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• A new composite lattice structure with variable density and multi-configuration arrangement. • Lattice cells with different configurations are arranged in different regions. • The thin rods of cells were improved by cell replacement. • The composite arrangement further enhances the mechanical properties of lattice materials. A new composite lattice structure is proposed by combining variable density and multi-configuration arrangement. The parameter mapping model is established, and three composite lattice structure models are presented. The samples are prepared by the additive manufacturing technology SLS (Selective Laser Sintering) with Nylon PA6. The samples are tested by the universal testing machine and drop weight impact testing system. The load-deformation, equivalent impact load and failure mode are analyzed. The results show that compared with the variable density lattice structure, composite model 1 (GBCC cells in the low-density region are replaced by ECC cells) improves the thin rods in the low-density region, composite model 2 (the cell sizes in the high-density region are increased while GBCC cells in the low-density region are replaced by ECC cells) increases the equivalent bending stiffness by 8%, enhances the bending and impact deformation resistance of materials, and composite model 3 (GBCC cells in the high-density region are replaced by BCCxy cells) increases the failure load by 77%, reduces the equivalent impact load by 47%, and improves the toughness and cushioning performance of materials. This work finds that the composite lattice structure with variable density and multi-configuration further improves the mechanical property of lattice materials. [ABSTRACT FROM AUTHOR]

Moringa oleifera Lam. leaves (MOLLs) are recognised as new raw food material with various nutritional factors and phytochemical components. In recent years, a large number of studies have been conducted on deciphering the chemical composition and biological functions of MOLLs. However, the research data on MOLLs are scattered, and the future application trends are not summarised. In this review, we recapitulate the nutritional and phytochemical components of MOLLs, including their nutritional components, biological factors, and functional benefits, while emphasising the safety and application of MOLLs as a new raw food material. Currently, research has been focused on establishing MOLLs as novel raw food material. MOLLs constitute a variety of bioactive compounds, such as phenolic, flavonoids, protein, polysaccharides, vitamins, minerals. These bioactive compounds exhibit anti-inflammatory, anti-tumour, antibacterial, antioxidant, and anti-diabetic activities. As a promising and economic Chinese herbal medicine and functional food, MOLLs is widely used in the food and pharmaceutical industry. We mainly focus on summarising the findings about the nutritional components, chemical substances, and functional activities of MOLLs and discuss the practical applications of MOLLs as a new raw food material in the food and agriculture industries. Furthermore, this review provides an innovative approach for the application of MOLLs in the food industry and agriculture, discusses the current developments and problems of deep processing products of MOLLs, and provides insights into the future sustainable development options of MOLLs industries. [Display omitted] • The nutritional composition, functional factors, and biological activities of Moringa oleifera Lam. Leaves are summarised and discussed. • The multi-faceted applications of Moringa oleifera Lam. leaves in food and agriculture industries are summarised and compared. • The future trends and knowledge gaps of Moringa oleifera Lam. Leaves are proposed. [ABSTRACT FROM AUTHOR]

Three zinc(II) halide complexes ZnL2X2 (X=Cl, Br, I; L=4-methoxylbenzaldehyde thiosemicarbazone) have been synthesized and characterized by spectroscopic techniques. The complexes exhibit powder SHG efficiency approximately ten times higher than that of urea. The molecular hyperpolarizabilities are calculated to be −2.6×10−30 esu for the free ligand L, and −4.6×10−30, −6.2×10−30, −10.1×10−30 esu for the three zinc complexes, respectively. The former two complexes crystallize in the noncentrosymmetric space group Aba2, whilst ZnL2I2 crystallizes in the centrosymmetric space group P21/c and does not exhibit any SHG efficiency. The zinc(II) atom in these complexes is tetrahedrally coordinated by two neutral sulfur atoms from the corresponding thiosemicarbazones and two halide anions. The relationships between the molecular structures and nonlinear optical properties were studied based on theoretical calculation and experimental determination methods. [Copyright &y& Elsevier]

