Abstract A comprehensive emergency medical service (EMS) system significantly enhances a city’s capacity to prevent and mitigate disasters. Using Huangshi as a case study, this research evaluated the ...service radium coverage rate of the current EMS system by examining its transport capacity, population density, and prevalence rate, finding it to be only 61.49% with an inefficient spatial layout. To address this, we proposed transforming urban brownfields into EMS parks. By selecting the most suitable brownfields based on capacity and service radius, we increased the coverage rate to 90.21%. We introduced a new "consultation-referral" model, where existing EMS facilities serve as pre-diagnosis and triage centers, and the urban brownfield EMS parks function as isolation and centralized treatment centers. GIS network analysis confirmed the feasibility, showing all transit times to be under 30 min. The methodology outlined in this study—comprising "demand assessment, supply optimization, and feasibility verification"—not only strengthens the city’s EMS system but also facilitates the renewal of urban brownfields. This approach can serve as a valuable reference for enhancing EMS systems in other cities.
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•Using PTASA to promote PTL pyrolysis for high-quality syngas was firstly proposed.•The kinetic mechanism of PTASA in the pyrolysis of PTL was revealed.•PTASA mainly decreased the ...activation energy of Lignin in PTL by19%.•High-quality syngas increased evidently from 0.415 to 0.523 L/g with PTASA.•Inherent minerals in PTASA could break macromolecule bonds to promote PTL pyrolysis.
To improve pyrolysis syngas of Phoenix Tree’s Leaves (PTL), the synergistic effect of Purified Terephthalic Acid Sludge Ash (PTASA) was comprehensively investigated. In kinetics analysis, the thermal decomposition of PTL could be divided into three pseudoreactions while PTL + PTASA was with four pseudoreactions owing to the decomposition of CaCO3 as well as the reduction of inherent metal compounds (Co(II), Mn(III, IV), etc). Meanwhile, the reaction models for pseudoreaction 1 (P1) ∼ pseudoreaction 4 (P4) were fitted as D3, R2 and D3, and A15, respectively. The Ea (average activation energy) of PTL + PTASA during pyrolysis (200 ∼ 600 °C) was 6.2 % lower than the monopyrolysis which was mainly caused by the decrease of Ea in the decomposition of lignin. In addition, the crystal structure e.g. CaMnO3 (ABO3), Ca3Co2O6 (A3BB’O6), and CoO in PTASA could effectively promote the production of high-quality syngas from 41.34 % to 61.76 %. Moreover, the reaction pathways in pyrolysis of PTL + PTASA showed that the PTASA could promote the CC bond, CO bond, and C–H bond breaking of the macromolecules, e.g. anhydrosugars, N-containing compounds, and aldehydes, to produce the small molecules and release syngas. This study could provide a useful strategy for clean, valuable, and sustainable resource utilization of waste resources.
This paper presents a preliminary experimental investigation on magnetohydrodynamic （MHD） power generation using seeded supersonic argon flow as working fluid. Helium and argon are used as driver and ...driven gas respectively in a shock tunnel. Equilibrium contact surface operating mode is used to obtain high temperature gas, and the conductivity is obtained by adding seed K2CO3 powder into the driven section. Under the conditions of nozzle inlet total pressure being 0.32 MPa, total temperature 6 504 K, magnetic field density about 0.5 T and nozzle outlet velocity 1 959 m/s, induction voltage and short-circuit current of the segmentation MHD power generation channel are measured, and the experimental results agree with theoretical calculations; the average conductivity is about 20 S/m calculated from characteristics of voltage and current. When load factor is 0.5, the maximum power density of the MHD power generation channel reaches 4.797 1 MW/m3, and the maximum enthalpy extraction rate is 0.34%. Finally, the principle and method of indirect testing for gas state parameters are derived and analyzed.
Dear Editor,
Cellular senescence is a state of irreversible proliferative arrest that is believed to be an important determinant of both cancer development and organismal aging 1. Although numerous ...molecules have been found to promote senescence, little is known about the nature of anti-senescent factors under physiological conditions.
The 501Y.V2 variants of SARS-CoV-2 containing multiple mutations in spike are now dominant in South Africa and are rapidly spreading to other countries. Here, experiments with 18 pseudotyped viruses ...showed that the 501Y.V2 variants do not confer increased infectivity in multiple cell types except for murine ACE2-overexpressing cells, where a substantial increase in infectivity was observed. Notably, the susceptibility of the 501Y.V2 variants to 12 of 17 neutralizing monoclonal antibodies was substantially diminished, and the neutralization ability of the sera from convalescent patients and immunized mice was also reduced for these variants. The neutralization resistance was mainly caused by E484K and N501Y mutations in the receptor-binding domain of spike. The enhanced infectivity in murine ACE2-overexpressing cells suggests the possibility of spillover of the 501Y.V2 variants to mice. Moreover, the neutralization resistance we detected for the 501Y.V2 variants suggests the potential for compromised efficacy of monoclonal antibodies and vaccines.
