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The influence of the ablation velocity Va on the evolution of single-mode ablative Rayleigh–Taylor instability from the linear to the deeply nonlinear phases is investigated via two-dimensional numerical simulations. Linear growth rates from simulations agree well with the asymptotic theory except for larger discrepancies in the intermediate Froude number regime. The weakly nonlinear growth behavior of the bubble amplitude is found dependent on a critical perturbation wavenumber in a broad Froude number regime. For a linearly stable mode, its nonlinear excitation threshold is higher for larger Va and thus harder to be exceeded. For short-wavelength modes taking significant ablation effects, the bubble penetration velocity is found to reaccelerate after the first saturation and eventually saturate at a larger value with larger Va, due to stronger vortex-acceleration effects and more significant increase in g. [ABSTRACT FROM AUTHOR]

Ensuring stable water quality standards in drinking water source reservoirs plays a decisive role in ensuring water safety. In this study, a series of indicators such as secchi disk transparency (SD), permanganate index (CODMn), total phosphorus (TP), total nitrogen (TN), ammonia nitrogen (NH3-N) and Chlorophyll.a (Chl.a) were used to detect and characterize the water quality of Shanxi Reservoir in Wenzhou, China. And explore the water quality change points by combining the Water Pollution Index (WPI), Mann-Kendall test and rescaled extreme difference analysis. The results show that the overall water quality of Shanxi Reservoir is excellent and can safely perform its watershed function. The water quality pollution index value in the reservoir area showed an increasing trend, with an overall value range of 0.34-0.94. The water quality was monitored in the process of organic pollution, phosphorus and NH3-N with a significant trend of improvement. Future trends in water quality indicate that water quality in the reservoir will not deteriorate. Change points for SD, Chl.a, TN and CODMn occur in May 2019, December 2019, December 2018 and May 2021, NH3 -N and TP have no water quality change points throughout the monitoring process. It is recommended to avoid nitrogen pollution in water bodies to prevent harming water ecological safety. [ABSTRACT FROM AUTHOR]

The two-plasmon-decay instability (TPD) in the large-incidence-angle regime is studied via fluid and particle-in-cell (PIC) simulations. It is found that the TPD threshold in this regime within a narrow incidence angle range close to 60∘ can be orders of magnitude lower than the normal-incidence threshold. A threshold formula is proposed for this regime and is verified by fluid and PIC simulations. PIC simulations show significant laser absorption and energetic electron generation once TPD is excited. The incident angle and the laser spot size have a significant influence on the TPD in the large-incidence-angle regime. The low threshold and significant hot electron generation in this regime pose potentially unexpected preheating risks to inertial confinement fusion. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the protective effect of dexmedetomidine (Dex) against renal injury in diabetic nephropathy (DN) rats by inhibiting the nuclear factor-κB (NF-κB) pathway. MATERIALS AND METHODS: A total of 36 Sprague-Dawley rats were randomly divided into three groups, including: normal group (n=12), model group (n=12) and Dex group (n=12). The rats underwent no treatment in normal group. In model group, the diabetes model was successfully established, and normal saline was intraperitoneally injected after operation. In Dex group, the diabetes model was established as well, and Dex was intraperitoneally injected after operation. After intervention for 2 weeks, the samples were taken for use. Blood urea nitrogen (BUN) and serum creatinine (Cr) were detected using a full-automatic biochemical analyzer. The expression of Caspase-3 was detected via immunohistochemistry. Western blotting was conducted to detect the protein expression of NF-κB. The apoptosis was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. In addition, the levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were determined via enzyme-linked immunosorbent assay (ELISA). RESULTS: The levels of BUN and Cr were significantly higher in model group and Dex group than those in normal group (p<0.05). However, they were significantly lower in Dex group than those in the model group (p<0.05). Immunohistochemistry results showed that the mean optical density of Caspase-3 positive expression increase remarkably in model group and Dex group when compared with normal group (p<0.05). However, it significantly declined in Dex group when compared with the model group (p<0.05). The results of Western blotting revealed that model group and Dex group exhibited evidently higher relative protein expression of NF-κB than normal group (p<0.05). However, Dex group displayed notably lower relative protein expression of NF-κB than model group (p<0.05). TUNEL assay demonstrated that the apoptosis rate increased significantly in the model group and Dex group when compared with normal group (p<0.05). However, it remarkably declined in Dex group in comparison with the model group (p<0.05). Finally, ELISA assay indicated that model group and Dex group had markedly higher levels of IL-6 and TNF-α than normal group (p<0.05). However, the levels of IL-6 and TNF-α were significantly lower in Dex group than model group (p<0.05). CONCLUSIONS: Dex inhibits inflammation and apoptosis by suppressing the NF-κB signaling pathway, thereby exerting a protective effect against renal injury in DN rats. [ABSTRACT FROM AUTHOR]

