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Single metal atoms immobilized on a carbon substrate are of great potential for enhancing the catalytic activities for oxygen reduction and methanol oxidation reactions (ORR/MOR) owing to the maximized atom utilization. Herein, single copper atoms (SCAs) are loaded on macro-porous nitrogen-doped carbon (Cu-NC) derived from zeolitic imidazolate framework-8 (ZIF-8), which are used as catalysts for ORR and Pt-supports for MOR. For ORR, the catalyst marked as Cu-NC-3 exhibits a higher peak potential of 0.87 V (vs. Reversible hydrogen electrode) than that of commercial Pt/C (0.83 V), mainly attributing to that the 3D macro-porous structure of Cu-NC-3 provides adequate space for uniform dispersion of SCAs as the main active species, and smooth diffusion pathways for fast transport of substances (O2, H2O), therefore reducing the overpotential and the intermediate (H2O2) generation to enhance ORR activity. For MOR, Pt-Cu-NC-3 has a higher mass activity of 1217.4 mA/mgPt than that of Pt/C (752.4 mA/mgPt), and its activity maintenance (decline of 27.6%) is also better than Pt/C (decline of 44.0%) after 5000 cyclic voltammetry (CV) cycles. The interactions between SCAs and Pt nanoparticles should facilitate the generation of OH− from water molecules, which can fast eliminate the adsorbed CO to recover the Pt active sites to improve MOR performance. This synthesis strategy affords a new inspiration to prepare single metal atoms loaded on ZIFs-derived macro-structure with diverse activities for ORR/MOR.

Black soldier fly larvae (Hermetia illucens L. BSFL) bioconversion is a promising biotechnology for food waste treatment. However, the separated residues still do not meet criteria for use as land application biofertilizers. In this work, we investigated a full-scale BSFL bioconversion project to explore features of dissolved organic matter (DOM) and its associated responses of bacterial community succession in residue during secondary composting. Data showed that the concentrations of total nitrogen and ammonium nitrogen decreased by 11.8% and 22.6% during the secondary composting, respectively, while the nitrate nitrogen concentration increased 18.7 times. The DOM concentration decreased by 69.1%, in which protein-like, alcohol-phenol, and biodegradable aliphatic substances were metabolized by bacteria during the thermophilic phase together with the accumulation of humus-like substances, resulting in an increase in the relative concentration of aromatic compounds. The structure of the bacterial community varied at different stages of the bioprocess, in which Bacteroidetes, Actinobacteria, Proteobacteria, and Firmicutes were the dominant bacterial phyla. Lysinibacillus, Pusillimonas, and Caldicoprobacter were found to be key contributors in the degradation and formation of DOM. The DOM concentration (33.4%) and temperature (17.7%) were the prime environmental factors that promoted succession of the bacterial community. Through bacterial metabolism, the structural stability of DOM components was improved during the composting process, and the degrees of humification and aromaticity were also increased. This study depicted the dynamic features of DOM and the associated bacterial community succession in residue during secondary composting, which is conducive with the reuse of BSFL residue as biofertilizer for agriculture.

Background Weaning from venovenous extracorporeal membrane oxygenation (VV-ECMO) has not been not well studied. VV-ECMO can be discontinued when patients tolerate noninjurious mechanical ventilation (MV) during a sweep gas-off trial (SGOT). However, predictors of safe liberation are unknown. Research Question Can safe liberation from VV-ECMO be predicted at the bedside? Study Design and Methods Two observational studies of adults weaned from VV-ECMO for severe ARDS at Toronto General Hospital were conducted. MV settings, respiratory mechanics, and clinical variables were analyzed to predict safe liberation from VV-ECMO, defined a priori as avoida7ce of ECMO recannulation, increased MV support, need for rescue therapy, or hemodynamic instability developed within 48 h following decannulation. Results During both studies, 83 patients were weaned from VV-ECMO, 21 (25%) of whom did not meet the criteria for safe liberation. In the retrospective study, higher tidal volume per predicted body weight (OR, 1.58; 95% CI, 1.05-2.40; P = .03) and heart rate (OR, 1.07; 95% CI, 1.022-1.15; P = .01) at the end of SGOT were significantly associated with increased odds of unsafe liberation when adjusted for age (OR, 1.02; 95% CI, 0.95-1.09; P = .63) and sequential organ failure assessment score (OR, 1.16; 95% CI, 0.86-1.56; P = .34). Change in ventilatory ratio had an imprecise association (OR, 2.7; 95% CI, 0.94-7.95; P = .06) with unsafe liberation when adjusted for age (OR, 1.03; 95% CI, 0.96-1.10; P = .42), sequential organ failure assessment score (OR, 1.11; 95% CI, 0.81-1.51; P = .52), and heart rate (OR, 1.07; 95% CI, 1.01-1.13; P = .02). In the prospective study, patients who had unsafe liberation from VV-ECMO also had significantly higher inspiratory efforts (esophageal pressure swings, 9 [7-13] vs 18 [7-25] cm H2O; P = .03) and worse outcomes (longer MV duration, ICU and hospital length of stay). Interpretation Patients with higher tidal volume, heart rate, ventilatory ratio, and esophageal pressures swings during SGOT were less likely to achieve safe liberation from VV-ECMO.

