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ObjectiveThis study aims to assess the effect of mindfulness intervention on negative emotions (anxiety and depression) and quality of life in malignant tumor patients.MethodsThe databases, including CNKI, VIP, Wanfang, Chinese Biomedical Literature Database disc (CBMdisc), PubMed, Embase, Cochrane Library, and Web of Science (WoS), were searched from inception to January 2024. Randomized controlled trials examining the effects of mindfulness intervention on negative emotions and quality of life in malignant tumor patients were selected. Meta-analysis was conducted using RevMan 5.1.ResultsA total of 11 studies involving 993 patients were included. Compared with usual care, mindfulness intervention effectively reduced anxiety [SMD = −0.81, 95% CI (−1.01, −0.60), p

The conventional TO-247-3 packages with single-sided cooling limit the thermal and electrical performances of discrete SiC MOSFET devices. In this paper, a double-sided cooling press-pack (PP) packaging approach for the discrete SiC MOSFET device is proposed to optimize its thermal and electrical performances. First, a double-sided cooling PP structure for the discrete SiC MOSFET devices is designed with a copper foam gate pin and an embedded fixture. Then, based on finite element simulations, the steady-state thermal and electrical performances of the discrete SiC MOSFET device with the double-sided cooling PP package are analyzed, and the parasitic inductance of the designed SiC MOSFET device is extracted by the ANSYS Q3D software. Finally, a prototype of the double-sided cooling PP SiC MOSFET device is fabricated, and test platforms are established to verify its performance. The research findings demonstrate that the designed double-sided cooling PP SiC MOSFET device can reduce thermal resistance and switching loss by 47.4 % and 42.3%, respectively.

Abstract Purpose The changes in the lower limb alignment were vitally important after high tibial osteotomy (HTO). Therefore, the purpose of present study was to analyze the characteristics of plantar pressure distribution after HTO, and to investigate the effect of plantar pressure distribution on postoperative limb alignment. Methods Between May 2020 and April 2021, varus knee patients undergoing HTO were evaluated in the present study. The peak pressure of plantar regions, medial-lateral pressure ratio (MLPR), foot progression angle (FTA), anteroposterior COP (AP-COP), lateral symmetry of COP (LS-COP), and the radiographic parameters were evaluated preoperatively and at the final follow-up. Compared among the slight valgus (SV), moderate valgus (MV) and large valgus (LV) groups at the final follow-up, the peak pressure of HM, HC and M5 regions, and the MLPR were compared; the Knee Injury and Osteoarthritis Outcome Score4 (KOOS4) including four subscales, and the American of orthopedic foot and ankle society (AOFAS) were evaluated. Results The WBL%, HKA and TPI angle changed significantly after HTO (P

Abstract Press‐pack insulated gate bipolar transistor modules (PP‐IGBTs) have been widely used in high‐voltage and high‐power‐density applications, such as high‐voltage direct‐current (HVDC) converters, because of their advantages of low thermal resistance, double side cooling, and short‐circuit failure mode. Package failure is one of the main reasons for IGBT module failure. Package condition monitoring is the key to realizing modules fault diagnosis, condition prediction, and intelligent operation and maintenance. At present, a variety of characteristic parameters, such as on voltage and junction temperature, are used in package condition monitoring. However, the characteristic parameters show different variation laws under different package degradation modes. Therefore, the relationship between package degradation modes and characteristic parameters is the key to realizing the condition monitoring, so as to improve the reliability of the power electronic system. In this paper, first, the package structure of a PP‐IGBT is analyzed. Second, the mechanisms of fretting wear degradation, gate‐oxide degradation, spring degradation, lid warping degradation, micro arcing degradation, short‐circuit failure, and open‐circuit failure are reviewed. The variation laws of characteristic parameters under each degradation and failure mode are then investigated. Finally, three difficult problems including characteristic parameter measurement, especially pressure monitoring, high‐sensitivity detection, and characterization and evaluation, are discussed and analyzed.

