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Iron-chalcogenide superconductors FeSe1-xSx possess unique electronic properties such as nonmagnetic nematic order and its quantum critical point. The nature of superconductivity with such nematicity is important for understanding the mechanism of unconventional superconductivity. A recent theory suggested the possible emergence of a fundamentally new class of superconductivity with the so-called Bogoliubov Fermi surfaces (BFSs) in this system. However, such an ultranodal pair state requires broken time-reversal symmetry (TRS) in the superconducting state, which has not been observed experimentally. Here, we report muon spin relaxation (µSR) measurements in FeSe1-xSx superconductors for 0 ≤ x ≤ 0.22 covering both orthorhombic (nematic) and tetragonal phases. We find that the zero-field muon relaxation rate is enhanced below the superconducting transition temperature Tc for all compositions, indicating that the superconducting state breaks TRS both in the nematic and tetragonal phases. Moreover, the transverse-field µSR measurements reveal that the superfluid density shows an unexpected and substantial reduction in the tetragonal phase (x > 0.17). This implies that a significant fraction of electrons remain unpaired in the zero-temperature limit, which cannot be explained by the known unconventional superconducting states with point or line nodes. The TRS breaking and the suppressed superfluid density in the tetragonal phase, together with the reported enhanced zero-energy excitations, are consistent with the ultranodal pair state with BFSs. The present results reveal two different superconducting states with broken TRS separated by the nematic critical point in FeSe1-xSx, which calls for the theory of microscopic origins that account for the relation between nematicity and superconductivity.
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Phyllosilicates-based nanomaterials, particularly iron-rich vermiculite (VMT), have wide applications in biomedicine. However, the lack of effective methods to activate the functional layer covered by the external inert layer limits their future applications. Herein, we report a mineral phase reconfiguration strategy to prepare novel nanozymes by a molten salt method. The peroxidase-like activity of the VMT reconfiguration nanozyme is 10 times that of VMT, due to the electronic structure change of iron in VMT. Density-functional theory calculations confirmed that the upward shifted d-band center of the VMT reconfiguration nanozyme promoted the adsorption of H2O2 on the active iron sites and significantly elongated the O-O bond lengths. The reconfiguration nanozyme exhibited nearly 100% antibacterial activity toward Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), much higher than that of VMT (E. coli 10%, S. aureus 21%). This work provides new insights for the rational design of efficient bioactive phyllosilicates-based nanozyme.
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Escherichia coli , Staphylococcus aureus , Peróxido de Hidrogênio , Silicatos de Alumínio/farmacologia , Ferro , Antibacterianos/farmacologia , Antibacterianos/químicaRESUMO
Fatal dendritic growth in lithium metal batteries is closely related to the composition and thickness of the modified separator. Herein, an ultrathin nanocoating composed of monolayer montmorillonite (MMT), poly(vinyl alcohol) (PVA) on a polypropylene separator is prepared. The MMT was exfoliated into monolayers (only 0.96 nm) by intercalating PVA under ultrasound, followed by cross-linking with glutaraldehyde. The thickness of the nanocoating on the polypropylene separator, as determined using the pull-up method, is only 200-500 nm with excellent properties. As a result, the lithium-symmetric battery composed of it has a low overpotential (only 40 mV) and a long lifespan of more than 7900 h at high current density, because ion transport is unimpeded and Li+ flows uniformly through the ordered ion channels between the MMT layers. Additionally, the separator exhibited excellent cycling stability in Li-S batteries. This study offers a new idea for fabricating ultrathin clay/polymer modified separators for metal anode stable cycling at high current densities.
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The tooth serves as an exemplary model for developmental studies, encompassing epithelial-mesenchymal transition and cell differentiation. The essential factors and pathways identified in tooth development will help understand the natural development process and the malformations of mineralized tissues such as skeleton. The time-dependent proteomic changes were investigated through the proteomics of healthy human molars during embryonic stages, ranging from the cap-to-early bell stage. A comprehensive analysis revealed 713 differentially expressed proteins (DEPs) exhibiting five distinct temporal expression patterns. Through the application of weighted gene co-expression network analysis (WGCNA), 24 potential driver proteins of tooth development were screened, including CHID1, RAP1GDS1, HAPLN3, AKAP12, WLS, GSS, DDAH1, CLSTN1, AFM, RBP1, AGO1, SET, HMGB2, HMGB1, ANP32A, SPON1, FREM1, C8B, PRPS2, FCHO2, PPP1R12A, GPALPP1, U2AF2, and RCC2. Then, the proteomics and transcriptomics expression patterns of these proteins were further compared, complemented by single-cell RNA-sequencing (scRNA-seq). In summary, this study not only offers a wealth of information regarding the molecular intricacies of human embryonic epithelial and mesenchymal cell differentiation but also serves as an invaluable resource for future mechanistic inquiries into tooth development.
