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The computational demands of 3D continuum models for proton exchange membrane fuel cells remain substantial. One prevalent approach is the hierarchical model combining a 2D/3D flow field with a 1D sub-model for the catalyst layers and membrane. However, existing studies often simplify the 1D domain to a linearized 0D lumped model, potentially resulting in significant errors at high loads. In this study, we present a computationally efficient neural network driven 3D+1D model for proton exchange membrane fuel cells. The 3D sub-model captures transport in the gas channels and gas diffusion layers and is coupled with a 1D electrochemical sub-model for microporous layers, membrane, and catalyst layers. To reduce computational intensity of the full 1D description, a neural network surrogates the 1D electrochemical sub-model for coupling with the 3D domain. Trained by model-generated large synthetic datasets, the neural network achieves root mean square errors of less than 0.2%. The model is validated against experimental results under various relative humidities. It is then employed to investigate the nonlinear distribution of internal states under different operating conditions. With the neural network operating at 0.5% of the computing cost of the 1D sub-model, the hybrid model preserves a detailed and nonlinear representation of the internal fuel cell states while maintaining computational costs comparable to conventional 3D+0D models. The presented hybrid data-driven and physical modeling framework offers high accuracy and computing speed across a broad spectrum of operating conditions, potentially aiding the rapid optimization of both the membrane electrode assembly and the gas channel geometry.

RiPP discovery has expanded the scope of post-translational modification chemistry, but genome mining of RiPP classes remains an unsolved challenge. Here, the authors employed bioinformatics and synthetic biology approaches to discover and characterize an unknown class of RiPPs, defined by an unusual amino-modified C-terminus.

Objective Pancreatic cancer is one of the leading causes of cancer-related deaths worldwide. Poor prognosis and low survival rates have driven the development of novel therapeutic strategies. Nanosecond pulsed electric field has emerged as a novel, minimal invasive and non-thermal treatment for solid tumors. It is of great significance to study the combination therapy of nsPEF and other treatment strategies for pancreatic cancer.Methods We developed neutrophil membrane-wrapped liposomal nanoparticles loaded with gemcitabine (NE/Lip-GEM) and investigated their use as a complementary agent for nsPEF treatment.Results Our results showed that neutrophil-mediated delivery of liposomal-gemcitabine (NE/Lip-GEM) efficiently inhibited the growth of pancreatic tumors in mice whose has been treated with incomplete nsPEF ablation.Conclusions The combination of nsPEF and NE/Lip-GEM may be a promising synergistic strategy for pancreatic cancer therapy.

Abstract Background Despite the widespread use of the single item self-rated health (SRH) question, its reliability has never been evaluated in Chinese population. Methods We used data from the China Health and Retirement Longitudinal Study, waves 1–4 (2011–2019). In wave 1, the same SRH question was asked twice, separated by other questions, on a subset of 4533 subjects, allowing us to examine the test–retest reliability of SRH. In addition, two versions of SRH questions (the WHO and US versions) were asked (n = 11,429). Kappa (κ), weighted kappa ( $${\kappa}_{w}$$ κ w ), and polychoric correlation coefficient (ρ) were used for reliability assessment. Cox proportional-hazards models were estimated to assess the predictive validity of SRH measurement for mortality over 7 years of follow up. To do so, relative index of inequality (RII) and slope index of inequality (SII) were estimated for each SRH scale. Results There was moderate to substantial test–retest reliability (κ = 0.54, $${\kappa}_{w}$$ κ w =0.63) of SRH; 31% of respondents who used the same scale twice changed their ratings after answering other questions. There was strong positive association between the two SRH measured by the two scales (ρ > 0.8). Compared with excellent/very good SRH, adjusted hazard ratios (HR) of death are 2.30 (95% CI, 1.70–3.13) for the US version and 1.86 (95% CI, 1.33–2.60) for the WHO version. Using slope indices of inequality, the WHO version estimated slightly larger mortality differences (RII = 3.50, SII = 15.53) than the US version (RII = 3.25, SII = 14.80). Conclusions In Chinese middle-aged and older population, the reliability of SRH is generally good, although the two commonly used versions of SRH scales could not be compared directly. Both indices predict mortality, with similar predictive validity.

Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor of the digestive tract. The most effective method of reducing the disease burden in areas with a high incidence of esophageal cancer is to prevent the disease from developing into invasive cancer through screening. Endoscopic screening is key for the early diagnosis and treatment of ESCC. However, due to the uneven professional level of endoscopists, there are still many missed cases because of failure to recognize lesions. In recent years, along with remarkable progress in medical imaging and video evaluation technology based on deep machine learning, the development of artificial intelligence (AI) is expected to provide new auxiliary methods of endoscopic diagnosis and the treatment of early ESCC. The convolution neural network (CNN) in the deep learning model extracts the key features of the input image data using continuous convolution layers and then classifies images through full-layer connections. The CNN is widely used in medical image classification, and greatly improves the accuracy of endoscopic image classification. This review focuses on the AI-assisted diagnosis of early ESCC and prediction of early ESCC invasion depth under multiple imaging modalities. The excellent image recognition ability of AI is suitable for the detection and diagnosis of ESCC and can reduce missed diagnoses and help endoscopists better complete endoscopic examinations. However, the selective bias used in the training dataset of the AI system affects its general utility.

The Global Navigation Satellite System Interferometric Reflectometry (GNSS-IR) technique provides a new remote sensing method that shows great potential for soil moisture detection and vegetation growth, as well as for climate research, water cycle management, and ecological environment monitoring. Considering that the land surface is always covered by vegetation, it is essential to take into account the impacts of vegetation growth when detecting soil moisture (SM). In this paper, based on the GNSS-IR technique, the SM was retrieved from multi-GNSS and multi-frequency data using a machine learning model, accounting for the impact of the vegetation moisture content (VMC). Both the signal-to-noise ratio (SNR) data that was used to retrieve SM and the multipath data that was used to eliminate the vegetation influence were collected from a standard geodetic GNSS station located in Nanjing, China. The normalized microwave reflectance index (NMRI) calculated by multipath data was mapped to a normalized difference vegetation index (NDVI), which was derived from Sentinel-2 data on the Google Earth Engine platform to estimate and eliminate the influence of VMC. Based on the characteristic parameters of amplitude and phase extracted from detrended SNR signals and NDVI derived from multipath data, three machine learning methods, including random forest (RF), multiple linear regression (MLR), and multivariate adaptive regression spline (MARS), were employed for data fusion. The results show that the vegetation effect can be well eliminated using the NMRI method. Comparing MLR and MARS, RF is more suitable for GNSS-IR SM inversion. Furthermore, the SM reversed from amplitude and phase fusion is better than only those from either amplitude fusion or phase fusion. The results prove the feasibility of the proposed method based on a multipath approach to characterize the vegetation effect, as well as the RF model to fuse multi-GNSS and multi-frequency data to retrieve SM with vegetation error-correcting.

Non-graphitic nitrogen-doped nano-scale diamonds were tested in the laboratory for their ability to activate peroxydisulfate for treating Microcystis-laden water. Flocculation was observed and up to 99.8% of the cyanobacterial cells were removed. The flocs’ composition showed that nano-scale diamonds with activated persulfate promoted the release of protein-like and humic-like substances during the treatment, which could have promoted agglomeration. Comprehensive analyses suggest that both radical and radical-free mechanisms were involved. Extracellular substances associated with the Microcystis cells were modified to function as active bioflocculants, leading to self-flocculation and sedimentation.

Abstract An accurate state of charge (SOC) estimation in battery management systems (BMS) is of crucial importance to guarantee the safe and effective operation of automotive batteries. However, the BMS consistently suffers from inaccuracy of SOC estimation. Herein, we propose a SOC estimation approach with both high accuracy and robustness based on an improved extended Kalman filter (IEKF). An equivalent circuit model is established, and the simulated annealing-particle swarm optimization (SA-PSO) algorithm is used for offline parameter identification. Furthermore, improvements have been made with noise adaptation, a fading filter and a linear-nonlinear filtering based on the traditional EKF method, and rigorous mathematical proof has been carried out accordingly. To deal with model mismatch, online parameter identification is achieved by a dual Kalman filter. Finally, various experiments are performed to validate the proposed IEKF. Experimental results show that the IEKF algorithm can reduce the error to 2.94% under dynamic stress test conditions, and robustness analysis is verified with noise interference, hence demonstrating its practicability for extending to state estimation of battery packs applied in real-world operating conditions.

