Oligothymidylates: formation by thermal condensation of O 2 ,5'-cyclothymidine 3'-phosphate

Thermal activation of O(2),5'-cyclothymidine 3'-phosphate in solution and in the solid state led to the formation of thymidine oligonucleotides containing up to approximately 12 nucleotide units. Only the 3',5' internucleotide diester bonds were formed. This polymerization occurs without the addition of any activating agent or catalyst.     

Gas chromatographic determination of formaldehyde in maple syrup as 2,4-dinitrophenylhydrazone derivative

A procedure is presented for the quantitative extraction and determination of formaldehyde in maple sap and syrup. The method is based on the reaction between formaldehyde and 2,4-dinitrophenylhydrazine and determination of the derivative by gas chromatography. The procedure was used to evaluate formaldehyde in saps and syrups of paraformaldehyde implanted trees. Average recoveries were 101.5 +/- 5.7%. The detection limit was 0.078 mg/kg.     

Spontaneous aortic atherosclerosis in sheep.

Aortas of 334 sheep 6 months to 6 years old were stained with Sudan IV. Sudanophilic lesions resembling early fatty streaks of man were detected in 50% of these aortas. Metastatic calcification was seen in eight (2.3%) aortas.     

The in vitro antibacterial/synergistic activities of Withania somnifera extracts

The methanol, hexane and diethyl ether extracts from both leaves and roots of Withania somnifera were evaluated for the antibacterial/synergistic activity by agar plate disc-diffusion assay against Salmonella typhimurium and Escherichia coli. Different concentrations of Tibrim, a combination of rifampicin and isoniazid, were tested to find out the minimum inhibitory concentration (MIC), which came out to be 0.1 mg/ml for S. typhimurium and E. coli. From the six extracts tested, only methanol and hexane extracts of both leaves and roots were found to have potent antibacterial activity. A synergistic increase in the antibacterial effect of Tibrim was noticed when MIC of Tibrim was supplemented with these extracts.     

Rains-Asia Model Application to China: Policy Implications for Sulfur Control

China's continuing dependence on coal suggests a need for a cost-effective strategy to address SO₂ and acid rain impacts. Results of modeling studies show that although there are important transboundary aspects of acid rain in Asia, the majority of emissions and damages lie within China. This implies that intra-regional cooperation within China, and cost-effective sulfur control are paramount for limiting acid rain damages. This article discusses the costs and benefits of six primary and secondary control and policy options using the RAINS-ASIA and UR-BAT models. The local health benefits were estimated to be an order of magnitude larger than the ecosystem benefits at the regional level. All abatement options involve substantial costs, except intensive energy efficiency which is the most cost effective with the rate of return of almost 200 per dollar as compared to around 6 for the other options.     

Equilibrium and Kinetic Studies on Biosorption of Heavy Metals by Leaf Powder of Paper Mulberry (Broussonetia papyrifera)

Paper mulberry (Broussonetia papyrifera) leaf powder was used to remove heavy metal ions from aqueous solutions. The specific uptakes of Cu (II), Pb (II), and Cd (II) by the leaf powder were 43.40?±?0.2, 43.9?±?0.5, and 30.65?±?0.9 mg g^?1, respectively, when 500 mg L^?1 of the metal solutions were used. The data fitted well to the Langmuir isotherm. The process followed the pseudo-second-order kinetic equation and intraparticle diffusion played an important role in the adsorption process. On the basis of the calculated thermodynamic parameters such as standard enthalpy (??H°), entropy (??S°) and free energy change (??G°), it was inferred that the sorption process was endothermic and spontaneous in nature. The surface properties of the leaf powder (revealed by scanning electron microscopic observations) were suitable for the metal adsorption process. Energy dispersive X-ray fluorescence analysis confirmed the sequestration of the metal ions by the leaf powder. Fourier transform infrared spectroscopy implicated that different functional groups on the leaf powder were involved in the metal adsorption process. The results obtained from this study implicated that the B. papyrifera leaf powder was a good choice as a metal adsorbent. This abundantly available natural and eco-friendly biosorbent could be effectively used to develop a technology in the future.