Search Results (11)

Morels (Morchella spp.) are medicinal and edible mushrooms, renowned for their distinctive taste and appearance. Due to the low yields and difficulty of foraging wild morels, artificial cultivation has significant economic value. Outdoor cultivation yields are influenced by factors such as weather and diseases, which can result in crop instability or failure, thereby causing losses to farmers. Previous studies have typically concentrated on either the fungal or bacterial communities. In this study, we investigated the ecological relationships between morel growth and both the fungi and bacteria in soil, analyzed over multiple trophic levels. We investigated three soil types: soil in which morel death was observed (DM), soil in which no morels emerged (UM), and soil that is suitable for normal fruiting (NM). We used high-throughput ITS and 16S rDNA amplicon sequencing, alongside assessment of soil physicochemical properties, to investigate factors contributing to morel emergence and death. The results indicated that the richness and diversity of both fungal and bacterial communities in the normal fruiting soil (NM) were significantly higher than those in the non-fruiting soils (DM and UM). The bacterial community was primarily composed of Proteobacteria and Bacteroidota, while the fungal community was dominated by Ascomycota and Mucoromycota. Furthermore, Morchella was significantly enriched in NM, indicating that it had successfully colonized and could develop into fruiting bodies. The morel mycelium in NM effectively utilized external nutrient bags, enhancing the soil nitrogen and organic matter content while reducing the consumption of available phosphorus and potassium. LEfSe and random forest analyses identified Pedobacter and Massilia as biomarkers of NM, potentially associated with the symbiosis of Morchella, which may promote its growth. Furthermore, the construction of the fungal-bacterial co-occurrence network revealed that the NM soil exhibited a higher number of nodes and greater network stability, suggesting that its complex microbial community structure may play a crucial role in the successful cultivation of Morchella. Our results indicate that the failures in morel production were due to inadequate management practices. Elevated greenhouse temperatures may have promoted pathogen proliferation, hindering the effective utilization of external nutrient bags by morel mycelium. Consequently, the mycelium was unable to accumulate nutrients efficiently, leading to the inability of Morchella to fruit or resulting in developmental failures. This study offers valuable insights into the interactions between morel mycelium and soil microorganisms, elucidating the reasons for morel cultivation failure and suggesting strategies for optimizing morel cultivation. Full article

A novel protease was isolated from the fruiting bodies of the straw mushroom Volvariella volvacea. The protease was purified 13.48-fold using a series of techniques, including ammonium sulfate precipitation, ultrafiltration, diethylaminoethyl fast-flow (DEAE FF) ion-exchange chromatography, and Superdex 75 gel filtration chromatography, resulting in a specific enzyme activity of 286.82 U/mg toward casein as a substrate. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed that the purified protease had a molecular weight of 24 kDa. The enzyme exhibited optimal activity at pH 7 and 50 °C, showing sensitivity to alkaline conditions and instability at elevated temperatures. The presence of Ca²⁺ significantly enhanced enzyme activity, whereas Ni²⁺ and Cu²⁺ exerted strong inhibitory effects, with other metal ions showing weak inhibition. β-mercaptoethanol, Tween-80, and Triton X-100 had more pronounced inhibitory effects, whereas PMSF, EDTA, and CTAB had weaker inhibitory effects. The Michaelis constant (Km) and maximum velocity (Vm) of the protease were determined to be 1.34 g/L and 3.45 μg/(mL·min), respectively. The protease exhibited a greater degree of enzymatic degradation of soybean-isolate protein (7.58%) compared to trypsin (5.24%), with the enzyme product containing a high percentage of medicinal amino acids (73.54%), particularly phenylalanine (Phe) and arginine (Arg), suggesting their presence at the enzyme’s active site. These findings suggest that the protease from V. volvacea holds promising potential for applications in the food industry, particularly in protein hydrolysate production and flavor enhancement. Full article

The flatness of the cut surface in enoki mushrooms (Flammulina filiformis Z.W. Ge, X.B. Liu & Zhu L. Yang) is a key factor in quality classification. However, conventional automatic cutting equipment struggles with deformation issues due to its inability to adjust the grasping force based on individual mushroom sizes. To address this, we propose an improved method that integrates visual feedback to dynamically adjust the execution end, enhancing cut precision. Our approach enhances YOLOv8n-seg with Star Net, SPPECAN (a reconstructed SPPF with efficient channel attention), and C2fDStar (C2f with Star Net and deformable convolution) to improve feature extraction while reducing computational complexity and feature loss. Additionally, we introduce a mask ownership judgment and merging optimization algorithm to correct positional offsets, internal disconnections, and boundary instabilities in grasping area predictions. Based on this, we optimize grasping parameters using an improved centroid-based region width measurement and establish a region width-to-PWM mapping model for the precise conversion from visual data to gripper control. Experiments in real-situation settings demonstrate the effectiveness of our method, achieving a mean average precision (mAP50:95) of 0.743 for grasping area segmentation, a 4.5% improvement over YOLOv8, with an average detection speed of 10.3 ms and a target width measurement error of only 0.14%. The proposed mapping relationship enables adaptive end-effector control, resulting in a 96% grasping success rate and a 98% qualified cutting surface rate. These results confirm the feasibility of our approach and provide a strong technical foundation for the intelligent automation of enoki mushroom cutting systems. Full article