In this study, nitrilotriacetic acid (NTA) was used to enhance UV/Fe0/H2O2 process for highly salty wastewater at neutral pH. The addition of Fe0 could not accelerate the UV/H2O2 process for salty wastewater treatment at neutral pH due to the precipitation of Fe ions. While NTA added into UV/Fe0/H2O2 process which could form complex with Fe ion, the tartrazine removal could increase from 45.7% to 84.7% within 60 ​min. The k-value of the UV/Fe0-NTA/H2O2 system to remove tartrazine is also 2.2 times higher than that in UV/Fe0/H2O2 system. Meanwhile, the UV/Fe0-NTA/H2O2 process could obtain good performance for salt wastewater treatment under a wide salt concentration level of 0–0.2 ​M. It can also expand the application range of pH to neutral pH. SEM and XPS characterization showed that the corrosion rate of Fe0 in salty system was faster, and the presence of NTA could accelerate the recirculation of Fe3+/Fe2+ on the Fe0 surface. EPR spectroscopic analysis and scavenge experiments showed that •OH was the main reactive radical for the removal of tartrazine in the UV/Fe0-NTA/H2O2 system. In addition, the k-value for removing tartrazine in various types of salt systems in the UV/Fe0-NTA/H2O2 system was 3.2–4.2 times that of the UV/Fe0/H2O2 system. It demonstrated UV/Fe0-NTA/H2O2 processes fits to different types of salt system. Therefore, this study will provide a new method for the treatment of saline wastewater at neutral pH.

Zero-valent iron/peroxymonosulfate (Fe0/PMS) has been considered as a promising approach for wastewater treatment. Anions and cations are widely present in wastewater and have significant effects on the performance of the Fe0/PMS system for wastewater treatment. Thus, in the present study, tartrazine was selected as the target model; SO42−, NO3−, HCO3−, and Cl− were selected as representative anions and Ca2+, Cu2+, Mg2+, and Mn2+ were chosen as representative cations. The effect of these anions and cations on tartrazine removal and major radicals in the Fe0/PMS were systematically investigated. The presence of a certain concentration of SO42− and Cl− had positive, NO3− had negative, and HCO3− had negligible effects on tartrazine removal in the Fe0/PMS system. SO42− and HCO3− had a small effect on the contribution proportion of reduction, SO4•− and •OH; a certain concentration of Cl− could enhance the contribution proportion of •OH; and NO3− would decrease the contribution proportion of SO4•− and •OH. A certain concentration of each of Ca2+, Cu2+, Mg2+, and Mn2+ could enhance the tartrazine removal in the Fe0/PMS system. Ca2+, Cu2+, and Mg2+ had no effect of the contribution of reduction, SO4•− and •OH, while a certain concentration of Mn2+ could enhance the contribution proportion of SO4•−. These results can provide some references for the Fe0/PMS system to treat actual wastewater containing anions and cations.

Spider silk is one of the hottest biomaterials researched currently, due to its excellent mechanical properties. This work reports a novel humidity sensing platform based on a spider silk-modified quartz tuning fork (SSM-QTF). Since spider silk is a kind of natural moisture-sensitive material, it does not demand additional sensitization. Quartz-enhanced conductance spectroscopy (QECS) was combined with the SSM-QTF to access humidity sensing sensitively. The results indicate that the resonance frequency of the SSM-QTF decreased monotonously with the ambient humidity. The detection sensitivity of the proposed SSM-QTF sensor was 12.7 ppm at 1 min. The SSM-QTF sensor showed good linearity of ~0.99. Using this sensor, we successfully measured the humidity of disposable medical masks for different periods of wearing time. The results showed that even a 20 min wearing time can lead to a >70% humidity in the mask enclosed space. It is suggested that a disposable medical mask should be changed

