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The air quality in classrooms significantly impacts school children's health and learning performance. It has been reported worldwide that classroom air quality does not meet the required standard and actions are pledged for improvement. However, it poses a challenge for decision-making in terms of prioritising taking-up measures. The aim of this study is to propose a method of identifying the action measures for improving classroom air quality and prioritising them. Case studies in the UK and China were conducted, and the key measures were identified through literature studies, open-ended questionnaire surveys, and workshop discussions, which are classified into three categories: B1, policy; B2, technology; and B3, information sharing. The analytical hierarchy process (AHP) is applied in the prioritisation of the action measures. A total of 138 teachers and parents from China and the UK participated in this case study. The genetic algorithm-optimised Hadamard product (GAOHP) method is applied to justify the consistency ratio (CR) within the required threshold value in order to ensure the consistency of the subjective perception and the accuracy of comparative weights. The results show that item B2, technology, is the most desired measure by both Chinese and British parents and teachers, despite the deviation from the optimal choice in China and the UK. Among the proposed action measures, the UK respondents strongly expected air purifiers with natural ventilation as opposed to their Chinese counterparts preferring to share the real-time status of classroom air quality. Our work will provide strong support for the subsequent selection of indoor air quality improvement strategies for schools. [ABSTRACT FROM AUTHOR]

A miniaturized planar microstrip circularly polarized ultrawideband (UWB) antenna loaded by annular-ring slot is proposed and implemented in the paper. With the annular-ring slot loaded in the radiating patch of the antenna, the side of the radiating patch is connected by the asymmetric inverted L-shaped microstrip. At the same time, a quarter of a circle is cut off from the radiating patch. The above designed structure shows improvements on the operating frequency band and realization of the circular polarization radiation. A tapered microstrip is placed between the feed line and the radiating patch to achieve the slow-changing impedance transformation. The results of simulation and measurement demonstrate that the 3 dB axial ratio (AR) fractional bandwidth of the antenna structure achieves 21.25%. The peak gain within the 3 dB axial ratio bandwidth fluctuates between 3.74 and 4.59 dBi. The antenna shows good impedance matching in the ultrawideband range. With the compact structure of the UWB antenna, it has potential application in various wireless communication devices.

Through the use of the measure theory, evolution family, “Acquistapace–Terreni” condition, and Hölder inequality, the core objective of this work is to seek to analyze whether there is unique μ-pseudo almost periodic solution to a functional evolution equation with Stepanov forcing terms in a Banach space. Certain adequate conditions are derived guaranteeing there is unique μ-pseudo almost periodic solution to the equation by Lipschitz condition and contraction mapping principle. Finally, an example is used to demonstrate our theoretical findings.

The mechanical performance and failure mechanism of a retard-bonded (RB) type prestressed concrete (PC) girder in different curing periods are investigated through four-point loading experiments. Six RB-type PC girder specimens with three RB prestressed tendons (PTs) along the longitudinal direction were fabricated. The measurements include the following: the retard-bonded agent ages versus the load-carrying capacity of the girder, the deflection of girder, the strain distribution at key cross sections through the girder, the pressure at PT tensile and anchoring ends, crack distribution, and so on. The experimental results indicate that when stretching the PT within proper tensile period, the retarder curing ages have less impact on the cracking load and a greater impact on the ultimate bending strength; the ultimate bending strength of the RB-type PC girder increased with increased retarder curing. Nonetheless, stretching the PT after excessive retarder curing (after the retarder had solidified completely), the cracks in the PC girder’s pure bending segment are wider and less numerous, the ultimate bending strength of the girder is lower, and its ductility is poor.

This paper proposes a new fractional-order approach for synchronization of a class of fractional-order chaotic systems in the presence of model uncertainties and external disturbances. A simple but practical method to synchronize many familiar fractional-order chaotic systems has been put forward. A new theorem is proposed for a class of cascade fractional-order systems and it is applied in chaos synchronization. Combined with the fact that the states of the fractional chaotic systems are bounded, many coupled items can be taken as zero items. Then, the whole system can be simplified greatly and a simpler controller can be derived. Finally, the validity of the presented scheme is illustrated by numerical simulations of the fractional-order unified system.

