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Locally repairable codes (LRCs), which can recover any symbol of a codeword by reading only a small number of other symbols, have been widely used in real-world distributed storage systems, such as Microsoft Azure Storage and Ceph Storage Cluster. Since binary linear LRCs can significantly reduce coding and decoding complexity, constructions of binary LRCs are of particular interest. The aim of this paper is to construct dimensional optimal binary LRCs with disjoint local repair groups. We introduce a method to connect intersection subspaces with binary LRCs and construct dimensional optimal binary linear LRCs with locality 2b (b ≽ 3) and minimum distance d ≽ 6 by employing intersection subspaces deduced from the direct sum. This method will sufficiently increase the number of possible repair groups of dimensional optimal LRCs, thus efficiently expanding the range of the construction parameters while keeping the largest code rates compared with all known binary linear LRCs with minimum distance d ≽ 6 and locality 2b. [ABSTRACT FROM AUTHOR]

Gallbladder cancer is a rare but fatal malignancy. However, the mechanisms underlying gallbladder carcinogenesis and its progression are poorly understood. The function of m6A modification and its regulators was still unclear for gallbladder cancer. The current study seeks to investigate the function of YTH m6A RNA‐binding protein 1 (YTHDF1) in gallbladder cancer. Transcriptomic analysis and immunochemical staining of YTHDF1 in gallbladder cancer tissues revealed its upregulation compared to paracancerous tissues. Moreover, YTHDF1 promotes the proliferation assays, Transwell migration assays, and Transwell invasion assays of gallbladder cancer cells in vitro. And it also increased tumour growth in xenograft mouse model and metastases in tail vein injection model in vivo. In vitro, UHRF1 knockdown partly reversed the effects of YTHDF1 overexpression. Mechanistically, dual‐luciferase assays proved that YTHDF1 promotes UHRF1 expression via direct binding to the mRNA 3′‐UTR in a m6A‐dependent manner. Overexpression of YTHDF1 enhanced UHRF1 mRNA stability, as demonstrated by mRNA stability assays, and Co‐IP studies confirmed a direct interaction between YTHDF1 and PABPC1. Collectively, these findings provide new insights into the progression of gallbladder cancer as well as a novel post‐transcriptional mechanism of YTHDF1 via stabilizing target mRNA. [ABSTRACT FROM AUTHOR]

A locally repairable code (LRC) is a code that can recover any symbol of a codeword by reading at most r other symbols, denoted by r -LRC. In this paper, we study binary and ternary linear LRCs with disjoint repair groups and minimum distance d = 6. Using the intersection subspaces technique, we explicitly construct dimensional optimal LRCs. First, based on the intersection subspaces constructed by t -spread, a construction of binary LRCs is designed. Particularly, a class of binary linear LRCs with r = 11 is optimal in terms of achieving a sphere-packing type upper bound. Next, by using the Kronecker product of two matrices, two classes of dimensional optimal ternary LRCs with small locality (r = 3, 5) are presented. Compared to previous results, our construction is more flexible regarding code parameters. Finally, we also discuss the parameters of a code obtained by applying a shortening operation to our LRCs. We show that these shortened LRCs are also k -optimal. [ABSTRACT FROM AUTHOR]

Objective: To prepare polylactic acid microneedles (PLAMNs) with sustained antibacterial effect to avoid skin infection caused by traditional MNs-based biosensors. Methods: Silver nanoparticles (AgNPs) were synthesized using an in-situ reduction process with polydopamine (PDA). PLAMNs were fabricated using the hot-melt method. A series of pressure tests and puncture experiments were conducted to confirm the physicochemical properties of PLAMNs. Then AgNPs were modified on the surface of PLAMNs through in-situ reduction of PDA, resulting in the formation of PLAMNs@PDA-AgNPs. The in vitro antibacterial efficacy of PLAMNs@PDA-AgNPs was evaluated using agar diffusion assays and bacterial liquid co-culture approach. Wound healing and simulated long-term application were performed to assess the in vivo antibacterial effectiveness of PLAMNs@PDA-AgNPs. Results: The MNs array comprised 169 tiny needle tips in pyramidal rows. Strength and puncture tests confirmed a 100% puncture success rate for PLAMNs on isolated rat skin and tin foil. SEM analysis revealed the integrity of PLAMNs@PDA-AgNPs with the formation of new surface substances. EDS analysis indicated the presence of silver elements on the surface of PLAMNs@PDA-AgNPs, with a content of 14.44%. Transepidermal water loss (TEWL) testing demonstrated the rapid healing of micro-pores created by PLAMNs@PDA-AgNPs, indicating their safety. Both in vitro and in vivo tests confirmed antibacterial efficacy of PLAMNs@PDA-AgNPs. Conclusions: In conclusion, the sustained antibacterial activity exhibited by PLAMNs@PDA-AgNPs offers a promising solution for addressing skin infections associated with MN applications, especially when compared to traditional MN-based biosensors. This advancement offers significant potential for the field of MN technology. [ABSTRACT FROM AUTHOR]

N6‐methyladenosine (m6A) is the most abundant internal modification in eukaryotic RNA and involved in the carcinogenesis of various malignancies. However, the functions and mechanisms of m6A in gallbladder cancer (GBC) remain unclear. In this study, we investigated the role and underlying mechanism of the RNA‐binding protein YT521‐B homology domain‐containing family protein 2 (YTHDF2), an m6A reader, in GBC. Herein, we detected that YTHDF2 was remarkably upregulated in GBC tissues compared to normal gallbladder tissues. Functionally, YTHDF2 overexpression promoted the proliferation, tumor growth, migration, and invasion of GBC cells while inhibiting the apoptosis in vitro and in vivo. Conversely, YTHDF2 knockdown induced opposite results. Mechanistically, we further investigated the underlying mechanism by integrating RNA immunoprecipitation sequencing (RIP‐seq), m6A‐modified RIP‐seq, and RNA sequencing, which revealed that death‐associated protein kinase 3 (DAPK3) is a direct target of YTHDF2. YTHDF2 binds to the 3′‐UTR of DAPK3 mRNA and facilitates its degradation in an m6A‐dependent manner. DAPK3 inhibition restores the tumor‐suppressive phenotype induced by YTHDF2 deficiency. Moreover, the YTHDF2/DAPK3 axis induces the resistance of GBC cells to gemcitabine. In conclusion, we reveal the oncogenic role of YTHDF2 in GBC, demonstrating that YTHDF2 increases the mRNA degradation of the tumor suppressor DAPK3 in an m6A‐dependent way, which promotes GBC progression and desensitizes GBC cells to gemcitabine. Our findings provide novel insights into potential therapeutic strategies for GBC. [ABSTRACT FROM AUTHOR]

