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Viruses, bacteria, fungus, protozoans, and different metazoan parasites and parasitoids present a constant threat to insects. Insect immunity has two components: humoral and cell mediated. Humoral immunity can be achieved by various antimicrobial proteins, namely, cecropins, sarcotoxin, defensin, attacin, etc. The cell‐mediated immunity comprises various cells having immune functions fostering nodulation, phagocytosis, microaggregation, encapsulation etc. Eicosanoids play a crucial role in insect immunity comparable to other animals. The above‐mentioned are signaling molecules derived from polyunsaturated fatty acids and they exert numerous physiological effects, namely, inflammation, immune modulation, and regulation of cellular processes. The review article elucidates various roles of eicosanoids, namely, nodulation reaction, Toll signaling pathway, nitric oxide (NO) generation, Ca2+ mobilization, production of reactive oxygen species (ROS), actin polymerization and aquaporin activation. Eicosanoids can function in immune priming in insects drawing hemocytes. An agent named Duox was also identified serving as ROS generator in insect gut. Moreover, role of Repat gene in insect immunity was also studied. However, recently the role of prostacyclin (PGI2) was found to be negative as it inhibits platelet aggregation. In this brief review, we have tried to shed light on the various functions of eicosanoids in immunity of insect those have been discovered recently. This concise study will allow to decipher eicosanoids’ function in insect immunity in a nutshell, and it will pave the way for more researches to understand the key players of insect immunity which may eventually help to develop novel vector and pest control strategies in near future. [ABSTRACT FROM AUTHOR]

Five new species of biting midges, Dasyhelea (Dasyhelea) incisura sp. nov., D. (D.) quasifulcillata sp. nov., D. (D.) trigona sp. nov., D. (Sebessia) falxa sp. nov. and D. (S.) folia sp. nov. are described and illustrated based on adult males. The new species are compared and contrasted to their congeners; important morphological characters are displayed. All specimens were collected from the Deltaic Proper of Gangetic West Bengal, India. An illustrated key to the adult males of the subgenera Dasyhelea s.str. and Sebessia from India is presented. Short accounts on ecological notes of the midges are also provided. [ABSTRACT FROM AUTHOR]

We develop a daily composite index of financial stress for the United Kingdom over 50 years, the UKFSI. The index includes market stress indicators based on their incremental information to capture financial crises. During the COVID‐19 crisis, financial stress peaks but remains less severe than during the Global Financial Crisis. The UKFSI is used in a threshold vector autoregression to differentiate the economic dynamics between tranquil and stressful periods. We highlight the importance of nonlinearities that amplify shocks. But we find no evidence of financial shocks contributing to the COVID‐19 crisis, possibly reflecting effective policy interventions. [ABSTRACT FROM AUTHOR]