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BackgroundMushrooms are considered as next-generation healthy food components. Owing to their low-fat content, high-quality proteins, dietary fiber, and rich source of nutraceuticals. They are ideally preferred in formulation of low-caloric functional foods. In this view, the breeding strategies of mushroom Auricularia cornea (A. cornea) focusing on high yield and higher quality with rich nutritional values and health benefits are still needed.Materials and methodsA total of 50 strains of A. cornea were used to analyze the bio efficiency and the time required for fruiting body formation following the cultivation experiment. The calorimetric method was used to evaluate the antioxidant activity and quantify the crude polysaccharides and minerals content thereafter.ResultsThe results showed that the time required for fruiting body formation and biological efficiency varied significantly among the selected strains. Noticeably, the wild domesticated strain Ac13 of A. cornea mushroom showed the shortest fruit development time (80 days). Similarly, the hybrid strains including Ac3 and Ac15 possessed the highest biological efficiency (82.40 and 94.84%). Hybrid strains Ac18 (15.2%) and cultivated strains Ac33 (15.6%) showed the highest content of crude polysaccharides, while cultivated strains Ac1 and Ac33, demonstrated the highest content of total polysaccharides in the fruiting body (216 mg. g−1 and 200 mg. g−1). In the case of mineral content, the highest zinc contents were observed from the cultivated strain Ac46 (486.33 mg·kg−1). The maximum iron content was detected from the hybrid strain Ac3 (788 mg·kg−1), and the wild domesticated strain Ac28 (350 mg·kg−1). The crude polysaccharides of the A. cornea strain showed significant antioxidant potential, and the ability of Ac33 and Ac24 to scavenge DPPH radicals and ABTS, which was significantly improved compared to other strains, respectively. Principal component analysis was applied to examine the agronomic traits and chemical compounds of various strains of A. cornea mushrooms. The results revealed that cultivated, wild domesticated, and hybrid strains of A. cornea exhibited distinct characteristics in terms of growth, yield, and nutritional properties.ConclusionThe crude polysaccharides from A. cornea mushroom strains act as natural antioxidants, the wild, hybrid, and commercial A. cornea mushroom strains can achieve rapid growth, early maturation, and high yields. The evaluation of biochemical indexes and nutritional characteristics of strains with excellent traits provided a scientific basis for initiating high-quality breeding, provided germplasm resources for the production of “functional food” with real nutritional and health value.

Gloeostereum incarnatum has edible and medicinal value and was first cultivated and domesticated in China. We sequenced the G. incarnatum monokaryotic strain GiC-126 on an Illumina HiSeq X Ten system and obtained a 34.52-Mb genome assembly sequence that encoded 16,895 predicted genes. We combined the GiC-126 genome with the published genome of G. incarnatum strain CCMJ2665 to construct a genetic linkage map (GiC-126 genome) that had 10 linkage groups (LGs), and the 15 assembly sequences of CCMJ2665 were integrated into 8 LGs. We identified 1912 simple sequence repeat (SSR) loci and detected 700 genes containing 768 SSRs in the genome; 65 and 100 of them were annotated with gene ontology (GO) terms and KEGG pathways, respectively. Carbohydrate-active enzymes (CAZymes) were identified in 20 fungal genomes and annotated; among them, 144 CAZymes were annotated in the GiC-126 genome. The A mating-type locus (MAT-A) of G. incarnatum was located on scaffold885 at 38.9 cM of LG1 and was flanked by two homeodomain (HD1) genes, mip and beta-fg. Fourteen segregation distortion markers were detected in the genetic linkage map, all of which were skewed toward the parent GiC-126. They formed three segregation distortion regions (SDR1–SDR3), and 22 predictive genes were found in scaffold1920 where three segregation distortion markers were located in SDR1. In this study, we corrected and updated the genomic information of G. incarnatum. Our results will provide a theoretical basis for fine gene mapping, functional gene cloning, and genetic breeding the follow-up of G. incarnatum.

The sharp change of stiffness in the soil-rock combination stratum is the weak point in the seismic design of the tunnel structure. To explore the influence of soil-rock combination stratum vibration on the shield tunnel, the section of Jinan rail transit line 4 at the Olympic Sports Center is used as the research background. Firstly, the two-dimensional numerical model is established, and the internal force calculation and distribution law of the structure are studied. Then, based on the third similarity theory, the model similarity physical relationship is derived. The shaking-table model test of the soil-rock-structure system is carried out. The seismic response law of tunnel cross-section is studied by the model test and numerical analysis. The results revealed the following: (1) the peak bending moment distribution diagram derived from numerical calculation is consistent with that obtained from the shaking-table model test, which has shown that the numerical and experimental methods are correct, and the research results are available for the seismic resistance of shield tunnels. (2) The deformation, axial force, shear force, and bending moment of the tunnel structure in the soil-rock combination stratum under the action of S-wave change abruptly and significantly at the soil-rock interface section, and the difference in structural stress between the upper and lower sides of the soil-rock interface increased by 65.5%. The excessive stress difference changes the damage mode of the tunnel. (3) The relative difference and abrupt change of bending moment and shear force at the interface is more significant than the axial force, so that the tunnel structure at the soil-rock interface is most prone to bending-shear damage.

