Fracture resistance of tooth restored with four glass fiber post systems of varying surface geometries: an in vitro study

Background: The purpose of this study was to relate the fracture resistance of endodontically treated teeth in relation to post geometry. Material and Methods: Forty single rooted mandibular premolars were instrumented by step - back technique and obturated by lateral condensation. Forty teeth were randomly divided into four groups: Reforpost glass fiber X- ray®, RelyX®, Exacto conical® and Parapost Fiber Lux®. The post spaces were prepared using respective drills and luted. The core build up was done and metal crowns were luted. Fracture resistance was determined in universal testing machine. The statistical analysis was done using one way ANOVA and post hoc Tukey Kramer test. Results: The teeth restored with Reforpost showed highest fracture resistance followed by Parapost and Exacto conical. The teeth restored with RelyX showed least fracture resistance. The teeth restored with Parapost had less unfavourable fracture followed by exacto conical. Conclusions: Parallel design had less number of catastrophic failure and had better fracture resistanc

Cytotoxic and genotoxic effects of cleistanthin B in normal and tumour cells

Cleistanthin B, one of the toxic constituents of Cleistanthus collinus, was found to be cytotoxic to normal and tumour cells. In comparison with normal cells, tumour cells were sensitive to lower doses of toxin. The 50% growth inhibition (GI50) values for normal cell lines were from 2 × 10-5 to 4.7 × 10-4 M and for tumour cells the values ranged from 1.6 × l0-6 to 4 × l0-5 M. Short exposure (30 min) of Chinese hamster ovary (CHO) cells to cleistanthin B at 1-6 μg/ml resulted in extensive chromatid and isochromatid breaks and gaps. However there was no significant increase in cell death and DNA strand breaks in cells treated under the above conditions. Cleistanthin B induced micronucleus formation in cultured lymphocytes in a dose-dependent manner. CHO cells treated with high doses of cleistanthin B showed a decrease in cell viability and a concomitant increase in DNA strand-breaks. The cell death appears to be due to apoptosis since nucleosome-like ladders were observed in the treated cells when the DNA was electrophorized in agarose gels

Intraspecific varibility of corynespora cassiicola inferred from single nucleotide polymorphisms in ITS region of ribosomal DNA

Two single nucleotide polymorphisms (SNPs) were detected in the internal transcribed spacer region of the nuclear ribosomal DNA (rDNA-ITS) of 21 Corynespora cassiicola isolates obtained from a number of Hevea clones grown in rubber plantations in Malaysia. The two SNPs correlated with the physiological races of the isolates. Database searches yielded another 28 C. cassiicola isolates from diverse hosts and geographical regions. With this inclusion, a total of seven SNPs and two indels in the rDNA-ITS region were detected from all 49 C. cassiicola isolates. The knowledge of intraspecific variability (SNPs and indels) could prove useful in the delineation of physiological races or pathotypes of this fungus

Broad-basing 'green' stock market indices: a concept note

Sustainability ('green') stock market indices are intended to focus attention on environmental credentials, to reward superior performance and to help channel investments. Such indices often incorporate clean energy, waste, water and waste water treatment, recycling and other 'pure play enviro' companies. This paper contends that in keeping with the philosophy of Green Economics, which advocates an expansive view of humankind's interaction with the environment, true environmental performance ('greenness') is indexed by the eco-sensitivity of mainstream businesses, by the level of stakeholder involvement and by the extent of information readily made available to society. Effective enforcement of environmental regulation requires contributions from all stakeholders concerned. With voluntary participation from businesses not readily forthcoming, and given the price-sensitivity of consumers, investors, through the incentive structures they face, could contribute to better enforcement of regulatory standards. Broad-basing the green index could be interpreted as recognising and rewarding the superior environmental performance of mainstream businesses and/or ensuring adequate representation in emerging markets, where a large number of 'pure play enviro' related instruments are unlikely to be listed.green economics; green stock markets; stock market indices; eco-sensitive business; emerging markets; environmental goodwill; sustainability; sustainable development; environmental performance.

Segmentation of the Indian photovoltaic market

This paper provides an analytical framework studying the actors, networks and institutions and examines the evolution of the Indian Solar Photovoltaic (PV) Market. Different market segments, along the lines of demand and supply of PV equipment, i.e. on the basis of geography, end-use application, subsidy policy and other financing mechanisms, are detailed. The objective of this effort is to identify segments that require special attention from policy makers, donors and the Ministry of Non-Conventional Energy Sources. The paper also discusses the evolution of the commercial PV market in certain parts of the country and trends in the maturity of the market.Indian solar PV industry Segmentation Commercial PV markets

The Indian solar photovoltaic industry: a life cycle analysis

This paper applies the product life cycle framework to analyze the impact of global trends on the Indian photovoltaic industry. The author believes that consolidation in the Indian industry simultaneous with exploiting its comparative advantage of flexible and low cost production techniques would help it stand on its own feet beyond the protectionist subsidy era. Service provision and financing are likely to represent significant revenue opportunities while dwindling margins on module manufacture would expedite formation of vertically integrated energy service delivery chains.Indian solar PV industry Consolidation Vertical integration

Subsidy policy and the enlargement of choice

Development is the enlargement of people's choices. Optimal subsidy policy is intended to create the right incentives for each of the value chain participants. This paper contends that the interest subsidy offered by the Indian federal Ministry of New and Renewable Energy for solar thermal systems, through mainstream banking channels is superior in intent and outcome compared to the capital subsidy as currently offered for solar PV systems, routed through government controlled delivery channels. The interest subsidy enhances innovation, improves service delivery and expands the range of product available to consumers enjoying a wide range of endowments, thus leading to more inclusive development. The simple monopoly model developed by Atkinson [Atkinson AB. Capabilities, exclusion and the supply of goods. In: Basu K, Pattanaik P, Suzumura K, editor, Choice, Welfare and Development. Oxford University Press; 1995] is applied to the context of solar home systems to demonstrate price reduction and choice expansion in a liberalized market, facilitated by an interest subsidy scheme.Incentive structures Choice enlargement Solar energy systems

Microfinance for Renewable Energy: financing the 'former poor'

Microbanking facilities have helped large numbers of developing country nationals by supporting the establishment and growth of microenterprises. And yet, the microfinance movement has grown on the back of passive replication and needs to be revitalised with new product offerings and innovative service delivery. Renewable Energy systems viz., solar home systems, biogas digesters, etc., serve to improve indoor air quality, provide superior light and extend working and study hours. Such applications are not inherently income generating and returns on such investments accrue from cost avoidance, but should qualify for microfunding, as such 'quality of life' investments, reflect borrower maturity and simultaneously contribute to MFI sustainability.microfinance; MF; renewable energy; RE; microbanking; non-self-liquidating loans; quality-of-life investments; microenterprises; new product development; service delivery; solar energy; solar power; biogas; air quality; sustainability; sustainable development; product innovation.