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Recent years have witnessed great research interests in developing high-performance electrocatalysts for the two-electron (2e-) oxygen reduction reaction (ORR) that enables the sustainable and flexible synthesis of H2O2. Carbon-based electrocatalysts exhibit attractive catalytic performance for the 2e- ORR, where oxygen-containing functional groups (OFGs) play a decisive role. However, current understanding is far from adequate, and the contribution of OFGs to the catalytic performance remains controversial. Therefore, a critical overview on OFGs in carbon-based electrocatalysts toward the 2e- ORR is highly desirable. Herein, we go over the methods for constructing OFGs in carbon including chemical oxidation, electrochemical oxidation, and precursor inheritance. Then we review the roles of OFGs in activating carbon toward the 2e- ORR, focusing on the intrinsic activity of different OFGs and the interplay between OFGs and metal species or defects. At last, we discuss the reasons for inconsistencies among different studies, and personal perspectives on the future development in this field are provided. The results provide insights into the origin of high catalytic activity and selectivity of carbon-based electrocatalysts toward the 2e- ORR and would provide theoretical foundations for the future development in this field.
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The development of efficient methods for the direct introduction of a methyl group into molecules is becoming increasingly important. Herein, the ß-methylation of primary alcohols with methanol has been accomplished under environmentally benign conditions using [Cp*Ir(2,2'-bpyO)(H2O)] as a catalyst. It was found that functional groups in the ligand are crucially important for the activity of the iridium complex. Furthermore, the mechanistic research and application potential of our catalytic system are also presented.
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BACKGROUND: Prader-Willi syndrome (PWS) is a rare genetic disease often associated with bone problems, mainly scoliosis and hip dysplasia (HD). This study aimed to analyze the clinical characteristics of orthopedic deformities in patients with PWS. METHODS: A retrospective study was conducted on 175 patients up to March 2023. The Cobb angle(CA) of the spine, the alpha angle of the hip joint, and the acetabular index (AI) were measured. This study aimed to evaluate the relationship between demographic parameters and bone deformities. RESULTS: Scoliosis was found in 66 patients (43.7%), including 52 (78.8%) with mild scoliosis, 10 (15.2%) with moderate scoliosis, and 4 (6.1%) with severe scoliosis. Only seven patients received orthopedic treatment (10.6%). The median age of scoliosis was 4.5 years old, and the prevalence of scoliosis increased rapidly at the age of 5 years and adolescence. The mean CA in this study increased gradually with age. HD was found in 47 patients (38.2%), and 6 patients received orthopedic treatment (12.7%). The median age at HD was 1.8 years old. The mean AI of the study population decreased with age. The prevalence of HD treated with recombinant human growth hormone (rhGH) was low. No significant differences were observed in sex, genotype, body mass index (BMI), obesity rate, or onset of scoliosis and HD. CONCLUSION: The prevalence of scoliosis and HD was higher in patients with PWS. The onset age and developmental trends of the different skeletal malformations were different. Early diagnosis and treatment are important for the prognosis and treatment of orthopedic diseases in patients with PWS.
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Hormônio do Crescimento Humano , Síndrome de Prader-Willi , Escoliose , Criança , Adolescente , Humanos , Pré-Escolar , Lactente , Síndrome de Prader-Willi/complicações , Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/tratamento farmacológico , Escoliose/etiologia , Estudos Retrospectivos , Hormônio do Crescimento Humano/uso terapêutico , Obesidade/complicaçõesRESUMO
Strong metal-support interaction (SMSI) is crucial to modulating the nature of metal species, yet the SMSI behaviors of sub-nanometer metal clusters remain unknown due to the difficulties in constructing SMSI at cluster scale. Herein, we achieve the successful construction of the SMSI between Pt clusters and amorphous TiO2 nanosheets by vacuum annealing, which requires a relatively low temperature that avoids the aggregation of small clusters. In situ scanning transmission electron microscopy observation is employed to explore the SMSI behaviors, and the results reveal the dynamic rearrangement of Pt atoms upon annealing for the first time. The originally disordered Pt atoms become ordered as the crystallizing of the amorphous TiO2 support, forming an epitaxial interface between Pt and TiO2. Such a SMSI state can remain stable in oxidation environment even at 400 °C. Further investigations prove that the electron transfer from TiO2 to Pt occupies the Pt 5d orbitals, which is responsible for the disappeared CO adsorption ability of Pt/TiO2 after forming SMSI. This work not only opens a new avenue for constructing SMSI at cluster scale but also provides in-depth understanding on the unique SMSI behavior, which would stimulate the development of supported metal clusters for catalysis applications.
