A Two-Stage Approach to Device-Robust Acoustic Scene Classification

To improve device robustness, a highly desirable key feature of a competitive data-driven acoustic scene classification (ASC) system, a novel two-stage system based on fully convolutional neural networks (CNNs) is proposed. Our two-stage system leverages on an ad-hoc score combination based on two CNN classifiers: (i) the first CNN classifies acoustic inputs into one of three broad classes, and (ii) the second CNN classifies the same inputs into one of ten finer-grained classes. Three different CNN architectures are explored to implement the two-stage classifiers, and a frequency sub-sampling scheme is investigated. Moreover, novel data augmentation schemes for ASC are also investigated. Evaluated on DCASE 2020 Task 1a, our results show that the proposed ASC system attains a state-of-the-art accuracy on the development set, where our best system, a two-stage fusion of CNN ensembles, delivers a 81.9% average accuracy among multi-device test data, and it obtains a significant improvement on unseen devices. Finally, neural saliency analysis with class activation mapping (CAM) gives new insights on the patterns learnt by our models.Comment: Submitted to ICASSP 2021. Code available: https://github.com/MihawkHu/DCASE2020_task

Ultra-Short Pulsed Laser Manufacturing and Surface Processing of Microdevices

Ultra-short laser pulses possess many advantages for materials processing. Ultrafast laser has a significantly low thermal effect on the areas surrounding the focal point; therefore, it is a promising tool for micro- and submicro-sized precision processing. In addition, the nonlinear multiphoton absorption phenomenon of focused ultra-short pulses provides a promising method for the fabrication of various structures on transparent material, such as glass and transparent polymers. A laser direct writing process was applied in the fabrication of high-performance three-dimensional (3D) structured multilayer micro-supercapacitors (MSCs) on polymer substrates exhibiting a peak specific capacitance of 42.6 mF·cm−2 at a current density of 0.1 mA·cm−2. Furthermore, a flexible smart sensor array on a polymer substrate was fabricated for multi-flavor detection. Different surface treatments such as gold plating, reduced-graphene oxide (rGO) coating, and polyaniline (PANI) coating were accomplished for different measurement units. By applying principal component analysis (PCA), this sensing system showed a promising result for flavor detection. In addition, two-dimensional (2D) periodic metal nanostructures inside 3D glass microfluidic channels were developed by all-femtosecond-laser processing for real-time surface-enhanced Raman spectroscopy (SERS). The processing mechanisms included laser ablation, laser reduction, and laser-induced surface nano-engineering. These works demonstrate the attractive potential of ultra-short pulsed laser for surface precision manufacturing. Keywords: Ultra-short pulsed laser processing, Microdevices, Supercapacitor, Electronic tongue, Surface-enhanced Raman spectroscop

Patients with endometriosis may experience worse clinical manifestations and therapeutic outcomes during COVID-19 in western China- a case series comparative analysis

Abstract Background Endometriosis is a crippling, ongoing, chronic inflammatory condition. The management of these patients has been impacted by the current COVID-19 pandemic, which is still controversial. This study compared the clinical therapy outcomes and psychological scores between before and during- the epidemic. Method The data of patients who were diagnosed with endometriosis in the Department of Gynecology, Chongqing Traditional Chinese Medicine Hospital from January 2018 to December 2022 were collected. The patients were divided into pre- and intra-COVID groups. The treatment results and psychological status of the two groups were compared. Results A total of 1022 patients with endometriosis were enrolled, with a mean age of 33.16 ± 9.81 years and a BMI of 23.90 ± 3.04 kg/m2, of which 434 cases (434/1022, 42.5%) were in the pre-COVID group and 588 cases (588/1022, 57.5%) in the intra-COVID group. Both groups were well balanced for age, BMI, history of abdominopelvic surgery, family relationships, education level, and duration between initial diagnosis and admission. Compared to the Pre-COVID group, the intra-COVID group had a higher proportion of patients with chronic pelvic pain (297/434, 68.4% vs. 447/588, 76.0%, p = 0.007) and dysmenorrhea (249/434, 62.8% vs. 402/588, 70.0%, p < 0.001), more patients requiring surgery (93/434, 21.4% vs. 178/588, 30.3%, p = 0.002) and longer hospital stays (5.82 ± 2.24 days vs. 7.71 ± 2.15 days, p < 0.001). A total of 830 questionnaires were completed. In the Intra-COVID group, PHQ-2 (2 (2, 3) vs. 3 (2,4), p < 0.001), GAD-2 (2 (1, 2) vs. 3 (2, 3), p < 0.001), PHQ-4 (4 (3, 5) vs. 5 (4, 7), EHP-5 (20.26 ± 6.05 vs. 28.08 ± 7.95, p < 0.001) scores were higher than that in the pre-COVID group, while BRS (3.0 (2.2, 4.0) vs. 2.4 (1.8, 3.8), p = 0.470) were not significantly different. Conclusion During the COVID-19 epidemic, patients with endometriosis may have reduced visits to the hospital, more severe related symptoms, longer length of hospital stays, and worse quality of life, with the possible cause being a disturbance in hormone levels through increased anxiety and depression. This provides a valid clinical basis for optimizing the management of patients with endometriosis and for early psychological intervention during the epidemic

