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The effect of surface roughness on the interfacial contact resistance (ICR) and the corrosion behavior of 446 stainless steel in simulated anode environments for proton exchange membrane fuel cell (PEMFC) (i.e., 0.5 mol L−1 H2SO4 + 2 ppm F− and 5 × 10−4 mol L−1 H2SO4 + 0.1 ppm F− bubbled with hydrogen gas at 80 °C) was investigated by means of atomic force microscopy, potentiodynamic polarization, electrochemical impedance spectroscopy and ICR test. The surface roughness (Ra) produced by mechanical grinding increases noticeably with the decrease of sandpaper grit size from 1000# to 240#. 446 stainless steel shows the active state under free corrosion conditions in the two test solutions and the passive state at the typical anode working potential of PEMFC after the activation-passivation transition. The corrosion resistance decreases with the increase of roughness in both solutions. The corrosion product films formed in the solution with lower acidity are more protective, leading to the appearance of the diffusion process. The enlargement of surface roughness results in the gradual reduction of ICR, but the acceleration of active and passive dissolutions. [ABSTRACT FROM AUTHOR]

The computation offloading problem in mobile edge computing (MEC) has received a lot of attention, but service caching is also a research topic that cannot be ignored in MEC. Due to the limited resources available on the Edge Server (ES), a wise computation offloading and service caching policy must be formulated in order to maximize system offload efficiency. In this paper, a many-objective joint optimization computation offloading and service caching model (MaJOCOSC) is designed. The model takes into account the limited computing and storage resources of ES, the delay and energy consumption constraints of different types of tasks, and multiple processing modes of user tasks, and sets delay, energy consumption, task hit service rate, service cache balancing, and load balancing as the five optimization objectives of MaJOCOSC. Meanwhile, a non-dominated sorting genetic algorithm (NSGAIII-ASF&WD) based on achievement scalar function (ASF) and the k-nearest neighbor weighted distance mating selection strategy is proposed for better solving the model. The ASF ensures that the given strategy performs well for each objective value, and the k-nearest neighbor weighted distance provides the user with a diversity of strategies. Simulation results show that NSGAIII-ASF&WD can obtain better objective values when solving the model compared with other many-objective evolutionary algorithms, and a suitable computation offloading and service caching strategy is obtained. [ABSTRACT FROM AUTHOR]

Background: Acute monocytic leukemia-M5 (AML-M5) remains a challenging disease due to its high morbidity and poor prognosis. In addition to the evidence mentioned earlier, several studies have shown that programmed cell death (PCD) serves a critical function in treatment of AML-M5. However, the role and relationship between ferroptosis and necroptosis in AML-M5 remains unclear. Methods: THP-1 cells were mainly treated with Erastin and IMP-366. The changes of ferroptosis and necroptosis levels were detected by CCK-8, western blot, quantitative real-time PCR, and electron microscopy. Flow cytometry was applied to detect the ROS and lipid ROS levels. MDA, 4-HNE, GSH and GSSG were assessed by ELISA kits. Intracellular distribution of FSP1 was studied by immunofluorescent staining and western blot. Results: The addition of the myristoylation inhibitor IMP-366 to erastin-treated acute monocytic leukemia cell line THP-1 cell not only resulted in greater susceptibility to ferroptosis characterized by lipid peroxidation, glutathione (GSH) depletion and mitochondrial shrinkage, as the FSP1 position on membrane was inhibited, but also increased p-RIPK1 and p-MLKL protein expression, as well as a decrease in caspase-8 expression, and triggered the characteristic necroptosis phenomena, including cytoplasmic translucency, mitochondrial swelling, membranous fractures by FSP1 migration into the nucleus via binding importin α2. It is interesting to note that ferroptosis inhibitor fer-1 reversed necroptosis. Conclusion: We demonstrated that inhibition of myristoylation by IMP-366 is capable of switching ferroptosis and ferroptosis-dependent necroptosis in THP-1 cells. In these findings, FSP1-mediated ferroptosis and necroptosis are described as alternative mechanisms of PCD of THP-1 cells, providing potential therapeutic strategies and targets for AML-M5. [ABSTRACT FROM AUTHOR]

Herein, we have developed a novel single-molecular probe (NORP) for selective and accurate determination of NTR in living cells. It was discovered that up-regulation of endogenous NTR occurred in response to hypoxic stimulation, and there was a dependence between the NTR levels and the degree of hypoxia. [ABSTRACT FROM AUTHOR]

The initial corrosion resistance of ferritic stainless steels with various Cr and Mo levels in simulated fuel cell environments is evaluated using the HKD calculation method and electrochemical tests. HKD utilizes high-throughput DFT, KMC, and AIMD statistical coverage calculations to study passivation film development and ion/molecule adsorption behaviors, like O2-, F-, H 2 O, and OH-. Super-high Cr-containing Mo steel shows reliable corrosion resistance due to their stable structure and effective passivation film integrity at various F- concentrations and pH values. Furthermore, the impact of F- competes with O2-, influencing film formation as pH lowers and concentration rises. • The corrosion properties of ferritic stainless steel in the PEMFC environment. • HKD integrates high-throughput DFT, KMC, and AIMD. • The high-throughput DFT and KMC are applied to tailor the unit cell of stainless steel. • AIMD calculations provide passivation properties and elemental distribution in PEMFC environment. • The experiments confirm that SHCr-Mo maintains excellent corrosion resistance under PEMFC conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Innovating and proposing the DPWSIR model based on the DPSIR model. • Clarifying the toughness index for each stage of the DPWSIR model. • Using the G1-entropy weighting method to assign weights to evaluation indicators. • Analyzing the correlation between the criteria stage and the indicator stage indicators. • Providing support for improving the social-ecological resilience of arid cities in northwest China. Assessment of social-ecological system resilience is a reliable means of characterizing the system's ability to respond and recover in response to crisis events. This study takes Northwest China as the research area and aims to assess the spatiotemporal evolutionary trends of social-ecological system resilience levels. Driving force-Pressure-Meteorological constraint-State-Impact-Response(DPWSIR) model is proposed to construct the social-ecological system resilience evaluation system innovatively. The G1 entropy weight method is used to determine the index weight, and the comprehensive index method is used to calculate the social-ecological system resilience level values, evaluate the resilience of arid cities social-ecological systems in Northwest China from 2015 to 2021, and determine the resilience grades. The results demonstrate that: (1) The core status of regional central cities is highlighted, in general, the "center-periphery" spatial structure characteristics gradually stabilize. The resilience levels of regional central cities, such as Hohhot, Baotou, Xi'an, Lanzhou, Xining, Yinchuan, and Urumqi, are as high as 0.37, 0.43, 0.414, 0.41, 0.43, 0.58, and 0.39, respectively. (2) In the study area, the meteorological constraint resilience index showed a "flat-to-sudden decline" trend, with the inflection point of the sharp decline occurring in 2020. The decline in the resilience index value in arid cities is caused by the increase in precipitation and temperature, which is manifested as the result of "warming and humidification". (3) Meteorological factors, as the direct influencing factors of sandstorms, are the most critical to the assessment of the resilience of arid cities social-ecological systems. The relative percentage difference (RPD) is used to characterize the relative difference between the traditional model (DPSIR) and the improved model (DPWSIR). In areas for example Jinchang(29%), which is close to the dust sources and greatly affected by sandstorms, the differences in the social-ecological systems resilience are large and the RPD values are significant. Therefore, the DPWSIR model is more suitable for arid cities. This study provides scientific reference for the formulation of ecological environment protection policies and resilience improvement strategies for cities affected by sandstorms. [ABSTRACT FROM AUTHOR]