Knowledge payment is a new method of electronic learning that has developed in the era of social media. With the impact of the COVID-19 pandemic, the market for knowledge payment is rapidly expanding. Exploring the factors that influence users’ sustained willingness is beneficial for better communication between knowledge payment platforms and users, and for achieving a healthier and more sustainable development of the knowledge payment industry. The model of unsustainable usage behavior of knowledge payment users was constructed on the basis of expectation inconsistency theory, price equilibrium theory, and perceived value theory, using the “cognitive-emotional-behavioral” model framework of cognitive emotion theory. The data were collected from 348 users through a web-based questionnaire and analyzed using structural equation modeling. Findings show that expectation inconsistency, price equilibrium, and quality value, emotional value, and social value have significant effects on discontinuous use intentions. Discontinuous use intentions also significantly affect discontinuous use behavior.

Voltage stability region assessment is the key to ensuring the reliable operation of offshore wind farms However, the traditional analysis method, which treats the WFs as a PQ node and directly connected to the infinite power grid, fails to take the cable capacitance and the dynamics of the converter into account, resulting an inaccurate evaluation of voltage stability. The contribution of this paper is to propose a more accurate method for assessing the voltage stability of OWFs. Firstly, based on the equivalent circuit method, the point of common coupling (PCC) and internal voltage characterization models of OWF considering the cable capacitance parameters are derived. Then, the coupling interface between the dynamic of the converter and the voltage characteristics of the system is designed, and the transfer function of the power injection from the DC side of the converter to the voltage of the collector system is established, which fully reflects the OWF Pin→Udc→Id→Upcc→Pout transitive relationship. Finally, a voltage stability criterion based on dPw, out/dId&dUdc/dt direction discrimination is proposed, and the influence of cable parameters, output power, and grid impedance on the voltage stability margin is analyzed. The accuracy of the proposed method is verified based on the RT-LAB platform.

Owing to the advantages of short-circuit failure mode, double-sided heat dissipation, and low thermal resistance, press-pack insulated gate bipolar transistors (PP-IGBTs) are widely used in high-power-density applications, such as high-voltage direct-current converters. As the core device of large-capacity power equipment, the reliability of a PP-IGBT is directly related to the security of the power system. In recent years, a silver-sintered package has been proposed to improve the electro-thermal performance of PP-IGBTs. However, the long-term reliability of this package has not been proven. In response to this problem, 3300-V/50-A silver-sintered PP-IGBT (SPP-IGBT) modules are used in long-reliability research. First, electro-thermal-stress finite-element models of PP-IGBTs and SPP-IGBTs were proposed and the accuracy of models verified by experiments. Through a simulation comparison, the results show that under the rated operating conditions, the on-voltage and maximum temperature of SPP-IGBTs dropped by 9.3% and 3.7%, respectively. In addition, the temperature and stress of each component were reduced, among which the surface stress of the IGBT chip emitter dropped by as much as 24.7%. Subsequently, a power-cycle test platform was established, and three PP-IGBTs and three SPP-IGBTs were tested. Finally, the experimental results were compared and analyzed, and the reasons for the sharp increase of on-voltage and metal melt were explored. The results show that the silver-sintered package improves the electrical-thermal performance and long-term reliability of the module.