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•501Y.V2 showed no higher infectivity in cells with hACE2 comparing to 614G variant•501Y.V2 showed increased infectivity in cells with mACE2 compared to 614G variant•501Y.V2 escaped neutralization by most of neutralizing monoclonal antibodies•501Y.V2 significantly compromised the inhibitory effects of polyclonal antibodies
Experiments with pseudotyped viruses show that the 501Y.V2 variant of SARS-CoV-2 exhibits resistance to neutralization from monoclonal antibodies and sera from convalescent as well as immunized individuals, predominantly due to the E484K and N501Y mutations in the receptor-binding domain of the viral spike protein.
The fundamental goal of artificial intelligence (AI) is to mimic the core cognitive activities of human. Despite tremendous success in the AI research, most of existing methods have only ...single-cognitive ability. To overcome this limitation and take a solid step towards artificial general intelligence (AGI), we develop a foundation model pre-trained with huge multimodal data, which can be quickly adapted for various downstream cognitive tasks. To achieve this goal, we propose to pre-train our foundation model by self-supervised learning with weak semantic correlation data crawled from the Internet and show that promising results can be obtained on a wide range of downstream tasks. Particularly, with the developed model-interpretability tools, we demonstrate that strong imagination ability is now possessed by our foundation model. We believe that our work makes a transformative stride towards AGI, from our common practice of "weak or narrow AI" to that of "strong or generalized AI".
The goal of investors in the hotel business is to maximize profits, and the price is an important means of achieving this goal. This has attracted many scholars to study the spatiotemporal ...relationship between hotel room prices and their possible influencing factors from different perspectives. However, most existing studies adopt the linear assumption of the hedonic model, with limited features and a lack of feature selection procedures. Additionally, there are few forecasts of hotel pricing from a spatial perspective. To overcome these gaps, this study adopts linear and nonlinear machine learning methods based on the “big data” of Sanya City to explore the influencing factors of budget hotel pricing. Based on the spatial perspective, 81 potential factors were considered. They are further selected using a feature extraction model called recursive feature elimination. Six machine-learning algorithms were evaluated and compared: random forest, extreme gradient boosting, multi-linear regression, support vector regression, multilayer perceptron regression, and K-nearest neighbor regression. The optimal value was used to further calculate the feature importance. They disclosed 40 important impact characteristics and predicted the spatial distribution of hotel pricing.
As sequencing depth of chromatin studies continually grows deeper for sensitive profiling of regulatory elements or chromatin spatial structures, aligning and preprocessing of these sequencing data ...have become the bottleneck for analysis. Here we present Chromap, an ultrafast method for aligning and preprocessing high throughput chromatin profiles. Chromap is comparable to BWA-MEM and Bowtie2 in alignment accuracy and is over 10 times faster than traditional workflows on bulk ChIP-seq/Hi-C profiles and than 10x Genomics' CellRanger v2.0.0 pipeline on single-cell ATAC-seq profiles.
By systematically summarizing horizontal well fracturing technology abroad for shale oil and gas reservoirs since the “13th Five-Year Plan”, this article elaborates new horizontal well fracturing ...features in 3D development of stacked shale reservoirs, small well spacing and dense well pattern, horizontal well re-fracturing, fracturing parameters optimization and cost control. In light of requirements on horizontal well fracturing technology in China, we have summarized the technological progress in simulation of multi-fracture propagation, horizontal well frac-design, electric-drive fracturing equipment, soluble tools and low-cost downhole materials and factory-like operation. On this basis, combined with the demand analysis of horizontal well fracturing technology in the “14th Five-Year Plan” for unconventional shale oil and gas, we suggest strengthening the research and development in the following 7 aspects: (1) geology-engineering integration; (2) basic theory and design optimization of fracturing for shale oil and gas reservoirs; (3) development of high-power electric-drive fracturing equipment; (4) fracturing tool and supporting equipment for long horizontal section; (5) horizontal well flexible-sidetracking drilling technology for tapping remaining oil; (6) post-frac workover technology for long horizontal well; (7) intelligent fracturing technology.
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