Summary
Fuel cell vehicles face complicated road conditions, which may impact on the output performance of fuel cell stacks. In the present study, the water transport in the gas diffusion layer (GDL) ...of proton exchange membrane fuel cell (PEMFC) under vibration conditions are investigated. A stochastic method is employed to reconstruct the 3‐D GDL with experimentally validated varying porosities. The volume of fluid (VOF) method is adopted to investigate the two‐phase problems. Sinusoidal vibration source terms are superposed, which can vary with required amplitudes and directions. Over time, the water transport process takes three steps: water intrusion, water accumulation, and water removal. The water intrusion tends to start from the sides of the GDL, then spreads into the central area. Compared with the no‐vibration case, the water saturations are higher in both the vertical and horizontal vibration cases. The vibration will enhance the water transport through GDL layers. As such, the higher the vibration amplitude and frequency, the larger the water saturation. Accordingly, the water saturation of the GDL vary sinusoidally over time. The water breakthrough paths are identified and compared during the water removal processes. Vibration in the horizontal direction is much easier to promote the water transport inside a layer compared with vibration in the vertical direction. More substantial water saturation in the GDL layers will restrict the gas transfer paths. Consequently, less oxygen will participate in the reaction, which will further impact on the fuel cell performance.
In this study, the water transport in the GDL under vibration conditions are investigated in the present. The GDL with X‐ray tested varying porosities is reconstructed with a stochastic method and sinusoidal vibrations are superposed with required amplitudes and frequencies. The water removal steps are summarized, which include water intrusion, water accumulation, and water removal. The water breakthrough paths are identified and the vibration effects on the water transport are discussed.
Cirrhosis is a major risk factor for the development of hepatocellular carcinoma (HCC). Portal vein thrombosis is not uncommon after splenectomy in cirrhotic patients, and many such patients take ...oral anticoagulants including aspirin. However, the long-term impact of postoperative aspirin on cirrhotic patients after splenectomy remains unknown.
The main purpose of this study was to investigate the effect of postoperative long-term low-dose aspirin administration on the development of HCC and long-term survival of cirrhotic patients after splenectomy.
The clinical data of 264 adult patients with viral hepatitis-related cirrhosis who underwent splenectomy at the First Affiliated Hospital of Xi'an Jiaotong University from January 2000 to December 2014 were analyzed retrospectively. Among these patients, 59 who started taking 100 mg/d aspirin within seven days were enrolled in the aspirin group. The incidence of HCC and overall survival were analyzed.
During follow-up, 41 (15.53%) patients developed HCC and 37 (14.02%) died due to end-stage liver diseases or other serious complications. Postoperative long-term low-dose aspirin therapy reduced the incidence of HCC from 19.02% to 3.40% after splenectomy (log-rank test,
0.028). Univariate and multivariate analyses showed that not undertaking postoperative long-term low-dose aspirin therapy odds ratio (OR) = 6.211, 95% confidence interval (CI): 1.142-27.324,
0.016 was the only independent risk factor for the development of HCC. Similarly, patients in the aspirin group survived longer than those in the control group (log-rank test,
0.041). Univariate and multivariate analyses showed that the only factor that independently associated with improved overall survival was postoperative long-term low-dose aspirin therapy OR = 0.218, 95%CI: 0.049-0.960,
0.044.
In patients with viral hepatitis-related cirrhosis, long-term post-splenectomy administration of low-dose aspirin reduces the incidence of HCC and improves the long-term overall survival.
Objective. To explore the efficacy of Herb-partitioned moxibustion in treating IBS-D patients. Method. 210 IBS-D patients were randomly assigned on a 3:3:2 basis to group HM, group FM, or group PB ...for 4-week treatment. The change of GSRS total score at weeks 4 and 8, the changes of GSRS specific scores, and adverse events were evaluated. Results. Patients in group HM and group FM had lower GSRS total score at week 4 (1.98±0.303, 2.93±0.302 versus 3.73±0.449) and at week 8 (2.75±0.306, 3.56±0.329 versus 4.39±2.48) as compared with patients’ score in group PB. However, there was no significant difference of GSRS total score between group HM and group FM. The effect of HM was significantly greater than that of orally taking PB in ameliorating the symptoms of rugitus (0.38 versus 0.59, P<0.05), abdominal pain (0.28 versus 0.57, P<0.01), abdominal distension (0.4 versus 0.7, P<0.01), and increased passage of stools (0.06 versus 0.25, P<0.01) at the end of treatment period. In the follow-up period, patients’ therapeutic effect in group HM remained greater than that in group FM (in abdominal pain, abdominal distension, and increased passage of stools) and that in group PB (in loose stools). Conclusions. HM appears to be a promising, efficacious, and well-tolerated treatment for patients with IBS-D.