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This study aimed to investigate whether Enfortumab vedotin (EV) is suitable for patients with locally advanced or metastatic urothelial carcinoma and to perform a meta-analysis of its efficacy and safety. Five studies involved 584 patients were included in the meta-analysis. The results of single-arm meta-analysis showed that with EV at 1.25 mg/kg, the objective response rate (ORR) was 47%. The meta-analysis indicated that EV showed good efficacy and safety in the patient population of locally advanced or metastatic urothelial carcinoma.
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Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Neoplasias Urológicas , Humanos , Carcinoma de Células de Transição/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias Urológicas/tratamento farmacológico , Neoplasias Urológicas/patologia , Anticorpos Monoclonais/efeitos adversosRESUMO
Photochemically generated reactive oxygen species (ROS) play numerous key roles in earth's surface biogeochemical processes and pollutant dynamics. ROS production has historically been linked to the photosensitization of natural organic matter. Here, we report the photochemical ROS production from three naturally abundant iron minerals. All investigated iron minerals are photoactive toward sunlight irradiation, with photogenerated currents linearly correlated with incident light intensity. Hydroxyl radicals (â¢OH) and hydrogen peroxide (H2O2) are identified as the major ROS species, with apparent quantum yields ranging from 1.4 × 10-8 to 3.9 × 10-8 and 5.8 × 10-8 to 2.5 × 10-6, respectively. Photochemical ROS production exhibits high wavelength dependence, for instance, the â¢OH quantum yield decreases with the increase of light wavelength from 375 to 425 nm, and above 425 nm it sharply decreases to zero. The temperature shows a positive impact on â¢OH production, with apparent activation energies ranging from 8.0 to 17.8 kJ/mol. Interestingly, natural iron minerals with impurities exhibit higher ROS production than their pure crystal counterparts. Compared with organic photosensitizers, iron minerals exhibit higher wavelength dependence, higher selectivity, lower efficiency, and long-term stability in photochemical ROS production. Our study highlights natural inorganic iron mineral photochemistry as a ubiquitous yet previously overlooked source of ROS.
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Ferro , Luz Solar , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio/química , MineraisRESUMO
Reactive oxygen species (ROS) play key roles in driving biogeochemical processes. Recent studies have revealed nonphotochemical electron transfer from redox-active substances (e.g., iron minerals) to oxygen as a new route for ROS production. Yet, naturally occurring iron minerals mainly exist in thermodynamically stable forms, restraining their potential for driving ROS production. Here, we report that tide-induced redox oscillations can activate thermodynamically stable iron minerals for enhanced ROS production. â¢OH production in intertidal soils (15.8 ± 0.5 µmol/m2) was found to be 5.9-fold more efficient than those in supratidal soils. Moreover, incubation of supratidal soils under tidal redox fluctuations dramatically enhanced â¢OH production by 4.3-fold. The tidal hydrology triggered redox alternation between biotic reduction and abiotic oxidation and could accelerate the production of reactive ferrous ions and amorphous ferric oxyhydroxides, making thermodynamically stable iron minerals into redox-active metastable iron phases (RAMPs) with reduced crystallinity and promoting surface electrochemical activities. Those RAMPs displayed enhanced redox activity for ROS production. Investigations of nationwide coastal soils verified that tide-induced redox oscillations could ubiquitously activate soils for enhanced ROS production. Our study demonstrates the effective formation of RAMPs from redox oscillations by hydrological perturbations, which provides new insights into natural ROS sources.
