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The detection of a fallen person (FPD) is a crucial task in guaranteeing individual safety. Although deep-learning models have shown potential in addressing this challenge, they face several obstacles, such as the inadequate utilization of global contextual information, poor feature extraction, and substantial computational requirements. These limitations have led to low detection accuracy, poor generalization, and slow inference speeds. To overcome these challenges, the present study proposed a new lightweight detection model named Global and Local You-Only-Look-Once Lite (GL-YOLO-Lite), which integrates both global and local contextual information by incorporating transformer and attention modules into the popular object-detection framework YOLOv5. Specifically, a stem module replaced the original inefficient focus module, and rep modules with re-parameterization technology were introduced. Furthermore, a lightweight detection head was developed to reduce the number of redundant channels in the model. Finally, we constructed a large-scale, well-formatted FPD dataset (FPDD). The proposed model employed a binary cross-entropy (BCE) function to calculate the classification and confidence losses. An experimental evaluation of the FPDD and Pascal VOC dataset demonstrated that GL-YOLO-Lite outperformed other state-of-the-art models with significant margins, achieving 2.4-18.9 mean average precision (mAP) on FPDD and 1.8-23.3 on the Pascal VOC dataset. Moreover, GL-YOLO-Lite maintained a real-time processing speed of 56.82 frames per second (FPS) on a Titan Xp and 16.45 FPS on a HiSilicon Kirin 980, demonstrating its effectiveness in real-world scenarios.
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Background: Exposure to particulate matter (PM) has been a major public health threat, but the potentially differential effects on asthma of PM remain largely unknown in high altitude settings. We evaluated the effects of ambient PM on asthma in high altitude settings. Methods: The study recruited a representative sample from high altitude settings using a multistage stratified sampling procedure. Asthma was defined by a self-reported history of diagnosis by a physician or by wheezing symptoms in the preceding 12 months. The annual mean PM2.5 and PM10 concentrations were calculated for each grid cell at 1-km spatial resolution based on the geographical coordinates. Results: We analyzed data for participants (mean age 39.1 years, 51.4% female) and 183 (3.7%, 95% confidence interval (CI): 3.2-4.2) of the participants had asthma. Prevalence was higher in women (4.3%, 95% CI 3.5-5.1) than in men (3.1%, 2.4-3.8) and increasing with higher concentration of PM exposures. For an interquartile range (IQR) difference (8.77 µg/m3) in PM2.5 exposure, the adjusted odds ratio (OR) was 1.64 (95% CI 1.46-1.83, P < 0.001) for risk of asthma. For PM10, there was evidence for an association with risk of asthma (OR 2.34, 95% CI: 1.75-3.15, P < 0.001 per IQR of 43.26 µg/m3). Further analyses showed that household mold or damp exposure may aggravate PM exposure associated risks of asthma. Conclusions: This study identified that PM exposure could be a dominate environmental risk factor for asthma but largely unconsidered in the high-altitude areas. The association between PM exposure and asthma should be of interest for planners of national policies and encourage programs for prevention of asthma in residents living at high altitudes.
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Objective: Chronic subdural hematoma (CSDH) is a common disease in neurosurgery, which usually occurs in the elderly. Seizure is one of the postoperative complications in CSDH patients and can affect patient outcomes. There is currently no consensus on whether antiepileptic drugs should be prescribed prophylactically. The aim of this study was to evaluate independent risk factors for postoperative seizures and unfavorable outcomes in CSDH patients. Methods: We reviewed 1,244 CSDH patients who had undergone burr-hole craniotomy in this study. Patient clinical data, CT scan results, recurrence and outcome data were collected. We divided the patients into two groups based on whether they had a postoperative seizure. Percentages and χ2 tests were applied for categorical variables. Standard deviations and two-sided unpaired t-tests were applied for continuous variables. Stepwise logistic regression analyses were performed to identify the independent factors of postoperative seizures and unfavorable outcomes. Results: The incidence of seizures after CSDH surgery was 4.2% in this study. There was no significant difference in recurrence rate between seizure and non-seizure patients (p = 0.948), and the outcome of seizure patients was significantly poor (p < 0.001). There are more postoperative complications in seizure patients (p < 0.001). Logistic regression analysis showed that the independent risk factors for postoperative seizures included drinking history (p = 0.031), cardiac disease (p = 0.037), brain infarction (p = 0.001) and trabecular hematoma (p < 0.001). The use of urokinase is a protective factor for postoperative seizures (p = 0.028). Hypertension is an independent risk factor for unfavorable outcome in seizure patients (p = 0.038). Conclusion: Seizures after CSDH surgery were associated with postoperative complications, higher mortality and poorer clinical outcomes at follow-up. We believe that alcohol consumption, cardiac disease, brain infarction and trabecular hematoma are independent risk factors for seizures. The use of urokinase is a protective factor against seizures. Patients with postoperative seizures need more stringent management of their blood pressure. A prospective randomized study is necessary to determine which subgroups of CSDH patients would benefit from antiepileptic drugs prophylaxis.