In this study, we examined the associations of the high-performance work system (HPWS) with employee innovative behavior, and tested a theoretical model in which these associations were mediated by ...employee voice (promotive and prohibitive voice) and moderated by psychological safety. Matched data were collected from 46 HR（Human Resource） managers and 374 full-time employees from 46 companies in China with multi-source and time-lagged techniques. We found that the HPWS is associated with employee behavior. Both the promotive voice and prohibitive voice partially mediate the relationship between HPWS and employee innovative behavior. Psychological safety moderates the relationship between HPWS and the promotive voice. However, psychological safety does not moderate the relationship between HPWS and the prohibitive voice. Furthermore, psychological safety moderates the mediation effect of the promotive voice between HPWS and employee innovative behavior. We discuss the theoretical and practical implications of these findings.
•Catalyst layers under various ingredient contents and structures are reconstructed.•A pore-scale model is developed to simulate the reactive transport processes.•High platinum/catalyst ratio can ...enhance the transport and improve the performance.•The active catalyst area should be given precedence during the electrode fabrication.•A novel catalyst layer design is proposed and can improve the performance by 50%.
A pore-scale model based on the lattice Boltzmann method (LBM) is developed to simulate the reactive transport processes in the cathode catalyst layer of a proton exchange membrane fuel cell (PEMFC). The porous structures of the cathode catalyst layers are reconstructed in the process-based method with the consideration of carbon supporter, platinum, ionomer and pores. Its characteristics are analyzed including pore size distribution, phase connectivity and active catalyst area. The effects of two critical parameters, platinum/catalyst (Pt/C) and ionomer/catalyst (I/C) ratios, and structure design are investigated in terms of oxygen concentration distribution, reactive area, and reaction rate. The results indicate that, under the constant platinum loading (0.3 mg cm−2), a higher Pt/C ratio yields a thinner catalyst layer, which significantly enhances the oxygen transport and improves the performance. For the same Pt/C ratio, although a higher I/C ratio brings more mass transport loss, it increases the active catalyst area and ultimately yields better performance. Therefore, the active catalyst area should be given precedence during catalyst layer fabrication. To realize a large active catalyst area on the premise of low transport loss, an ideal catalyst layer structure design is proposed and capable of improving the performance by 50%.
Objectives
To evaluate the effect of echinacoside (ECH) on cognitive dysfunction in post cerebral stroke model rats.
Methods
The post stroke cognitive impairment rat model was created by occlusion of ...the transient middle cerebral artery (MCAO). The rats were randomly divided into 3 groups by a random number table: the sham group (sham operation), the MCAO group (received operation for focal cerebral ischemia), and the ECH group (received operation for focal cerebral ischemia and ECH 50 mg/kg per day), with 6 rats in each group. The infarct volume and spatial learning were evaluated by triphenyl tetrazolium chloride staining and Morris water maze. The expression of α7nAChR in the hippocampus was detected by immunohistochemistry. The contents of acetylcholine (ACh), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), activities of choline acetyltransferase (ChAT), acetylcholinesterase (AChE), and catalase (CAT) were evaluated by enzyme linked immunosorbent assay. The neural apoptosis and autophagy were determined by TUNEL staining and LC3 staining, respectively.
Results
ECH significantly lessened the brain infarct volume and ameliorated neurological deficit in infarct volume and water content (both
P
<0.01). Compared with MCAO rats, administration of ECH revealed shorter escape latency and long retention time at 7, 14 and 28 days (all
P
<0.01), increased the α7nAChR protein expression, ACh content, and ChAT activity, and decreased AChE activity in MCAO rats (all
P
<0.01). ECH significantly decreased MDA content and increased the GSH content, SOD, and CAT activities compared with MCAO rats (all
P
<0.05). ECH suppressed neuronal apoptosis by reducing TUNEL-positive cells and also enhanced autophagy in MCAO rats (all
P
<0.01).
Conclusion
ECH treatment helped improve cognitive impairment by attenuating neurological damage and enhancing autophagy in MCAO rats.
