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In recent years, investigating lignin as an alternative carbon fiber precursor has received immense research attention as a way to reduce the cost and replace the unsustainable conventional petroleum-based precursors for carbon fiber production. The predominant challenge for lignin-based carbon fibers is its low mechanical performance compared to conventional ones. In this work, mechanical properties of electrospun lignin carbon fiber mats were shown to be considerably enhanced via alignment of the submicron fibers. Over 60% of the fibers were aligned via a rotating drum collector utilized during fiber production. The main electrospinning parameters, namely electric field, rotating speed, and flow rate were optimized with the Box-Behnken method to enhance mechanical properties with reduced fiber diameter and improved fiber alignment. The optimal electrospinning process parameter was achieved at 2000 rpm collection speed, 80 kV/m electric field, and 440 nl/s flow rate. The lignin carbon fibers produced under the optimized condition exhibited elastic modulus of 3145.47 [+ or -] 917.75 MPa, tensile strength of 18.78 [+ or -] 6.11 MPa, and average fiber diameter of 697.07 [+ or -] 96.41 nm. The analysis on the interactions between electrospinning parameters has laid a solid foundation for the production of high-quality carbon fibers from lignin precursor. KEYWORDS carbon fiber, electrospinning, lignin, mechanical properties, optimization, 1 | INTRODUCTION Carbon fiber (CF) is a predominant material utilized in advanced applications including tissue scaffolds, [1] aerospace, [2] supercapacitors, [3,4] batteries, [5-7] water filtration, [8] and automobile industry [...]

Lack of sleep, whether acute or chronic, is quite common and negatively affects an individual's memory and cognitive function. The question of whether chronic sleep deprivation (CSD) causes cognitive impairment to arise and progress is not well studied. To investigate the effects of CSD on memory and cognition, this study began by establishing a CSD mouse model. Behavioral experiments on animals revealed that CSD induced cognitive behavioral abnormalities reminiscent of Alzheimer's disease. Western blot experiments further demonstrated a considerable increase in amyloid-β (Aβ) expression in the mouse brain following CSD. Meanwhile, the hub gene Prkcg was searched for in the cerebellum using RNA-seq and bioinformatics analysis. PKCγ (Prkcg) expression was significantly reduced, as demonstrated by RT-qPCR and Western blot validations. Additionally, CSD was associated with downregulated CREB expression, decreased expression of the endothelin-converting enzyme (ECE1), and increased phosphorylation of ERK1/2 downstream of PKCγ. These findings suggested that CSD down-regulated PKCγ expression, decreased ECE1 expression, impaired Aβ degradation, and affected the PKCγ/ERK/CREB pathway and the synthesis of memory-related proteins. Overall, this study highlighted how CSD modulated PKCγ-related metabolism, impacting Aβ clearance and the production of memory-related proteins. Such insights are crucial for understanding and preventing sporadic Alzheimer's disease (sAD) associated with CSD. [ABSTRACT FROM AUTHOR]

Individual evacuation decision making has been studied for multiple decades mainly using theory-based approaches, such as random utility theory. This study aims to bridge the research gap that no studies have adopted data-driven approaches in modeling the compliance of hurricane evacuees with government-issued evacuation orders using survey data. To achieve this, we conducted a survey in two coastal metropolitan regions of Florida (Jacksonville and Tampa) during the 2020 Atlantic hurricane season. After preprocessing survey data, we employed three supervised learning algorithms with different complexities, namely, multinomial logistic regression, random forest, and support vector classifier, to predict evacuation decisions under various hypothetical hurricane threats. We found that the evacuation decision is mainly determined by people's perception of hurricane risk regardless of whether the government issued an order; COVID-19 risk is not a major factor in evacuation decisions but influences the destination type choice if an evacuation decision is made. Additionally, past and future evacuation destination types were found to be highly correlated. After comparing the algorithms for predicting evacuation decisions, we found that random forest can achieve satisfactory classification performance, especially for certain categories or when some categories are merged. Finally, we presented a conceptual optimization model to incorporate the data-driven modeling approach for evacuation behavior into a government-led evacuation planning framework to improve the compliance rate. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes (LM) is a Gram‐positive (G+) bacterium that secretes nanoscale membrane vesicles (MVs). LM MVs comprise various bacterial components and may have potential as an antigen or drug‐delivery vehicle; however, the low yield of the LM MVs limits related research. G+‐bacterial MVs germinate from the bacterial plasma membrane and must pass through a thick crosslinked peptidoglycan layer for release. Herein, we aimed to increase the release of MVs by reducing the degree of crosslinking of peptidoglycan. We knocked out two genes related to the longitudinal crosslinking of peptidoglycan, dal and dat, and supplemented the knocked‐out dal gene through plasmid expression to obtain a stably inherited recombinant strain LMΔdd::pCW633. The structure, particle size, and main protein components of MVs secreted by this recombinant strain were consistent with those secreted from the wild strain, but the yield of MVs was considerably increased (p < 0.05). Furthermore, Listeria ivanovii (LI) was found to secrete MVs that differed in the composition of the main proteins compared with those of LM MVs. The abovementioned method was also feasible for promoting the secretion of MVs from the attenuated LM strain and LI wild‐type and attenuated strains. Our study provides a new method to increase the secretion of MVs derived from Listeria that could be extended to other G+ bacteria. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li-S) batteries offer a high theoretical energy density but suffer from poor cycling stability and polysulfide shuttling, which limits their practical application. To address these challenges, we developed a PANI-modified MoS2-NG composite, where MoS2 nanoflowers were uniformly grown on graphene oxide (GO) through PANI modification, resulting in an increased interlayer spacing of MoS2. This expanded spacing exposed more active sites, enhancing polysulfide adsorption and catalytic conversion. The composite was used to prepare MoS2-NG/PP separators for Li-S batteries, which achieved a high specific capacity of 714 mAh g−1 at a 3 C rate and maintained a low capacity decay rate of 0.085% per cycle after 500 cycles at 0.5 C. The larger MoS2 interlayer spacing was key to improving redox reaction kinetics and suppressing the shuttle effect, making the MoS2-NG composite a promising material for enhancing the performance and stability of Li-S batteries. [ABSTRACT FROM AUTHOR]