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Cycling has always been popular in China, especially during the years when the government encouraged green travel. Many people participate in rides to ease traffic congestion and increase transfer convenience. Due to the disorganized and tidal nature of cycling, cyclists create many conflicts with other groups. Adolescents are vulnerable road users with a strong curiosity and risk-taking mindset. Identifying the factors influencing adolescents' aggressive riding behavior can assist in developing strategies to prevent this behavior. An online questionnaire was used to collect data on bicycling among students in a middle school in Guangzhou, China. The theory of planned behavior (TPB) and prototype willingness model (PWM) have been applied to study travel behavior and adolescent risk behavior. To investigate the impact of psychological variables on adolescent aggressive behavior, we used TPB, PWM, TPB + PWM, and an integrated model. Behavioral intentions are greatly influenced by attitudes, subjective norms, and perceived behavioral control. Both descriptive and moral norms played a role in behavioral willingness. The integrated model explained 18.3% more behavioral variance than the TPB model. The social reactive pathway explained more variance in behavior than the rational path.
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The purpose of this study was to compare neuroendoscopy-assisted burr-hole evacuation with conventional burr-hole evacuation in the treatment of chronic subdural hematoma (CSDH), and to evaluate the curative effect of neuroendoscopy. This study follows PRISMA guidelines and uses the keywords "chronic subdural hematoma," "neuroendoscopies," "neuroendoscopy," "endoscopy," "endoscopic neurosurgery," and "neuroendoscopic surgery" to conduct an electronic search of online databases, including PubMed, Embase, Web of Science, and Cochrane Library. There were no restrictions on language or publication year. This meta-analysis involved 948 patients in six studies. The results showed that the recurrence rate in the neuroendoscopy group was significantly lower than that in the conventional burr-hole group (3.1% vs. 13.8%, P<0.001). Compared with the control group, the neuroendoscopy group had a longer operation time (P<0.001) and a shorter postoperative drainage time (P<0.001). In addition, there was no significant difference in hospital stay (P=0.14), mortality (P=0.39), postoperative morbidity (P=0.12), or 6-month neurological outcomes (P=0.32) between the two groups. It should be noted that the comparison of neurological outcomes was based on 269 patients (6/106 vs. 14/163). Compared with conventional burr-hole evacuation, neuroendoscopy-assisted burr-hole evacuation reduces the recurrence rate of CSDH and shortens the postoperative drainage time. However, the neuroendoscopy group did not have lower mortality or morbidity or better functional outcomes. In the future, randomized controlled trials are needed to further evaluate the efficacy and safety of neuroendoscopic surgery.
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Hematoma Subdural Crônico , Neuroendoscopia , Humanos , Hematoma Subdural Crônico/cirurgia , Hematoma Subdural Crônico/etiologia , Trepanação/métodos , Procedimentos Neurocirúrgicos/métodos , Drenagem/efeitos adversos , Recidiva , Resultado do Tratamento , Estudos RetrospectivosRESUMO
Background: The geriatric nutritional risk index (GNRI) is a simple index for evaluating the nutrition status of elderly patients. Many investigations have demonstrated that this index is associated with the prognosis of several diseases. This study aims to identify the relationship between the GNRI and recovery in elderly mild traumatic brain injury (mTBI) patients. Methods: A total of 228 mTBI patients older than 65 years were included in this study. mTBI was defined as an injury to the brain with a loss of consciousness of 30 min or less, a duration of posttraumatic amnesia of <24 h, and an admission Glasgow Coma Scale (GCS) score of 13-15. The Glasgow Outcome Scale Extended (GOSE), an outcome scale assessing functional independence, work, social activities, and personal relationships, was applied to assess the recovery of the patients. The clinical outcome was divided into complete recovery (GOSE = 8) and incomplete recovery (GOSE ≤ 7) at 6 months after the injury. Multivariate logistic regression was applied to evaluate the association between the GNRI and recovery of elderly mTBI patients, with adjustment for age, sex, hypertension, diabetes, and other important factors. Results: The receiver operating curve (ROC) analysis demonstrated that the cutoff value of GNRI was 97.85, and the area under the curve (AUC) was 0.860. Compared to the patients with a high GNRI, the patients with a low GNRI were older, had a higher prevalence of anemia, acute subdural hematoma, and subarachnoid hemorrhage, had a higher age-adjusted Charlson Comorbidity Index value, and had lower levels of albumin, lymphocytes, and hemoglobin. Multivariable analysis showed that high GNRI was associated with a lower risk of 6-month incomplete recovery (OR, 0.770, 95% CI: 0.709-0.837, p < 0.001). Conclusion: The GNRI has utility as part of the objective risk assessment of incomplete 6-month functional recovery in elderly patients with mTBI.
