For electrocatalytic water splitting, the sluggish anodic oxygen evolution reaction (OER) restricts the cathodic hydrogen evolution reaction (HER). Therefore, developing an alternative anodic ...reaction with accelerating kinetics to produce value‐added chemicals, especially coupled with HER, is of great importance. Now, a thermodynamically more favorable primary amine (−CH2−NH2) electrooxidation catalyzed by NiSe nanorod arrays in water is reported to replace OER for enhancing HER. The increased H2 production can be obtained at cathode; meanwhile, a variety of aromatic and aliphatic primary amines are selectively electrooxidized to nitriles with good yields at the anode. Mechanistic investigations suggest that NiII/NiIII may serve as the redox active species for the primary amines transformation. Hydrophobic nitrile products can readily escape from aqueous electrolyte/electrode interface, avoiding the deactivation of the catalyst and thus contributing to continuous gram‐scale synthesis.
Substitution, higher efficiency: Hydrogen (H2) production is achieved at lower potential by replacing the OER with the electrooxidation of primary amines in water. The hydrophilic primary amines at the NiSe anode can be converted oxidant‐free into the corresponding hydrophobic nitriles with high yields (>93 %) and selectivity. The process is easily scalable and free of organic solvent, and the product easily isolable.
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The coronavirus disease (COVID-19) outbreak in December has seen more than 76,000 cases in China, causing more than 3,000 medical staff infections. As the disease is highly contagious, can be fatal ...in severe cases, and there are no specific medicines, it poses a huge threat to the life and health of nurses, leading to a severe impact on their emotional responses and coping strategies. Therefore, this study will investigate nurses' emotional responses and coping styles, and conduct a comparative study with nursing college students. This study was conducted through the online survey 'questionnaire star' from February 1st to February 20th, 2020 in Anhui Province, using the snowball sampling method to invite subjects. The results found that women showed more severe anxiety and fear than men. Participants from cities exhibited these symptoms more than participants from rural areas, however rural participants experienced more sadness than urban participants. The nearer a COVID-19 zone is to the participants, the stronger the anxiety and anger. The COVID-19 outbreak has placed immense pressure on hospitals and those nurses at the frontline are more seriously affected. Hospitals should focus on providing psychological support to nurses and training in coping strategies.
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Designing and fabrication of highly active single-atom catalysts (SACs) with maximized atomic efficiency is highly desirable but still remains a great challenge. Herein, highly active and stable ...cobalt single-atoms with a Co–N 4 moiety were uniformly anchored on a porous porphyrinic triazine-based framework (CoSAs/PTF) by a simple ionothermal method. Due to the abundant single-atom Co–N 4 species, the hierarchical porous structure and the good conductivity, the resultant catalyst is highly active for the electrocatalytic oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER). For the ORR, a more positive half-wave potential of 0.808 V ( vs. RHE) was achieved, compared with commercial benchmark Pt/C (0.806 V). Furthermore, a small onset potential of 21 mV and a low Tafel slope of 50 mV per decade were obtained for the HER. The porphyrin-like structure was found to stabilize the CoSAs effectively, thus leading to long-term durability and a remarkable methanol-tolerant behavior. This bifunctional single-atom catalyst might be a promising candidate to replace Pt-based electrocatalysts in electrolysers and fuel cells.
Newborn microglia rapidly replenish the whole brain after selective elimination of most microglia (>99%) in adult mice. Previous studies reported that repopulated microglia were largely derived from ...microglial progenitor cells expressing nestin in the brain. However, the origin of these repopulated microglia has been hotly debated. In this study, we investigated the origin of repopulated microglia by a series of fate-mapping approaches. We first excluded the blood origin of repopulated microglia via parabiosis. With different transgenic mouse lines, we then demonstrated that all repopulated microglia were derived from the proliferation of the few surviving microglia (<1%). Despite a transient pattern of nestin expression in newly forming microglia, none of repopulated microglia were derived from nestin-positive non-microglial cells. In summary, we conclude that repopulated microglia are solely derived from residual microglia rather than de novo progenitors, suggesting the absence of microglial progenitor cells in the adult brain.
Rechargeable aqueous Zn‐ion batteries (ZIBs) are regarded as one of the most promising devices for the next‐generation energy storage system. However, the uncontrolled dendrite growth on Zn metal ...anodes and the side hydrogen evolution reaction, which has not yet been well considered, hinder the practical application of these batteries. Herein, a uniform and robust metallic Sb protective layer is designed based on the theoretic calculation and decorated on Zn plate via in situ replacement reaction. Compared with the bare Zn plate, the as‐prepared Zn@Sb electrode provides abundant zincophilic sites for Zn nucleation, and homogenizes the electric field around the Zn anode surface, both of which promote the uniform Zn deposition to achieve a dendrite‐free morphology. Moreover, the Gibbs free energy (∆GH) calculation and in situ characterization demonstrate that hydrogen evolution reaction can be effectively suppressed by the Sb layer. Consequently, Sb‐modified Zn anodes exhibit an ultralow voltage hysteresis of 34 mV and achieve excellent cycling stability over 1000 h with hydrogen‐ and dendrite‐free behaviors. This work provides a facile and effective strategy to suppress both hydrogen evolution reaction and dendrite growth.
