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1.
Vaccine ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38796326

RESUMO

We conducted a phase I, randomized, double-blind, placebo-controlled trial including healthy adults in Sui County, Henan Province, China. Ninety-six adults were randomly assigned to one of three groups (high-dose, medium-dose, and low-dose) at a 3:1 ratio to receive one vaccine dose or placebo. Adverse events up to 28 days after each dose and serious adverse events up to 6 months after all doses were reported. Geometric mean titers and seroconversion rates were measured for anti-rotavirus neutralizing antibodies using microneutralization tests. The rates of total adverse events in the placebo group, low-dose group, medium-dose group, and high-dose group were 29.17 % (12.62 %-51.09 %), 12.50 % (2.66 %-32.36 %), 50.00 % (29.12 %-70.88 %), and 41.67 % (22.11 %-63.36 %), respectively, with no significant difference in the experimental groups compared with the placebo group. The results of the neutralizing antibody assay showed that in the adult group, the neutralizing antibody geometric mean titer at 28 days after full immunization in the low-dose group was 583.01 (95 % confidence interval [CI]: 447.12-760.20), that in the medium-dose group was 899.34 (95 % CI: 601.73-1344.14), and that in the high-dose group was 1055.24 (95 % CI: 876.28-1270.75). The GMT of serum-specific IgG at 28 days after full immunization in the low-dose group was 3444.26 (95 % CI: 2292.35-5175.02), that in the medium-dose group was 6888.55 (95 % CI: 4426.67-10719.6), and that in the high-dose group was 7511.99 (95 % CI: 3988.27-14149.0). The GMT of serum-specific IgA at 28 days after full immunization in the low-dose group was 2332.14 (95 % CI: 1538.82-3534.45), that in the medium-dose group was 4800.98 (95 % CI: 2986.64-7717.50), and that in the high-dose group was 3204.30 (95 % CI: 2175.66-4719.27). In terms of safety, adverse events were mainly Grades 1 and 2, indicating that the safety of the vaccine is within the acceptable range in the healthy adult population. Considering the GMT and positive transfer rate of neutralizing antibodies for the main immunogenicity endpoints in the experimental groups, it was initially observed that the high-dose group had higher levels of neutralizing antibodies than the medium- and low-dose groups in adults aged 18-49 years. This novel inactivated rotavirus vaccine was generally well-tolerated in adults, and the vaccine was immunogenic in adults (ClinicalTrials.gov number, NCT04626856).

2.
World J Psychiatry ; 14(4): 553-562, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38659604

RESUMO

BACKGROUND: This study employs a descriptive phenomenological approach to investigate the challenges anesthesia nurses face in managing emergence delirium (ED), a common and complex postoperative complication in the post-anesthesia care unit. The role of nurses in managing ED is critical, yet research on their understanding and management strategies for ED is lacking. AIM: To investigate anesthetic nurses' cognition and management experiences of ED in hopes of developing a standardized management protocol. METHODS: This study employed a descriptive phenomenological approach from qualitative research methodologies. Purposeful sampling was utilized to select 12 anesthetic nurses from a tertiary hospital in Shanghai as research subjects. Semi-structured interviews were conducted, and the data were organized and analyzed using Colaizzi's seven-step analysis method, from which the final themes were extracted. RESULTS: After analyzing the interview content, four main themes and eight subthemes were distilled: Inefficient cognition hinders the identification of ED (conceptual ambiguity, empirical identification), managing diversity and challenges (patient-centered safe care, low level of medical-nursing collaboration), work responsibilities and pressure coexist (heavy work responsibilities, occupational risks and stress), demand for high-quality management (expecting the construction of predictive assessment tools and prevention strategies, and pursuing standardized management processes to enhance management effectiveness). CONCLUSION: Nursing managers should prioritize the needs and suggestions of nurses in order to enhance their nursing capabilities and provide guidance for standardized management processes.

3.
J Refract Surg ; 40(3): e164-e172, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38466765

RESUMO

PURPOSE: To evaluate the dynamic changes in anterior segment parameters during accommodation following Implantable Collamer Lens (ICL) implantation with swept-source optical coherence tomography (SS-OCT). METHODS: Under the accommodation of 0.00 diopters (D), 3.00 D, and maximum amplitude, SS-OCT was used to examine the anterior segment parameters, including ICL vault, ICL depth (the distance between the corneal endothelium and the posterior surface of ICL), crystalline lens thickness, anterior chamber depth, and various parameters of the anterior chamber angle, comprising angle opening distance, angle recess area, trabecular iris space area, and trabecular iris angle. RESULTS: During accommodation, the ICL vault showed a significant decrease from baseline (536 ± 278 µm) to 3.00 D (522 ± 281 µm), followed by an increase from 3.00 D to maximum amplitude (548 ± 306 µm) (analysis of variance [ANOVA], P < .001). Four eyes (2.61%) exhibited a decrease in ICL vault to less than 100 µm (47 ± 32 µm) at maximum accommodation. The ICL depth decreased significantly as accommodation increased (ANOVA, P < .001). Crystalline lens thickness increased, whereas anterior chamber depth decreased during accommodation (ANOVA, P < .001). The anterior chamber angle widened during 3.00 D of accommodation but narrowed at maximum accommodation, leading to significant changes in the angle opening distance, angle recess area, trabecular iris space area, and trabecular iris angle during accommodation (ANOVA, P < .001 for all). CONCLUSIONS: The anterior segment, including ICL vault and anterior chamber angle, undergo significant dynamic changes during accommodation. These accommodative changes may require careful monitoring for the surgery design of ICL implantation. [J Refract Surg. 2024;40(3):e164-e172.].