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BACKGROUND: Chronic subdural hematomas (CSDHs) are one of the most common neurosurgical conditions. The standard surgical technique includes burr-hole craniostomy, followed by intraoperative irrigation and placement of subdural closed-system drainage. The drainage is generally removed after 48 h, which can be described as fixed-time drainage strategy. According to literature, the recurrence rate is 5-33% with this strategy. In our retrospective study, postoperative hematoma volume was found to significantly increase the risk of recurrence. Based on these results, an exhaustive drainage strategy is conducted to minimize postoperative hematoma volume and achieve a low recurrence rate and good outcomes. METHODS: This is a prospective, multicenter, open-label, blinded endpoint randomized controlled trial designed to include 304 participants over the age of 18-90 years presenting with a symptomatic CSDH verified on cranial computed tomography or magnetic resonance imaging. Participants will be randomly allocated to perform exhaustive drainage (treatment group) or fixed-time drainage (control group) after a one-burr hole craniostomy. The primary endpoint will be recurrence indicating a reoperation within 6 months. DISCUSSION: This study will validate the effect and safety of exhaustive drainage after one-burr hole craniostomy in reducing recurrence rates and provide critical information to improve CSDH surgical management. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04573387. Registered on October 5, 2020.
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Hematoma Subdural Crônico , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Prospectivos , Hematoma Subdural Crônico/diagnóstico por imagem , Hematoma Subdural Crônico/cirurgia , Recidiva , Drenagem/efeitos adversos , Drenagem/métodos , Resultado do Tratamento , Craniotomia/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como AssuntoRESUMO
BACKGROUND: Some peripheral blood markers have been demonstrated to be correlated with the re-formation of chronic subdural hematoma (CSDH). The aim of this study was to identify the correlation between nutritional/inflammatory peripheral blood markers and CSDH. METHODS: 188 CSDH patients and 188 age-matched healthy controls were included in this research. The clinical characteristics and peripheral blood markers associated with nutritional or inflammatory status were obtained and analyzed. Conditional logistic regression analysis was applied to identify the potential CSDH risk factors. All the participants were divided into 3 groups based on the tertiles of change in risk factors. The Cochran-Armitage test and one way ANOVA were applied to identify the association between baseline characteristics and independent risk factors. Moreover, the net reclassification index (NRI) and integrated discrimination index (IDI) were calculated to evaluate the improvement in model performance after adding the independent risk factors in the conventional model. RESULTS: The logistic regression analysis demonstrated that the increased albumin (OR, 0.615; 95 %CI,0.489-0.773; P < 0.001) and lymphocyte count (OR, 0.141; 95 %CI,0.025-0.796; P = 0.027) were associated with lower risk of CSDH. Moreover, addition of albumin and lymphocyte to conventional risk factors significantly improved the risk prediction of CSDH(NRI: 46.47 %, P < 0.001; IDI: 30.92 %, P < 0.001; NRI: 22.45 %, P = 0.027; IDI: 1.23 %, P = 0.037, respectively) CONCLUSION: The decreased albumin and lymphocyte levels were correlated with a high risk of chronic subdural hematoma. The nutritional and inflammatory serum markers should be put great attention because these markers may play roles in finding the cause of CSDH and predicting its risk.