Microneedles (MNs) have recently garnered extensive interest concerning direct interstitial fluid (ISF) extraction or their integration into medical devices for continuous biomarker monitoring, owing to their advantages of painlessness, minimal invasiveness, and ease of use. However, micropores created by MN insertion may provide pathways for bacterial infiltration into the skin, causing local or systemic infection, especially with long-term in situ monitoring. To address this, we developed a novel antibacterial sponge MNs (SMNs@PDA-AgNPs) by depositing silver nanoparticles (AgNPs) on polydopamine (PDA)-coated SMNs. The physicochemical properties of SMNs@PDA-AgNPs were characterized regarding morphology, composition, mechanical strength, and liquid absorption capacity. The antibacterial effects were evaluated and optimized through agar diffusion assays in vitro. Wound healing and bacterial inhibition were further examined in vivo during MN application. Finally, the ISF sampling ability and biosafety of SMNs@PDA-AgNPs were assessed in vivo. The results demonstrate that antibacterial SMNs enable direct ISF extraction while preventing infection risks. SMNs@PDA-AgNPs could potentially be used for direct sampling or combined with medical devices for real-time diagnosis and management of chronic diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: The tumor microenvironment (TME) exhibits a pivotal function in the progression of cancer through the bidirectional communication between cellular and noncellular components. During the exchange and interplay of biological signals between immune cells and tumor cells in TME, exosomal lncRNAs are viewed as one of the vital factors, which can interfere with innate and adaptive immune responses to affect the therapeutic efficiency. This review aims to summarize the advance in the roles of exosomal lncRNAs on tumor-immune regulation and propose potential treatment strategies. Exosomes are nanovesicles secreted into biofluids by various cell types and have been implicated in different physiological and pathological processes. Interestingly, a plethora of studies emphasized the mediating role of exosomes in the bidirectional communication between donor and recipient cells. Among the various cargoes of exosomes, long non-coding RNAs (lncRNAs) have been identified as crucial regulators between cancer cells and immune cells in the tumor microenvironment (TME) that can interfere with innate and adaptive immune responses to affect the therapeutic efficiency. Recently, a few major studies have focused on the exosomal lncRNA-mediated interaction between cancer cells and immune cells infiltrated into TME. Nevertheless, a dearth of studies pertains to the immune regulating role of exosomal lncRNAs in cancer and is still in the early stages. Comprehensive mechanisms of exosomal lncRNAs in tumor immunity are not well understood. Herein, we provide an overview of the immunomodulatory function of exosomal lncRNAs in cancer and treatment resistance. In addition, we also summarize the potential therapeutic strategies toward exosomal lncRNAs in TME. [ABSTRACT FROM AUTHOR]

Although workplace age discrimination research has been recognized as increasingly important, much less agreement has been reached regarding the operationalization and measurement of age discrimination. There are multiple age discrimination scales, yet no systematic investigation of potential convergence across those scales exists. We conducted two investigations of age discrimination scales that differ in multiple measurement characteristics (e.g. content domain). Findings of confirmatory factor analyses from Study 1 (N = 248) indicated that although different age discrimination scales were related to the same higher-order construct, they were not interchangeable as they each accounted for idiosyncratic measurement variance. The usage of different scales resulted in different magnitudes of the relationships between age discrimination and its correlates. In addition to the replication of these results in Study 2 (N = 939), an item response theory approach was applied to demonstrate that different age discrimination scales possess different levels of test information at different places of the latent trait continuum. Taken together, our findings provide implications for researchers to thoughtfully choose their operationalization of age discrimination. [ABSTRACT FROM AUTHOR]

Heterogeneous catalysis is an important way to realize green chemistry. Developing excellent heterogeneous catalysts by using appropriate supports is still a mainstream research area. Polyacrylonitrile fiber (PANF), a common textile material in our daily life, has excellent advantages of low cost, high strength, light density, mildew resistance, etc. Furthermore, PANF can be knitted into varieties of shapes, making them very suitable for fixed‐bed catalysis in industries. Consequently, PANF is a fine raw material for the synthesis of heterogeneous catalysts. Therefore, more and more PANF‐based heterogeneous catalysts had been developed and applied to various of reaction systems. In this paper, the research progress of PANF‐based catalysts was reviewed, and the research progress of different PANF catalytic systems and their applications in green chemistry were emphatically introduced, which provided reference to the development of PANF‐supported catalytic technology. Finally, the catalytic system supported by PANF is summarized and prospected. [ABSTRACT FROM AUTHOR]

