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Salmonella typhi is a pathogen that causes the human disease of typhoid fever. The aim of this study was to investigate the viable but nonculturable (VBNC) state of S. typhi. Some samples were stimulated at 4°C or -20°C, while others were induced by different concentrations of CuSO4. Total cell counts remained constant throughout several days by acridine orange direct counting; however, plate counts declined to undetectable levels within 48 hours by plate counting at -20°C. The direct viable counts remained fairly constant at this level by direct viable counting. Carbon and nitrogen materials slowly decreased which indicated that a large population of cells existed in the VBNC state and entered the VBNC state in response to exposure to 0.01 or 0.015¿mmol/L CuSO4 for more than 14 or 12 days, respectively. Adding 3% Tween 20 or 1% catalase enabled cells to become culturable again, with resuscitation times of 48¿h and 24¿h, respectively. The atomic force microscope results showed that cells gradually changed in shape from short rods to coccoids, and decreased in size when they entered the VBNC state. Further animal experiments suggested that resuscitated cells might regain pathogenicity. [ABSTRACT FROM AUTHOR]

Without regarding interlayer continuity of transverse shear stresses in the displacement expressions, traditional higher-order plate theories have difficulty in predicting continuous shear stress fields accurately for multilayered functionally graded carbon nanotube-reinforced composite (FG-CNTRC) plates with independent CNT distributions in each layer. In this paper, a new higher-order continuous shear stress multilayered plate model is developed for high-accuracy analysis of FG-CNTRC plates. In the theoretical formulation, higher-order interpolation functions and piecewise descriptions are adopted for transverse shear stress fields. By fulfilling the interlayer continuity of shear stresses and displacements, the displacement expressions for FG-CNTRC plates are formulated. The accuracy of the proposed model is determined by two kinds of parameters: the order of assumed transverse shear stress fields and the number of subdivisions. Compared with traditional higher-order theories, the proposed model can accurately predict continuous transverse shear stresses for FG-CNTRC plates with different CNT configurations by constitutive relations directly. Additionally, a four-node rectangular plate element associated with the proposed model is formulated. Results show that the proposed model agrees well with the exact solutions and results from ANSYS. With the same amount of calculation, the proposed higher-order model has higher accuracy than the model with more subdivisions, especially for asymmetric plates with discontinuous CNT ply angle. [ABSTRACT FROM AUTHOR]

The excessive use of antibiotics and chemical preservatives has led to the emergence of resistant bacterial strains, which has had an adverse impact on food safety. The utilization of antimicrobial peptides (AMPs) in food preservation has garnered attention due to their ability to maintain the quality of food while reducing the likelihood of bacteria developing resistance. Mytimacin-4, an antimicrobial peptide rich in cysteine and positively charged, has been identified in Mytilus galloprovincialis and has been reported to possess antibacterial activity. However, the specific effect of mytimacin-4 on bacteria is still not well understood. Hence, this study aimed to prepare mytimacin-4 using a Pichia pastoris expression system and to investigate its antibacterial properties and mechanism. Our findings indicate that mytimacin-4 exhibits rapid and sustained bactericidal effects against bacteria and no cytotoxicity or hemolytic activity. Additionally, microscopy techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and fluorescence microscopy have demonstrated that mytimacin-4 disrupts the integrity of bacterial membranes, damages intracellular structures, and binds to bacterial DNA. Furthermore, mytimacin-4 had a great antimicrobial effect against the dominant bacteria of pork, improving the abundance and variety of bacterial flora during refrigeration and controlling the rise in pH, total volatile basic nitrogen (TVBN), and thiobarbituric acid reactive substances (TBARS) in pork, preserving the freshness of pork during storage at 4 °C. Moreover, mytimacin-4 demonstrated significant antibacterial effects against three types of bacteria in a pork spoilage model. Overall, mytimacin-4 holds great potential as a food preservative for storage purposes. • The mytimacin-4 exhibited a broad antimicrobial spectrum. • The mytimacin-4 showed no cytotoxicity and hemolytic activity. • The mytimacin-4 damaged intracellular structures, and bound to bacterial DNA. • The mytimacin-4 improved the microbial diversity of pork during refrigeration. • The mytimacin-4 preserved the freshness of pork during the storage period at 4 °C. [ABSTRACT FROM AUTHOR]

New vinegar needs a long maturing time to improve its poor flavor before sale, which greatly increases its production cost. Therefore, it is urgent to explore regulation technologies to accelerate vinegar flavor maturation. Based on literature and our research, this review introduces the latest advances in flavor regulation technologies of vinegar including microbial fortification/multi starters fermentation, key production processes optimization and novel physical processing technologies. Microbial fortification or multi starters fermentation accelerates vinegar flavor maturation via enhancing total acids, esters and aroma precursors content in vinegar. Adjusting raw materials composition, fermentation temperature, and oxygen flow reasonably increase alcohols, organic acids, polyphenols and esters levels via generating more corresponding precursors in vinegar, thereby improving its flavor. Furthermore, novel processing technologies greatly promote conversion of alcohols into acids and esters in vinegar, shortening flavor maturation time for over six months. Meanwhile, the corresponding mechanisms are discussed and future research directions are addressed. Technologies and mechanisms to regulate vinegar flavor. [Display omitted] • Biofortification hastens vinegar flavor maturation via enriching flavor compounds. • Optimizing production process improves vinegar flavor by adding precursor substances. • New processing technologies shorten vinegar aging via fastening odorants formation. • Microbe and sonication are the most potential methods to regulate vinegar flavor. [ABSTRACT FROM AUTHOR]

