Cross-layer similarity knowledge distillation for speech enhancement

Speech enhancement (SE) algorithms based on deep neural networks (DNNs) often encounter challenges of limited hardware resources or strict latency requirements when deployed in real-world scenarios. However, a strong enhancement effect typically requires a large DNN. In this paper, a knowledge distillation framework for SE is proposed to compress the DNN model. We study the strategy of cross-layer connection paths, which fuses multi-level information from the teacher and transfers it to the student. To adapt to the SE task, we propose a frame-level similarity distillation loss. We apply this method to the deep complex convolution recurrent network (DCCRN) and make targeted adjustments. Experimental results show that the proposed method considerably improves the enhancement effect of the compressed DNN and outperforms other distillation methods

Orbital Origin of Extremely Anisotropic Superconducting Gap in Nematic Phase of FeSe Superconductor

The iron-based superconductors are characterized by multiple-orbital physics where all the five Fe 3$d$ orbitals get involved. The multiple-orbital nature gives rise to various novel phenomena like orbital-selective Mott transition, nematicity and orbital fluctuation that provide a new route for realizing superconductivity. The complexity of multiple-orbital also asks to disentangle the relationship between orbital, spin and nematicity, and to identify dominant orbital ingredients that dictate superconductivity. The bulk FeSe superconductor provides an ideal platform to address these issues because of its simple crystal structure and unique coexistence of superconductivity and nematicity. However, the orbital nature of the low energy electronic excitations and its relation to the superconducting gap remain controversial. Here we report direct observation of highly anisotropic Fermi surface and extremely anisotropic superconducting gap in the nematic state of FeSe superconductor by high resolution laser-based angle-resolved photoemission measurements. We find that the low energy excitations of the entire hole pocket at the Brillouin zone center are dominated by the single $d_{xz}$ orbital. The superconducting gap exhibits an anti-correlation relation with the $d_{xz}$ spectral weight near the Fermi level, i.e., the gap size minimum (maximum) corresponds to the maximum (minimum) of the $d_{xz}$ spectral weight along the Fermi surface. These observations provide new insights in understanding the orbital origin of the extremely anisotropic superconducting gap in FeSe superconductor and the relation between nematicity and superconductivity in the iron-based superconductors.Comment: 19 pages, 4 figure

Aroylhydrazone Diorganotin Complexes Causes DNA Damage and Apoptotic Cell Death: From Chemical Synthesis to Biochemical Effects

Under microwave irradiation, eighteen new aroylhydrazone diorganotin complexes (1a–9b) were produced through the reaction of aroylhydrazine, 2-ketobutyric acid, and the corresponding diorganotin. Fourier transform infrared spectroscopy, 1H, 13C, and 119Sn nuclear magnetic resonance spectroscopies, high-resolution mass spectroscopy, X-ray crystallography, and thermogravimetric analysis (TGA) were performed to characterize the complexes. The in vitro anticancer activity for complexes were assessed using a CCK-8 assay on human cancer cells of HepG2, NCI-H460, and MCF-7. Complex 4b revealed more intensive anticancer activity against MCF-7 cells than the other complexes and cisplatin. Flow cytometry analysis and transmission electron microscope observation demonstrated that complex 4b mediated cell apoptosis of MCF-7 cells and arrested cell cycle in S phase. Western blotting analysis showed that 4b induced DNA damage in MCF-7 cells and led to apoptosis by the ATM-CHK2-p53 pathway. The single cell gel electrophoreses assay results showed that 4b induced DNA damage. The DNA binding activity of 4b was studied by UV–Visible absorption spectrometry, fluorescence competitive, viscosity measurements, gel electrophoresis, and molecular docking, and the results show that 4b can be well embedded in the groove and cleave DNA

Exploring Crowd Travel Demands Based on the Characteristics of Spatiotemporal Interaction between Urban Functional Zones

As a hot research topic in urban geography, spatiotemporal interaction analysis has been used to detect the hotspot mobility patterns of crowds and urban structures based on the origin-destination (OD) flow data, which provide useful information for urban planning and traffic management applications. However, existing methods mainly focus on the detection of explicit spatial interaction patterns (such as spatial flow clusters) in OD flow data, with less attention to the discovery of underlying crowd travel demands. Therefore, this paper proposes a framework to discover the crowd travel demands by associating the dynamic spatiotemporal interaction patterns and the contextual semantic features of the geographical environment. With urban functional zones (UFZs) as the basic units of human mobility in urban spaces, this paper gives a case study in Wuhan, China, to detect and interpret the human mobility patterns based on the characteristics of spatiotemporal interaction between UFZs. Firstly, we build the spatiotemporal interaction matrix based on the OD flows of different UFZs and analyze the characteristics of the interaction matrix. Then, hotspot poles, defined as the local areas where people gather significantly, are extracted using the Gi-statistic-based spatial hotspot detection algorithm. Next, we develop a frequent interaction pattern mining method to detect the frequent interaction patterns of the hotspot poles. Finally, based on the detected frequent interaction patterns, we discover the travel demands of crowds with semantic features of corresponding urban functional zones. The characteristics of crowd travel distance and travel time are further discussed. Experiments with floating car data, road networks, and POIs in Wuhan were conducted, and results show that the underlying travel demands can be better discovered and interpreted by the proposed framework and methods in this paper. This study helps to understand the characteristics of human movement and can provide support for applications such as urban planning and facility optimization

