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In the life cycle of the oriental fruit fly where larvae reside within fruits and adults exhibit high activity, the pupal stage occurs in the soil, closely tied to agricultural soil management. This study investigates the impact of four variables (body orientation, burial depth, soil particle size, and pH) on Bactrocera dorsalis’ physiological preferences, eclosion rates, and pupal stage duration. Notably, body orientation, burial depth, soil texture (particle size), and pH affect eclosion rates. The fruit fly demonstrates a preference for a supine position during eclosion, with average eclosion rates of 97.33%, contrasting with decreases to 78.00% in a head-down position. Soil with mixed particle sizes is detrimental to pupal eclosion, reducing the eclosion rate to 56.67%. And at a pH of 9.98, eclosion rates decrease to 16.67%. These factors significantly influence eclosion rates However, these factors do not significantly alter the duration of the pupal stage, with mean changes not exceeding one day when experimental conditions are modified. These findings suggests that soil manipulations affecting these variables could reduce eclosion rates without compromising the uniformity of adult emergence. This study provides a foundation for environmentally friendly pest control practices and addresses gaps in the pupal stage research of the oriental fruit fly. [ABSTRACT FROM AUTHOR]

Abstract In the life cycle of the oriental fruit fly where larvae reside within fruits and adults exhibit high activity, the pupal stage occurs in the soil, closely tied to agricultural soil management. This study investigates the impact of four variables (body orientation, burial depth, soil particle size, and pH) on Bactrocera dorsalis’ physiological preferences, eclosion rates, and pupal stage duration. Notably, body orientation, burial depth, soil texture (particle size), and pH affect eclosion rates. The fruit fly demonstrates a preference for a supine position during eclosion, with average eclosion rates of 97.33%, contrasting with decreases to 78.00% in a head-down position. Soil with mixed particle sizes is detrimental to pupal eclosion, reducing the eclosion rate to 56.67%. And at a pH of 9.98, eclosion rates decrease to 16.67%. These factors significantly influence eclosion rates However, these factors do not significantly alter the duration of the pupal stage, with mean changes not exceeding one day when experimental conditions are modified. These findings suggests that soil manipulations affecting these variables could reduce eclosion rates without compromising the uniformity of adult emergence. This study provides a foundation for environmentally friendly pest control practices and addresses gaps in the pupal stage research of the oriental fruit fly.

[Objectives] This study was conducted to investigate the effects of different concentrations of sodium cyclohexyl sulfamate on the growth and development of Drosophila melanogaster. [Methods] Different concentrations of sodium cyclohexyl sulfamate were added to the culture medium, and the effects of different concentrations of sodium cyclohexyl sulfamate on the development time and weight of D. melanogaster in various life stages were statistically analyzed. [Results] High concentration of sodium cyclohexyl sulfamate delayed the time of pupation and eclosion of D. melanogaster, which made D. melanogaster lose weight. The number of male D. melanogaster in the first generation was much larger than that of female individuals, which indicated that the effect of sodium cyclohexyl sulfamate on male D. melanogaster was greater than that of female individuals. In a word, high concentration of sodium cyclohexyl sulfamate significantly inhibited the growth and development of D. melanogaster. [Conclusions] This study provides some reference data for the research perspective of food additives and the safe use of sodium cyclohexyl sulfamate. [ABSTRACT FROM AUTHOR]

Vector-borne diseases are rampant across the world. Studies have been conducted to assess the impact of climatic factors on the life stages of various mosquito species. In this study, the overall effect of climatic factors such as temperature and relative humidity on the life span, survivability, development, and vectorial capacity of Aedes mosquito species has been evaluated. A literature survey was done through PubMed, Google Scholar, and Shodhganga databases using the keywords’ “Aedes”, “temperature”, and “humidity”. The search output was analyzed in terms of the impact of environmental factors on the life stages of Aedes species and it was observed that both temperature and relative humidity act as significant indicators for dengue vector propagation and virus transmission. A total of 86 research papers were selected for inclusion, and the study is divided into five criteria: (i) egg eclosion, (ii) larval development, (iii) pupal development, (iv) adult survival, and (v) vector transmission. A 95% Confidence Interval (CI) was estimated using SPSS software. Literature mining results revealed the most optimal temperatures for egg eclosion, larval development, pupal development, adult survival, and vector transmission were 24.03±3.79, 24.81±3.23, 26.18±3.96, 26.55±2.71, and 29.78±2.77, respectively. The study finds a knowledge gap regarding the impacts of relative humidity on Aedes biology. The outcomes of this work will contribute to a comprehensive understanding of the core behavioral patterns of Aedes mosquitoes under evolving climatic circumstances. Furthermore, these findings will play a pivotal role in shaping forthcoming strategies for mosquito control.

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Parasitoid elimination in Drosophila melanogaster involves special hemocytes, called lamellocytes, which encapsulate the eggs or larvae of the parasitoid wasps. The capsules are melanized, and metabolites of the melanization reaction may play a potential role in parasitoid killing. We have observed a variation in the melanization capacity of different, commonly used D. melanogaster strains, such as Canton-S, Oregon-R, and BL5905, BL6326. In this work, we aimed to clarify a possible connection between the effectiveness of capsule melanization and the success of parasitoid elimination following infection with Leptopilina parasitoid wasps. Circulating hemocytes and lamellocyte attachment were visualized by confocal and epifluorescence microscopy using indirect immunofluorescence. Expression profiles of the PPO2 and PPO3 prophenoloxidase genes, which encode key enzymes in the melanization reaction, were detected by qRT-PCR. Parasitization assays were used to analyze fly and wasp eclosion success. Active encapsulation and melanization reactions against Leptopilina boulardi were observed in the BL5905 and the BL6326 strains, though restricted to the dead supernumerary parasitoids, while fly and wasp eclosion rates were essentially the same in the four examined D. melanogaster strains. We conclude that encapsulation and melanization carried out by D. melanogaster following L. boulardi infection have no impact on survival.

Circadian clocks impose daily periodicities to behavior, physiology, and metabolism. This control is mediated by a central clock and by peripheral clocks, which are synchronized to provide the organism with a unified time through mechanisms that are not fully understood. Here, we characterized in Drosophila the cellular and molecular mechanisms involved in coupling the central clock and the peripheral clock located in the prothoracic gland (PG), which together control the circadian rhythm of emergence of adult flies. The time signal from central clock neurons is transmitted via small neuropeptide F (sNPF) to neurons that produce the neuropeptide Prothoracicotropic Hormone (PTTH), which is then translated into daily oscillations of Ca2+ concentration and PTTH levels. PTTH signaling is required at the end of metamorphosis and transmits time information to the PG through changes in the expression of the PTTH receptor tyrosine kinase (RTK), TORSO, and of ERK phosphorylation, a key component of PTTH transduction. In addition to PTTH, we demonstrate that signaling mediated by other RTKs contributes to the rhythmicity of emergence. Interestingly, the ligand to one of these receptors (Pvf2) plays an autocrine role in the PG, which may explain why both central brain and PG clocks are required for the circadian gating of emergence. Our findings show that the coupling between the central and the PG clock is unexpectedly complex and involves several RTKs that act in concert and could serve as a paradigm to understand how circadian clocks are coordinated. [ABSTRACT FROM AUTHOR]

The oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), pupates in the soil, and the average pupation depth increases with the number of concurrently pupating individuals at the same location. This study aimed to explain the density‐dependent pupation depth in B. dorsalis. Previous studies demonstrated that increasing pupation depth has the benefit of reduced parasitism and predation risk and the cost of reduced emergence success (i.e., eclosed adults in the soil fail to reach above ground). It was hypothesized that density‐dependent pupation depth is governed by density‐dependent cost. That is, emergence success of eclosed adults increases with density because the soil is more easily loosened as the number of individuals increases. Pupating larvae can reduce parasitism and predation risk by increasing pupation depth, but only those in high density can afford to pupate at deep depths due to the associated cost. To test the hypothesis, density‐dependent emergence success in B. dorsalis was examined in the laboratory. Newly pupated individuals were buried in peat moss approximately 5 cm below the surface, and the relationship between the number of buried pupae (four levels: 1, 25, 50, and 100 pupae) and their emergence success was recorded. To manipulate the difficulty of emergence, the level of peat moss compaction was also varied. Emergence success was uniformly high when peat moss was not heavily compacted regardless of the number of pupae, but the number of pupae had a positive effect on emergence success when the peat moss was heavily compacted. In addition, the timing of emergence was more synchronized in the highest density than in the lower densities. The results of this study, in combination with the previous findings, support the hypothesis. [ABSTRACT FROM AUTHOR]

Simple Summary: The developmental process, divided into four different stages (egg, larva, pupa and adult), is the main reason for their remarkable diversification and expansion of the insect group Holometabola. Advanced morphological techniques have been used to demonstrate the 3D thoracic anatomical structures of the holometalous model organism fruit fly, Drosophila melanogaster, before and after emergence, in order to uncover the transformation process of the muscles, nerves, and gut during development. Skeletal changes affect the original positions of the muscles. The muscles vary in size, not only becoming longer and broader, but also shorter and narrower. Different muscle shapes may appear during development. The number of bundles may also vary. The soft tissues in the body may fix the free ends of the growing muscles, and a strong adult skeleton likely causes the absence of some muscles and tendons. The flight muscles appear very early, probably to achieve full functionality of these very large adult-specific muscles in time. There are some differences during the same developmental period between the two sexes. Most muscles of the larvae and adults with similar attachment positions change their functions from supporting crawling to supporting flying and walking under the control of a more complex ventral nerve cord. The midguts of the larva and the adult are nearly the same. The model organism Drosophila melanogaster, as a species of Holometabola, undergoes a series of transformations during metamorphosis. To deeply understand its development, it is crucial to study its anatomy during the key developmental stages. We describe the anatomical systems of the thorax, including the endoskeleton, musculature, nervous ganglion, and digestive system, from the late pupal stage to the adult stage, based on micro-CT and 3D visualizations. The development of the endoskeleton causes original and insertional changes in muscles. Several muscles change their shape during development in a non-uniform manner with respect to both absolute and relative size; some become longer and broader, while others shorten and become narrower. Muscular shape may vary during development. The number of muscular bundles also increases or decreases. Growing muscles are probably anchored by the tissues in the stroma. Some muscles and tendons are absent in the adult stage, possibly due to the hardened sclerites. Nearly all flight muscles are present by the third day of the pupal stage, which may be due to the presence of more myofibers with enough mitochondria to support flight power. There are sexual differences in the same developmental period. In contrast to the endodermal digestive system, the functions of most thoracic muscles change in the development from the larva to the adult in order to support more complex locomotion under the control of a more structured ventral nerve cord based on the serial homology proposed herein. [ABSTRACT FROM AUTHOR]

BACKGROUND: Light stimulation at a specific wavelength triggers various responses in insects and can be used for pest control. To develop efficient and ecofriendly photophysical pest control methods, the effects of green light on locomotion, growth (molting and eclosion) and reproduction in Nilaparvata lugens (Stål) (BPH), a major rice pest, were studied. Transcriptomics and transmission electron microscopy (TEM) were used to investigate the mechanisms involved. RESULTS: BPH adults showed disrupted daily locomotion patterns following green light treatment at night and exhibited abnormal locomotion peaks. Total 6‐day locomotion of brachypterous adults was significantly greater than in the control group. The durations of growth stages 1–4 were all shorter under green light treatment than in the control, whereas the time from fourth molting to eclosion (stage 5) was significantly longer. When BPH adults under green light treatment began laying eggs, the egg hatching ratio (36.69%) was significantly lower than in the control (47.49%). Moreover, in contrast to the control, BPH molting and eclosion events tended to happen more at night. Transcriptome analysis proved that green light significantly affected the expression of genes involved in cuticular proteins, chitin deacetylase and chitinase, which are related to cuticular development. TEM observations confirmed abnormal cuticular development in nymph and adult BPHs (endocuticle, exocuticle and pore canals) under green light treatment. CONCLUSION: Green light treatment at night notably affected locomotion, growth and reproduction in BPH, thus providing a novel idea for controlling this pest. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Plant structural defenses such as trichomes exert a significant selection pressure on insect herbivores. However, whether variation in structural defense traits affects common herbivores in related plant species is less understood. Here, we examined the role of trichomes in plant–herbivore interactions in two commonly cultivated members in Cucurbitaceae: bottle gourd (Lagenaria siceraria) and cucumber (Cucumis sativa). In common garden experiments when the two species were grown together, we observed that they differed in their attractiveness to four major herbivore species (Trichoplusia ni, Acalymma vittatum, Diaphania indica, and Anasa tristis) and, consequently, their feeding behavior. We found that L. siceraria consistently harbored less herbivores, and the two lepidopteran herbivores (T. ni and D. indica) were found to take significantly longer time to commence feeding on them, a primary mode of pre-ingestive defense function of trichomes. To tease apart structural and chemical modes of defenses, we first used scanning electron microscopy to identify, quantify, and measure trichome traits including their morphology and density. We found that C. sativa has significantly lower number of trichomes compared to L. siceraria, regardless of trichome type and leaf surface. We then used artificial diet enriched with trichomes as caterpillar food and found that trichomes from these two species differentially affected growth and development of T. ni showing cascading effects of trichomes. Taken together, we show that trichomes, independent of chemical defenses, are an effective pre- and post-ingestive defense strategy against herbivores with negative consequences for their feeding, growth, and development. [ABSTRACT FROM AUTHOR]