Soy sauce is a traditional condiment that undergoes microbial fermentation of various ingredients to achieve its desired color, scent, and flavor. Sporidiobolus pararoseus , which is a type of Rhodocerevisiae , shows promising potential as a source of lipids, carotenoids, and enzymes that can enrich the taste and color of soy sauce. However, there is currently a lack of systematic and comprehensive studies on the functions and mechanisms of action of S. pararoseus during soy sauce fermentation. In this review, it is well established that S. pararoseus produces lipids that are abundant in unsaturated fatty acids, particularly oleic acid, as well as various carotenoids, such as β-carotene, torulene, and torularhodin. These pigments are synthesized through the mevalonic acid pathway and possess remarkable antioxidant properties, acting as natural colorants. The synthesis of carotenoids is stimulated by high salt concentrations, which induces oxidative stress caused by NaCl. This stress further activates crucial enzymes involved in carotenoid production, ultimately leading to pigment formation. Moreover, S. pararoseus can produce high-quality enzymes that aid in the efficient utilization of soy sauce substrates during fermentation. Furthermore, this review focused on the impact of S. pararoseus on the color and quality of soy sauce and comprehensively analyzed its characteristics and ingredients. Thus, this review serves as a basis for screening high-quality oleaginous red yeast strains and improving the quality of industrial soy sauce production through the wide application of S. pararoseus. • The synthesis pathway of lipids and carotenoids in S. pararoseus was illustrated. • S. pararoseus can compensate for lipid insufficiency during fermentation. • S. pararoseus can produce carotenoids under various environmental stresses. [ABSTRACT FROM AUTHOR]

Optimization based on traditional forward motion analysis to ensure a prescribed load distribution on a deformed geometry is challenging, since the load distribution is highly coupled to the deformed geometry, boundary conditions, and the optimized material layout. In contrast to traditional forward motion analysis, the deformed configuration is prescribed in the inverse motion analysis, and the undeformed configuration is the outcome of the analysis. Consequently, the inverse motion analysis is able to define an exact deformed geometry. In the present study, we make use of this key advantage to design structures with both an exact deformed geometry and a prescribed load distribution. The objective in the optimization is to minimize a general function of the nodal displacement vector. To formulate a well-posed optimization problem, the design is regularized using the partial differential equation filter and the sensitivity analysis is based on the adjoint method. The computational model is developed for neo-Hookean hyper-elasticity and the balance equations are discretized using the finite element method. The resulting nonlinear equations are solved using a conventional Newton–Raphson scheme. In the numerical examples, a cantilever beam with an embedded perfect circular shape is first considered. Next, a 2D gasket-like structure is designed, and finally, we consider a 3D structure with contact-like boundary conditions. In these examples, the prescribed deformed geometry is subject to a distributed external force. The examples show that the deformed geometry and load distribution can be exactly prescribed through stiffness optimization based on the inverse motion analysis. [ABSTRACT FROM AUTHOR]

Zhuhoujiang is a popular fermented soybean paste in China. The aroma profiles of Zhuhoujiang were systemically analyzed by gas chromatography–olfactometry/mass spectrometry (GC-O/MS). A total of 100 aroma compounds were detected, and 24 compounds were identified as the important aroma compounds by odor intensities and odor-activity values (OAV) analysis. Ethyl isovalerate, ethyl isobutyrate, linolenic acid, and eucalyptol were demonstrated to be the key aroma compounds of Zhuhoujiang by omission tests. Ethyl acetate, myrcene, and eucalyptol were strongly correlated to the cooling aroma characteristic of Zhuhoujiang, whereas ethyl isovalerate, ethyl isobutyrate, ethyl 4-methylvalerate, ethyl 2-methylbutyrate, linolenic acid, and d -limonene contributed most to the sweetness and aromatic flavor. Furthermore, full two-dimensional gas chromatography-mass spectrometry (GC × GC-TQMS) was applied and another 118 aroma compounds were identified including 48 esters. [Display omitted] • A total of 100 aromas were detected by GC-MS in Zhuhoujiang. • Another 118 aromas were identified including 48 esters by GC × GC-TQMS. • Ethyl esters accounted for over 50% important aroma compounds in Zhuhoujiang. • Ethyl acetate, myrcene, and eucalyptol were correlated to the cooling aroma. • Ethyl isovalerate, ethyl isobutyrate and linolenic acid were related to sweetness and aromatic flavor. [ABSTRACT FROM AUTHOR]