Mixed grazing and clipping is beneficial to ecosystem recovery but may increase potential N2O emissions in a semi-arid grassland

A more detailed understanding of the soil nitrogen (N) cycling and the associated functional microbial groups of nitrous oxide (N2O) production under different management practices is essential for adopting proper practice to achieve sustainability of grassland systems. We investigated soil inorganic N, the potential emissions of N2O, and the abundance of nitrifying and denitrifying communities in different grazing management systems, grazing intensities and topographies in a semi-arid grassland of Inner Mongolia, China. Four grazing intensities (0, 3, 6, and 9 sheep ha(-1)) were applied in two management systems (traditional grazing; and mixed grazing with clipping) in flat or sloped (3-4) blocks. Results showed that soil inorganic N, the gene abundance of amoA (ammonia monooxygenase) gene of ammonia-oxidizing archaea (AOA) and bacteria (AOB), and the narG (nitrate reductase) gene, as well as the potential rates of N2O production from nitrification (N-N2O) and denitrification (D-N2O) significantly decreased with the increase of grazing intensity, particularly in sloped plots; however the effect of increasing grazing intensity in decreasing soil inorganic N, gene abundance and potential N2O emissions was alleviated in mixed grazing and clipping system in flat plots, which resulted in greater potential N2O-emissions in mixed grazing and clipping system than in traditional grazing system. Soil moisture was found to be the controlling factor for N2O production in traditional grazing system while soil organic matter and nutrients (total N, soil NH4+ and NO3-) were most important in determining N2O production in mixed system. Our results suggest that after ten years of consistent grazing management, mixed grazing with clipping alleviated the suppressed N cycle under the traditional grazing, and changed the limiting factor for N2O production, shifting from soil moisture under traditional grazing to soil organic matter and nutrient status. The research highlights that mixed grazing with clipping can be considered as an effective management practice in alleviating a suppressed N cycle, and consequently the ecosystem recovery of this semi-arid grassland would likely be associated with an increase in N2O emissions. (C) 2017 Elsevier Ltd. All rights reserved

Mowing and topography effects on microorganisms and nitrogen transformation processes responsible for nitrous oxide emissions in semi-arid grassland of Inner Mongolia

Few studies have been done to investigate the impact of mowing on N2O emissions and the abundance of functional microbial genes, especially in sloping landscapes. This study aims to explore the impact of mowing on key N2O-producing processes under different topographical conditions in a semi-arid grassland. Soil samples were collected from a semiarid grassland ecosystem in Xilingol region, Inner Mongolia, where long-term management practices including non-mowing and mowing in flat and sloping blocks were conducted. We then determined (1) soil moisture, total carbon (TC) and nitrogen (TN), and mineral N (NH4 (+)-N and NO3 (-)-N) content; (2) the potential N2O emission from nitrification (N-N2O) and from denitrification (D-N2O) and potential N-2 emission (D-N2); and (3) the gene abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB), the narG (nitrate reductase) gene, and nosZ (nitrous oxide reductase) gene. Soil moisture and potential N2O emission from nitrification and denitrification were significantly lower in sloping than in flat conditions, whereas the TC, TN, NH4 (+)-N, NO3 (-)-N content, gene abundance of AOA, AOB, narG, and nosZ showed no difference between flat and sloping conditions. Mowing significantly decreased the gene abundance of AOA, AOB, narG in both flat and sloping areas, and significantly decreased potential N2O emissions, especially in sloping areas. The potential N2O emission was significantly lower on sloping than flat grassland. Mowing significantly decreased the potential N2O emissions, especially on sloping grassland. Our results suggest that topographical conditions should be incorporated into methods for estimating N2O emission and land management practices in semiarid grassland