scholarly journals Flight-tone mediated circadian control of audibility in mating swarms of Anopheles mosquitoes

2021 ◽  
Author(s):  
Jason Somers ◽  
Marcos Georgiades ◽  
Matthew P Su ◽  
Judit Bagi ◽  
Marta Andres ◽  
...  
Keyword(s):  
Circadian Clock ◽  
Detection System ◽  
Activity Patterns ◽  
Acoustic Detection ◽  
Male And Female ◽  
Anopheles Mosquitoes ◽  
Circadian Control ◽  
Harmonic Convergence ◽  
Malaria Mosquitoes

Mating swarms of malaria mosquitoes form every day at sunset throughout the tropical world, they typically last less than 30 minutes. Activity patterns must thus be highly synchronized between the sexes. Moreover, males must be able to identify the few sporadically entering females by detecting the females' faint flight tones. We here show that the Anopheles circadian clock ensures a tight synchrony of male and female activity and - importantly - also retunes the males' acoustic detection system: by lifting their own flight tones at dusk, males actively enhance the audibility of females. The reported phenomenon of 'harmonic convergence' is a random by-product of the mosquitoes' flight tone variance. Intriguingly, flight tones of individual mosquitoes occupy narrow, partly non-overlapping, frequency ranges, suggesting that the audibility of individual females varies across males.

scholarly journals Cryptochromes regulate IGF-1 production and signaling through control of JAK2-dependent STAT5B phosphorylation

2017 ◽  
Vol 28 (6) ◽  
pp. 834-842 ◽  
Author(s):  
Amol Chaudhari ◽  
Richa Gupta ◽  
Sonal Patel ◽  
Nikkhil Velingkaar ◽  
Roman Kondratov
Keyword(s):  
Circadian Rhythms ◽  
Circadian Clock ◽  
Skeletal Muscles ◽  
Cancer Metabolism ◽  
Reduced Body ◽  
Circadian Control ◽  
Cell Growth And Proliferation ◽  
Deficient Mice ◽  
Igf Signaling

Insulin-like growth factor (IGF) signaling plays an important role in cell growth and proliferation and is implicated in regulation of cancer, metabolism, and aging. Here we report that IGF-1 level in blood and IGF-1 signaling demonstrates circadian rhythms. Circadian control occurs through cryptochromes (CRYs)—transcriptional repressors and components of the circadian clock. IGF-1 rhythms are disrupted in Cry-deficient mice, and IGF-1 level is reduced by 80% in these mice, which leads to reduced IGF signaling. In agreement, Cry-deficient mice have reduced body (∼30% reduction) and organ size. Down-regulation of IGF-1 upon Cry deficiency correlates with reduced Igf-1 mRNA expression in the liver and skeletal muscles. Igf-1 transcription is regulated through growth hormone–induced, JAK2 kinase–mediated phosphorylation of transcriptional factor STAT5B. The phosphorylation of STAT5B on the JAK2-dependent Y699 site is significantly reduced in the liver and skeletal muscles of Cry-deficient mice. At the same time, phosphorylation of JAK2 kinase was not reduced upon Cry deficiency, which places CRY activity downstream from JAK2. Thus CRYs link the circadian clock and JAK-STAT signaling through control of STAT5B phosphorylation, which provides the mechanism for circadian rhythms in IGF signaling in vivo.

scholarly journals Circadian Clock Regulates Inflammation and the Development of Neurodegeneration

2021 ◽  
Vol 11 ◽  
Author(s):  
Xiao-Lan Wang ◽  
Lianjian Li
Keyword(s):  
Circadian Clock ◽  
Immune Cells ◽  
Brain Function ◽  
Cellular Tissue ◽  
Physiological Processes ◽  
Circadian Control ◽  
Prevention And Treatment ◽  
Potential Strategy ◽  
Peripheral Immune Cells