This paper presents a new sensitivity analysis method for coupled acoustic–structural systems subjected to non-stationary random excitations. The integral of the response power spectrum density (PSD) of the coupled system is taken as the objective function. The thickness of each structural element is used as a design variable. A time-domain algorithm integrating the pseudo excitation method (PEM), direct differentiation method (DDM) and high precision direct (HPD) integration method is proposed for the sensitivity analysis of the objective function with respect to design variables. Firstly, the PEM is adopted to transform the sensitivity analysis under non-stationary random excitations into the sensitivity analysis under pseudo transient excitations. Then, the sensitivity analysis equation of the coupled system under pseudo transient excitations is derived based on the DDM. Moreover, the HPD integration method is used to efficiently solve the sensitivity analysis equation under pseudo transient excitations in a reduced-order modal space. Numerical examples are presented to demonstrate the validity of the proposed method. [ABSTRACT FROM AUTHOR]

The non-stationary random response analysis of coupled acoustic-structural systems under non-stationary random excitations is investigated in this paper. By combining the pseudo excitation method (PEM) and high precision direct (HPD) integration method, an efficient method for the non-stationary random response analysis is proposed. PEM is used to derive the dynamic equation of coupled acoustic-structural systems under non-stationary random excitations and transform the non-stationary random response analysis to the deterministic pseudo transient response analysis. HPD method is used to further improve computational efficiency while maintaining high accuracy. Numerical examples are given to illustrate the validity of the developed approach. [ABSTRACT FROM AUTHOR]

Ultralight lattice structures exhibit excellent mechanical performance and have been used widely. In structural design, the fundamental frequency is highly important. Therefore, a multiscale topology optimization method was utilized to optimize the fundamental frequency of multimaterial lattice structures in this study. Two types of optimization problems were studied, namely, maximizing the natural fundamental frequency with mass constraints and minimizing compliance with frequency constraints. The Heaviside-penalty-based discrete material optimization method was adopted for the optimal selection of candidate materials. The asymptotic homogenization method was used to evaluate the equivalent macroscale properties according to the microstructure of the lattice material. To enable gradient optimization, sensitivities were outlined in detail. A density filter with a volume-preserving Heaviside projection was used to eliminate the risk of a checkerboard pattern and reduce the number of gray elements. A polynomial penalization scheme was employed to eliminate localized spurious eigenmodes in the low-density region. Finally, several numerical examples were performed to validate the proposed method. These numerical examples resulted in novel microstructural configurations with remarkably improved vibration resistance. [ABSTRACT FROM AUTHOR]

• Umami peptides were screened based on molecular docking and Machine learning. • Thirteen umami peptides were identified from yeast extract. • The umami intensity of DWTDDVEAR is the best than others. • Arg316, Ser401, and Asp315 are essential amino acids in the T1R1 binding domain. Yeast extract was separated by using ultrafiltration, gel filtration chromatography, and preparative high-performance liquid chromatography for analyzing the umami mechanism. 13 kinds of umami peptides were screened out from 73 kinds of peptides which were identified in yeast extract using nanoscale ultra-performance liquid chromatography-tandem mass spectrometry and virtual screening. The umami peptides were found to have a threshold range of 0.07–0.61 mM. DWTDDVEAR exhibited a strong umami taste with a pronounced enhancement effect for monosodium glutamate. Molecular docking studies revealed that specific amino acid residues in the T1R1 subunit, including Arg316, Ser401, and Asp315, played a critical role in the umami perception with these peptides. Overall, the study highlights the potential of natural flavor enhancers and provides insights into the mechanism of umami taste perception. [ABSTRACT FROM AUTHOR]

It is well known that the classical particle swarm optimization (PSO) is time-consuming when used to solve complex fitness optimization problems. In this study, we perform in-depth research on fitness estimation based on the distance between particles and affinity propagation clustering. In addition, support vector regression is employed as a surrogate model for estimating fitness values instead of using the objective function. The particle swarm optimization algorithm based on affinity propagation clustering, the efficient particle swarm optimization algorithm, and the particle swarm optimization algorithm based on support vector regression machine are then proposed. The experimental results show that the new algorithms significantly reduce the computational counts of the objective function. Compared with the classical PSO, the optimization results exhibit no loss of accuracy or stability. [ABSTRACT FROM AUTHOR]

• Yeast extract amino acids can shape the fermentation microbiota of soy sauce. • Yeast extract amino acids boost the competitiveness of aroma-producing microbiota. • The best mass ratio of neutral: acidic: basic amino acids is 58:27:15. • The best amino acid formula can increase the malt aroma of soy sauce by 52.6%. Yeast extracts, of which amino acids are the main component, can be directly applied to improve the flavor of final soy sauce. In this study, the potential of commercial yeast extracts was explored from amino acid approach to enhance the flavor quality of soy sauce by shaping the core fermentation microbiota. Alkaline and neutral amino acids favored the competitive benefits of flavor-producing bacteria, while acidic amino acids promoted the stress resistance of the fermentation microbiota, especially the abundance of Lactobacillus , which increased to 18.03–23.78% and became the predominant microbiota. The mass ratio of neutral-nonpolar: neutral-polar: acidic: alkaline amino acids was 40: 18: 27: 15, which provided the optimal improvement of soy sauce aroma. The formulation and activated the metabolic pathways of 3-methyl-1-butyraldehyde, 3-methyl-1-butanol and 2-methyl-1-propanol through Leu and Ile, resulting in a 52.6% increase in malt-like aroma. This study provides a new idea for the regulation of soy sauce fermentation. [ABSTRACT FROM AUTHOR]