Pyroptosis is an inflammatory form of cell death triggered by certain inflammasomes. However, research concerning pyroptosis-related lncRNAs in hepatocellular carcinoma (HCC) remains scarce. This study aims to explore the prognostic pyroptosis-related long non-coding RNAs (lncRNAs) of HCC patients. Data of 373 HCC patients were obtained from the TCGA database. The entire cohort was randomly divided into a training cohort and a validation cohort in a 2:1 ratio. Pyroptosis-related lncRNAs were identified by the Pearson correlation analysis with reported pyroptosis-related genes. LASSO Cox regression was used to construct the signature. A prognostic signature consisting of nine pyroptosis-related lncRNAs was identified, and patients with lower risk scores had a better prognosis than those with higher risk scores. Multivariate Cox regression analysis showed that the signature was an independent risk factor for prognosis in both the training and validation cohorts. In the training cohort, the area under the signature curve reached 0.8043 at 1-year, 0.7878 at 2-year, and 0.8118 at 3-year; in the validation cohort, it reached 0.7315 at 1-year, 0.7372 at 2-year, and 0.7222 at 3-year. Gene set enrichment analysis (GSEA) suggested associations between the signature and several immune-related pathways. The expression of multiple immune checkpoints was also increased in the high-risk group, including PD-1, PD-L1, CTLA4, B7-H3, VSIR, LAG3, and TIGIT. A novel pyroptosis-related lncRNA signature, which may be associated with tumor immunity and potentially serve as an indicator for immunotherapy, has been identified to precisely predict the prognosis of HCC patients. [ABSTRACT FROM AUTHOR]

Heterogeneous catalysis is an important branch of sustainable chemistry. In this work, a series of polyacrylonitrile fiber (PANF) fiber catalysts (PANF-E, PANF-EDs, and PANF-D) with different catalytic micro-environments are developed and characterized by elemental analysis, Fourier-transfer infrared spectroscopy, x-ray diffraction, thermogravimetric/differential scanning calorimetry analysis, scanning electron microscopy, and mechanical strength measurements to demonstrate the successful immobilization of the different amines as well as evaluate the physical strength and thermal stability of the fiber catalysts at different stages. The catalytic activities of the fiber catalysts are tested by one-pot three-component Knoevenagel-Michael reaction to the synthesis of substituted 2-amino-4H-chromenes in which the influences of surface polarities, kinds and proportions of functional groups on the fiber catalysts activities were investigated. Among the prepared catalysts, the PANF-D with higher density of tertiary amino group and hydrophilic micro-environment exhibited the best catalytic activity to efficiently catalyze the three-component reaction in water with excellent substrate suitability (92-98%). In addition, the catalyst can be easily separated from the catalytic system and conveniently reused at least ten times. Moreover, the PANF-D performs well in scaled-up experiment in a simple fixed-bed reactor with a yield of 97% which allows it to have great potential for further cleaner industrial applications. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the adsorption of carbonic acid and water molecules on the (010) surface of γ‐dicalcium silicate (γ‐C2S) at an atomic scale using density functional theory (DFT) and ab initio molecular dynamics. It provides novel insights into the mechanism of carbonation on the surface of γ‐C2S. The electrons transfer and interfacial reactions between the carbonic acid (H2CO3) molecule and the γ‐C2S surface are characterized by adsorption configuration, bond order, electron density difference, and partial density of states. There exist strong interactions between H2CO3 and γ‐C2S surface, including two types of chemical adsorption and one type of physical adsorption. This work confirms that water in the carbonation of γ‐C2S is to react with CO2 to provide the reactants, and protons transfer of the carbonic acid molecule plays a crucial role in the carbonation process. The adsorption of the carbonic acid molecule is more favorable with respect to that of the water molecule, which may be the initial step of the carbonization of γ‐C2S. [ABSTRACT FROM AUTHOR]

Defects causing concomitant loss of CD25 expression in regulatory T cells (Tregs) have been identified in systemic lupus erythematosus (SLE). However, the cause of this deficiency is not fully understood. Carcinoembryonic antigen related cell adhesion molecule 1 (CEACAM1), an immune co‐receptor, contributes to general T‐cell function and activation. Our previous study revealed that CEACAM1 expression was upregulated in peripheral blood mononuclear cells (PBMCs) from patients with SLE. However, its role remains unclear. Herein, we confirmed CEACAM1, especially CEACAM1‐S, was upregulated in PBMCs from patients with SLE. CEACAM1‐S over‐expression inhibits CD4+CD25+ Treg differentiation, whereas knockdown of CEACAM1 had the opposite effect in vitro. CEACAM1‐S is the target of miR‐31. MiR‐31 mimic inhibits CEACAM1 expression and enhances CD4+CD25+ Treg differentiation, which was reversed by CEACAM1‐S over‐expression. Moreover, the circulating TGF‐β level was upregulated in SLE patients and TGF‐β reduced miR‐31 expression via enhancing NF‐κB activity. Importantly, CEACAM1 and TGF‐β mRNA levels were downregulated, while the miR‐31 level and the abundance of CD4+CD25+ Tregs were increased in inactive patients compared with that in patients with active SLE. In addition, CEACAM1‐S expression was positively correlated with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, while CD4+CD25+ Treg abundance and miR‐31 level were negatively correlated with the SLEDAI score. In conclusion, reduced activity of miR‐31 by TGF‐β, via the inhibition of NF‐ᴋB, acted to inhibit the differentiation of CD4+CD25+ Tregs by directly targeting CEACAM1‐S and to promote autoimmunity. [ABSTRACT FROM AUTHOR]

Illustrating the influence of Fe dosage and temperature on the formation of sulfoaluminate hydrates is of great significance to understand the early hydration process of high ferrite cement under steam curing. Herein, the impact of Fe dosage on the ettringite formation at different temperatures was revealed through the combination of experiments and computational simulations. A Fe dosage no more than 20% conspicuously accelerated the crystal growth of ettringite by increasing the surface energy in the (0 0 1) direction, whereas a higher dosage suppressed the formation of ettringite as the high incorporation of Fe ions into the ettringite crystal was energetically unstable. The chemical environment analysis of Fe in products shows that Fe(OH)63−, compared with Al(OH)63−, prefers to participate in the formation of Al2O3‐Fe2O3‐mono than ettringite, which is also confirmed by the calculated thermodynamic properties' results. The understanding of the impact and mechanism of Fe on the formation of ettringite under steam curing conditions plays a pivotal role in the utilization of high ferrite cement. [ABSTRACT FROM AUTHOR]

