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A ten-week feeding trial evaluated the feasibility of methanotroph (Methylococcus capsulatus) bacteria meal (FeedKind®, FK) as a fishmeal substitute in largemouth bass (Micropterus salmoides) diets. Six isonitrogenous and isoenergetic diets with different inclusion levels of FK (0 (fishmeal group), 43, 86, 129, 172 and 215 g/kg) were formulated to replace 0, 50, 100, 150, 200 and 250 g/kg fishmeal, respectively. The results showed that FK inclusion level could reach 129 g/kg without significantly affecting growth or feed coefficient rate (P > 0.05), while growth performance was decreased and feed coefficient rate increased when FK inclusion levels exceeded 129 g/kg (P < 0.05). Increase in FK inclusion levels tended to reduce plasma total cholesterol and total triglyceride whilst plasma total protein, albumin, alanine aminotransferase and aspartate aminotransferase in FK treatment groups were unchanged compared with fishmeal group (P > 0.05). FK inclusion levels at 43 g/kg and 86 g/kg were not detrimental to intestinal morphology whilst it was unfavourable when FK inclusion levels exceeded 86 g/kg as the total length of intestinal wall thickness and villus height, villus height were obviously decreased compared with fishmeal group (P < 0.05). As regards to inflammatory cytokine genes, FK instead of fishmeal increased the expression levels of TLR2, RelA, TNF-α, IL-1β, IL-10 and TGF-β, 43 g/kg and 86 g/kg FK decreased the expression level of Caspase-3 (P < 0.05). In conclusion, 129 g/kg FK can replace 150 g/kg fishmeal without negative effects on the growth performance, and replacing 100 g/kg fishmeal with 86 g/kg FK is more beneficial to intestinal health. • 129 g/kg FK instead of 150 g/kg fishmeal has no effect on the growth performance of juvenile largemouth bass. • FK instead of fishmeal increases the expression levels of inflammation cytokines by activating TLR2. • 86 g/kg FK instead of 100 g/kg fishmeal is more beneficial to intestinal health. [ABSTRACT FROM AUTHOR]

An improvement in the activities of daily living (ADLs) is significantly related to the quality of life and prognoses of patients with stroke. However, the factors predicting significant improvement in ADL (SI-ADL) have not yet been clarified. Therefore, we sought to identify the key factors affecting SI-ADL in patients with stroke after rehabilitation therapy using both logistic regression modeling and decision tree modeling. We retrospectively collected and analyzed the clinical data of 190 patients with stroke who underwent rehabilitation therapy at our hospital between January 2020 and July 2020. General and rehabilitation therapy data were extracted, and the Barthel index (BI) score was used for outcome assessment. We defined SI-ADL as an improvement in the BI score by 15 points or more during hospitalization. Logistic regression and decision tree models were established to explore the SI-ADL predictors. We then used receiver operating characteristic (ROC) curves to compare the logistic regression and decision tree models. Univariate analysis revealed that compared with the non-SI-ADL group, the SI-ADL group showed a significantly shorter course of stroke, longer hospital stay, and higher rate of receiving occupational and speech therapies (all P < 0.05). Binary logistic regression analysis revealed the course of stroke at admission (odds ratio OR = 0.986 , 95 % confidence interval CI = 0.979 –0.993; P < 0.001) and the length of hospital stay (OR = 1.030 , 95 % CI = 1.013 –1.047; P =0.001) as the independent predictors of SI-ADL. ROC comparisons revealed no significant differences in the areas under the curves for the logistic regression and decision tree models (0.808 vs. 0.831; z = 0.977 , P = 0.329). Both models identified the course of disease at admission and the length of hospital stay as key factors affecting SI-ADL. Early initiation of rehabilitation therapy is of immense importance for improving the ADLs in patients with stroke. [ABSTRACT FROM AUTHOR]

The role of turbulence in low-β, guide-field reconnection exhausts is explored in 2D reconnection and 2D and 3D Riemann simulations. The structure of the exhaust and associated turbulence is controlled by a pair of rotational discontinuities (RDs) at the exhaust boundary and a pair of slow shocks (SSs) that are generated by counterstreaming ions beams. In 2D, the exhaust develops large-amplitude striations at the ion Larmor radius scale that are produced by electron-beam-driven ion cyclotron waves. The electron beams driving the instability are injected into the exhaust from one of the RDs. However, in 3D Riemann simulations, the additional dimension (in the out-of-plane direction) results in strong Buneman and electron-electron streaming instabilities at the RD which suppress the electron beam formation and therefore the striations in the exhaust. The strength of the streaming instabilities at the RD is controlled by the ratio of the electron thermal speed to Alfvén speed, with the lower thermal speed being more unstable. In the 3D simulations, an ion-ion streaming instability acts to partially thermalize the counterstreaming ion beams at the SSs. This instability is controlled by the ratio of the sound speed to Alfvén speed and is expected to be stable in the low β solar corona. The results suggest that in a guide field reconnection exhaust with 1 ≫ β > m e / m i , the kinetic-scale turbulence that develops will be too weak to play a significant role in energy conversion and particle acceleration. Therefore, the energy conversion will be mostly controlled by laminar physics or multi-x-line reconnection. [ABSTRACT FROM AUTHOR]

