In the face of increasing CO 2 emissions from conventional energy (gasoline), and the anticipated scarcity of crude oil, a worldwide effort is underway for cost-effective renewable alternative energy sources. Here, we review a simple line of reasoning: (a) geologists claim that much crude oil comes from diatoms; (b) diatoms do indeed make oil; (c) agriculturists claim that diatoms could make 10-200 times as much oil per hectare as oil seeds; and (d) therefore, sustainable energy could be made from diatoms. In this communication, we propose ways of harvesting oil from diatoms, using biochemical engineering and also a new solar panel approach that utilizes genomically modifiable aspects of diatom biology, offering the prospect of "milking" diatoms for sustainable energy by altering them to actively secrete oil products. Secretion by and milking of diatoms may provide a way around the puzzle of how to make algae that both grow quickly and have a very high oil content.

Abstract:Two new freshwater species of Achnanthidium Kützing are described from Eastern Ghats Mountain range of Peninsular India based on light and scanning electron microscopy observations. Achnanthidium initium sp. nov. belongs to the group of Achnanthidium taxa that have terminal raphe fissures curved to opposite sides of the valve. This taxon is characterized by distinctive fascia, raphe endings extending to the valve margin, lineate distal raphe endings and 2-5 linear areola per striae. Achnanthidium linannulum sp. nov. belongs to the group of Achnanthidium taxa with terminal raphe fissures curved to the same side of the valve. This species is characterized by the presence of occluded areolae near the margin, striae orientation and the weakly bent internal distal ends of the raphe. These new species are known only from their type locality, oligotrophic Masilla Waterfalls from Kolli Hills, Eastern Ghats.

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GENERAL ⎜ ARTICLEThe water-repellent surface of lotus (Nelumbo nucifera) leaf and flower is due to nanosized wax papillae on the upper side of each epidermal cell. As a result, raindrops make a high contact angle with the papillae and roll off carrying dust and dirt particles, leaving the surface clean. This self-cleaning property of highly hydrophobic surfaces, termed as the lotus effect, has opened the possibilities of fabricating superhydrophobic surfaces for a variety of products.Lotus, botanically named Nelumbo nucifera, is regarded as a sacred plant in Hindu mythology. Lotus is also India's national flower ( Figure 1) and is regarded as a symbol of purity. Its leaf and flower are water-repellant. A falling raindrop turns into a water bead and rolls off, taking along with it the dust and the dirt particle. Hence, despite growing in muddy waters, the lotus leaf surface stays relatively clean (Figure 2).Although the water repellency of lotus had long been recognized, its scientific basis was understood only in 1997 [1] when two botanists, Wilhelm Barthlott ( Figure 3) and Christoph Neinhuis, at the University of Bonn in Germany examined leaf surfaces of lotus and several other plants using a scanning electron microscope which resolves structures as small as 1-20 nm (one nm = billionth or 10 -9 of a meter). They established that the selfcleaning property is due to the presence of convex papillae on the surface of leaves, coated with wax crystals of nanoscopic dimension: ~10 to ~100 nm (Figure 4). The papilla greatly reduces the contact area of water droplets with it. The water droplet, as for example due to rain or fog or dew, is dislodged, often coalescing into a bigger drop at the center of leaf surface that falls off with swaying of the leaf.Wax is comprised of a mixture of long-chain hydrocarbons: Figure 1. Lotus, the national flower of India featured on a postage stamp issued on September 1, 1977.

Abstract:A study was made of the type material of Achnanthidium exiguum (Grunow) CzarneCKi. This often encountered and apparently ubiquitous species was originally described as Stauroneis exilis by KüTzinG from the island of Trinidad and later re-named as Achnanthes exigua by Grunow. The type material for this taxon (KüTzinG sample 397), housed in the Van heurCK collection at the National Botanic Garden of Belgium, Meise was investigated and the ultrastructure of this taxon was documented using both LM and SEM observations. A new Antarctic taxon, formerly identified as A. exigua, was described as a new species, Achnanthidium australexiguum sp. nov. The position of both taxa within the genus Achnanthidium is briefly discussed.