The art of abstraction reflects the rich imagination of human beings to a certain extent and is now widely used in movies, games, advertisements, and other modern design fields. In this paper, a new ...edge tangential flow algorithm applicable to image abstraction is proposed, which first estimates the gradient strength and gradient direction of each point in a given input image by using the Sobel operator and then establishes the edge graph of the input image by using the edge information transfer strategy. On this basis, the application and value of abstract art and this graphical abstract processing method in modern graphic design are discussed, and the essence of abstract form art is perfectly embodied so as to make the two perfectly integrated. The results show that in the application of graphic abstract processing in graphic design, the average value of user attraction, understanding, and memory dimension scores are 0.53, 0.675, and 0.683, respectively, which verifies the effectiveness of this graphic design practice through users.
Development of anion exchange membranes with good dimension, chemical stability, high conductivity and long life-time simultaneously is still a challenge for practical application of anion exchange ...membrane fuel cells. Herein, a mechanically and chemically stable poly(styrene-b-(ethylene-co-butylene)-b-styrene) triblock copolymer based crosslinked membranes are designed, prepared and characterized. N,N,N′,N′-tetramethyl-1,6-hexanediamine is introduced into the membranes as the crosslinker and functional reagent, which exhibits the significant improvement in water uptake (less than 7%), swelling ratio (8–5%, greatly smaller than uncrosslinked membranes) and tensile strength (higher than 18MPa). The hydroxide conductivity (14.9mScm−1 at 30°C) of the obtained membrane is obtained due to hydrophilic/hydrophobic microphase separation formed between the structure of crosslinking and quaternary ammonium groups. It demonstrates that incorporating stable crosslinking structure to polymer backbone greatly improves the chemical stability under Fenton and alkaline long-term tests. Furthermore, the peak power density of an H2/O2 single fuel cells reaches high peak power density of 416mWcm−2 at 0.514V. Based on these outstanding properties, the developed crosslinked membranes will be a promising candidate material for anion exchange membrane fuel cells.
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•The crosslinked triblock SEBS based AEMs were prepared with a facile method.•TMHDA was used as both crosslinker and functional reagent.•The AEMs show good dimension stability and low swelling ratio.•The crosslinked AEMs exhibit good oxidative stability and alkaline stability.•A peak power density of 416mWcm−2 was obtained in AEMFC.
Platinum dispersity on the carbon support is first shown as a factor of local oxygen transport resistance in this work, while its impact on PEMFC performance is also analyzed. The dispersity of ...platinum is defined as the distribution density of Pt particles on the surface of carbon supports. In order to exclude the influence of catalyst layer thickness, different platinum dispersity cathode catalyst layers are prepared by mechanical mixing Pt/C with different mass ratios, different Pt loadings with the same amount of Pt and carbon in the MEAs to keep the thickness of catalyst layers consistent. Initial fuel cell performance is much higher with lower Pt dispersity. Oxygen transport resistance is measured through limiting current density method, and the total oxygen transport resistance Rtotal, Fick diffusion resistance RF, and local oxygen transport resistance R are calculated. All of them increase at higher Pt dispersity. Platinum dispersity shows obvious influence both on performance and oxygen transport resistance. Thus, increasing the ratio of platinum particles distributed at the surface of carbon supports and the density of platinum particles on carbon supports can be effective ways to solve the problem of performance loss with low Pt loading at high current densities.
•Explore an important factor of local oxygen transport resistance – Pt dispersity.•Investigate the influence of Pt dispersity on MEA performance.•Verify the great influence of water film on local oxygen transport resistance.
Alkaline anion exchange membrane fuel cells (AEMFCs) are attracting more and more attention due to the advantages of using non-platinum-group (NPG) metal catalysts and less expensive metal hardware ...at the high pH conditions. However, the studies of electrodes with the non-precious metal are still less and the performance of the AEMFC operated with the NPG metal catalysts need to improve. In this work, based on AEMFCs operated with the commercial non-precious metal ORR catalysts (Acta 4020), a two dimensional, two-phase flow and steady-state agglomerates model is developed, and the effects of operational conditions of the relative humidity and the structure of the catalyst layer on fuel cell performance are numerically studied and analyzed. The results demonstrate that the relative humidity directly impacts the water distribution and transport in the MEA, and the low relative humidity in the cathode can increase the water back diffusion from the anode to the cathode and improve the fuel cell performance. An increase in the catalyst loading has been found to have a positive effects on the fuel cell performance, but the improvement is limited when the catalyst loading increases to a certain value. In addition, the increase in the mass ratio of catalyst to ionomer results in a decrease in the thickness of the ionomer film, but the excessive mass ratio of the catalyst to the ionomer also leads to a decrease in ionic conductivity, thereby deteriorating the performance of fuel cell. At last, operating with the optimized conditions from the model, the AEMFC realized a good fuel cell performance, and the peak power density reached 566 mW cm−2 and 326 mW cm−2 for H2/O2 and H2/Air (CO2-free) at 60 °C, respectively, and the results are higher than those reported in references.
