21 research outputs found

    Bifurcation of pulsation instability in one-dimensional H2−O2 detonation with detailed reaction mechanism

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    Classical modes of one-dimensional (1D) detonation characterized by a simplified reaction model are reproduced by using a real chemical kinetics for the H2−O2 system with argon dilution. As Ar dilution is varied, the bifurcation points of pulsating instability are identified and a formed bifurcation diagram is compared with that obtained by the one-step reaction model. Eventually, the numerical results demonstrate that, for real detonations with detailed chemistry, the criterion of Ng et al. works well on prediction of the 1D detonation instability. Furthermore, the detonability limits are found respectively at low and high Ar dilutions. Above the high Ar dilution limit, detonations decays to the minimum level where long autoignition time and small heat release rate make reestablishment impossible for both 1D and 2D simulations. However, below the low Ar dilution limit, a 1D detonation cannot be sustained due to high instability, while the corresponding cellular detonation can propagate sustainably due to the role of transverse instability

    Dielectric relaxation, resonance and scaling behaviors in Sr3Co2Fe24O41 hexaferrite

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    The dielectric properties of Z-type hexaferrite Sr(3)Co(2)Fe(24)O(41) (SCFO) have been investigated as a function of temperature from 153 to 503 K between 1 and 2 GHz. The dielectric responses of SCFO are found to be frequency dependent and thermally activated. The relaxation-type dielectric behavior is observed to be dominating in the low frequency region and resonance-type dielectric behavior is found to be dominating above 10(8) Hz. This frequency dependence of dielectric behavior is explained by the damped harmonic oscillator model with temperature dependent coefficients. The imaginary part of impedance (Z″) and modulus (M″) spectra show that there is a distribution of relaxation times. The scaling behaviors of Z″ and M″ spectra further suggest that the distribution of relaxation times is temperature independent at low frequencies. The dielectric loss spectra at different temperatures have not shown a scaling behavior above 10(8) Hz. A comparison between the Z″ and the M″ spectra indicates that the short-range charges motion dominates at low temperatures and the long-range charges motion dominates at high temperatures. The above results indicate that the dielectric dispersion mechanism in SCFO is temperature independent at low frequencies and temperature dependent at high frequencies due to the domination of resonance behavior

    Emerging mechanisms progress of colorectal cancer liver metastasis

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    Colorectal cancer (CRC) is the third most common malignancy and the second most common cause of cancer-related mortality worldwide. A total of 20% of CRC patients present with distant metastasis. The hepatic portal venous system, responsible for collecting most intestinal blood, makes the liver the most common site of CRC metastasis. The formation of liver metastases from colorectal cancer is a long and complex process. It involves the maintenance of primary tumors, vasculature invasion, distant colonization, and metastasis formation. In this review, we serve on how the CRC cells acquire stemness, invade the vascular, and colonize the liver. In addition, we highlight how the resident cells of the liver and immune cells interact with CRC cells. We also discuss the current immunotherapy approaches and challenges we face, and finally, we look forward to finding new therapeutic targets based on novel sequencing technologies

    Exploring the pathogenesis and immune infiltration in dilated cardiomyopathy complicated with atrial fibrillation by bioinformatics analysis