The coupling and evolution of two-mode ablative Rayleigh-Taylor instability (ARTI) in two-dimensional geometry are studied via numerical simulations. We focus primarily on two scenarios: Coupling and bubble competition of a long and a short wavelength mode and of two short-wavelength modes. It is found that the long-wavelength modes tend to dominate in the nonlinear phase of the long-short coupling cases. The presence of the short-wavelength mode in the long-short cases enhances the total ARTI bubble vertex velocity. However, due to the formation of enclosed bubbles, this enhancement does not increase monotonically with the initial short-wavelength amplitude. Coupling of two short-wavelength modes forms a long-wavelength component which grows faster than each individual short-wavelength mode. [ABSTRACT FROM AUTHOR]

Summary: Gas diffusion layer (GDL) plays an important role in the performance of membrane electrode assembly (MEA) in polymer electrolyte fuel cells. In this work, 2‐type MEAs were prepared by 2 different GDLs of 29  BC and 29‐WUT, and the performance were investigated using polarization curve methods. The performance of MEA with 29‐WUT was 120 mV higher than 29  BC at 1600 mA/cm2. Electrochemical impedance spectroscopy (EIS) was applied to measure the mass transport resistance of 2‐type MEAs under normal running condition. The results of EIS showed that the mass transport resistance of 29  BC was 3.15 times higher than that of 29‐WUT at 1600 mA/cm2. To clarify this phenomenon, limiting current methods were applied under diluting oxygen concentration, low humidity, and high flow rate conditions. The results of limiting current methods showed that both the total oxygen transport resistance and the molecular diffusion resistance in the GDL of 29  BC were larger than that of 29‐WUT due to the lower porosity of gas diffusion substrate in 29  BC. As a result, EIS can be well combined with limiting current methods to analyze oxygen transport resistance in GDLs of fuel cells. [ABSTRACT FROM AUTHOR]

Hepatitis B virus ( HBV) infection is one of the major causes of chronic liver inflammation. Tim-3 acts as a negative regulatory molecule and plays a critical role in immune tolerance. In the current study, we investigated Tim-3 expression on peripheral monocytes and CD3+ CD16/ CD56+ natural killer like T ( NKT-like) cells in chronic hepatitis B ( CHB) patients. Peripheral blood mononuclear cells (PBMCs) were isolated from 52 CHB patients and 60 healthy controls. Tim-3+ CD14+ cells and Tim-3+ CD3+ CD16/ CD56+ cells were analyzed by flow cytometry. Results showed that expression of Tim-3 was significantly increased on both the monocytes and NKT-like cells in CHB patients than in controls ( P = 0.002 and P < 0.001, respectively). Tim-3 levels on monocytes and NKT-like cells were further upregulated in patients with acute-on-chronic liver failure ( ACLF). In addition, we assessed the correlation of Tim-3 expression with levels of alanine aminotransferase ( ALT) and tumor necrosis factor alpha ( TNF-α). Data revealed that Tim-3 expression on both monocytes and NKT-like cells was positively correlated with level of ALT ( r = 0.59, P < 0.001, and r = 0.60, P < 0.001, respectively), whereas Tim-3 expression on NKT-like cells was negatively correlated with serum level of TNF-α ( r = −0.54, P < 0.001) in CHB patients. Our results suggest that Tim-3 may play important roles in the pathogenesis of CHB. [ABSTRACT FROM AUTHOR]

An analysis for the linear stability of fiber suspensions in the Taylor–Couette flow is conducted. The orientation state of fibers is determined using the linear, quadratic and composite HL-I closure model and the model of the fiber contribution to the total stress is established based on the slender-body theory. The linear stability equation is derived and solved with the Chebyshev spectral method. The results show that the suppression effect is most predominant for the composite HL-I model, while least predominant for the linear closure model. The longer fibers and suspensions with high volume fraction have a more predominant influence on suppressing the instability. The contribution of the suspending fluid to the change rate of the disturbance energy dominates the energy dissipation. While the contribution of the fiber shear stress increases monotonously with increasing fiber aspect ratio for the three closure models, the contribution based on the composite HL-I closure model is the largest, and that based on the linear closure model is the smallest. The effect of fiber aspect ratio on the change rate of the disturbance energy caused by the fiber shear stress is more predominant than that of the fiber volume fraction. The positive energy caused by the fiber shear stress consumes the gross energy of the fluid system and leads to a suppression of the flow instability. [ABSTRACT FROM AUTHOR]