C-type lectin X (CTL-X) plays critical roles in immune defense, cell adhesion, and developmental regulation. Here, a transmembrane CTL-X of Tribolium castaneum, TcCTL15, with multiple domains was characterized. It was highly expressed in the early and late pupae and early adults and was distributed in all examined tissues. In addition, its expression levels were significantly induced after being challenged with pathogen-associated molecular patterns (PAMPs) and bacteria. In vitro, the recombinant TcCTL15 could recognize bacteria through binding PAMPs and exhibit agglutinating activity against a narrow range of bacteria in the presence of Ca2+. RNAi-mediated TcCTL15-knockdown-larvae infected with Escherichia coli and Staphylococcus aureus showed less survival, had activated immune signaling pathways, and induced the expression of antimicrobial peptide genes. Moreover, silencing TcCTL15 caused eclosion defects by impairing ecdysone and crustacean cardioactive peptide receptors (CCAPRs). Suppression of TcCTL15 in female adults led to defects in ovary development and fecundity, accompanied by concomitant reductions in the mRNA levels of vitellogenin (TcVg) and farnesol dehydrogenase (TcFDH). These findings imply that TcCTL15 has extensive functions in developmental regulation and antibacterial immunity. Uncovering the function of TcCTL15 will enrich the understanding of CTL-X in invertebrates. Its multiple biological functions endow the potential to be an attractive target for pest control. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lifecycles: Most of the Himalayan butterflies are unknown. • Truncate Imperial: Protected, Rare, and Schedule II (WPA, 1972) species. • New larval host identified: Smilax lanceifolia. • Complete metamorphosis documented: 68 days. • Findings: Aids in the conservation of rare Himalayan butterflies. The North-East Himalayan region of the Indian subcontinent is enriched with high butterfly diversity. However, information on life history and larval host plants is still scanty for the majority of the butterflies in the region. Here we provide a detailed account of the life history of the lesser-known butterfly Truncate Imperial (Cheritrella truncipennis) from Upper-Hathidunga, Gyalshing District, Sikkim, a north-eastern state of India and part of the Himalaya biodiversity hotspot. We also provide a first account of its larval host plant Smilax lanceifolia. We conducted regular field visits in the study area to observe adult butterflies and locate the ovipositing sites. Subsequently, rearing of eggs and larva to their adulthood stage was conducted in the captive condition. The butterfly took 68 days to complete its entire life cycle (eggs to eclosion). The high survival rate of larvae indicates that captive breeding may be an alternative strategy for the conservation of Truncate Imperial. The study provides valuable information that may be required for detailed ecological studies and formulating regional conservation program. However, ex-situ efforts alone may not replicate the survival strategies needed in the wild (as natural habitats experiences various threats) and should only complement in-situ conservation approaches. [ABSTRACT FROM AUTHOR]

The model organism Drosophila melanogaster, as a species of Holometabola, undergoes a series of transformations during metamorphosis. To deeply understand its development, it is crucial to study its anatomy during the key developmental stages. We describe the anatomical systems of the thorax, including the endoskeleton, musculature, nervous ganglion, and digestive system, from the late pupal stage to the adult stage, based on micro-CT and 3D visualizations. The development of the endoskeleton causes original and insertional changes in muscles. Several muscles change their shape during development in a non-uniform manner with respect to both absolute and relative size; some become longer and broader, while others shorten and become narrower. Muscular shape may vary during development. The number of muscular bundles also increases or decreases. Growing muscles are probably anchored by the tissues in the stroma. Some muscles and tendons are absent in the adult stage, possibly due to the hardened sclerites. Nearly all flight muscles are present by the third day of the pupal stage, which may be due to the presence of more myofibers with enough mitochondria to support flight power. There are sexual differences in the same developmental period. In contrast to the endodermal digestive system, the functions of most thoracic muscles change in the development from the larva to the adult in order to support more complex locomotion under the control of a more structured ventral nerve cord based on the serial homology proposed herein.

Contexte : Soixante-huit cas confirmés en laboratoire de la maladie à coronavirus 2019 (COVID-19) (12 en Alberta, 56 en Saskatchewan) sont liés à un rassemblement dans un hôpital en Alberta du 1er au 4 juin 2020 et à une veillée funèbre et des funérailles dans une communauté des Premières Nations du nord de la Saskatchewan du 9 au 11 juin 2020. Objectif : Les objectifs étaient de fournir une description complète de l’épidémiologie de l’éclosion et de décrire les chaînes de transmission pour étayer l’hypothèse selon laquelle il y aurait eu des introductions multiples de la COVID-19 lors de la veillée funèbre et des funérailles. Méthodes : L’enquête sur les cas et la recherche des contacts ont été menées par les services de santé publique locaux en Alberta et en Saskatchewan, et l’Agence de la santé publique du Canada a effectué une analyse centralisée des cas. Une courbe épidémique et un diagramme de Gantt pour la période infectieuse ont été créés pour confirmer ou infirmer l’existence d’introductions multiples de la COVID-19 lors de la veillée funèbre et des funérailles. Résultats : Les dates de début de maladie s’échelonnaient du 31 mai au 1er juillet 2020. L’âge variait de 2 à 80 ans (âge médian = 43 ans). Cinq cas ont été hospitalisés; il n’y a pas eu de décès. Les renseignements disponibles sur l’exposition aux cas soutiennent l’hypothèse qu’il y a eu de multiples introductions de la COVID-19 lors de la veillée funèbre et des funérailles. Les autorités de santé publique de l’Alberta et de la Saskatchewan ont déclaré la fin de l’éclosion le 20 juillet 2020, soit deux périodes d’incubation (i.e. 28 jours) après l’apparition de la maladie chez le dernier cas primaire. Conclusion : Pendant les éclosions multijuridictionnelles, le partage des données, la coordination entre les autorités de la santé publique et l’analyse centralisée sont essentiels pour comprendre les événements qui ont conduit à l’éclosion et les hypothèses possibles concernant les chaînes de transmission.

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Parasitoid elimination in Drosophila melanogaster involves special hemocytes, called lamellocytes, which encapsulate the eggs or larvae of the parasitoid wasps. The capsules are melanized, and metabolites of the melanization reaction may play a potential role in parasitoid killing. We have observed a variation in the melanization capacity of different, commonly used D. melanogaster strains, such as Canton-S, Oregon-R, and BL5905, BL6326. In this work, we aimed to clarify a possible connection between the effectiveness of capsule melanization and the success of parasitoid elimination following infection with Leptopilina parasitoid wasps. Circulating hemocytes and lamellocyte attachment were visualized by confocal and epifluorescence microscopy using indirect immunofluorescence. Expression profiles of the PPO2 and PPO3 prophenoloxidase genes, which encode key enzymes in the melanization reaction, were detected by qRT-PCR. Parasitization assays were used to analyze fly and wasp eclosion success. Active encapsulation and melanization reactions against Leptopilina boulardi were observed in the BL5905 and the BL6326 strains, though restricted to the dead supernumerary parasitoids, while fly and wasp eclosion rates were essentially the same in the four examined D. melanogaster strains. We conclude that encapsulation and melanization carried out by D. melanogaster following L. boulardi infection have no impact on survival.

