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As a frontier method for adjusting the electronic and geometric configurations of metal sites, lattice strain engineering plays a key role in regulating the interaction between catalytic surface and adsorbed molecules. Here, the research progress of strain effects in electrochemical carbon dioxide reduction (CO2RR) is reviewed. Starting from the basic principles of strain effects in the CO2RR, the advanced in situ characterization techniques are summarized. The key effect of strain on the structure–activity relationship in CO2RR is comprehensively discussed. Subsequently, the electrocatalysts with different properties rich in strain are classified, including core–shell structure catalysts, alloys, transition metal compounds, and single‐atom catalysts. Finally, the obstacles encountered in the practical application of strain effect are proposed, and the future research direction of this emerging field is prospected. [ABSTRACT FROM AUTHOR]

Objective: To examine the relationship between C‐reactive protein (CRP) and knee pain, and further explore whether this association is mediated by obesity. Methods: The population was derived from 1999 to 2004 National Health and Nutrition Examination Survey. Logistic regression was used to analyze the relationship between CRP and knee pain in three different models, and the linear trend was analyzed. A restricted cubic spline model to assess the nonlinear dose−response relationship between CRP and knee pain. Mediation analyses were used to assess the potential mediating role of obesity. Subgroup analyses and sensitivity analyses were performed to ensure robustness. Results: Compared with adults with lower CRP (first quartile), those with higher CRP had higher risks of knee pain (odds ratio 1.39, 95% confidence interval 1.12−1.72 in third quartile; 1.56, 1.25−1.95 in fourth quartile) after adjusting for covariates (except body mass index [BMI]), and the proportion mediated by BMI was 76.10% (p <.001). BMI and CRP were linear dose−response correlated with knee pain. The odds ratio for those with obesity compared with normal to knee pain was 2.27 (1.42−3.65) in the first quartile of CRP, 1.99 (1.38−2.86) in the second, 2.15 (1.38−3.33) in the third, and 2.92 (1.72−4.97) in the fourth. Conclusion: Obesity mediated the systemic inflammation results in knee pain in US adults. Moreover, higher BMI was associated with higher knee pain risk in different degree CRP subgroups, supporting an important role of weight loss in reducing knee pain caused by systemic inflammation. [ABSTRACT FROM AUTHOR]

Fish in natural and cultivated environments can be challenged by starvation. However, inducing starvation in a controlled manner cannot only reduce feed consumption but also reduces aquatic eutrophication and even improves farmed fish quality. This study investigated the effects of starvation on the muscular function, morphology, and regulatory signaling in javelin goby (Synechogobius hasta) by evaluating the biochemical, histological, antioxidant, and transcriptional changes in the musculature of S. hasta subjected to 3, 7, and 14 days fasting. The muscle glycogen and triglyceride levels in S. hasta were gradually reduced under starvation, reaching their lowest at the end of the trial (P < 0.05). The levels of glutathione and superoxide dismutase were significantly elevated after 3–7 days of starvation (P < 0.05), but later returned to the level of the control group. The muscle of starved S. hasta developed structural abnormalities in some areas after 7 days of food deprivation, and more vacuolation and more atrophic myofibers were observed in 14-day fasted fish. The transcript levels of stearoyl-CoA desaturase 1 (scd1), the key gene involved in the biosynthesis of monounsaturated fatty acids, were markedly lower in the groups starved for 7 or more days (P < 0.05). However, the relative expressions of genes associated with lipolysis were decreased in the fasting experiment (P < 0.05). Similar declines in the transcriptional response to starvation were found in muscle fatp1 and ppar γ abundance (P < 0.05). Furthermore, the de novo transcriptome of muscle tissue from the control, 3-day and 14-day starved S. hasta generated 79,255 unigenes. The numbers of differentially expressed genes (DEGs) identified by pairwise comparisons among three groups were 3276, 7354, and 542, respectively. The enrichment analysis revealed that the DEGs were primarily involved in metabolism-related pathways, including ribosome, TCA pathway, and pyruvate metabolism. Moreover, the qRT-PCR results of 12 DEGs validated the expression trends observed in the RNA-seq data. Taken together, these findings demonstrated the specific phenotypical and molecular responses of muscular function and morphology in starved S. hasta, which may offer preliminary reference data for optimizing operational strategies incorporating fasting/refeeding cycles in aquaculture. [ABSTRACT FROM AUTHOR]