A series of novel polyacrylonitrile fiber catalysts modified with different ratio of quaternary ammonium salt (QA) to tertiary amine (TA) were screened for heterogeneously catalyzed aza-Michael addition in water. The best catalyst was found to be PANPQ-1F with a QA:TA ratio of 1:1, which can lead to high yield, excellent selectivity of solvent and great recyclability under optimized conditions. The special microenvironment of hydrophilic inner layer and hydrophobic surface layer of PANPQ-1F is conducive to the leaving of the product and the high conversion of the reaction. Based on the fact that appropriate microenvironment combined with the catalytic sites promoted the reaction, cooperative effect of QA and TA in the microenvironment of PANPQ-1F catalyst was proposed. [ABSTRACT FROM AUTHOR]

Previous research suggests that workplace deviance, one of the most pressing problems for today's organizations, tends to decline as employees age. However, little is known about the mechanisms underlying the age-deviance relationship. Using aggregated 5-day daily diary data in a sample of 158 Chinese full-time employees, the present study examined age differences in the use of emotional labor strategies (i.e. surface acting and deep acting) and how these age differences relate to employee workplace deviance via organizational cynicism. Results found that age was negatively related to the use of both surface acting and deep acting. Emotional labor strategies (i.e. surface acting and deep acting) and organizational cynicism serially mediated the relationship between employee age and workplace deviance. The current research deepens our understanding of the process by which employee age relates to workplace deviance. This study also has implications for the management of an increasingly age-diverse workforce and can guide future interventions aiming at reducing workplace deviance, an issue of increasing concern to both organizations and society in general. [ABSTRACT FROM AUTHOR]

Adapting the spillover–crossover model to the context of eldercare, we employed a 5-week weekly diary method in a sample of 82 Chinese dual-earner heterosexual couples to examine the relationships between family eldercare demands, family-to-work conflict, and time theft. Results from multilevel path modeling analyses found that family eldercare demands (as a shared/common stressor) were positively related to each partner's family-to-work conflict and that the weekly family-to-work conflict of each partner was positively related. Furthermore, family eldercare demands were positively related to each partner's time theft at the week level, and this relationship was mediated by weekly family-to-work conflict. Thus, this is one of the first studies to show that family eldercare demands can explain the interindividual crossover of family-to-work conflict between partners at the week level and this can spill over intraindividually to impact time theft at work. These findings enhance the field's understanding of the process by which eldercare demands relate to time theft among dual-earner couples within a focused temporal framework. [ABSTRACT FROM AUTHOR]

Brownmillerite‐type oxides are a large family of structural and functional materials that are of great concern. In this study, the occupancy mechanism of Fe and Al ions in brownmillerite Ca2FeAlO5 is revealed and the specific configuration of Ca2FeAlO5 is proposed for the first time. Through the energy analysis of a series of conjectured models based on well‐defined ab initio calculations, we find that the distribution of Al and Fe in Ca2FeAlO5 follows the "homogeneous layer principle", namely, Al and Fe tend to form homogeneous octahedral layers or tetrahedral chains rather than mixed layers or chains of two elements along the b axis. The theoretical Ca2FeAlO5 structure with specific atomic occupancy is proposed based on energy analysis and previous experiments, which is of fundamental significance for further study of its physical and chemical properties. Moreover, the influence of entropy increment on the stability of Ca2FeAlO5 crystal is clarified, which paves the way to investigate the structures and properties of Ca2FeAlO5 and other brownmillerite members. [ABSTRACT FROM AUTHOR]

Myeloid‐derived suppressor cells (MDSCs) are functionally immunosuppressive cells that are persistently increased in abundance and associated with adverse clinical outcomes in sepsis. Here, we investigated the therapeutic potential of an anaplastic lymphoma kinase inhibitor, LDK378, in cecal ligation and puncture (CLP)‐induced polymicrobial sepsis and examined its effects on the recruitment of MDSCs. LDK378 significantly improved the survival of CLP‐induced polymicrobial septic mice, which was paralleled by reduced organ injury, decreased release of inflammatory cytokines and decreased recruitment of MDSCs to the spleen. Importantly, LDK378 inhibited the migration of MDSCs to the spleen by blocking the CLP‐mediated upregulation of CC chemokine receptor 2 (CCR2), a chemokine receptor critical for the recruitment of MDSCs. Mechanistically, LDK378 treatment blocked the CLP‐induced CCR2 upregulation of MDSCs via partially inhibiting the phosphorylation of p38 and G‐protein‐coupled receptor kinase‐2 (GRK2) in bone marrow MDSCs of septic mice. Furthermore, in vitro experiments also showed that lipopolysaccharide (LPS)‐induced migration of MDSCs was similarly owing to the activation of GRK2 and upregulation of CCR2 by LPS, whereas the treatment with LDK378 partially blocked the LPS‐induced phosphorylation of p38 and GRK2 and decreased the expression of CCR2 on the cell surface, therefore leading to the suppression of MDSC migration. Together, these findings unravel a novel function of LDK378 in the host response to infection and suggest that LDK378 could be a potential therapeutic agent for sepsis. [ABSTRACT FROM AUTHOR]