Due to the high demand for structural reliability, Structural Health Monitoring (SHM) has drawn intensive attention. Fiber Bragg Grating (FBG) sensor with many advantages has become one of the most promising sensing elements in this area. However, the axial sensitivity, as the main parameter of the FBG sensor, has received little attention. This paper tried to explore the influence of the ply stacking of composite on the axial sensitivity of the FBG sensor. The calibration test, the repeatability test, and the influence test had been carried out in this paper. Thereinto, the theoretical axial strain sensitivity of the FBG sensor (1.06312 pm/με) was obtained by the calibration test. The repeatability test verified that the effect of preparation and operating conditions on the test results could be ignored, while the influence test was used to demonstrate that the three kinds of stacking could affect the axial sensitivities of the FBG sensors. The experimental results showed that: the axial sensitivities of two FBG sensors embedded between 45°/45° layers were equal. But, a difference was observed between the FBG sensors embedded between the layers of 0°/0°, 45°/45°, and 90°/90°. The maximum relative difference was about 2.587%. It indicated that the laying sequence of the FBG sensor influenced the axial sensitivity of the FBG sensor. Subsequently, the ANSYS software was adopted to simulate the deformation distribution of the sensor under a tensile load of 800N. A good agreement was observed between the numerical prediction and experimental results.

Coronavirus disease (COVID-19), caused by SARS-CoV-2, evolved into a global pandemic in 2020, and the outbreak has taken an enormous toll on individuals, families, communities and societies around the world. One practical and effective strategy is to implement rapid case identification based on a rapid testing to respond to this public health crisis. Currently, the available technologies used for rapid diagnostics include RT-PCR, RT-LAMP, ELISA and NGS. Still, due to their different limitations, they are not well suited for rapid diagnosis in a variety of locations. Paper-based devices are alternative approaches to achieve rapid diagnosis, which are cost-effective, highly selective, sensitive, portable, and easy-to-use. In addition to individual virus screening, wastewater-based epidemiology has been emerged to be an effective way for early warning of outbreak within the population, which tests viral genome sequence to reflect information on the spread and distribution of the virus because SARS-CoV-2 can be shed into wastewater through the feces and urine from infected population. In this paper, we describe paper-based device as a low-cost and rapid sensor for both diagnosis and testing of sewage for early warning of outbreak. More importantly, the device has great potential for real-time detection in the field, without any advanced facilities or well-trained and skilled personnel, and provides early warning or timely intervention of an outbreak of pandemic.

Objective: The main objective is to study the electrodermal energy wave at some acupuncture points on Chinese people with different ages. Methods: The electrodermal screening device MORA-Super (German) was applied to measure the electrodermal energy at 38 acupuncture points and nonacupuncture points on 3949 candidates. Results: There are five groups, including 17 cases ≤12 year, 41 cases between 13 and 18 years, 722 cases between 19 and 39 years, 2995 cases between 40 and 59 years, and 174 cases ≥60 years. The electrodermal energy of candidates older than 60 years increased significantly compared with other groups (P < 0.01). There is positive correlation between electrodermal energy and age (R = 0.582). Conclusion: The electrodermal energy may become a biomarker of aging.

Multiple modifications to the structure of curcumin have been investigated with an aim to improve its potency and biochemical properties. Previously, we have synthesized a series of curcumin analogs. In the present study, the anticancer effect of 2-pyridyl cyclohexanone, one of the curcumin analogs, on esophageal carcinoma Eca109 and EC9706 cell lines and its molecular mechanisms were investigated. 2-Pyridyl cyclohexanone inhibited the proliferation of Eca109 and EC9706 cells by inducing apoptosis as indicated by morphological changes, membrane phospholipid phosphatidylserine ectropion, caspase 3 activation, and cleavage of poly(ADP-ribose) polymerase. Mechanistic studies indicated that 2-pyridyl cyclohexanone disrupted mitochondrial membrane potential, disturbed the balance of the Bcl-2 family proteins, and triggered apoptosis via the mitochondria-mediated intrinsic pathway. In 2-pyridine cyclohexanone-treated cells, the phosphorylation levels of JAK2 and STAT3 were dose-dependently decreased and p38 and p-ERK signals were notably activated in a dose-dependent manner. Moreover, we found that the addition of S3I-201, a STAT3 inhibitor, led to a decreased expression level of Bcl-2 in Eca109 cells. The chromatin immunoprecipitation assay demonstrated that STAT3 bound to the promoter of Bcl-2 in the Eca109 cells. Furthermore, the mutation of four STAT3 binding sites (−1733/−1723, −1627/−1617, −807/−797, and −134/−124) on the promote of Bcl-2 gene alone attenuated the transcriptional activation of STAT3. In addition, down-regulation of STAT3 resulted in less of transcriptional activity of STAT3 on Bcl-2 expression. These data provide a potential molecular mechanism of the apoptotic induction function of 2-pyridyl cyclohexanone, and emphasize its important roles as a therapeutic agent for esophageal squamous carcinoma.