A uniform and robust metallic Sb protective layer is decorated on Zn plate via in situ replacement reaction. With rich zincophilic sites for Zn nucleation, improved electrolyte wettability and homogenized electric field, the Sb layer promotes the uniform Zn deposition with a dendrite‐free morphology. Moreover, the Gibbs free energy calculation and in situ characterization demonstrate that hydrogen evolution reaction can be effectively suppressed by the Sb layer.
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Global precipitation is becoming increasingly intense due to the extreme climate. Therefore, creating new technology to manage water resources is crucial. To create a sustainable urban and ecological ...environment, a water level and water quality control system implementing artificial intelligence is presented in this research. The proposed smart monitoring system consists of four sensors (two different liquid level sensors, a turbidity and pH sensor, and a water oxygen sensor), a control module (an MCU, a motor, a pump, and a drain), and a power and communication system (a solar panel, a battery, and a wireless communication module). The system focuses on low-cost Internet of Things (IoT) devices along with low power consumption and high precision. This proposal collects rainfall from the preceding 10 years in the application region as well as the region’s meteorological bureau’s weekly weather report and uses artificial intelligence to compute the appropriate water level. More importantly, the adoption of dynamic adjustment systems can reserve and modify water resources in the application region more efficiently. Compared to existing technologies, the measurement approach utilized in this study not only achieves cost savings exceeding 60% but also enhances water level measurement accuracy by over 15% through the successful implementation of water level calibration decisions utilizing multiple distinct sensors. Of greater significance, the dynamic adjustment systems proposed in this research offer the potential for conserving water resources by more than 15% in an effective manner. As a result, the adoption of this technology may efficiently reserve and distribute water resources for smart cities as well as reduce substantial losses caused by anomalous water resources, such as floods, droughts, and ecological concerns.
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We present the first example of charged imidazolium functionalized porphyrin‐based covalent organic framework (Co‐iBFBim‐COF‐X) for electrocatalytic CO2 reduction reaction, where the free anions ...(e.g., F−, Cl−, Br−, and I−) of imidazolium ions nearby the active Co sites can stabilize the key intermediate *COOH and inhibit hydrogen evolution reaction. Thus, Co‐iBFBim‐COF‐X exhibits higher activity than the neutral Co‐BFBim‐COF, following the trend of F−<Cl−<Br−<I−. Particularly, the Co‐iBFBim‐COF‐I− showed nearly 100 % CO2 selectivity at a low full‐cell voltage of 2.3 V, and achieved a high CO2 partial current density of 52 mA cm−2 with a turnover frequency of 3018 h−1 at 2.4 V in the anion membrane electrode assembly, which is 3.57 times larger than that of neutral Co‐BFBim‐COF. This work provides new insight into the importance of free anions in the stabilization of intermediates and decreasing the local binding energy of H2O with active moiety to enhance CO2 reduction reaction.
Charged imidazolium struts were integrated into two‐dimensional cobalt porphyrin‐based covalent organic frameworks (Co‐iBFBim‐COF‐X) creating catalytic pockets with 5,10,15,20‐tetrakis(4‐aminophenyl)‐porphinatocobalt centers and halogen counter ions (e.g., F−, Cl−, Br−, and I−). The free imidazolium anions in the proximity of the active Co sites in the Co‐iBFBim‐COF‐X can stabilize the key intermediate *COOH and inhibit the occurrence of HER through hydrogen bonding.
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We propose an effective highest occupied d‐orbital modulation strategy engendered by breaking the coordination symmetry of sites in the atomically precise Cu nanocluster (NC) to switch the product of ...CO2 electroreduction from HCOOH/CO to higher‐valued hydrocarbons. An atomically well‐defined Cu6 NC with symmetry‐broken Cu−S2N1 active sites (named Cu6(MBD)6, MBD=2‐mercaptobenzimidazole) was designed and synthesized by a judicious choice of ligand containing both S and N coordination atoms. Different from the previously reported high HCOOH selectivity of Cu NCs with Cu−S3 sites, the Cu6(MBD)6 with Cu−S2N1 coordination structure shows a high Faradaic efficiency toward hydrocarbons of 65.5 % at −1.4 V versus the reversible hydrogen electrode (including 42.5 % CH4 and 23 % C2H4), with the hydrocarbons partial current density of −183.4 mA cm−2. Theoretical calculations reveal that the symmetry‐broken Cu−S2N1 sites can rearrange the Cu 3d orbitals with
dx2-y2
${d_{x^2 - y^2 } }$
as the highest occupied d‐orbital, thus favoring the generation of key intermediate *COOH instead of *OCHO to favor *CO formation, followed by hydrogenation and/or C−C coupling to produce hydrocarbons. This is the first attempt to regulate the coordination mode of Cu atom in Cu NCs for hydrocarbons generation, and provides new inspiration for designing atomically precise NCs for efficient CO2RR towards highly‐valued products.
