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831.
Bernard W.M. Wone Jaika Pathak Goggy Davidowitz 《Arthropod Structure & Development》2018,47(5):457-464
Flight muscle breakdown has been reported for many orders of insects, but the basis of this breakdown in insects with lifelong dependence on flight is less clear. Lepidopterans show such muscle changes across their lifespans, yet how this change affects the ability of these insects to complete their life cycles is not well documented. We investigated the changes in muscle function and ultrastructure of unfed aging adult hawk moths (Manduca sexta). Flight duration was examined in young, middle-aged, and advanced-aged unfed moths. After measurement of flight duration, the main flight muscle (dorsolongitudinal muscle) was collected and histologically prepared for transmission electron microscopy to compare several measurements of muscle ultrastructure among moths of different ages. Muscle function assays revealed significant positive correlations between muscle ultrastructure and flight distance that were greatest in middle-aged moths and least in young moths. In addition, changes in flight muscle ultrastructure were detected across treatment groups. The number of mitochondria in muscle cells peaked in middle-aged moths. Many wild M. sexta do not feed as adults; thus, understanding the changes in flight capacity and muscle ultrastructure in unfed moths provides a more complete understanding of the ecophysiology and resource allocation strategies of this species. 相似文献
832.
Rajaraman Barathi Ramadas Nirupama Krishnasamy Sundar Ravi Vidya Pathak Atima Devasena C. S. Swaminathan Krishnan Ganeshprasad Arunkumar Kuppuswamy Ashok Ayyappa Vedantham Srinivasan 《Molecular and cellular biochemistry》2022,477(3):977-978
Molecular and Cellular Biochemistry - 相似文献
833.
Moushumi Hazra Kirti Avishek Gopal Pathak 《International journal of phytoremediation》2015,17(9):835-840
Phytoremediation is an emerging technology that uses green plants (living machines) for removal of contaminants of concern (COC). These plant species have the potential to remove the COC, thereby restoring the original condition of soil or water environment. The present study focuses on assessing the heavy metals (COC) present in the contaminated water bodies of Ranchi city, Jharkhand, India. Phytoremedial potential of three plant species: Typha latifolia, Eichornia crassipes and Monochoria hastata were assessed in the present study. Heterogenous accumulation of metals was found in the three plant species. It was observed that the ratio of heavy metal concentration was different in different parts, i.e., shoots and roots. Positive results were also obtained for translocation factor of all species with minimum of 0.10 and maximum of 1. It was found experimentally that M. hastata has the maximum BFC for root as 4.32 and shoot as 2.70 (for Manganese). For T. latifolia, BCF of maximum was observed for root (163.5) and respective shoot 86.46 (for Iron), followed by 7.3 and 5.8 for root and shoot (for Manganese) respectively. E. crassipes was found to possess a maximum BCF of 278.6 (for Manganese and 151 (for Iron) and shoot as 142 (for Manganese) and 36.13 (for Iron). 相似文献
834.
Because of the pivotal role that the nerve enzyme, acetylcholinesterase plays in terminating nerve impulses at cholinergic synapses. Its active site, located deep inside a 20 Å gorge, is a vulnerable target of the lethal organophosphorus compounds. Potent reactivators of the intoxicated enzyme are nucleophiles, such as bispyridinium oxime that binds to the peripheral anionic site and the active site of the enzyme through suitable cation–π interactions. Atomic scale molecular dynamics and free energy calculations in explicit water are used to study unbinding pathways of two oxime drugs (Ortho‐7 and Obidoxime) from the gorge of the enzyme. The role of enzyme‐drug cation–π interactions are explored with the metadynamics simulation. The metadynamics discovered potential of mean force (PMF) of the unbinding events is refined by the umbrella sampling (US) corrections. The bidimensional free energy landscape of the metadynamics runs are further subjected to finite temperature string analysis to obtain the transition tube connecting the minima and bottlenecks of the unbinding pathway. The PMF is also obtained from US simulations using the biasing potential constructed from the transition tube and are found to be consistent with the metadynamics‐US corrected results. Although experimental structural data clearly shows analogous coordination of the two drugs inside the gorge in the bound state, the PMF of the drug trafficking along the gorge pathway point, within an equilibrium free energy context, to a multistep process that differs from one another. Routes, milestones and subtlety toward the unbinding pathway of the two oximes at finite temperature are identified. Proteins 2014; 82:1799–1818. © 2014 Wiley Periodicals, Inc. 相似文献
835.
Summary Four cultures of white rot fungi were screened for their ability to degrade lignin and carbohydrates of sugarcane bagasse and their effect on changes inin
vitro digestibility.Polyporus
hirsutus534 degraded maximum lignin and carbohydrates accompanied with the highest increase in digestibility, but increase in nutrient availability was maximum withPleurotus
sajorcaju (Z-6) due to lower dry matter loss during the process of fungal treatment. All the fungi tested exceptPolyporus
caperatus Berk. degraded lignin more selectively than the other components of sugarcane bagasse. 相似文献
836.
837.
Application of the silver-staining technique to air-dried chromosome preparations of the yellow fever mosquito, Aedes aegypti, revealed the following: 1) intensely stained pericentromeric regions in all chromosomes including the Y chromosome in spermatogonia, and during the primary and secondary spermatocytes; 2) the presence of prepachytene that were not reported earlier; 3) a nucleolus organizing region that persisted up to the late pachytene stage; and 4) rod or ring-like centrioles in pachytene and diplotene stages. In addition, varying numbers (1-4) of silver-stained, ring-like structures were observed during spermiogenesis. The exact nature and function of these ring-like structures is not understood. 相似文献
838.
839.
840.