DeepCBA: a deep learning framework for gene expression prediction in maize based on DNA sequence and chromatin interaction.

Chromatin interactions create spatial proximity between distal regulatory elements and target genes in the genome, which has an important impact on gene expression, transcriptional regulation, and phenotypic traits. To date, several methods have been developed for predicting gene expression. However, existing methods do not take into consideration the impact of chromatin interactions on target gene expression, thus potentially reduces the accuracy of gene expression prediction and mining of important regulatory elements. In this study, a highly accurate deep learning-based gene expression prediction model (DeepCBA) based on maize chromatin interaction data was developed. Compared with existing models, DeepCBA exhibits higher accuracy in expression classification and expression value prediction. The average Pearson correlation coefficients (PCC) for predicting gene expression using gene promoter proximal interactions, proximal-distal interactions, and proximal and distal interactions were 0.818, 0.625, and 0.929, respectively, representing an increase of 0.357, 0.16, and 0.469 over the PCC of traditional methods that only use gene proximal sequences. Some important motifs were identified through DeepCBA and were found to be enriched in open chromatin regions and expression quantitative trait loci (eQTL) and have the molecular characteristic of tissue specificity. Importantly, the experimental results of maize flowering-related gene ZmRap2.7 and tillering-related gene ZmTb1 demonstrate the feasibility of DeepCBA in exploring regulatory elements that affect gene expression. Moreover, the promoter editing and verification of two reported genes (ZmCLE7, ZmVTE4) demonstrated new insights of DeepCBA in precise designing of gene expression and even future intelligent breeding. DeepCBA is available at http://www.deepcba.com/ or http://124.220.197.196/.

An overview of detecting gene-trait associations by integrating GWAS summary statistics and eQTLs.

Detecting genes that affect specific traits (such as human diseases and crop yields) is important for treating complex diseases and improving crop quality. A genome-wide association study (GWAS) provides new insights and directions for understanding complex traits by identifying important single nucleotide polymorphisms. Many GWAS summary statistics data related to various complex traits have been gathered recently. Studies have shown that GWAS risk loci and expression quantitative trait loci (eQTLs) often have a lot of overlaps, which makes gene expression gradually become an important intermediary to reveal the regulatory role of GWAS. In this review, we review three types of gene-trait association detection methods of integrating GWAS summary statistics and eQTLs data, namely colocalization methods, transcriptome-wide association study-oriented approaches, and Mendelian randomization-related methods. At the theoretical level, we discussed the differences, relationships, advantages, and disadvantages of various algorithms in the three kinds of gene-trait association detection methods. To further discuss the performance of various methods, we summarize the significant gene sets that influence high-density lipoprotein, low-density lipoprotein, total cholesterol, and triglyceride reported in 16 studies. We discuss the performance of various algorithms using the datasets of the four lipid traits. The advantages and limitations of various algorithms are analyzed based on experimental results, and we suggest directions for follow-up studies on detecting gene-trait associations.

Characteristics and phylogenetic analysis of the complete chloroplast genome of Primulina hedyotidea.

Primulina hedyotidea (Woon Young Chun) Yin Zheng Wang 2011 is an important medicinal plant that has a long history of medicinal use in China. In this experiment, the whole chloroplast genome of P. hedyotidea was determined by next-generation sequencing technology. The total base length of P. hedyotidea was 153,297 bp, the GC content was 37.62%, the inverted repeat (IR) region length was 25,494 bp, the large single copy (LSC) region was 84,158 bp and the small single copy (SSC) region was 18,151 bp. In addition, the genome consisted of 80 protein-coding genes, 4 rRNA genes, and 28 tRNA genes, for a total of 112 genes. A phylogenetic tree was constructed to explore the evolutionary relationship between P. hedyotidea and other species. The findings of phylogenetic tree analysis show that Primulina huaijiensis and P. hedyotidea have a close relationship, and this study can help with species identification and phylogenetic analysis within Primulina and Gesneriaceae species.

Hydrogen production by traditional and novel alkaline water electrolysis on nickel or iron based electrocatalysts.