BackgroundCCR8-expressing CD4 and Foxp3 positive Treg (CCR8+ Treg) has been demonstrated to be a major driver for immunosuppression in solid tumors1 Superscript. Clinical studies have shown that CCR8 ...is selectively up-regulated by tumor resident Tregs in several tumor types including clear cell renal cell carcinoma (ccRCC)2 Superscript and breast cancer3 Superscript. In these tumor types, CCR8 exhibit strong expression on tumor resident Tregs while it is rarely observed on Tregs in peripheral blood mononuclear cells (PBMCs). High expression of the CCR8 in tumor-infiltrating lymphocytes-Treg cells (TIL-Tregs) was associated with poor prognosis in breast cancer patients. These results suggest CCR8 as a promising therapeutic target; and anti-CCR8 mAbs could selectively inhibit a subpopulation of tumor resident Tregs in the tumor microenvironment (TME), to augment antitumor immunity.MethodsIn vitro assay:HBM1022 binding on human, cynomolgus CCR8 and TIL-Tregs are evaluated via flow cytometry. Blocking and ADCC functional assay are all based on CCR8 overexpressing cell lines.In vivo efficacy study:HBM1022 anti-CCR8 antibody was administered after implantation (≈ 100 mm3 Superscript tumor volume) alone and in combination with anti−PD-1.ResultsAnti-CCR8 antibody HBM1022 specifically binds to cell lines that over-express human or cynomolgus CCR8, as well as TIL-Tregs in multiple cancer types with the high affinity. HBM1022 potently blocks CCL1 binding to both human and cynomolgus CCR8. HBM1022 inhibits CCL1-induced migration and related GPCR signaling pathways. Furthermore, with enhanced antibody-dependent cell-mediated cytotoxicity (eADCC) activity, HBM1022 exhibits potent in vitro killing activity on CCR8-expressing cells. HBM1022 shows tumor growth inhibition as monotherapy in preclinical mouse syngeneic and humanized models. Moreover, HBM1022 shows enhanced antitumor activity with the combination of Keytruda® in preclinical efficacy models.ConclusionsOur finding reveals HBM1022 as an innovative immunotherapy targeting intra-tumoral suppressive Treg cells to change suppressive tumor to hot tumor. HBM1022 presents its great potential as exciting mono or combo anti-tumor therapies.ReferencesYiftah B, Gizi W, Eran L, et al. CCR8+FOXp3+ Treg cells as master drivers of immune regulation. Proc Natl Acad Sci U S A 2017;114 (23):6086–6091.Tetsuya Y, Yujiro K, Mitsunobu M, et al. Method of treating cancer with an anti-CCR8 having antibody-dependent cell-mediated cytotoxicity (ADCC) activity against cells expressing CCR8. US10550191B2. 2020.George P, Catherine K, Kenmin W, et al. Regulatory T cells exhibit distinct features in human breast cancer. Immunity 2016;45:1122–1134.
The ionic conductivity of anion exchange membranes (AEMs) directly determines the performance of anion exchange membrane fuel cells (AEMFCs), which highly depends on the hydration level of the ...membrane. A better understanding of the relationship between hydration level and membrane ionic conductivity is essential for membrane development and for water and thermal management analyses of AEMFCs. In this study, the effects of water activity and temperature on water uptake, equilibrium water content, and ionic conductivity of three high‐performance AEMs (Alkymer, Orion, and Pention) are quantitatively characterized via the designed experiments. The results show that Orion exhibits the lowest water uptake and highest ionic conductivity among the three membranes at high water activity and Alkymer exhibits good water‐retention capability and the highest ionic conductivity at low water activity. Empirical equations combining water activity and equilibrium water content are proposed based on fitted experimental data to define the hydration level. Empirical equations combining ionic conductivity, equilibrium water content, and temperature are fitted to illustrate the relationship between ionic conductivity and hydration level. The findings of this study can provide solid guidelines and support for the future experimental characterization and water and thermal management analyses of AEMFCs.
The effects of water activity and temperature on the water uptake, equilibrium water content, and ionic conductivity of three high‐performance AEMs are quantitatively characterized via the designed experiments. The findings of this study promise to make significant contributions to future work on the experimental characterization and water and thermal management analyses of AEMFCs.
Abstract Purpose To investigate the different miRNA expression profiles of postoperative radiotherapy sensitive and resistant patients of non-small cell lung cancer, explore their potential role and ...find some radio-sensitivity markers. Materials and methods Thirty non-small cell lung cancer patients who have been treated by postoperative radiotherapy were selected and were divided into radiotherapy sensitive group and resistant group according to overall survival and local or distant recurrence rate. Expression profile of miRNA in these two groups was detected by a microarray assay and the results were validated by quantitative RT-PCR and Northern blot. At the molecular level, the effect of one differently expressed miRNA (miR-126) on the growth and apoptosis of SK-MES-1 cells induced by irradiation was examined. Results Comparing with resistant patients, five miRNAs (miRNA-126, miRNA-let-7a, miRNA-495, miRNA-451 and miRNA-128b) were significantly upregulated and seven miRNAs (miRNA-130a, miRNA-106b, miRNA-19b, miRNA-22, miRNA-15b, miRNA-17-5p and miRNA-21) were greatly downregulated in radiotherapy sensitive group. Overexpression of miRNA-126 inhibited the growth of SK-MES-1 cells and promoted its apoptosis induced by irradiation. The expression level of p-Akt decreased in miRNA-126 overexpression group. After treating with phosphoinositidyl-3 kinase (PI3K) constitutively activator (IGF-1) and inhibitor (LY294002), miRNA-126 overexpression had no significant effects on the apoptosis of SK-MES-1 cells. Conclusion We found 12 differently expressed miRNAs in the radiotherapy sensitive and resistant non-small cell lung cancer samples. Moreover, our results showed miRNA-126 promoted non-small cell lung cancer cells apoptosis induced by irradiation through the PI3K-Akt pathway.
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