BACKGROUND Donor-recipient size-matching has been repeatedly reported to improve outcomes following lung transplantation (LTx). However, there is significant variability in practice and the optimal strategy for size-matching is yet to be defined. For recipients with ILD, size-matching decisions are complicated by concerns regarding the potential impact of pre-LTx pulmonary restriction. We evaluate whether a specific donor-to-recipient size-matching strategy, based on predicted total lung capacity, benefits this patient group. METHODS This retrospective, single-centre, cohort study describes the post-LTx outcomes of adults who underwent LTx for ILD between 1983 and 2020. Only patients with restrictive physiology, based on pre-LTx pulmonary function testing were included. Post-LTx outcomes were compared based on donor-recipient predicted TLC (D-R pTLC) ratio. A D-R pTLC ratio of ≥0.8 or

Ex vivo lung perfusion (EVLP) has being increasingly used for the pretransplant assessment of extended-criteria donor lungs. Mathematical models to predict lung acceptance during EVLP have not been reported so far. Thus, we hypothesized that predictors of lung acceptance could be identified and used to develop a mathematical model describing the clinical decision-making process used in our institution. Donor lungs characteristics and EVLP physiologic parameters included in our EVLP registry were examined (derivation cohort). Multivariable logistic regression analysis was performed to identify predictors independently associated with lung acceptance. A mathematical model (EX vivo lung PerfusIon pREdiction [EXPIRE] model) for each hour of EVLP was developed and validated using a new cohort (validation cohort). Two hundred eighty donor lungs were assessed with EVLP. Of these, 186 (66%) were accepted for transplantation. ΔPO2 and static compliance/total lung capacity were identified as independent predictors of lung acceptance and their respective cut-off values were determined. The EXPIRE model showed a low discriminative power at the first hour of EVLP assessment (AUC: 0.69 [95% CI: 0.62-0.77]), which progressively improved up to the fourth hour (AUC: 0.87 [95% CI: 0.83-0.92]). In a validation cohort, the EXPIRE model demonstrated good discriminative power, peaking at the fourth hour (AUC: 0.85 [95% CI: 0.76-0.94]). The EXPIRE model may help to standardize lung assessment in centers using the Toronto EVLP technique and improve overall transplant rates.

Summary As an analog of graphene, carbon nitrides have drawn increasing attention, ranging from artificial photosynthesis to synthetic organic chemistry. Notably, the most studied polymeric, C3N4, and other stoichiometric ones, such as C3N5, C4N3, and C3N, are commonly employed repetitive units of six-membered rings. Building blocks of five-membered rings (FMRs) are also fascinating and prevalent from a fundamental point of view, but FMR-based carbon nitrides are scarcely reported. Here, we propose a stable FMR-based C3N2 and the kinetic-oriented synthesis method via a pre-stabilization strategy using abundant-available zeolitic imidazolate framework as a precursor. The FMR topological structure and the associated dangling bonds were disclosed in C3N2, leading to an interesting p-π conjugation and splitting molecular orbitals, which remarkably narrowed the optical bandgap unusually down to 0.81 eV. The as-obtained C3N2 was further successfully applied to real-time, dynamic, and quantitative photoelectrochemical biosensing for practical non-transparent biosamples under near-infrared light irradiation.

In recent years, the incidence of myopia has increased at an alarming rate among children and adolescents in China. The exploration of an effective prevention and control method for myopia is in urgent need. With the development of information technology in the past decade, artificial intelligence with the Internet of Things technology (AIoT) is characterized by strong computing power, advanced algorithm, continuous monitoring, and accurate prediction of long-term progression. Therefore, big data and artificial intelligence technology have the potential to be applied to data mining of myopia etiology and prediction of myopia occurrence and development. More recently, there has been a growing recognition that myopia study involving AIoT needs to undergo a rigorous evaluation to demonstrate robust results.

