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Abstract Resilience assessment of civil structures and infrastructure systems plays a vital role in quantitatively measuring the object's ability to withstand and recover from disruptive events (e.g., natural hazards). The performance of the object (structure or system) may degrade with time, and the external loads often display nonstationary characteristics with time‐varying occurrence rate and/or magnitude. In this context, the resilience would be dependent on the duration of the reference period of interest, known as time‐dependent resilience. This article investigates the effect of recovery profile dependency on the time‐dependent resilience of structures and systems. The term “recovery profile dependency” refers to the association of the post‐hazard recovery processes in the aftermath of different load events within the object's service life, and is reflected through the following three aspects: (1) the temporal correlation between the remaining functionalities associated with different load events; (2) the load–recovery interaction (i.e., the scenario that a load event occurs before the full recovery of the degraded functionality due to the previous load event), and (3) the resource allocation strategy in the presence of limited resources, which affects the expeditiousness of each recovery process. In particular, for (2), the concept of average ratio of interaction is proposed to measure the frequency of load‐recovery interaction. The evaluation of time‐dependent resilience is demonstrated through two examples. It is shown that, the time‐dependent resilience is sensitive to the impact of load–recovery interaction and the selection of resource allocation strategy, but is insensitive to the temporal correlation of the remaining functionalities.

Abstract We synthesized a novel, structured lipid containing caprylic acid at its sn‐1,3 position and docosahexaenoic acid at its sn‐2 position (1,3C‐2D‐TAG) by using a two‐step enzymatic method and then investigated the relationship between the types of fatty acids in the structured lipid and their physiological functions. Furthermore, we compared the effects of similarly structured lipids on postprandial lipid metabolism and obesity protection. The results revealed that the novel structured lipid synthesized using the enzymatic method not only exhibited better physical properties than traditional oils but also had high oxidation stability and crystallization degree. In terms of physiological function, the low‐dose 1,3C‐2D‐TAG group exhibited higher cholesterol and triglyceride levels, lower kidney weight or body weight, and higher serum aspartate aminotransferase and blood urea nitrogen levels than control group, whereas the high‐dose 1,3C‐2D‐TAG group exhibited higher triglyceride levels. Moreover, the medium‐dose 1,3C‐2D‐TAG group had remarkably higher high‐density lipoprotein cholesterol levels and lower low‐density lipoprotein cholesterol levels than the high‐lipid, control, and 1,2,3C‐TAG groups; however, the cholesterol and triglyceride levels and kidney and liver functions did not differ significantly among these groups. The study results suggest that 1,3C‐2D‐TAG can not only facilitate the effective utilization of the energy supplied by medium‐chain fatty acids but also help overcome difficulties in the absorption of long‐chain polyunsaturated fatty acids.

Abstract Prevention and early intervention are the current focus of treatment for Alzheimer's disease (AD). An increase in reactive oxygen species (ROS) is a feature of the early stages of AD, thus suggesting that the removal of excess ROS can be a viable method of improving AD. Natural polyphenols are able to scavenge ROS and thus promising for treating AD. However, some issues need to be addressed. Among them, important are that most polyphenols are hydrophobic, have low bioavailability in the body, are easily degraded, and that single polyphenols have insufficient antioxidant capacity. In this study, we employed two polyphenols, resveratrol (RES) and oligomeric proanthocyanidin (OPC), and creatively grafted them with hyaluronic acid (HA) to form nanoparticles to address the aforementioned issues. Meanwhile, we strategically grafted the nanoparticles with the B6 peptide, enabling the nanoparticles to cross the blood–brain barrier (BBB) and enter the brain for AD treatment. Our results illustrate that B6‐RES‐OPC‐HA nanoparticles can significantly scavenge ROS, reduce brain inflammation, and improve learning and memory ability in AD mice. B6‐RES‐OPC‐HA nanoparticles have the potential to prevent and alleviate early AD.

Fibroblastic reticular cells (FRCs) construct microanatomical niches that support lymph node (LN) homeostasis and coordination of immune responses. Transcription factors regulating the functionality of FRCs remain poorly understood. Here, we investigated the role of the transcription factor SpiB that is expressed in LN FRCs. Conditional ablation of SpiB in FRCs impaired the FRC network in the T-cell zone of LNs, leading to reduced numbers of FRCs and altered homeostatic functions including reduced CCL21 and interleukin-7 expression. The size and cellularity of LNs remained intact in the absence of SpiB but the space between the reticular network increased, indicating that although FRCs were reduced in number they stretched to maintain network integrity. Following virus infection, antiviral CD8 + T-cell responses were impaired, suggesting a role for SpiB expression in FRCs in orchestrating immune responses. Together, our findings reveal a new role for SpiB as an important regulator of FRC functions and immunity in LNs., (© 2024 The Authors. Immunology & Cell Biology published by John Wiley & Sons Australia, Ltd on behalf of the Australian and New Zealand Society for Immunology, Inc.)