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To simulate the creep characteristics of corn straw particles under uniaxial compression, a 6-level 2D model was created using PFC 2D software according to the actual uniaxial creep test, the grain size, and shape of corn straw particles. Five groups of controlled tests were designed by the control variable method to study the influence of Maxwell body parameters Em, m; Kelvin body parameters Ek, k; and friction coefficient f on the creep curve of Burgers model. Results revealed that the creep characteristics of corn straw are affected by these 5 parameters. After multiple debugging by trial-and-error method, simulation parameters suitable for describing the creep characteristics of corn straw particles were obtained. The creep curves obtained by simulation under these parameters are consistent with those obtained by physical tests. It was shown that PFC software can not only study the creep characteristics of geotechnical materials, but also study the creep characteristics of agricultural fiber materials, which provides a reference for the subsequent rheological characteristics of biomass materials. [ABSTRACT FROM AUTHOR]

We develop a general equilibrium model with heterogeneous firms and foreign direct investment cost uncertainty and investigate the survival of foreign-owned firms. The survival probabilities of foreign-owned firms depend on firm-level characteristics, such as productivity, and host country characteristics, such as market size. We show that a foreign-owned firm will be less likely to be shut down when its parent firm's productivity is higher and its indigenous competitors are less productive. Although a larger market size will always reduce the survival probability of indigenous firms, it can lead to a higher survival probability for foreign-owned firms if their parent firms are sufficiently productive. [ABSTRACT FROM AUTHOR]

In order to explore the conveying mechanism of kneaded corn stalk in the screw conveyor and improve the conveying performance of the screw conveyor, the study of the screw conveying process of kneaded corn stalk was carried out, and the simulation model of the screw conveying process was established by using the discrete element method. The results showed that: The pitch, feed amount and screw shaft speed have significant effects on the productivity and power of screw conveying, and there are significant interactions. The optimal parameters of the multi-factor simulation optimization test were 319.428 mm pitch, feed amount of 71.062 kg/min, screw shaft speed of 117.034 r/min, corresponding productivity of 71.517 kg/min and power of 769.84 W. This study reveals the screw conveying mechanism of kneaded corn stalk, verifies the feasibility of using discrete element simulation to analyse the conveying process of kneaded corn stalk, and provides a theoretical basis for improving and optimizing the screw conveying device. [ABSTRACT FROM AUTHOR]

Exposure to fungi can result in a wide range of comorbidities depending on the immune status of the host. Chronic exposure and reactivity to fungi such as Aspergillus fumigatus can result in conditions such as severe asthma with fungal sensitization (SAFS) or allergic bronchopulmonary aspergillosis (ABPA). However, the pathophysiology of SAFS and ABPA is not well understood. Here, we report that the chitinase-like protein YKL-40 is elevated in lung lavage fluid from humans with asthma that are sensitized to fungi. Initial studies demonstrated that mice deficient in the murine ortholog of YKL-40, breast regression protein-39 (BRP-39, chitinase-3-like 1, Chi3l1), were not more susceptible to acute infection with A. fumigatus. However, in an experimental model of fungal-associated allergic airway inflammation (fungal asthma), Chi3l1–/– mice had significantly increased airway hyperresponsiveness (AHR). Surprisingly, increased AHR in Chi3l1–/– mice occurred in the presence of significantly lower type 2 responses (decreased eosinophil numbers and decreased IL-4, IL-5, IL-33, CCL17, and CCL22 levels), although type 1 and type 17 responses were not different. Increased AHR was not associated with differences in periodic acid-Schiff staining of lung tissue, differences in the expression of Muc5ac and Clca3, nor differences in lung edema. Bone marrow chimera studies revealed that the presence of BRP-39 in either the hematopoietic or nonhematopoietic compartment was sufficient for controlling AHR during fungal asthma. Collectively, these results indicate that BRP-39 protects against AHR during fungal asthma despite contributing to type 2 inflammation, thus highlighting an unexpected protective role for BRP-39 in allergic fungal asthma. [ABSTRACT FROM AUTHOR]

Machine learning techniques have been widely used in transient stability prediction of power systems. When using the post-fault dynamic responses, it is difficult to draw a definite conclusion about how long the duration of response data used should be in order to balance the accuracy and speed. Besides, previous studies have the problem of lacking consideration for the confidence level. To solve these problems, a hierarchical method for transient stability prediction based on the confidence of ensemble classifier using multiple support vector machines (SVMs) is proposed. Firstly, multiple datasets are generated by bootstrap sampling, then features are randomly picked up to compress the datasets. Secondly, the confidence indices are defined and multiple SVMs are built based on these generated datasets. By synthesizing the probabilistic outputs of multiple SVMs, the prediction results and confidence of the ensemble classifier will be obtained. Finally, different ensemble classifiers with different response times are built to construct different layers of the proposed hierarchical scheme. The simulation results show that the proposed hierarchical method can balance the accuracy and rapidity of the transient stability prediction. Moreover, the hierarchical method can reduce the misjudgments of unstable instances and cooperate with the time domain simulation to insure the security and stability of power systems. [ABSTRACT FROM AUTHOR]

Pax5/B cell lineage specific activator protein (BSAP) is a B lineage-specific regulator that controls the B lineage-specific gene expression program and immunoglobulin gene VH to DJH recombination. Despite extensive studies on its multiple functions, little is known about how the activity of Pax5 is regulated. Here, we show that co-expression of histone acetyltransferase E1A binding protein p300 dramatically enhances Pax5-mediated transcriptional activation. The p300-mediated enhancement is dependent on its intrinsic histone acetyltransferase activity. Moreover, p300 interacts with the C terminus of Pax5 and acetylates multiple lysine residues within the paired box DNA binding domain of Pax5. Mutations of lysine residues 67 and 87/89 to alanine within Pax5 abolish p300-mediated enhancement of Pax5-induced Luc-CD19 reporter expression in HEK293 cells and prevent Pax5 to activate endogenous Cd19 and Blnk expression in Pax5-/- murine pro B cells. These results uncover a novel level of regulation of Pax5 function by p300-mediated acetylation. [ABSTRACT FROM AUTHOR]

The soluble ectodomain of fibroblast growth factor receptor-IIIc (sFGFR2c) is able to bind to fibroblast growth factor (FGF) ligands and block the activation of the FGF-signaling pathway. In this study, sFGFR2c inhibited lung fibrosis dramatically in vitro and in vivo. The upregulation of α-smooth muscle actin (α-SMA) in fibroblasts by transforming growth factor-β1 (TGF-β1) is an important step in the process of lung fibrosis, in which FGF-2, released by TGF-β1, is involved. sFGFR2c inhibited α-SMA induction by TGF-β1 via both the extracellular signal-regulated kinase 1/2 (ERK1/2) and Smad3 pathways in primary mouse lung fibroblasts and the proliferation of mouse lung fibroblasts. In a mouse model of bleomycin (BLM)-induced lung fibrosis, mice were treated with sFGFR2c from d 3 or d 10 to 31 after BLM administration. Then we used hematoxylin and eosin staining, Masson staining and immunohistochemical staining to evaluate the inhibitory effects of sFGFR2c on lung fibrosis. The treatment with sFGFR2c resulted in significant attenuation of the lung fibrosis score and collagen deposition. The expression levels of α-SMA, p-FGFRs, p-ERK1/2 and p-Smad3 in the lungs of sFGFR2c-treated mice were markedly lower. sFGFR2c may have potential for the treatment of lung fibrosis as an FGF-2 antagonist.