The circadian clock regulates numerous key physiological processes and maintains cellular, tissue, and systemic homeostasis. Disruption of circadian clock machinery influences key activities involved in immune response and brain function. Moreover, Immune activation has been closely linked to neurodegeneration. Here, we review the molecular clock machinery and the diurnal variation of immune activity. We summarize the circadian control of immunity in both central and peripheral immune cells, as well as the circadian regulation of brain cells that are implicated in neurodegeneration. We explore the important role of systemic inflammation on neurodegeneration. The circadian clock modulates cellular metabolism, which could be a mechanism underlying circadian control. We also discuss the circadian interventions implicated in inflammation and neurodegeneration. Targeting circadian clocks could be a potential strategy for the prevention and treatment of inflammation and neurodegenerative diseases.

scholarly journals Development and Evaluation of Real-time Acoustic Detection System of Harmful Red-tide Using Ultrasonic Sound

2013 ◽  
Vol 35 (1) ◽  
pp. 15-26 ◽  
Author(s):  
Donhyug Kang ◽  
Seonho Lim ◽  
Hyungbeen Lee ◽  
Jaewon Doh ◽  
Youn-Ho Lee ◽  
...  
Keyword(s):  
Real Time ◽  
Detection System ◽  
Red Tide ◽  
Acoustic Detection ◽  
Ultrasonic Sound

Acoustic Detection of Distressed Freight Car Roller Bearings

2007 ◽  
Author(s):  
Gerald B. Anderson
Keyword(s):  
High Risk ◽  
North America ◽  
Detection System ◽  
Roller Bearing ◽  
Acoustic Emissions ◽  
Basic Research ◽  
Acoustic Detection ◽  
Internal Damage ◽  
Increased Risk ◽  
Freight Car

Trackside Acoustic Detection System (TADS®) development spearheaded implementation of an acoustic freight car roller bearing detector whose purpose is to prevent in-service bearing failures (burned off journals and hot bearing detector train stops). The means of accomplishing this goal is by providing the user with a warning of internal bearing defects or degradation with component involvement and severity information. The Transportation Technology Center, Inc. (TTCI) began the TADS® development process in 1994 with basic research into bearing defect acoustic emissions. Subsequently, TTCI conducted prototype testing on a North American railroad, constructed and installed of several international beta test systems, and finally has sold production systems in North America and internationally. There are currently about 40 TADS® sites in operation world-wide with 2.0 or more systems scheduled for installation in 2007. The original mission for TADS® in North America was an early warning of bearing degradation to allow for scheduled maintenance, but after initial evaluation, this mission enlarged to include notification of potentially high risk bearings. The high risk bearing is defined as one with fairly large areas of internal damage and at an increased risk of overheating or failing in service. The high risk bearing has a different acoustic signature, dissimilar to that of smaller defects. This paper will outline the change in mission for this detector and describe the development of an improved capability for detecting these high risk bearings.

Activity patterns, movements and burrows of platypuses (Ornithorhynchus anatinus) in a sub-alpine Tasmanian lake

2000 ◽  
Vol 48 (6) ◽  
pp. 701 ◽  
Author(s):  
Helen M. Otley ◽  
Sarah A. Munks ◽  
Mark A. Hindell
Keyword(s):  
Adult Male ◽  
Site Selection ◽  
Activity Patterns ◽  
Predation Pressure ◽  
Water Bodies ◽  
Male And Female ◽  
Frequent Use ◽  
Ornithorhynchus Anatinus ◽  
North Western ◽  
Tracking Period

Adult male and female platypuses were radio-tracked in summer and winter at Lake Lea, north-western Tasmania. They appeared to exhibit greater diurnality, particularly during winter months, a greater degree of overland movement and more frequent use of non-earth refuge sites than do animals inhabiting mainland water bodies. Individuals foraged continuously for up to 16 h, with longer foraging bouts observed during the winter tracking period. Foraging range varied between 2 and 58 ha, with no significant differences observed between the sexes or seasons. All platypuses foraged predominantly in the lake; however, a number of animals were observed moving overland to and from waterbodies and burrows. Burrows were located on lake, creek and pool edges. A high percentage of burrows (25%) were located within dense sedge tussocks and scrub vegetation. Both the terrestrial activity and more opportunistic burrow-site selection may be related to reduced predation pressure in Tasmania.