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Hematoma Subdural Crônico , Humanos , Estudos de Casos e Controles , Hematoma Subdural Crônico/etiologia , Medição de Risco , Fatores de Risco , Estudos Retrospectivos , AlbuminasRESUMO
China's economy has shifted from the stage of high-speed growth to the stage of high-quality development. This paper selects panel data of 30 provinces, municipalities directly under the Central Government and autonomous regions (except Tibet) in mainland China with the time dimension of 2006-2016, selects indicators from five dimensions of innovation, coordination, greenness, openness and sharing, uses principal component analysis to construct a system of indicators of high-quality economic development, and uses the spatial Durbin model to empirically the impact of government investment behavior in the three industries on the regional economic high-quality development was studied. The results show that: first, there is a significant positive spatial correlation between China's economic quality development. Second, government investment in different industries has different effects on the quality development of the economy. Investment in the tertiary industry can boost employment, raise income level, promote economic quality development, and enhance sharing, coordination and innovation; investment in the secondary industry can enhance innovation, but because of the "crowding-out effect", it will reduce openness and sharing, and is not conducive to promoting economic quality development; investment in the primary industry can Investment in the primary industry can significantly improve coordination, but it will reduce innovation, greenness, openness and sharing, which will also have a negative impact on the overall high-quality economic development. Third, there is a significant spatial spillover effect of government investment behavior on regional economic quality development, and the economic quality development of this region will have an impact on neighboring regions. Finally, based on the research results, this paper puts forward countermeasure suggestions for promoting high-quality economic development.
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Desenvolvimento Econômico , Indústrias , Governo , Cidades , ChinaRESUMO
Developing a convenient method to determine the complete structure of single-walled carbon nanotubes (SWNTs) is important to achieve the fully controlled growth of this nanomaterial. However, approaches that can identify handedness at the atomic level with simple equipment, operation, and data analysis are still lacking. Here, the SWNTs/graphene (Gr) vertical heterostructures are artificially constructed with aligned interfaces to realize the lattice interpretation of SWNT upper and lower walls separately by only one transmission electron microscopy image, thus transforming the 3D handedness information to projected 2D space. Gr displays prominent out-of-plane deformation at the interface, promoting the energetic advantage for the aligned interface construction. The interfacial alignment between the SWNT and Gr shows no obvious dependence on either the helical angle or diameter of SWNTs. The half-wrapping of SWNTs by deformed Gr also triggers diversified alterations in electronic structures based on theoretical calculations. 27 specimens with SWNTs prepared by two disparate methods are examined, implying equal handedness distribution in the randomly aligned SWNTs grown on quartz and potential handedness enrichment in horizontal SWNT arrays grown on a-sapphire. This work provides a simple strategy for chiral discrimination and lays a characterization foundation for handedness-selective growth of nanomaterials.
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Stacking two dimensional tunneling heterostructures has always been an important strategy to improve the optoelectronic device performance. However, there are still many disputes about the blocking ability of monolayer (1L-) h-BN on the interlayer coupling. Graphene/h-BN/MoS2 optoelectronic devices have been reported for superior device results. In this study, starting with graphene/h-BN/MoS2 heterostructures, we report experimental evidence of 1L-h-BN barrier layer modulation effects about the electronic band structures and exciton properties. We find that 1L-h-BN insertion only partially blocks the interlayer carrier transfer. In the meantime, the 1L-h-BN barrier layer weakens the interlayer coupling effect, by decreasing the efficient dielectric screening and releasing the quantum confinement. Consequently, the optical conductivity and plasmon excitation slightly improve, and the electronic band structures remain unchanged in graphene/h-BN/MoS2, explaining their fascinating optoelectronic responses. Moreover, the excitonic binding energies of graphene/h-BN/MoS2 redshift with respect to the graphene/MoS2 counterparts. Our results, as well as the broadband optical constants, will help better understand the h-BN barrier layers, facilitating the developing progress of h-BN-based tunneling optoelectronic devices.