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Ferro , Minerais , Ferro/química , Espécies Reativas de Oxigênio , Minerais/química , Compostos Férricos , Oxirredução , SoloRESUMO
The hydroxyl radical (â¢OH) is a potent oxidant and key reactive species in mediating element cycles and pollutant dynamics in the natural environment. The natural source of â¢OH is historically linked to photochemical processes (e.g., photoactivation of natural organic matter or iron minerals) or redox chemical processes (e.g., reaction of microbe-excreted or reduced iron/natural organic matter/sulfide-released electrons with O2 in soils and sediments). This study revealed a ubiquitous source of â¢OH production via water vapor condensation on iron mineral surfaces. Distinct â¢OH productions (15-478 nM via water vapor condensation) were observed on all investigated iron minerals of abundant natural occurrence (i.e., goethite, hematite, and magnetite). The spontaneous â¢OH productions were triggered by contact electrification and Fenton-like activation of hydrogen peroxide (H2O2) at the water-iron mineral interface. Those â¢OH drove efficient transformation of organic pollutants associated on iron mineral surfaces. After 240 cycles of water vapor condensation and evaporation, bisphenol A and carbamazepine degraded by 25%-100% and 16%-51%, respectively, forming â¢OH-mediated arene/alkene hydroxylation products. Our findings largely broaden the natural source of â¢OH. Given the ubiquitous existence of iron minerals on Earth's surface, those newly discovered â¢OH could play a role in the transformation of pollutants and organic carbon associated with iron mineral surfaces.
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Poluentes Ambientais , Ferro , Radical Hidroxila , Vapor , Peróxido de Hidrogênio , Minerais , OxirreduçãoRESUMO
Diphenyl ether herbicides, typical globally used herbicides, threaten the agricultural environment and the sensitive crops. The microbial degradation pathways of diphenyl ether herbicides are well studied, but the nitroreduction of diphenyl ether herbicides by purified enzymes is still unclear. Here, the gene dnrA, encoding a nitroreductase DnrA responsible for the reduction of nitro to amino groups, was identified from the strain Bacillus sp. Za. DnrA had a broad substrate spectrum, and the Km values of DnrA for different diphenyl ether herbicides were 20.67 µM (fomesafen), 23.64 µM (bifenox), 26.19 µM (fluoroglycofen), 28.24 µM (acifluorfen), and 36.32 µM (lactofen). DnrA also mitigated the growth inhibition effect on cucumber and sorghum through nitroreduction. Molecular docking revealed the mechanisms of the compounds fomesafen, bifenox, fluoroglycofen, lactofen, and acifluorfen with DnrA. Fomesafen showed higher affinities and lower binding energy values for DnrA, and residue Arg244 affected the affinity between diphenyl ether herbicides and DnrA. This research provides new genetic resources and insights into the microbial remediation of diphenyl ether herbicide-contaminated environments. KEY POINTS: ⢠Nitroreductase DnrA transforms the nitro group of diphenyl ether herbicides. ⢠Nitroreductase DnrA reduces the toxicity of diphenyl ether herbicides. ⢠The distance between Arg244 and the herbicides is related to catalytic efficiency.
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Bacillus , Herbicidas , Bacillus/genética , Bacillus/metabolismo , Herbicidas/metabolismo , Simulação de Acoplamento Molecular , Éteres Difenil Halogenados , Biotransformação , Nitrorredutases/química , Nitrorredutases/genética , Nitrorredutases/metabolismoRESUMO
Developing efficient platinum (Pt)-based electrocatalysts with high tolerance to CO poisoning for the methanol oxidation reaction is critical for the development of direct methanol fuel cells. In this work, cobalt single atoms are introduced to enhance the electrocatalytic performance of N-doped carbon supported Pt (N-C/Pt) for the methanol oxidation reaction. The cobalt single atoms are believed to play a critical role in accelerating the prompt oxidation of CO to CO2 and minimizing the CO blocking of the adjacent Pt active sites. Benefitting from the synergistic effects among the Co single atoms, the Pt nanoparticles, and the N-doped carbon support, the Co-modified N-C/Pt (Co-N-C/Pt) electrocatalyst simultaneously delivers impressive electrocatalytic activity and durability with lower onset potential and superb CO poisoning resistance as compared to the N-C/Pt and the commercial Pt/C electrocatalysts.
