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Structure plays a vital role in determining materials properties. In lithium ion cathode materials, the crystal structure defines the dimensionality and connectivity of interstitial sites, thus determining lithium ion diffusion kinetics. In most conventional cathode materials that are well-ordered, the average structure as seen in diffraction dictates the lithium ion diffusion pathways. Here, we show that this is not the case in a class of recently discovered high-capacity lithium-excess rocksalts. An average structure picture is no longer satisfactory to understand the performance of such disordered materials. Cation short-range order, hidden in diffraction, is not only ubiquitous in these long-range disordered materials, but fully controls the local and macroscopic environments for lithium ion transport. Our discovery identifies a crucial property that has previously been overlooked and provides guidelines for designing and engineering cation-disordered cathode materials. The average crystal structure largely governs the Li diffusion kinetics in well-ordered cathode materials. Here the authors show this rule does not hold true for cation-disordered analogues. Cation short-range order is not only ubiquitous but also controls the Li transport behavior.

This review delves into the surface modification of MXenes, underscoring its pivotal role in improving their diverse physicochemical properties, including tailor MXenes’ electrical conductivity, mechanical strength, and wettability. It outlines various surface modification strategies and principles, highlighting their contributions to performance enhancements across diverse applications, including energy storage and conversion, materials mechanics, electronic devices, biomedical sciences, environmental monitoring, and fire-resistant materials. While significant advancements have been made, the review also identifies challenges and future research directions, emphasizing the continued development of innovative materials, methods, and applications to further expand MXenes’ utility and potential.

There has been considerable discussion about the role of cohabitation in family formation since the rise of cohabitation trends in Western societies. However, empirical evidence on how cohabitation-initiated partnership-parenthood trajectories unfold within specific cohorts remains limited. This study aims to identify typical partnership-parenthood trajectories following cohabitation as a first union in young adulthood and to examine how the likelihood of entering each trajectory varies by sociodemographic characteristics. We used data from the National Longitudinal Survey of Youth 1997 (NLSY97) to construct 60-month partnership-parenthood sequences after cohabitation as a first union. We applied sequence analysis and cluster analysis to identify typical patterns and estimated multinomial logistic regression models to examine the associations between sociodemographic characteristics and cluster membership. We identified six typical partnership-parenthood trajectories among young cohabiters. College-educated cohabiters were more likely to enter the marriage-bound trajectory with delayed childbearing. Racial/ethnic minorities were less likely to enter trajectories involving eventual marriage and were overrepresented in trajectories characterized by non-marital birth and relationship instability. Our findings show that there is no single dominant partnership-parenthood pattern, indicating that cohabitation remains a liminal space between singlehood and marriage for the NLSY97 cohort. Sociodemographic differences are more pronounced in entry into certain trajectories than into others.

Exposure to pregnancy during the postpartum period is shaped by biological and behavioral determinants, such as resumption of sexual activity, return of menses, and contraceptive use dynamics. We implement sequence and cluster analyses to generate new insights about exposure to pregnancy during the postpartum period using unique longitudinal data in a low-resource setting. We used population-based data from a sample of 1,935 Ethiopian women who provided reports on factors influencing exposure to pregnancy in the year following childbirth. We used sequence and cluster analyses to characterize patterns of women's reproductive behaviors during the postpartum period. We identified five postpartum trajectories of exposure to pregnancy: (1) no sex; (2) family-planning adopters, no menses; (3) family-planning adopters, return of menses; (4) sex, no menses, no family planning; and (5) sex, menses, no family planning. The 'sex, no menses, no family planning' cluster (50% of the sample) was characterized by resumption of sexual activity around three months postpartum, amenorrhea, and no contraceptive adoption. Women in the two 'family-planning adopters' clusters (39%) resumed sexual activity and adopted contraception around three months postpartum but differ by return of menses. The 'no sex' cluster (5%) was characterized by no sexual activity, contraceptive use, or menses.

Although long neglected, the themes of inequality and the differentiating consequences of structurally organized constraints and opportunities for individuals have recently become a major theme of scholars in aging and life-course studies. Beyond the evidence of intracohort patterns of cumulative dis/advantage in health and resources, recent societal trends of increasing inequality have added another dimension of theoretical interest and practical urgency to these concerns. These trends have been noteworthy both for the dramatic increase and for their planetary breadth, affecting Asia and Europe as well as America. Both researchers and popular writers have observed the growing importance of the precariat, an emerging subpopulation with tenuous connection to the primary economy encompasses individuals of every age. At the same time, individual agency and related concepts such as “choice” and “decision-making” continue regularly to appear as featured terms in studies of life course and related fields. Such concepts accord a strong explanatory force to the individual, and continue to be widely accepted as unproblematic and legitimate. This article examines the relevance of these two domains of life-course scholarship in analyzing an urgent contemporary problem—struggles associated with the “transition to adulthood” and the situation of young adults. Young people confronting this transition have been the focus of both the celebration of agency and of the growing attention on inequality and adversity and its effects on vulnerable periods and key transitions in the life course. Their situation provides an opportunity to resolve some of the tensions between perspectives that emphasize agency and those that emphasize inequality.

