99 research outputs found

    Students' evacuation behavior during an emergency at schools:A systematic literature review

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    Disasters and emergencies frequently happen, and some of them require population evacuation. Children can be severely affected during evacuations due to their lower capability to analyze, perceive, and answer disaster risks. Although several studies attempted to address the safety of children during the evacuation, the existing literature lacks a systematic review of students' evacuation behavior during school time. Therefore, this study aims to conduct a systematic literature review to explore how students' evacuation behavior during school time has been addressed by previous scholars and identify gaps in knowledge. The review process included three steps: formulating the research question, establishing strategic search strategies, and data extraction and analysis. The studies have been identified by searching academic search engines and refined the recognized publications unbiasedly. The researchers have then thematically analyzed the objectives and findings of the selected studies resulting in the identification of seven themes in the field of students' evacuation behavior during school time. Finally, the study put forward suggestions for future research directions to efficiently address the recognized knowledge gaps.</p

    A 2,2′-bipyridine-palladacycle catalyzed the coupling of arylboronic acids with nitroarenes

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    AbstractA novel palladium-catalyzed protocol for the synthesis of diaryl ethers derivatives has been developed. In the presence of 2,2′-bipyridine-cyclopalladated ferrocenylimine complex (Cat. Ic), diaryl ethers were selectively generated by adjusting reaction parameters through the coupling of arylboronic acids and nitroarenes with yields ranging from poor to good. The efficiency of this reaction was demonstrated by its compatibility with a range of groups. Moreover, the rigorous exclusion of air or moisture was not required in these transformations

    A mechanism analysis of transverse weld cracks of marine thick steel plate

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    U postupku zavarivanja omotača za offshore platforme, često dolazi do poprečnih lomova zavara, čak i kada su tehnike zavarivanja, materijali za zavarivanje i brodski čelični limovi pomno odabirani. Sada, međutim, postoji mali broj istraživanja i analiza uzroka takvih oštećenja. U svrhu cjelovite analize uzroka poprečnih lomova zavara brodskog debelog čeličnog lima, ovo istraživanje koristi instrumente kao što su metaloskop, skenirajući elektronski mikroskop (SEM), energo disperzivni spektrometar (EDS) i auger elektronički spektrometar (AES). Zaključak je istraživača da su poprečni lomovi zavara lomovi zbog topline zavarivanja.In the welding process of jackets for offshore platform, transverse weld cracks occur frequently, even when welding techniques, welding materials and marine steel plates used are stringently selected. But now defect failure analysis and mechanism study on this issue are scarce. To fully study the causes of transverse weld cracks of marine thick steel plate, this research uses instruments including metalloscope, scanning electron microscope (SEM), Energy Dispersive Spectrometer (EDS) and Auger Electronic Spectrom (AES). Researchers conclude that transverse weld cracks are welding hot cracks

    Particle size-dependent microstructure, hardness and electrochemical corrosion behavior of atmospheric plasma sprayed nicrbsi coatings

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    Particle size is a critical consideration for many powder coating-related industries since it significantly influences the properties of the produced materials. However, the effect of particle size on the characteristics of plasma sprayed NiCrBSi coatings is not well understood. This work investigates the microstructures, hardness and electrochemical corrosion behavior of plasma sprayed NiCrBSi coatings synthesized using different-sized powders. All coatings mainly consist of Ni, N3B, CrB, Cr7C3 and Cr3C2 phases. The coatings produced by small particles (50–75 μm) exhibit lower porosity (2.0 ± 0.8%). Such coatings show a higher fraction (15.5 vol.%) of the amorphous phase and lower hardness (700 HV0.5) than the counterparts (8.7 vol.% and 760 HV0.5, respectively) produced by large particles (75–100 μm) with higher porosity (3.0 ± 1.6%). Meanwhile, the coatings produced from smaller particles possess a larger number of non-bonded boundaries, leading to the easier penetration of corrosive medium, as well as a higher corrosion current density (0.254 ± 0.062 μA/cm2) and a lower charge transfer resistance (0.37 ± 0.07 MΩ cm2). These distinctions are attributed to particle size-induced different melting degrees and stackings of in-flight particles during deposition