In recent years, the damage caused by thrips has become a key factor impacting the winter and spring production of fruits and vegetables in Hainan Province, China. This study aimed to elucidate the effects of different pupation environments on pupal development and eclosion of chilli thrips (Scirtothrips dorsalis Hood) by analyzing pupal development and eclosion of chilli thrips in an indoor environment with simulated natural soils and water content. Soil type, soil water content, and temperature substantially affected the eclosion of chilli thrips during the pupal stage. Both a low soil water content of 1% and a high soil water content of 15% were not conducive to the pupation and eclosion of chilli thrips. Moreover, the results indicated an interaction between soil type and soil water and temperature and soil water content, affecting the eclosion of chilli thrips. Chilli thrips not only pupated in soil but also completed pupation and eclosion in other soil-less environments, such as tender mango leaves, stalks, plastic mulch, and weed fabric. This study suggests that in addition to adopting pest control measures that target the canopy layer of crops, appropriate measures such as increasing soil water content can also be implemented in the ground layer to enhance the overall effectiveness of pest control., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Contexte : En avril 2021, une éclosion d’Escherichia coli (E. coli) O103 producteurs de Shiga-toxines (STEC) a été décelée chez des patients de deux hôpitaux de Victoria, en Colombie-Britannique. L’objectif de cette étude est de décrire l’enquête sur cette éclosion et de déterminer les problèmes de salubrité des aliments pour les produits à haut risque préparés pour les populations vulnérables. Méthodes : Des cas confirmés d’E. coli O103 ont été signalés à l’unité des maladies transmissibles d’Island Health. Le laboratoire provincial de santé publique a procédé au séquençage du génome entier des isolats des cas confirmés, conformément à la pratique courante pour les STEC en Colombie-Britannique. Les renseignements sur l’exposition ont été obtenus par l’entremise d’entretiens avec des cas et de l’examen des menus des hôpitaux. Les autorités sanitaires fédérales et locales ont procédé à une inspection de l’usine de transformation de la source suspecte. Résultats : Six cas confirmés d’E. coli O103 ont été décelés, tous liés par le séquençage du génome entier. La majorité des cas étaient des femmes (67 %) et l’âge médian était de 61 ans (intervalle de 24 à 87 ans). Tous les cas confirmés étaient des patients hospitalisés ou en consultation externe dans deux hôpitaux et ont été exposés à du céleri haché cru dans des sandwichs préparés fournis par les services alimentaires de l’hôpital. Un transformateur local fournissait le céleri haché exclusivement aux deux hôpitaux. L’analyse du produit chez le transformateur était peu fréquente, et le rinçage au chlore avait lieu avant le hachage. Nous croyons que la propagation de la contamination résiduelle par E. coli lors du processus de hachage, en plus des abus de température dans les hôpitaux, ont contribué à cette éclosion. Conclusion : Les légumes crus, comme le céleri, sont une source potentielle de STEC et présentent un risque pour les populations vulnérables. Les recommandations issues de cette éclosion comprennent des tests plus fréquents chez le transformateur, une révision du processus de chloration et de hachage et une révision des pratiques des services alimentaires de l’hôpital pour atténuer les abus de température.

L’expérience du Yukon concernant la maladie à coronavirus 2019 (COVID-19) a été intéressante; le territoire a mis en place avec succès des restrictions de voyage pour limiter l’importation du virus et a déployé les vaccins rapidement par rapport à la plupart des administrations canadiennes. Cependant, la première vague de COVID-19 du Yukon en juin et juillet 2021 a fait déborder le système de santé en raison de la transmission généralisée parmi les enfants non-vaccinés, les jeunes et les adultes, malgré une forte participation à la vaccination et le port du masque obligatoire. Cette expérience met en lumière l’importance du soutien continu aux programmes de vaccination publique, de l’adoption généralisée de vaccins dans les populations pédiatriques, et l’assouplissement judicieux des interventions non pharmaceutiques dans toutes les administrations canadiennes à mesure qu’elles rouvrent alors que des variants plus contagieux apparaissent.

Contexte : En mars 2021, une éclosion de maladie à coronavirus 2019 (COVID-19) a été déclarée dans un grand établissement de soins de longue durée et de séjour de courte durée en Colombie-Britannique, au Canada, bien après l’introduction du programme de vaccination dans les établissements de soins de longue durée qui a entraîné une baisse spectaculaire du nombre d’éclosions dans ce type d’établissement. L’objectif de cette étude est de fournir l’épidémiologie descriptive de cette éclosion, dans le contexte de l’immunisation partielle des résidents et du personnel de l’établissement. Méthodes : Les renseignements sur les cas ont été extraits d’un système de renseignements provincial (Panorama). L’analyse descriptive a été réalisée à l’aide de Microsoft Excel et de SAS. Les contrôles de gestion de l’éclosion comprenaient, sans s’y limiter, des tests asymptomatiques et des efforts pour augmenter la vaccination. Résultats : Vingt-six cas parmi les 241 résidents et trois cas parmi les 418 membres du personnel (correspondant à des taux d’attaque de 10 % et moins de 1 %, respectivement) ont été trouvés. Le taux d’attaque chez les résidents était considérablement plus faible que le taux d’attaque moyen pour les éclosions de COVID-19 dans les établissements de soins de longue durée avant le déploiement du vaccin. Dix-sept cas résidents étaient partiellement ou totalement immunisés. Quatre des huit cas hospitalisés et deux des trois cas décédés étaient partiellement immunisés. Dix-sept cas étaient des résidents en séjour temporaire. Les trois cas du personnel n’ont pas été vaccinés. Dix cas ont été trouvés avec des tests asymptomatiques. Conclusion : L’introduction de la vaccination dans les établissements a contribué à la baisse des taux d’attaque et à l’augmentation du nombre de cas asymptomatiques dans cette éclosion. Le dépistage des personnes asymptomatiques a permis de trouver des cas supplémentaires parmi les résidents vaccinés. Les résultats soulignent l’importance d’atteindre une couverture vaccinale élevée, y compris chez les résidents en séjour temporaire, afin de prévenir l’introduction du virus et les possibilités de transmission ultérieures non reconnues.

Contexte : Le taux d’incidence de la tuberculose chez les Premières Nations du nord de la Saskatchewan vivant dans les réserves est 1,5 fois plus élevé que la moyenne nationale. En décembre 2018, un membre de l’une de ces communautés a été diagnostiqué avec une tuberculose avec un frottis positif 4+, ce qui a déclenché une enquête sur l’éclosion. Objectifs : Décrire la réponse de la santé publique à l’enquête sur l’éclosion de tuberculose et mettre en évidence les facteurs de risque associés à la transmission de la tuberculose dans le nord de la Saskatchewan; et souligner la pertinence de l’outil de recherche des contacts basée sur les réseaux sociaux dans la gestion des éclosions. Méthodes : L’analyse descriptive comprenait les cas de tuberculose active et les cas d’infection tuberculeuse latente (ITL) liés au cas index par une recherche des contacts. Les données ont été recueillies à partir des cas de tuberculose active. Des analyses statistiques ont été effectuées et une analyse des réseaux sociaux a été réalisée en utilisant les lieux de résidence comme points de contact entre les cas. Résultats : Au total, huit cas de tuberculose active et 41 cas d’ITL ont été identifiés dans le cadre de cette éclosion entre décembre 2018 et mai 2019. La moitié des cas (4/8) étaient âgés de 25 à 34 ans, et cinq d’entre eux avaient un frottis négatif. Un tiers des personnes atteintes d’ITL étaient âgées de 15 à 24 ans, et environ la moitié d’entre elles ont obtenu un résultat positif au nouveau test cutané à la tuberculine (TCT). Les facteurs de risque couramment rapportés pour les cas de tuberculose et d’ITL étaient : la consommation d’alcool, le tabagisme, la consommation de marijuana, une infection tuberculeuse antérieure et être en situation d’itinérance. L’analyse des réseaux sociaux a indiqué une relation entre l’augmentation de la centralité du nœud et le fait de devenir un cas actif. Conclusion : La recherche en temps réel de contacts basée sur les réseaux sociaux, utilisée dans le cadre de la recherche active de cas, a été très efficace pour identifier les cas, et le soutien infirmier renforcé, les cliniques mobiles et la radiographie mobile ont bien fonctionné comme moyen de confirmer les cas et de proposer un traitement. Les éclosions de tuberculose dans les communautés des Premières Nations du nord de la Saskatchewan vivant dans les réserves sont favorisées par des facteurs propres à la population. Les efforts visant à mettre en œuvre des interventions adaptées au contexte sont primordiaux pour gérer les éclosions de tuberculose et prévenir leur transmission future.

