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Tourism has had some negative effects while generating positive results. The carbon emissions produced by tourism, which is not a "smokeless industry" in traditional cognition, account for a certain proportion of the global greenhouse gas emissions. Tourism transportation, tourist accommodation, and other tourism activities all contribute to the carbon emission of tourism, and various tourism activities not only stimulate the economy but also increase air pollution. As a big industry, tourism's growth and development have continuously increased energy consumption, and the pressure on energy conservation and emission reduction has also been greatly aggravated. In this study, the tourism carbon emissions in each province of China were estimated using a "top-down" calculation model, the tourism energy consumption factors were decomposed using a logarithmic mean Divisia index model, and the driving factors of tourism carbon emissions were analyzed through a panel data model. Results show that the tourism carbon emissions in China rapidly increased from 360.74 million tons in 2006 to 853.28 million tons in 2021. The driving factors of tourism energy consumption in China are economic development, energy efficiency, and population, while the inhibiting factors are tourism intensity and energy structure. The per capita GDP, the proportion of the tertiary industry, the turnover of tourists, and the level of urbanization all significantly promote the growth of tourism carbon emissions in China at 1%. The research results are of great significance to the proposal of measures for tourism carbon emission reduction in combination with the situation of various provinces and cities, promoting regional economic development and boosting the development of tourism in China under the background of a low-carbon economy. [ABSTRACT FROM AUTHOR]

The influence of quenching temperature and holding time in dual-phase region on microstructure and mechanical properties of 7Ni steel was studied by X-ray diffractometer, scanning electron microscopy and thermal dilatometer. Based on the thermal expansion curve, the production and transformation rate of reversed austenite of 7Ni steel under each stage of the QLT treatment was quantitatively measured, and the transformation process of reversed austenite was revealed. The results indicate that the transformation of reversed austenite during QLT treatment successively goes through four stages:quenching temperature holding, quenching cooling, tempering temperature holding and tempering cooling. Appropriately improving the quenching temperature in dual-phase region and extending the holding time is beneficial to the transformation of reversed austenite during tempering, and also promotes its uniform distribution, which consequently reduces the strength and enhances the ductility as well as toughness of 7Ni steel. Under the quenching in dual-phase region treatment at 660℃ for 30min, the comprehensive mechanical properties of the 7Ni steel are the best, which completely meet the mechanical property requirements of 9Ni steel stipulated by ASTM A553.

A method for the synthesis of propargylic formates from propargylic alcohols and sodium chlorodifluoroacetate is reported. In the reaction, sodium chlorodifluoroacetate is used as a difluorocarbene precursor and a formylating reagent to provide a carbonyl source, while the triple bond of propargylic alcohols is not involved. The method shows convenient operation, good functional group tolerance and high site‐selectivity under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Synaptic transistors are important component of neuromorphic computing systems, which is promising to reduce data traffic, time delay, and energy cost. However, most of synaptic behaviors normally need the aid of electrostatic gate voltage, which induces considerable consumption. Here, we propose a structure of the electrostatic aid-free photo-floating gate transistor based on the MoS2/MoOx/WSe2 heterojunctions, in which the MoOx acts as a unipolarity barrier layer and WSe2 functions as a photo-floating gate layer. Compared with the traditional floating-gate transistors, the designed device exhibits the distinct characteristics of visual synapse behaviors without the electrostatic aid gate, including the multilevel storage property of 13 stages, paired-pulse facilitation, the transition of short time plasticity to long time plasticity, and learning-forgetting-learning. This work provides a feasible strategy to construct neuromorphic computing device with ultra-low energy consumption. [ABSTRACT FROM AUTHOR]

This aim of this work was to develop a low-cost, high-performance cement-based composite using straw cotton straw fibre (CSF) and expanded polystyrene (EPS). To this end, cement mortar specimens with different proportions of CSF (5%, 10% and 15%) and EPS (1%, 2% and 3%) were prepared. A control group (CG), without CSF or EPS was also tested. The compressive strengths, anti-splitting and flexural strengths of the specimens with different mix proportions were tested at for 7 days and 28 days. The thermal conductivity and water absorption of the specimens at 28 days were also measured. It was found that, for a constant content of CSF or EPS, the compressive strength and axial compressive strength of the samples at 28 days decreased with an increase of EPS or CSF content. The maximum compressive and axial compressive strengths of the CSF–EPS specimens were 37% and 42.6% lower than those of the CG, respectively, whereas the maximum flexural and anti-splitting strengths were 33% and 94% more than those of the CG. With an increase in the content of CSF and EPS, the water absorption of the specimens increased, whereas the thermal conductivity decreased. The cementitious composite made with 5–10% CSF and 1–2% EPS met the requirements for the mechanical properties and thermal insulation performance of self-insulating blocks. [ABSTRACT FROM AUTHOR]

