Have Bananas Lost Their Mojo?

Written by Aimee Cremasco

Though their sexy shape may resemble a "GoldMember," modern-day bananas simply aren't shagadellic. According to Belgian and French scientists, bananas may become extinct withinrepparttar next 10 years due to their lack of genetic diversity, which makes them prone to attacks by diseases.

There are two primary fungal diseases attacking banana plantation, Panama disease and black Sigatoka. Biotechnology and genetic manipulation may berepparttar 110128 only way to saverepparttar 110129 fruit. Scientists hope to find disease-resistant genes from a non-edible variation ofrepparttar 110130 banana, and then inject them inrepparttar 110131 edible ones. Unfortunately, it's difficult to develop genetic variance in asexually reproducing plants. Cross-pollination with these wild plants is possible, but scientists claim it won't be easy.

Almost all bananas, as we know them today, are clones of naturally mutant wild bananas, which were discovered as many as 10,000 years ago. This rare mutation caused wild bananas to grow sterile. To keeprepparttar 110132 fruit alive, ancient farmers took cuttings ofrepparttar 110133 mutants, then cuttings ofrepparttar 110134 cuttings, and so on. According to a recent article published in The Guardian, "Plants use reproduction to continuously shuffle their gene pool, building up variety so that part ofrepparttar 110135 species will survive an otherwise deadly disease. Because sterile mutant bananas cannot breed, they do not have that protection."

Shedding Light on Cheaper Solar Energy

Written by Brenda Townsend Hall

Renewable sources of energy arerepparttar key to solving two ofrepparttar 110127 worlds most pressing yet seemingly irreconcilable problems. Onrepparttar 110128 one handrepparttar 110129 developing world needs vastly to increase access to affordable energy because, at present, 1.6 billion people inrepparttar 110130 world's poorest countries do not have a power supply. However, onrepparttar 110131 other, we cannot go on depletingrepparttar 110132 world's finite resources of fossil fuels and contributing torepparttar 110133 emission of harmful greenhouse gases by burning them. Thus sustainable development is threatened by a 'double whammy':repparttar 110134 difficulty of meeting increasing demands for energy, without which development aims cannot be met, andrepparttar 110135 by environmentally harmful systems most often used to provide it.

Affordable, renewable energy sources would contribute greatly to breaking this impasse. However,repparttar 110136 field is a complex one and nobody believes a single solution will be found that can answer allrepparttar 110137 world's energy needs. Even renewable sources have their drawbacks - wind and solar systems, for example, may never be able to stand alone as energy providers because they are, by their very nature, intermittent. However, they can be used very effectively in conjunction with other systems. A judicious mix of energy-producing systems can contribute to sustainable development by increasingrepparttar 110138 availability of energy torepparttar 110139 poor, while reducing harmful impacts onrepparttar 110140 environment. But an intransigent limiting factor isrepparttar 110141 cost, particularly ofrepparttar 110142 conversion of sunlight for energy. If systems are not affordable they will be beyondrepparttar 110143 reach ofrepparttar 110144 poorer countries whose needs are most pressing.

Recently, however, a project undertaken by a team of physicists, chemists, material scientists and engineers at Sheffield Hallam University, with funding fromrepparttar 110145 Engineering and Physical Sciences Research Council (EPSRC), has given a new boost torepparttar 110146 economic feasibility of solar energy. The research has shown how to reducerepparttar 110147 cost of generating solar electricity. Although electricity generation throughrepparttar 110148 interaction ofrepparttar 110149 sun's heat and light with semiconductors (called photovoltaics [PV]) has recognised environmental benefits,repparttar 110150 technology has hitherto been hampered byrepparttar 110151 relatively high costs involved.

Nowrepparttar 110152 Sheffield Hallam University team has come up with some cost-cutting ideas: a low-cost semiconductor production method called electrodeposition, less reliance on expensive semiconductor materials, andrepparttar 110153 identification of alternative solar cell devices and manufacturing techniques with higher conversion efficiencies. Such efficiencies mean that more power can be produced per cell so thatrepparttar 110154 cost of each unit of electricity generated is reduced.

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