Breaking the coordination symmetry of Cu site in atomically precise Cu6 cluster forms Cu‐S2N1 site, which rank the dx2‐y2 orbital as the highest occupied d orbital to favor the specific coordination between C atom of CO2 and Cu−S2N1 site. This binding mode is conductive to the generation of *COOH instead of *OCHO, thereby switching the product of electrocatalytic CO2 reduction reaction to higher‐valued hydrocarbons.
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Oral squamous cell carcinoma (OSCC) is a highly aggressive cancer and the fourth leading malignancy among males in Taiwan. Some pathogenic bacteria are associated with periodontitis and oral cancer. ...However, the comprehensive profile of the oral microbiome during the cancer's progression from the early stage to the late stage is still unclear. We profiled the oral microbiota and identified bacteria biomarkers associated with OSCC. The microbiota of an oral rinse from 51 healthy individuals and 197 OSCC patients at different stages were investigated using 16S rRNA V3V4 amplicon sequencing, followed by bioinformatics and statistical analyses. The oral microbiota communities from stage 4 patients showed significantly higher complexity than those from healthy controls. The populations also dynamically changed with the cancer's progression from stage 1 to stage 4. The predominant phyla in the oral samples showed variation in the relative abundance of
, and
. The abundance of
increased significantly with the progression of oral cancer from the healthy controls (2.98%) to OSCC stage 1 (4.35%) through stage 4 (7.92%). At the genus level, the abundance of
increased, while the number of
, and
decreased with cancer progression.
, and
were associated with OSCC, and they progressively increased in abundance from stage 1 to stage 4. The abundances of
, and
were inversely associated with OSCC progression. We selected a bacterial marker panel of three bacteria (upregulated
, down-regulated
, and
), which had an AUC of 0.956 (95% CI = 0.925-0.986) in discriminating OSCC stage 4 from the healthy controls. Furthermore, the functional prediction of oral bacterial communities showed that genes involved in carbohydrate-related metabolism, such as methane metabolism, and energy-metabolism-related parameters, such as oxidative phosphorylation and carbon fixation in photosynthetic organisms, were enriched in late-stage OSCC, while those responsible for amino acid metabolism, such as folate biosynthesis and valine, leucine, and isoleucine biosynthesis, were significantly associated with the healthy controls. In conclusion, our results provided evidence of oral bacteria community changes during oral cancer progression and suggested the possibility of using bacteria as OSCC diagnostic markers.
Possible association between diabetes mellitus (DM) and Alzheimer's disease (AD) has been controversial. This study used a nationwide population-based dataset to investigate the relationship between ...DM and subsequent AD incidence.
Data were collected from Taiwan's National Health Insurance Research Database, which released a cohort dataset of 1,000,000 randomly sampled people and confirmed it to be representative of the Taiwanese population. We identified 71,433 patients newly diagnosed with diabetes (age 58.74 ± 14.02 years) since January 1997. Using propensity score, we matched them with 71,311 non-diabetic subjects by time of enrollment, age, gender, hypertension, hyperlipidemia, and previous stroke history. All the patients were followed up to December 31, 2007. The endpoint of the study was occurrence of AD.
Over a maximum 11 years of follow-up, diabetic patients experienced a higher incidence of AD than non-diabetic subjects (0.48% vs. 0.37%, p<0.001). After Cox proportional hazard regression model analysis, DM (hazard ratio HR, 1.76; 95% confidence interval CI, 1.50-2.07, p<0.001), age (HR, 1.11; 95% CI, 1.10-1.12, p<0.001), female gender (HR, 1.24; 95% CI, 1.06-1.46, p=0.008), hypertension (HR, 1.30; 95% CI, 1.07-1.59, p=0.01), previous stroke history (HR, 1.79; 95% CI, 1.28-2.50, p<0.001), and urbanization status (metropolis, HR, 1.32; 95% CI, 1.07-1.63, p=0.009) were independently associated with the increased risk of AD. Neither monotherapy nor combination therapy with oral antidiabetic medications were associated with the risk of AD after adjusting for underlying risk factors and the duration of DM since diagnosis. However, combination therapy with insulin was found to be associated with greater risk of AD (HR, 2.17; 95% CI, 1.04-4.52, p=0.039).
Newly diagnosed DM was associated with increased risk of AD. Use of hypoglycemic agents did not ameliorate the risk.
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