Artificial Leaf. Will it be the Energy source of the future ?

Artificial Leaf: the new ways of producing energy

At the very beginning of the human race, concurring the energy source was the ultimate target. And still we are racing behind a renewable, affordable energy source. We already witnessed wars and fight for capturing energy sources and witnessed the rise of economical power of the world  from scratch  just becuse of having the natural energy resources.

The world is and will be highly worried about the avaialbility of the natural resources. The depresiation of the resources is really an unforgatable thoughts. But still we are not able to come up with a replaceble source for natural resources. One advantage of liquid fuel is propotrion of stored energy in it  and storage space required.  To use elctric current insted of liquid fuel to fly a flight, just imagine the amount for batteries required to store the power. So the real though is to come up with a real alternate energy source  which is to be efficient, cheap and robust. And it is the ultimate challenge for the existance of the entire humnity.

In recent publication of Nature, discused about a concept of Artificial leaf. This leaf is just not a leaf made of synthetic material, the artifical part is the functionality of the leaf. Yes we are trying to mimic the function of a leaf 'the photosysnthesis'. Ultimately the energy source we are looking for the solar energy.

The concept of artificial photosynthesis goes back to 1912, but the push to achieve it did not start until 1972, when Japanese researchers outlined what a device would need to take in sunlight and use it to split water into oxygen and hydrogen fuel2. Progress was slow. In 1998, Turner reported3 a complete system that showed a major advance — it stored 12% of the incoming solar energy as fuel, compared with 1% of energy stored as biomass in real leaves. But it cost more than 25 times too much to be competitive, and its performance dropped off after 20 hours of sunshine.

In the process, to create a system that is much cheaper than just splitting water with electricity from a solar panel. At the heart of JCAP's artificial-leaf design are two electrodes immersed in an aqueous solution. Typically, each electrode is made of a semiconductor material chosen to capture light energy from a particular part of the solar spectrum, and coated with a catalyst that will help to generate hydrogen or oxygen at useful speeds (see 'Splitting water'). Like many other artificial-photosynthesis devices, JCAP's system is divided by a membrane to keep the resulting gases apart and reduce the risk of an explosive reaction.

Once the water has been split, the hydrogen is harvested. It can be used as a fuel by itself — perhaps in hydrogen-powered cars.

Making any one of the artificial leaf's components work well is a challenge; combining all of them into a complete system is even harder. Much of the difficulty comes down to finding the right materials. Silicon, for instance, makes a good photocathode — the electrode that produces hydrogen gas — but is stable only when the solution around it is acidic. Unfortunately, the situation is reversed with photoanodes, which produce oxygen: the good ones are stable only when the solution is basic, not acidic. And the best catalyst for the oxygen-producing electrode, iridium, is both rare and expensive, which makes it unsuitable for commercial-scale devices.

Light industry

Another entrant in the artificial-photosynthesis field is the Japan Technological Research Association of Artificial Photosynthetic Chemical Process (ARPChem), a consortium of universities and companies that has government funding comparable to JCAP's grant — although over ten years rather than five — to develop a bag-based approach. Kazunari Domen, a chemist at the University of Tokyo and leader of ARPChem's water-splitting group, says that one of the companies in the consortium has been working on a membrane to separate the hydrogen and oxygen products.
Other projects are making photoabsorbers from organic molecules, rather than semiconductors. Some are building molecular assemblies inspired directly by the photosynthetic apparatus of plants. And in the past few years, a class of materials called perovskites has drawn the attention of the solar-photovoltaic community for its high energy-conversion efficiency; some researchers think that the materials also have potential in artificial photosynthesis.
Daniel Nocera, a chemist at Harvard University in Cambridge, Massachusetts, launched Sun Catalytix to develop his work on a low-cost catalyst. But the company announced last year that it has put that research on hold to pursue a less challenging product with prospects of turning a profit for investors sooner. The decision underscores the challenges of bringing a commercially viable artificial-photosynthesis system to market.


 

Artificial Leaf. Will it be the Energy source of the future ?

9:47 PM Artificial leaf, energy, fuel, solar energy, splitting water

Phage Therapy -Drug resistant bacterial diseases

Phage Terapy gets revitalized

 

The century old virus treatment is on high interset on the increasing drug resistance bactereia. Reports says the rastic mutaion in bacterial genome againt the antibiotics and reserches are spending a lot of time and resource on developing new drugs each and every time to tackle the diseases.


Bacterio Phage

Now the thoughts of using the century old virus treatment- use of bacterio phages- phages are virus which infects on bacteria- to treat for bacterial diseases. bacteria — to treat infections. Phage therapy is still widely used in Russia, Georgia and Poland, but never took off elsewhere. Pages are viruses and peoples are afrid of viruses.

Now, faced with the looming spectre of antibiotic resistance, Western researchers and governments are giving phages a serious look. In March, the US National Institute of Allergy and Infectious Diseases listed phage therapy as one of seven prongs in its plan to combat antibiotic resistance. And at the American Society for Microbiology (ASM) meeting in Boston last month, Grégory Resch of the University of Lausanne in Switzerland presented plans for Phagoburn: the first large, multi-centre clinical trial of phage therapy for human infections, funded by the European Commission.