Molybdenum clusters consisting of 2–55 atoms were investigated using density functional theory calculations with a plane-wave basis set. The results show that the linear and planar molybdenum clusters have a strong tendency to form dimers. This tendency results in the formation of alternate short and long bonds within a linear cluster, in which the strength of these short bonds is covalent. Therefore, the linear and planar Mo clusters exhibit significant nonmetallic characteristics. Furthermore, the linear and planar Mo clusters show a strong even-odd effect in binding energy with the even-numbered clusters being more stable than their neighboring odd-numbered clusters. On the other hand, the even-odd effect in the energy gap between the highest occupied and the lowest unoccupied molecular orbitals, i.e., the HOMO-LUMO energy gap, for the linear and the planar clusters is different. The odd-numbered linear clusters and even-numbered planar clusters have larger HOMO-LUMO energy gaps than their corresponding neighboring clusters. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A systematic investigation of palladium nanoparticles of up to 55 atoms (1.4 nm) has been conducted using density functional theory with a plane wave basis set. The stability of these nanoparticles increases with cluster size and dimensionality. It also depends strongly on the cluster structures through two factors, the coordination numbers of atoms and the strength of the single bonds. Both the energy gap between the highest occupied and the lowest unoccupied molecular orbitals and the magnetic moment change oscillatorily with cluster size. Furthermore, highly magnetic clusters tend to have large energy gaps. Analysis of the atom-resolved magnetic moment reveals that the local magnetism of a cluster depends mainly on the atomic bonding environments. A simple approach is proposed to predict relative stabilities of various structures for larger clusters. In addition, a structure factor is defined to correlate quantitatively various properties of the Pd clusters with their structures. [ABSTRACT FROM AUTHOR]

In this paper, a two-dimensional geometric model is developed to characterise the air-void system in hardened cement paste. This model consists of non-overlapping circular voids of different size classes randomly placed in the cementitious matrix of a specific size. The major output of this model is the distance of a specific void from its nearest neighbour (void–void spacing). The cumulative distribution function of the nearest void–void spacing fits well the Rosin–Rammler model, from which the probability distribution function is derived. The number and distribution of the voids is obtained from the chord length measurement based on the linear-traverse method. The effect of paste content and air-void saturation on the void spacing is investigated to illustrate gradual increase in void spacing with a higher paste content or the partial filling of air voids. This model is validated by the good correlation between the calculated spacing factor and the tensile strain capacity of concrete from length-change measurement. [ABSTRACT FROM AUTHOR]

As a special type of linear codes, minimal linear codes have important applications in secret sharing. Up to now, only a few infinite families of minimal binary linear codes with wmin/wmax≤1/2 were reported in the literature, while vast knowledge exists on the ones with wmin/wmax>1/2. Herein, wmin and wmax respectively denote the minimum and maximum nonzero Hamming weights in a linear code. Recently, several classes of linear codes with certain properties were constructed by Zhou et al. from a generic construction. The objective of this paper is to obtain four families of minimal binary linear codes with wmin/wmax≤1/2 from those linear codes proposed by Zhou et al. The parameters of our minimal linear codes are quite different from known ones. Based on the properties of Krawtchouk polynomials, the weight distributions of all these four families of binary linear codes are established. [ABSTRACT FROM AUTHOR]

Converting renewable biomass and their derivatives into chemicals and fuels has received much attention to reduce the dependence on fossil resources. Photocatalytic ethanol dehydrogenation–acetalization to prepare value‐added 1,1‐diethoxyethane and H2 was achieved over non‐precious metal CdS/Ni‐MoS2 catalyst under visible light. The system displays an excellent production rate and high selectivity of 1,1‐diethoxyethane, 52.1 mmol g−1 h−1 and 99.2 %, respectively. In‐situ electron spin resonance, photoluminescence spectroscopy and transient photocurrent responses were conducted to investigate the mechanism. This study provides a promising strategy for a green application of bioethanol. Remove hydrogen and acetalize: Photocatalytic ethanol dehydrogenation–acetalization to prepare value‐added 1,1‐diethoxyethane and H2 was achieved over non‐precious metal CdS/Ni‐MoS2 catalyst under visible light. This work provides a promising strategy for a green atom‐economic application of bioethanol. [ABSTRACT FROM AUTHOR]

Abstract: Ettringite and thaumasite are 2 of the relevant secondary products in portland cement minerals. They are rare crystals with high water content. Two density functional theory based ab initio packages VASP and the OLCAO were used for exploring the geometry structure, electronic, and mechanical properties of ettringite and thaumasite. The calculations focus on the comparison of their structures and properties to gain insights that can reveal the minute difference in properties due to differences in their structure, composition and water content. Detailed analysis of interatomic bonding shows the similarities and subtle difference between them even though thaumasite has the Si tetrahedron as the backbone unit in contrast to ettringite with Al‐columns and no Si atoms. Moreover, thaumasite has strong C–O bonds that are absent in ettringite, and ettringite has far more water molecules with a substantial contribution from the hydrogen bonding. It is shown that the role played by relatively strong S–O bonds in both crystals has a large impact on the hydration in these crystals. On the basis of calculated total bond order density, it is concluded that thaumasite is slightly more cohesive than ettringite consistent with the calculated mechanical properties. The detailed comparative results for these 2 important minerals we obtained in this paper, many of them for the first time, will pave the way to understanding the structure and electronic structure origin of other more complex cement crystals. [ABSTRACT FROM AUTHOR]

A series of novel dual-responsive BN-embedded phenacenes were designed and synthesized, via N-directed borylation of donor–acceptor–donor (D–A–D) precursors as the key step. Their crystal structures, and photophysical and electrical properties were systematically studied, which were found to be highly dependent on the incorporated BN units and fused aromatic rings with varied electron density. For the first time, mechanochromic luminescent (MCL) properties of BN-embedded phenacenes were realized, which are regulated jointly by inter- and intra-molecular effects at the molecular level. In the solid state, their emission colors can be tuned reversibly by external force, and interestingly, they exhibit an unusual hypochromic shift after grinding. Furthermore, in solution, these BN-containing phenacenes enable colorimetric and fluorometric detection of fluoride ions with high selectivity and a low detection limit of down to 1.8 × 10−8 M. The dual-responsive properties of these compounds highlight the widespread applications of BN containing conjugated materials in optical sensors. [ABSTRACT FROM AUTHOR]