Structural vibration and noise radiation of a single-stage centrifugal compressor excited by the internal unsteady flow is investigated experimentally in the first part of our work [Zhou et al. Appl Acoust 2018;131:112–28]. Experimental results for acceleration of vibration and sound pressure under different rotational speeds indicate that the straight discharge pipe connecting the volute is forced to vibrate the most intensively at the blade passing frequency (BPF) and acts as the major contributor to the compressor noise emission. In this paper, a pipe micro-perforated panel (PMPP) is optimally designed with the genetic algorithm to suppress vibration and noise radiation of the straight discharge pipe section. A maximum sound pressure level (SPL) reduction of 20 dB for the BPF component and 8 dB for the overall noise are observed under the tested working conditions, while the influence of the PMPP on the aerodynamic performance of the compressor is negligible. The PMPP may be a promising method for controlling the tonal component of vibro-noises radiated from the centrifugal compressor. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the noise radiated from a centrifugal compressor unit, which mainly consists of a single-stage compressor connected with inlet and outlet pipes, a variable-frequency driving motor, a transmission gearbox and a bearing box. Sound pressure level spectra were measured at three rotational speeds each with several mass flow rates. The experimental results reveal that the overall sound pressure level increases with the rotational speed but varies slightly with the flow rate. The largest overall sound pressure level occurs at the measuring point near the motor, implying that the motor is one of the most important noise sources of the test rig. The frequencies of the tonal components are respectively consistent with the shaft frequency, the blade passing frequency of the compressor impeller and the interaction frequency of the magnetic flux wave with rotor slots in the variable-frequency motor. For sampling points near the connected pipes, the broadband noises mainly arise from the internal random pressure fluctuation through a curve fitting analysis of the squared sound pressure versus the dimensionless frequency. A coherence analysis between the acoustical and vibrational signals implies that the structural vibration induced by the internal pressure loads is the primary contributor for the compressor noise. Particularly, the outlet pipe with the highest vibration level should be a major concern for noise reduction of the centrifugal compressor. [ABSTRACT FROM AUTHOR]

Abstract: Natural antisense transcripts (NATs) exist ubiquitously as pivotal molecules to regulate coding gene expression. Sirtuin 1 (Sirt1) is a NAD-dependent deacetylase which is involved in myogenesis. However, whether Sirt1 transcribes NAT during C2C12 differentiation is still unknown. In this study, we identified a Sirt1 NAT which was designated as Sirt1 antisense long non-coding RNA (AS lncRNA) by sequencing and bioinformatic analysis. The level of Sirt1 AS lncRNA was greater in spleen but less in muscle tissue. The expression of both Sirt1 mRNA and Sirt1 AS lncRNA decreased during C2C12 myogenic differentiation, whereas the levels of miR-34a, which targets Sirt1, increased gradually. We further found that the half-life of Sirt1 AS lncRNA was 10h, but that of Sirt1 mRNA was 6h in C2C12 cells treated with 2μg/ml Actinomycin D. Therefore, compared with Sirt1 mRNA, Sirt1 AS lncRNA was more stable. Overexpression of Sirt1 AS lncRNA increased the levels of Sirt1 protein, whereas overexpression of Sirt1 AS lncRNA mutant did not affect the level of Sirt1 protein in C2C12 cells. Moreover, downregulation of Sirt1 mRNA caused by miR-34a was counteracted by Sirt1 AS lncRNA in C2C12 cells. Taken together, we identified a novel NAT of Sirt1 which implicated in myogenesis through regulating Sirt1 expression. [Copyright &y& Elsevier]

Abstract: The mechanisms for the abstraction reactions of germylenes with oxirane and thiirane have been characterized in detail using density functional theory. All the stationary points were determined at the B3LYP/6-311++G (d, p) level of the theory. As a result, our theoretical investigations suggest that, irrespective of deoxygenation and desulfurization, the alkyl-substituted germylene abstractions are much more favorable than those of the π-donor-substituted germylenes. Moreover, for a given germylene, the desulfurization reaction is more exothermic as well as more kinetically favorable. Furthermore, a configuration mixing model based on the work of Pross and Shaik is used to rationalize the computational results. A comparison with carbene and silylene also led to the same result and the results obtained allowed a number of predictions to be made. [Copyright &y& Elsevier]

Abstract: The mechanisms for the insertion reactions of alkylidenecarbenes with CH3O–H have been investigated at the B3LYP/6-311G(d,p) level of the theory. According to our model calculations these insertion reactions will easily yield vinyl ether products and for a given single substituted alkylidenecarbene will yield cis–trans-isomer mixture. Moreover the reactivity of alkylidenecarbene decreases in the order: HFCsp="0.25" />>HClCsp="0.25" />>HBrCsp="0.25" />>H(CH3)Csp="0.25" />>H2Crmore, a configuration mixing model based on the work of Pross and Shaik is used to rationalize the computational results. [Copyright &y& Elsevier]