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    BackgroundAtrial fibrillation (AF) is a serious complication of dilated cardiomyopathy (DCM), which increases the risk of thromboembolic events and sudden death in DCM patients. However, the common mechanism of DCM combined with AF remains unclear. This study aims to explore the molecular mechanism and analyze immune infiltration in DCM complicated with AF through comprehensive bioinformatics analysis.MethodsThe gene expression datasets of DCM (GSE141910) and AF (GSE41177 and GSE79768) were obtained from the Gene Expression Omnibus database. Gene enrichment analyses were performed after screening the common differentially expressed genes (DEGs) of DCM and AF. Protein-protein interaction network was constructed in the STRING database and visualized in Cytoscape software, which helped to further screen the central functional modules of DEGs and hub genes. In addition, ImmuCellAI algorithm was performed to estimate immune infiltration patterns, and Spearman correlation was conducted to investigate the correlation between the abundance of multiple immune cells and the expression levels of hub immune-related genes after obtaining hub immune-related genes from the ImmPort database. The hub immune-related genes expression and immune infiltration patterns were additionally verified in the validation datasets (GSE57338, GSE115574, and GSE31821). The diagnostic effectiveness of hub immune-related genes was evaluated through Receiver Operator Characteristic Curve analysis.ResultsA total of 184 common DEGs in DCM and AF were identified for subsequent analyses. The functions of hub genes were significantly associated with immune responses. We identified 7 hub immune-related genes (HLA-DRA, LCK, ITK, CD48, CD247, CD3D, and IL2RG) and a spectrum of immune cell subsets including Monocyte, Neutrophil, and follicular helper T (Tfh) cells were found to be concurrently dysregulated in both DCM and AF. 7 hub immune-related genes were predominantly favorably correlated with Tfh cells and were primarily negatively correlated with Neutrophil infiltrations in DCM and AF. CD48+CD3D were verified to diagnose DCM and AF with excellent sensitivity and specificity, showing favorable diagnostic value.ConclusionsOur study reveals that immune cells (Tfh cells) disorders caused by hub immune-related genes (CD48 and CD3D) may be the common pathogenesis of DCM combined with AF, which lays a foundation for further immune mechanism research

    Perspectives on Immunotherapy of Metastatic Colorectal Cancer

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    Colorectal cancer, especially liver metastasis, is still a challenge worldwide. Traditional treatment such as surgery, chemotherapy and radiotherapy have been difficult to be further advanced. We need to develop new treatment methods to further improve the poor prognosis of these patients. The emergence of immunotherapy has brought light to mCRC patients, especially those with dMMR. Based on several large trials, some drugs (pembrolizumab, nivolumab) have been approved by US Food and Drug Administration to treat the patients diagnosed with dMMR tumors. However, immunotherapy has reached a bottleneck for other MSS tumors, with low response rate and poor PFS and OS. Therefore, more clinical trials are underway toward mCRC patients, especially those with MSS. This review is intended to summarize the existing clinical trials to illustrate the development of immunotherapy in mCRC patients, and to provide a new thinking for the direction and experimental design of immunotherapy in the future

    Optimal allocation of photovoltaic generations in buildings‐to‐distribution‐network integration system using improved backtracking search optimization algorithm

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    Abstract A novel optimal allocation framework for photovoltaic generations in an integration system of buildings‐to‐distribution‐network using improved backtracking search optimization algorithm is proposed here. In the proposed framework, photovoltaic generations are optimally allocated to optimize the overall performance of a buildings‐to‐distribution‐network regarding the efficient active power usage of photovoltaic generations, the energy savings, and voltage profile improvement of distribution network. The effects of building active demand response on the photovoltaic generations' optimal allocation are considered in the proposed framework. An improved backtracking search algorithm using two new operators is developed to optimize the active power reduction factors and locations of photovoltaic generations. The test results of IEEE 33‐bus and 69‐bus systems demonstrate that the developed framework can take full advantage of photovoltaic generation power and the active demand response of buildings to coordinate the efficient active power usage of photovoltaic generations, the voltage profile improvement and energy savings of a buildings‐to‐distribution‐network. In addition, the improved backtracking search optimization algorithm converges faster than genetic algorithm, classical backtracking search optimization algorithm, and bird swarm algorithm

    A Novel Three-Dimensional Vector Analysis of Axial Globe Position in Thyroid Eye Disease

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    Purpose. To define a three-dimensional (3D) vector method to describe the axial globe position in thyroid eye disease (TED). Methods. CT data from 59 patients with TED were collected and 3D images were reconstructed. A reference coordinate system was established, and the coordinates of the corneal apex and the eyeball center were calculated to obtain the globe vector EC→. The measurement reliability was evaluated. The parameters of EC→ were analyzed and compared with the results of two-dimensional (2D) CT measurement, Hertel exophthalmometry, and strabismus tests. Results. The reliability of EC→ measurement was excellent. The difference between EC→ and 2D CT measurement was significant (p=0.003), and EC→ was more consistent with Hertel exophthalmometry than with 2D CT measurement (p<0.001). There was no significant difference between EC→ and Hirschberg test, and a strong correlation was found between EC→ and synoptophore test. When one eye had a larger deviation angle than its fellow, its corneal apex shifted in the corresponding direction, but the shift of the eyeball center was not significant. The parameters of EC→ were almost perfectly consistent with the geometrical equation. Conclusions. The establishment of a 3D globe vector is feasible and reliable, and it could provide more information in the axial globe position