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We report an unrecognized, tidal source of reactive oxygen species (ROS). Using a newly developed ROS-trapping gel film, we observed hot spots for ROS generation within â¼2.5 mm of coastal surface soil. Kinetic analyses showed rapid production of hydroxyl radicals (â¢OH), superoxide (O2â¢-), and hydrogen peroxide (H2O2) upon a shift from high tide to low tide. The ROS production exhibited a distinct rhythmic fluctuation. The oscillations of the redox potential and dissolved oxygen concentration followed the same pattern as the â¢OH production, suggesting the alternating oxic-anoxic conditions as the main geochemical drive for ROS production. Nationwide coastal field investigations confirmed the widespread and sustainable production of ROS via tidal processes (22.1-117.4 µmol/m2/day), which was 5- to 36-fold more efficient than those via classical photochemical routes (1.5-7.6 µmol/m2/day). Analyses of soil physicochemical properties demonstrated that soil redox-metastable components such as redox-active iron minerals and organic matter played a key role in storing electrons at high tide and shuttling electrons to infiltrated oxygen at low tide for ROS production. Our work sheds light on a ubiquitous but previously overlooked tidal source of ROS, which may accelerate carbon and metal cycles as well as pollutant degradation in coastal soils.
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Peróxido de Hidrogênio , Solo , Radical Hidroxila , Oxirredução , Oxigênio , Espécies Reativas de Oxigênio/metabolismoRESUMO
STUDY OBJECTIVES: The aim of the study was to evaluate the clinical efficacy of nasal surgery in the treatment of obstructive sleep apnoea (OSA) by comparing the improvement of subjective symptoms and objective metrics before surgery and after 6 months of surgery. METHODS: Patients with the main complaint of nasal congestion combined with habitual snoring who were hospitalized and treated were selected. Patients underwent subjective symptom tests and objective indicator monitoring both before surgery and 6 months after surgery. Comparisons between groups were performed using the independent samples t-test. RESULTS: Subjective scale evaluations demonstrated that nasal congestion, daytime sleepiness, snoring, nose-related symptoms, and sleep symptoms in patients with simple snoring or with OSA were improved after nasal surgery. Additionally, vitality was improved in all groups except for the patients with simple snoring and emotional consequence was improved in patients with simple snoring and mild OSA. Objective evaluations indicated the apnoea-hypopnoea index (AHI), the thickness of the soft palate, and the maximum cross-sectional area of the sagittal plane of the soft palate decreased after surgery in patients with mild OSA. The lowest blood oxygen concentration (LSaO2) and anteroposterior diameter of the soft palate increased after surgery in patients with mild OSA. The arousal index also significantly decreased in patients with mild and moderate OSA. The nasal cavity volumes (NCVs) and the nasal minimal cross-sectional areas (NMCAs) of all groups showed significant differences after surgery. CONCLUSIONS: Nasal surgery can effectively improve nose and sleep symptoms in patients with simple snoring or with OSA. It can significantly reduce the nasal resistance and increase the ventilation volume. STATEMENT OF SIGNIFICANCE: Obstructive sleep apnoea (OSA) is becoming a global health problem. OSA is associated with several coexisting conditions, reduced health-related quality of life, and impaired work productivity. This study performed nasal surgery on OSA patients with the main complaint of nasal congestion combined with snoring and patients with simple snoring to compare the improvement of subjective symptoms and objective metrics before and after surgery. We found that: (1) symptoms such as nasal congestion, daytime sleepiness or snoring were improved after nasal surgery; (2) the apnoea-hypopnoea index (AHI) and arousal index decreased after surgery in patients with OSA; (3) the nasal and oropharyngeal cavity volumes increased after surgery. These findings suggest that patients with OSA or with simple snoring could benefit from nasal surgery.
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Procedimentos Cirúrgicos Nasais/métodos , Apneia Obstrutiva do Sono/cirurgia , Adulto , Nível de Alerta , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/patologia , Orofaringe/patologia , Palato Mole/patologia , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/patologia , Apneia Obstrutiva do Sono/fisiopatologia , Ronco/etiologia , Ronco/cirurgia , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Precise manipulation of the interactions between different components represents the frontier of heterostructured electrocatalysts and is crucial to understanding the structure-function relationship. Current studies, however, are quite limited. Here, we report targeted modulation of the atomic-level interface chemistry of Pt/NiO heterostructure via an annealing treatment, which results in substantially enhanced hydrogen electrocatalysis kinetics in alkaline media. Specifically, the optimized Pt/NiO heterostructure delivers by far the highest specific exchange current density of 8.1 mA cmPt-2 for hydrogen oxidation reaction. X-ray spectroscopy results suggest Pt-Ni interfacial bonds are formed after annealing, inducing more significant electron transfer from NiO to Pt. Also, the regulated interface chemistry, as proven by theoretical calculations, optimizes the binding behaviors of hydrogen and hydroxyl species. These findings emphasize the importance of interface engineering at the atomic level and inspire further explorations of heterostructured electrocatalysts.