A self-reinforced Si3N4 ceramic with high thermal conductivity was prepared through multi-step pressureless sintering with Y2O3 and MgO additives. The steps consisted of phase control and densification stages to provide additional crystallization sites using a partial α-β phase transformation, which also established a bimodal microstructure. The optimal temperature for the intermediate stage that exhibited the maximum flexural strength was determined by comparing the phase content and linear shrinkage. Thus, 1400 °C, which resulted in 14.4 wt% β-Si3N4, was found to be optimal. After final sintering, a flexural strength of 932 MPa and a thermal conductivity of 74 W/mK were achieved, which are 11.5% and 8.0% higher, respectively, than those obtained using conventional pressureless sintering. The rate constant and activation energy of the pressureless sintering with the Y2O3–MgO additive system were also calculated to evaluate the potential of the α-β transformation to obtain the proper quantity of β-Si3N4 seeds.

The nanoporous (NP) GaN wafers which were fabricated by electrochemical etching (EC) method were used as substrates to deposit Er-doped Ga2O3 epitaxial films by pulsed layer deposition (PLD). The epitaxial relationship between the GaN and Er doped β-Ga2O3 film was Ga2O3 (−201) ‖ GaN (0001) with Ga2O3 [010] ‖ GaN [-12-10]. Compared to the Er doped films on the epi-GaN wafers with the porosity of 0%, ~20% and ~60%, the β-Ga2O3 film deposited on the wafer with a porosity of ~40%, which has an energy bandgap of ~4.89 eV, has the best crystal quality and optoelectronic properties. The performance enhancement should be due to improved crystalline quality as a result of the existence of nanopores in the etched substrates. The excellent properties of Er doped Ga2O3 films indicated that the films have great potential to fabricate Ga2O3 optoelectronic devices.

Sepsis is a serious syndrome that is caused by an unbalanced inflammatory response to infection and can cause high mortality. The role of interleukin-37 (IL-37) in estimating the mortality in patients with sepsis remains unknown. This study aims to reveal the clinical application of IL-37 as a potentially novel biomarker to predict mortality risk in patients with sepsis.The serum IL-37 level in 114 adult septic patient serum samples on the day of intensive care unit (ICU) admission, 56 non-sepsis ICU patients, and 56 healthy volunteers were measured and analyzed, and the 28-day survival status and sequential organ failure assessment (SOFA) scores of the participants were compared. Furthermore, the area under the receiver operating characteristic curve (AUC) of IL-37, IL-6, and SOFA at ICU admission for 28-day survival was used to evaluate the ability of IL-37 in predicting the mortality of sepsis.The serum IL-37 level at admission was elevated in patients with sepsis. Moreover, the concentration of IL-37 in patients with sepsis was significantly higher than that in non-sepsis ICU patients and the healthy control group. In addition, the concentration of serum IL-37 in non-surviving patients with sepsis was significantly higher than that in survivors. In patients with sepsis on the day of ICU admission, the AUC associated with 28-day mortality was 0.67 (p = 0.0022;95% confidence interval [95% CI], 0.57-0.77) for IL-37, 0.75 (p0.0001; 95% CI, 0.66-0.84) for SOFA, and 0.62 (p = 0.0342; 95% CI, 0.51-0.72) for IL-6. IL-37 and SOFA scores on the day of ICU admission of the patients with sepsis were found to be independent predictors of 28-day mortality, whereas IL-6 was not. The risk of mortality in patients with sepsis and high serum IL-37 concentration (≥107.05pg/ml) was 4.6 times that of patients with sepsis and low serum concentration. The AUC of IL-37 combined with SOFA-estimated 28-day mortality in patients with sepsis increased from 0.67 (p = 0.0022; 95% CI, 0.57-0.77) to 0.80 (p0.0001; 95% CI, 0.711-0.879). In addition, patients with sepsis and high serum IL-37 concentrations (≥107.05pg/ml) had poorer survival rate than those with low serum concentrations (107.05pg/ml).IL-37 concentrations at ICU admission are valuable for predicting the 28-day mortality risk of patients with sepsis, suggesting that IL-37 may be a novel biomarker. These findings can be used as a basis for guiding early clinical decision-making in treating patients with sepsis.