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Dysregulation of neuronal development may cause neurodevelopmental disorders. However, how to regulate embryonic neuronal development and whether this regulation can be medical interrupted are largely unknown. This study aimed to investigate whether and how andrographolide (ANP) regulates embryonic neuronal development. The pregnant mice at embryonic day 10.5 (E10.5) were administrated with ANP, and the embryonic brains were harvested at E17.5 or E18.5. Immunofluorescence (IF), Immunohistochemistry (IHC) performed to determine whether ANP is critical in regulating neuronal development. Real-time quantitative PCR, western blotting, cell counting kit-8 assay, Flow Cytometry assay, Boyden Chamber Migration assay carried out to evaluate whether ANP regulates neuronal proliferation and migration. Protein-protein interaction, CO-immunoprecipitation and IF staining carried out to evaluate whether ANP regulates the interaction between PFKFB3, NeuN and TBR1. Knockdown or overexpression of PFKFB3 by adenovirus infection were used to determine whether ANP inhibits neuronal development through PFKFB3 mediated glycolytic pathway. Our data indicated that ANP inhibited the maturation of embryonic neurons characterized by suppressing neuronal proliferation and migration. ANP regulated the interaction between PFKFB3, NeuN, and TBR1. Knockdown of PFKFB3 aggravated ANP mediated inhibition of neuronal proliferation and migration, while overexpression of PFKFB3 attenuated ANP mediated neuronal developmental suppression. In summary, ANP suppressed the expression of PFKFB3, and interrupted the interaction between TRB1 and NeuN, resulting in suppressing neuronal proliferation, migration and maturation and eventually inhibiting murine embryonic neuronal development.
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Diterpenos , Fosfofrutoquinase-2 , Gravidez , Feminino , Camundongos , Animais , Fosfofrutoquinase-2/genética , Fosfofrutoquinase-2/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Diterpenos/farmacologia , Glicólise , Proliferação de CélulasRESUMO
We conducted a meta-analysis to analyze the effects of pneumocephalus after chronic subdural hematoma (CSDH) surgery on hematoma recurrence, mortality, and functional outcomes. In this meta-analysis, following PRISMA guidelines, PubMed, Embase, Cochrane Library, and Web of Science online databases were queried using the keywords "pneumocephalus," "pneumoencephalos," "intracranial pneumatocele," "pneumo encephalon," "subdural air," and "chronic subdural hematoma." The results were limited to English-language articles. Through the online database, we identified a total of 276 articles and finally included 14 articles for meta-analysis. The results showed that the recurrence rate in the pneumocephalus group was higher than that in the control group, with a pooled OR of 3.35 (CI: 2.51-4.46, P < 0.001). There was no difference in recurrence rate between the no/few and moderate pneumocephalus groups (OR: 1.27, CI: 0.68-2.37, P = 0.46), but the recurrence rate of the large pneumocephalus group was significantly higher than that of the moderate group, with a pooled OR of 3.29 (CI: 1.71-6.32, P < 0.001). This study failed to show higher mortality and worse outcomes in the pneumocephalus group than in the control. Pneumocephalus after surgical evacuation of CSDH was associated with the recurrence rate of hematoma. Pneumocephalus affecting recurrence was correlated with gas volume, and moderate pneumocephalus may have less impact, while patients with large pneumocephalus are more likely to recur than those with moderate pneumocephalus. More prospective cohort studies are needed for further investigation and verification. This meta-analysis was registered (PROSPERO CRD42022321800).
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Hematoma Subdural Crônico , Humanos , Hematoma Subdural Crônico/cirurgia , Estudos ProspectivosRESUMO
Carbon emissions trading policy has received widespread attention from scholars as a core policy tool to reduce carbon emissions. While most scholars have previously focused on the carbon emission reduction effect, this paper investigates the impact of carbon emissions trading policy on green technology innovation using a differences-in-differences method based on provincial panel data from 2005-2019, using a carbon emissions trading pilot as a quasi-natural experiment. The findings show that the policy can significantly promote green technology innovation, but with a lagged effect, and this finding still holds in the robustness test. Further heterogeneity analysis reveals that the stronger the human capital, the stronger the intellectual property protection and the stronger the marketization with better policy effects. In addition, carbon emissions trading policy can indirectly affect green technology innovation by influencing research investment.
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Carbono , Invenções , Humanos , Carbono/análise , Políticas , Investimentos em Saúde , ChinaRESUMO
Cancer has become one of the main causes of death worldwide. Chemotherapy as one of the main therapy modalities is very unsatisfactory. The various nanocarriers have brought new opportunities for effective tumor treatment. However, most of the current nanocarriers still suffer from low efficiency and confront significant challenges in overcoming multiple biological barriers. Compared with conventional nanocarriers, covalent organic frameworks (COFs) with unique and attractive features exhibited great potential to serve as a promising platform for anticancer drug delivery. In this review, we first summarize the strategies and challenges of nanocarriers for cancer chemotherapy and then highlight the recent advances in COF-based nanocarriers for improved delivery of chemotherapeutic agents. Finally, the challenges remaining for COF-based nanocarriers for clinical applications are outlined.