Introducción. Orius insidiosus es un insecto omnívoro con estrategia de oviposición endófita, con preferencia de oviposición en plantas que garanticen refugio y alimento. Objetivo. Evaluar tres especies vegetales como sitio de oviposición de O. insidiosus en Phaseolus vulgaris (Fabaceae), Ipomoea batata (Convolvulaceae) y Portulaca oleracea (Portulacaceae). Materiales y métodos. El trabajo se realizó en el 2020, en el Centro de Investigación y Reproducción de Controladores Biológicos de la Universidad Nacional Autónoma de Nicaragua, León, Nicaragua. Se usaron esquejes de 15 cm de longitud de tres plantas para hembras de O. insidiosus como sustratos de oviposición: Portulaca oleracea L., Phaseolus vulgaris L., y Ipomoea batatas (L.) Lam. La unidad experimental (n= 90) consistió en esquejes tiernos de 15 cm de longitud, colocados de forma individual en tazas de polietileno, con treinta repeticiones por tratamiento, mediante la técnica de no elección. En cada esqueje se colocó una pareja de O. insidiosus. Cada 24 h se inspeccionaron los esquejes para contabilizar las posturas de huevos. Luego, los esquejes se removieron y revisaron durante cinco días para contabilizar la eclosión de las ninfas, se determinó el peso final del esqueje. Resultados. En los esquejes de P. oleracea se observaron los valores de postura más altos con 5,90 huevos/día por esqueje, seguido por L. batatas con 4,10 huevos/día y por último, P. vulgaris con 2,13 huevos/día. Se evidenció una variabilidad en la postura según el peso inicial y final. Los valores de eclosión fueron menores referentes a los de postura, P. oleracea obtuvo el mayor promedio de eclosión con cuatro individuos seguido por I. batatas con 1,5 y P. vulgaris con 0,8. Conclusiones. P. oleracea presentó mejor preferencia para O. insidiosus con respecto a postura de huevo y eclosión de ninfa. Podría validarse en campo como una estrategia de control biológico.

Azole fungicides have been essential pillars of global food security since the commercialization of triadimefon. However, the potential for fungicides to induce sublethal effects on larval development and emergence from overwintering is underresearched. We hypothesized that contact exposure to field-realistic concentrations of a broad spectrum of triazole fungicides alters the pupation and metamorphosis of crabronid wasps. Therefore, triazole fungicides shape the hymenopteran communities in agrocenoses. We applied field-realistic concentrations of three triazole fungicides, difenoconazole, penconazole, and tebuconazole, to the defecated prepupae of Pemphredon fabricii (Hymenoptera: Crabronidae). We monitored their survival, pupation, and metamorphosis into adults, including the timing of these events. All three tested triazole fungicides altered the time to the metamorphosis into adults of P. fabricii prepupae compared to the vehicle-treated controls. This effect was concentration-independent within the recommended concentration ranges for foliar applications. However, the three triazole fungicides were not associated with any significant declines in overall survival. Thus, the commonly used triazole fungicides affect the synchronization of the metamorphosis into adults with the availability of food and nesting resources of the study species. The study compounds did not affect the survival, which agrees with previous studies of other azole fungicides, which revealed effects on survival only when used in combination with other compounds. Further research should address the multiplicative effects of the triazole fungicides with other agrochemicals on the timing of the metamorphosis of bees and wasps. [ABSTRACT FROM AUTHOR]

Copyright of Ecosistemas y Recursos Agropecuarios is the property of Universidad Juarez Autonoma de Tabasco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Contexte : La glomérulonéphrite poststreptococcique (GNPS) est une affection rare à médiation immunitaire qui survient généralement chez les enfants à la suite d’une infection par le streptocoque du groupe A. La GNPS n’est pas considérée comme une maladie d’importance pour la santé publique, ou à déclaration obligatoire, au Canada. Une incidence plus élevée de GNPS a été décrite chez les populations autochtones du Canada. Il n’existe aucune directive nationale ou provinciale pour définir ou gérer les éclosions de GNPS. Objectif : Décrire une éclosion de sept cas pédiatriques de GNPS dans une collectivité éloignée des Premières Nations dans le nord-ouest de l’Ontario et la mise au point d’une stratégie d’intervention de santé publique à l’échelle de la collectivité. Méthodes : À la suite d’une revue de la littérature, une stratégie d’intervention a été établie. La stratégie consistait à dépister chez tous les enfants de la collectivité la présence d’un œdème facial ou périphérique ou de lésions cutanées, et à prescrire un traitement par antibiotiques si un tel œdème est constaté. Des définitions de cas, de contacts et d’éclosions ont également été élaborées. L’objectif de l’intervention était de rompre la chaîne de transmission d’une possible souche néphritogène de streptocoque circulant dans la communauté. Des données démographiques, cliniques et de laboratoire pertinentes ont été recueillies pour tous les cas. Résultat : Sept cas pédiatriques de GNPS se sont présentés au poste de soins infirmiers communautaire entre le 25 septembre et le 29 novembre 2017. Un dépistage des lésions cutanées à l’échelle de la collectivité a été réalisé pour 95 % des enfants de la communauté, y compris 17 contacts familiaux, ce qui a permis d’identifier le dernier des cas. Dix-neuf contacts familiaux adultes ont également été examinés. Dix contacts pédiatriques et deux contacts adultes présentant des lésions cutanées ont été traités avec une dose de pénicilline intramusculaire, et six contacts pédiatriques ont reçu de la céphalexine par voie orale. Aucun autre cas n’a été identifié à la suite de ce dépistage. Conclusion : La GNPS continue de se produire dans les populations autochtones du monde entier à des taux plus élevés que dans la population générale. En l’absence de déclaration obligatoire au Canada, le fardeau de la GNPS reste sous-estimé et pourrait nuire aux interventions de santé publique en amont et en aval. Des directives de santé publique fondées sur des données probantes sont nécessaires pour gérer les éclosions dans le contexte canadien. Le protocole d’intervention communautaire élaboré pour contenir l’éclosion de GNPS dans cette collectivité des Premières Nations peut servir de modèle pour la gestion des futures éclosions de GNPS.