Efficient, facile, lightweight, and low‐frequency sound‐absorbing materials are in great demand for noise elimination and insulation. However, the applications of some candidate materials are limited by their large space, mass, or unsatisfactory sound‐absorption performance especially in low‐frequency sound‐wave region. Graphene network structure can be promising sound‐absorbing materials due to ultrahigh porosity, ultralight weight, and excellent intrinsic properties. Conventionally, allowing for poor mechanical strength, such graphene materials are needed to be reinforced by polymer, metal, or ceramic. Here, a novel strategy of graphene network reinforced by honeycomb structure is proposed, in which graphene is used as a sound absorber, and meanwhile flexible aramid honeycomb is introduced to enhance the graphene composite. In this work, the compressive strength of graphene network structure is improved 1000 times by the flexible aramid honeycomb, and meanwhile the density is only increased 2.5 times. Moreover, the sound‐absorption coefficient of graphene network is about 0.9 at 700 Hz for the thickness of 30 mm. Further, the sound‐absorption coefficient is above 0.9 in the frequency range of >1000 Hz. Therefore, the graphene composite is expected to be saving space and weight for the engineering design of sound absorbers in low‐frequency regions. [ABSTRACT FROM AUTHOR]

Summary: In this article, the problem of finite‐time attitude‐tracking control for rigid spacecraft is addressed. Uncertainties caused by external disturbances, unknown inertial matrix, actuator failures, and saturation constraints are tackled simultaneously. First, a smooth function that is more qualified to approximate the standard saturation characteristics is presented to deal with the actuator saturation constraints. Second, a fast nonsingular terminal sliding mode (FNTSM) manifold is constructed as a foundation of controllers design. By incorporating the fuzzy logic system into FNTSM technique, a less demanding solution of coping with model uncertainties is provided because the requirement of a prior knowledge of unknown inertial parameters and external disturbances in many existing achievements is removed. To reduce the number of parameters to be estimated, the norm approximation approach is exploited. Subsequently, an antichattering attitude controller is presented such that all the tracking errors converge into arbitrary small domains around the origin in finite time. The result is further extended to obtain a fault‐tolerant controller against completely failed actuators. Finally, numerical simulation is conducted to verify the effectiveness of the proposed control scheme and comparison with relevant literature demonstrates its high performance. Furthermore, an experiment for the large satellite Hubble Space Telescope is carried out to validate the practical feasibility. [ABSTRACT FROM AUTHOR]

Background. It is important to distinguish the classification of lung adenocarcinoma. A radiomics model was developed to predict tumor invasiveness using quantitative and qualitative features of pulmonary ground-glass nodules (GGNs) on chest CT. Materials and Methods. A total of 599 GGNs [including 202 preinvasive lesions and 397 minimally invasive and invasive pulmonary adenocarcinomas (IPAs)] were evaluated using univariate, multivariate, and logistic regression analyses to construct a radiomics model that predicted invasiveness of GGNs. In primary cohort (comprised of patients scanned from August 2012 to July 2016), preinvasive lesions were distinguished from IPAs based on pure or mixed density (PM), lesion shape, lobulated border, and pleural retraction and 35 other quantitative parameters (P <0.05) using univariate analysis. Multivariate analysis showed that PM, lobulated border, pleural retraction, age, and fractal dimension (FD) were significantly different between preinvasive lesions and IPAs. After logistic regression analysis, PM and FD were used to develop a prediction nomogram. The validation cohort was comprised of patients scanned after Jan 2016. Results. The model showed good discrimination between preinvasive lesions and IPAs with an area under curve (AUC) of 0.76 [95% CI: 0.71 to 0.80] in ROC curve for the primary cohort. The nomogram also demonstrated good discrimination in the validation cohort with an AUC of 0.79 [95% CI: 0.71 to 0.88]. Conclusions. For GGNs, PM, lobulated border, pleural retraction, age, and FD were features discriminating preinvasive lesions from IPAs. The radiomics model based upon PM and FD may predict the invasiveness of pulmonary adenocarcinomas appearing as GGNs. [ABSTRACT FROM AUTHOR]