To investigate the factors associated with the duration of severe acute respiratory syndrome coronavirus 2 RNA shedding in patients with coronavirus disease 2019 (COVID‐19). A retrospective cohort of COVID‐19 patients admitted to a designated hospital in Beijing was analyzed to study the factors affecting the duration of viral shedding. The median duration of viral shedding was 11 days (IQR, 8‐14.3 days) as measured from illness onset. Univariate regression analysis showed that disease severity, corticosteroid therapy, fever (temperature>38.5°C), and time from onset to hospitalization were associated with prolonged duration of viral shedding (P <.05). Multivariate regression analysis showed that fever (temperature>38.5°C) (OR, 5.1, 95%CI: 1.5‐18.1), corticosteroid therapy (OR, 6.3, 95%CI: 1.5‐27.8), and time from onset to hospitalization (OR, 1.8, 95%CI: 1.19‐2.7) were associated with increased odds of prolonged duration of viral shedding. Corticosteroid treatment, fever (temperature>38.5°C), and longer time from onset to hospitalization were associated with prolonged viral shedding in COVID‐19 patients. Highlights: Corticosteroid treatment was associated with prolonged viral shedding in COVID‐19 patients [ABSTRACT FROM AUTHOR]

The reaction mechanisms for acetylene cyclotrimerization using TiO2 and Ti catalysts were studied by the density functional theory (DFT) method. Interestingly, the reaction catalysed by TiO2 occurs on the potential energy surface (PES) with a singlet state. For the same reaction catalysed by Ti, spin‐orbit coupling (SOC) calculations were performed to discuss spin inversion between the triplet and singlet PESs. The chance that an electron hops in the vicinity of the minimum‐energy crossing point (MECP) was verified regarding the Landau‐Zener model. The possibilities of single (P1ISC) and double (P2ISC) at MECP1 (SOC = 253.38 cm−1) are about 0.35 and 0.46, respectively. The energetic span model developed by Kozuch was applied in the above reactions. The turnover frequency (TOF)‐determining transition state (TDTS) and TOF‐determining intermediate (TDI) were verified. The TOF value indicates that Ti is a more active catalyst compared with TiO2 in C2H2 cyclotrimerization. The reaction mechanisms for acetylene cyclotrimerization using TiO2 and Ti catalysts were studied by density functional theory method. The turnover frequency (TOF) value indicates that Ti is a more active catalyst compared with TiO2 on the C2H2 cyclotrimerization. [ABSTRACT FROM AUTHOR]

Introduction: The nursing management of intracranial hypertension in adult patients with severe brain injury is crucial for maintaining the stability of intracranial pressure, which ultimately improves patient outcomes., Objectives: This project aimed to implement evidence-based practices for the nursing management of intracranial hypertension in adult patients with severe brain injury., Methods: This evidence implementation project was conducted in a neurosurgery intensive care unit in a large tertiary hospital in Guangzhou, China. The project was guided by the JBI Evidence Implementation Framework, which is an audit and feedback model with seven stages. The Ottawa Model of Research Use was used to identify barriers and facilitators to best practices and to develop improvement strategies., Results: Thirty-three nurses and 50 patients with severe brain injury participated in the baseline and follow-up audits. After project implementation, follow-up audits revealed significantly improved compliance with best practices compared with baseline. Nurses' awareness of best practices increased (41% to 96%); nursing assessment, monitoring, and interventions related to intracranial hypertension rose significantly (from 82%, 75%, and 59% to 98%, 84%, and 87%, respectively); and patients' optic nerve sheath diameter was notably lower (6.002±0.677 mm to 5.698±0.730 mm)., Conclusions: The systematic integration of consistent training and education, together with the refinement of care processes and the creation of relevant tools, led to a significant improvement in awareness and adherence to best practices. Further testing of this program in more hospitals is needed., Spanish Abstract: http://links.lww.com/IJEBH/A243., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 JBI. Unauthorized reproduction of this article is prohibited.)