High bandwidth airborne acoustic detection system (HBADS) for circular synthetic aperture acoustic imaging of canonical ground targets

2019 ◽  
Vol 146 (4) ◽  
pp. 3079-3079
Author(s):  
Steven S. Bishop ◽  
Timothy R. Moore ◽  
Peter Gugino ◽  
Brett Smith ◽  
Kathryn P. Kirkwood ◽  
...  
Keyword(s):  
Detection System ◽  
Acoustic Imaging ◽  
Synthetic Aperture ◽  
Acoustic Detection ◽  
High Bandwidth

scholarly journals C-type lectins CTL4 and CTLMA2: conserved heterodimeric structure and glycan specificity in Anopheles mosquitoes

2019 ◽  
Author(s):  
Ritika Bishnoi ◽  
Alicia Contet ◽  
Christopher J Day ◽  
David Chun-Feng Hou ◽  
Lauren A. Profitt ◽  
...  
Keyword(s):  
Biochemical Characterization ◽  
Scattering Data ◽  
Connective Tissues ◽  
Anopheles Mosquitoes ◽  
Molecular Features ◽  
X Ray Scattering ◽  
Specific Variation ◽  
Malaria Mosquitoes

AbstractThe C-type lectins CTL4 and CTLMA2 cooperatively influence Plasmodium infection in the malaria vector Anopheles. Here we report the purification and biochemical characterization of CTL4 and CTLMA2 from An. gambiae and An. albimanus. CTL4 and CTLMA2 are known to form a disulfide-bridged heterodimer via an N-terminal tri-cysteine CXCPC motif. We demonstrate in vitro that CTL4 and CTLMA2 intermolecular disulfide formation is promiscuous within this motif. Furthermore, CTL4 and CTLMA2 exhibit charge complementarity that promotes the formation of higher oligomeric states at physiological pH. Both lectins bind specific sugars, with an apparent preference for glycosaminoglycan motifs comprising β1-3/β1-4 linkages between glucose (Glc), galactose (Gal) and their respective hexosamines. Small-angle x-ray scattering data supports a compact heterodimer between the CTL domains. Recombinant CTL4/CTLMA2 is functional in vivo, reversing the enhancement of phenoloxidase activity in dsCTL4-treated mosquitoes. We propose these molecular features underline a common function for CTL4/CTLMA2 in mosquitoes, with species and strain-specific variation in degrees of activity in response to Plasmodium infection.Author SummaryMosquitoes of the genus Anopheles are vectors for the single-celled parasite Plasmodium, the causative agent of malaria. Mosquitoes, like all insects, utilize the process of melanization for both wound healing and defense against pathogens. CTL4 and CTLMA2 are two proteins found in Anopheles mosquitoes that act as inhibitors of melanization, so understanding their molecular function is important to understanding the immune response of Anopheles mosquitoes to Plasmodium infection. We have purified CTL4 and CTLMA2 from two species of Anopheles and studied their molecular properties with a variety of biochemical and biophysical techniques. We also verified that our purified protein is functional by injecting it into mosquitoes. We learned that CTL4 and CTLMA2 are joined together by a disulfide bond between any one of three cysteine residues near the N-terminus of each protein. The CTL4/CTLMA2 complex is compact, but can associate into larger structures in solution, probably because of a loop in each protein that carries an opposite charge. The proteins cooperatively bind calcium and sugars, specifically glycosaminoglycan sugars, which are typically present in the connective tissues of insects. This information will aid in further investigations of the function of CTL4 and CTLMA2.

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