Hydrogen production through alkaline water electrolysis holds great promise as a scalable solution for renewable energy storage and conversion. The development of non-precious metal-based electrocatalysts with low-overpotential for alkaline water electrolysis is essential to decrease the cost of electrolysis devices. Although the Ni-based and Fe-based electrocatalysts have been commercially employed in the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER), it is imperative to persistently pursue the advancement of highly efficient electrocatalysts with enhanced current density and fast kinetics. This feature article overviews the progress of NiMo HER cathodes and NiFe OER anodes in the traditional alkaline water electrolysis process for hydrogen production, including the detailed mechanisms, preparation strategies, and structure-function relationship. Moreover, recent advances of Ni-based and Fe-based electrodes in the process of novel alkaline water electrolysis, involving small energetic molecule electro-oxidation and redox mediator decoupled water electrolysis, are also discussed for hydrogen production with low cell voltage. Finally, the perspective of these Ni-based and Fe-based electrodes in the mentioned electrolysis processes is proposed.

Zn and N co-doped three-dimensional honeycomb-like carbon featured with interconnected nano-pools for dendrite-free zinc anode.

The zinc-ion battery (ZIB) has been extensively researched as one of the promising electrochemical power sources. However, the problem of Zn-dendrite formation during repeated plating and stripping process seriously hinders the development of ZIBs. Herein, three-dimensional (3D) honeycomb-like porous carbon (HPC) with co-doping of zinc and nitrogen is prepared through confining growth of nanoscale zeolite imidazole framework-8 (ZIF-8) on the well-designed nano-pools walls of HPC followed by pyrolysis at 600 ℃ to obtain the final product ZnN/HPC-600, which exhibits large surface area and abundant zincophilic interfaces, ensuring homogeneous distribution of electronic field and low polarization during cycling process. Importantly, ZnN/HPC-600 facilitates the uniform distribution and migration of Zn2+ in this nano-pools structure, avoiding the growth of dendritic Zn crystal during charging stage. The symmetric and asymmetric cells with Zn/ZnN/HPC-600 anodes are assembled, demonstrating excellent cycling reversibility, good rate performance and long-term stability. Besides, a Zn||MnO2 full cell with Zn/ZnN/HPC-600 anode also exhibits robust cycling stability, fast reaction kinetics and almost 100 % coulombic efficiency. This work offers a novel and efficient carbonaceous nano-pools strategy to realize dendrite-free zinc anode in ZIBs.

Carbon Coated and Nitrogen Doped Hierarchical NiMo-Based Electrocatalysts with High Activity and Durability for Efficient Borohydride Oxidation.

Sodium borohydride is a promising candidate as hydrogen storage material. The direct borohydride fuel cell (DBFC) as an energy conversation device has attracted intensive attention owing to the low theoretical potential of borohydride oxidation reaction (BOR, -1.24 V vs SHE) on the anode. In this paper, the hierarchical sea urchin-like NiMoN@NC coated by thin carbon layer with optimal BH4- adsorption characteristic was synthesized as a superior electrocatalyst toward BOR. In 1 M NaOH-0.05 M NaBH4, the BOR working potentials are only -55 and 44 mV at the current densities of 10 and 200 mA cm-2 on NiMoN@NC, respectively. Furthermore, the membrane-free DBFC using NiMoN@NC as anodic electrocatalyst shows a maximum power density of 67 mW cm-2 at room temperature with appreciative stability. This well-designed carbon coated and nitrogen doped transition-metal material with hierarchical nano/microstructure as a highly efficient electrocatalyst shows promising potential and bright prospects in electrocatalysis research and practical application for energy conversion systems of DBFC.

Electrochemically controlled ON/OFF switching of NaBH4 hydrolysis based on NiMoN@NC for on-demand hydrogen production.

A facile and novel electrochemically controlled ON/OFF switching of NaBH4 hydrolysis is proposed for on-demand hydrogen production. A low potential can activate the catalyst to the ON state by promoting the adsorption and hydrolysis of BH4-, while a high potential can deactivate the catalyst to the OFF state by inhibiting the chemical hydrolysis.

Fe-ZIF8 Coating Cu Foil Derived Carbon as A pH-Universal Electrocatalyst for Efficient Oxygen Reduction Reaction.