Liposomes are the most widely used nanocarrier platform for the delivery of therapeutic and diagnostic agents, and a number of liposomes have been approved for use in clinical practice. After systemic administration, most liposomes are cleared by macrophages in the mononuclear phagocyte system, such as the liver and bone marrow (BM). However, the majority of studies have focused on investigating the therapeutic results of liposomal drugs, and too few studies have evaluated the potential side effects of empty nanocarriers on the functions of macrophages in the mononuclear phagocyte system. Here, we evaluate the potential effects of empty liposomes on the functions of BM niche macrophages. Following liposome administration, we observed lipid droplet (LD) accumulation in cultured primary macrophages and BM niche macrophages. We found that these LD-accumulating macrophages, similar to foam cells, exhibited increased expression of inflammatory cytokines, such as IL-1β and IL-6. We further provided evidence that liposome deposition and degradation induced LD biogenesis on the endoplasmic reticulum membrane and subsequently disturbed endoplasmic reticulum homeostasis and activated the inositol-requiring transmembrane kinase/endoribonuclease 1α/NF-κB signaling pathway, which is responsible for the inflammatory activation of macrophages after liposome engulfment. Finally, we also showed the side effects of dysfunctional BM niche macrophages on hematopoiesis in mice, such as the promotion of myeloid-biased output and impairment of erythropoiesis. This study not only draws attention to the safety of liposomal drugs in clinical practice but also provides new directions for the design of lipid-based drug carriers in preclinical studies.

BackgroundRapid eye movement (REM) sleep behavior disorder (RBD) predicts cognitive decline in Parkinson’s disease (PD) patients without dementia. However, underlying mechanisms remain unknown. Accumulating studies suggest glutamatergic system dysregulation is associated.ObjectiveTo examine the effect of RBD on the rate of cognitive decline in PD patients and investigate whether plasma levels of the neuroexosomal vesicular glutamate transporter-1 (VGLUT-1) and excitatory amino acid transporter-2 (EAAT-2) are altered in PD patients with RBD.MethodsThis study included 157 newly diagnosed cognitive normal PD patients and 70 healthy controls (HCs). Based on one-night polysomnography recordings, the PD subjects were divided into PD with and without RBD (PD-RBD and PD-nRBD) groups. All participants received a complete clinical and neuropsychological evaluation at baseline. Plasma levels of neuroexosomal VGLUT-1 and EAAT-2 were measured by ELISA kits. After a 3-year follow-up, we evaluated baseline plasma levels of neuroexosomal glutamate transporters in each group as a predictor of cognitive decline using MoCA score changes over 3 years in regression models.ResultsPlasma levels of neuron-derived exosomal EAAT-2 and VGLUT-1 were significantly lower in PD patients than in HCs. Plasma levels of neuroexosomal EAAT-2 were significantly lower in PD-RBD than PD-nRBD group at baseline. At the 3-year follow-up, PD-RBD patients presented greater cognitive decline. Lower baseline blood neuroexosomal EAAT-2 predicted cognitive decline over 3 years in PD-RBD patients (β = 0.064, P = 0.003).ConclusionThese findings indicate that blood neuroexosomal EAAT-2 is associated with cognitive decline in PD with RBD.

ObjectiveThe present study was designed for the contrastive analysis of conservative and percutaneous kyphoplasty (PKP) on pain severity and recovery of injured vertebrae in elderly patients with acute symptomatic osteoporotic vertebral compression fracture (OVCF).MethodsA total of 60 elderly patients with acute symptomatic OVCF were divided into two groups according to different treatment protocols, with 30 patients in each group. Patients in the Con group received conservative treatment, while patients in the PKP group received percutaneous kyphoplasty treatment. Clinical evaluation included the visual analogue scale (VAS), the Dallas pain questionnaire, the vertebral body leading edge height, the Cobb angle of injured vertebrae, the MOS item short-form health survey (SF-36), the Barthel index, and the mini-mental state examination (MMSE).ResultsAt 3 days, 3 months, and 6 months post-treatment, the score of VAS and the Cobb angle of injured vertebrae in patients of the PKP group were all significantly lower than those in the Con group (P 0.05).ConclusionCompared with conservative treatment, PKP treatment of elderly patients with acute symptomatic OVCF provides rapid pain relief, restoration of damaged vertebral body height, correction of Cobb's angle, and improved quality of life.

