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Numerical experiments using the WRF model were conducted to analyze the sensitivity of Typhoon Mangkhut intensification simulations to seven widely used planetary boundary layer (PBL) parameterization schemes, including YSU, MYJ, QNSE, MYNN2, MYNN3, ACM2, and BouLac. The results showed that all simulations generally reproduced the tropical cyclone (TC) track and intensity, with YSU, QNSE, and BouLac schemes better capturing intensification processes and closely matching observed TC intensity. In terms of surface layer parameterization, the QNSE scheme produced the highest Ck/Cd ratio, resulting in stronger TC intensity based on Emanuel’s potential intensity theory. In terms of PBL parameterization, the YSU and BouLac schemes, with the same revised MM5 surface layer scheme, simulated weaker turbulent diffusivity Km and shallower mixing height, leading to stronger TC intensity. During the intensification period, the BouLac, YSU, and QNSE PBL schemes exhibited stronger tangential wind, radial inflow within the boundary layer, and updraft around the eye wall, consistent with TC intensity results. Both PBL and surface layer parameterization significantly influenced simulated TC intensity. The QNSE scheme, with the largest Ck/Cd ratio, and the YSU and BouLac schemes, with weaker turbulent diffusivity, generated stronger radial inflow, updraft, and warm core structures, contributing to higher storm intensity. 

The question of at what resolution the large eddy simulations (LESs) of a tropical cyclone (TC) high wind area may converge largely remains unanswered. To address this issue, LESs with five resolutions of 300 m, 100 m, 60 m, 33 m, and 20 m are performed in this study to simulate a high wind area near the radius of maximum wind of Typhoon Chanthu (2021) using the Weather Research and Forecasting (WRF) model. The results show that, for a limited area LES, model grid resolution may alter the local turbulence structure to generate significantly different extreme values of temperature, moisture, and winds, but it only has a marginal impact on the median values of these variables throughout the vertical column. All simulations are able to capture the turbulent roll vortices in the TC boundary layer, but the structure and intensity of the rolls vary substantially in different resolution simulations. Local hectometer-scale eddies with vertical velocities exceeding 10 m s−1 are only observed in the 20 m resolution simulation but not in the coarser resolution simulations. The ratio of the resolved turbulent momentum fluxes and turbulent kinetic energies (TKEs) to the total momentum fluxes and TKEs appears to show some convergence of LESs when the grid resolution reaches 100 m or finer, suggesting that it is an acceptable grid resolution for LES applications in TC simulations. 

Abstract AimsWe have shown that human cardiac muscle patches (hCMPs) containing three different types of cardiac cells—cardiomyocytes (CMs), smooth muscle cells (SMCs), and endothelial cells (ECs), all of which were differentiated from human pluripotent stem cells (hPSCs)—significantly improved cardiac function, infarct size, and hypertrophy in a pig model of myocardial infarction (MI). However, hPSC-derived CMs (hPSC-CMs) are phenotypically immature, which may lead to arrhythmogenic concerns; thus, since hPSC-derived cardiac fibroblasts (hPSC-CFs) appear to enhance the maturity of hPSC-CMs, we compared hCMPs containing hPSC-CMs, -SMCs, -ECs, and -CFs (4TCC-hCMPs) with a second hCMP construct that lacked hPSC-CFs but was otherwise identical [hCMP containing hPSC-CMs, -AECs, and -SMCs (3TCC-hCMPs)]. Methods and resultshCMPs were generated in a fibrin scaffold. MI was induced in severe combined immunodeficiency (SCID) mice through permanent coronary artery (left anterior descending) ligation, followed by treatment with cardiac muscle patches. Animal groups included: MI heart treated with 3TCC-hCMP; with 4TCC-hCMP; MI heart treated with no patch (MI group) and sham group. Cardiac function was evaluated using echocardiography, and cell engraftment rate and infarct size were evaluated histologically at 4 weeks after patch transplantation. The results from experiments in cultured hCMPs demonstrate that the inclusion of cardiac fibroblast in 4TCC-hCMPs had (i) better organized sarcomeres; (ii) abundant structural, metabolic, and ion-channel markers of CM maturation; and (iii) greater conduction velocities (31 ± 3.23 cm/s, P < 0.005) and action-potential durations (APD50 = 365 ms ± 2.649, P < 0.0001; APD = 408 ms ± 2.757, P < 0.0001) than those (velocity and APD time) in 3TCC-hCMPs. Furthermore, 4TCC-hCMPs transplantation resulted in better cardiac function [ejection fraction (EF) = 49.18% ± 0.86, P < 0.05], reduced infarct size (22.72% ± 0.98, P < 0.05), and better engraftment (15.99% ± 1.56, P < 0.05) when compared with 3TCC-hCMPs (EF = 41.55 ± 0.92%, infarct size = 39.23 ± 4.28%, and engraftment = 8.56 ± 1.79%, respectively). ConclusionCollectively, these observations suggest that the inclusion of hPSC-CFs during hCMP manufacture promotes hPSC-CM maturation and increases the potency of implanted hCMPs for improving cardiac recovery in mice model of MI. 

Abstract Extreme temperature conditions seriously impair male reproductive development in plants; however, the molecular mechanisms underlying the response of anthers to extreme temperatures remain poorly described. The transcription factor phytochrome-interacting factor4 (PIF4) acts as a hub that integrates multiple signaling pathways to regulate thermosensory growth and architectural adaptation in plants. Here, we report that SlPIF4 in tomato (Solanum lycopersicum) plays a pivotal role in regulating cold tolerance in anthers. CRISPR (clustered regularly interspaced short palindromic repeats)–associated nuclease Cas9-generated SlPIF4 knockout mutants showed enhanced cold tolerance in pollen due to reduced temperature sensitivity of the tapetum, while overexpressing SlPIF4 conferred pollen abortion by delaying tapetal programmed cell death (PCD). SlPIF4 directly interacts with SlDYT1, a direct upstream regulator of SlTDF1, both of which (SlDYT1 and SlTDF1) play important roles in regulating tapetum development and tapetal PCD. Moderately low temperature (MLT) promotes the transcriptional activation of SlTDF1 by the SlPIF4–SlDYT1 complex, resulting in pollen abortion, while knocking out SlPIF4 blocked the MLT-induced activation of SlTDF1. Furthermore, SlPIF4 directly binds to the canonical E-box sequence in the SlDYT1 promoter. Collectively, these findings suggest that SlPIF4 negatively regulates cold tolerance in anthers by directly interacting with the tapetal regulatory module in a temperature-dependent manner. Our results shed light on the molecular mechanisms underlying the adaptation of anthers to low temperatures. 

ABSTRACT Azoarcus sp. strain DD4 can cometabolically degrade 1,4-dioxane and 1,1-dichloroethylene (1,1-DCE) when grown with propane and other substrates. The complete genome sequence of strain DD4 reveals a diverse collection of bacterial monooxygenase genes that may contribute to its versatility in degrading commingled groundwater pollutants.