Kinetic Riemann simulations have been completed to explore particle heating during guide field reconnection in the low-β environment of the inner heliosphere and the solar corona. The reconnection exhaust is bounded by two rotational discontinuities (RDs), and two slow shocks (SSs) form within the exhaust as in magnetohydrodynamic (MHD) models. At the RDs, ions are accelerated by the magnetic field tension to drive the reconnection outflow as well as flows in the out-of-plane direction. The out-of-plane flows stream toward the midplane and meet to drive the SSs. The SSs differ greatly from those in the MHD model. The turbulence at the shock fronts and both upstream and downstream is weak, and so the shocks are laminar and produce little dissipation. Downstream of the SSs, the counterstreaming ion beams lead to higher density, which leads to a positive potential between the SSs which acts to confine the downstream electrons to maintain charge neutrality. The potential accelerates electrons from upstream of the SSs to the downstream region and traps a small fraction but only modestly increases the downstream electron temperature above the upstream value. In the low-β limit, the released magnetic energy is split between bulk flow and ion heating with little energy going to electrons. That the model produces neither strong electron heating nor an energetic electron component suggests that other mechanisms, such as multiple x-line reconnection, are required to explain energetic electron production in large flares. The model can be tested with the expected data from the Parker Solar Probe. [ABSTRACT FROM AUTHOR]

Magnetic reconnection in the relativistic regime has been proposed as an important process for the efficient production of nonthermal particles and high-energy emission. Using fully kinetic particle-in-cell simulations, we investigate how the guide-field strength and domain size affect the characteristic spectral features and acceleration processes. We study two stages of acceleration: energization up until the injection energy γ inj and further acceleration that generates a power-law spectrum. Stronger guide fields increase the power-law index and γ inj, which suppresses acceleration efficiency. These quantities seemingly converge with increasing domain size, suggesting that our findings can be extended to large-scale systems. We find that three distinct mechanisms contribute to acceleration during injection: particle streaming along the parallel electric field, Fermi reflection, and the pickup process. The Fermi and pickup processes, related to the electric field perpendicular to the magnetic field, govern the injection for weak guide fields and larger domains. Meanwhile, parallel electric fields are important for injection in the strong guide-field regime. In the post-injection stage, we find that perpendicular electric fields dominate particle acceleration in the weak guide-field regime, whereas parallel electric fields control acceleration for strong guide fields. These findings will help explain the nonthermal acceleration and emission in high-energy astrophysics, including black hole jets and pulsar wind nebulae. [ABSTRACT FROM AUTHOR]

Four experimental trials were conducted to explore the optimal dietary protein requirement level for the genetically improved farmed tilapia (GIFT) at different seasonal growth stages. Six practical diets were prepared with graded protein levels (26.45%, 29.28%, 31.69%, 33.68%, 36.18% and 38.75%, dry basis). In Stage 1 (initial weight 3.00 g), the results showed that the optimal growth performance was observed in the 33.68% dietary protein group. Correspondingly, compared with the lowest (26.45%) or highest (38.75%) dietary protein groups, 33.68% dietary protein significantly upregulated the GH‐IGF axis‐related genes (GH, GHR1, GHR2 and IGF‐1) and TOR signalling pathway‐related genes (TOR, S6K1 and 4EBP1). In Stage 2 (initial weight 43.78 g), 26.45% dietary protein contributed to the optimum growth performance. Besides, the expression levels of GH, GHR2 and IGF‐1 and TOR signalling pathway (S6K1 and 4EBP1) decreased with the increasing dietary protein levels, and the maximum values were observed in the 26.45% dietary protein group. In Stage 3 (initial weight 99.97 g), the best growth performance was found in the 31.69% dietary protein group. In addition, the mRNA expression levels of GH, IGF1, S6K1 and 4EBP1 increased with the increase in dietary protein levels up to 31.69%, then gradually declined. In Stage 4 (initial weight 302.82 g), dietary protein levels did not affect the growth performance. Based on the quadratic regression analysis of the SGR, the optimal dietary protein level of each stage was estimated to be 33.08% (Spring, Stage 1), 26.45% (Summer, Stage 2), 33.06% (Autumn, Stage 3) and 26.45% (Winter, Stage 4) of dry diet. [ABSTRACT FROM AUTHOR]

In strongly magnetized astrophysical plasma systems, magnetic reconnection is believed to be the primary process during which explosive energy release and particle acceleration occur, leading to significant high-energy emission. Past years have witnessed active development of kinetic modeling of relativistic magnetic reconnection, supporting this magnetically dominated scenario. A much less explored issue in studies of relativistic reconnection is the consequence of three-dimensional dynamics, where turbulent structures are naturally generated as various types of instabilities develop. This paper presents a series of three-dimensional, fully kinetic simulations of relativistic turbulent magnetic reconnection (RTMR) in positronâ€"electron plasmas with system domains much larger than kinetic scales. Our simulations start from a force-free current sheet with several different modes of long-wavelength magnetic field perturbations, which drive additional turbulence in the reconnection region. Because of this, the current layer breaks up and the reconnection region quickly evolves into a turbulent layer filled with coherent structures such as flux ropes and current sheets. We find that plasma dynamics in RTMR is vastly different from its 2D counterpart in many aspects. The flux ropes evolve rapidly after their generation, and can be completely disrupted by the secondary kink instability. This turbulent evolution leads to superdiffusive behavior of magnetic field lines as seen in MHD studies of turbulent reconnection. Meanwhile, nonthermal particle acceleration and the timescale for energy release can be very fast and do not depend strongly on the turbulence amplitude. The main acceleration mechanism is a Fermi-like acceleration process supported by the motional electric field, whereas the nonideal electric field acceleration plays a subdominant role. We also discuss possible observational implications of three-dimensional RTMR in high-energy astrophysics. [ABSTRACT FROM AUTHOR]