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The phase field approach to fracture is efficient in simulating crack nucleation and propagation but requires a very fine mesh to resolve the regularization length scale. To alleviate such difficulty we have developed a variational h-adaption method for this approach based on Mosler and Ortiz (Int J Numer Methods Eng 72(5):505–523, 2007, Int J Numer Methods Eng 77(3):437–450, 2009), which consists of a mesh refinement scheme based on edge bisection and a mesh coarsening scheme via node deletion. The main advantages are that a single criterion can be used for the adaption process without any undetermined constant as in a residual-based method and that there is no need to weigh the importance of the two coupled fields, as would be needed for a recovery-based method. We showed examples to demonstrate the efficiency of the proposed method and compared the performance of two bisection operations: simple edge bisection and the modified backward longest edge propagation path scheme. In particular, these two methods lead to condition numbers of the coefficient matrices on the same order of magnitude.

Autophagy plays vital roles in the interaction between the necrotrophic fungal pathogen Sclerotinia sclerotiorum and its hosts. However, so far, only little is known about the impacts of autophagy machinery in S. sclerotiorum per se on the fungal morphogenesis and pathogenesis. Here, through functional genomic approaches, we showed that SsATG8, one of the core components of the autophagy machinery, and its interactor SsNBR1, an autophagy cargo receptor, are important for vegetative growth, sclerotial formation, oxalic acid (OA) production, compound appressoria development, and virulence of S. sclerotiorum. Complementation assays with chimeric fusion constructs revealed that both LDS [AIM (ATG8 interacting motif) / LIR (LC3-interacting region) docking site] and UDS [UIM (ubiquitin-interacting motif) docking site] sites of the SsATG8 are required for its functions in autophagy and pathogenesis. Importantly, ΔSsatg8 and ΔSsnbr1 mutants showed enhanced sensitivity to the exogenous treatment with the proteasome inhibitors bortezomib and carfilzomib, and ΔSsnbr1 mutant had decreased expression of SsATG8 under the proteasomal stress conditions, suggesting that a cross-talk exists between ubiquitin–proteasome and selective autophagy pathways, which enables downstream protein degradation to proceed properly during diverse biological processes. Collectively, our data indicate that SsATG8- and SsNBR1-mediated autophagy is crucial for S. sclerotiorum development, proteasomal stress response and virulence.

© 2020 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ We present a phase field model to simulate brittle fracture in an initially straight Euler–Bernoulli beam, with generalization to curved beams. We start from formulating the problem with the principle of minimum potential energy in a 3D solid, with the displacement field and the phase field as primary arguments. We then select, for each cross section, representative fields that characterize the said cross section, including the beam deflection and rotation, and two independent ansatz variables within the cross section to represent the phase field. The problem then reduces to a minimization with only one-dimensional field variables. A feature of the proposed method is, without discretizing the phase field within the cross section, it can represent its variation within the cross section, allowing to simulate cracks partially going through the thickness due to bending as well as axial loads.

With the significant increasing water demand and the fossil-fuel cost, the wind-powered desalination technique has become more and more attractive for coastal area. It has experienced fast development and brought amount of benefits into our daily life, industry and agriculture. The main risks for the further penetration of such autonomous and decentralized desalination systems are the intermittent and fluctuating nature of the wind power resource. They can potentially result in a series of problems, including negative effects on the membrane performance, the component service duration, and complexity of the plant configuration, operation and control. To avoid or alleviate these effects, the efforts about solution strategies have been developed and mainly divided into three categories. The first category is the energy storage trying to maintain a constant operation condition for the RO unit. The energy storage carriers include batteries, supercapacitors, hydrogen, flywheel, pumped water, compressed air, and their combinations. The second category is the hybrid energy system. In a hybrid energy system, wind energy combined with other forms of energy such as solar PV, diesel, gravitational potential energy is employed as the energy supply. The third category is adjusting operating conditions of RO process and matching the RO capacity with transient energy supply, to make the process be adaptable with the wind power variation. Based on above summaries and analyses, this paper is aiming to be helpful for the design, operation and application of wind powered RO hereafter.