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Outburst floods related to glacial or landslide damming are a major agent of geomorphic change in mountain rivers. Although the evidence between outburst flooding and riverine landscapes has been gradually recognized, the lack of hydraulics to the extent that there has still not been quantified on the relationship of how the amount and spatial distribution of these changes relate quantitatively to the hydraulic conditions and durations of these catastrophic events. This study combined remote and field observations of the 2018 Baige outburst flood with two-dimensional numerical simulation using the diffusive wave equation. By feeding the measured dam-breach hydrograph and comparing three different Manning coefficients in numerical experiments, the simulation results show that when n = 0.055, the time of peak flow was only 0.5 h different from that indicated by measured data in Yebatan, 54 km downstream of the Baige landslide dam. Under high shear stress over several hours at sustained ~20 m water depth, lateral erosion caused by these outburst floods contributed to the adjacent landslide, which was activated in association with intermittent water velocity waves of approximately 17 m/s. Sustained high stream power (>50 kW m2) from the outburst flood eroded slope toes and accelerated slippage of six slopes. Combining simulation and observations, we also developed a physical model related to hillslope instability caused by high hydrodynamic erosion of riverbanks generated by flow waves lasting several hours, which explained the hydrodynamic response of the outburst flood to the canyon geomorphology. Furthermore, we suggest that the pattern of channel widening erosion and deposition is governed by the variation in shear stress and Froude number as the high-energy flood flows from a wide channel into a narrow river valley. Our findings highlight that the hydraulics of high-magnitude outburst floods and sediment transport play crucial roles in reshaping canyon geomorphology.
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Inundações , Rios , ÁguaRESUMO
A tunable multimode white emission Ca2(Mg0.5Al0.5)(Si1.5Al0.5O7):Eu2+/Eu3+ phosphor was prepared by doping Eu2O3 in molten high-aluminum blast furnace slag. The structural probe Eu2+ was studied during phase transformation between the glassy state and Ca2(Mg0.5Al0.5)(Si1.5Al0.5O7) crystals based on site-selective Eu2+ occupancy. When the doped Eu2+ ions occupied two different Ca2+ sites in the matrix, blue light (421 nm) and green light (516 nm) emissions were observed corresponding to two types of Eu2+Ca2+, namely Eu2+Ca2+ (Mg2+ â Al3+) and Eu2+Ca2+ (Si4+ â Al3+). The effects of Eu concentration (0.1-2.0 mol%), heat treatment temperature (800-1000 °C), and thermal quenching temperature (30-150 °C) on the structural evolution of the emission unit were studied by differential scanning calorimetry (DSC), photoluminescence spectroscopy (PL) and X-ray diffraction (XRD) analyses. The Eu2+Ca2+ (Mg2+ â Al3+) structure formed by site-selective Eu2+ occupancy possessed better structural stability in the Ca2(Mg0.5Al0.5)(Si1.5Al0.5O7) crystal matrix, in favour of light-emitting diode (LED) illumination and plasma display panels (PDPs).
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Severe acute respiratory syndrome coronavirus (SARS-CoV), SARS-CoV-2, and human coronavirus (hCoV)-NL63 utilize ACE2 as the functional receptor for cell entry, which leads to zoonotic infection. Horses (Equus caballus) attracted our attention because the spike protein receptor-binding domains (RBDs) of SARS-CoV-2 and SARS-CoV-2-related coronaviruses bind equine ACE2 (eACE2) with high affinity. Here we show that eACE2 binds the RBDs of these three coronaviruses and also SARS-CoV-2 variants but with lower affinities compared with human ACE2 (hACE2). Structural analysis and mutation assays indicated that eACE2-H41 accounts for the lower binding affinity of eACE2 to the RBDs of SARS-CoV-2 variants (Alpha, Beta, and Gamma), SARS-CoV, and hCoV-NL63. Pseudovirus infection assays showed that the SARS-CoV-2 Delta strain (B.1.617.2) displayed a significantly increased infection efficiency in eACE2-expressing HeLa cells. Our results reveal the molecular basis of eACE2 binding to the RBDs of SARS-CoV, SARS-CoV-2, and hCoV-NL63, which provides insights into the potential animal transmission of these ACE2-dependent coronaviruses.