In this work, we have synthesized a novel hemicyanine-modified polyacrylonitrile fiber (HDBA-PANAF) as a colorimetric Hg2+ sensor. The color is observed from dark red to orange by the naked eye only when the fiber is exposed to Hg2+. Positively, the HDBA-PANAF shows high selectivity and sensitivity for Hg2+ compared with other metal ions such as Na+, Mg2+, Al3+, Ca2+, Cr3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Ag+, Cd2+ and Pb2+. Furthermore, the obtained fiber has a wide pH application range from 3 to 11 and also processes a lower detection limit of 1 × 10−6 mol L−1 for Hg2+. Moreover, the HDBA-PANAF undergoes an obvious color change toward Hg2+ even containing an excess of ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) in the solution, indicating that the fiber has a stronger complexation affinity for Hg2+ than EDTA-2Na. Hence, the fiber sensor possesses the merits of low cost, high selectivity, low detection limit and environment-friendly property, which shows that it is a promising candidate for Hg2+ detection in water. [ABSTRACT FROM AUTHOR]

Featured Application: The photocatalysis could be used for water treatment and other environmental engineering. Ag and Au nanoparticles (NPs) were decorated on the surface of TiO2 membranes by two methods, i.e., hydrothermal synthesis and photoreduction. The size of Ag and Au NPs on the surface of TiO2 membranes was dependent on the method of preparation and varied from 2 nm–10 nm. The photocatalytic performance of the TiO2 particle, TiO2 membrane and the Ag/Au-decorated TiO2 membrane was tested for the catalytic degradation of Rhodamine B (RhB) and Escherichia coli (E. coli) under irradiation of visible light. The experiment results showed that both Ag- and Au-decorated TiO2 membranes exhibited excellent photocatalytic activity in the visible light region. Among the prepared materials, Ag-decorated TiO2 membranes prepared by photoreduction showed the highest activity, which could be attributed to the local surface plasmon resonance (LSPR) effect of the noble metal. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the doping behavior of impurity ions in clinker phases is crucial for controlling the doping effect on clinker compounds, which, however, has not yet been fully demonstrated due to the composition complexity. Herein, we employ the state‐of‐the‐art ab initio calculation to uncover the substitution mechanism of Cu ions in 4 dominant clinker crystals. The defect formation energies indicate Cu ions energetically prefer to substitute Fe ions in ferrite, which is in accord with the experiments. The bond order difference is innovatively postulated to interpret the energy barriers of Cu substitution in comparison with the ionic radius criterion. The high potential barriers of Cu substituting Ca, Si, and Al ions are ascribed to their bond order mismatch, while the tendency of Cu replacing Fe is due to their bond order similarity. Namely, the Cu doping in clinker phases follows the “bond order conformity” principle. In‐depth electronic structure analysis reveals that the bond order is more effective than the ionic radius to estimate potential barriers of Cu substitution in complex clinker system mainly because the latter underestimates the influence of electronic structure differences while the bond order directly measures the bonding structure related to interatomic charge transfer. [ABSTRACT FROM AUTHOR]

ABSTRACT A polyacrylonitrile fiber catalyst with high polar surface micro-environment (C-PANF-Na) was conveniently synthesized and characterized by elemental analysis, Fourier-transfer infrared spectroscopy, UV-vis spectroscopy, scanning electron microscopy, X-ray diffraction, and breaking strength test. The catalytic performance of the fiber was tested by Henry reaction and Gewald reaction in water and favorable results were obtained in terms of high yields, mild conditions, extensive applicability, superior catalytic recyclability, and renewability. It also has advantages of easy preparation, high functional degree, good stability in acid and base, high strength, and good flexibility, and so on. In addition, a high solvent selectivity phenomenon was found in this catalytic system and the reason was explained by proposing a high polar micro-environment effect. Furthermore, the fiber catalyst performed well in scaled-up experiment and flow chemistry experiment, which shows tremendous potential in industrial catalyst as an ideal material for packed bed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45992. [ABSTRACT FROM AUTHOR]

Abstract: The l-lysine functionalized polyacrylonitrile fiber (PANLF) was prepared by grafting the l-lysine into a commercially available polyacrylonitrile fiber and showed highly catalytic activity for Knoevenagel condensation reaction. With low temperature (45 °C) and short reaction time (1 h), the fiber catalyst was well applicable to Knoevenagel condensation of a wide range of aldehydes and the yields could reach up to 99%. Interestingly, only in water could the reaction take place smoothly (with a yield of 88%) and a polar micro-environment promoted reaction process had been proposed to explain this phenomenon. Besides, the fiber catalyst has advantages of easy preparation, high functional degree, strong mechanical strength and thermal stability, etc. And it can be reused at least 5 times without further treatment and performed well in scaled-up experiment (amplified 50 times) and flow chemistry experiment (no loss of catalytic activity after 48 h), which indicates its potential application in industry application.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The preparation and application of fiber catalysts have attracted much attention. However, research on the effect of the micro-environment of fiber catalysts on the catalytic activities though of special importance is limited. In this work, a novel strategy for the synthesis of phosphoric acid-functionalized polyacrylonitrile fibers with a polarity tunable surface micro-environment by hydrophobic groups for one-pot C–C and C–N bond formation reactions is reported. The special hydrophobic surface micro-environment of the fiber catalysts is proven to promote the catalytic activities impressively in cyclocondensation of β-ketoesters with 2-aminobenzamides, the Knoevenagel condensation as well as the multi-component Biginelli reactions in green solvents. Both the surface synergy of the catalytic sites and hydrophobic auxiliary groups (benzyl or n-butyl) in the surface of fiber catalysts and interface acceleration in reaction medium play an important role in the highly efficient promotion of catalytic activity. Thereby a surface synergistic mechanism is proposed to explain the micro-environment effect. In addition, the fiber catalysts could be simply separated from the reaction system using tweezers and directly used in the next cycle without further treatment. Importantly, even after 10 reaction cycles in water or ethanol, there is no significant loss in their catalytic activity. The results indicate that the phosphoric acid functionalized fibers show green and sustainable potential for industrial production. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile fibers were functionalized with different amines to construct special tridimensional catalytic microenvironments at the surface. The polarity of the microenvironments at the surface of the fiber catalyst was tuned by changing the ratio of hydrophobic and hydrophilic amines. The catalytic performances of these microenvironments were examined for a cyanation reaction in water. Among these fiber catalysts with different microenvironments, the one modified with more hydrophobic benzylamine groups (PANBTF) shows much higher catalytic activity than that modified by hydrophilic ethanolamine groups. PANBTF can efficiently and rapidly catalyze the cyanation reaction of benzaldehyde and ethyl cyanoformate in water with a yield of 94 % at room temperature within 40 min. Moreover, a mechanism promoted by the hydrophobic microenvironment has been proposed to explain the high and specific catalytic activity of PANBTF. In addition, this fiber catalyst exhibited excellent recyclability and reusability (8 times) without further treatment, and it also performed well in flow-chemistry tests and scaled-up experiments, which indicated potential for the application of PANBTF in industrial production. [ABSTRACT FROM AUTHOR]

