scholarly journals Determinants of echolocation call frequency variation in the Formosan lesser horseshoe bat ( Rhinolophus monoceros )

2009 ◽  
Vol 276 (1674) ◽  
pp. 3901-3909 ◽  
Author(s):  
Shiang-Fan Chen ◽  
Gareth Jones ◽  
Stephen J. Rossiter
Keyword(s):  
Frequency Variation ◽  
Echolocation Call ◽  
Horseshoe Bat

scholarly journals Echolocation call frequency variation in horseshoe bats: molecular basis revealed by comparative transcriptomics

2020 ◽  
Vol 287 (1934) ◽  
pp. 20200875
Author(s):  
Haijian Sun ◽  
Wenli Chen ◽  
Jiaying Wang ◽  
Libiao Zhang ◽  
Stephen J. Rossiter ◽  
...  
Keyword(s):  
Genetic Basis ◽  
De Novo ◽  
Expression Profiles ◽  
Frequency Variation ◽  
Echolocation Call ◽  
Reverse Transcription Pcr ◽  
Strong Candidate ◽  
Horseshoe Bat ◽  
Candidate Loci ◽  
Horseshoe Bats

Recently diverged taxa with contrasting phenotypes offer opportunities for unravelling the genetic basis of phenotypic variation in nature. Horseshoe bats are a speciose group that exhibit a derived form of high-duty cycle echolocation in which the inner ear is finely tuned to echoes of the narrowband call frequency. Here, by focusing on three recently diverged subspecies of the intermediate horseshoe bat ( Rhinolophus affinis ) that display divergent echolocation call frequencies, we aim to identify candidate loci putatively involved in hearing frequency variation. We used de novo transcriptome sequencing of two mainland taxa ( himalayanus and macrurus ) and one island taxon ( hainanus ) to compare expression profiles of thousands of genes. By comparing taxa with divergent call frequencies (around 15 kHz difference), we identified 252 differentially expressed genes, of which six have been shown to be involved in hearing or deafness in human/mouse. To obtain further validation of these results, we applied quantitative reverse transcription–PCR to the candidate gene FBXL15 and found a broad association between the level of expression and call frequency across taxa. The genes identified here represent strong candidate loci associated with hearing frequency variation in bats.

New records of Rhinolophus beddomei Andersen, 1905 (Chiroptera: Rhinolophidae) from central peninsular region of India, including echolocation call characteristics

Mammalia ◽  
2015 ◽  
Vol 79 (3) ◽  
Author(s):  
Chelmala Srinivasulu ◽  
Bhargavi Srinivasulu ◽  
Harpreet Kaur ◽  
Tariq Ahmed Shah ◽  
Gundena Devender
Keyword(s):  
New Records ◽  
Echolocation Call ◽  
Horseshoe Bat

AbstractThe nominate subspecies of the lesser woolly horseshoe bat

The zoonotic potential of bat-borne coronaviruses

2020 ◽  
Vol 4 (4) ◽  
pp. 365-381
Author(s):  
Ny Anjara Fifi Ravelomanantsoa ◽  
Sarah Guth ◽  
Angelo Andrianiaina ◽  
Santino Andry ◽  
Anecia Gentles ◽  
...  
Keyword(s):  
Genetic Material ◽  
Field Research ◽  
Sympatric Species ◽  
Animal Origin ◽  
Mammalian Host ◽  
Past Century ◽  
The Past ◽  
Novel Host ◽  
Horseshoe Bat ◽  
Human Infections

Seven zoonoses — human infections of animal origin — have emerged from the Coronaviridae family in the past century, including three viruses responsible for significant human mortality (SARS-CoV, MERS-CoV, and SARS-CoV-2) in the past twenty years alone. These three viruses, in addition to two older CoV zoonoses (HCoV-229E and HCoV-NL63) are believed to be originally derived from wild bat reservoir species. We review the molecular biology of the bat-derived Alpha- and Betacoronavirus genera, highlighting features that contribute to their potential for cross-species emergence, including the use of well-conserved mammalian host cell machinery for cell entry and a unique capacity for adaptation to novel host environments after host switching. The adaptive capacity of coronaviruses largely results from their large genomes, which reduce the risk of deleterious mutational errors and facilitate range-expanding recombination events by offering heightened redundancy in essential genetic material. Large CoV genomes are made possible by the unique proofreading capacity encoded for their RNA-dependent polymerase. We find that bat-borne SARS-related coronaviruses in the subgenus Sarbecovirus, the source clade for SARS-CoV and SARS-CoV-2, present a particularly poignant pandemic threat, due to the extraordinary viral genetic diversity represented among several sympatric species of their horseshoe bat hosts. To date, Sarbecovirus surveillance has been almost entirely restricted to China. More vigorous field research efforts tracking the circulation of Sarbecoviruses specifically and Betacoronaviruses more generally is needed across a broader global range if we are to avoid future repeats of the COVID-19 pandemic.