In this study, an improved method combining natural surfactants with a solvent–antisolvent precipitation technique was developed to prepare highly effective nano-sized tangeretin particles. Various natural surfactants were tested and compared, and the formulation was optimized using Plackett–Burman and Box–Behnken design methodologies. The optimal preparation conditions were identified as follows: a tangeretin–dimethyl sulfoxide (DMSO) solution concentration of 5.23 mg/mL, surfactant concentration of 4.72%, and a rotor diameter of 20 mm. Under these conditions, uniform nano-tangeretin particles with an average size of 428.73 ± 30.25 nm were successfully produced. The preparation process significantly reduced particle size without chemical structure of tangeretin, as confirmed by spectral analysis. Importantly, the free radical scavenging activity of the nano-tangeretin was markedly enhanced, showing 65.4% increase in DPPH radical inhibition compared to the unprocessed powder. These results demonstrate that the proposed method can improve the bioactivity and dispersibility of tangeretin, providing a valuable strategy for the efficient utilization and industrial-scale production of bioactive compounds from natural resources.

Aiming at the portfolio problem of gold and bitcoin with a given linear trading commission, this paper puts forward the stage implementation forecast and optimal portfolio model. In the aspect of data prediction, SMA is used to predict the initial data, LSTM is used to predict the price trend of long-term data, and daily updated real-time price data is predicted. Considering the risk aversion of investors, the heuristic algorithm is used to solve the daily trading strategy of maximizing utility from September 12th, 2016 to September 12th, 2021. The simulation analysis of the sliding window shows that the algorithm can realize reasonable prediction, which verifies the effectiveness of the algorithm.

According to historical information, more than 300 metal smelting enterprises have been in the southwest of Xiongan for 300 years; however, these polluting enterprises have been gradually closed with the increased intensity of environmental protection. In the paper, 264 soil samples were collected and analyzed in the range of 400 nm–2500 nm by the spectra vista corporation (SVC), and the spectral noise was smoothed by the Savitzky–Golay filter. In order to enhance the spectral differences and curve shapes, mathematical transformations, such as the standard normal variate (SNV), first-order differential (FD), second-order differential (SD), multiple scattering correction (MSC), and continuum removal (CR), were performed on the data, and the correlation between spectral transformation and contents of REEs was analyzed. Moreover, three machine learning models—partial least-squares (PLS), random forest (RF), back propagation neural network (BPNN)—were used to predict the contents of REEs. Experimental results prove that REEs are combined with spectral active substances, such as organic compounds, clay minerals, and iron oxide, and it is possible to determine the contents of REEs using the reflection spectrum. The R2 between the predicted values and measured contents reached 0.986 by using BPNN after FD transformation. More importantly, the predicted values basically agree with the actual situation for CASI/SASI airborne hyperspectral images, and this is an effective technique to obtain the contents of REEs in soil at the study area.

Periodontal disease, a common inflammatory disease, is considered a hazardous factor that contributes to the development of diseases of the digestive system as well as other systems. The bridge between periodontitis and systemic diseases is believed to be periodontal pathogens. The intestine, as part of the lower gastrointestinal tract, has a close connection with the oral cavity. Within the intestine, the intestinal barrier acts as a multifunctional system including microbial, mucous, physical and immune barrier. The intestinal barrier forms the body’s first line of defense against external pathogens; its breakdown can lead to pathological changes in the gut and other organs or systems. Reports in the literature have described how oral periodontal pathogens and pathobiont-reactive immune cells can transmigrate to the intestinal mucosa, causing the destruction of intestinal barrier homeostasis. Such findings might lead to novel ideas for investigating the relationship between periodontal disease and other systemic diseases. This review summarizes studies on the effects of periodontal pathogens on the intestinal barrier, which might contribute to understanding the link between periodontitis and gastrointestinal diseases.

This study focused on the engineering properties of alkali-activated slag (AAS) pastes prepared by mixing an activator consisting of sodium silicate and sodium hydroxide at room temperature. The water-to-slag ratio of AAS paste was kept constant at 0.35 by mass. AAS pastes were prepared using the activator with five different silicate moduli of 1, 1.2, 1.4, 1.6, and 1.8 and three different Na2O contents of 6%, 8%, and 10%. The results showed that both the silicate moduli and Na2O contents had significant effects on the engineering properties of AAS pastes. All the AAS pastes exhibited properties such as fast setting, good workability, and high early compressive strength. The final setting time varied from 9 to 36 min, and the fluidity was in the range of 147–226 mm. The 1 d compressive strength of all the AAS pastes, which could be easily achieved, had values above 55 MPa, whereas the highest strength obtained was 102 MPa with the silicate modulus of 1 and Na2O content of 8% at room temperature. The drying shrinkage increased as the silicate modulus increased. Furthermore, the hydration products and microstructures of AAS pastes were explained according to the microanalysis methods.