Contexte : Pour maintenir le contrôle de l’épidémie de maladie à coronavirus 2019 (COVID-19) lorsque les mesures de confinement seront levées, il sera essentiel de renforcer les mesures de santé publique alternatives. En ce qui concerne la surveillance, il sera nécessaire de détecter rapidement une grande proportion de tous nouveaux cas afin de pouvoir les isoler, et retrouver et mettre en quarantaine les personnes qui y ont été exposées. Nous présentons ici une approche mathématique qui peut être utilisée pour déterminer combien d’échantillons doivent être recueillis par unité de surface et par unité de temps pour détecter de nouveaux agrégats de cas de COVID-19 à un stade suffisamment précoce pour contrôler une éclosion. Méthodes : Nous présentons une méthode de détermination de la taille de l’échantillon qui utilise une approche de pondération relative. Compte tenu du fait que les résultats du test de diagnostic de la COVID-19 provenant de sous-populations ont contribué à détecter la maladie à un niveau de prévalence seuil pour contrôler l’éclosion, il s’agissait de 1) déterminer si le nombre prévu d’échantillons hebdomadaires fournis par la surveillance actuelle des infections virales respiratoires fondée sur les soins de santé peut fournir une taille d’échantillon déjà adéquate pour détecter de nouveaux agrégats de cas de COVID-19 et, dans le cas contraire, 2) de déterminer combien d’échantillons hebdomadaires supplémentaires étaient nécessaires à partir d’un échantillonnage volontaire. Résultats : Lors d’une démonstration de notre méthode à une fréquence hebdomadaire et à l’échelle des provinces et territoires canadiens, nous avons constaté que seuls les provinces et les territoires les plus peuplés disposaient d’un nombre suffisant de dépistages provenant des visites médicales en raison de maladies respiratoires pour détecter la COVID-19 à notre niveau de prévalence cible — qui doit être suffisamment élevé pour identifier et contrôler les nouveaux agrégats de cas. En outre, la détection de la COVID-19 est plus efficace (moins d’échantillons requis) lorsque la surveillance se concentre sur l’exigence de tests de dépistage de patients symptomatiques par les services des soins de santé. Dans les populations volontaires : plus les taux de contact sont élevés, plus le niveau de prévalence attendu est élevé, et moins il faut d’échantillons pour détecter la COVID-19 à un seuil prédéterminé. Conclusion : Cette étude présente une stratégie de surveillance ciblée, combinant des échantillons de surveillance passive et active, afin de déterminer le nombre d’échantillons à recueillir par unité de surface et par unité de temps pour détecter de nouveaux agrégats de cas de COVID-19. L’objectif de cette stratégie est de permettre une détection suffisamment précoce pour contrôler une éclosion.

To accommodate growth, insects must periodically shed their exoskeletons. In Manduca sexta , Drosophila melanogaster and Tribolium castaneum , Bursicon (Burs)/ Partner of bursicon (Pburs)-LGR2 signal is an indispensable component for the proper execution of ecdysis behavior during adult eclosion. Nevertheless, the behavioral events and the roles of bursicon signaling in other insects deserve further exploration. In the current paper, we found that the pupal-adult ecdysis in Henosepilachna vigintioctomaculata could be divided into three distinct stages, preecdysis, ecdysis and postecdysis. Preecdysis behavioral sequences included abdomen twitches, dorsal-ventral contractions and air filling that function to loosen the old cuticle. Ecdysis events began with anterior-posterior contractions that gradually split the old integument along the dorsal body midline, followed by freeing of legs and mouthparts, and culminated in detachment from pupal cuticle. Postecdysis behavioral processes contained three actions: perch selection and stretching of elytra and hindwings. RNA interference for HvBurs , HvPburs or Hvrk (encoding LGR2) strongly impaired wing expansion actions, and slightly influenced preecdysis and ecdysis behaviors. The RNAi beetles failed to extend their elytra and hindwings. In addition, injected with ds rk also caused kinked femurs and tibia. Our findings establish that bursicon pathway is involved in regulation of adult eclosion behavior, especially wing expansion motor programs. Given that wings facilitate food foraging, courtship, predator avoidance, dispersal and migration, our results provide a potential target for controlling H. vigintioctomaculata. [Display omitted] • Adult eclosion can be divided into preecdysis, ecdysis and postecdysis in Henosepilachna vigintioctomaculata. • Knockdown of bursicon genes impairs wing expansion. • The RNAi beetles fail to extend their elytra and hindwings. • Bursicon way triggers wing expansion motor programs. [ABSTRACT FROM AUTHOR]

Circadian clocks are considered an evolutionary adaptation to environmental cycles, helping organisms to adapt to daily and seasonal changes. However, most studies on the evolution of circadian rhythms have been carried out in controlled laboratory conditions; hence evolution of circadian clocks and rhythms in organisms reared under the influence of naturally varying time cues is not well understood. To address this, we reared large outbred fly populations in an outdoor enclosure on our institutional grounds in Bengaluru, southern India for about 150 generations, at the same time maintaining their ancestral control populations under standard laboratory conditions. Studying their rhythms in eclosion, a vital behavior for Drosophila, in the laboratory and semi-natural environments revealed that flies reared under semi-natural conditions differed in the timing of eclosion under semi-natural conditions in a season-dependent manner from their laboratory-reared counterparts. These differences were manifested under harsh semi-natural environments but not under mild ones or in standard laboratory conditions. Further analysis revealed that this phenotype might be responsive to seasonal changes in temperature cycles which was confirmed in the laboratory with simulated light and temperature cycles that approximated semi-natural conditions. Our results highlight key intricacies on the relative impact of intensity and timing of environmental cues for predicting the timing of Drosophila eclosion under tropical naturalistic conditions. Overall, our research uncovers previously unexplored aspects of adaptive circadian timekeeping in complex natural conditions, offering valuable insight into the evolution of clocks. [ABSTRACT FROM AUTHOR]

Chilades pandava is a dangerous insect pest of Cycas spp., which seriously threatens the growth and development of Cycas plants. On the basis of previous studies, the paper summarized the behaviors of different insect states of C. pandava, such as feeding, flying, resting, mating, spawning, hatching, pupation, eclosion, etc., in order to provide a reference for effective prevention and control of C. pandava. [ABSTRACT FROM AUTHOR]