Natural polyphenols have drawbacks such as instability and low bioavailability, which can be overcome by encapsulated slow-release systems. Natural polymer hydrogels are ideal materials for slow-release systems because of their high biocompatibility. In this study, Longzhua mushroom polysaccharide hydrogel (LMPH) was used to encapsulate rambutan peel polyphenols (RPP) and delay their release time to improve their stability and bioavailability. The mechanical properties, rheology, stability, swelling properties, water-holding capacity, RPP loading, and slow-release behavior of LMPH were investigated. The results showed that LMPH has adequate mechanical and rheological properties, high thermal stability, excellent swelling and water-holding capacity, and good self-healing behavior. Increasing the polysaccharide content not only improved the hardness (0.17–1.13 N) and water-holding capacity of LMPH (90.84–99.32%) but also enhanced the encapsulation efficiency of RPP (93.13–99.94%). The dense network structure slowed down the release of RPP. In particular, LMPH5 released only 61.58% at 48 h. Thus, a stable encapsulated slow-release system was fabricated using a simple method based on the properties of LMPH. The developed material has great potential for the sustained release and delivery of biologically active substances. Full article

Curved free shear layers emerge in many engineering problems involving complex flow geometries, such as the flow over a backward-facing step, flows with wall injection in a boundary layer, the flow inside side-dump combustors, or wakes generated by vertical axis wind turbines, among others. Previous studies involving centrifugal instabilities have mainly focused on wall-flows where Taylor instabilities between two rotating concentric cylinders or Görtler vortices in boundary layers are generated. Curved free shear layer flows, however, have not received sufficient attention, especially in the nonlinear regime. The present work investigates the development of centrifugal instabilities in a curved free shear layer flow in the nonlinear compressible regime. The compressible Navier–Stokes equations are reduced to the nonlinear boundary region equations (BREs) in a high Reynolds number asymptotic framework, wherein the streamwise wavelength of the disturbances is assumed to be much larger than the spanwise and wall-normal counterparts. We study the effect of the freestream Mach number $M_{\infty }$, the shear layer thickness $\delta$, the amplitude of the incoming disturbance A, and the relative velocity difference across the shear layer $\Delta V$ on the development of these centrifugal instabilities. Our parametric study shows that, among other things, the kinetic energy of the curved shear layer flow increases with increasing $\Delta V$ and A decreases with increasing $delta$. It was also found that increasing the disturbance amplitude of the incoming disturbance leads to significant growth in the mushroom-like structure’s amplitude and renders the secondary instability structures more prominent, indicating increased mixing for all Mach numbers under consideration. Full article

White button mushrooms yield instability in artificial cultivation, often caused by crop diseases. The main disease is wet bubble disease. The appearance of its causative agent, M. perniciosa, may lead to total yield loss. The microbiocontrol of M. perniciosa is focused on casing soil antagonist use. Since no industrial producer strains of polyfunctional biologics have been used in previous studies, our research goal was to characterize the effect of B. subtilis B-10 and M-22 on a mycopathogen and reveal its control possibilities. The reason for B. subtilis B-10 and M-22 use in mycopathogen control has been revealed by interactions between producer strains and the studying of M. perniciosa. The suppression of M. perniciosa development by producer strains was established, indicating a prolonged B-10 and M-22 effect on the mycopathogen. High biological efficacy in both strains at the early stages of mycopathogen development upon introducing them into the wells and spraying was shown: B-10—50.9–99.6% and M-22—57.5–99.2%, respectively (p ≤ 0.05). Significant differences between producer strains were not revealed, although during the first day of exposure to developed M. perniciosa colonies, M-22 showed greater activity. The high efficiency of preventive treatment when producer strains completely suppressed mycoparasite development permits us to recommend them both for introducing when preparing casing for M. perniciosa control. Full article

