Archives-March 2012

The present paper describes the effect of a single and an iterated use of organophosphorous insecticide chlorpyrifos on three species nitrogen fixing cyanobacteria. Treatment levels of 0.5 µg/ml-4.0 µg/ml were applied once or twice with two weeks interval. Graded concentrations higher than 2.5 µg/ml showed affect on the growth of cyanobacteria. Maximum yellowing was seen to be at 4 µg/ml in all three species. The reduction in bili protein started at 2.5 µg/ml concentration of the insecticide. Three algal species showed varying degrees of sensitivity to the insecticide. Calculated no observed effect concentration (NOEC) values after treatments were 0.021, 0.024 and 0.075mg/ml for first application and 0.17 and 0.19 and 0.064mg/ml after second application for Anabaena sp, Nostoc sp and Oscillatoria sp respectively. Normal agricultural use of chlorpyrifos (250gm/1000lit/hectare) in rice fields will likely to be toxic to these ubiquitous nitrogen fixing cyanobacteria. Low dose application 2.5 µg/ml enables growth of more tolerant cyanobacteria as biofertilizer.

The ligand 2,5-bis(phenylcarbamoyl)terephthalicacid (bpctpa) was synthesized and characterized. Novel co-ordination polymers were prepared by using ligand (bpctpa) and transition metal ions viz. Mn(II), Co(II), Ni(II), Cu(II), and Zn(II). The co-ordination polymers and parent ligand were characterized by elemental analysis, spectral studies, thermogravimetry, number-average molecular weights ( ), diffuse reflectance spectral studies and magnetic susceptibilities. The biological activity of all the samples has also been monitored against plant pathogens.

The inhibitive action of Tagetes erecta-leaves (TEL) extract on mild steel in 1M HCl has been studied using weight loss, electrochemical polarization and AC impedance measurements and The extract shows a very good inhibition in the hydrochloric acid medium and inhibition efficiency of the extract was found to vary with the extract concentration and immersion time. The maximum inhibition efficiency of 96% was obtained at 0.3%v/v concentration of the extract at 24h immersion time at room temperature. The potentiodynamic polarization data showed that the extract is of mixed type. EIS measurements showed that the dissolution process occurs under activation control. The protective film formed on the surface of mild steel by the adsorption of phytochemical constituents present in the extract was confirmed by SEM studies

Coating formulations were developed with diluent or modifiers that remained incorporated as a minority discontinuous phase. Epoxy resins were formed from a DGEBA (diglycidyl ether of bisphenol A), prepolymer (Epikote 828) and MXDA, (m-Xylylenediamine). Butyl laurate (BL) and clay (montmorillonite) were used as the modifier and the filler, respectively. The epoxy network forming systems were prepared by mixing the DGEBA with BL and/or clay and degassed, followed by addition of the MXDA and further degassing. Polymerisation kinetics during epoxy network formations were obtained using Differential Scanning Calorimetry (DSC) on samples of quenched reaction mixtures pre-reacted isothermally at 60 oC at 5 min intervals up to 1 h. The results showed a step-wise increase in Tg and conversion with time. The exothermic process in the clay-filled resins was controlled by the catalytic activity of the clay surface with the resin system.

Background: Although well-defined principals of rational antibiotic use are available, inappropriate prescribing patterns are reported worldwide. Accurate information on the usage of antimicrobials, including factors associated with and influencing their use, is valuable for improving the quality of prescription practice. In this survey study, some data about the prescribers' knowledge and attitude about antibiotic use was addressed. Method: A total of 250 questionnaires were distributed randomly to house staff physicians working in different hospitals in Khartoum state during Jan to Feb 2010. Results: 43.6% of respondents prescribed antibiotics according to guidelines, and only 59 (32.6%) refer to BNF or SNF. More than half of participants prescribed antibiotics with their trade and generic names. Ciprofloxacin is the most frequent antibiotic prescribed at different specialties. Conclusion: that a variety of complex reasons govern the attitudes of antibiotics. Inadequate recognition of the infectious agent is the main reason of irrational antibiotic prescribing. Amoxicillin is the most antibiotic prescribed empirically.

Reply to the Note of Jeremy Danning-Davies Reported Under ‘Further Comments on Khan’s So-Called ‘Equation of Trickery’

This paper is mainly concerned with the existence of mild solutions for some partial neutral functional integrodifferential equations with state-dependent delay in Banach spaces. The results are obtained by using resolvent operators and Krasnoselski-Schaefer’s type fixed point theorem.

In this study chloroform and methanol extracts of Ziziphus xylopyrus stem barks were tested for analgesic (Hot plate, Tail immersion and Acetic acid- induced writhing method) and anti-inflammatory activity (paw edema induced by carrageenan) in mice and rats, respectively. The methanolic extract in doses of 50, 100 and 200 mg/kg showed 10.91, 34.95 and 57.61 percentage of protection from writhing respectively and the percentage inhibition of paw edema at the end of four hours was 1.26, 24.05 and 35.42 respectively. In the Hot plate and Tail immersion models, methanolic extract in the above doses increased the pain threshold significantly after 30 min, 1, 2 and 3h of administration. Methanolic extract showed dose-dependent action in all the experimental models in different doses whereas chloroform extract was not able to show such remarkable significant activities.

The word “Bureaucracy” has been long applied in Iran, but its definitions and implications have been discussed in different forms. Most of its definitions are affected by individuals’ opinions and ideas and not by its real meaning. The importance is that unlike the current conception, bureaucracy in its real meaning is led to success although its improper use leads to poor performance of bureaucracy. In this article a scientific definition of bureaucracy is explained and its formation process in Iran is studied. Finally a solution is considered in order to optimum performance of bureaucracy in Iran. It seems that achieving the correct definition and adequate understanding of nature of bureaucracy are the best ways for planning and implementing a successful management with bureaucratic approach. Furthermore for coordinating bureaucracy with inside and outside environmental condition of the organization, this management method requires contingency and strategic approaches in order to apply it usefully and effectively in organizations with appropriate structures.

Life Cycle Assessment was successfully carried out on activated carbons produced from milk bush kernel shell (MB), flamboyant pod back (FB) and rice husk (RH) in order to determine their environmental burden and to assess the potential health impacts. The analysis covered the whole processes involved in producing activated carbon from the raw agricultural wastes. In this work the carbonaceous part of the agricultural wastes were carefully obtained, washed, with distilled water, dried in the oven, to remove moisture before being carbonized at 300 - 6000C. The carbonized chars were further activated with H3PO4, dried in the oven, washed with distilled water and NaHCO3 to remove any residual acid and finally dried in the oven. The solid pollutants generated in the production of activated carbon from MB, FB and RH ranged from 40.21 to 41.65%, 36.31 to 36.92%, and 15.34 to 21.55%, respectively, while the air pollutants generated in the production ranged from 11.85 to 12.15%, 11.83 to 11.94%, and 18.39 to 19.12%, respectively. Similarly, the liquid pollutants generated in the production activated carbon from MB, FB and RH ranged from 46.50 to 46.88%, 51.25 to 51.75%, 60.06 to 64.82%, respectively. Generally the order of the waste generated in the process was liquid > solid > air pollutants except for rice husk which produced more air pollutants than solid pollutants. The analysis of the solid pollutants showed that they can be recycled as fuel, thus leaving little quantity of solid wastes after process. Similarly the air and liquid pollutants generated were well contained within the acceptable environmental practice.