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The susceptibility to IGRs, moulting hormone agonist, mimic (tebufenozide) and chitin synthesis inhibitors match (lufenuron) was studied in the 2 nd and 4 th larval instars of the cotton leafworm Spodoptera littoralis (Bosid). Obtained results revealed that match was the more toxic against 2 nd larval instars at sub-lethal concentrations LC 25 and LC 50 (0.3 and 0.6 ppm, respectively) than mimic (1.1 and 1.5ppm, respectively). But LC 90 level was the same in the two IGRs. With respect to 4 th larval instar, match induced the higher toxic effect at all sub lethal doses than mimic. Biochemical analysis showed that match and mimic exhibited a severe reduction in the activities of the detoxification enzymes, acid phosphatase and esterases (α and β), as compared to the control. The enzymatic activities were inhibited with the increase in the time posttreatment and also with the increase in dose. Therefore, the tested IGRs, tebufenozide and lufenuron , may be not detoxify by these enzymes.

Recent studies suggest a critical yet unexplored role for local places such as cities and communities in category research. In this study, I investigate how places, as the nexus of cultural, political, and material influences, can shape category dynamics, especially in the early phases of category emergence. I synthesize insights from category work with recent conceptualizations of places as geographically bounded spaces, imbued with meanings and material forms. I conduct an in-depth qualitative field study of the emergence and expansion of a new category, transitional micro-housing villages, also known as Tiny Home Villages, in Eugene, a mid-size city in the United States in 2011 - 2019. The study unpacks the role of nested places in triggering, enabling, and constraining actors and their work to create, legitimate, and expand a category. Specifically, I highlight the role of local material forms and how actors can mobilize local spaces, technologies, and practices to advance their goals in contested category dynamics.

The present study aimed to evaluate the biological effect of insect growth regulator flufenoxuron (Cascade) as a chitin synthesis inhibitor against 2 nd and 4 th larval instars of Spodoptera littoralis, to determine its toxicity. Effect of sublethal doses LC 25 , LC 50 and LC 90 were used to investigate the enzymatic activities. The tested IGR significantly increased the larval and pupal durations, on the other hand decrease the percentages of pupation, adult emergency, fecundity and fertility of the eggs produced by the adult progeny. The tested compound significantly induced larval mortalities, which were dose dependant.Treatments of the 2 nd and 4 th larval instars with the tested IGR induced some morphogenic abnormalities in larval, larval-pupal and pupal stages, as well as pupal-adult intermediate. Some emerged adults have various degrees of malformations. All the treated larvae as 2 nd instar showed a high sensitivity to the tested IGRs more than 4 th instars. The treated larvae in both 2 nd and 4 th larval instars with the sublethal doses LC 25 , LC 50 and LC 90 showed a significant decrease in enzyme activities of acid phosphatase and the non-specific esterases, α,β esterases at different times intervals post treatments.

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