Many studies highlight that host phylogeny and diet are the two main factors influencing the animal gut microbiota. However, the internal mechanisms driving the evolution of animal gut microbiota may be more complex and complicated than we previously realized. Here, based on a large-scale meta-analysis of animal gut microbiota (16 s RNA gene data from approximately 1,800 samples; 108 metagenomes) across a wide taxonomic range of hosts, from invertebrate to vertebrate, we found high similarity in the gut microbial community (high proportion of Gammaproteobacteria (Pseudomonas)) of invertebrate insects and vertebrate bamboo-eating pandas (giant panda and red panda), which might be associated their plant-eating behavior and the presence of oxygen in the intestinal tract. A Pseudomonas strain-level analysis using 108 metagenomes further revealed that the response to either host niches or selection by the host might further lead to host-specific strains (or sub-strains) among the different hosts congruent with their evolutionary history. In this study, we uncovered new insights into the current understanding of the evolution of animals and their gut microbiota.

Macrophages play pivotal roles in the maintenance of tissue homeostasis. However, the reactivation of macrophages toward proinflammatory states correlates with a plethora of inflammatory diseases, including atherosclerosis, obesity, neurodegeneration, and bone marrow (BM) failure syndromes. The lack of methods to reveal macrophage phenotype and function in vivo impedes the translational research of these diseases. Here, we found that proinflammatory macrophages accumulate intracellular lipid droplets (LDs) relative to resting or noninflammatory macrophages both in vitro and in vivo, indicating that LD accumulation serves as a structural biomarker for macrophage phenotyping. To realize the staining and imaging of macrophage LDs in vivo, we developed a fluorescent fatty acid analog-loaded poly(lactic-co-glycolic acid) nanoparticle to label macrophages in mice with high efficiency and specificity. Using these novel nanoparticles, we achieved in situ functional identification of single macrophages in BM, liver, lung, and adipose tissues under conditions of acute or chronic inflammation. Moreover, with this intravital imaging platform, we further realized in vivo phenotyping of individual macrophages in the calvarial BM of mice under systemic inflammation. In conclusion, we established an efficient in vivo LD labeling and imaging system for single macrophage phenotyping, which will aid in the development of diagnostics and therapeutic monitoring. Moreover, this method also provides new avenues for the study of lipid trafficking and dynamics in vivo.

ABSTRACT It is commonly understood that dietary nutrition will influence the composition and function of the animal gut microbiome. However, the transmission of organisms from the diet-source microbiome to the animal gut microbiome in the natural environment remains poorly understood, and elucidating this process may help in understanding the evolution of herbivores and plant defenses. Here, we investigated diet-source microbiome transmission across a range of herbivores (insects and mammals) living in both captive and wild environments. We discovered a host bias among cohabitating herbivores (leaf-eating insects and deer), where a significant portion of the herbivorous insect gut microbiome may originate from the diet, while in deer, only a tiny fraction of the gut microbiome is of dietary origin. We speculated that the putative difference in the oxygenation level in the host digestion systems would lead to these host biases in plant-source (diet) microbiome transmission due to the oxygenation living condition of the dietary plant’s symbiotic microbiome. IMPORTANCE We discovered a host bias among cohabitating herbivores (leaf-eating insects and deer), where a significant portion of the herbivorous insect gut microbiome may originate from the diet, while in deer, only a tiny fraction of the gut microbiome is of dietary origin. We speculated that the putative difference in the oxygenation level in the host digestion systems would lead to these host biases in plant-source (diet) microbiome transmission due to the oxygenation living condition of the dietary plant's symbiotic microbiome. This study shed new light on the coevolution of herbivory and plant defense.

