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Fine-scale population estimation (FPE) is crucial for urban management. After training, the bottom-up FPE models can be applied independently of census data. However, given the lack of real fine-scale population data, the existing bottom-up methods typically apply models trained on coarse-grained census data to FPE directly, causing estimation bias induced by scale effects. Traffic analysis zones (TAZs) balance geo-semantics and fine granularity, but their potential as population analysis units has not been fully exploited. Hence, we developed a weakly-supervised TAZ-scale bottom-up population estimation method (WSTP). Specifically, to mitigate scale effects, the weakly-supervised training procedure involves fine-scale feature input, model prediction, spatial aggregation, and coarse-scale supervision is designed to ensure that WSTP consistently focuses on FPE throughout the training and prediction phases. To enable weakly-supervised training using census data, we treated TAZs as graph nodes and designed a Spatial Aggregation Layer to aggregate TAZ-scale population predictions into communities. Given the diverse distribution patterns across age groups, we decomposed the FPE task by age groups. The experiments showed that WSTP significantly outperformed the baselines with R² values of 0.821 and 0.785 at the community and TAZ scales, respectively, indicating that WSTP can mitigate scale effects and produce high-resolution, accurate population data. [ABSTRACT FROM AUTHOR]

• Continuous modal-parameter tracking is proposed to detect frequency veering phenomena. • A frequency locus may veer more than once due to different types of modal coupling between the car body vertical bending and the under-chassis equipment vertical vibrations. • The proportions of the car body bending vector magnitudes associated with the natural frequency of the equipment on each veering mode before veering are interchanged during the veering. • The effects of the frequency veering phenomena should be considered for hanging frequency of under-chassis equipment. The coupled system of the car body and the under-chassis equipment is a significant part of the railway vehicle and directly influences the vehicle dynamics. A continuous modal parameter tracking method is proposed to analyse the frequency veering phenomenon occurring between a car body and under-chassis equipment. Veering determination methods based on the modal assurance criterion, mode shape similarity and phase difference were proposed. Results show that altering the natural frequency of the under-chassis equipment causes frequency veering between the first-order vertical bending of the car body and vertical motion of the under-chassis equipment. For the car body with a single under-chassis equipment, frequency veering occurs when the natural frequency of the under-chassis equipment approach the frequency of the first-order vertical bending mode of the car body without under-chassis equipment, and the modal damping of the veering modes changes significantly in the veering zone and intersect at the veering point. The proportions of the car body bending vector magnitudes associated with the natural frequency of the equipment on each veering mode before veering are interchanged during the veering. Furthermore, when the natural frequency of the under-chassis equipment is equal to that at the veering point, the vibration transmissibility near the car body first-order bending motion is the lowest. For the car body with multiple under-chassis equipment, a frequency locus may veer more than once due to different types of modal coupling between the car body vertical bending and the under-chassis equipment vertical vibrations. When the natural frequency of the under-chassis equipment is equal to that of the modal damping intersection point, the vibration transmissibility near the car body first-order bending motion is minimal. [ABSTRACT FROM AUTHOR]

Abstract  Monodisperse titania/polymer core-shell microspheres were prepared by a two-stage reaction with titania as core and poly(ethyleneglycol dimethacrylate) (PEGDMA) as shell, in which the titania cores were synthesized by a sol-gel method and subsequently grafted with 3-trimethoxysilyl methacrylate as the first-stage reaction to incorporate the vinyl groups on the surface of inorganic core. The PEGDMA shell was then encapsulated over the MPS-modified titania core by distillation precipitation polymerization of ethyleneglycol dimethacrylate in neat acetonitrile during the second-stage polymerization via capture of the radicals of EGDMA with the aid of the reactive vinyl groups on the surface of inorganic core without any stabilizer or surfactant. The shell thickness of the core-shell hybrid microspheres was controlled by the feed of EGDMA monomer during the polymerization. The resultant titania particles and core-shell microspheres were studied by transmission electron microscopy, Fourier-transform infrared spectra, X-ray photoelectron spectroscopy, and thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

Streptococcus pneumoniae is the most common pathogenic bacterium of pneumonia and can cause death. Here, we examined the impact of Baicalein on mouse mortality caused by Streptococcus pneumoniae infection. Baicalein protected mice from Streptococcus pneumoniae -induced deaths. Baicalein reduced alveolocapillary membrane permeability, lung infiltration of inflammatory cells, inflammatory cytokine production and pulmonary cell apoptosis. These evidences show that Baicalein is useful in the therapy of a severe form of pneumonia that can cause deaths.