Contexte : Pendant la pandémie de maladie à coronavirus 2019 (COVID-19), l’Ontario a créé un plan de réouverture de l’économie en trois phases. Des éclosions étaient attendues à chaque phase. Une semaine après la phase deux de réouverture dans la région de l’administration provinciale de santé publique de de Kingston, Frontenac, Lennox et Addington, un cas positif a été signalé après trois semaines sans nouveau cas de COVID-19. L’objectif de ce rapport est de décrire cette éclosion de la COVID-19, déclarée dans un établissement de services personnels, et l’intervention de la santé publique pour contenir cette éclosion. Méthodes : L’enquête sur l’éclosion a porté sur tous les cas de COVID-19 survenus dans la région de Kingston, Frontenac, Lennox et Addington entre le 20 juin 2020 et le 3 juillet 2020. Des inspecteurs et des infirmières en Santé publique ont été rapidement déployés pour inspecter l’ESP. Une approche multimodale des dépistages à haut volume a impliqué des centres d’évaluation fixes, des capacités de dépistage au volant et des dépistages ciblés sur le site de l’éclosion. Les tests de dépistage ont été effectués par une amplification en chaîne par polymérase en temps réel au laboratoire local de Santé publique Ontario. Résultats : Trente-sept cas ont été liés à cette éclosion : 38 % par exposition directe à l’ESP; 32 % par contact familial; et 30 % par contact social et professionnel. Un événement de supercontamination a contribué à 38 % du total des cas. La majorité des cas se situaient dans les quintiles inférieurs ou moyens lorsque l’on analysait la difficulté matérielle. Les taux de dépistage ont été multipliés par quatre par rapport aux semaines de référence précédentes en réponse aux messages médiatiques et aux messages de Santé publique, ce qui a entraîné un faible pourcentage de positivité. Conclusion : L’interaction entre les dépistages intensifs et accessibles, la rapidité d’exécution en laboratoire, la recherche des contacts dans les 24 heures suivant l’obtention de résultats de laboratoire positifs conformément aux normes provinciales, une communication publique fréquente, les inspections rapides, l’auto-isolement et le port obligatoire du masque ont permis de stopper l’éclosion. Des inspections ou des autovérifications doivent être exigées dans tous les ESP avant la réouverture et les responsables de la gestion des éclosions doivent travailler avec les ESP pour réduire la possibilité d’événements de supercontamination.

Maintaining self-sustaining populations of zoo and aquarium collections can be challenged when natural reproduction fails within mixed-sex populations; however, reproductive success can sometimes be restored with the application of reproductive technologies. Among a population of three female and one male Zebra Sharks (Stegostoma tigrinum), production of young failed despite constant male presence with two of the females. To determine if assisted techniques could be used to rescue sexual reproduction, artificial insemination was performed in a singleton female twice over a three-year period using freshly collected semen. Hatching success for eggs laid by all three females was monitored to compare natural and artificial insemination modes. After the first insemination (December 15th, 2011), 143 yolked eggs resulted in no sexually produced offspring and four genetically-confirmed, parthenogenetic offspring. After the second insemination (September 24th, 2013), 62 yolked eggs resulted in two sexually produced offspring, 18 and 33 days after insemination, and three parthenogenetic offspring > 213 days post-insemination. For the two females housed with the male, no sexual offspring resulted. All females produced at least one hatched parthenote. This study successfully employed artificial insemination to circumvent barriers to natural reproduction in Zebra Sharks. With further development, artificial insemination represents a powerful tool that could be used for maintaining genetic diversity for animals housed in aquaria and conservation-based breeding programs for elasmobranchs.

Abstract The insect cuticle is the interface between internal homeostasis and the often harsh external environment. Cuticular hydrocarbons (CHCs) are key constituents of this hard cuticle and are associated with a variety of functions including stress response and communication. CHC production and deposition on the insect cuticle vary among natural populations and are affected by developmental temperature; however, little is known about CHC plasticity in response to the environment experienced following eclosion, during which time the insect cuticle undergoes several crucial changes. We targeted this crucial to important phase and studied post‐eclosion temperature effects on CHC profiles in two natural populations of Drosophila melanogaster. A forty‐eight hour post‐eclosion exposure to three different temperatures (18, 25, and 30°C) significantly affected CHCs in both ancestral African and more recently derived North American populations of D. melanogaster. A clear shift from shorter to longer CHCs chain length was observed with increasing temperature, and the effects of post‐eclosion temperature varied across populations and between sexes. The quantitative differences in CHCs were associated with variation in desiccation tolerance among populations. Surprisingly, we did not detect any significant differences in water loss rate between African and North American populations. Overall, our results demonstrate strong genetic and plasticity effects in CHC profiles in response to environmental temperatures experienced at the adult stage as well as associations with desiccation tolerance, which is crucial in understanding holometabolan responses to stress.

C-type lectin X (CTL-X) plays critical roles in immune defense, cell adhesion, and developmental regulation. Here, a transmembrane CTL-X of Tribolium castaneum, TcCTL15, with multiple domains was characterized. It was highly expressed in the early and late pupae and early adults and was distributed in all examined tissues. In addition, its expression levels were significantly induced after being challenged with pathogen-associated molecular patterns (PAMPs) and bacteria. In vitro, the recombinant TcCTL15 could recognize bacteria through binding PAMPs and exhibit agglutinating activity against a narrow range of bacteria in the presence of Ca2+. RNAi-mediated TcCTL15-knockdown-larvae infected with Escherichia coli and Staphylococcus aureus showed less survival, had activated immune signaling pathways, and induced the expression of antimicrobial peptide genes. Moreover, silencing TcCTL15 caused eclosion defects by impairing ecdysone and crustacean cardioactive peptide receptors (CCAPRs). Suppression of TcCTL15 in female adults led to defects in ovary development and fecundity, accompanied by concomitant reductions in the mRNA levels of vitellogenin (TcVg) and farnesol dehydrogenase (TcFDH). These findings imply that TcCTL15 has extensive functions in developmental regulation and antibacterial immunity. Uncovering the function of TcCTL15 will enrich the understanding of CTL-X in invertebrates. Its multiple biological functions endow the potential to be an attractive target for pest control.

Circadian rhythms, which are ubiquitous and adaptive, occur across all species, from microbes to humans, in which they organize and modify behavior and physiology. timeless (tim) is a canonical clock gene. The core composition of the Drosophila melanogaster endogenous circadian clock has been extensively investigated; however, in lepidopteran insects, including Bombyx mori, the mechanism is complicated and little is known regarding the participation of tim in the negative feedback loop responsible for behavioral activities. To arrive at a comprehensive understanding of the role of tim in the B. mori endogenous circadian clock, we exploited the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR‐associated protein 9 gene editing system. We attempted to elucidate the functions of tim in the circadian clock of B. mori using Bmtim mutants. The knockouts affected two circadian behavioral activities: adult emergence and embryo hatching rhythms. Quantitative real‐time polymerase chain reaction results confirmed that tim‐knockouts induced relative reductions in the expression levels, and thereby the oscillation amplitudes, of Bmper and Bmclk messenger RNAs during both the photophase and scotophase. Additionally, the daily rhythmic expression of Bmdbt was upregulated in the photophase and downregulated in the scotophase in a tim‐knockout. Our study reveals that tim is integral to the B. mori circadian clock and may be involved in regulating eclosion and hatching rhythms. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin de la Societe Zoologique de France is the property of Societe Zoologique de France and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The daily rhythm of adult emergence of holometabolous insects is one of the first circadian rhythms to be studied. In these insects, the circadian clock imposes a daily pattern of emergence by allowing or stimulating eclosion during certain windows of time and inhibiting emergence during others, a process that has been described as "gating." Although the circadian rhythm of insect emergence provided many of the key concepts of chronobiology, little progress has been made in understanding the bases of the gating process itself, although the term "gating" suggests that it is separate from the developmental process of metamorphosis. Here, we follow the progression through the final stages of Drosophila adult development with single-animal resolution and show that the circadian clock imposes a daily rhythmicity to the pattern of emergence by controlling when the insect initiates the final steps of metamorphosis itself. Circadian rhythmicity of emergence depends on the coupling between the central clock located in the brain and a peripheral clock located in the prothoracic gland (PG), an endocrine gland whose only known function is the production of the molting hormone, ecdysone. Here, we show that the clock exerts its action by regulating not the levels of ecdysone but that of its actions mediated by the ecdysone receptor. Our findings may also provide insights for understanding the mechanisms by which the daily rhythms of glucocorticoids are produced in mammals, which result from the coupling between the central clock in the suprachiasmatic nucleus and a peripheral clock located in the suprarenal gland. [ABSTRACT FROM AUTHOR]

