The mechanism by which folate deficiency influences carcinogenesis is not well established, but a phenotype of DNA strand breaks, mutations, and chromosomal instability suggests an inability to repair DNA damage. To elucidate the mechanism by which folate deficiency influences carcinogenicity, we have analyzed the effect of folate deficiency on base excision repair (BER), the pathway responsible for repairing uracil in DNA. We observe an up-regulation in initiation of BER in liver of the folate-deficient mice, as evidenced by an increase in uracil DNA glycosylase protein (30%, p < 0.01) and activity (31%, p < 0.05). However, no up-regulation in either BER or its rate-determining enzyme, DNA polymerase ␤ (␤-pol) is observed in response to folate deficiency. Accordingly, an accumulation of repair intermediates in the form of DNA single strand breaks (37% increase, p < 0.03) is observed. These data indicate that folate deficiency alters the balance and coordination of BER by stimulating initiation without subsequently stimulating the completion of repair, resulting in a functional BER deficiency. In directly establishing that the inability to induce ␤-pol and mount a BER response when folate is deficient is causative in the accumulation of toxic repair intermediates, ␤-pol-haploinsufficient mice subjected to folate deficiency displayed additional increases in DNA single strand breaks (52% increase, p < 0.05) as well as accumulation in aldehydic DNA lesions (38% increase, p < 0.01). Since young ␤-polhaploinsufficient mice do not spontaneously exhibit increased levels of these repair intermediates, these data demonstrate that folate deficiency and ␤-pol haploinsufficiency interact to increase the accumulation of DNA damage. In addition to establishing a direct role for ␤-pol in the phenotype expressed by folate deficiency, these data are also consistent with the concept that repair of uracil and abasic sites is more efficient than repair of oxidized bases.

For sustainable and incremental growth, mankind is adopting renewable sources of energy along with storage systems. Storing surplus renewable energy in the form of hydrogen is a viable solution to meet continuous energy demands. In this paper the concept of electrochemical hydrogen storage in a solid multi-walled carbon nanotube (MWCNT) electrode integrated in a modified unitized regenerative fuel cell (URFC) is investigated. The method of solid electrode fabrication from MWCNT powder and egg white as an organic binder is disclosed. The electrochemical testing of a modified URFC with an integrated MWCNT-based hydrogen storage electrode is performed and reported. Galvanostatic charging and discharging was carried out and results analyzed to ascertain the electrochemical hydrogen storage capacity of the fabricated electrode. The electrochemical hydrogen storage capacity of the porous MWCNT electrode is found to be 2.47 wt%, which is comparable with commercially available AB5-based hydrogen storage canisters. The obtained results prove the technical feasibility of a modified URFC with an integrated MWCNT-based hydrogen storage electrode, which is the first of its kind. This is surelya step forward towards building a sustainable energy economy.

The growth and development of mankind is directly dependent on adoption of renewable energy sources. To meet the continuous demand of energy surplus energy generated can be stored in the form of hydrogen. In this paper, cyclic charging and discharging of multi walled carbon nano tube (MWCNT) electrode integrated proton battery has been discussed. A proton battery is a modified reversible polymer electrolyte membrane fuel cell (PEMFC) which has been thought of as an alternative to the lithium based batteries to store the energy. This energy storage in turn, improves the reliability of the intermittently available renewable energy sources. Actually, lithium based batteries are not pollution free, and cause water and air pollution. The analysis ascertains that maximum of 81.26 mAhg -1 can be stored while charging or electrolyser mode of proton battery and energy extracted while discharging or fuel cell mode is 1.476 mAhg -1. Total four charging and discharging cycles were carried out to assess the performance of proton battery.

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