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Abstract: Optimizing feed efficiency through the feed conversion ratio (FCR) is paramount for economic viability and sustainability. In this study, we integrated RNA-seq, ATAC-seq, and genome-wide association study (GWAS) data to investigate key functional variants associated with feed efficiency in pigs. Identification of differentially expressed genes in the duodenal and muscle tissues of low- and high-FCR pigs revealed that pathways related to digestion of dietary carbohydrate are responsible for differences in feed efficiency between individuals. Differential open chromatin regions identified by ATAC-seq were linked to genes involved in glycolytic and fatty acid processes. GWAS identified 211 significant single-nucleotide polymorphisms associated with feed efficiency traits, with candidate genes PPP1R14C, TH, and CTSD. Integration of duodenal ATAC-seq data and GWAS data identified six key functional variants, particularly in the 1500985–1509676 region on chromosome 2. In those regions, CTSD was found to be highly expressed in the duodenal tissues of pigs with a high feed conversion ratio, suggesting its role as a potential target gene. Overall, the integration of multi-omics data provided insights into the genetic basis of feed efficiency, offering valuable information for breeding more efficient pig breeds. [ABSTRACT FROM AUTHOR]

The DC side fault of the high voltage DC transmission system based on modular multilevel converters high voltage DC (MMC-HVDC) is easily affected by the double influence of AC transient electrical quantity infeed and overvoltage and overcurrent, seriously threatening the safe operation of the power grid. Aiming at the problem above, a fault suppression strategy in dual mode of isolation and current limiting is proposed. Based on the half-bridge-full-bridge hybrid MMC, the fault transient mathematical model considering AC feed and sub-module switching feed is analyzed. AC isolation module with double conduction self-resistance structure and current-limiting control module is constructed, which can be adaptively adjusted to the system's direct current parameters. The ±500 kV double-ended hybrid MMC system model is established to verify the scheme's effectiveness. In addition, the influence of high AC modulation parameters on the suppression effect is investigated. PSCAD/EMTDC simulation results show that AC active and reactive power feed-in peaks are reduced by 388.69 MW and 119.82 Mvar, respectively, under dual-mode control. The peak value of DC overvoltage and overcurrent is reduced by 1211.53 kV and 22.5 kA, respectively, the fault self-clearing time is shortened by 43 ms, and the fault suppression effect is remarkable. In the high AC modulation ratio operating state, the modulation parameters are positively correlated with the AC power feed and negatively correlated with the overvoltage and overcurrent of the DC system. The research results provide support for the fault protection scheme of the hybrid MMC flexible and direct power grid. [ABSTRACT FROM AUTHOR]

The aqueous ethanol extract of Periplaneta americana (PAE) dramatically stimulates wound healing by promoting the migration of keratinocytes. The aims of this study were to identify the active oligopeptides present in PAE that promote wound healing and to elucidate their underlying molecular mechanisms. For the detection of cell migration and proliferation in vitro, Transwell assays, wound healing assays, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were performed on the human keratinocyte cell line HaCaT. Western blot analysis was performed on the HaCaT cells to detect the protein levels of SMAD family member 3 (Smad3) and phosphorylated Smad3 (P-Smad3). Immunofluorescence analysis was performed on the HaCaT cells to detect the degree of Smad3 translocation into the nucleus. Three oligopeptides were purified from PAE via a series of chromatographic techniques, and their individual effects on HaCaT cell migration were evaluated using wound healing assays. The purification techniques employed were gel filtration chromatography, C8 reversed-phase column chromatography, and reversed-phase high-performance liquid chromatography (RP-HPLC). The amino acid sequences of the oligopeptides (LAKF, PYAHF, and PQLSY) were identified via HPLC–tandem mass spectrometry (HPLC–MS/MS) and Edman degradation. The oligopeptide with the PYAHF sequence significantly promoted HaCaT cell migration. In addition, this oligopeptide promoted the nuclear translocation of P-Smad3 by activating the Smad3 signaling pathway. The findings of this study provide a foundation for the future development of peptide drugs for promoting wound healing. [ABSTRACT FROM AUTHOR]

