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This paper aims to present a novel and cost-effective optical biosensor design by simple preparation method for detection of “parathion-methyl,” which is a model pesticide pose to public health and the environment.

The optical enzyme biosensor (TCA) for detection of pesticide “parathion-methyl” was developed on the basis of immobilization of tyrosinase enzyme on chitosan film by adsorption technique. The analytic performance of TCA was investigated by measuring its activity with Ultraviolet (UV) visible spectrophotometer.

Uniform porous network structure and protonated groups of chitosan film provided a microenvironment for tyrosinase immobilization evident from Fourier transform infrared (FTIR) spectroscopy and Atomic Force Microscopy analysis. TCA has a wide linear detection range (0-1.03 µM) with high correlation coefficient and it can detect the parathion-methyl concentration as low as 159 nM by noncompetitive inhibition kinetics. Using the TCA sensor both for ten times and at least 45 days without a significant loss in its activity are the indicators of its good operational and storage stability. Moreover, TCA can be applicable to tap water, providing a promising tool for pesticides detection.

This is the first time to use the in situ analytical technique that can improve the performance of optical enzyme sensor provided to control the pesticide residue better with respect to traditional techniques. The effect of organic solvents on the performance of optical enzyme biosensor was investigated. Inhibition kinetic of the solvents rarely encountered in literature was also studied besides the pH and temperature tolerance of the optical biosensor.

Investigates the assimilation and persistency of ¹⁴C‐parathion in an aqueous culture system. The radioactive pesticide was added to the nutrient medium of both soybean and wheat plants grown under aseptic and controlled conditions. Total applied radioactivity to the nutrient solution of both soybean and wheat were 1670 and 418 Bg, respectively. After 48 hours a balance sheet for the transported and recovered radioactivity was calculated. Turnover rate of the studied pesticide was concluded on the basis of its conversion to polar and non‐polar metabolites, in addition to the non‐extractable residues. Indicates that parathion has moderate persistence in the studied aqueous culture system; most of the applied radioactivity was transported from the nutrient solution and detected in the grown plants; polar metabolites were the predominant fraction in the nutrient solution as well as plant tissues; and in general, p‐nitrophenol was found in comparatively higher proportions as end product rather than paraoxon. Minor differences were evident regarding the metabolic behaviour of the pesticide under investigation in both soybean and wheat cultivating systems.

Demographic, social, epidemiologic and political changes occur simultaneously with macroeconomic changes. In the health sector, for instance, the progress evident in health status in several nations seems to correspond globally with the number of people living below sustenance level, health and nutritional requirements in the past three decades. Increasing demand for services beyond the coping competence of many non‐industrialized governments have rendered the poverty‐ridden population helpless in the face of adversity. In several of the poorest nations, the structural adjustment programme with its attendant myopic targets and constricted economic centralization has intensified demand for changes at the social and political strata. The structural adjustment rate in all sectors of public services which would create a meaningful and realizable institutional change and economic benefit for both government and people has been seriously retarded in non‐industrialized countries, especially the poor ones, in contrast to the more prosperous countries.

The succession of storms around the question of the disposal of the large quantities of corned beef called in or held up from the time of the Aberdeen Typhoid Epidemic can have done little to enhance the image of public administration. There was a profusion of statements, official and otherwise, and what seemed to be a fight between factions in the trade, with the position of the two Ministries involved none too clear; all this was thrown into a thorough ferment by political intervention by the Prime Minister himself. There can never have been anything quite like it in any branch of public health, not so much in what has been done, but in the way it was done.

Earliest localism was sited on a tree or hill or ford, crossroads or whenceways, where people assembled to talk, (Sax. witan), or trade, (Sax. staple), in eggs, fowl, fish or faggots. From such primitive beginnings many a great city has grown. Settlements and society brought changes; appointed headmen and officials, a cloak of legality, uplifted hands holding “men to witness”. Institutions tend to decay and many of these early forms passed away, but not the principle vital to the system. The parish an ecclesiastical institution, had no place until Saxons, originally heathens, became Christians and time came when Church, cottage and inn filled the lives of men, a state of localism in affairs which endured for centuries. The feudal system decayed and the vestry became the seat of local government. The novels of Thomas Hardy—and English literature boasts of no finer descriptions of life as it once was—depict this authority and the awe in which his smocked countrymen stood of “the vicar in his vestry”. The plague freed serfs and bondsmen, but events, such as the Poor Law of 1601, if anything, revived the parish as the organ of local government, but gradually secular and ecclesiastical aspects were divided and the great population explosion of the eighteenth century created necessity for subdivision of areas, which continued to serve the principle of localism however. The ballot box completed the eclipse of Church; it changed concepts of localism but not its importance in government.