The effects of enhanced ultraviolet-B (UV-B, 0.4 W m -2 ) irradiance and nickel (Ni, 0.01, 0.10 and 1.00 mM; Ni 0.01 , Ni 0.10 , Ni 1.00 , respectively) treatment, singly and in combination, on growth, photosynthetic electron transport activity, the contents of reactive oxygen species (ROS), antioxidants, lipid peroxidation, and membrane leakage in soybean seedlings were evaluated. Ni 0.10 and Ni 1.00 and UV-B declined the growth and chlorophyll content, which were further reduced following combined exposure. Contrary to this, Ni 0.01 stimulated growth, however, the effect together with UV-B was inhibitory. Carotenoids showed varied response to both the stresses. Simultaneous exposure of UV-B and Ni as well as UV-B alone reduced the activities of photosystems 1 and 2 (PS1 and PS2) and whole chain activity significantly, while Ni individually, besides strongly inhibiting PS2 and whole chain activity, stimulated the PS1 activity. Both the stresses, alone and together, enhanced the contents of superoxide radical ( − ⋅ 2 O ), hydrogen peroxide (H 2 O 2 ), malondialdehyde (MDA), electrolyte leakage, and proline content, while ascorbate content declined over control. Individual treatments increased the activities of catalase (CAT), peroxidase, and superoxide dismutase (SOD), but Ni 1.00 declined SOD activity significantly. Combined exposure exhibited similar response, however, CAT activity declined even more than in control. Compared to individual effects of UV-B and Ni, the simultaneous exposure resulted in strong inhibition of photosynthetic electron transport and excessive accumulation of ROS, thereby causing severe damage to soybean seedlings.

Ab stractUV-B and cad mium, alone and to gether, in duced changes in photosynthetic pig ment lev els, photosynthetic elec tron transport ac tiv ity, en zy matic and non-en zy matic (low mo lec u lar weight) an ti ox i dants, level of hy dro gen per ox ide and lipid peroxidation in Riccia sp. were eval u ated. Chlo ro phyll con tent was found to de crease with the ris ing con cen tra tion of cadmium and UV-B ex po sure alone and its level fur ther de clined when both the stresses were ap plied to gether. In con trast to this, ca rot en oids ex hib ited var ied re sponse, as it showed enhance ment with UV-B (15, 30 and 45 min ex po sure) and low con cen tra tion of Cd (1 and 10 µM) treat ment alone and in combi na tion. Both the stresses caused strong in hib i tory ef fect on PS II ac tiv ity (H 2 O → p-BQ), while PS I ac tiv ity (DCPIP/ASC → MV) ap peared to be less sen si tive. To tal per ox ide con tent in creased with si mul ta neous in crease in lipid peroxidation. The level of non-en zy matic an ti ox i dant ascorbate and en zymatic an ti ox i dants superoxide dismutase and peroxidase ac tivity were found to in crease with si mul ta neous de crease in catalase ac tiv ity fol low ing UV-B and Cd treat ments. These results in di cate that 45 min of UV-B ex po sure and 10, 100 and 1000 µM cad mium alone and to gether, strongly ar rested electron flow through PS II which caused ac cel er ated gen er a tion of re ac tive ox y gen spe cies (H 2 O 2 ) and ex cess ac cu mu la tion of H 2 O 2 due to sig nif i cant in hi bi tion of catalase ac tiv ity, led to the ox i da tive dam age in Riccia sp.

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Differential physiological and biochemical responses of two Vigna spp. i.e. Vigna mungo (L.) and Vigna acontifolia (Jacq.) seedlings exposed to enhanced ultraviolet-B (ambientþsupplemental, 280e320 nm) radiation were studied. UV-B radiation accelerated the generation of ROS i.e. superoxide radical (O 2 e), hydrogen peroxide (H 2 O 2) and hydroxyl radical (OH) in leaves, and concomitantly damaging effects on lipid peroxidation, electrolyte leakage and growth in both Vigna spp. were noticed in dose dependent manner, but V. mungo exhibited greater UV-B damaging effects. UV-B stress induced positive response on antioxidants: superoxide dismutase (SOD) and guaiacol peroxidase (GPX) activity, and contents of proline, ascorbic acid, total phenolic contents (TPCs) and total flavonoid contents (TFCs) in leaves of both spp., however, catalase (CAT) exhibited varied activity. The study concludes that substantially higher contents of TPCs and TFCs in epidermal layer, proline and ascorbic acid, and higher CAT activity before and after enhanced UV-B exposure probably attributed greater tolerance to V. acontifolia species, thus exhibited lesser UV-B induced damaging effects on cellular components and growth than that of V. mungo. This study also suggests that V. acontifolia is comparatively resistant to UV-B and thus may be useful for practical cultivation.

Visionary leadership has emerged as a key determinant o.fcorporate survival, success andgrowth in today 's turbulent environment. Successful leaders of the 21.\'1 century have the capacity to create vision and also translate it into reality. Visionary leadership is transformative and based on the power ofinspiration. It is characterized by: a commitment to core spiritual values, with a clear vision, respect for empowering relationship, followed by courageous and innovative action. From an Indian perspective, it is marked by an act ofleading from the front, benevolence from within, respectful pluralism, continuous introspection and focus on legacy. It involves a dynamic, interactive process. As a visionary leader, Dr. A.P.J. Abdul Kalam substantially changed the organizational climate of DRDL prior to launching Integrated Guided Missile Development Programme (IGMDP) using effective communication and providing clear direction to the various teams involved. Later on, a highly performing eli/nate emerged, when he used further indigenous techniques to manage technology for accomplishing outstandingperformance. The techniques used were technology-oriented structure, searchfor capable project leaders, Science Council (Panchayat), collaborative (partnership) effort, transformation oforganizational dynamics by empowering scientists, motivation, etc. The outstanding success ofDRDL is evidenced by the fact that the country acquired the capability ofInaking five state-of-the-art missile systems in record time. The visionary leadership style of Dr. Kalam is comparable to that of George Washington, the founding father of the USA, having far-reaching implications for the guidance of nelV age leaders engaged in developmental tasks globally.