The relationship between mindfulness and suboptimal health status: a chain/serial mediation model

BackgroundSuboptimal health status (SHS) represents a third state between health and disease and often progresses into chronic conditions, negatively impacting an individual’s well-being. Studies have shown that mindfulness has a beneficial effect on various SHS symptoms. This study aims to explore the influence of mindfulness on SHS and its underlying mechanisms, with a particular focus on examining the mediating roles of stress and social support.MethodsA total of 173 healthy Chinese college or graduate students, with an average age of 21.85 years, participated in this study. Measurements were taken using the Five Factor Mindfulness Questionnaire, the Sub-Health Measurement Scale, the Perceived Stress Scale, and a self-constructed scale that included demographic information. The PROCESS plugin for SPSS was used to assess mediating effects.ResultsSignificant correlations were found among SHS, social support, mindfulness, and perceived stress (|r| = 0.38–0.85, p < 0.01). Specifically, mindfulness showed a significant positive correlation with SHS and social support (r = 0.38–0.77), while perceived stress was significantly negatively correlated with mindfulness, social support, and SHS (|r| = 0.45–0.85). Perceived social support was positively associated with SHS (r = 0.65). Furthermore, social support and perceived stress partially mediated the influence of mindfulness on SHS. Additionally, a sequential mediation effect of perceived social support and stress in the relationship between mindfulness and SHS was supported.ConclusionThe cultivation of trait mindfulness may be advantageous for individuals’ sub-health. Perceived social support and perceived stress are important underlying mechanisms contributing to this effect

Catalysis on singly dispersed bimetallic sites

A catalytic site typically consists of one or more atoms of a catalyst surface that arrange into a configuration offering a specific electronic structure for adsorbing or dissociating reactant molecules. The catalytic activity of adjacent bimetallic sites of metallic nanoparticles has been studied previously. An isolated bimetallic site supported on a non-metallic surface could exhibit a distinctly different catalytic performance owing to the cationic state of the singly dispersed bimetallic site and the minimized choices of binding configurations of a reactant molecule compared with continuously packed bimetallic sites. Here we report that isolated Rh1Co3 bimetallic sites exhibit a distinctly different catalytic performance in reduction of nitric oxide with carbon monoxide at low temperature, resulting from strong adsorption of two nitric oxide molecules and a nitrous oxide intermediate on Rh1Co3 sites and following a low-barrier pathway dissociation to dinitrogen and an oxygen atom. This observation suggests a method to develop catalysts with high selectivity

Effect of Resveratrol on Mitochondrial Biogenesis and Muscle Fiber Type Transformation in Bovine Myotubes via SIRT1/PGC-1α

This study investigated the effect of resveratrol on muscle fiber type transformation in bovine myotubes. Cell viability and related metabolic enzyme activities were measured by methyl thiazolyl tetrazolium (MTT) and colorimetric assays, and myogenic regulatory factors (MRFs), myosin heavy chains (MyHCs), and gene and protein expression related to mitochondrial biogenesis were determined. The results showed that resveratrol treatment significantly increased the gene expression of Myf5, Myf6, MyoG, and MyoD (P < 0.05) and promoted the differentiation of bovine myotubes. Resveratrol significantly increased slow MyHC expression and decreased fast MyHC expression, while upregulating the mRNA expression levels of MyHC I and MyHC IIa and downregulating the mRNA expression levels of MyHC IIx and MyHC IIb (P < 0.05). Resveratrol also significantly increased succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) activity and decreased lactic dehydrogenase (LDH) activity (P < 0.05). In addition, resveratrol increased the gene and protein expression levels of silent information regulator 1 (SIRT1), peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α), nucleus respiratory factors-1 (NRF-1), mitochondrial transcription factor A (TFAM) (P < 0.05). Addition of the SIRT1 inhibitor 6-chloro-2,3,4,9-tetrahydro-1H-carbazole-1-carboxamide (EX527) significantly attenuated resveratrol-induced muscle fiber type transformation (P < 0.05), and the promoting effect of resveratrol on the gene and protein expression of SIRT1, PGC-1α, NRF-1, and TFAM (P < 0.05). Taken together, resveratrol can promote mitochondrial biogenesis and consequently muscle fiber type transformation by activating the SIRT1/PGC-1α signaling pathway