Abstract The gut microbial composition and function are shaped by different factors (e.g., host diet and phylogeny). Gut microbes play an important role in host nutrition and development. The gut microbiome may be used to evaluate the host potential environmental adaptation. In this study, we focused on the coevolution of the gut microbiome of captive and translocated Père David's deer populations (Elaphurus davidianus; Chinese: Père David's deer). To address this, we used several different macro‐ and micro‐ecological approaches (landscape ecology, nutritional methods, microscopy, isotopic analysis, and metagenomics). In this long‐term study (2011–2014), we observed some dissimilarities in gut microbiome community and function between the captive and wild/translocated Dafeng Père David's deer populations. These differences might link microbiome composition with deer diet within a given season. The proportion of genes coding for putative enzymes (endoglucanase, beta‐glucosidase, and cellulose 1,4‐beta‐cellobiosidase) involved in cellulose digestion in the gut microbiome of the captive populations was higher than that of the translocated population, possibly because of the high proportion of cellulose, hemicellulose, and lignin in the plants most consumed by the captive populations. However, the two enzymes (natA and natB) involved in sodium transport system were enriched in the gut microbiome in translocated population, possibly because of their high salt diet (e.g., Spartina alterniflora). Thus, our results suggested that Père David's deer gut microorganisms potentially coevolved with host diet, and reflected the local adaptation of translocated population in the new environment (e.g., new dietary plants: Spartina alterniflora). A current problem for Père David's deer conservation is the saturation of captive populations. Given that the putative evolutionary adaptation of Père David's deer gut microbiome and its possible applications in conservation, the large area of wetlands along the Yellow Sea dominated by S. alterniflora might be the major translocation region in the future.

Animals have stable dominant gut microbiomes under similar diets. Similar diets can also lead to similar gut microbial communities within host species levels. Giant pandas (Ailuropoda melanoleuca) and red pandas (Ailurus fulgens) have had long-term and stable bamboo diets, and seem well adapted to this highly fibrous diet. When compared to the gut microbiomes of Père David's deer (Elaphurus davidianus), humans, cheetah (Acinonyx jubatus), black-backed jackal (Canis-mesomelas), and black bear (Ursus thibetanus), giant panda gut microbiomes have high variation in the abundance of Pseudomonadaceae and Clostridiaceae, and are somewhat unstable. This high instability and dissimilarity may reflect an unstable gut environment, perturbation or selective pressure because of their carnivorous gastrointestinal system. A short digestive tract, brief digestion time and fast intestinal peristalsis may result in higher oxygen concentrations that select for the growth of aerobes and facultative anaerobes in giant pandas. Potential selection of high proportion of Pseudomonadaceae in giant panda (GP-HP) and red panda gut microbiomes may arise because of their postulated ability to degrade secondary compounds (e.g., cyanide compounds and aromatic compounds). However, high proportion of Clostridiaceae (GP-HF) may focus on cellulose and hemicellulose digestion. Thus, GP-HP and GP-HF groups have high dissimilarity on the functional level. These findings show that long-term similarities in diet do not always lead to similar or stable gut microbial system within the same host species and that other factors can drive the selection of gut taxa.

The relationship between animal conservation and the animal gut microbiome is a hot topic in current microbial ecology research. Our group has recently revealed that the occurrence of diverse combinations of gut microbial compositions and functions (metagenomics) in Père David’s deer ( Elaphurus davidianus ) populations is likely to lead to increased evolutionary potential and resilience in response to environmental changes. Thus, considering the effects of diet on the gut microbiome and the importance of a stable gut microbial community to host health, we suggest that a transitional buffer period (with feeding on a regular diet and a diet from the translocation habitat) is needed before animal translocation. When the gut microbiome enters into relatively stable stages and adapts to the new diet from the translocation site, the time is suitable for translocation. Long-term monitoring of the gut microbiomes of translocated animals (by collecting fresh feces and carrying out next-generation sequencing) is still necessary after their translocation.