Light-matter interactions in low-dimensional quantum-confined structures can dominate the optical properties of the materials and lead to optoelectronic applications. In anisotropic layered silicon diphosphide (SiP2) crystal, the embedded quasi-one-dimensional (1D) phosphorus-phosphorus (P—P) chains directly result in an unconventional quasi-1D excitonic state, and a special phonon mode vibrating along the P—P chains, establishing a unique 1D quantum-confined system. Alloying SiP2 with the homologous element serves as an effective way to study the properties of these excitons and phonons associated with the quasi-1D P—P chains, as well as the strong interaction between these quasiparticles. However, the experimental observation and the related optical spectral understanding of SiP2 with isoelectronic dopants remain elusive. Herein, with the photoluminescence and Raman spectroscopy measurements, we demonstrate the redshift of the confined excitonic peak and the stiffening of the phonon vibration mode B1g3 of a series of Si(P1−xAsx)2 alloys with increasing arsenic (As) compositions. This anomalous stiffening of is attributed to the selective substitution of As atoms for P atoms within the P—P chains, which is confirmed via our scanning transmission electron microscopy investigation. Such optical spectra evolutions with selective substitution pave a new way to understand the 1D quantum confinement in semiconductors, offering opportunities to explore quasi-1D characteristics in SiP2 and the resulting photonic device application. [ABSTRACT FROM AUTHOR]

In order to improve the thermoelectric and mechanical properties of p-type Bi2Te3 thermoelectric material, Bi0.5Sb1.5Te3/Ni&Cu core/shell powders were electroless plated with the same content of Ni and different content of Cu, and then reduced by hydrogen, and finally sintered into bulk by spark plasma sintering. After composite electroless plating with Ni&Cu, for the bulk sample with 0.3 wt% Ni and 0.15 wt% Cu, the power factor rises significantly and the highest value increases from 25 to 33 µW·cm−1·K−2 at room temperature. Meanwhile, the thermal conductivity decreases to about 0.80 W·m−1·K−1 at 623 K. Therefore, the composite electroless plating with Ni&Cu can obviously improve the electrical and thermal transport performance of p-type Bi2Te3 based thermoelectric materials. Thus, the ZT value enhances significantly and the highest value increases over 3 times, from 0.35 to 1.16 at 473 K in Bi0.5Sb1.5Te3 with 0.3 wt% Ni and 0.15 wt% Cu bulk sample. At the same time, the mechanical properties have also been improved after composite electroless plating with Ni&Cu. [ABSTRACT FROM AUTHOR]

SF6, which is currently widely used in gas-insulated power transmission equipment, is a greenhouse gas with a very strong greenhouse effect. Therefore, developing environmentally friendly gas insulation equipment to gradually reduce the use of SF6 has become a hot research topic. As the most potential alternative gas, C4F7N is of great significance to study the electrical characteristics of the medium-voltage switching field to promote the green development of the power industry. Based on multi-physical field coupling to construct the 40.5 kV circuit breaker mode, this paper uses C4F7N/CO2 mixed gas to compare and study the dynamic characteristics of a C4F7N/CO2 mixed gas circuit breaker when breaking the short-circuit current and the dielectric recovery strength with no-load breaking, as well as to evaluate the electrical performance of C4F7N mixed gas in a 40.5 kV breaker with the gas breakdown criterion. The results show that mixing O2 in a high current can improve the breaking performance of an environmental protection circuit breaker and increasing the C4F7N mass fraction can enhance the dielectric recovery strength of the environmentally friendly circuit breaker. Considering the overall performance of the gas, the 5%C4F7N/90% CO2/5%O2 mixed gas has some alternative potential. [ABSTRACT FROM AUTHOR]

Strain engineering can serve as a powerful technique for modulating the exotic properties arising from the atomic structure of materials. Examples have been demonstrated that one-dimensional (1D) structure can serve as a great platform for modulating electronic band structure and phonon dispersion via strain control. Particularly, in a van der Waals material silicon diphosphide (SiP2), quasi-1D zigzag phosphorus–phosphorus (P-P) chains are embedded inside the crystal structure, and can show unique phonon vibration modes and realize quasi-1D excitons. Manipulating those optical properties by the atom displacements via strain engineering is of great interest in understanding underlying mechanism of such P-P chains, however, which remains elusive. Herein, we demonstrate the strain engineering of Raman and photoluminescence (PL) spectra in quasi-1D P-P chains and resulting in anisotropic manipulation in SiP2. We find that the phonon frequencies of SiP2 in Raman spectra linearly evolve with a uniaxial strain along/perpendicular to the quasi-1D P-P chain directions. Interestingly, by applying tensile strain along the P-P chains, the band gap energy of strained SiP2 can significantly decrease with a tunable value of ∼ 55 meV. Based on arsenic (As) element doping into SiP2, the strain-induced redshifts of phonon frequencies decrease, indicating the stiffening of the phonon vibration with the increased arsenic doping level. Such results provide an opportunity for strain engineering of the light–matter interactions in the quasi-1D P-P chains of SiP2 crystal for potential optical applications. [ABSTRACT FROM AUTHOR]