Hexagonal tantalum pentoxide (δ-Ta2O5) epitaxial films were successfully prepared on Y-stabilized ZrO2 (YSZ) (111) substrates by metalorganic chemical vapor deposition. The crystal structure and optical characteristics of the deposited films as a function of the substrate temperature were investigated. High quality stoichiometric single-crystalline δ-Ta2O5 film was gained at the optimum epitaxial growth temperature of 800 °C and the full-width at half-maximum of the ω rocking curve of δ-Ta2O5 (0001) was only 0.066°. The heteroepitaxial relationship between the δ-Ta2O5 film and YSZ (111) substrate was identified as δ-Ta2O5 (0001)‖YSZ (111) with δ-Ta2O5 [ 2 1 ¯ 1 ¯ 0 ‖YSZ [10 1 ‾ ] and was illustrated in a schematic diagram. This proposed film makes adequate preparations for developing a range of ultra wide band gap semiconductor devices.

Photovoltaic (PV) power generation has developed very rapidly worldwide in the recent years. There is a possibility that the PV power generation will switch from an auxiliary power supply, as of today, to a main power source in many power grids in the future. Naturally, dynamic studies on power grids with a high penetration of PV generators have become increasingly important, and thus have attracted major attentions from both the power industry and the academia. Consequently, dynamic modeling of PV generators has been investigated widely. However, among various proposed models, there is a confusion on the model applicability and a lack of the clarification on the required level of details on the modeling work, which severely limit the real industrial applications of the developed models. This paper reviews the state-of-the-art PV generator dynamic modeling work, with a focus on the modeling principles of PV generator for the power system dynamic studies. The paper presents the detailed modeling process for the recommended PV generator dynamic model, and clarifies the assumptions and simplifications made in the modeling process, thus raises the discussion on the model applicability. Studies that require further attentions on developing the dynamic models of PV generators for power system dynamic studies are identified and presented in the paper. However, this work does not intend to conclude the research work in this important field, instead, it aims to provoke more discussions on developing guidelines on building or selecting the appropriate models to fit into the purpose of the targeted dynamic studies.

Y2O3−MgO nanocomposite is introduced for infrared transparent ceramics due to its superior optical and mechanical characteristics. However, severe optical scattering and unnecessary absorption in the near- and mid-infrared regions restrict the applications of this material. Here, a broad mid-infrared transparent Y2O3−MgO nanocomposite is achieved for the first time through low temperature sintering using an LiF additive. The influence of LiF is successfully demonstrated on the mid-infrared transparency of the as-sintered and post-annealed nanocomposites. Spectroscopic analysis are also performed, and primary absorption factors of the Y2O3−MgO transparent ceramics are revealed. This study is a step toward designing widely utilized transparent ceramics.

Background Sellar lesions with central diabetes insipidus have a wide range of causes, and diagnosis is relatively difficult. The indication and clinical value of biopsy are still controversial. Objective To describe the etiology, demographic characteristics, manifestations, laboratory tests and imaging findings of this disease and to explore the clinical value and safety of endoscopic transsphenoidal biopsy. Methods Retrospective analysis of 124 patients with sellar lesions and central diabetes insipidus who underwent endoscopic transsphenoidal biopsy at the Neurosurgery Department, Peking Union Medical College Hospital, from 2011 to 2019. Results The main etiology includes congenital diseases, inflammatory/infectious diseases and tumor diseases. The most common diseases were germ cell tumors, Langerhans cell histiocytosis, lymphocytic hypophysitis, and Rathke's cleft cysts. Except for the age at the time of biopsy of patients with tumor diseases, which was significantly lower than that of the other two, the other clinical manifestations of the three types of diseases were not significantly different. Among the 124 patients, biopsy was performed via an endoscopic transsphenoidal approach for 101 with intrasellarly available lesions or via an endoscopic extended transsphenoidal approach for 23 with intrasellarly unavailable lesions. 6 patients had central nervous system infections after surgery, and 3 had cerebrospinal fluid rhinorrhea, of which 2 were surgically repaired. These incidences were basically the same as those of classic surgery. 2 patients had worse visual acuity, 2 had worse visual field, and 2 had worse eye movement. Excepting one patient, all of whom have recovered after treatment. Conclusions Noninvasive examination is difficult for identifying the common causes of this type of disease. Endoscopic transsphenoidal biopsy is relatively safe and effective, helps doctors to select the best treatment for patients, and is worth promoting.