    Neural network-based model for evaluating inert nodules and volume doubling time in T1 lung adenocarcinoma: a nested case−control study

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    ObjectiveThe purpose of this study is to establish model for assessing inert nodules predicting nodule volume-doubling.MethodsA total of 201 patients with T1 lung adenocarcinoma were analysed retrospectively pulmonary nodule information was predicted by an AI pulmonary nodule auxiliary diagnosis system. The nodules were classified into two groups: inert nodules (volume-doubling time (VDT)&gt;600 days n=152) noninert nodules (VDT&lt;600 days n=49). Then taking the clinical imaging features obtained at the first examination as predictive variables the inert nodule judgement model &lt;sn&lt;/sn&gt;&gt;(INM) volume-doubling time estimation model (VDTM) were constructed based on a deep learning-based neural network. The performance of the INM was evaluated by the area under the curve (AUC) obtained from receiver operating characteristic (ROC) analysis the performance of the VDTM was evaluated by R2(determination coefficient).ResultsThe accuracy of the INM in the training and testing cohorts was 81.13% and 77.50%, respectively. The AUC of the INM in the training and testing cohorts was 0.7707 (95% CI 0.6779-0.8636) and 0.7700 (95% CI 0.5988-0.9412), respectively. The INM was effective in identifying inert pulmonary nodules; additionally, the R2 of the VDTM in the training cohort was 0.8008, and that in the testing cohort was 0.6268. The VDTM showed moderate performance in estimating the VDT, which can provide some reference during a patients’ first examination and consultationConclusionThe INM and the VDTM based on deep learning can help radiologists and clinicians distinguish among inert nodules and predict the nodule volume-doubling time to accurately treat patients with pulmonary nodules

    Actively implementing an evidence-based feeding guideline for critically ill patients (NEED): a multicenter, cluster-randomized, controlled trial

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    Background: Previous cluster-randomized controlled trials evaluating the impact of implementing evidence-based guidelines for nutrition therapy in critical illness do not consistently demonstrate patient benefits. A large-scale, sufficiently powered study is therefore warranted to ascertain the effects of guideline implementation on patient-centered outcomes. Methods: We conducted a multicenter, cluster-randomized, parallel-controlled trial in intensive care units (ICUs) across China. We developed an evidence-based feeding guideline. ICUs randomly allocated to the guideline group formed a local "intervention team", which actively implemented the guideline using standardized educational materials, a graphical feeding protocol, and live online education outreach meetings conducted by members of the study management committee. ICUs assigned to the control group remained unaware of the guideline content. All ICUs enrolled patients who were expected to stay in the ICU longer than seven days. The primary outcome was all-cause mortality within 28 days of enrollment. Results: Forty-eight ICUs were randomized to the guideline group and 49 to the control group. From March 2018 to July 2019, the guideline ICUs enrolled 1399 patients, and the control ICUs enrolled 1373 patients. Implementation of the guideline resulted in significantly earlier EN initiation (1.20 vs. 1.55 mean days to initiation of EN; difference − 0.40 [95% CI − 0.71 to − 0.09]; P = 0.01) and delayed PN initiation (1.29 vs. 0.80 mean days to start of PN; difference 1.06 [95% CI 0.44 to 1.67]; P = 0.001). There was no significant difference in 28-day mortality (14.2% vs. 15.2%; difference − 1.6% [95% CI − 4.3% to 1.2%]; P = 0.42) between groups. Conclusions: In this large-scale, multicenter trial, active implementation of an evidence-based feeding guideline reduced the time to commencement of EN and overall PN use but did not translate to a reduction in mortality from critical illness. Trial registration: ISRCTN, ISRCTN12233792. Registered November 20th, 2017
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