It is a great challenge to fabricate highly efficient pH-universal electrocatalysts for oxygen reduction reaction (ORR). Herein, a facile strategy, which includes coating the Fe modified ZIF8 on Cu foil and in situ pyrolysis to evaporate and dope Cu into the MOF derived carbon, is developed to fabricate Fe/Cu-N co-doped carbon material (Cu/Fe-NC). Profiting from the modulated electron distribution and textual properties, well-designed Cu/Fe-NC exhibits superior half-wave potential (E1/2 ) of 0.923 V in alkaline, 0.757 V in neutral and comparable 0.801 V in acid electrolytes, respectively. Furthermore, the ultralow peroxides yield of ORR demonstrates the high selectivity of Cu/Fe-NC in full pH scale electrolytes. As expected, the self-made alkaline and neutral zinc-air batteries equipped with Cu/Fe-NC cathode display excellent discharge voltages, outstanding peak power densities and remarkable stability. This work opens a new way to fabricate highly efficient and pH-universal electrocatalysts for ORR through strategy of Fe/Cu-N co-doping, Cu foil evaporation and carbon defects capture.

Influence of Diet on the Effect of the Probiotic Lactobacillus paracasei in Rats Suffering From Allergic Asthma.

Mounting evidence suggests that probiotics can be used to treat allergic asthma by modulating the gut microbiota, and that the effects of probiotics may be influenced by environmental factors such as diet. We conducted a rat model with allergic asthma (AA) modulated by Lactobacillus paracasei, feeding up with high-fat or high-fiber diets based on collecting data from 85 questionnaires. The systemic proinflammatory cytokines were detected by ELISA and the overall structure of fecal microbiota was analyzed via 16S rRNA gene sequencing. The results showed consumption of a high-fiber diet alleviated the allergic symptoms and airway inflammation, and led to improving the imbalance of T-helper type 1 (Th1)/Th2 cells with increased expression of interferon-γ and decreased expression of interleukin-4. Whereas, the high-fat diet had deteriorating implications and skewed the inflammatory perturbation. Furthermore, abundances of phylum Bacteroidetes, families Muribaculaceae, Tannerellaceae, Prevotellaceae, Enterococcaceae, genera Allobaculum, Parabacteroides, and Enterococcus were enriched in L. paracasei-modulating rats fed with high-fiber diet. Firmicutes and Proteobacteria, families Lachnospiraceae, Ruminococcaceae and Desulfovibrionaceae, genera Blautia, unidentified_Ruminococcaceae, unidentified_Clostridiales and Oscillibacter were in relatively high abundance in the rats administered high-fat diet. Association between changed microbiota and inflammatory cytokines was also conferred. These data indicated that the efficacy of L. paracasei in allergic asthma was influenced by different dietary patterns. Hence, diet is important for probiotic therapy when managing allergic asthma.

Evaluation of electrical current production in microbial electrolysis cells fed with animal rendering wastewater.

Anode-respiring bacteria (ARB) generate electrical current from the oxidation of short chain fatty acids (SCFA), primarily acetate, in microbial electrolysis cells (MECs). Animal rendering wastewater (RW) has high fat content, which under anaerobic conditions can yield acetate, making RW a potential feed for MECs. Yet, excess intermediate long chain fatty acids (LCFA) may limit conversion of LCFA and SCFA, and impact ARB activity. Here, we evaluated electrical current production in single-chamber MECs fed with RW. In RW-fed MECs, 34.26 ± 2.69% of the COD provided was converted to electrical current in an 80-day batch cycle. LCFA accumulated in RW-fed MECs, during which conversion of acetate to electrical current was limited. Diverse sulfate-reducing microorganisms were present in the anode biofilm in RW-fed MECs, whereas the genus Geobacter dominated in inoculum-only control MECs. Detection of H2-utilizing homoacetogens suggested some internal cycling of H2 produced at the cathode. Overall, this study shows that current production is possible from RW, but to be a viable process for RW treatment, further improvement in rates of COD conversion and current production is necessary along with identifying configurations and/or conditions in which the inhibitory effect of LCFA is reduced.

Distinct Clinical Pathology and Microbiota in Chronic Rhinosinusitis With Nasal Polyps Endotypes.

