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"Global Engineering Education Accreditation" (GEEA) is an internationally accepted quality assurance system for engineering education in universities, and technology competitions for college students are also considered important approaches to achieve the educational objectives and meet graduation requirements of GEEA in practice aspects. In this paper, the competency of guiding teachers of technology competitions for Chinese college students is evaluated through a case of "National Competition of Transportation Science and Technology for Students" (NACTranS). Firstly, 7 theoretical hypotheses of the modified "structural equation modeling" (SEM) for competency were developed by concentrating on some principles pertaining to the key concepts of GEEA. Secondly, competition results were set as the dependent variable and 3 dimensions of competition (topic selecting, works producing and team managing) were set as the independent variables under the modified SEM. Meanwhile, both administrative ranks and regional locations of universities where guiding teachers work were set as intervening vectors so as to explain the formation mechanisms of competency. Thirdly, a case study of NACTranS data from 68 universities in China's mainland was done through modified SEM calculating. The conclusions indicate that competency of guiding teachers is not only represented by 3 dimensions but also indirectly manipulated by 2 intervening vectors. According to the case calculating by modified SEM, the determinant of guiding teachers' performance in topic selecting is the administrative ranks of universities, whereas their performance in works producing is dictated by the regional locations of universities. Various improvements on the competency of guiding teachers can be carried out in schools of engineering in Chinese universities, such as sufficient academic communications, efficient industry-university-research cooperation and so on.

The deprotonation of acetohydroxamic acid(AHA) and its coordination chemistry with uranyl ion(\begin{document}${\mathrm{UO}}_2^{2+ }$\end{document}) in 1.0 mol/L NaClO4 has been investigated with potentiometric titration and Raman spectroscopy at 25 ℃. For the first time, the deprotonations of AHA in aqueous solutions are quantitatively investigated with potentiometric titration method. It is found that in aqueous solution AHA acts as a monobasic acid and the protonation constants calculated to be pKa1=9.24±0.11(errors are given by the HyperQuad software fitting calculations). The determined pKa1 is in good agreement with the previously reported one-step protonation. In a wide pH range from acidic to basic aqueous solutions, the two step-wise protonation of AHA has been found, at the same time, the complexation of U(Ⅵ) with AHA has been re-visited. For AHA at different degrees of deprotonation, various complexes of U(Ⅵ) with AHA at ratios of U(Ⅵ) and AHA from 1∶1 to 1∶3 are recognized by potentiometric titration method. Amongst, the 1∶1 set of complexes consists of UO2A+ and UO2(OH)A, the 1∶2 includes UO2A2 and UO2(OH)\begin{document}${\mathrm{A}}_2^{-} $\end{document}, and the 1∶3 is composed of three complexes UO2\begin{document}${\mathrm{A}}_3^{-} $\end{document}, UO2(OH)\begin{document}${\mathrm{A}}_3^{2-} $\end{document} and UO2(OH)2\begin{document}${\mathrm{A}}_3^{3-} $\end{document}. There are maybe more complex species formed during the titrations, especially in very basic solutions, but those cannot be well quantitatively characterized due to their very low solubilities. The stability constants of the mentioned seven species have been determined by HyperQuad software, with the values of UO2A+ and UO2A2 in good consistence with those reported previously. All other five new-detected complexes are detected in solutions of relatively higher pH values. In the potentiometric titrations at relatively low AHA concentration, both protons of AHA can be deprotonated to form higher proportioned UO2(OH)A in comparison with UO2A2, which is an equal species to UO2A+ in term of releasing/consuming H+ during the titration process. At greatly excessive concentrations of AHA, three complexes, UO2A+, UO2A2, and UO2\begin{document}${\mathrm{A}}_3^{-} $\end{document} are successively formed with only one proton deprotonated A− as the pH being increased; further, two species, UO2(OH)\begin{document}${\mathrm{A}}_3^{2-} $\end{document} and UO2(OH)2\begin{document}${\mathrm{A}}_3^{3-} $\end{document}, are formed with partial of the ligands in the form of completely deprotonated (OH)A2−. The Raman spectroscopic titrations show that the Raman shift of O=U=O moves to lower wavenumbers with the increase in the number of ligands, with 849 cm−1, 828 cm−1 and 807 cm−1 corresponding to the three sets of U(Ⅵ) to AHA ratios of 1∶1, 1∶2, and 1∶3, respectively. Moreover, the results demonstrate that the effect of deprotonation on the Raman shifts of uranyl ion is negligible, but the effect on the Raman intensity is significant. The almost same step-wise Raman shifts at about 21 cm−1 for the three sets of complexes, 1∶1, 1∶2 and 1∶3, indicates a similar coordination mode for all the AHA ligands with different degrees of deprotonation, which provides informative hints for the structures of the complexes.