This paper couples Li–He’s homotopy perturbation method with the energy method to obtain an approximate solution of a tangent nonlinear packaging system. A higher order homotopy equation is constructed by adopting the basic idea of the Li–He’s homotopy perturbation method. The energy method is used to improve the maximal displacement and the frequency of the system to an ever higher accuracy. Comparison with the numerical solution obtained by the Runge–Kutta method shows that the shock responses of the system solved by the new method are more effective with a relative error of 0.15%.

The compressive densification strain of honeycomb paperboard is one of the important parameters which affect the energy absorption property of honeycomb paperboard. The in-plane bearing mechanism of honeycomb paperboard in plastic zone was analyzed based on compression tests of the single row and multi-rows of honeycomb paperboard. The result indicates that the core layer plays a supporting role in resisting the buckling of the face layer. The double inner folds are formed in machine direction and the symmetrical inner folds are formed in cross direction in a honeycomb core. The core single wall and the face layer play a critical role in the load bearing in machine direction, and the core double walls, core single wall, and face layer all play critical roles in the load bearing in cross direction. On this basis, the evaluation equation of the compressive densification strain was obtained based on the energy absorption efficiency method and geometric scale effect, which are verified so that the experiment and test results are in good agreement.

The fruiting body pattern is an important agronomic trait of the edible fungus Auricularia auricula-judae, and an important breeding target. There are two types of fruiting body pattern: the cluster type and the chrysanthemum type. We identified the fruiting body pattern of 26 test strains, and then constructed two different near-isogenic pools. Then, we developed sequence characterized amplified region (SCAR) molecular markers associated with the fruiting body pattern based on sequence-related amplified polymorphism (SRAP) markers. Ten different bands (189–522 bp) were amplified using 153 pairs of SRAP primers. The SCAR marker “SCL-18” consisted of a single 522-bp band amplified from the cluster-type strains, but not the chrysanthemum strains. This SCAR marker was closely associated with the cluster-type fruiting body trait of A. auricula-judae. These results lay the foundation for further research to locate and clone genes controlling the fruiting body pattern of A. auricula-judae.

Technological advances in unmanned aerial vehicles (UAVs) have made it possible to employ drone deliveries for packaged products, but currently no standards of practice are available to qualify packaged products traveling through this distribution channel. This research proposes a methodology to collect field data from a UAV to develop simulation techniques for use with package testing equipment. This project utilized data recorders to measure the vibration, shock, and atmospheric field data on two models of the DJI drones. The root mean square G value (Grms), the power spectral density (PSD), maximum G-values and shock response spectrum, and atmospheric data were reported in this study. The study found that the general shape of the PSD profile of the drones differed from the PSD air profiles of the aircraft. The overall recorded Grms levels of the drones were also significantly higher than those of the published air profile of the aircraft. Moreover, the study found that the drone’s in-flight vibration intensities in the horizontal level were consistently higher than those in the vertical direction. The major sources of vibration and shock in both drones’ models originated from the two-propeller rotations. Shocks recorded during the flight reached 14 G, took place in the horizontal plane with the drone accelerating as opposed to the vertical plane where the drone is landing.

Calcium alginate based controlled release films with moderate mechanical properties were fabricated in this paper. The diffusion mechanism of these films contacting food simulating solvent (FSS) was explored in some detail. With the increase of glycerol content, the diffusion coefficient (D) values of cinnamon essential oils (CEOs) diffusing to ethanol first increased slowly (0.3–0.6 mL), then vigorously (0.6–0.9 mL), and then mildly (0.9–1.2 mL). The D values of the CEOs diffused to water are all in the order of magnitude of 10−10 cm2/s. The D values of CEOs diffused from films EG3 and EGC1 to aqueous ethanol altered enormously at a small moisture percentage (w = 0.3), then continuously varied vigorously, and at last altered mildly in the range of w = 0.3–1. All the results above indicate that, considering the FSS, the diffusion ability of molecules is jointly determined by the size and distribution of free volume in the system (polymer + diffusive substance + solvents), the intermolecular interaction, and the partition coefficient of the solvents. In addition, several pairs of D values, such as DEG and DGA, are very close to each other, indicating that different kinds of interactions between different groups may have the same effect on the diffusion ability of molecules. The correlation between D1 and D2 indicates that polymeric emulsifier chains also exist in the polymer-rich layer. All the findings and analysis could provide the theoretical basis and data support for further molecular dynamic simulation and could guide the design of controlled release food packaging for food protection.

New-builtbridges andold bridges in inland waterwaysnear layout,the intersects angle that the normal direction of bridges axes andthe flow directionis more than 5, it is an important issuethat the navigable effective widthis determinedscientificallyand reasonably to ensure the safety of ships and bridge.In this paper, navigable effective clearance widthof two bridges as a wholeare calculated based on channel conditions and pier layout,which calculate the navigable effective width in the channel direction by oblique projection, determine the turbulence width by physical model test, graphicsand compare. Finally, taking the Lijiatuo Yangtze River secondbridge project in Chongqing as an example, the scientific and rationality of this method is verified, which can provide reference for the determination of navigable effective clearance widthof similar bridges in the future.