Since 2005, 12 captive pandas have been translocated into the wild. Of these, three were killed by conditional pathogen infections after release. Given that the gut microbiome is important to host health and environmental adaptation, increasing the “wildness” of the gut microbiomes of captive pandas might improve translocation success. Here, we analyzed the long-term monitoring data (16S MISEQ data about 700 samples) of two wild giant panda populations (Xiaoxiangling and Minshan Mountains populations), five GPS-collared translocated giant pandas (TPs), and their living environment (dietary bamboos and soils) in the Liziping Reserve, China. We found that panda gut microbiome composition shifted dramatically after translocation: in the captive panda gut microbiome, Enterobacteriaceae dominated, while in the wild panda gut microbiome, Pseudomonadaceae dominated. More “wild” gut microbes were identified in the wild and semi-wild translocated panda guts than in the panda guts prior to release. However, under the current translocation strategy, the semi-wild stage lasts only 2–3 months, which might not be long enough to establish a stable “wild” gut microbial community. The observed changes in the translocated panda gut microbial communities (i.e., the proportional increase in Pseudomonadaceae abundance) and metagenomic function (i.e., the higher proportion of essential amino acid metabolic activity) might reflect a putative evolutionary adaptation to the local environment at the translocation site. We suggest that candidate pandas live with their mothers in a fenced area at the translocation site for an additional year prior to release. This is also more similar to the typical life cycle of the local wild giant pandas. Keywords: Biodiversity, Giant panda, Small population, Wildness, Gut microbes, Translocation

Press-pack insulated gate bipolar transistor (IGBT) device is the key component in the voltage source converter high voltage direct current (VSC-HVDC) due the advantage of the short-circuit failure. However, it is difficult to analyse the IGBT short-circuit failure mode due to the complex packaging and the short failure time. This study presents a method on simulation for the short-circuit failure mode of the press-pack IGBT device. First, based on the structure of a single-chip 3.3 kV/50 A press-pack IGBT, a multi-physical field model was presented by considering the electro–mechanical–thermal coupling effects, so that the internal weak layer was found by comparing with the different sustained pressures. Then, an equivalent method is proposed by using the different aluminium–silicon reaction osmotic hole in the chip, and the models were presented to simulate the short-circuit failure. Furthermore, after short-circuit failure of the device, the thermal resistance variation of each later in press-pack IGBT device was obtained. Finally, the experiment on the steady state and the short-circuit tests were performed, by analysing the weak layer and the short-circuit failure position of the IGBT device, the proposed models and analysis were testified. The achievement is helpful to optimal design of the press-pack IGBT device to improve the VSC-HVDC converter reliability.

ABSTRACT Gut microbes can enhance the ability of hosts to consume secondary plant compounds and, therefore, expand the dietary niche breadth of mammalian herbivores. The giant and red pandas are bamboo-eating specialists within the mammalian order Carnivora. Bamboo contains abundant plant secondary metabolites (e.g., cyanide-containing compounds). However, Carnivora species, including the giant panda, have deficient levels of rhodanese (one of the essential cyanide detoxification enzymes) in their tissues compared with the same tissues of herbivores. Here, we make a comparative analysis of 94 gut metagenomes, including 25 from bamboo-eating pandas (19 from giant pandas and 6 from red pandas), 30 from Père David’s deer, and 39 from published data for other mammals. The bamboo-eating pandas’ gut microbiomes had some common features, such as high proportions of Pseudomonas bacteria. The results revealed that bamboo-eating pandas’ gut microbiomes were significantly enriched in putative genes coding for enzymes related to cyanide degradation (e.g., rhodanese) compared with the gut microbiomes of typical herbivorous mammals, which might have coevolved with their special bamboo diets. The enrichment of putative cyanide-digesting gut microbes, in combination with adaptations related to morphology (e.g., pseudothumbs) and genomic signatures, show that the giant panda and red panda have evolved some common traits to adapt to their bamboo diet. IMPORTANCE The giant panda (Ailuropoda melanoleuca) and red panda (Ailurus fulgens), two obligate bamboo feeders, have distinct phylogenetic positions in the order Carnivora. Bamboo is extraordinarily rich in plant secondary metabolites, such as allied phenolic and polyphenolic compounds and even toxic cyanide compounds. Here, the enrichment of putative cyanide-digesting gut microbes, in combination with adaptations related to morphology (e.g., pseudothumbs) and genomic signatures, show that the giant panda and red panda have evolved some common traits to adapt to their bamboo diet. Thus, here is another story of diet-driven gut microbiota in nature.

