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Despite the importance of tourist mobility for urban tourism, mechanisms as to how these tourist activities shift throughout the day remain scarcely explored. This study fills this gap by providing a three‐step analysis framework. First, aggregated trajectory data were transformed into a directed weighted network. Then, a new community detection method was proposed to capture the spatial interactions, and two approaches were employed to quantify the evolution patterns of tourist mobility. Finally, the capability of the framework and its potential applications were explored and implemented through a case study in Xiamen, China. [ABSTRACT FROM AUTHOR]

Untreated or inadequately treated silver−containing wastewater may pose adverse effects on hu−man health and the ecological environment. Currently, significant progress has been made in the treatment of Ag(I) in wastewater using adsorption methods, with adsorbents playing a pivotal role in this process. This paper provides a systematic review of various adsorbents for the recovery and treatment of Ag(I) in wastewater, including MOFs, COFs, transition metal sulfides, metal oxides, biomass materials, and other polymeric materials. The adsorption mechanisms of these materials for Ag(I) are elaborated upon, along with the challenges currently faced. Furthermore, insights into optimizing adsorbents and developing novel adsorbents are proposed in this study. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum stress (ERS) and Toll-like receptor 2 (TLR2) signaling play an important role in inflammatory bowel disease (IBD); however, the link between TLR2 and ERS in IBD is unclear. This study investigated whether Thapsigargin (TG) -induced ER protein expression levels contributed to TLR2-mediated inflammatory response. The THP-1 cells were treated with TLR2 agonist (Pam3CSK4), ERS inducer Thapsigargin (TG) or inhibitor (TUDCA). The mRNA expressions of TLR1-TLR10 were detected by qPCR. The production and secretion of inflammatory factors were detected by PCR and ELISA. Immunohistochemistry was used to detect the expressions of GRP78 and TLR2 in the intestinal mucosa of patients with Crohn's disease (CD). The IBD mouse model was established by TNBS in the modeling group. ERS inhibitor (TUDCA) was used in the treatment group. The expression of TLRs was detected via polymerase chain reaction (PCR) in THP-1 cells treated by ERS agonist Thapsigargin (TG). According to the findings, TG could promote TLR2 and TLR5 expression. Subsequently, in TLR2 agonist Pam3CSK4 induced THP-1 cells, TG could lead to increased expression of the inflammatory factors such as TNF-α, IL-1β and IL-8, and ERS inhibitor (TUDCA) could block this effect. However, Pam3CSK4 did not significantly impact the GRP78 and CHOP expression. Based upon the immunohistochemical results, TLR2 and GRP78 expression were significantly increased in the intestinal mucosa of patients with Crohn's disease (CD). For in vivo experiments, TUDCA displayed the ability to inhibit intestinal mucosal inflammation and reduce GRP78 and TLR2 proteins. ERS and TLR2 is upregulated in inflammatory bowel disease, ERS may promote TLR2 pathway-mediated inflammatory response. Moreover, ERS and TLR2 signaling could be novel therapeutic targets for IBD. [ABSTRACT FROM AUTHOR]

This paper is concerned with the event-triggered $ \mathcal {L}_2-\mathcal {L}_\infty $ L 2 − L ∞ control problem for discrete-time Markov jump systems with DoS attacks and exogenous disturbance. Instead of one common event-triggering scheme, multiple triggering schemes are introduced to sample system signals and the event-triggered Markov closed-loop jump systems are further obtained under the full state feedback controller. Generally, mode information of subsystems is not completely available for the modules of trigger and controller such that asynchronous jump behaviour may occur among the modes of subsystems, triggering scheme and controller. Thus, a hidden Markov model (HMM) is developed to describe such asynchronous behaviour. Meanwhile, security issues of networks are widely studied in recent many literature. For discrete-time Markov jump systems, few works consider cyber attacks, especially periodic Denial-of-Service (DoS) attacks. Based on the HMM, the DoS attacks are taken into account and a set of sufficient conditions are further presented to guarantee the $ \mathcal {L}_2-\mathcal {L}_\infty $ L 2 − L ∞ control performance of the resulting Markov closed-loop jump systems. Subsequently, the design of controller and event-triggering parameters are provided by using matrix inequality method. Finally, an example is given to show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

In this study, coal fly ash was functionalized, using a simple one-step process (loading with Al3+ and sulfonation), to yield a solid acid catalyst (S/Al-CFA) with strong acid sites. The catalyst was then used to produce furfural from xylose in a biphasic system (H2O(NaCl)/tetrahydrofuran). The furfural yield reached 82% at 180 °C–60 min with catalyst/xylose ratio of 0.2:1.0 (w/w). With the reaction completed, all of the components could be effectively separated, and the furfural was 97.6% pure. The cycle and regeneration of the catalyst were evaluated, and the catalyst deactivation mechanism was investigated. [ABSTRACT FROM AUTHOR]

The increasing incidence of aircraft cargo compartment fires in recent years has caused heavy losses and drawn attention to understanding the combustion process, especially under low pressure. The present paper aims at exploring the conditions of flashover at different pressures. Experiments were conducted in Guanghan (96 kPa) and Kangding (60 kPa), which are located at different altitudes. Five different sizes of pool fires were tested and smoke temperature and heat flux were measured for flashover criteria analysis. Corresponding simulations were performed using a commercial software FDS to examine the pressure effect on the flashover phenomenon and to validate the simulation results. The critical conditions for the onset of flashover in a 1/4 MPS compartment were found to be (1) an average upper layer temperature of about 450 °C at 96 kPa or about 550 °C at 60 kPa, and (2) radiant heat flux at floor level of about 10 to 15 kW/m2 at 96 kPa or 20 to 25 kW/m2 at 60 kPa. By using the average upper layer temperature as a criterion in modeling, a relatively accurate prediction of flashover onset time could be obtained at 96 kPa and a delay of about 25 s was found at 60 kPa. [ABSTRACT FROM AUTHOR]

Summary: With the advancement of global positioning systems and communication technologies, location‐based services (LBS) have become widely used. However, user location privacy is vulnerable during service exchange, and location‐related queries may result in serious privacy disclosure issues. In this article, considering that attackers may make use of auxiliary information to track a mobile user, we propose a real‐time privacy‐preserving scheme based on the grouping of queries in continuous LBS. In this scheme, we first design the probability density functions to select k−1$$ k-1 $$ virtual locations. Then, we group these virtual locations and the query location of the user into several queries. Simultaneously, we send these grouping queries to the LBS server. Following the steps outlined above, grouping queries can be used to conceal the true query. Moreover, the results of security analyses and performance evaluations show that the proposed scheme is effective and secure. [ABSTRACT FROM AUTHOR]