percent chance that the world’s population, now 7.2 billion, won’t stop at nine billion in 2050, but will instead be between 9.6 billion and 12.3 billion by 2100. The researchers increased their estimates after noting persistent high birth rates and faster-than-expected progress in combatting HIV/AIDS in Africa. [Journal Science - World population stabilization unlikely this century]

Technology Review David Talbot says the prediction’s reliability is debatable, given that it does not take into account future hardships a large population would likely face. It doesn’t take into account the effects of climate change, food shortages, disease, or conflict. The study take into account that population growth could trigger deadly calamities like food shortages, war, and disease even without climate change, says John Bongaarts, vice president and distinguished scholar at the Population Council, a think tank and research organization based in New York City.

Wolfgang Lutz, director of the Vienna Institute of Demography, says, his newest analysis still suggests a less-dire outcome. “Our most likely scenario comes out somewhat lower than the current United Nations projections,” and suggests population will peak at 9.4 billion around 2070 and start a slow decline to nine billion by the end of the century.

So Lutz at the Vienna Demography Institute calls a human population rising to 12 billion in 2100 a dire outcome. It would be dire if wars, food shortages, disease and climate change do not limit population ? Or if Africa does not see vastly increased usage of birth control ?



Birth rates are suppressed during big wars but studies show that there is an increase in birth rates after the war and population levels recover.

Birth rates and populations also bounce back after famines.

Bongaarts seems to be hoping or expecting permanent wars and famines.

Africa has more wars and famines than other places in the world. This is one of the reasons that the birth rates stay high. People are worried that they will lose children. So they have 5-6 kids hoping that 2-3 will survive. When survival rates are good then birth rates are low. A lot of wars and famine and hardship means that people will have more kids and not less and population will be higher. There would have to be a complete global collapse for the population to drop and stay down. Bongaarts underestimates what people can do.

Large scale fish farming and ocean management (iron fertilization of the ocean to boost fish).
Bongaarts does not realize that all of the CO2 emissions and climate effects are side effects of our civilization. This is happening without that as a goal. Of course the technology exists and can be developed for changing the climate and the oceans to what we want. It is about getting the most economic and efficient solutions.

Ocean Acidification can be mitigated

Climate change can be mitigated.

Correcting soot pollution is 20 times cheaper than fixing the CO2

The World can support one hundred billion living at western levels and expected improvements in agriculture, energy and water can easily handle 15-20 billion by 2100.


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First Water-Based Nuclear Battery Can Be Used to Generate Electricity for decades with betavoltaics breakthrough

From cell phones to cars and flashlights, batteries play an important role in everyday life. Scientists and technology. companies constantly are seeking ways to improve battery life and efficiency. Now, for the first time using a water-based solution, researchers at the University of Missouri have created a long-lasting and more efficient nuclear battery that could be used for many applications such as a reliable energy source in automobiles and also in complicated applications such as space flight.

The battery uses a radioactive isotope called strontium-90 that boosts electrochemcial energy in a water-based solution. A nanostructured titanium dioxide electrode (the common element found in sunscreens and UV blockers) with a platinum coating collects and effectively converts energy into electrons.

“Water acts as a buffer and surface plasmons created in the device turned out to be very useful in increasing its efficiency,” Kwon said. “The ionic solution is not easily frozen at very low temperatures and could work in a wide variety of applications including car batteries and, if packaged properly, perhaps spacecraft.”

The maximum energy conversion efficiency of the MU battery was approximately estimated to be 53.88%. This is an astonishing number for a first trial design. Strontium 90 has a half life of 28.79 years

H/T to New Energy and Fuel

Nature Scientific Reports - Plasmon-assisted radiolytic energy conversion in aqueous solutions


ABSTRACT

The field of conventional energy conversion using radioisotopes has almost exclusively focused on solid-state materials. Herein, we demonstrate that liquids can be an excellent media for effective energy conversion from radioisotopes. We also show that free radicals in liquid, which are continuously generated by beta radiation, can be utilized for electrical energy generation. Under beta radiation, surface plasmon obtained by the metallic nanoporous structures on TiO2 enhanced the radiolytic conversion via the efficient energy transfer between plasmons and free radicals. This work introduces a new route for the development of next-generation power sources.


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Optimizing performance and working around limitation of Dwave Quantum Annealing Computers

Discrete optimization using quantum annealing on sparse Ising models

This paper discusses techniques for solving discrete optimization problems using quantum annealing. Practical issues likely to affect the computation include precision limitations, finite temperature, bounded energy range, sparse connectivity, and small numbers of qubits. To address these concerns they propose a way of finding energy representations with large classical gaps between ground and first excited states, efficient algorithms for mapping non-compatible Ising models into the hardware, and the use of decomposition methods for problems that are too large to fit in hardware. They validate the approach by describing experiments with D-Wave quantum hardware for low density parity check decoding with up to 1000 variables.

They have outlined a general approach for coping with intrinsic issues related to the practical use of quantum annealing. To address these issues we proposed methods for finding Ising problem representations that have a large classical gap between ground states and first excited states, practical methods for embedding Ising models that are not compatible with the hardware graph, and decomposition methods to solve problems that are larger than the hardware. As an application of our techniques, we described how we implemented LDPC decoding problems in D-Wave hardware. Our approach has enabled us to solve LDPC decoding problems of up to 1000 variables. The current hardware implementation of QA tested here is roughly as fast as an efficient implementation of simulated annealing, but these results offer the promise of hybrid quantum/classical algorithms that surpass purely classical solution as QA hardware matures.