Critically ill patients are at high risk for hospital acquired infections, which can significantly increase the mortality rate and treatment costs for these patients. Therefore, in the process of treating the primary disease, strict prevention and control of new hospital infections is an essential component of the treatment for critically ill patients. The treatment of critically ill patients involves multiple steps and requires a concerted effort from various aspects such as theory, management, education, standards, and supervision to achieve effective prevention and control of hospital infections. However, there is currently a lack of unified understanding and standards for hospital infection prevention and control. To address this, in March 2024, a group of experts in critical care medicine, infectious diseases, and hospital infection from China discussed the current situation and issues of hospital infection control in the intensive care unit together. Based on a review of the latest evidence-based medical evidence from both domestic and international sources, 2024 Expert Consensus on Hospital Acquired Infection Control Principles in the Department of Critical Care Medicine was formed, aiming to provide a basis for the development of hospital infection prevention and control strategies in the field of critical care medicine.

Hospital acquired infections in critically ill patients are characterized by high incidence and poor prognosis, but the specific population may benefit from pharmacologic prophylaxis. For patients with ventilator-associated pneumonia, prophylaxis with systemic application or nebulized inhalation of antibiotics may be considered as a choice, depending on the characteristics of the patients and the time onset of the disease. For invasive aspergillosis (IA) in the department of critical care medicine, new perception is needed for its diagnosis and the need for prophylactic antifungal therapy should be evaluated for the high-risk group of IA. Reactivation of CMV is not uncommon in the department of critical care medicine, and prophylactic antiviral treatment may reduce the incidence of reactivation, but whether it improves clinical outcomes requires further exploration. When considering pharmacologic prophylaxis, it is necessary to conduct a thorough risk-benefit assessment of the target population, the type of drugs, and the mode of administration.

The transition from mafic to felsic upper continental crust (UCC) is crucial to habitability of Earth, and may be related to the onset of plate tectonics. Thus, defining when this crustal transition occurred has great significance for the evolution of Earth and its inhabitants. We demonstrate that V isotope ratios (reported as δ51V) provide insights into this transition because they correlate positively with SiO2 and negatively with MgO contents during igneous differentiation in both subduction zones and intraplate settings. Because δ51V is not affected by chemical weathering and fluid-rock interactions, δ51V of the fine-grained matrix of Archean to Paleozoic (3 to 0.3 Ga) glacial diamictite composites, which sample the UCC at the time of glaciation, reflect the chemical composition of the UCC through time. The δ51V values of glacial diamictites systematically increase with time, indicating a dominantly mafic UCC at ~3 Ga; the UCC was dominated by felsic rocks only after 3 Ga, coinciding with widespread continental emergence and many independent estimates for the onset of plate tectonics.

BackgroundChronic respiratory disease is an important public health problem in the United States and globally. Diet, an important part of a healthy lifestyle, is also relevant to chronic respiratory health. We aimed to explore the relationship between overall dietary quality and the risk of chronic respiratory disease (CRD), include chronic bronchitis (CB), emphysema and asthma.MethodA total of 4,499 United States adults were extracted from the National Health and Nutrition Examination Survey (NHANES) in 2017–2018. Diet quality was assessed using 2 day, 24 h dietary recall data and quantified as the Healthy Diet Index (HEI)-2020 score. Binary logistic regression models, restricted cubic splines (RCS) and generalized additive modeling (GAM), the weighted quartile sum (WQS) and qgcom models were used to assess the relationship between HEI-2020 scores and risk of CB, emphysema and asthma.ResultsHigh HEI-2020 scores are associated with low risk of chronic respiratory disease (CB: 0.98, 0.97–0.99; emphysema: 0.98, 0.97–0.99; asthma: 0.98, 0.97–0.99) and consistent results across different dietary variable categorization (Tertile: CB: 0.58, 0.42–0.81; asthma: 0.51, 0.35–0.74; Quartile: CB: 0.57, 0.34–0.97; asthma: 0.56, 0.36–0.86) and different weighting models. Negative dose-response relationship between dietary quality and risk of chronic respiratory disease also shown in RCS and GAM models. The WQS and qgcom models also showed a healthy mixing effect of dietary components on respiratory disease, with high-quality proteins, vegetables, and fruits making the heaviest contributions.ConclusionHigher HEI-2020 scores were associated with lower risk of CB, emphysema, and asthma. Following Dietary Guidelines for Americans 2020–2025 could support enhanced respiratory health.