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The rotational Doppler effect caused by vortex beam carrying orbital angular momentum is recently used to estimate the rotational velocity of the object. However, the vortex beam only has the spiral phase distribution in one dimension, which means that only the rotational movement of the object would introduce the frequency shift. Also, the vortex beam has a spatial amplitude distribution of doughnut-shaped, which is not suitable for many application scenarios. To simultaneously measure the velocity of an arbitrary three-dimensional moving object, we propose theoretically and demonstrate experimentally an effective method by constructing a novel modulated field. Different from the plane wave and the vortex beam, the modulated field has linear phase distribution in azimuth and elevation directions. In addition, the modulated field has the maximal radiation intensity in the center, which avoids the beam divergence of the vortex beam. By decomposing the frequency shift caused by the radial, azimuth and elevation movements, we realize the velocity measurement in three dimensions. Experiments in a microwave system show that the estimated velocity errors are lower than 6.0%.
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Photochemically produced reactive intermediates (PPRIs) by natural photosensitizers such as chromophoric dissolved organic matter (CDOM) play numerous key roles in aquatic biogeochemical processes. PPRI productions rely on both the intensity and the spectrum of incident sunlight. While the impacts of sunlight intensity on PPRI productions are well-studied, there remains insufficient understanding of the spectrum-dependence of PPRI productions. Here we designed a high sample throughput reactor equipped with monochromatic LED lights for systematic assessments of wavelength-dependent productions of four important PPRI species, i.e., triplet-state excited CDOM (3CDOM*), singlet oxygen (1O2), hydrogen peroxide (H2O2), and hydroxyl radical (â¢OH), in CDOM solutions. The quantum yields of PPRIs followed the order: 3CDOM* > 1O2 â« H2O2 > â¢OH. Moreover, PPRI quantum yields decreased with the light wavelength increasing from 375 to 490 nm and sharply decreased to zero above 490 nm, while the shapes of quantum yield spectra differed among PPRI species. Simulations on PPRI productions under varying season, latitude, altitude, and cloud cover conditions show that the sunlight spectrum plays a role as equally important as intensity in determining PPRI productions and PPRI-mediated transformations of aquatic nutrients and micropollutants. Therefore, incorporating the spectrum dependence of PPRI productions will advance our understandings of PPRI-driven biogeochemical processes and pollutant dynamics under varying spatial-temporal and climatic conditions. Regarding this, the high sample throughput LED reactor sheds light on a new approach for the facile characterization of PPRI quantum yield spectrum.
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Matéria Orgânica Dissolvida , Peróxido de Hidrogênio , Radical Hidroxila , Oxigênio Singlete , Luz SolarRESUMO
PURPOSE: To develop and evaluate a model for obstructive sleep apnea (OSA) detection using an artificial neural network (ANN) based on the combined features of body mass index (BMI), electrocardiogram (ECG), and pulse oxygen saturation (SpO2). METHODS: Polysomnography (PSG) data for 148 patients with OSA and 33 unaffected individuals were included. A multi-layer feed-forward neural network (FNN) was used based on the features obtained from ECG, SpO2, and BMI. The receiver operating characteristic (ROC) curve and the metrics of accuracy, sensitivity, and specificity were used to evaluate the performance of the overall classification. Some other machine learning methods including linear discriminant, linear Support Vector Machine (SVM), Complex Tree, RUSBoosted Trees, and Logistic Regression were also used to compare their performance with the FNN. RESULTS: The accuracy, sensitivity, and specificity of the proposed multi-layer FNN were 97.8%, 98.6%, and 93.9%, respectively, and the area under the ROC curve was 97.0%. Compared with the other machine learning methods mentioned above, the FNN achieved the highest performance. CONCLUSIONS: The satisfactory performance of the proposed FNN model for OSA detection indicated that it is reliable to screen potential patients with OSA using the combined channels of ECG and SpO2 and also taking into account BMI. This strategy might be a viable alternative method for OSA diagnosis.