    Orosomucoid 1 promotes colorectal cancer progression and liver metastasis by affecting PI3K/AKT pathway and inducing macrophage M2 polarization

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    Abstract Approximately 25–30% of those affected by colorectal cancer (CRC), the most prevalent gastrointestinal malignancy, develop metastases. The survival rate of patients with liver metastasis of CRC (CRLM) remains low owing to its unpredictability and a lack of biomarkers that can be applied to distinguish groups at higher risk for CRLM among patients with CRC. Therefore, our study aimed to find biomarkers that can predict the risk of CRLM. Screening of the Gene Expression Omnibus database, supported by an analysis of clinically obtained tissue and serum data using qPCR and ELISA, in an attempt to identify relevant biomarkers, enabled us to determine that orosomucoid 1 (ORM1) was differentially expressed in liver metastases and primary tumors of patients with CRC. Functionally, overexpression of ORM1 promoted the epithelial-mesenchymal transition and the proliferative, migratory, and invasive activities of MC38 cells and activated the PI3K/AKT signaling pathway. Moreover, MC38 cells overexpressing ORM1 enhanced the tumor immune microenvironment by promoting macrophage M2 polarization and elevating interleukin-10 (IL-10) expression. In vivo experiments further confirmed in vitro results, indicating that liver metastases elevated by ORM1 were partially attenuated by the depletion of macrophages or IL-10. Considered together, ORM1 promotes CRC progression and liver metastasis by regulating tumor cell growth and inducing macrophage M2 polarization, which mediates tumor immune tolerance, and thus acts as a potential predictive marker and therapeutic target in CRLM

    Effect of crevice density on biological soil crust development on rock cut slope in mountainous regions, Sichuan, China

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    Abstract Background The rock cut slope (RCS) could cause damage to regional ecological functions and landscapes and requires recovery. Biological soil crusts (BSCs) are pioneer and dominant colonizers during the initial recovery stage. To accelerate the natural recovery of RCS, the development process and influencing agents of BSC should be revealed. Thus, the area index of crevices (I R), BSC coverage (COV) and biomass (BM), soil weight (SW), and major soil nutrients [organic carbon (OC), total nitrogen (TN) and total phosphorus (TP)] content, collected from 164 quadrats on 13 RCSs in the mountainous area of west Sichuan Province, China, were measured, to explore the effect of crevice of RCS on BSC development. Results Soil OC, TN and TP on RCSs ranged from 18.61 to 123.03 g kg−1, 0.96 to 6.02 g kg−1 and 0.52 to 2.46 g kg−1, respectively, and were approximately to or higher than those on natural slopes. The OC, TN and TP contents in soils elevated unsystematically with recovery time of RCSs. BSCs on RCS distributed along crevices generally and firstly. During the first 13 years of natural recovery, COV, BM and SW ranged from 6.5 to 28.2%, 14.43 to 67.25 g m−2, and 127.69 to 1277.74 g m−2, respectively. COV, BM and SW increased linearly with I R on RCSs. The positive correlation between COV and BM and I R was insignificantly impacted by bedrock, slope aspect and altitude within the recovery time less than 13 years. COV and BM on RCSs increased significantly when the recovery time is more than 27 years. Conclusions Crevice on RCSs could be a major environmental factor which is conducive to BSC development and soil accumulation through creating a space for water and soil particle. Furthermore, with the increase of recovery time of RCSs, BSCs may grow and reach a stable state with the promotion of soil nutrients, plant growth and microbial activity. These results provide a development process of BSC that from inside to outside the crevices on RCSs. In the areas with stable rock strata and a low risk of geological disasters, purposeful improvement in crevice density on RCS may effectively accelerate BSC development
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