To evaluate the shock characteristics of critical component for a nonlinear packaging system, a new concept of three-dimensional shock spectrum was proposed. Three key coordinate parameters, such as the nondimensional pulse duration, the frequency parameter ratio and the ratio of the maximum response acceleration to the peak pulse acceleration, were governed in a novel dynamical mathematical model. It is shown that the shock response of critical component is weakened owning to the decrease in the defined system parameter. Furthermore, at low frequency parameter ratio, the enhancement of the damping ratio of the critical component leads to the decrease in the peak of the shock response, which can also be reduced by the increase in damping ratio of cushioning pad at both lower and higher frequency parameter ratios. The discussion and analysis provide some insights into the design of cushioning packaging as well.

The effect of fatigue damage (FD) on the energy absorption properties of precompressed honeycomb paperboard is investigated by fatigue compression experiments. The constitutive relations of honeycomb paperboard have been changed after the fatigue damage. The results show that FD has effect on plateau stress and energy absorption capacity of honeycomb paperboard after fatigue cycles but has no significant effect on densification strain. Energy absorption diagram based on the effect of FD is constructed from the stress-strain curves obtained after fatigue compression experiments. FD is a significant consideration for honeycomb paperboard after transports. The results of this paper could be used for optimization design of packaging materials.

The aim of this paper is to develop a new frequency response function- (FRF-) based indirect inverse substructuring method without measuring system-level FRFs in the coupling DOFs for the analysis of the dynamic characteristics of a three-substructure coupled product transport system with rigid and flexible coupling. By enforcing the dynamic equilibrium conditions at the coupling coordinates and the displacement compatibility conditions, a closed-form analytical solution to inverse substructuring analysis of multisubstructure coupled product transport system is derived based on the relationship of easy-to-monitor component-level FRFs and the system-level FRFs at the coupling coordinates. The proposed method is validated by a lumped mass-spring-damper model, and the predicted coupling dynamic stiffness is compared with the direct computation, showing exact agreement. The method developed offers an approach to predict the unknown coupling dynamic stiffness from measured FRFs purely. The suggested method may help to obtain the main controlling factors and contributions from the various structure-borne paths for product transport system.

A polynomial model was suggested for precompressed honeycomb paperboard packaging system, and then both of the inner-resonance conditions for packaged product and the critical component were obtained applying the variational approach. Finally, the effect of fatigue damage on the inner resonance conditions was discussed. The results show that both the packaged product and critical component can be damaged by inner-resonance when some conditions required were met, and the fatigue of honeycomb paperboard will obviously affect the inner-resonance conditions.

A frequency response function- (FRF-) based direct decoupling method is proposed and applied to inverse analysis of a multicoordinate coupled system. The general formulation of inverse substructuring method for multicoordinate coupled multisubstructure system is derived. The proposed method is validated by a lumped mass-spring-damper model; the predicted FRFs of substructures are compared with the direct computations, showing exact agreement. The developed method offers an approach to back out the unknown substructure-level FRFs from purely system-level FRFs.

A dynamic model is proposed for a polymer foam-based nonlinear cushioning system. An accurate analytical solution for the nonlinear free vibration of the system is derived by applying He's variational iteration method, and conditions for resonance are obtained, which should be avoided in the cushioning design.

BACKGROUND: As one of the most abundant and destructive pests in agriculture, aphids cause significant damage to crops due to their sap‐taking and as virus vectors. Chemical insecticides are the most effective method to control aphids, but they bring insecticide resistance problems and harm nontarget organisms, especially bees, therefore the search for novel eco‐friendly aphid control agents with low bee toxicity is urgent. Insect kinins are a class of small neuropeptides that control important functions in insects. In our previous study, we found insect kinin analog IV‐3 has good aphicidal activity and the location of the aromatic ring on the side chain of Phe2 is the key to the formation of the β‐turn resulting in the biological activity of insect kinin analogs. However, there are few studies on insect kinin Phe2 substitution and modification, and its structure–activity relationship is still unclear. RESULTS: In this project, 44 insect kinin analogs with the Phe2 modification, replacing it with different natural or unnatural amino acids, were designed and synthesized based on the lead IV‐3 to explore the role of the Phe2 residues. Bioassays with soybean aphids of Aphis glycines indicated that nine analogs have better aphicidal activity than the lead IV‐3. In particular, compound L25 exhibits excellent aphicidal activity (LC50 = 0.0047 mmol L−1) and has low toxicity to bees. Furthermore, a reliable three‐dimensional quantitative structure–activity relationship (3D‐QSAR) was established to produce a helpful clue that introducing hydrophobic groups away from the backbone chain is beneficial to improve aphicidal activity. CONCLUSION: The residue Phe2 of insect kinin analogs is the key position and has a significant impact on the activity. L25 has a high toxicity for aphids, while a low toxicity to bees, and therefore can be considered as a lead compound to develop new biosafe aphid control agents. Finally, we provide a useful 3D‐QSAR model as theoretical guidance for further structural optimization. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]