The novel cesium chloride–lactose complex (CsCl·C 12 H 22 O 10 (Cs-Lac), cesium chloride- d -arabinose and l -arabinose complexes (CsCl·C 5 H 10 O 5 , Cs-D-Ara and Cs-L-Ara) have been synthesized and characterized using X-ray diffraction, FTIR, FIR, THz and Raman spectroscopies. Cs + is 9-coordinated to two chloride ions and seven hydroxyl groups from five lactose molecules in Cs-Lac. In the structures of CsCl- d -arabinose and CsCl- l -arabinose complexes, two kinds of Cs + ions coexist in the structures. Cs1 is 10-coordinated with two chloride ions and eight hydroxyl groups from five arabinose molecule; Cs2 is 9-coordinated to three chloride ions and six hydroxyl groups from five arabinose molecules. Two coordination modes of arabinose coexist in the structures. α- d -arabinopyranose and α- l -arabinopyranose appear in the structures of Cs-D-Ara and Cs-L-Ara complexes. FTIR and Raman results indicate variations of hydrogen bonds and the conformation of the ligands after complexation. FIR and THz spectra also confirm the formation of Cs-complexes. Crystal structure, FTIR, FIR, THz and Raman spectra provide detailed information on the structure and coordination of hydroxyl groups to metal ions in the cesium chloride–lactose, cesium chloride-D- and l -arabinose complexes. [ABSTRACT FROM AUTHOR]

Knowledge of weathered depth is critically important for repairing and protecting stone relics that are open to elements. Weathered depth is an important basis of stability/durability evaluation and protection plan formulation for stone carving and grottoes. Weathered depth is the basis for identifying the part that has been weathered or the material properties that have been changed, as well as the basis for determining weathered speed or weathered depth. Weathered depth is also used to determine the strengthening methods and reinforcing depth of stone carving and grottoes. To obtain the weathered depth of Yungang Grottoes, an intelligent and efficient regression forecasting support vector machines (SVM) model based on terahertz spectra is established. Terahertz time domain spectroscopy (THz-TDS) is used to measure the terahertz spectra of the Yungang Grottoes. The transmission spectra of all samples are then analyzed. Only minor differences among the transmission spectra of different samples and no characteristic absorption peaks have been observed. The SVM model based on the transmission spectra of samples is applied to distinguish and predict the depth. The results are in accordance with the real depth, and the relative errors are less than 0.85%. The results indicate that the spectra-based model can distinguish samples of Yungang Grottoes and effectively predict their depths, which can provide an important reference for the repair of the Yungang Grottoes. [ABSTRACT FROM AUTHOR]

Vinegar is a kind of fermented food condiments, which includes many regional products and involves abundant microbial resources. However, spontaneous fermentation cannot ensure consistent quality of vinegar, relatively little is known about the complexity of the microbiota involved in quality. Therefore, this review aim to explore that the role of microbiota in sediments, flavor compounds and bioactive substances. On this basis, we determined that raw materials, initial microbial composition and environmental factors are the driving forces of the fermentation process. Furthermore, we have revealed the core microorganism reaction mechanism under the driving forces. It can guide the design of the microbiota for vinegar fermentation, and to ensure the consistent of vinegar quality. This review will provide control strategies to monitor, control, and improve the safety, flavor, and health benefits of vinegar. [Display omitted] • To reveal the microbial metabolic network of vinegar quality. • The driving forces affecting the spontaneous fermentation are put forward. • The control biotransformation mechanisms through driving forces are obtained. • Driving forces physiological feedback guides the design of core microorganisms. [ABSTRACT FROM AUTHOR]

Steam explosion (SE) can improve the degradation efficiency of macromolecules such as defatted soybean meal (DSM). In this study, the physicochemical properties and the fermentation characteristics of SE-pretreated DSM were investigated. As shown by scanning electron microscopy (SEM), the dense structure of DSM was clearly cracked with larger voids. Under the pressure of 1.5 MPa, cellulose and hemicellulose were degraded by 50.7% and 71.1% respectively. When DSM treated with different SE pressure was applied to the soy sauce fermentation process, the content of amino acid nitrogen was increased 2-folds higher compared to the control, and the fermentation time has been greatly reduced. Simultaneously, the alcohols content of SS-1.5 sample was more than three times that of the control, particularly in the production of higher alcohols such as 2-methyl-1-butanol. The aldehydes, which contribute to the fruity and smoky-like aroma of soy sauce, increased significantly in both content and types (e.g., decanal, isobutyraldehyde, and 2-methylbutyraldehyde). The typical umami flavor and sauce-like aroma of soy sauce were considerably improved after SE-pretreated DSM. Taken together, SE pretreatment improved the utilization rate of raw materials and the quality of soy sauce flavor. [Display omitted] • Steam explosion (SE) destroys the structure of defatted soybean meal (DSM). • SE pretreatment enhances the soy sauce volatile flavor compounds. • SE pretreatment shortens the fermentation time of soy sauce by half. • The contents of reducing sugar and amino acid nitrogen were increased. [ABSTRACT FROM AUTHOR]

