Botryococcus braunii, a green colonial microalga, is an unusually rich renewable source of hydrocarbons and other chemicals. Hydrocarbons can constitute up to 75% of the dry mass of B. braunii. This review details the various facets of biotechnology of B. braunii, including its microbiology and physiology; production of hydrocarbons and other compounds by the alga; methods of culture; downstream recovery and processing of algal hydrocarbons; and cloning of the algal genes into other microorganisms. B. braunii converts simple inorganic compounds and sunlight to potential hydrocarbon fuels and feedstocks for the chemical industry. Microorganisms such as B. braunii can, in the long run, reduce our dependence on fossil fuels and because of this B. braunii continues to attract much attention.

Indirect ophthalmoscopy should be performed at 4 weeks of post natal age in all preterm babies with birth weight < or = 1500 gm, and intensified in the presence of risk factors like oxygen administration, apnoea and septicemia.

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Fungi are one of the most neglected pathogens apparent from the fact that the Amphotericin B, a polyene antibiotic, discovered way back in 1956 is still used as a 'gold standard' for antifungal therapy. Past two decades have witnessed a dramatic rise in the incidences of life threatening systemic fungal infections. This can be ascribed to the increase in the number of immuno-compromised patients due to rise in HIV infected population, cancer chemotherapy and indiscriminate use of antibiotics. Majority of clinically used antifungals suffer from various drawbacks in terms of toxicity, efficacy and cost, and their frequent use has led to the emergence of resistant strains. Hence, there is a great demand for novel antifungals belonging to wide range of structural classes, selectively acting on novel targets with fewer side effects. This article aims at reviewing recent efforts made towards discovering novel antifungal drug targets and investigational molecules acting on them.

Non-linear stability of the libration point L4 of the restricted three-body problem is studied when the more massive primary is an oblate spheroid with its equatorial plane coincident with the plane of motion. Moser's conditions are utilised in this study by employing the iterative scheme of Henrard for transforming the Hamiltonian to the Birkhoff's normal form with the help of double D'Alembert's series. It is found that L4 is stable for all mass ratios in the range of linear stability except for the three mass ratios:= 0.0242 .... 0.1790. #c2 = 0.0135 .... 0.0993. #c3 = 0.0109 .... 0.0294. AI~ Al, Al.

Volcanic rock and mantle xenolith compositions in the Sierra Nevada (western United States) contradict a commonly held view that continental crust directly overlies asthenosphere beneath the Sierran range front, and that ancient continental mantle lithosphere (CML) was entirely removed in the Pliocene. Instead, space-time trends show that the Walker Lane is the principle region of mantle upwelling and lithosphere removal in eastern California, that lithosphere loss follows the migration of the Mendo cino Triple Junction (MTJ), and that the processes of lithosphere removal are not yet complete beneath the Sierra Nevada and its range front. Key evidence is provided by volcanic rock compositions. The 87 Sr/ 86 Sr ratios for mafi c volcanics of the Sierra (MgO > 8%) are mostly > 0.705, and 143 Nd/ 144 Nd < 0.5127, much unlike eastern sub-Pacifi c asthenosphere (where 87 Sr/ 86 Sr < 0.7027 and 143 Nd/ 144 Nd > 0.5129), but very much like CML. Similarly, Sierran volcanics carry CML-like trace element ratios, with La/Nb > 3 and Th/Nb > 1, values that are signifi cantly higher than asthenosphere-derived melts (La/Nb < 1.5, Th/Nb < 0.08). Spinel-bearing mantle xenoliths contained in Pleistocene-Holocene volcanics from the Sierran range front also have a CML composition, with 87 Sr/ 86 Sr and ε Nd ratios that range to 0.7065 and-3.6, respectively. New estimates of melt extraction depths using Si activity and mineralogy-sensitive trace element ratios (Sm/Yb, Lu/Hf) show that CML extends from the base of the crust (40 km) to depths of 75 km beneath the range front, and to 110 km for Pliocene volcanics of the southern Sierra. This means that garnet-bearing lithologies could not have been dislodged from beneath the southern Sierra until after the Pliocene. Only in the Walker Lane do young (0.18 Ma) volcanic rocks, from the Coso volcanic fi eld, approach asthenosphere-like compositions, which occurs only 20 Ma after MTJ arrival. Temporal trends show that MTJ arrival at any given latitude south of 37°N signals lithosphere heating, probably due to asthenosphere that upwells to replace the sinking Farallon plate. Partial melts of the asthenosphere, and perhaps the asthenosphere itself, intrude into and cause heating and partial melting of overlying CML; this culminates after 10 Ma. After 20 Ma, CML becomes highly degraded and asthenosphere-derived melts are dominant. North of 37°N, volcanic rocks approach asthenosphere-derived compositions to the west, not the east, and 87 Sr/ 86 Sr ratios increase from 18 to 0 Ma, indicating that this region has entered a phase of lithosphere heating, but not yet a phase of lithosphere removal. We propose a new model of lithosphere degradation, where asthenosphere or its partial melts pervasively invade CML beneath the Walker Lane. This process is now nearly complete beneath Coso, and is migrating west, so that it is only partly complete at the southern Sierra range front, or within the Sierra Nevada, at any latitude. This model of intermixed asthenosphere and lithosphere better explains the comp...

Phenyl and aryl substituents considerably extend the charge delocalization of the transition state. In compounds with phenyl substituents on both C-3 and nitrogen [e.g. (14) and (9) Li, D, Cl, or Br are noted.