•An agglomerate model for AEMFC operated with non-noble metal catalyst is developed.•The effects of RHs on the water distribution and transport are analyzed in details.•The cell performance with non-noble metal catalyst reached 566 mW cm−2 at 60 °C.
Background
Interleukin-6 (IL-6) has been demonstrated to be a critical factor for breast cancer malignancy. However, the molecular mechanisms by which IL-6 induce breast cancer cells ...epithelial–mesenchymal-transition (EMT) and stemness remain elusive.
Methods
Breast cancer cell lines T47D and MCF7 were exposed to IL-6, the expression of PIM1 was examined by quantitative real-time PCR (qRT-PCR) and western blot. Luciferase reporter assay was used to determine the transcriptional modulation of PIM1 by IL-6 and STAT3 inhibitor. Transwell assay was used to detect the invading ability of breast cancer cells induced by IL-6 or PIM1. The expressions of EMT and stemness markers were determined by qRT-PCR.
Results
IL-6 promoted PIM1 expression in a dose- and time-dependent manner, and this induction could be abrogated by inhibiting STAT3 activation, subsequently suppressing the transcriptional level of PIM1. Moreover, we noticed that knocking down of PIM1 in cells which was exposed to IL-6 significantly impaired the invasion ability and the expression of EMT and stemness markers. On the contrary, overexpression of PIM1 promoted cell invasion and upregulated the expression of EMT and stemness markers. In addition, we demonstrated that c-myc, the cofactor of PIM1, involved in the pro-oncogenic roles of PIM1. Knocking down of c-myc attenuated the PIM1-induced cell EMT and stemness.
Conclusion
This study proposed the upregulation of PIM1 by IL-6 contributed to breast cancer cell aggressiveness and targeting PIM1 or c-myc could be novel approaches for breast cancer treatment.
The anion exchange ionomer incorporated into the electrodes of an anion exchange membrane fuel cell (AEMFC) enhances anion transport in the catalyst layer of the electrode, and thus improves ...performance and durability of the AEMFC. In this work, a novel ionomer based on a triblock copolymer with high conductivity and good durability is synthesized successfully. The spectroscopy (such as
1
H-NMR, FT-IR) results of the ionomer indicate that the functional group is grafted onto the poly(styrene-ethylene/butylene-styrene) (SEBS) successfully and the OH
−
conductivity of the ionomer is 30 mS cm
−1
at 75 °C. Besides, quaternary ammonium SEBS (QASEBS) is used as the ionomer in a H
2
/O
2
AEMFC and exhibits a significant durability of 500 h at a constant current density of 100 mA cm
−2
, moreover, the degradation rate of voltage is only 0.22 mV h
−1
during the 500 h durability test. In addition, the peak power density of the membrane electrode assembly (MEA) with the QASEBS ionomer reaches 375 mW cm
−2
at 50 °C, which is 3 times than that of the MEA using the commercially available Acta I2 ionomer (124 mW cm
−2
) for comparison.
The anion exchange ionomer incorporated into the electrodes of an anion exchange membrane fuel cell (AEMFC) enhances anion transport in the catalyst layer of the electrode, and thus improves performance and durability of the AEMFC.