The presence of gas-producing bacteria in sufu will cause the package swelling, thus significantly affecting the storage period and sensory quality of sufu. This study aimed to isolate and identify the gas-producing bacteria in sufu and provide an effective method to control their growth. The gas-producing bacteria were isolated in sufu and identified as Weissella confusa and Weissella koreensis based on 16S rDNA. W. confusa and W. koreensis still grow and produce gas in MRS broth with a salinity of 10% oralcohol of 11% content. Nisin and Lactococcus lacti s were able to inhibit the growth of W. confusa and W. koreensis, while no inhibition was observed when sodium propionate, sodium dehydroacetate, and ε-polylysine hydrochloride were used. When the salinity and alcohol content was 6%, the growth of W. confusa was inhibited at MICs of nisin of 0.250 mg mL−1 and 0.125 mg mL−1, while the growth of W. koreensis was inhibited to 0.125 mg mL−1 and 0.063 mg mL−1. Nisin and L. lactis induced changes in cell morphology by disrupting membrane integrity of gas-producing bacteria. This study guides the sufu enterprises to adopt effective measures controlling the package swelling of sufu production and extending the products' storage period. ● Two gas-producing bacteria were isolated and identified in sufu. ● Weissella confuse and Weissella koreensis were tolerance in salinity of 10% or alcohol of 11% content. ● Nisin and Lactococcus lactis inhibited the growth of gas-producing bacteria ● Nisin and L. lactis disrupted the cell membrane integrity of gas-producing bacteria [ABSTRACT FROM AUTHOR]

Abstract: The interactions between metal ions and hydroxyl groups of carbohydrates are important for their possible biological activities. Here two HoCl3–galactitol complexes ([Ho(galac)(H2O)3)]Cl3·0.5galac) (HoG(I)) and ([Ho2(galac)(H2O)12)]Cl6·2H2O) (HoG(II))) and one ErCl3–galactitol complex ([Er(galac)(H2O)3)]Cl3·0.5galac)(ErG)) were prepared and characterized. The possible structures of HoG(I) and ErG were deduced from FTIR, elemental analysis, ESI-MS, FIR, THz and TGA results. It is suggested that Ho3+ or Er3+ is 9-coordinated with six hydroxyl groups from two galactitol molecules and three water molecules, and another galactitol molecule is hydrogen-bonded in HoG(I) and ErG and the ratio of metal to ligand is 1:1.5. The structure of HoG(II) was determined by FTIR and X-ray diffraction analyses. The results demonstrate that lanthanide ions with galactitol may form two compounds in a system and different topological structures can be obtained. [Copyright &y& Elsevier]

Acidic vinegar residue (VR) and toxic hexavalent chromium (Cr(VI)) are unfavorable substances due to their toxicity against the environment. In this study, modified biochar was prepared to investigate the removal mechanisms of Cr(VI). The results showed that ZnCl 2 could yield highly aromatic products with improved pore structures. The adsorption capacity of modified biochar reached the highest efficiency (236.81 mg g−1) when the mass ratio of ZnCl 2 /VR was 1, which is higher than the control (9.96 mg g−1). In addition, Cr(VI) adsorption coexisted with physical and chemical adsorption. The mechanisms of modified biochar to Cr(VI) removal included electrostatic attraction, pore filing, reduction and surface complexation. Notably, as a fermented product, VR biochar was a nitrogen-rich product; the formation of the amino group could provide a direct solid site for Cr(VI) adsorption. Subsequently, amorphous silica could be converted into silanol to provide additional adsorption sites. This work establishes the theoretical basis for efficient Cr(VI) removal and VR reuse. [Display omitted] • Vinegar residue biochar (VB) is nitrogen and silicon-rich product. • ZnCl 2 can inhibit the production of toxic nitriles in biochar. • Modified VB exhibits excellent ability to remove Cr (VI) (236.81 mg g−1). • Si-O of VB can be converted into Si-OH to provide indirect adsorption sites. • Mechanisms of Cr(VI) removal included physical and chemical adsorption. [ABSTRACT FROM AUTHOR]

The terahertz metamaterial sensor with high sensing performance are presented. The methods to improve the sensing performance are proposed, including (a) using different mode coupling or introduce asymmetry to form resonance peaks; (b) substrate with low permittivity, thin thickness, and low loss; (c) metal with high conductivity and thickness beyond two times skin-depth. It is proven that the electromagnetically induced transparent (EIT)-like resonance is a good candidate to get the higher sensing performance. The EIT-like resonance is formed by two coupled oscillators with the larger difference of the resonance linewidths. The double split resonant rings (DSRR) as the two coupled oscillators are designed and analyzed. The stimulated results show the length and width of the unit cell of DSRR have the most significant effect on the EIT-like resonance, followed by the gap and the period of unit cell, which agree with the theoretical analysis. The effect of four spatial arranged macrocell metamaterials consisting of multi-DSRRs on EIT-like resonance is investigated. In comparison, the diagonal arranged metamaterial has the higher sensing performance. It is pointed out the figure of merit is more suitable to evaluate the sensing performance of the metamaterial in applications. Our research provides a good reference for the design, optimization, and evaluation of THz metamaterial sensors with the high performance. • The terahertz metamaterial sensors using different mode coupling to form EIT resonance peaks are designed and optimized. • The methods to improve the sensing performance are proposed. • The double split resonant rings (DSRR) as the EIT-like resonance are analyzed. • The effect of four spatial arranged macrocell metamaterials consisting of multi-DSRRs on EIT-like resonance is compared. [ABSTRACT FROM AUTHOR]

