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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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

The barium strontium titanate (BaSrTiO) glass-ceramics doped with different content of La were prepared via controlled crystallization. Phase compositions, microstructure and dielectric behaviors were investigated systematically. The results revealed that LaO additives had little influence on the dielectric constant but significantly changed the microstructure of the glass-ceramics, which led to improved breakdown strength (BDS). The optimized energy-storage density of 3.18 J/cm was achieved in the glass-ceramics with 1.0 wt% LaO content which is 2.56 times higher than pure BST glass-ceramics, suggesting glass-ceramics of this composition could be an attractive candidate for energy-storage applications. [ABSTRACT FROM AUTHOR]

CaCuTiO (CCTO) ceramics doped with Zr were prepared. Effects of Zr on microstructure, dielectric properties and conduction behavior of CaCuTiZrO ( x=0, 0.05, 0.10, 0.20) ceramics were studied in the frequency range of 10-10 Hz. Grain size and dielectric loss of Zr-doped CCTO ceramic decreased compared with pure CCTO. The loss tangent (tan δ) of CaCuTiZrO ( x=0.20) ceramic droped to 0.05 at a frequency of 1 kHz, which was reduced by 55% compared with pure CCTO ceramic. The mechanism effect of electrical conductivity on dielectric loss of Zr-doping CCTO ceramics was also discussed. [ABSTRACT FROM AUTHOR]

Efficient and selective preparation of amides from arylamines and esters has been achieved with an AlCl/EtN pair under mild conditions. A large number of arylamines were successfully acylated to the corresponding amides in high yields and short reaction times. For instance, a 94% yield of p-bromoacetanilide was obtained from p-bromoaniline and ethyl acetate in 10 min at room temperature. In addition, a computational study on the N-acylation of amines was performed using density functional theory. It was found that the energy barrier for N-acylation of aniline is 10 kcal/mol higher than that of methylamine. In the presence of AlCl, the activation energy for the N-acylation of aniline was reduced by 27.7 kcal/mol with the endothermic process becoming exothermic. Graphical Abstract: In this work, the efficient and selective preparation of amides from arylamines and esters has been performed successfully with an AlCl/EtN pair under mild conditions. A large number of arylamines were acylated to the corresponding amides with high yields and short reaction times. In addition, a computational study on the N-acylation of amines has been carried out using the density functional theory (DFT) method.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]