The increasing penetration level of plug-in electric vehicles (PEVs), as well as distributed generators (DGs), imposes significant challenges on power system planning. This work presents a coordinated approach for the planning of PEV charging facilities and DGs, including both the locations and the capacities, with the consideration of the transportation - power network couplings. First, the PEV charging demand is characterized by a temporal-SoC (State of Charge) analysis, and the DG generation uncertainties are modeled by K-means clustering using historical data. The M/M/s/N queuing model is used to formulate the dynamics of charging stations and then obtain the optimal station capacity, including the number of chargers and waiting spaces. Furthermore, the placement of charging stations is optimized by the Floyd Algorithm to minimize the total distance to obtain charging service. Finally, the sitting and sizing of DGs are optimized over multiple objectives, including active power losses, reactive power losses, and voltage deviation. The solution is evaluated through a case study of the IEEE 53-bus test feeder coupled with a 25-node transportation network. It is shown that the proposed solution enables the active and reactive power losses as well as the voltage deviation to be reduced by 37.6%, 44.3%, and 33.6%, respectively, after the optimal integration of PEV charging stations and DGs. The scalability and effectiveness of the solution are further validated in an IEEE 123-bus test feeder coupled with the same transportation network, and the result confirms the effectiveness and scalability of the proposed solution.

Rare earth elements (REEs) have been increasingly diffused to the environment due to their extensive use and application in industries, agriculture, and high-tech devices, which have been regarded as emerge pollutants. However, the study concerning REEs in urban soils is still limited. Therefore, the objectives of this study were to investigate the potential source and risk of REEs in urban environment. We analyzed the concentration and distribution of REEs in urban park soils, and performed a combination of micro geochemical method and random forest method to characterize the pollution sources of REEs. The results showed that the ΣREE concentrations in Beijing urban park soils ranged from 117.19 to 198.09 mg/kg. Spatial distribution indicated that the high concentrations of REEs were mainly concentrated in the west of Beijing near an industrial area. The geochemical parameters, micro spherules and random forest results confirmed the anthropogenic pollution sources from industry and traffic. Risk assessment showed that the average daily doses of total REEs for children and adults were far below the reference threshold with values of 0.08 and 0.02 µg/kg/day, respectively. Our study has exhibited that though the reconstruction of parks from abandoned industrial sites showed an accumulation of REEs, the health risk of REEs for human beings are negligible.

Multiple sclerosis (MS) is associated with different ocular disorders. This study aimed to investigate the retinal microvascular changes detected by optical coherence tomography angiography (OCTA) in eyes with MS with or without a history of optic neuritis (ON).A comprehensive literature search was conducted in the Web of Science, Embase, PubMed, and Cochrane Library databases on September 26, 2021 for articles focused on OCTA manifestations in the eyes of MS patients compared with healthy controls. RevMan Manager (v.5.4) and Stata (v.14.1) were used to analyze the main differences and publication risks. Weighted mean differences and 95% confidence intervals were calculated for continuous estimates. This study also included subgroup analysis between three groups: eyes with multiple sclerosis and with optic neuritis (MSON); eyes with multiple sclerosis and without optic neuritis (MSNON); and healthy controls.Thirteen studies with a total of 1803 eyes were identified, including 957 eyes with MS and 846 eyes of healthy controls. The vessel density of the MS eyes decreased significantly in most areas of the radial peripapillary capillary. A marked reduction in the macular superficial capillary plexus of MS eyes regardless of ON history was also confirmed.The results suggest that MS patients demonstrated significant retinal microvasculature impairment regardless of ON history, compared to healthy controls. Retinal vessel density attenuation detected by OCTA may serve as a reliable early marker of MS.

Gallium oxide (Ga2O3) films have been deposited on SrTiO3 (100) substrates by using the metal-organic chemical vapor deposition (MOCVD) method. Post-deposition annealing was performed at different temperatures. XRD θ-2θ scans displayed that the annealing at 1000 °C leaded to β phase Ga2O3 film with the best crystalline quality. Microstructural and chemical composition analyses revealed that this film was single crystal β-Ga2O3 with stoichiometric ratio. The epitaxial relationships were clearly determined as β-Ga2O3 (100) || SrTiO3 (100) with β-Ga2O3 [001] || SrTiO3 . All of the prepared Ga2O3 samples have average transmittances in the visible range of more than 70%.

As an emerging 2D conjugated material, graphitic carbon nitride (CN) has attracted great research attention as important catalytic medium for transforming solar energy. Nanostructure modulation of CN is an effective way to improve catalytic activities and has been extensively investigated, but remains challenging due to complex processes, time consuming or low yield. Here, taking advantage of recent discovered good solvents for CN, a nanoprecipitation approach using poor solvents is proposed for preparation of CN nanoparticles (CN NPs). With simple processes of CN dissolution and precipitation, we can quickly synthesize CN NPs (˜40 nm) with a yield of up to 50%, the highest one to the best of our knowledge. As an example of potential applications, the as-prepared CN NPs were applied to photocatalytic degradation of dyes with an evident boosted performance up to 2.5 times. This work would open a new way for batch preparation of nanostructured CN and pave its large-scale industrial applications.