The addition of soy sauce residue (SSR) during soybean paste fermentation usually reduces the flavor quality due to high content of fibers. Steam explosion (SE) pretreatment is an effective way to promote the fiber degradation. In this study, SE-pretreated SSR was investigated and exploited during soybean paste fermentation. SE pretreatment increased the numbers of holes and the surface irregularity, resulting in a more pronounced wrinkled surface and looser internal structure than other pretreatments. Over half of cellulose and 10 percentage of hemicellulose were released from the dense structure of SE-pretreated SSR. The addition of 3–10 percentage of the SE-pretreated SSR was more suitable for soybean paste fermentation. The flavor formation of SSR during soybean paste fermentation was enhanced by SE pretreatment. In brief, SE pretreatment of SSR improve the quality of soybean paste. • The dense structure of soy sauce residue was destroyed by steam explosion (SE). • A clearer wrinkled surface and looser inner structure can be formed by SE. • More cellulose and hemicellulose were exposed by SE pretreatment. • Soybean paste flavor was improved by adding 3–10% SE pretreated soy sauce residue. • SE pretreated soy sauce residue was more suitable for soybean paste fermentation. [ABSTRACT FROM AUTHOR]

• Tetragenococcus is the dominant microorganism in Beitang shrimp paste (BSP). • The bacterial community structures of BSP fermented by whole shrimp were similar. • Psychrobacter is closely related to the ester characteristics in H. • Halanaerobium and Streptococcus promotes the production of pyrazine in S. • Tetragenococcus is correlated with acids which improved the sour aroma of M. Beitang shrimp paste (BSP) is fermented by different parts of shrimp, such as the head (H), meat (M), or the whole shrimp (S and W). Microbial communities of BSP were dominated by Firmicutes and Proteobacteria at the phyla level and Tetragenococcus at the genus level. However, the microbial diversity of M was the lowest than the others. Non-dominant bacterial communities were presented by a mutual symbiotic model in BSP fermentation. Tetragenococcus , Halanaerobium , Streptococcus , and Brevundimonas were positively correlated with the biosynthesis of amino acids, fatty acids, and metabolic cofactors; Marinilactibacillus and Pseudomonas might be the main contributors to inorganic sulfides, nitrogen oxides, and long-chain alkanes in BSP; Psychrobacter was closely related to the ester characteristics of methyl palmitoleate and methyl hexadecanoate in H. Halanaerobium and Streptococcus promoted the production of pyrazines in S. Tetragenococcus was positively correlated with acetic acid, decanoic acid, and palmitic acid that improved the sour aroma of M. The relationship between bacteria and aroma formation under different raw materials was expected to improve the quality of BSP. [ABSTRACT FROM AUTHOR]

• A new zigzag model is developed for accurate analysis of laminated beams. • A new method is presented to determine layerwise constants in strain shape function. • The model can provide C z 0 quadratic shear stress results by constitutive equations. This paper proposes a new third-order zigzag model for asymmetric and symmetric laminated composite beams. In the framework of a general displacement form, a new zigzag shear strain shape function with layerwise coefficients corresponding to constant, linear, quadratic and cubic terms is proposed. By comparing transverse shear stress fields obtained by constitutive and equilibrium equations respectively, layerwise constants of quadratic and cubic terms are determined. With further consideration of interlaminar continuity and free stress conditions on traction free surfaces, other coefficients are achieved. As interlaminar continuity and dissimilar characteristics between layers are fully considered, the present model which has only three unknowns can accurately describe zigzag effects and provide C z 0 quadratic distribution results of transverse shear stress field by constitutive equations directly. Characteristics and advantages of the present model are discussed by comparing with other classical theoretical models. Moreover, governing equations are formulated using the principle of minimum potential energy, and analytical and finite element solutions for static analysis of laminated beams are presented. Lastly, numerical validations are presented, and comparisons with exact solutions, other theoretical models and high-fidelity finite element models well demonstrate accuracy and effectiveness of the present model for laminated beams with different features. [ABSTRACT FROM AUTHOR]

• Analysis to confirm the two ozone degradation products of DON. • Established the method to screening and monitoring of DON and ozonation products. • Investigated the characteristics of the DON and degradation products during ozonation. Deoxynivalenol (DON) is a secondary metabolite produced by Fusarium species in cereals that can be harmful to the health of humans and animals. In this work, a treatment system of aqueous ozone hybrid hydroxyl free radical (·OH) was establishedto degrade DON. An ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF) method was applied to detect and follow the fate of DON throughout the degradation process. The electrospray ionization mass spectrometry (ESI/MS) analysis confirmed the presence of DON and two degradation products (at 313.0215 and 325.0101 m / z) with the secondary mass spectrogram in the ESI positive mode. Based on the ESI/MS data, a multiple reaction monitoring (MRM) method was established to screen and monitor DON and the two degradation products in contaminated wheat. The MRM method was applied to analyze the degree of DON degradation in the samples. Overall, this work investigated the characteristics of DON and products in the ozone degradation process, and provided new insights into the application of an aqueous ozone system for the detoxification of mycotoxin-contaminated cereals. [ABSTRACT FROM AUTHOR]