Astrophysical relativistic jets in active galactic nuclei, gamma-ray bursts, and pulsars is the main key subject of study in the field of high-energy astrophysics, especially regarding the jet interaction with the interstellar or intergalactic environment. In this work, we review studies of particle-in-cell simulations of relativistic electron–proton ($e^{-}-p^{+}$) and electron–positron ($e^{\pm }$) jets, and we compare simulations that we have conducted with the relativistic 3D TRISTAN-MPI code for unmagnetized and magnetized jets. We focus on how the magnetic fields affect the evolution of relativistic jets of different compositions, how the jets interact with the ambient media, how the kinetic instabilities such as the Weibel instability, the kinetic Kelvin–Helmholtz instability and the mushroom instability develop, and we discuss possible particle acceleration mechanisms at reconnection sites. Full article

Finnish non-timber forest products (NTFPs) are valued on the national and international markets. Yet, the annual marketed quantities vary considerably, causing instability in supply chains. Thus, climatic and economic factors affecting the annually aggregated supply of top-marketed mushrooms (ceps, milk caps, and chanterelle) and berries (bilberry, cowberry, and cloudberry) in Finland were studied. Data on mushroom and berry market prices (€/kg) and quantities (kg) were obtained from the statistics on annual quantities of berries and mushrooms bought by organized trade and industry in Finland (1978–2016). The species-specific supply functions were described as linear regression models, where annually aggregated quantities were predicted as a function of climatic and economic variables. Our results suggested that climatic variables influenced the marketed quantities of NTFPs through the biological yields of berries and mushrooms, and that the market price had a negative effect on the marketed quantities of ceps, milk caps, and berries. The markets for NTFPs have become more international at the second half of the study period (1999–2016), modifying the price-quantity relationships of ceps, milk caps and cloudberries. Additionally, the number of visas issued to Thai pickers increased the marketed quantities of bilberries and cowberries. Full article

The particle-in-cell (PIC) method was developed to investigate microscopic phenomena, and with the advances in computing power, newly developed codes have been used for several fields, such as astrophysical, magnetospheric, and solar plasmas. PIC applications have grown extensively, with large computing powers available on supercomputers such as Pleiades and Blue Waters in the US. For astrophysical plasma research, PIC methods have been utilized for several topics, such as reconnection, pulsar dynamics, non-relativistic shocks, relativistic shocks, and relativistic jets. PIC simulations of relativistic jets have been reviewed with emphasis placed on the physics involved in the simulations. This review summarizes PIC simulations, starting with the Weibel instability in slab models of jets, and then focuses on global jet evolution in helical magnetic field geometry. In particular, we address kinetic Kelvin-Helmholtz instabilities and mushroom instabilities. Full article

In this study, we investigate the interaction of jets with their environment at a microscopic level, which is a key open question in the study of relativistic jets. Using small simulation systems during past research, we initially studied the evolution of both electron–proton and electron–positron relativistic jets containing helical magnetic fields, by focusing on their interactions with an ambient plasma. Here, using larger jet radii, we have performed simulations of global jets containing helical magnetic fields in order to examine how helical magnetic fields affect kinetic instabilities, such as the Weibel instability, the kinetic Kelvin–Helmholtz instability (kKHI) and the mushroom instability (MI). We found that the evolution of global jets strongly depends on the size of the jet radius. For example, phase bunching of jet electrons, in particular in the electron–proton jet, is mixed with a larger jet radius as a result of the more complicated structures of magnetic fields with excited kinetic instabilities. In our simulation, these kinetic instabilities led to new types of instabilities in global jets. In the electron–proton jet simulation, a modified recollimation occurred, and jet electrons were strongly perturbed. In the electron–positron jet simulation, mixed kinetic instabilities occurred early, followed by a turbulence-like structure. Simulations using much larger (and longer) systems are required in order to further thoroughly investigate the evolution of global jets containing helical magnetic fields. Full article

In the study of relativistic jets one of the key open questions is their interaction with the environment on the microscopic level. Here, we study the initial evolution of both electron–proton ( $e^{-}$ – $p^{+}$ ) and electron–positron ( $e^{\pm }$ ) relativistic jets containing helical magnetic fields, focusing on their interaction with an ambient plasma. We have performed simulations of “global” jets containing helical magnetic fields in order to examine how helical magnetic fields affect kinetic instabilities such as the Weibel instability, the kinetic Kelvin-Helmholtz instability (kKHI) and the Mushroom instability (MI). In our initial simulation study these kinetic instabilities are suppressed and new types of instabilities can grow. In the $e^{-}$ – $p^{+}$ jet simulation a recollimation-like instability occurs and jet electrons are strongly perturbed. In the $e^{\pm }$ jet simulation a recollimation-like instability occurs at early times followed by a kinetic instability and the general structure is similar to a simulation without helical magnetic field. Simulations using much larger systems are required in order to thoroughly follow the evolution of global jets containing helical magnetic fields. Full article