A novel solid acid catalyst (PANEAPF) is developed by immobilization of phosphoric acid on polyacrylonitrile fiber through covalent bonding. Various characterization techniques such as elemental analysis (EA), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), etc. are utilized to confirm the successful grafting and the stability of the fiber catalysts during application. PANEAPF shows high catalytic activity in the acetalization of aldehydes owing to the high utilization efficiency of its functionalized acid sites. In addition, the strong polarity micro-environment in the surface layers of PANEAPF make it highly suitable for catalytic application in both water and alcohol. Furthermore, the fiber catalyst can be applied to the acetalization of aldehydes in a continuous-flow process at room temperature, and shows excellent reactivity and superior recyclability (over 20 times). The many advantages of PANEAPF such as simple preparation, convenient regulation of acid amount, high durability, and eco-friendly process make it very attractive for fixed-bed reactors in the chemical industry. [ABSTRACT FROM AUTHOR]

Purpose: The 21st century work environment calls for team members to be more engaged in their work and exhibit more creativity in completing their job tasks. The purpose of this study was to examine whether team performance pressure and individual goal orientation would moderate the relationships between individual autonomy in teams and individual engagement and creativity. Design/Methodology/Approach: A sample consisting of 209 team members and 45 team managers from 45 work teams in 14 companies completed survey measures. To test our hypotheses, we used multilevel modeling with random intercepts and slopes because the individual-level data were nested within the team-level data. Findings: Hierarchical linear modeling showed that team-level performance pressure attenuated the positive relations between job autonomy and three dimensions of engagement. There were also 3-way interactions between job autonomy, psychological performance pressure, and learning goal orientation in predicting three dimensions of engagement and creativity. Implications: This study highlights the importance of exploring the moderating effect of team-level task characteristics and individual differences on the relationships between job autonomy and individual engagement and creativity. Organizations need to carefully consider both individual learning goals and performance pressure when empowering team members with job autonomy. Originality/Value: This is one of the first studies to explore the association between individual job autonomy in teams and individual outcomes in a contingency model. We first introduced team performance pressure as a moderator of job autonomy and examined the 3-way interaction effects of performance pressure, individual job autonomy, and learning goal orientation. [ABSTRACT FROM AUTHOR]

As a decorative material, magnesium oxychloride cement was used as a photocatalyst supporter to purify the pollutants indoors. Due to excellent adsorption properties of activated carbon (AC), the photocatalytic composties, TiO/AC, were prepared and introduced into the porous magnesium oxychloride cement (PMOC) substrate to composite a sort of photocatalytic cementitious material (PCM). The optimal composite processes were assessed by gas chromatograph, using toluene as the target. By comparing the perspective of toluene purification and thorough decomposition, it can be found that the optimal mass ratio for TiO/AC composites is 4/25, and the heat treatment to TiO/AC sample at 350 °C can play the optimal synergetic role of adsorbents in photocatalytic process. The synergistic effect of TiO, AC and magnesium oxychloride cement (MOC) was also evaluated by gas chromatograph. One-take molding process was adopted to introduce the TiO/AC into PMOC substrate, and its optimal mass fraction was 4 wt%, while the appropriate density of substrate was 0.35 g/cm3. Toluene degradation showed that the prepared PCM can degrade pollutants efficiently. The appropriate treatment process of TiO/AC, mass of TiO/AC, substrate density, and stable pore structure should be coordinated to maximize the adsorption-photodegradation performance. The combination of photocatalytic materials, adsorbents, and building materials provided a new idea for the application of photocatalysis. [ABSTRACT FROM AUTHOR]

A novel photocatalytic cement based material was prepared. The distribution of TiO on the surface of cement was characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD), which showed the relationship of photocatalysis and presence of TiO. TiO also had an impact on cement hydration, which was studied by thermal analysis. With 300 W UV illuminations, formaldehyde and benzene were degraded efficiently by the prepared photocatalytic cement based materials. 15wt% TiO/cement showed the highest degradation efficiency and capability. The results show that formaldehyde and benzene can be degraded within 4 and 9 hours, respectively. Besides, inorganic ions can induce TiO agglomeration. As a result, the presence of inorganic ions in cement is unfavorable for degradation. The photocatalytic cement based materials were fabricated and the degradation efficiency of formaldehyde was measured on building roof under sunlight illumination. Formaldehyde in glass chamber can be degraded thoroughly within 10 days. [ABSTRACT FROM AUTHOR]