In this study, the influence and relationship between the microbial structure composition at different spatial locations during soy sauce fermentation and the quality of soy sauce were investigated. Within 3-7 days of fermentation, the abundance of Chromohalobacter in the surface and upper layers of moromi was initially high but subsequently decreased. In contrast, Tetragenococcus exhibited low abundance on the surface of moromi at the beginning of fermentation but emerged as the absolute dominant bacteria by the end of the fermentation process. Throughout the fermentation period of 3-42 days, Staphylococcus and Bacillus were the predominant bacterial genera observed at the bottom of the moromi. In addition, Halanaerobium was the dominant bacterial genus in the crude soy sauce layer throughout the fermentation process. Tetragenococcus and Zygosaccharomyces were strongly positively correlated with total acid and ammonia nitrogen. Bacillus and Staphylococcus were significantly negatively correlated with the salt content., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The surface wettability of rocks in underground reservoirs affects the distribution of fluids in the reservoir, so the wettability of reservoir minerals is a key factor for crude oil recovery from reservoirs. In this paper, the wettability of quartz sand with different particle sizes in different polar solvents was determined by Washburn's capillary rise method, and the C ·cos θ values were calculated first. Next, the experimentally obtained macroscopic contact angle of water on the quartz surface of 15.0° was substituted into C ·cos θ to obtain a linear equation between the particle size of quartz sand and the capillary constant C . The particle sizes of oil sand and mineral powder were then substituted into the equation to obtain their capillary constants C . Then, based on the Owens-Wendt-Rabel-Kaelbe (OWRK) equation and the obtained contact angles of solvent on quartz sand, oil sand, and mineral powder, the surface free energy of quartz sand with different particle sizes is calculated as 76.09, 76.65, and 76.42 mN/m, respectively, which are close to the literature results. In addition, the surface free energy of oil sand with different particle sizes was 23.22, 23.45, and 23.63 mN/m, and the results indicated that the polarity of oil sand was low. Meanwhile, the surface free energies of kaolinite, illite, feldspar, and montmorillonite were 61.59, 32.85, 35.87, and 25.91 mN/m, respectively. By the improved Washburn method in this paper, the wettability of different solvents on the surface of reservoir rocks was investigated, and the surface free energy of specific solid particles was calculated, which is important for studying the extraction of crude oil from subsurface reservoir rocks., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Skin pain resulting from mechanical compression is one of the most common pains in daily life and the indispensable information for electronic skin to perceive external signals. The external mechanical stimuli are transduced into impulses and transmitted via nerve fiber, and finally, the sensation is perceived via the procession of the nerve system. However, the mathematical mechanism for pain sensation due to mechanical stimuli remains unclear. In this paper, a mathematical model for skin pain sensation under compression is established, in which the Flament solution, the revised Hodgkin-Huxley model, and the mathematical model gate control theory are considered simultaneously. The proposed model includes three parts: a mechanical model of skin compression, a model of transduction, and a model of modulation and perception. It is demonstrated that the pain sensation degree increases with the compression amplitude and decreases with deeper nociceptor location in the skin. With the help of the proposed model, the quantitative relationship between compression pain sensation and external mechanical stimuli is revealed, which has a significant benefit in promoting the design and mechanism research of electronic skin with pain perception function.

Single-crystal structures of myo -inositol complexes with erbium ([Er 2 (C 6 H 11 O 6 ) 2 (H 2 O) 5 Cl 2 ]Cl 2 (H 2 O) 4 , denoted ErI hereafter) and strontium (Sr(C 6 H 12 O 6 ) 2 (H 2 O) 2 Cl 2 , denoted SrI hereafter) are described. In ErI, deprotonation occurs on an OH of myo -inositol, although the complex is synthesized in an acidic solution, and the p K a values of all of the OHs in myo -inositol are larger than 12. The deprotonated OH is involved in a μ 2 -bridge. The polarization from two Er 3+ ions activates the chemically relatively inert OH and promotes deprotonation. In the stable conformation of myo -inositol, there are five equatorial OHs and one axial OH. The deprotonation occurs on the only axial OH, suggesting that the deprotonation possesses characteristics of regioselectivity/chiral selectivity. Two Er 3+ ions in the μ 2 -bridge are stabilized by five-membered rings formed by chelating Er 3+ with an O-C-C-O moiety. As revealed by the X-ray crystallography study, the absolute values of the O-C-C-O torsion angles decrease from ∼60 to ∼45° upon chelating. Since the O-C-C-O moiety is within a six-membered ring, the variation of the torsion angle may exert distortion of the chair conformation. Quantum chemistry calculation results indicate that an axial OH flanked by two equatorial OHs (double ax-eq motif) is favorable for the formation of a μ 2 -bridge, accounting for the selectivity. The double ax-eq motif may be used in a rational design of high-performance catalysts where deprotonation with high regioselectivity/chiral selectivity is carried out.