Bats hibernating in underground shelters of Małe Pieniny mountains (the Carpathian Mountains, Southern Poland)

2010 ◽  
Vol 53 (1) ◽  
pp. 347-350
Author(s):  
Wojciech Gubała ◽  
Bronisław Wołoszyn
Keyword(s):  
Carpathian Mountains ◽  
Southern Poland ◽  
Number Of Species ◽  
Rhinolophus Hipposideros ◽  
Outer Carpathians ◽  
Horseshoe Bat

Bats hibernating in underground shelters of Małe Pieniny mountains (the Carpathian Mountains, Southern Poland) Six bat species were observed during winter censuses in years 2005-2009: Lesser horseshoe bat, Mouse-eared bat, Daubenton's bat, Whiskered/Brandt's bat, Northern bat and Brown long-eared bat. Rhinolophus hipposideros was most numerous (67% of all bats recorded). Largest hibernaculum on Polish side of range was mine Bania w Jarmucie, with maximum 29 bats during a single control, through the years of research number of species and individuals was increasing. Rarely seen in Outer Carpathians Eptesicus nilssonii winter roost was found in Homole Ravine Reserve.

scholarly journals Multiple Narrowband Interferences Characterization, Detection and Mitigation Using Simplified Welch Algorithm and Notch Filtering

2021 ◽  
Vol 11 (3) ◽  
pp. 1331
Author(s):  
Mohammad Hossein Same ◽  
Gabriel Gleeton ◽  
Gabriel Gandubert ◽  
Preslav Ivanov ◽  
Rene Jr Landry
Keyword(s):  
Power Spectrum ◽  
Embedded System ◽  
Radio Frequency ◽  
Satellite Communication ◽  
Signal To Noise Ratio ◽  
Center Frequency ◽  
Infinite Impulse Response ◽  
Frequency Variation ◽  
Welch Method ◽  
The Embedded System

By increasing the demand for radio frequency (RF) and access of hackers and spoofers to low price hardware and software defined radios (SDR), radio frequency interference (RFI) became a more frequent and serious problem. In order to increase the security of satellite communication (Satcom) and guarantee the quality of service (QoS) of end users, it is crucial to detect the RFI in the desired bandwidth and protect the receiver with a proper mitigation mechanism. Digital narrowband signals are so sensitive into the interference and because of their special power spectrum shape, it is hard to detect and eliminate the RFI from their bandwidth. Thus, a proper detector requires a high precision and smooth estimation of input signal power spectral density (PSD). By utilizing the presented power spectrum by the simplified Welch method, this article proposes a solid and effective algorithm that can find all necessary interference parameters in the frequency domain while targeting practical implantation for the embedded system with minimum complexity. The proposed detector can detect several multi narrowband interferences and estimate their center frequency, bandwidth, power, start, and end of each interference individually. To remove multiple interferences, a chain of several infinite impulse response (IIR) notch filters with multiplexers is proposed. To minimize damage to the original signal, the bandwidth of each notch is adjusted in a way that maximizes the received signal to noise ratio (SNR) by the receiver. Multiple carrier wave interferences (MCWI) is utilized as a jamming attack to the Digital Video Broadcasting-Satellite-Second Generation (DVB-S2) receiver and performance of a new detector and mitigation system is investigated and validated in both simulation and practical tests. Based on the obtained results, the proposed detector can detect a weak power interference down to −25 dB and track a hopping frequency interference with center frequency variation speed up to 3 kHz. Bit error ratio (BER) performance shows 3 dB improvement by utilizing new adaptive mitigation scenario compared to non-adaptive one. Finally, the protected DVB-S2 can receive the data with SNR close to the normal situation while it is under the attack of the MCWI jammer.

scholarly journals Complex Principal Component Analysis of Antarctic Ice Sheet Mass Balance

2021 ◽  
Vol 13 (3) ◽  
pp. 480
Author(s):  
Jingang Zhan ◽  
Hongling Shi ◽  
Yong Wang ◽  
Yixin Yao
Keyword(s):  
Principal Component Analysis ◽  
Ice Sheet ◽  
Low Frequency ◽  
Principal Component ◽  
Equatorial Pacific ◽  
Mass Change ◽  
Frequency Variation ◽  
Periodic Signal ◽  
Time Frequency ◽  
The Antarctic

Ice sheet changes of the Antarctic are the result of interactions among the ocean, atmosphere, and ice sheet. Studying the ice sheet mass variations helps us to understand the possible reasons for these changes. We used 164 months of Gravity Recovery and Climate Experiment (GRACE) satellite time-varying solutions to study the principal components (PCs) of the Antarctic ice sheet mass change and their time-frequency variation. This assessment was based on complex principal component analysis (CPCA) and the wavelet amplitude-period spectrum (WAPS) method to study the PCs and their time-frequency information. The CPCA results revealed the PCs that affect the ice sheet balance, and the wavelet analysis exposed the time-frequency variation of the quasi-periodic signal in each component. The results show that the first PC, which has a linear term and low-frequency signals with periods greater than five years, dominates the variation trend of ice sheet in the Antarctic. The ratio of its variance to the total variance shows that the first PC explains 83.73% of the mass change in the ice sheet. Similar low-frequency signals are also found in the meridional wind at 700 hPa in the South Pacific and the sea surface temperature anomaly (SSTA) in the equatorial Pacific, with the correlation between the low-frequency periodic signal of SSTA in the equatorial Pacific and the first PC of the ice sheet mass change in Antarctica found to be 0.73. The phase signals in the mass change of West Antarctica indicate the upstream propagation of mass loss information over time from the ocean–ice interface to the southward upslope, which mainly reflects ocean-driven factors such as enhanced ice–ocean interaction and the intrusion of warm saline water into the cavities under ice shelves associated with ice sheets which sit on retrograde slopes. Meanwhile, the phase signals in the mass change of East Antarctica indicate the downstream propagation of mass increase information from the South Pole toward Dronning Maud Land, which mainly reflects atmospheric factors such as precipitation accumulation.

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