We explored mechanisms of vascular endothelial injury that lead to systemic multiple organ failure by detecting the soluble endothelial protein C receptor (sEPCR), von Willebrand factor (vWF), serum nitric oxide (NO), and tumor necrosis factor alpha (TNF-α) and Bcl-2 mRNA and Bax mRNA expression in a severe acute pancreatitis (SAP) rat model. Compared to controls, the levels of TNF-α, vWF, and sEPCR were significantly increased in the experimental group at 12 hours and 24 hours and the NO level was significantly decreased. After 12 hours, the aortic endothelial apoptosis index and Bax mRNA expression in aortic endothelial cells had increased in the experimental group, but Bcl-2 mRNA levels had decreased. All these changes appeared at both 12 h and 24 hours. The results indicated that vascular endothelial injury and apoptosis markers were elevated in SAP. Endothelial injury and increased apoptosis in the experimental group were related to the increased expression of TNF-α.

We prove that αH(a,b)+(1−α)L(a,b)>M(1−4α)/3(a,b) for α∈(0,1) and all a,b>0 with a≠b if and only if α∈[1/4,1) and αH(a,b)+(1−α)L(a,b)

We selected different concentrations of ethephon, to stress C. roseus. We used qRT-PCR and HPLC followed by PCA to obtain comprehensive profiling of the vinblastine biosynthesis in response to ethephon. Based on our findings, the results showed that the high concentration of ethephon had a positive effect at both transcriptional and metabolite level. Meanwhile, there was a remarkable decrease of hydrogen peroxide content and a promoted peroxidase activity in leaves. The loading plot combination with correlation analysis suggested that CrPrx1 could be regarded as a positive regulator and interacts with ethylene response factor (ERF) to play a key role in vinblastine content and peroxidase (POD) activity. This study provides the foundation for a better understanding of the regulation and accumulation of vinblastine in response to ethephon. [ABSTRACT FROM AUTHOR]

Let (M,g) be a surface and let (U(TM),G) be the unit tangent bundle of M endowed with the Sasaki metric. We know that any curve Γ(s) in U(TM) consist of a curve γ(s) in M and as unit vector field X(s) along γ(s). In this paper we study the geometric properties γ(s) and X(s) satisfying when Γ(s) is a slant geodesic. [ABSTRACT FROM AUTHOR]

The improved bacterial foraging algorithm was applied in this paper to schedule the bus departing interval. Optimal interval can decrease the total operation cost and passengers' mean waiting time. The principles of colony sensing, chemotactic action, and improved foraging strategy made this algorithm adaptive. Based on adaptive bacteria foraging algorithm (ABEA), a model on one bus line in Hohhot city in China was established and simulated. Two other algorithms, original bacteria foraging algorithm (BFA) and genetic algorithm (GA), were also used in this model to decide which one could greatly accelerate convergence speed, improve searching precision, and strengthen robustness. The final result showed that ABFA was most feasible in optimizing variables. [ABSTRACT FROM AUTHOR]

Summary: Introduction: Blood donation has been proposed as a potential therapy to reduce risk of cardiovascular disease, but the effects of phlebotomy on vascular function in human subjects have not been well characterized. Aims: We conducted a prospective randomized double‐blind study to determine the effects of serial phlebotomy on vascular endothelial function in the brachial artery. Eighty‐four iron‐replete, non‐anemic subjects were randomly assigned to one of three study treatment groups: (a) four serial phlebotomy procedures each followed by intravenous infusion of placebo normal saline; (b) four serial phlebotomy procedures each followed by intravenous infusion to replete lost iron; and (c) four serial sham phlebotomy procedures each followed by intravenous infusion of placebo normal saline. Assigned phlebotomy procedures were conducted at 56‐day intervals. We measured brachial artery reactivity (BAR, %) in response to transient oxidative stress induced by oral methionine with high‐resolution duplex ultrasound imaging before and one week after the fourth study phlebotomy. Results: Before phlebotomy, oral methionine decreased BAR by −2.04% (95% CI −2.58%, −1.50%), P < 0.001) with no significant difference between groups (P = 0.42). After phlebotomy, the BAR response to oral methionine did not significantly change between groups (P = 0.53). Brachial artery nitroglycerin‐mediated dilation did not change in response to phlebotomy. Conclusions: Four serial phlebotomy procedures over six months with or without intravenous iron supplementation did not alter vascular endothelial function in the brachial artery when compared with sham phlebotomy. [ABSTRACT FROM AUTHOR]