The adaptive significance of adjusting behavioral activities to the right time of the day seems obvious. Laboratory studies implicated an important role of circadian clocks in behavioral timing and rhythmicity. Yet, recent studies on clock-mutant animals questioned this importance under more naturalistic settings, as various clock mutants showed nearly normal diel activity rhythms under seminatural zeitgeber conditions. We here report evidence that proper timing of eclosion, a vital behavior of the fruit fly Drosophila melanogaster, requires a functional molecular clock under quasi-natural conditions. In contrast to wild-type flies, period01 mutants with a defective molecular clock showed impaired rhythmicity and gating in a temperate environment even in the presence of a full complement of abiotic zeitgebers. Although period01 mutants still eclosed during a certain time window during the day, this time window was much broader and loosely defined, and rhythmicity was lower or lost as classified by various statistical measures. Moreover, peak eclosion time became more susceptible to variable day-to-day changes of light. In contrast, flies with impaired peptidergic interclock signaling (Pdf01 and han5304 PDF receptor mutants) eclosed mostly rhythmically with normal gate sizes, similar to wild-type controls. Our results suggest that the presence of natural zeitgebers is not sufficient, and a functional molecular clock is required to induce stable temporal eclosion patterns in flies under temperate conditions with considerable day-to-day variation in light intensity and temperature. Temperate zeitgebers are, however, sufficient to functionally rescue a loss of PDF-mediated clock-internal and -output signaling [ABSTRACT FROM AUTHOR]

Heritable variation in the timing of rhythmic events with respect to daily time cues gives rise to chronotypes. Despite its importance, the mechanisms (clock or non-clock) regulating chronotypes remain elusive. Using artificial laboratory selection for divergent phasing of emergence of adults from pupae, our group has derived populations of Drosophila melanogaster which are early and late chronotypes for eclosion rhythm. Several circadian rhythm characteristics of these populations have since been described. We hypothesized that our selection protocol has inadvertently resulted in selection for masking, a non-clock phenomenon, in the early chronotype due to the placement of our selection window (which includes the lights-ON transition). We designed experiments to discriminate between enhanced masking to light versus circadian clock mediated changes in determining enhanced emergence in the morning window in our early chronotypes. Using a series of phase-shift protocols, LD-DD transition, and T -cycle experiments, we find that our early chronotypes have evolved positive masking, and their apparent entrained phases are largely contributed by masking. Through skeleton T -cycle experiments, we find that in addition to the evolution of greater masking, our early chronotypes have also evolved advanced phase of entrainment. Furthermore, our study systematically outlines experimental approaches to examine relative contributions of clock versus non-clock control of an entrained behavior. Although it has previously been suggested that masking may confer an adaptive advantage to organisms, here we provide experimental evidence for the evolution of masking as a means of phasing that can complement clock control of an entrained behavior. [ABSTRACT FROM AUTHOR]

Although the pupation behavior of blowflies has been widely studied, this preliminary study was done on the vertical dispersal behavior (both ascending and descending) and fly emergence rate of third instar larvae of Chrysomya megacephala (Fabricius) to evaluate weather immature stages of blowflies survive burial and emerge out as adult. Third instar larvae of Chrysomya megacephala were placed at three different depths (5 cm, 25 cm and 45 cm) of soil under laboratory conditions to determine the impact of soil depth on the ascending and descending vertical dispersal behavior and the subsequent emergence of adults. The results of this study, although preliminary, but valuable to the field of forensic entomology because they provide new information about both ascending and descending vertical dispersal behavior of Chrysomya megacephala forensically important species of blowfly. In all the cases, maximum number of pupae recovered at the depth of 0 to 5 cm are 35.5 ± 4.5, 34 ± 1, 25 ± 5, when food was located at 5 cm, 25 cm and 45 cm depth respectively. This means that maximum no of larvae reached to the depth of 0 to 5 cm by ascending dispersal irrespective of at which depth they are placed. Paramount pupae were recovered from shallow burial depth of 0–5 cm in ascending dispersal and showed highest eclosion success i.e. 90.1% followed by 25 cm and 45 cm i.e. 71.7% and 55% respectively. While the number of pupae recovered as well as eclosion success was less in descending dispersal with an average of 62.8%, 39.25% and 33.9% at depths of 5, 25 and 45 cm respectively. This manifest if larvae disperse ascendingly, it increases their chance of survival. [ABSTRACT FROM AUTHOR]

The apple maggot fly, Rhagoletis pomonella (Walsh) (Diptera: Tephritidae), is a serious pest of apple in North America that is subject to quarantine measures to prevent its spread to currently pest-free regions, including the tropics. How the fly may survive in warmer climates is unclear. Here, we studied the effects of exposing postchill puparia to simulated temperate and tropical environmental conditions on eclosion of R. pomonella from Washington State, U.S.A. Puparia were chilled for 0–30 wk at 3°C and then held under four postchill conditions: A = 23°C, 16:8 L:D, 40% RH; B = 26°C, 12:12 L:D, 80% RH; C = 26°C, 16:8 L:D, 80% RH; and D = 23°C, 12:12 L:D, 40% RH, with B and D representing tropical conditions and A and C temperate conditions. Within each chill duration, total numbers of flies eclosed were equally high in tropical treatment B and temperate treatment C , while they were lower in treatments A and D. Mean weeks of the first eclosion in treatments B and C were earlier than in treatment D ; mean week of peak eclosion and 50% eclosion in treatments A , B , and C were earlier than in treatment D. Eclosion spans in treatments A , B , and D were generally shorter than in treatment C. Results suggest that if introduced into a humid tropical country, R. pomonella puparia from Washington State could produce adult flies, regardless of chill duration or lack of chilling during the pupal stage, but whether flies could establish there would require further study. [ABSTRACT FROM AUTHOR]

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Here, we have developed DIAMonDS (Drosophila Individual Activity Monitoring and Detection System) comprising time-lapse imaging by a charge-coupled device (CCD) flatbed scanner and Sapphire, a novel algorithm and web application. DIAMonDS automatically and sequentially identified the transition time points of multiple life cycle events such as pupariation, eclosion, and death in individual flies at high temporal resolution and on a large scale. DIAMonDS performed simultaneous multiple scans to measure individual deaths (≤1152 flies per scanner) and pupariation and eclosion timings (≤288 flies per scanner) under various chemical exposures, environmental conditions, and genetic backgrounds. DIAMonDS correctly identified 74–85% of the pupariation and eclosion events and ~ 92% of the death events within ± 10 scanning frames. This system is a powerful tool for studying the influences of genetic and environmental factors on fruit flies and efficient, high-throughput genetic and chemical screening in drug discovery.