Haocheng Zhang

Abstract Although atomically dispersed Fe‐N 4 on carbon materials (Fe‐NC) have enormous potential for the oxygen reduction reaction (ORR), precise control over the electronic structure of Fe to enhance the catalytic performance and a full understanding of the catalytic mechanism remain elusive. Herein, a novel approach is designed to boost the kinetic activity of single Fe‐N 4 centers by controlling S‐doped content and species (namely, thiophene‐like S and oxidized S). Due to confinement and catalysis effects, the innovative strategy of combining a Mg(OH) 2 template with KOH activation preferentially generates oxidized S and simultaneously constructs porous carbon with a high Fe loading (2.93 wt%) and hierarchical pores. Theoretical calculations suggest that neighboring S functionalities can affect the electronic configurations of Fe‐N 4 sites and increase the electron density around Fe atoms, thereby optimizing the adsorption energy of intermediates and substantially accelerating reaction kinetics, following the trend: oxidized S doped > thiophene‐like S doped > pristine Fe‐N 4 . Benefiting from high activity and accessibility of Fe‐N 4 sites, the optimal FeNC‐SN‐2 electrode displays impressive ORR activity with large power density while maintaining outstanding durability in Zn‐air batteries and microbial fuel cells. The work paves the way to prepare stable single‐atom metal‐N x sites with heteroatom‐doping for diverse high‐performance applications.

Abstract Background Accurate etiology diagnosis is crucial for central nervous system infections (CNS infections). The diagnostic value of metagenomic next-generation sequencing (mNGS), an emerging powerful platform, remains to be studied in CNS infections. Methods We conducted a single-center prospective cohort study to compare mNGS with conventional methods including culture, smear and etc. 248 suspected CNS infectious patients were enrolled and clinical data were recorded. Results mNGS reported a 90.00% (9/10) sensitivity in culture-positive patients without empirical treatment and 66.67% (6/9) in empirically-treated patients. Detected an extra of 48 bacteria and fungi in culture-negative patients, mNGS provided a higher detection rate compared to culture in patients with (34.45% vs. 7.56%, McNemar test, p < 0.0083) or without empirical therapy (50.00% vs. 25.00%, McNemar test, p > 0.0083). Compared to conventional methods, positive percent agreement and negative percent agreement was 75.00% and 69.11% separately. mNGS detection rate was significantly higher in patients with cerebrospinal fluid (CSF) WBC > 300 * 10 6 /L, CSF protein > 500 mg/L or glucose ratio ≤ 0.3. mNGS sequencing read is correlated with CSF WBC, glucose ratio levels and clinical disease progression. Conclusion mNGS showed a satisfying diagnostic performance in CNS infections and had an overall superior detection rate to culture. mNGS may held diagnostic advantages especially in empirically treated patients. CSF laboratory results were statistically relevant to mNGS detection rate, and mNGS could dynamically monitor disease progression.

Abstract Nitrogen‐coordinated single‐atom catalysts (SACs) have emerged as a new frontier for accelerating oxygen reduction reaction (ORR) owing to the optimal atom efficiency and fascinating properties. However, augmenting the full exposure of active sites is a crucial challenge in terms of simultaneously pursuing high metal loading of SACs. Here, petal‐like porous carbon nanosheets with densely accessible Fe‐N 4 moieties (FeNC‐D) are constructed by combining the space‐confinement of silica and the coordination of diethylenetriaminepentaacetic acid. The resulted FeNC‐D catalyst possesses an enhanced mesoporosity and a balanced hydrophobicity/hydrophilicity, which can facilitate mass transport and advance the exposure of inaccessible Fe‐N 4 sites, resulting in efficient utilization of active sites. By virtue of the petal‐like porous architecture with maximized active site density, FeNC‐D demonstrates superior ORR performance in a broad pH range. Remarkably, when utilized as the air cathode in Zn‐air battery (ZAB) and microbial fuel cell (MFC), the FeNC‐D‐based device displays a large power density (356 mW cm −2 for ZAB and 1041.3 mW m −2 for MFC) and possesses remarkable stability, substantially outperforming the commercial Pt/C catalyst.

Long COVID hinders people from normal life and work, posing significant medical and economic challenges. Nevertheless, comprehensive studies assessing its impact on large populations in Asia are still lacking. We tracked over 20,000 patients infected with COVID-19 for the first time during the Omicron BA.2 outbreak in Shanghai from March-June 2022 for one year. Of the 21,799 COVID-19 patients who participated in the 6-month telephone follow-up, 1939 (8.89%) had self-reported long COVID symptoms. 450 long COVID patients participated in the 6-month outpatient follow-up. Participants underwent healthy physical examinations and questionnaires focused on long-COVID-related symptoms and mental health. Mobility problem (P < 0.001), personal care problem (P = 0.003), usual activity problem (P < 0.001), pain/discomfort (P < 0.001), anxiety/depression (P = 0.001) and PTSD (P = 0.001) were more prevalent in long COVID patients than in healthy individuals, but no significant differences were found between the two groups on chest CT and laboratory examinations. Of the 856 long COVID patients who participated in the 12-month follow-up, 587 (68.5%) had their symptoms resolved. In the multivariable logistic analysis, females (P < 0.001), youth (age <40 years) (P < 0.001), ≥ 2 comorbidities (P = 0.009), and severe infection in the acute phase (P = 0.006) were risk factors for developing long COVID. Middle age (40–60 years) was a risk factor for persistent long COVID one year after hospital discharge (P = 0.013). The study found that long COVID mainly manifested as subjective symptoms and impacts partial patients’ quality of life and mental status. After one year, most (68.5%) of the patients recovered from long COVID with no impairment of organ function observed.