Bi2Te2.7Se0.3/Cu core/shell powders were prepared by electroless plating and hydrogen reduction, and then sintered into bulk by spark plasma sintering in order to improve the thermoelectric and mechanical properties of n-type Bi-Te thermoelectric material. After electroless plating, with the increasing of Cu content, Seebeck coefficient keeps increasing and power factor enhances significantly. The highest power factor increases by three times and reaches 23.8 W·cm−1·K−2 at room temperature in Bi2Te 2.7Se0.3 with 0.22wt% Cu sample, which means electrical transport properties of Bi2Te2.7Se0.3/Cu samples have been improved. Meanwhile, the ZT values of Bi2Te2.7Se0.3/Cu samples can be enhanced at different temperature zone by adjusting the Cu content. Bi2Te2.7Se0.3 with 0.05wt% Cu sample has the best thermoelectric properties in high temperature zone, and the ZT peak value increases from 0.35 to 0.85 at 623 K. When the Cu content increases to 0.15wt%, the ZT peak value moves to the low temperature (373 K) and increases from 0.24 to 0.71. At the same time, the mechanical properties increases with the increasing of Cu content. [ABSTRACT FROM AUTHOR]

Bi0.5Sb1.5Te3/Cu core/shell powders were prepared by electroless plating and hydrogen reduction, and then sintered into bulk by spark plasma sintering. After electroless plating, with increasing the Cu content, the electrical conductivity keeps enhancing significantly. The highest electrical conductivity reaches 3341S/cm at room temperature in Bi0.5Sb1.5Te3 with 0.67wt% Cu bulk sample. Moreover, the lowest lattice thermal conductivity reaches 0.32 W/m·K at 572.2 K in Bi0.5Sb1.5Te3 with 0.67wt% Cu bulk sample, which is caused by the scattering of the rich-copper particles with different dimensions and massive grain boundaries. According to the results, the ZT values of all Bi0.5Sb1.5Te3/Cu bulk samples have improved in a high temperature range. In Bi0.5Sb1.5Te3 with 0.15wt% Cu bulk sample, the highest ZT value at 573.4 K is 0.81. When the Cu content increases to 0.67wt%, the highest ZT value reaches 0.85 at 622.2 K. Meanwhile, the microhardness increases with increasing the Cu content. [ABSTRACT FROM AUTHOR]

The present paper employs a synergetic approach to exploring the relationship between the length and frequency among English multiword formulaic sequences. It attempts to test whether Zipf's assumption on the inverse relationship between word length and word frequency, as well as the synergetic model constructed at lexical level, can be extended to multiword formulaic sequences. A corpus-driven approach is adopted to acquire sufficient data. Results show partial applicability of the assumption to a small part of formulaic sequences: sequences of words with whole structure and complete meaning. However, the majority of formulaic sequences, lexical bundles, are proved to be an exception to the conventional rule. The paper tries to offer explanation by exploring further the features of lexical bundles. It concludes that the synergetic system of length and frequency among lexical bundles is operated under the compromise between the requirements of minimization of production efforts and the requirements of maximization of information. Based on the analysis of synergetic relationship between length and frequency, this research shall prove that language is a self-regulating system, and that observed language phenomena can be understood and explained by laws and models. Besides, this study also includes register differences and offers a new perspective to register analysis. [ABSTRACT FROM AUTHOR]

Copper coated Bi 0.5 Sb 1.5 Te 3 powders were prepared through electroless plating with simplified pretreatment method. After hydrogen reduction, the powders are consolidated into bulk by spark plasma sintering. The lowest lattice thermal conductivity in Bi 0.5 Sb 1.5 Te 3 /Cu reduces to 0.25 W/m·K at 371.5 K after annealing. The figure of merit ( ZT ) of Bi 0.5 Sb 1.5 Te 3 /Cu ascends in a large scale and reaches 1.08 at 373 K and 423 K before and after annealing respectively. The average ZT values of Bi 0.5 Sb 1.5 Te 3 /Cu samples both rise from 0.36 to 0.82, which makes this material suitable for application in a wide temperature range. [ABSTRACT FROM AUTHOR]

Interlayer coupling in two-dimensional (2D) layered materials plays an important role in controlling their properties. 2H- and 3R-MoS 2 with different stacking orders and the resulting interlayer coupling have been recently discovered to have different band structures and a contrast behavior in valley physics. However, the role of carrier doping in interlayer coupling in 2D materials remains elusive. Here, based on the electric double layer interface, we demonstrated the experimental observation of carrier doping-enhanced interlayer coupling in 3R-MoS 2 . A remarkable tuning of interlayer Raman modes can be observed by changing the stacking sequence and carrier doping near their monolayer limit. The modulated interlayer vibration modes originated from the interlayer coupling show a doping-induced blue shift and are supposed to be associated with the interlayer coupling enhancement, which is further verified using our first-principles calculations. Such an electrical control of interlayer coupling of layered materials in an electrical gating geometry provides a new degree of freedom to modify the physical properties in 2D materials.