Investigation on Microstructures and Mechanical Properties of the Hypoeutectic Al-10Si-0.8Fe-XEr Alloy

In this paper, the effect of Er addition (0.2, 0.5, 0.65, 0.8, 1.0, and 1.5 wt. %) on the microstructure evolution and tensile properties of as-cast hypereutectic Al-10Si-0.8Fe alloy was investigated. The phases and their morphologies in these alloys were identified by XRD and SEM equipped with EDX with the help of metallographic analysis techniques; the length of the secondary phase (LSP) and secondary dendrite arm spacing (SDAS) of α-Al grain were quantified. The results indicated that the second phases (primary Si, eutectic Si, and iron-rich phases) and α-Al grain were significantly refined when the addition of Er increased from 0 to 0.8 wt. %. The mean LSP and SADS values were decreased to a minimum value when the Er addition reached 0.8 wt. %. However, the second phases and α-Al grain became coarser when the level of Er increased more than 0.8 wt. %. The analysis of XRD shows that Er mainly exists in the form of Er2Si compound. The microstructure modification also has a significant effect on the mechanical properties of the alloy. The yield strength (YS), ultimate tensile strength (UTS), and elongation (EL) increase from 52.86 MPa, 163.84 MPa, and 3.45% to 71.01 MPa, 163.84 MPa, and 5.65%, respectively. From the fracture surface, the promotions of mechanical properties are due to the dispersion and pinning reinforcement caused by the Er2Si phase

Rhodium-Catalyzed Regioselective Ortho-Allylation of 2,4-Diarylquinazolines with Allylic Acetate

In this paper, a rhodium-catalyzed high regioselective reaction of 2,4-diarylquinazolines with allylic acetate is described, leading to allylated quinazoline derivatives with high efficiency and good tolerance of functional groups. By switching to 2-arylquinazolin-4-ones, tandem C-H activation and aza-Michael addition are involved, leading to 1,6-dimethyl-5H-isoquinolino[1,2-b]quinazolin-8(6H)-one derivatives with high efficiency.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Study on Nanomaterials with Inhibitory Effects on the Growth of <i>Aspergillus niger</i>

In this paper, the inhibitory effect of various nanomaterials on the growth of Aspergillus niger was studied. Among them, copper nanorods had the most obvious inhibitory effect on the growth of Aspergillus niger. The phase of copper nanorods was modified by chitosan, and its inhibitory effect on the expansion of Aspergillus niger was measured. 1. Preparation of copper nanorods and chitosan@copper nanorods: Copper nanorods with a diameter of about 300–350 nm and a length of about 100–800 nm were prepared by the liquid-phase reduction method. The chitosan solution was prepared by using the characteristics of chitosan dissolved in dilute acid to prepare chitosan@copper nanorods and modify the phase of copper nanorods. 2. Determination of the inhibitory effect of various copper nanomaterials on the growth of Aspergillus niger, including Cuprous Oxide nanoparticles, copper nanorods, nano copper oxide, and copper hydroxide, which have certain inhibitory effects on the growth of Aspergillus niger. Among them, copper nanorods have a better effect. On this basis, chitosan@copper nanorods are obtained by modifying the phase of copper nanorods with chitosan. The measured antibacterial effect is that the EC50 value is 344 mg/L

Hydroxyapatite Whisker Reinforced 63s Glass Scaffolds for Bone Tissue Engineering

Bioactive glass (BG) is widely used for bone tissue engineering. However, poor mechanical properties are the major shortcomings. In the study, hydroxyapatite nanowhisker (HANw) was used as a reinforcement to improve the mechanical properties. 63s glass/HANw scaffolds were successfully fabricated by selective laser sintering (SLS). It was found that the optimal compressive strength and fracture toughness were achieved when 10 wt.% HANw was added. This led to 36% increase in compressive strength and 83% increase in fracture toughness, respectively, compared with pure 63s glass scaffolds. Different reinforcement mechanisms were analyzed based on the microstructure investigation. Whisker bridging and whisker pulling-out were efficient in absorbing crack propagating energy, resulting in the improvement of the mechanical properties. Moreover, bioactivity and biocompatibility of the scaffolds were evaluated in vitro. The results showed that composite scaffolds with 10 wt.% HANw exhibited good apatite-forming ability and cellular affinity

An Convenient Approach to 2,4-Disubstituted Quinazoline 3-Oxides Using active MnO2 as Oxidant

Using cheap, readily available and economic active MnO2 as an oxidant, a series of 2,4-disubstituted quinazoline-3-oxides were synthesized in good to excellent yields by oxidation of the corresponding 1,2-dihydroquinazoline-3-oxides under mild conditions. The novel approach is simple and convenient, which provide a series of 2,4-Disubstituted quinazoline-3-oxides.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Silver Triflate and Palladium Acetate Co-catalyzed Reaction of <i>N</i>′-(2-Alkynylbenzylidene)hydrazide with <i>N</i>-Allyl Ynamide

A silver triflate and palladium acetate co-catalyzed reaction of <i>N</i>′-(2-alkynylbenzylidene)hydrazide with <i>N</i>-allyl ynamide is described, which generates 2-amino-<i>H</i>-pyrazolo[5,1-<i>a</i>]isoquinolines in good to excellent yield. The transformation proceeds with high efficiency through 6-<i>endo</i> cyclization, [3 + 2] cycloaddition, 3,3-sigmatropic rearrangement, and aromatization