A target guided subband filter for acoustic event detection in noisy environments using wavelet packets

This paper deals with acoustic event detection (AED), such as screams, gunshots, and explosions, in noisy environments. The main aim is to improve the detection performance under adverse conditions with a very low signal-to-noise ratio (SNR). A novel filtering method combined with an energy detector is presented. The wavelet packet transform (WPT) is first used for time-frequency representation of the acoustic signals. The proposed filter in the wavelet packet domain then uses a priori knowledge of the target event and an estimate of noise features to selectively suppress the background noise. It is in fact a content-aware band-pass filter which can automatically pass the frequency bands that are more significant in the target than in the noise. Theoretical analysis shows that the proposed filtering method is capable of enhancing the target content while suppressing the background noise for signals with a low SNR. A condition to increase the probability of correct detection is also obtained. Experiments have been carried out on a large dataset of acoustic events that are contaminated by different types of environmental noise and white noise with varying SNRs. Results show that the proposed method is more robust and better adapted to noise than ordinary energy detectors, and it can work even with an SNR as low as -15 dB. A practical system for real time processing and multi-target detection is also proposed in this work

Total Nuclear Reaction Cross Section Induced by Halo Nuclei and Stable Nuclei

We develop the method for the calculation of the total reaction cross sections induced by the halo nuclei and stable nuclei. This approach is based on the Glauber theory, which is valid for nuclear reactions at high energy. It is extended for nuclear reactions at low energy and intermediate energy by including both the quantum correction and Coulomb correction under the assumption of the effective nuclear density distribution. The calculated results of the total reaction cross section induced by stable nuclei agree well with the 30 experimental data within 10 percent accuracy.The comparison between the numerical results and the 20 experimental data for the total nuclear reaction cross section induced by the neutron halo nuclei and the proton halo nuclei indicates a satisfactory agreement after considering the halo structure of these nuclei, which implies the quite different mean fields for the nuclear reactions induced by halo nuclei and stable nuclei. The halo nucleon distributions and the root mean square radii of these nuclei can be extracted from above comparison based on the improved Glauber model, which indicate clearly the halo structures of these nuclei. Especially, it is clear to see that the medium correction of the nucleon-nucleon collision has little effect on the total reaction cross sections induced by the halo nuclei due to the very weak binding and the very extended density distribution.Comment: 15 pages,2 figures. Communucations in Theoretical Physics, (2003) in pres

Evidence of Hadronic Emission from the brightest-of-all-time GRB 221009A

Acceleration of hadrons in relativistic shocks has been long expected and invoked to model GRB high-energy photon and neutrino emissions. However, so far there has been no direct observational evidence of hadronic emission from GRBs. The B.O.A.T. ("brightest of all time") gamma-ray burst (GRB) 221009A had extreme energies (with an isotropic energy exceeding $10^{55}$ erg) and was detected in broad-band including the very-high-energy (VHE, $>100\,\rm GeV$) band up to $>10$ TeV. Here we perform a comprehensive spectral analysis of the GRB from keV to TeV energy range and perform detailed spectral and light curve modelings considering both the traditional synchrotron self-Compton process and the electromagnetic (EM) cascade process initiated by hadronic interactions by accelerated cosmic rays in the external shock. We find that the leptonic scenario alone is not adequate to account for the observations, whereas the proposed scenario with the combination of hadronic and leptonic components can well reproduce the multi-wavelength spectra and the light curve. This result reveals the existence of the accelerated hadronic component in the early afterglow of this extreme burst. According to this scenario, the observed TeV light curve should contain imprints of the prompt MeV emission.Comment: 15 pages, 4 figures, 3 tables. originally submitted version for Nature Astronom