Novel N1, C4, C5-substituted imidazolium-based crosslinked anion exchange membranes (AEMs) are prepared by the incorporation of polybenzimidazole (PBI) into the poly(vinylbenzyl chloride) (PVBC) ...matrix. 1-Butyl-4,5-dimethyl-imidazole (BDIm) with methyl substituents at C4, C5 and long side alkyl substituents at N1 is firstly synthesized to enhance the stability of AEMs by steric hindrance and hyperconjugative effects and characterized by
1
H NMR. The effects of crosslinking density of AEMs on the hydroxide conductivity, swelling ratio, thermal stability, oxidative and alkaline stability are evaluated in detail for fuel cell applications. The results reveal that the crosslinking structure between PVBC and PBI plays a vital role in achieving both good mechanical properties and low swelling ratio. Notably, the AEM containing 66.7% PVBC has the highest ionic conductivity of 16.1 mS cm
−1
at 20 °C with an IEC of 2.1 mmol g
−1
. Meanwhile, the AEMs also exhibit excellent oxidative stability in Fenton's reagent for 200 h and alkaline stability in 1 mol L
−1
KOH at 60 °C for 480 h. Furthermore, the peak power density of an H
2
/O
2
single fuel cell is up to 54 mW cm
−2
.
Novel N1, C4, C5-substituted imidazolium-based crosslinked anion exchange membranes (AEMs) are prepared by the incorporation of polybenzimidazole (PBI) into the poly(vinylbenzyl chloride) (PVBC) matrix.
Background
Mitoxantrone hydrochloride injection for tracing (MHI), a new strategy to identify lymph nodes, has not been tested for axillary node staging in breast cancer. This multicenter, ...self-controlled, non-inferiority trial aimed to evaluate MHI’s efficacy and safety in sentinel lymph node biopsy (SLNB).
Methods
The trial was conducted across seven hospitals from December 2019 to December 2020. Patients with early-stage breast cancer received MHI and technetium-99m (99mTc) during the surgery. Sentinel node detection rates were compared between MHI and 99mTc to evaluate non-inferiority and concordance. Non-inferiority was valid if the lower limit of the 95% CI of sentinel node relative detection rate difference was ≥−5%.
Results
SLN relative detection rate of MHI was 97.31% (362/372). Of the SLNs, 79.69% (871/1093) were co-detected by both tracers. Of the patients, 4.13% (16/387) had adverse events and recovered during the follow-up.
Conclusions
MHI is a lymphatic tracer with comparable efficacy to radionuclides and can be used alone or in combination with radioactive substances for SLNB.
Clinical Trial Registration
http://www.chinadrugtrials.org.cn
, CTR20192435.
Water management has been proven significant for enhancing both performance and durability of anion exchange membrane fuel cell. Besides searching new material, decreasing membrane thickness and ...modifying operation parameters, a simple and universal method of altering membrane structure is proposed in this work. Composite membranes made by unique processing method that includes both casting and electrospinning processes were compared with traditional casting membrane, all with the same thickness of 40 µm. Comparing to traditional casting membrane, the composite membrane put at proper position shows a higher water permeability, thus even more than 50% enhancement of the peak performance.
The anion exchange membranes (AEMs) with both high ionic conductivity and good stability is always the research focus role for the long-term use of AEM fuel cells. A series of the mechanically and ...chemically stable PVBC/PBI crosslinked membranes, functionalized with N1-butyl substituted BDABCO groups, were designed, prepared and characterized. With the crosslinking by polybenzimidazole (PBI), the membranes showed good flexibility, strength and low swelling ratio (less than 18%). N1-butyl substituted doubly-charged BDABCO was introduced in the AEMs during the crosslinking reaction instead of the traditional dipping method, benefiting from the improvement compatibility between polymers and BDABCO groups. Attributing to the well-developed phase separation between hydrophilic domains and hydrophobic domains, the family of synthesized AEMs exhibited the higher conductivities than that of DABCO based membranes, which was proved by TEM and SAXS. The M-BDABCO-OH-1:3 with high BDABCO content displayed the highest ionic conductivity of 29.3 and 91.4mScm−1 at 20 and 80°C, respectively. The results of alkaline stability showed that the membranes had the superior chemical stability after immersing in a 1molL−1 KOH at 60°C solution for more than 550h. Furthermore, the peak power density of an H2/O2 single fuel cell using the optimized M-BDABCO-OH-1:3 was up to 340mWcm−2 at 0.492V with the EIS consisting of membrane resistance less than 0.1Ωcm2 which was much smaller than the other AEMs. Overall, the developed membranes demonstrated the superior performance and would be a promising candidate material for AEMFCs.
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•N1-butyl substituted doubly-charged BDABCO was introduced in AEMs.•The crosslinked AEMs with BDABCO were prepared with a facile method.•The conductivity of AEMs reached 91.4mScm−1 at 80°C with microphase separation.•The crosslinked AEMs exhibit good oxidative stability and alkaline stability.•A peak power density of 340mWcm−2 was obtained in AEMFC.
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