OBJECTIVES/HYPOTHESIS: Eosinophilic and noneosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP and NECRSwNP) show distinguished clinical pathology, but their underlying mechanism remains unclear. We aimed to investigate the clinical, hematological, and histopathological changes in chronic rhinosinusitis with nasal polyps (CRSwNP) endotypes and its association with microbiota. STUDY DESIGN: A comparative cross-sectional study. METHODS: A comparative study of 46 patients with CRSwNP (34.69 ± 16.39 years old) who underwent endoscopic sinus surgery were recruited and subdivided into ECRSwNP and NECRSwNP groups based on eosinophilic tissue inflammation; 12 healthy controls were also included. A structured histopathological analysis was conducted, and complete blood count was determined in patients. Endoscopic-guided middle meatus swabs and fecal samples were collected from the patients and controls and subsequently subjected to 16S rRNA gene sequencing on Illumina MiSeq. RESULTS: Compared to NECRSwNP, ECRSwNP showed a statistically significant increase in the computed tomography score, endoscopic score, blood eosinophil percentage, tissue eosinophil count, inflammation degree, subepithelial edema, and eosinophil aggregation. Airway microbiota communities differed among the three groups. The abundance of Moraxella and Parvimonas was significantly higher in the ECRSwNP group. Distinct microbiota dysbiosis in CRSwNP endotypes was found to be correlated with different clinical pathologies. Moreover, the gut microbiota in ECRSwNP and NECRSwNP showed dysbiosis, that is, significant decrease in the abundance of Actinobacteria in the former and significant increase in the abundance of Enterobacterales and several genera in NECRSwNP. CONCLUSIONS: Significant clinical pathology and microbiota changes were evident in patients with ECRSwNP and NECRSwNP. Distinct microbiota dysbiosis was correlated with different clinical pathologies. Understanding these differences may improve the prognosis and treatment of chronic rhinosinusitis. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E34-E44, 2021.

Tau acetylates and stabilizes ß-catenin thereby promoting cell survival.

Overexpressing Tau counteracts apoptosis and increases dephosphorylated ß-catenin levels, but the underlying mechanisms are elusive. Here, we show that Tau can directly and robustly acetylate ß-catenin at K49 in a concentration-, time-, and pH-dependent manner. ß-catenin K49 acetylation inhibits its phosphorylation and its ubiquitination-associated proteolysis, thus increasing ß-catenin protein levels. K49 acetylation further promotes nuclear translocation and the transcriptional activity of ß-catenin, and increases the expression of survival-promoting genes (bcl2 and survivin), counteracting apoptosis. Mutation of Tau's acetyltransferase domain or co-expressing non-acetylatable ß-catenin-K49R prevents increased ß-catenin signaling and abolishes the anti-apoptotic function of Tau. Our data reveal that Tau preserves ß-catenin by acetylating K49, and upregulated ß-catenin/survival signaling in turn mediates the anti-apoptotic effect of Tau.

Preparation of nonconjugated fluorescent polymer nanoparticles for use as a fluorescent probe for detection of 2,4,6-trinitrophenol.

Water-soluble nonconjugated fluorescent polymer nanoparticles (NFPNs) were prepared from branched polyethylenimine (PEI) and citric acid through an amide condensation reaction in the aqueous phase. The NFPNs were characterized using a transmission electron microscope, Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectra (XPS). The NFPN fluorescence (with excitation/emission peaks at 360/450 nm) was quenched by 2,4,6-trinitrophenol (TNP) at trace concentrations through the inner filter effect and the formation of self-assembled non-fluorescent Meisenheimer complexes of TNP on the NFPN surfaces through acid-base interactions. The complexes effectively enriched TNP from the bulk solution on the NFPN surfaces through acid-base interactions, and the strong overlap between NFPN excitation and TNP absorption peaks contributed to NFPNs having good sensitivity and selectivity for TNP. The method was selective for TNP and was not sensitive to other interfering species. The calibration plot of log(F0/F) versus TNP concentration shows a linear relationship (R2 = 0.999) for TNP concentration in the range of 0.5-150 µM. The detection limit for TNP was 0.7 µM. The assay was successfully used to determine TNP in spiked lake water samples, and the recoveries were 96.6-102.7%.

Enriched gestation activates the IGF pathway to evoke embryo-adult benefits to prevent Alzheimer's disease.