Single-crystal structures of five lanthanide-erythritol complexes are reported. The analysis of the chemical compositions and scrutinization of structural features in the single-crystal data of the complexes led us to find that unexpected deprotonation occurs on the OH group of erythritol of three complexes. Considering these complexes were prepared in acidic environments, where spontaneous ionization on an OH group is suppressed, we suggest metal ions play an important role in promoting the proton transfer. To find out why the chemically inert OH is activated, the single-crystal structures of 63 rare-earth complexes containing organic ligands with multiple hydroxyl groups (OLMHs) were surveyed. The formation of μ 2 -bridges turns out to be directly relevant to the occurrence of deprotonation. When an OH group from an OLMH molecule participates in the formation of a μ 2 -bridge, the polarization ability of the metal ions becomes strong enough to promote the deprotonation on the OH group. The above structural characteristics may be useful in the rational design of catalysts that can activate the chemically inert OH group and promote the relevant chemical conversions.

Japanese soy sauce has become more acceptable by Chinese consumers due to its umami taste. However, the volatile flavor compounds and taste characters have not been fully clarified. This study aimed to explore the flavor characteristics of three kinds of Japanese soy sauce, including Koikuchi Shoyu, Usukuchi Shoyu, and Amakuchi Shoyu. The secret of volatile flavor substances was investigated by Gas Chromatography-Mass Spectrometry (GC-MS) and electronic nose, while taste compounds were investigated by silylation GC-MS and electronic tongue (E-tongue). A total of 173 volatile flavor substances and 160 taste compounds were identified. In addition, 28 aroma compounds with odor activity values (OAV) ≥ 1 were considered as the typical flavors. We found that alcohols and aldehydes were in high abundance in Japanese soy sauce, but only a small portion of pyrazines and esters were. Based on electronic nose and GC-MS analysis, Koikuchi Shoyu gives more contribution to aroma compounds, while Usukuchi Shoyu and Amakuchi Shoyu give the sourness and sweetness features based on E-tongue and silylation GC-MS analysis. In this study, 50 kinds of sugars were detected that contributed to the sweetness of soy sauce. This study will provide new insight into the flavor characteristics of Japanese soy sauce that potentially contribute to the innovation and development of soy sauce., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhao, Feng, Hadiatullah, Zheng and Yao.)

Soy sauce materials of soybean meal and wheat bran were evaluated in solid-state (koji) fermentation (SSF) and submerged fermentation (SmF) by Aspergillus oryzae. Proteinase production in SSF (2331 ± 39 U g -1 ) was about 4.9 times higher than that in SmF (477 ± 13 U g -1 ), and glycoside hydrolase was approximately 2 times higher in SSF than that in SmF. In addition, protein expression of iTRAQ analysis deepens our understanding of the secreting mechanism. Abundant proteinases (dipeptidase, dipeptidyl aminopeptidase, puromycin-sensitive aminopeptidase, Xaa-pro aminopeptidase, neutral protease 2 and leucine aminopeptidase 2), along with the glycoside hydrolase (glycoamylase, glucosidase and β-xylanase) were secreted at the late stage of SSF, but tripeptidyl peptidase sed 2 was proposed as an indispensable protease in SmF or the early stage of SSF. Several metabolites associated with the carbon flux and amino acid biosynthesis were proved to be regulated by the proteinase and glycoside hydrolase production., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The coordination of carbohydrate to metal ions is important because it may be involved in many biochemical processes. The synthesis and characterization of several novel lanthanide-erythritol complexes (TbCl(3)·1.5C(4)H(10)O(4)·H(2)O (TbE(I)), Pr(NO(3))(3)·C(4)H(10)O(4)·2H(2)O (PrEN), Ce(NO(3))(3)·C(4)H(10)O(4)·2H(2)O (CeEN), Y(NO(3))(3)·C(4)H(10)O(4)·C(2)H(5)OH (YEN), Gd(NO(3))(3)·C(4)H(10)O(4)·C(2)H(5)OH (GdEN)) and Tb(NO(3))(3)·C(4)H(10)O(4)·C(2)H(5)OH (TbEN) are reported. The structures of these complexes in the solid state have been determined by X-ray diffraction. Erythritol is used as two bidentate ligands or as three hydroxyl group donor in these complexes. FTIR spectra indicate that two kinds of structures, with water and without water involved in the coordination sphere, were observed for lanthanide nitrate-erythritol complexes. FIR and THz spectra show the formation of metal ion-erythritol complexes. Luminescence spectra of Tb-erythritol complexes have the characteristics of the Tb ion.

The new technique of interspecific hybridization was created in Gossypium which could remarkably overcome abortion of interspecific hybridization and hybrid sterility of F(1). A large number of germplasm resources were obtained from seventy cross combinations among the cultivated species and between the cultivated and the 14 wild species, respectively. 8 varieties have been developed, of which 4 were from the cross combination of G. hirsutum x G. arboretum and the other are the first breed from the hybrids between G. hirsutum and 4 wild species, respectively. Of them Shiyuan 321 (jimian 24) is a new variety which had the highest increase in the national Yellow River Valley Regional test, with planting area added up to 933333 ha in the recent three years. The breeding system of interspecific hybridization was established.