Bronchopulmonary dysplasia (BPD) is a significant global health problem and currently lacks effective therapy. We established a neonatal rat model of BPD to investigate therapeutic potential of bone marrow-derived mesenchymal stem cells (BMSCs) in neonatal hyperoxic lung injury.BMSCs were isolated, identified, and transfected by lentiviral vector carrying green fluorescent protein gene in vitro. Neonatal Sprague-Dawley rats were injected intravenously with either BMSCs or phosphate-buffered saline following 95% oxygen exposure, and assessed for the survival rate and alveolar injury during recovery.Treatment with BMSCs after oxygen exposure for 7 days improved survival of neonatal rat during recovery. BMSCs protected against neonatal rat hyperoxic lung injury during recovery as demonstrated by enhanced expression of AQP5 and SP-C, likely due to the suppression of alveolar cell apoptosis and lung inflammation responses to oxygen with up-regulation of the expression of BCL-2 gene and down-regulation of the expression of BAX gene and stimulation of vascular endothelial growth factor and so on.BMSCs protect against O2-mediated injury partially through stimulation of potent mediators that participate in tissue repair.

BPD is a significant global health problem and currently lacks effective therapy. We established a neonatal rat model of BPD to investigate therapeutic potential of BMSCs in neonatal lung disease. BMSCs were isolated, identified, and transfected by lentiviral vector carrying GFP gene in vitro. Neonatal rats were injected intravenously with either BMSCs or PBS after they had been already exposed to high oxygen for seven days, and assessed on post-injection day 3, day 7, and day 14 for weight gaining, lung histology, radical alveolar counts, and lung cytokine level. BMSCs were positive for CD29, CD44, and CD90 whereas negative for CD34, CD45, CD11b and with differentiation potential into osteoblasts, adipocytes, and chondrocytes. BMSCs ex- pressed GFP after transfected by lentivirus. After injection, BMSCs exert their therapeutic benefit of improving weight gaining, preventing alveolar growth arrest, and suppressing lung inflammation of neonatal rats. Intravenous delivery of BMSCs in newborn rats conferred pro- tection from hyperoxia-induced lung injury, and one of the effects of BMSCs treatment is suppressing lung inflammation.

BPD is a significant global health problem and currently lacks effective therapy. We established a neonatal rat model of BPD to investigate therapeutic potential of BMSCs in neonatal lung disease. BMSCs were isolated, identified, and transfected by lentiviral vector carrying GFP gene in vitro. Neonatal rats were injected intravenously with either BMSCs or PBS after they had been already exposed to high oxygen for seven days, and assessed on post-injection day 3, day 7, and day 14 for weight gaining, lung histology, radical alveolar counts, and lung cytokine level. BMSCs were positive for CD29, CD44, and CD90 whereas negative for CD34, CD45, CD11b and with differentiation potential into osteoblasts, adipocytes, and chondrocytes. BMSCs expressed GFP after transfected by lentivirus. After injection, BMSCs exert their therapeutic benefit of improving weight gaining, preventing alveolar growth arrest, and suppressing lung inflammation of neonatal rats. Intravenous delivery of BMSCs in newborn rats conferred protection from hyperoxia-induced lung injury, and one of the effects of BMSCs treatment is suppressing lung inflammation.

Background Embryonic stem (ES) cells have attracted significant attention from researchers around the world because of their ability to undergo indefinite self-renewal and produce derivatives from the three cell lineages, which has enormous value in research and clinical applications. Until now, many ES cell lines of different mammals have been established and studied. In addition, recently, AS-ES1 cells derived from Apodemus sylvaticus were established and identified by our laboratory as a new mammalian ES cell line. Hence further research, in the application of AS-ES1 cells, is warranted. Results Herein we report the generation of multiple mesodermal AS-ES1 lineages via embryoid body (EB) formation by the hanging drop method and the addition of particular reagents and factors for induction at the stage of EB attachment. The AS-ES1 cells generated separately in vitro included: adipocytes, osteoblasts, chondrocytes and cardiomyocytes. Histochemical staining, immunofluorescent staining and RT-PCR were carried out to confirm the formation of multiple mesodermal lineage cells. Conclusions The appropriate reagents and culture milieu used in mesodermal differentiation of mouse ES cells also guide the differentiation of in vitro AS-ES1 cells into distinct mesoderm-derived cells. This study provides a better understanding of the characteristics of AS-ES1 cells, a new species ES cell line and promotes the use of Apodemus ES cells as a complement to mouse ES cells in future studies.