An electron crystallographic image-processing technique based on the combination of high-resolution electron microscopy and electron diffraction has been developed to investigate the commensurate structural modulation in the high-T, superconductor (Pb[sub0.5]Sr[sub0.3]Cu[sub0.2])Sr[sub2](Ca[sub0.6]Sr[sub0.4])Cu[sub2]O[suby]. After symmetry averaging, a structure image was obtained by image deconvolution at the resolution limited by that of the electron microscope. Then phase extension was employed to enhance the image resolution up to about 1.25 A by means of the electron diffraction data corrected with an empirical method. In the final projected potential map. the occupational and/or positional modulation is clearly observed for all atoms, including oxygen. The key points of determining superstructures by the technique are studied and discussed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the risk factors for the short-term outcome of patients with hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF), and to establish a risk model for predicting the short-term outcome of these patients., Methods: A total of 338 patients with HBV-related ACLF who were admitted to 30 Lod hospital of PLA hospital from January 2010 to January 2014 were enrolled, and a prospective clinical follow-up was performed for them. Multivariate logistic regression was used to determine the risk factors for short-term (12 weeks) outcome, the predictive model with logistic regression equation was established, and the predictive value of this model was evaluated., Results: The multivariate logistic regression analysis showed that age, a family history of hepatitis B, hepatic encephalopathy (HE), hepatorenal syndrome (HRS), white blood cell (WBC), platelet (PLT), international normalized ratio (INR), total bilirubin (TBil), total bile acid (TBA), creatinine, Na, HBV DNA, and HBeAg were the independent risk factors for the short-term outcome of these patients. Logistic(p) = -4.466 + 1.192 age + 1.631 family history of hepatitis B + 1.091 HE + 1.631 HRS + 1.208 WBC -1.487 PLT + 1.092 INR + 1.446 TBil + 1.608 TBA -1.101 CHE + 1.279 CRE -1.713 Na + 1.032 HBV DNA + 0.833 HBeAg. The area under the receiver operating characteristic curve of the model for the prediction of short-term outcome was 0.930, the cut-off value was 3.16, the sensitivity was 0.860, and the specificity was 0.871. With the increasing scores of the equation, the mortality of patients tended to increase gradually., Conclusion: Age, a family history of hepatitis B, HE, HRS, WBC, PLT, INR, TBil, TBA, CHE, CRE, Na, HBV DNA, and HBeAg are the independent risk factors for the short-term outcome of patients with HBV-related ACLF. The model for predicting short-term outcome established on the basis of independent risk factors has a better clinical value in guiding clinical therapy.

In order to study the role of afferent renal nerves in 2K2C Goldblatt hypertension, the renal afferent nerves were selectively lesioned by bilateral T9-L2 spinal dorsal rhizotomy before clipping (internal diameter, 0.3 mm) of birenal arteries. Systolic blood pressure of the rat was measured by tail-cuff method. Concentrations of catecholamines, Ang II, and aldosterone were determined respectively by HPLC-EC and RIA, and vascular structural changes were measured by blood vessel micro-image analysis system coupled with a computer. The results showed that the concentrations of NE and E in medulla oblongata, adrenal gland and plasma, and of plasma Ang II and aldosterone as well as body weight of the rat were all significantly increased. The heart coefficient (heart wt/body wt), the media thickness, and the media thickness/lumen diameter in superior mesenteric arteries were also increased in 2K2C hypertensive rats (clipping, 6 wk) as compared with those in control rats. Bilateral rhizotomy delayed development of 2K2C hypertension and prevented above-mentioned vascular structural changes, the NE and E concentrations of medulla oblongata, adrenal gland and plasma were all decreased, hypothalamic NE and E were increased, and plasma Ang II level was not significantly changed. These results suggest that afferent renal nerves may play a partial role in the development of hypertension in 2K2C rats by activating sympathetic nervous system as a result of affecting metabolic activities of brain catecholaminergic neurons, and that high-plasma Ang II and aldosterone as well as heart hypertrophy and proliferation of vascular smooth muscle cells may also participate in the pathogenesis of hypertension in 2K2C rats.