Etimologi perkataan arkaik dalam bahasa Melayu: faktor dan kesan pewujudan kata

Peminjaman kata daripada bahasa rumpun lain telah menambahkan jumlah perbendaharaan Melayu. Pertambahan yang berlaku juga telah mewujudkan kesinoniman kata dan memberi nilai kepada penggunaan sesebuah kata. Walau bagaimanapun, peresapan kosa kata asing yang berterusan telah menyebabkan wujudnya perkataan arkaik. Pewujudan ini bukan hanya berlaku pada kosa kata asli Melayu malah terjadi pada kata yang dipinjam daripada rumpun bahasa lain. Oleh itu, kajian ini akan meneliti lima perkataan arkaik dalam bahasa Melayu dari sudut etimologi. Pemilihan data kajian dibuat berdasarkan penandaan simbol ‘ark’ yang merujuk kepada arkaik menerusi Kamus Dewan Perdana (2020). Selain itu, data terpilih juga dibuat berdasarkan kepada persamaan makna antara perkataan arkaik dengan perkataan pada masa kini. Pembuktian ini penting bagi mengenal pasti kemasukan atau penggunaan sesebuah kata dalam bahasa Melayu dan kemunculannya sebagai kata arkaik sebagaimana yang dicatatkan oleh pengkaji bahasa lain. Selain itu, faktor berlakunya fenomena ini turut dibincangkan dengan menggunakan kerangka pedoman etimologi yang dicadangkan oleh Collins (2003) yang diubah suai oleh Taufiq (2022). Hasil kajian menunjukkan bahawa kata arkaik terhasil menerusi penggantian kata yang lebih menyerlah penggunaannya dalam kalangan penutur bahasa. Selain itu, melalui penelitian kekerapan penggunaan serta kemunculannya menerusi manuskrip Melayu lama, beberapa perkataan yang dikaji juga tidak digunakan dengan meluas pada zamannya. Sekiranya terdapat dua perkataan yang sinonim, masyarakat Melayu lebih memilih perkataan yang difahami oleh masyarakat umum agar mudah untuk berkomunikasi, dan hal ini menyebabkan status perkataan yang dipinggirkan itu berubah menjadi perkataan arkaik

Etimologi Kesinoniman Kata Asing Dalam Bahasa Melayu

Artikel ini membincangkan perihal pewujudan bentuk kata yang bersinonim dalam bahasa Melayu melalui proses peminjaman kata daripada pelbagai rumpun bahasa. Penentuan dan pemilihan data terpilih dibuat berdasarkan makna dan asal usul kata yang telah dikenal pasti dalam kajian lepas yang mewujudkan bentuk bersinonim. Setiap data dipilih dipadankan dengan perkataan Melayu lain yang memiliki fitur persamaan dari sudut makna. Penelitian kata bersinonim dibuat berdasarkan pengaplikasian kerangka etimologi Collins (2003) yang telah diperkemaskan bersesuaian dengan objektif kajian ini. Penelitian dari sudut masa meliputi aspek penggunaan kata dalam bahasa Melayu turut dibincangkan. Pertembungan bahasa yang berlaku dan prestij bahasa mendorong berlakunya peminjaman kata daripada pelbagai rumpun bahasa. Fenomena yang berlaku secara tidak langsung membentuk kata yang bersinonim dengan perkataan Melayu sedia ada dan pembentukan kata bersinonim juga berlaku lebih daripada dua kata. Kajian ini juga mendapati kata bersinonim yang wujud menerusi peminjaman disebabkan oleh perubahan zaman yang mendorong pengguna bahasa meminjam bentuk kata lain yang diterima umum serta difahami oleh masyarakat setempat

Conservation and diversification of the transcriptomes of adult Paragonimus westermani and P. skrjabini

Gene Ontology term enrichment among transcript sets of interest from P. westermani and P. skrjabini. (XLSX 42 kb

Critical Role of FoxO1 in Granulosa Cell Apoptosis Caused by Oxidative Stress and Protective Effects of Grape Seed Procyanidin B2

Reactive oxygen species (ROS) are closely related to the follicular granulosa cell apoptosis. Grape seed procyanidin B2 (GSPB2) has been reported to possess potent antioxidant activity. However, the GSPB2-mediated protective effects and the underlying molecular mechanisms in granulosa cell apoptosis process remain unknown. In this study, we showed for the first time that GSPB2 treatment decreased FoxO1 protein level, improved granulosa cell viability, upregulated LC3-II protein level, and reduced granulosa cell apoptosis rate. Under a condition of oxidative stress, GSPB2 reversed FoxO1 nuclear localization and increased its level in cytoplasm. In addition, FoxO1 knockdown inhibited the protective effects of GSPB2 induced. Our findings suggest that FoxO1 plays a pivotal role in regulating autophagy in granulosa cells, GSPB2 exerts a potent and beneficial role in reducing granulosa cell apoptosis and inducing autophagy process, and targeting FoxO1 could be significant in fighting against oxidative stress-reduced female reproductive system diseases