BACKGROUND: Building brain reserves before dementia onset could represent a promising strategy to prevent Alzheimer's disease (AD), while how to initiate early cognitive stimulation is unclear. Given that the immature brain is more sensitive to environmental stimuli and that brain dynamics decrease with ageing, we reasoned that it would be effective to initiate cognitive stimulation against AD as early as the fetal period. METHODS: After conception, maternal AD transgenic mice (3 × Tg AD) were exposed to gestational environment enrichment (GEE) until the day of delivery. The cognitive capacity of the offspring was assessed by the Morris water maze and contextual fear-conditioning tests when the offspring were raised in a standard environment to 7 months of age. Western blotting, immunohistochemistry, real-time PCR, immunoprecipitation, chromatin immunoprecipitation (ChIP) assay, electrophysiology, Golgi staining, activity assays and sandwich ELISA were employed to gain insight into the mechanisms underlying the beneficial effects of GEE on embryos and 7-10-month-old adult offspring. RESULTS: We found that GEE markedly preserved synaptic plasticity and memory capacity with amelioration of hallmark pathologies in 7-10-m-old AD offspring. The beneficial effects of GEE were accompanied by global histone hyperacetylation, including those at bdnf promoter-binding regions, with robust BDNF mRNA and protein expression in both embryo and progeny hippocampus. GEE increased insulin-like growth factor 1 (IGF1) and activated its receptor (IGF1R), which phosphorylates Ca2+/calmodulin-dependent kinase IV (CaMKIV) at tyrosine sites and triggers its nuclear translocation, subsequently upregulating histone acetyltransferase (HAT) and BDNF transcription. The upregulation of IGF1 mimicked the effects of GEE, while IGF1R or HAT inhibition during pregnancy abolished the GEE-induced CaMKIV-dependent histone hyperacetylation and BDNF upregulation. CONCLUSIONS: These findings suggest that activation of IGF1R/CaMKIV/HAT/BDNF signaling by gestational environment enrichment may serve as a promising strategy to delay AD progression.

Tau overexpression impairs neuronal endocytosis by decreasing the GTPase dynamin 1 through the miR-132/MeCP2 pathway.

Tauopathies are a class of neurodegenerative diseases that are characterized by pathological aggregation of tau protein, which is accompanied by synaptic disorders. However, the role of tau in endocytosis, a fundamental process in synaptic transmission, remains elusive. Here, we report that forced expression of human tau (hTau) in mouse cortical neurons impairs endocytosis by decreasing the level of the GTPase dynamin 1 via disruption of the miR-132-MeCP2 pathway; this process can also be detected in the brains of Alzheimer's patients and hTau mice. Our results provide evidence for a novel role of tau in the regulation of presynaptic function.

MicroRNA-26a/Death-Associated Protein Kinase 1 Signaling Induces Synucleinopathy and Dopaminergic Neuron Degeneration in Parkinson's Disease.

BACKGROUND: Death-associated protein kinase 1 (DAPK1) is a widely distributed serine/threonine kinase that is critical for cell death in multiple neurological disorders, including Alzheimer's disease and stroke. However, little is known about the role of DAPK1 in the pathogenesis of Parkinson's disease (PD), the second most common neurodegenerative disorder. METHODS: We used Western blot and immunohistochemistry to evaluate the alteration of DAPK1. Quantitative polymerase chain reaction and fluorescence in situ hybridization were used to analyze the expression of microRNAs in PD mice and patients with PD. Rotarod, open field, and pole tests were used to evaluate the locomotor ability. Immunofluorescence, Western blot, and filter traps were used to evaluate synucleinopathy in PD mice. RESULTS: We found that DAPK1 is posttranscriptionally upregulated by a reduction in microRNA-26a (miR-26a) caused by a loss of the transcription factor CCAAT enhancer-binding protein alpha. The overexpression of DAPK1 in PD mice is positively correlated with neuronal synucleinopathy. Suppressing miR-26a or upregulating DAPK1 results in synucleinopathy, dopaminergic neuron cell death, and motor disabilities in wild-type mice. In contrast, genetic deletion of DAPK1 in dopaminergic neurons by crossing DAT-Cre mice with DAPK1 floxed mice effectively rescues the abnormalities in mice with chronic MPTP treatment. We further showed that DAPK1 overexpression promotes PD-like phenotypes by direct phosphorylation of α-synuclein at the serine 129 site. Correspondingly, a cell-permeable competing peptide that blocks the phosphorylation of α-synuclein prevents motor disorders, synucleinopathy, and dopaminergic neuron loss in the MPTP mice. CONCLUSIONS: miR-26a/DAPK1 signaling cascades are essential in the formation of the molecular and cellular pathologies in PD.

Intestinal Microbiota and Kidney Diseases.