Previous lack of Western interest to clinicians’ preference for treating unknown infections with broad-spectrum antibiotics that kill many types of bacterium. Phages, by contrast, kill just one species or strain. But researchers now realize that they need more precise ways to target pathogenic bacteria, says microbiologist Michael Schmidt of the Medical University of South Carolina in Charleston. Along with the rising tide of strains resistant to last-resort antibiotics, there is growing appreciation that wiping out the human body’s beneficial microbes along with disease-causing ones can create a niche in which antibiotic-resistant bacteria can thrive. “Antibiotics are a big hammer,” Schmidt says. “You want a guided missile.”

Finding a phage for a bacterial target is relatively easy, Young says. Nature provides an almost inexhaustible supply: no two identical phages have ever been found. As a bacterium becomes resistant to one phage — by shedding the receptor on the cell surface that the virus uses to enter — the Eliava Institute researchers simply add more phages to the viral cocktails that patients receive. Kutateladze says that they update their products every eight months or so, and do not always know the exact combination of phages that make up the cocktail.

In initial trials, the researchers found that their phage could kill more than 99% of the E. coli cells that contained specific anti­biotic-resistance gene sequences, whereas it left susceptible cells alone. Giving the phage to waxworm larvae infected with resistant E. coli increased the worms’ chance of survival. The researchers are now starting to test the system in mice (human trials are a long way off).

Phge therapy never replaces antibiotics . But it definitly gives and added advantage over the drug resistance strains of bacteria.

Phage Therapy -Drug resistant bacterial diseases

4:07 PM antibiotic resistance, bacterio phage therapy, diseases, drug resistance, mutaion, virus

Evolutionary relationships among some of the organisms

Evolutionary relationships among some of the organisms

The branches of the evolutionary tree show paths of descent but do not indicate by their length the passage of time. (Note, similarly, that the vertical axis of the diagram shows major categories of organisms and not time.)

Evolutionary relationships among some of the organisms

Evolutionary relationships among some of the organisms

2:36 PM Evolutionary relationships among some of the organisms

Stem cell Approch for Parkinson’s disease

Stem cell approch is gaining momentem in Parkinson’s disease curation

 

  Parkinson’s disease (PD) is a degenarative disorder of central nervous system. PD is often described as idiopathic - means no known causes- , although some atypical cases have a genetic origin. The motor symptoms of Parkinson's disease result from the death of dopamine-generating cells in the substantia nigra, a region of the midbrain, the cause of this cell death is unknown.


Mid Brain Cross Section

Early in the course of the disease, the most obvious symptoms are movement-related; these include shaking, rigidity, slowness of movement and difficulty with walking and gait. Later, thinking and behavioral problems may arise, with dementia commonly occurring in the advanced stages of the disease, whereas depression is the most common psychiatric symptom. Other symptoms include sensory, sleep and emotional problems. Parkinson's disease is more common in older people, with most cases occurring after the age of 50.

The Stem Cell Approch

Penelope Hallett of Harvard University and McLean Hospital in Belmont, Mass., and colleagues studied postmortem brain tissue from five people with advanced Parkinson’s. The five had received stem cell transplants between four and 14 years earlier. In all five people’s samples, neurons that originated from the transplanted cells showed signs of good health and appeared capable of sending messages with the brain chemical dopamine, a neurotransmitter that Parkinson’s depletes.    

                                                                      

Results are mixed about whether these transplanted cells are a good way to ease Parkinson’s symptoms. Some patients have shown improvements after the new cells stitched themselves into the brain, while others didn’t benefit from them. The cells can also cause unwanted side effects such as involuntary movements


 

Stem cell Approch for Parkinson’s disease

11:41 AM degenarative disorder of central nervous system, dopamine-generating, idiopathic, midbrain, Parkinson’s disease, substantia nigra

The Twist of Twisted Helix

Twisting og Helix, Hemihelix with Single and Multiple Perversion 

 

Helix is a well known structure in biology. There are different types of helices structures exisits in the universe. The nature always choose for stable structure. Helix is the basic structure of DNA. But helix formation can get complicated, as helix grows. The rotation of helices may get reversed and the resulting structure has een dubbed hemihelix. And we can create it very simply by untwisting a part of our telephone cord.

Katia Bertoldi, a professor of applied mechanics at Harvard University, and her colleagues wanted to see how hemihelices form on their own. So they stretched a strip of silicone rubber, glued it to a second, unstretched strip and let the pair go. The researchers reported April 23 in PLOS ONE that they could get a range of shapes to form by tuning the dimensions of the glued rubber pieces.

Strips that were much thicker than they were wide spiralled gently to form helices. Those with squarer cross sections relaxed themselves with a strong twist, forming hemihelices with one or many regularly spaced changes in direction.
“It’s sort of a competition between bending and twisting,” Bertoldi says. She and her colleagues are now experimenting with rectangular patches of rubber to see how this same stretch-and-release approach can be applied to make other three-dimensional shapes.

Spiral-bound

To create helical structures, one silicone strip (red) is stretched to match the length of a longer strip (blue). The pair is glued together and then released. Depending on the dimensions of the strands, a helix or hemihelix (one shown right) forms as the pair relaxes.

Shape matters

The number of changes in direction, or “perversions,” in a hemihelix depends on the cross section of the bonded strips (shown actual size below). Keeping width constant (blue = 3 mm, red = 1.89 mm), researchers decreased the thickness of the strips (shown as height) for more perversions.







 

The Twist of Twisted Helix

10:57 AM DNA, helices, Helix, Hemihelix, perversion, Twist of helix