NbO doped 0.8BaTiO-0.2(NaBi)(MgTi)O (0.8BT-0.2NBMT) polycrystalline ceramics were prepared by solid state reaction method. 0.8BT-0.2NBMT samples were observed to possess two dielectric peaks, which were attributed to the formation of core-shell structure (Huang et al. in J Eur Ceram Soc 36:533-540, 2015). Longer sintering induced uniform distributions of the additives. The introduction of NbO into 0.8BT-0.2NBMT could obviously bring about the improvement of the dielectric temperature stability, the degradation of the dielectric loss at room temperature and the decrease of the sintering temperature. The 0.8BT-0.2NBMT ceramics doped with 2.0 at% NbO could satisfy the temperature range of the X9R (−55 to 200 °C, △C/C = ±15% or less) characteristics, with a moderate dielectric constant of 1130, low dielectric loss of 0.7%, low sintering temperature of 1050 °C and insulation resistivity of 5 × 10 Ω cm at room temperature, which might be promising for practical use in multilayer ceramic capacitors. The inhomogeneous distribution and the existence of the secondary phases were responsible for this excellent dielectric temperature characteristic. The complex impedance analysis was introduced to elaborate the conduction mechanism. [ABSTRACT FROM AUTHOR]

To understand the mechanism of the photocatalytic direct synthesis of 1,1-diethoxyethane (DEE) from ethanol is vital for enhancing the reaction efficiency. Based on photocatalytic data of different phase TiO2 and F–TiO2 catalysts, radical trapping data, and GC-MS data, we proposed a photocatalytic mechanism for the preparation of both DEE in neat ethanol and 2,3-butanediol (2,3-BD) in ethanol–H2O using photocatalytic methods. In neat ethanol, hydroxyl isn’t involved in the catalytic cyclic process but hydroxyl has an indirect site-holding effect, thus leading to more hydroxyl groups with higher activity. In ethanol–H2O, although the strong oxidant ṖOH radical is involved, fewer OH groups lead to higher selectivity of 2,3-BD. The interaction of the reactant/solvent with the surface group of the catalyst is important in the activity and selectivity of photocatalytic reactions. This finding gives fundamental insight into the role of TiO2 surface hydroxyl in the photocatalytic dehydrogenation process of alcohols and opens a promising path to obtaining both high selectivity and high conversion in TiO2-based photocatalytic activity. [ABSTRACT FROM AUTHOR]

A thiadiazole-functionalized polyacrylonitrile fiber (DPTD-PANPF) qualitative colorimetric sensor was prepared for the first time, and its absorption properties were investigated in detail. The obtained sensor exhibits excellent chelating selectivity towards Ag+ without interference by other co-existing ions (Pb2+, Hg2+, Cd2+, Zn2+, and Cu2+) and generates a remarkable visual color change from yellow to red-brown over a wide pH range from 3 to 12. The DPTD-PANPF for Ag+ has a naked-eye detection limit of 11 ppb (only one in ten thousand of that of the small molecule DPTD) and a much higher saturation absorption capacity of 149 mg g−1. Moreover, the fiber can be repeatedly used more than 50 times. In summary, this fiber sensor possesses the advantages of excellent selectivity, lower detection limit, outstanding absorption capacity and reusability to detect and remove Ag+ from water. [ABSTRACT FROM AUTHOR]

A density functional plane-wave pseudopotential method is used to study the doping mechanisms of impurity defects(Bi, Y) in BaTiO-BiYO. Single Bi and Y impurities have little structure distortion. Bi forms ionic bond with nearby O atom in single Bi impurity, Y formed [YO] octahedral in single Y impurity. However, in the co-doped Bi and Y structure, Bi formed three valence bonds with nearby O atom, which causes the large structure distortion. The doped ion makes the mobile of Ti difficult and loss local ferroelectricity, which will broaden the dielectric constant temperature curve and increase the temperature stability of BaTiO ceramic matrix. [ABSTRACT FROM AUTHOR]

Three chiral pyrrolidine functionalized polyacrylonitrile fiber catalysts have been designed, prepared, and evaluated for their catalytic performance in asymmetric Michael addition of ketones to nitrostyrenes in water. With the optimized catalysts and conditions in hand, their reaction scope for nitrostyrenes was explored. Then the fiber catalysts were further applied to a packed-bed reactor for continuous-flow Michael addition. Based on the fact that organic solvent can inhibit the catalytic activity, a novel microenvironment catalytic mechanism is proposed. [ABSTRACT FROM AUTHOR]

A series of polyacrylonitrile fiber-supported quaternary ammonium salts (PANF-QAS) were prepared and applied to the catalytic reduction of aldehydes, ketones, azides, and benzyl halides in water using NaBH4 as the reducing reagent in a highly efficient, economic, and environmentally benign way. The structure–activity relationships were investigated, which showed that the catalysts made up of quaternary ammonium salts with longer alkyl chains, larger cationic radii and better lipophilicity speed up the reduction reaction to afford the products in excellent yield. Moreover, the optimized catalyst can be applied to the reduction of 1-naphthaldehyde in a continuous flow process with outstanding reactivity and recyclability. [ABSTRACT FROM AUTHOR]

A facet-dependent photo-deactivation mechanism of Cu2O was verified and reported, which is caused by the facet-dependent charge carrier transport. During irradiation, the {100} and {110} crystal facets are selectively corroded by the photo-generated holes, while the {111} facets are comparatively stable. [ABSTRACT FROM AUTHOR]

BaxSr1-xTiO3-(Ba-B-Al-Si-O) glass ceramics (BST-BBAS) with various amounts of CeO2added, were prepared via melt-quenching technique followed by controlled crystallization. X-ray diffraction reveals that the doping of CeO2restrains the impurity phase in the glassceramics. Besides, the dielectric breakdown strength increases to 1488kV/cm with 0.5 mol% CeO2content. Due to the combined effect of quite high breakdown strength and comparatively high dielectric constant, the energy storage density of 3.2 J/cm3was achieved in the glassceramics with 0.5 mol% CeO2, indicating that the CeO2added is an effective method to improve the energy storage density of BST-BBAS glass ceramics. [ABSTRACT FROM AUTHOR]