The objective of this paper is to investigate the synchronization for nonlinear time-delayed coupling complex dynamic networks with different dimensional nodes through the use of decentralized dynamic compensation controllers. We propose a nonlinear time-delayed coupling complex dynamic network model with similar nonlinear nodes, whose dimensions admit differences. For this kind of network model, based on Barbalat's lemma, decentralized dynamic compensation controllers are designed for the state synchronization of the coupled nodes under some mathematical conditions. In addition, the synchronization manifold is defined as an invariant manifold, which is regarded as the generalized case of the networks with the same node dynamics. Finally, numerical examples with chaotic and hyperchaotic nodes are presented to verify the effectiveness of our theoretical results. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) play important roles in tissue regeneration due to their self-renewal, multilineage differentiation and immunosuppression abilities. MSCs can be isolated from various kinds of tissue, such as umbilical cord, cord blood and placenta. Human placenta mesenchymal stem cells (hPMSCs) possess stronger immunosuppressive properties, such as the ability to inhibit T-cell activation and proliferation, than human bone marrow MSCs. We have investigated that the roles of the programmed death ligands 1 and 2 (PDL1 and PDL2) in hPMSC adhesion, migration and immunosuppression were investigated. PDL1 and PDL2 were highly expressed by hPMSCs. Knockdown of PDL1 and/or PDL2 by siRNA increased hPMSC adhesion, but greatly decreasing migration. PDL1 and PDL2 expressed on hPMSCs inhibited T-cell proliferation by arresting the cell cycle. Knockdown of PDL1 and/or PDL2 in hPMSCs, however, had no effect on the expression of CD69, a T-cell early activation marker found on both CD4+ and CD8+ T-cell subsets. In summary, the roles of the negative co-stimulators PDL1 and PDL2 is on the adhesion, migration and immunosuppression of hPMSCs. These findings may be useful regarding the potential use of hPMSCs in clinical cell. [ABSTRACT FROM AUTHOR]

SUMMARY This paper poses and solves a new problem of state feedback stabilization for a class of high-order stochastic nonlinear systems in which the power order restriction and growth condition are relaxed to a more general form. Based on the ideas of the homogeneous systems theory and the adding of a power integrator technique, a state feedback controller is constructed to ensure that the equilibrium at the origin of the closed-loop system is globally asymptotically stable in probability and that the problem of inverse optimal stabilization in probability is solved. The efficiency of the state feedback controller is demonstrated by a simulation example. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Filtration is the separation of solid–liquid mixtures. In this study, we assess the predictive power of Kozeny–Carman model for systems operated at low Reynolds numbers and relatively high pressure drops. We find substantial agreement between the K‐C model and experiment only for systems that exhibit tight void size distribution. Dramatic disagreement is observed for particle beds that exhibit wide void size distributions. We propose a modified modeling approach, based on a bimodal void distribution, by introducing two quantities: the fraction of expanded voids and the ratio of void sizes. The simulation results are found to be much more similar to the experimental flow rates than those calculated using the K‐C model. The modified model is deemed reliable at predicting the flow behavior, provided that an accurate representation of the void size distribution is available. [ABSTRACT FROM AUTHOR]