As future work, they would like to improve upon the scalability of the current method for constructing penalty functions with large gaps. This would allow larger component subproblems and reduce the need for minor embedding between subproblems. Further, the methods they ave described here for finding penalty functions assume an assignment of decision variables to qubits. Different assignment choices lead to different results and different hardware performance. They do not currently have an effective method for this assignment.

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POSTED BY BRIAN WANG AT 9/19/2014

Acidification Mitigation Details and lower cost mitigation in the $1 to 4 per ton CO2 ranges

Ocean Acidification: Cause, Impact and mitigation from IIT Kanpur

Limestone mitigation

Presentation by Rau describes the limestone mitigation method

Journal of Geophysical Research - Mitigating the atmospheric CO2 increase and ocean acidification by adding limestone powder to upwelling regions

The feasibility of enhancing the absorption of CO2 from the atmosphere by adding calcium carbonate (CaCO3) powder to the ocean and of partially reversing the acidification of the ocean and the decrease in calcite supersaturation resulting from the absorption of anthropogenic CO2 is investigated. CaCO3 could be added to the surface layer in regions where the depth of the boundary between supersaturated and unsaturated water is relatively shallow (250–500 m) and where the upwelling velocity is large (30–300 m a 1 ). The CaCO3 would dissolve within a few 100 m depth below the saturation horizon, and the dissolution products would enter the mixed layer within a few years to decades, facilitating further absorption of CO2 from the atmosphere. This absorption of CO2 would largely offset the increase in mixed layer pH and carbonate supersaturation resulting from the upwelling of dissolved limestone powder. However, if done on a large scale, the reduction in atmospheric CO2 due to absorption of CO2 by the ocean would reduce the amount of CO2 that needs to be absorbed by the mixed layer, thereby allowing a larger net increase in pH and in supersaturation in the regions receiving CaCO3. At the same time, the reduction in atmospheric pCO2 would cause outgassing of CO2 from ocean regions not subject to addition of CaCO3, thereby increasing the pH and supersaturation in these regions as well. Geographically optimal application of 4 billion t of CaCO3 a 1 (0.48 Gt C a 1 ) could induce absorption of atmospheric CO2 at a rate of 600 Mt CO2 a 1 after 50 years, 900 Mt CO2 a 1 after 100 years, and 1050 Mt CO2 a 1 after 200 years.

Opportunities for Low-Cost CO2 Mitigation in Electricity, Oil, and Cement Production by Rau

Several low-cost opportunities exist for scrubbing CO2 from waste gas streams, utilizing spontaneous chemical reactions in the presence of water and inexpensive or waste alkaline compounds. These reactions convert CO2 to bicarbonate or carbonate in dissolved or solid form, thus providing CO2 capture and low-risk CO2 storage underground, in the ocean, or in some cases on land. Useful by-products and co-benefits can also be generated by these processes. In certain settings this approach will be significantly less energy intensive, less costly, and less risky than "conventional" molecular CO2 capture and geologic storage.

It has been previously shown that industrial-scale accelerated weathering of limestone, AWL, can effectively convert a significant fraction of US CO2 emissions to long-term storage as bicarbonate in the ocean. Being analogous to the successful, wide-spread use of wet limestone to desulfurize flue gas, AWL reactors could be retrofitted to existing power plants at a cost possibly as low as $3-$4 per tonne CO2 mitigated. Such low costs would especially pertain to coastal power plants where an average of 30,000 tonnes of seawater per GWhe are already pumped through for cooling, and where the majority of coastline (at least in the US) is within 400 km of limestone sources.

Capture and Storage Using Water Co-Produced With Oil

On average 10 barrels of water are brought to the surface with each barrel of oil produced, and the majority of this water is simply pumped back into the reservoir. Our preliminary analysis suggests that most of this water is significantly undersaturated in CO2 relative to industrial waste gas streams that are typically 10% to 20% CO2. Furthermore, such waters can contain significant carbonate ion concentrations, meaning they have an enhanced capacity to react with excess CO2 to form dissolved bicarbonates.

While the US capacity of this CO2 mitigation approach is modest (perhaps 2 million tons/yr) and is best suited to treat CO2 waste streams in the immediate vicinity of the water production, the cost of such CO2 mitigation could be extremely low, perhaps less than $1/tonne CO2.

Co-benefits of CO2 addition to produced water would be the reduction (via lowered pH) of internal pipeline scale formation, a common and expensive problem in the industry. Also, CO2 addition could enhance the oil-water separation process, may reduce downstream microbial fouling, and might enhance oil recovery. Further work is needed to better evaluate the cost/benefit and potential market of this CO2 mitigation approach.

Cement Production can be altered to absorb CO2 instead of releasing CO2.

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Google U lab could partner with countries for new more efficient cities

The Information reports in 2013, Google CEO Larry Page convened his direct reports, the company’s dozen or so senior vice presidents, for a project that would take up two days a week for a couple of months. About 100 other employees below the SVP rank also participated in the effort, dubbed Google 2.0.

Google 2.0 has goals in areas ranging from subscription businesses to location services to developing replacements for traditional passwords.

It also setup a second research lab Google Y. Google Y is looking at more efficient airports and cities.




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POSTED BY BRIAN WANG AT 9/19/2014

No Independence for Scotland

BBC News has called the Scotland independence vote for the NO. The vote was 55% No and 45% Yes with 85% of the vote counted.


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POSTED BY BRIAN WANG AT 9/18/2014