Kidney diseases are common and the incidence rate is increasing. Gut microbiota is involved in metabolic and immune regulation of the host. Genetic, alimentary and environmental disease factors may change gut flora and increase opportunistic and pathogenic bacteria, contributing to immune or non-immune mediated kidney diseases including IgA nephropathy and diabetic nephropathy. Additionally, bacterial metabolites may be a source of uremic toxins. Thus, identification of diversity, composition, and metabolic and immunologic features of gut bacteria in chronic kidney diseases may help understand pathogenetic mechanism and develop therapy for diseases.

Synaptic Dysfunction in Alzheimer's Disease: Aß, Tau, and Epigenetic Alterations.

Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized in the early stages by loss of learning and memory. However, the mechanism underlying these symptoms remains unclear. The best correlation between cognitive decline and pathological changes is in synaptic dysfunction. Histopathological hallmarks of AD are the abnormal aggregation of Aß and Tau. Evidence suggests that Aß and Tau oligomers contribute to synaptic loss in AD. Recently, direct links between epigenetic alterations, such as dysfunction in non-coding RNAs (ncRNAs), and synaptic pathologies have emerged, raising interest in exploring the potential roles of ncRNAs in the synaptic deficits in AD. In this paper, we summarize the potential roles of Aß, Tau, and epigenetic alterations (especially by ncRNAs) in the synaptic dysfunction of AD and discuss the novel findings in this area.

GSK-3ß deletion in dentate gyrus excitatory neuron impairs synaptic plasticity and memory.

Increasing evidence suggests that glycogen synthase kinase-3ß (GSK-3ß) plays a crucial role in neurodegenerative/psychiatric disorders, while pan-neural knockout of GSK-3ß also shows detrimental effects. Currently, the function of GSK-3ß in specific type of neurons is elusive. Here, we infused AAV-CaMKII-Cre-2A-eGFP into GSK-3ßlox/lox mice to selectively delete the kinase in excitatory neurons of hippocampal dentate gyrus (DG), and studied the effects on cognitive/psychiatric behaviors and the molecular mechanisms. We found that mice with GSK-3ß deletion in DG excitatory neurons displayed spatial and fear memory defects with an anti-anxiety behavior. Further studies demonstrated that GSK-3ß deletion in DG subset inhibited hippocampal synaptic transmission and reduced levels of GluN1, GluN2A and GluN2B (NMDAR subunits), GluA1 (AMPAR subunit), PSD93 and drebrin (postsynaptic structural proteins), and synaptophysin (presynaptic protein). GSK-3ß deletion also suppressed the activity-dependent neural activation and calcium/calmodulin-dependent protein kinase II (CaMKII)/CaMKIV-cAMP response element binding protein (CREB) signaling. Our data suggest that GSK-3ß in hippocampal DG excitatory neurons is essential for maintaining synaptic plasticity and memory.

Hierarchical Porous Carbon Doped with Iron/Nitrogen/Sulfur for Efficient Oxygen Reduction Reaction.

Hierarchical porous Fe/N/S-doped carbon with a high content of graphitic nitrogen (FeNS/HPC) has been successfully synthesized by a facile dual-template method. FeNS/HPC shows not only macropores resulting from the dissolution of the SiO2 template, but abundant mesopores were also obtained after removing the in situ generated Fe2O3 nanoparticles on the ultrathin (∼4 nm) carbon shell of the macropores. Moreover, micropores are produced during the thermal pyrolysis of the carbon precursors. With respect to the electrochemical performance in the oxygen reduction reaction (ORR), FeNS/HPC not only exceeds other prepared porous carbon materials completely but also shows higher onset potential (0.97 vs 0.93 V), half-wave potentials (0.87 vs 0.83 V), and diffusion current density (5.5 vs 5.3 mA cm-2) than those of Pt/C. Furthermore, FeNS/HPC also exhibits outstanding stability and methanol tolerance, making it a competent candidate for ORR. The following aspects contribute to its excellent ORR performance. (1) High content of graphitic N (5.1%) and codoping of pyridinic N species, thiophene-S, FeNx, and graphitic carbon-encapsulated iron nanoparticles, providing highly active sites. (2) The hierarchical porous mesh structure with micro-, meso-, and macroporosity, accelerating the mass transfer and facilitating full utilization of the active sites. (3) The high specific surface area (1148 m2 g-1) of the graphitic carbon shell, assuring a large interface and rapid electron conduction for ORR.