The Genomes of Oryza sativa: A History of Duplications

We report improved whole-genome shotgun sequences for the genomes of indica and japonica rice, both with multimegabase contiguity, or almost 1,000-fold improvement over the drafts of 2002. Tested against a nonredundant collection of 19,079 full-length cDNAs, 97.7% of the genes are aligned, without fragmentation, to the mapped super-scaffolds of one or the other genome. We introduce a gene identification procedure for plants that does not rely on similarity to known genes to remove erroneous predictions resulting from transposable elements. Using the available EST data to adjust for residual errors in the predictions, the estimated gene count is at least 38,000–40,000. Only 2%–3% of the genes are unique to any one subspecies, comparable to the amount of sequence that might still be missing. Despite this lack of variation in gene content, there is enormous variation in the intergenic regions. At least a quarter of the two sequences could not be aligned, and where they could be aligned, single nucleotide polymorphism (SNP) rates varied from as little as 3.0 SNP/kb in the coding regions to 27.6 SNP/kb in the transposable elements. A more inclusive new approach for analyzing duplication history is introduced here. It reveals an ancient whole-genome duplication, a recent segmental duplication on Chromosomes 11 and 12, and massive ongoing individual gene duplications. We find 18 distinct pairs of duplicated segments that cover 65.7% of the genome; 17 of these pairs date back to a common time before the divergence of the grasses. More important, ongoing individual gene duplications provide a never-ending source of raw material for gene genesis and are major contributors to the differences between members of the grass family

The relationship between mindfulness and suboptimal health status: a chain/serial mediation model

Background: Suboptimal health status (SHS) represents a third state between health and disease and often progresses into chronic conditions, negatively impacting an individual's well-being. Studies have shown that mindfulness has a beneficial effect on various SHS symptoms. This study aims to explore the influence of mindfulness on SHS and its underlying mechanisms, with a particular focus on examining the mediating roles of stress and social support. Methods: A total of 173 healthy Chinese college or graduate students, with an average age of 21.85 years, participated in this study. Measurements were taken using the Five Factor Mindfulness Questionnaire, the Sub-Health Measurement Scale, the Perceived Stress Scale, and a self-constructed scale that included demographic information. The PROCESS plugin for SPSS was used to assess mediating effects. Results: Significant correlations were found among SHS, social support, mindfulness, and perceived stress (|r| = 0.38-0.85, p < 0.01). Specifically, mindfulness showed a significant positive correlation with SHS and social support (r = 0.38-0.77), while perceived stress was significantly negatively correlated with mindfulness, social support, and SHS (|r| = 0.45-0.85). Perceived social support was positively associated with SHS (r = 0.65). Furthermore, social support and perceived stress partially mediated the influence of mindfulness on SHS. Additionally, a sequential mediation effect of perceived social support and stress in the relationship between mindfulness and SHS was supported. Conclusion: The cultivation of trait mindfulness may be advantageous for individuals' sub-health. Perceived social support and perceived stress are important underlying mechanisms contributing to this effect

Opposing effects of energy migration and cross-relaxation on surface sensitivity of lanthanide-doped nanocrystals

10.1016/j.omx.2021.100104Optical Materials: X1210010

Single atom gold catalysts for low-temperature CO oxidation

Low-temperature CO oxidation is important for both fundamental studies and practical applications. Supported gold catalysts are generally regarded as the most active catalysts for low-temperature CO oxidation. The active sites are traditionally believed to be Au nanoclusters or nanoparticles in the size range of 0.5-5 nm. Only in the last few years have single-atom Au catalysts been proved to be active for CO oxidation. Recent advances in both experimental and theoretical studies on single-atom Au catalysts unambiguously demonstrated that when dispersed on suitable oxide supports the Au single atoms can be extremely active for CO oxidation. In this mini-review, recent advances in the development of Au single-atom catalysts are discussed, with the aim of illustrating their unique catalytic features during CO oxidation. (C) 2016, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved

singleatomgoldcatalystsforlowtemperaturecooxidation

CO低温氧化对于基础研究和实际应用均具有重要意义.自上世纪八十年代日本的 Haruta教授发现氧化物负载金催化剂对 CO氧化的超高活性以来,负载金催化剂受到了广泛关注与深入研究,被认为是目前活性最高的 CO氧化催化剂.在诸多影响 CO氧化活性的因素中,纳米金的粒子尺寸是最重要因素之一.目前主流观点认为对于 CO氧化,纳米金有一个最优尺寸范围,在0.5–5 nm,而 Au原子/离子（Au3＋, Au＋）的活性则低一到两个数量级.因此,一般认为负载金单原子催〈br〉 化剂对于 CO氧化反应的活性要比金纳米粒子和团簇低很多.然而,最近几年的理论与实验研究均表明,金单原子负载于合适的载体上可以显示出与金纳米粒子和团簇相当的活性.本文对这些新进展进行综述,阐述金单原子催化剂对 CO氧化的独特反应性能. Gates教授研究组进行了大量关于正价金对 CO氧化影响的研究,其中包括孤立的金原子（Au＋）.他们的研究发现, CO氧化活性随价态降低而降低,表明正价金对 CO氧化至关重要.此外,他们的研究也表明,孤立金原子对 CO氧化的活性（TOF）比金纳米粒子低一到两个数量级.然而,在他们的研究中,有几个因素可能导致催化剂的低活性.首先,他们一般采用非或弱还原性的载体.而载体的还原性对金催化剂上 CO氧化活性影响非常巨大.另外,他们所用的金原子前驱体为配合物,在催化剂制备与反应过程中配体并没有去除,可能也是导致催化剂活性低的原因之一.与此相反,张涛课题组近期采用氯金酸为前驱体,通过简单的吸附浸渍法制备了一系列负载金单原子催化剂.同时用相同的载体制备了负载金纳米粒子催化剂进行对比,可以排除载体等其它影响因素.对比结果显示,单原子催化剂均显示出与纳米粒子相当的 TOF（单位表面 Au原子）和更高的反应速率（单位重量金）.首先制备了氧化铁负载金单原子催化剂,该催化剂在室温即展现出可观活性, TOF值与2–3 nm金粒子 TOF值相当（~0.5 s–1）.更有趣也更重要的是,该催化剂在高温（200oC以上）展现出非常高的反应稳定性,在200oC反应100 h无失活.在300和400oC反应50 h也无失活发生,为开发高温稳定的金催化剂提供了新途径.其次制备了氧化钴负载金单原子催化剂,该催化剂以0.05%金负载量即可实现室温全转化,其 TOF值高达1.4 s–1.然而该催化剂在达到高活性之前必须首先在反应气氛中进行高温处理,这限制了其实用性.此外,催化剂需经反应气氛活化的原因尚待进一步研究.随之又制备了氧化铈负载金单原子催化剂,对富氢条件下 CO选择氧化不仅具有高活性,而且具有极高的 CO选择性.进一步研究结合理论计算表明,高选择性来自氧化铈负载的金单原子不能解离活化氢,对于氢气氧化活性极低,从而导致 CO氧化的高选择性.理论研究方面也有进展. Camellone等计算发现金原子可以取代 CeO2（111）面上的 Ce原子形成 Au＋并促进 CO氧化.然而该金原子会扩散至氧空位形成带负电荷的 Auδ-,阻止 CO和 O2吸附,因而使催化剂失活.李隽课题组利用从头算分子动力学模拟首次发现氧化铈和氧化钛负载的 Au纳米粒子在 CO氧化过程中可以形成单原子的现象,并将之称为动态单原子催化剂. Yang等则计算了二维材料 BN负载 Au单原子催化 CO氧化并发现反应优先通过三原子 E-R机理进行

Molecular insights into the wettability of antifreeze protein-adsorbed hydrate surface: Application to hydrate anti-agglomeration

Adding kinetic inhibitors (KIs) to prevent hydrate formation or anti-agglomerate agents (AAs) adsorbed on hydrate crystals to suppress particle aggregation are both effective means to eliminate hydrate blockage in pressurized pipelines. Antifreeze proteins (AFPs) are representative KIs that hinder hydrate growth via the interfacial adsorption mechanism. This implies the possibility of interfacial modification and simultaneous anti-aggregation effects, which yet have not been explored. Here molecular dynamics (MD) simulations were employed to determine the possible anti-aggregation performance of AFP. Specifically, we identified larger contact angles, that is, the enhanced hydrophobicity, of AFP-adsorbed CH4 hydrate under the dodecane oil phase. This indicates the possible dual inhibition effects of AFP to ensure oil transportation. However, no significant effects of AFP on wettability were observed in the systems with the CO2 hydrate substrate or gas environment. This contrasting behavior was explained by the differences in the hydrogen-bonding formation and interaction strength between substrates and water droplets, which are strongly influenced by the charged residues of AFP. Additionally, we compared AFP with traditional surfactants and emphasized that the anti-aggregation abilities of additives are intricately linked to their functional group arrangements and inherent structures. Our work provides molecular-level guidance for designing effective hydrate inhibitors with dual performance to ensure flow assuranc

Remarkable Performance of Ir₁/FeO_<i>x</i> Single-Atom Catalyst in Water Gas Shift Reaction

High specific activity and cost effectiveness of single-atom catalysts hold practical value for water gas shift (WGS) reaction toward hydrogen energy. We reported the preparation and characterization of Ir single atoms supported on FeO_<i>x</i> (Ir₁/FeO_<i>x</i>) catalysts, the activity of which is 1 order of magnitude higher than its cluster or nanoparticle counterparts and is even higher than those of the most active Au- or Pt-based catalysts. Extensive studies reveal that the single atoms accounted for ∼70% of the total activity of catalysts containing single atoms, subnano clusters, and nanoparticles, thus serving as the most important active sites. The Ir single atoms seem to greatly enhance the reducibility of the FeO_<i>x</i> support and generation of oxygen vacancies, leading to the excellent performance of the Ir₁/FeO_<i>x</i> single-atom catalyst. The results have broad implications on designing supported metal catalysts with better performance and lower cost