Bone marrow mesenchymal stem cells (BMSCs) are used as a great promising choice for the treatment of cerebral ischemia. Herein, we discuss the neuroprotective effects of the combination of BMSCs transplantation and mild hypothermia (MH) in an ischemia-reperfusion rat model. First, BMSCs were isolated using density gradient centrifugation and the adherent screening method, followed by culture, identification and labeling with DAPI. Second, adult male SD rats were divided into 5 groups: sham group (surgery without blockage of middle cerebral artery), model group (middle cerebral artery occlusion (MCAO) was established 2h prior to reperfusion), BMSCs group (injection of BMSCs via the lateral ventricle 24h after MCAO), MH group (mild hypothermia for 3h immediately after MCAO) and combination therapy group (combination of BMSCs and MH). Finally, the modified neurological severity score (mNSS) test was performed to assess behavioral function at different time points (before MCAO, before transplantation, at day 1, day 5 and day 10 after transplantation). After that, the brain was subjected to TTC staining, and the homing and angiogenesis were evaluated by immumofluorescence and immunohistochemistry. Immunofluorescence staining and Western Blot analysis were performed to calculate the percentage of the infarct area and explore glial fibrillary acidic protein (GFAP) and vascular endothelial growth factor (VEGF). Our results showed that the combination therapy significantly decreased mNSS scores (P

Silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) have the advantages of high-frequency switching capability and the capability to withstand high temperatures, which are suitable for switching devices in a direct current (DC) solid state circuit breaker (SSCB). To guarantee fast and reliable action of a 400 V DC SSCB with SiC MOSFET, circuit design and prototype development were carried out. Taking 400V DC microgrid as research background, firstly, the topology of DC SSCB with SiC MOSFET was introduced. Then, the drive circuit of SiC MOSFET, fault detection circuit, energy absorption circuit, and snubber circuit of the SSCB were designed and analyzed. Lastly, a prototype of the DC SSCB with SiC MOSFET was developed, tested, and compared with the SSCB with Silicon (Si) insulated gate bipolar transistor (IGBT). Experimental results show that the designed circuits of SSCB with SiC MOSFET are valid. Also, the developed miniature DC SSCB with the SiC MOSFET exhibits faster reaction to the fault and can reduce short circuit time and fault current in contrast with the SSCB with Si IGBT. Hence, the proposed SSCB can better meet the requirements of DC microgrid protection.

Developing electrocatalysts with high activity and selectivity for the oxygen reduction reaction (ORR) is vital to promote the performance of the next-generation energy technologies, which depend on the efficiency of the catalytic reduction of dioxygen. In the structure of cytochrome c oxidases (CcOs), a histidine imidazole residue binding to the axial position of Fe plays a crucial role in facilitating the selective reduction of O2 to water. Inspired by nature, we herein report on the synthesis of CoIII corrole 1 tethered with an imidazole ligand as well as its electrocatalytic ORR and O2 binding features. As compared to the imidazolium-free analogue, complex 1 displayed remarkably boosted activity for the selective four-electron/four-proton (4e-/4H+) ORR with a half-wave potential of E1/2 = 0.82 V versus reversible hydrogen electrode (RHE) in 0.1 mol/L KOH solutions. Importantly, we demonstrate that the tethered axial imidazole ligand improves the O2 binding ability of 1 thermodynamically and dynamically, which is crucial to boost electrocatalytic ORR performance. This work presents an example to improve electrocatalytic ORR activity and selectivity of Co corroles by introducing an axial imidazole ligand to enhance the O2 binding and activation. [ABSTRACT FROM AUTHOR]