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The toxicity of benzothiazole derivatives obtained from 2-cyanomethyl benzothiazole against cotton leafworm Spodoptera littoralis 2nd and 4th instar larvae has been documented. The main objective of this research was to formulate two previously reported chromen derivatives and test their biological activity against cotton leafworm S. littoralis 2nd and 4th instar larvae under laboratory conditions. According to the standard method, two chromen derivatives with two distinct substituents (salicylaldehyde and 2-hydroxy-1-naphthaldehyde) were synthesized. Their physical and chemical properties were evaluated, and both were formulated as 10 and 9.5 percent dustable powder formulations. Both formulae were then evaluated in the laboratory on cotton leafworm S. littoralis 2nd and 4th instar larvae for mortality and developmental effect percentage. Formulation (F2) was more efficient than formulation (F3) in both cases and for both stages. Furthermore, when comparing the developmental effects on the 2nd and 4th instar larvae, the 4th instar larvae demonstrated marked tolerance. Both stages were unable to complete their life cycle. Histopathological analysis of samples from the affected stages was performed to assess the mode of action of these formulations on 4th instar larvae at their LC50 values. Experimental data showed that Formulation (F3) resulted in epidermal cells separated from the cuticular layer, necrosis, ruptured columnar cells with pyknotic nuclei, disrupted basement membrane, and weak epicuticle necrosis and separation. In comparison, formulation (F2) revealed a midgut with vacuoles, damaged columnar, muscle cell necrosis, and a ruined peritrophic matrix. Thus, the cotton leafworm S. littoralis could be combated with the newly prepared formulations (F2) and (F3).

Stress is an integral part of everyone's life. Stress at work is receiving increased attention in all organizations. Most managers understand stress intuitively. It is usually an emotional discomfort accompanied by feelings of not being able to cope, that one is not in control, or it may be an unease that all is not well. At the physical level, it includes loss of appetite, sleeplessness, ulcers ... On individual level, as a consequence of stress, the body's system is thrown out of balance. Excess acid is secreted in the stomach. Adrenaline appears in the blood and heart rates increase. Stress, then, is a psychophysiological phenomenon. Intense feelings and emotions are often the result of experiences we encounter within organizations. Some experiences are more stressful than others, and the same type of experience can be more stressful to one person than to another. Thus the stress potential of a situation can be defmed as a function of two elements: the situation and the individuals. Stress at work results from time pressures, work over/underload, conflict, lack of information, role ambiguity, change, priorities in work when they are not defined and many other causes. Organizationally, stress can produce declines in productivity, in motivation, in work quality, in alertness and effectiveness; and increases in mistakes, in interpersonal conflicts and turnover. Stress has proven to be a major cause for low job performance levels. The first step to combating stress is awareness. The individual should be aware of stress susceptibility in a variety of situations. With an understanding of the sources of his discomfort, the individual may examine his behavior for signs of the effects of stress (i.e. understand the causes and symptoms of stress, when they have a controlling role in their stress levels, they become able to work with that stress). There is no one made-to-order method to manage stress. If one knows that a situation will be stressful, it would be best to avoi