In recent years, dye wastewater caused serious effects on environmental ecology and human health. Thus, in the present study, hydroxylamine (HA) was used to improve the Fe3O4/H2O2 process for removing the typical dye pollutant (tartrazine). Only 2.8% tartrazine could be removed in Fe3O4/H2O2 system within 60 min at the reaction of 1 g/L Fe3O4, 1 mM H2O2, and pH 4 while 97.5% tartrazine could be removed within 20 min after adding 1 mM HA into the Fe3O4/H2O2 system. Compared with Fe3O4/H2O2 system, the removal rate for removing tartrazine in Fe3O4/H2O2 system could enhance more than 100 times. Electron paramagnetic re-sonance tests (EPR), radical quenching experiments and quantitative determination demonstrated that •OH was the major reactive species for removing tartrazine in Fe3O4-HA/H2O2 system and •OH produced concentration in Fe3O4-HA/H2O2 system was also much higher than that in Fe3O4/H2O2 system. The key factors affecting tartrazine removal in Fe3O4-HA/H2O2 system were also conducted. The optimal HA dosage, Fe3O4 dosage, and H2O2 dosage was 1 mM, 1 g/L and 1 mM. The optimal initial pH in Fe3O4-HA/H2O2 system was 3, but compared with Fe3O4/H2O2 system, the tatrazine removal efficiency could significantly improve under any initial pH condition. Fe3O4-HA/H2O2 process had strong adaptability to inorganic ions and good applicability to different pollutants. Fe3O4-HA/H2O2 process also exhibited good recycle ability for tartrazine removal. Overall, Fe3O4-HA/H2O2 process is an effective and good practical applicability approach for dye wastewater treatment. [ABSTRACT FROM AUTHOR]

Oxidative stress, which can be activated by a variety of environmental risk factors, has been implicated as an important pathogenic factor for inflammatory bowel disease (IBD). However, how oxidative stress drives IBD onset remains elusive. Here, we found that oxidative stress was strongly activated in inflamed tissues from both ulcerative colitis patients and Crohn's disease patients, and it caused nuclear-to-cytosolic TDP-43 transport and a reduction in the TDP-43 protein level. To investigate the function of TDP-43 in IBD, we inducibly deleted exons 2 to 3 of Tardbp (encoding Tdp-43) in mouse intestinal epithelium, which disrupted its nuclear localization and RNA-processing function. The deletion gave rise to spontaneous intestinal inflammation by inducing epithelial cell necroptosis. Suppression of the necroptotic pathway with deletion of Mlkl or the RIP1 inhibitor Nec-1 rescued colitis phenotypes. Mechanistically, disruption of nuclear TDP-43 caused excessive R-loop accumulation, which triggered DNA damage and genome instability and thereby induced PARP1 hyperactivation, leading to subsequent NAD+ depletion and ATP loss, consequently activating mitochondrion-dependent necroptosis in intestinal epithelial cells. Importantly, restoration of cellular NAD+ levels with NAD+ or NMN supplementation, as well as suppression of ALKBH7, an α-ketoglutarate dioxygenase in mitochondria, rescued TDP-43 deficiency-induced cell death and intestinal inflammation. Furthermore, TDP-43 protein levels were significantly inversely correlated with γ-H2A.X and p-MLKL levels in clinical IBD samples, suggesting the clinical relevance of TDP-43 deficiency-induced mitochondrion-dependent necroptosis. Taken together, these findings identify a unique pathogenic mechanism that links oxidative stress to intestinal inflammation and provide a potent and valid strategy for IBD intervention. [ABSTRACT FROM AUTHOR]