The impact of Borrelia miyamotoi on human health, facilitated by the expanding geographical distribution and increasing population of Ixodes ticks, remains obscure in the context of global climate change. We employed multiple models to evaluate the effect of global climate change on the risk of B. miyamotoi worldwide across various scenarios. The habitat suitability index of four primary vector tick species for B. miyamotoi, including Ixodes persulcatus, Ixodes ricinus, Ixodes pacificus and Ixodes scapularis, was projected using a boosted regression tree model, considering multiple shared socio‐economic pathway scenarios over various time periods. The modelling analysis reveals that, apart from I. scapularis, future global warming will result in a northward shift in the other three vector tick species and a gradual reduction in suitable habitats. Random forest models indicate consistent changes in B. miyamotoi and its primary tick species, with potential risk areas shrinking and shifting northward, particularly in the eastern USA, northeastern and northern Europe and northeast Asia. These findings highlight the urgent need for enhanced active surveillance of B. miyamotoi infection in primary vector tick species across projected potential risk areas. The effect of climate change on B. miyamotoi distribution might have significant implications for public health decision‐making regarding tick‐borne pathogens. [ABSTRACT FROM AUTHOR]

Sewage sludge requires effective dewatering and high nutrients retention before disposal for agricultural application. Pressurized electro-osmotic dewatering (PEOD) process with low energy consumption can effectively remove water from sludge, but the influences of PEOD process on nutrients for agricultural application still lacks in-depth research. In this study, the influences of PEOD process on nutrients for agricultural application were investigated, including organic matter, nitrogen, phosphorus, potassium and silicon contents. Layered experiments were conducted to investigate the layered variation of nutrients in sludge and to understand the potential change mechanisms. The experimental results showed that PEOD process caused small losses (<10%) of organic matter and total phosphorus (TP) in sludge, but caused 11.2−18.4% loss of total nitrogen (TN). PEOD process also caused 18.6−27.0% loss of total potassium (TK) and over 80% loss of available potassium in sludge, and could weaken the potential salt damage during the agricultural application of sludge. Furthermore, the available phosphorus content of sludge in the anode area increased significantly after the PEOD process, indicating that PEOD process could enhance the phosphorus bioavailability of sludge in the anode area. Besides, PEOD process caused a slight loss of silicon components in sludge, but improved the long-term silicon dissolution and release ability of sludge. This work could expand the knowledge about the influences of PEOD process on sludge nutrients and provide scientific guidance for the agricultural application of PEOD sludge. [ABSTRACT FROM AUTHOR]

Designing metal–organic framework (MOF) materials with high conductivity is crucial for their application in energy storage devices. In this study, a simple process, namely, a one-pot hydrothermal method, was used for simultaneously synthesizing the composite of carbon quantum dots (CQDs) and NiCo-MOF, and the effect of various carbon sources for CQDs was compared. The results showed that it was very necessary to choose an appropriate carbon source for obtaining NiCo-MOF with the expected lower Rs and Rct. Carbon sources significantly affected the morphology of NiCo-MOF, and in turn its specific surface area, pore volume and pore size. Particularly, after introducing CQDs derived from citric acid, the electron cloud density around the metal Co atom in the NiCo-MOF composite became higher, improving electron transfer ability, activating the metal center Co and alleviating polarization. As a result, the obtained NiCo-MOF-CA composite exhibited a capacitance of 1826.8 F g−1 at 1 A g−1, significantly higher than that of NiCo-MOF (1060.3 F g−1). An amplifying circuit model was proposed for explaining the phenomenon. Its cyclic performance also became better, but still left to be further improved. The simple synthesis process might be applied to the preparation of other similar composites. In addition, the conductivity of MOFs was improved by introducing specific conductive additives to alter the electronic structure of the metal atom in active materials, providing an effective strategy for other researchers. [ABSTRACT FROM AUTHOR]