Assuntos
Cristalino , Miopia , Lentes Intraoculares Fácicas , Humanos , Implante de Lente Intraocular/métodos , Miopia/cirurgia , Acomodação Ocular , Câmara Anterior/diagnóstico por imagem , Pseudofacia/cirurgia , Tomografia de Coerência Óptica , Biometria
4.
Nat Commun ; 14(1): 7155, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935701

RESUMO

The infinite-layer nickelates, isostructural to the high-Tc cuprate superconductors, have emerged as a promising platform to host unconventional superconductivity and stimulated growing interest in the condensed matter community. Despite considerable attention, the superconducting pairing symmetry of the nickelate superconductors, the fundamental characteristic of a superconducting state, is still under debate. Moreover, the strong electronic correlation in the nickelates may give rise to a rich phase diagram, where the underlying interplay between the superconductivity and other emerging quantum states with broken symmetry is awaiting exploration. Here, we study the angular dependence of the transport properties of the infinite-layer nickelate Nd0.8Sr0.2NiO2 superconducting films with Corbino-disk configuration. The azimuthal angular dependence of the magnetoresistance (R(φ)) manifests the rotational symmetry breaking from isotropy to four-fold (C4) anisotropy with increasing magnetic field, revealing a symmetry-breaking phase transition. Approaching the low-temperature and large-magnetic-field regime, an additional two-fold (C2) symmetric component in the R(φ) curves and an anomalous upturn of the temperature-dependent critical field are observed simultaneously, suggesting the emergence of an exotic electronic phase. Our work uncovers the evolution of the quantum states with different rotational symmetries in nickelate superconductors and provides deep insight into their global phase diagram.

5.
Natl Sci Rev ; 10(11): nwad112, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37818115

RESUMO

The recent discovery of superconductivity in infinite-layer nickelates generates tremendous research endeavors, but the ground state of their parent compounds is still under debate. Here, we report experimental evidence for the dominant role of Kondo scattering in the underdoped Nd1-xSrxNiO2 thin films. A resistivity minimum associated with logarithmic temperature dependence in both longitudinal and Hall resistivities are observed in the underdoped Nd1-xSrxNiO2 samples before the superconducting transition. At lower temperatures down to 0.04 K, the resistivities become saturated, following the prediction of the Kondo model. A linear scaling behavior [Formula: see text] between anomalous Hall conductivity [Formula: see text] and conductivity [Formula: see text]is revealed, verifying the dominant Kondo scattering at low temperature. The effect of weak (anti-)localization is found to be secondary. Our experiments can help in clarifying the basic physics in the underdoped Nd1-xSrxNiO2 infinite-layer thin films.

6.
Nat Commun ; 14(1): 5477, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37673936

RESUMO

A charge order (CO) with a wavevector [Formula: see text] is observed in infinite-layer nickelates. Here we use first-principles calculations to demonstrate a charge-transfer-driven CO mechanism in infinite-layer nickelates, which leads to a characteristic Ni1+-Ni2+-Ni1+ stripe state. For every three Ni atoms, due to the presence of near-Fermi-level conduction bands, Hubbard interaction on Ni-d orbitals transfers electrons on one Ni atom to conduction bands and leaves electrons on the other two Ni atoms to become more localized. We further derive a low-energy effective model to elucidate that the CO state arises from a delicate competition between Hubbard interaction on Ni-d orbitals and charge transfer energy between Ni-d orbitals and conduction bands. With physically reasonable parameters, [Formula: see text] CO state is more stable than uniform paramagnetic state and usual checkerboard antiferromagnetic state. Our work highlights the multi-band nature of infinite-layer nickelates, which leads to some distinctive correlated properties that are not found in cuprates.

7.
Chemosphere ; 341: 139995, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37652241

RESUMO

As two emerging pollutants of great concern, microplastics (MPs) and antibiotics inevitably cooccur in various aquatic environments and interact with each other, impacting the fate and ecological risks. Aging obviously complicates their interaction and deserves further study. Therefore, the adsorption-desorption behaviors of ciprofloxacin (CIP) onto polystyrene (PS) fragments with various aging extent were investigated, and the key physiochemical properties influencing the interaction and the interaction mechanisms were clarified by redundancy analysis, FTIR and XPS spectra. The physicochemical properties of PS MPs were significantly changed with aging time, and the morphological and chemical changes seemed to occur asynchronously. The adsorption of CIP onto the pristine PS MPs relied on physisorption, especially the ion-involving electrostatic and cation-π interaction. Due to the hydrogen bonding formed by the C-OH, CO, and O-CO groups of PS and CIP, the adsorption capacities of the aged PS MPs were greatly increased. The desorption efficiency of CIP from MPs in the gastric fluid was closely related to the solution ionic strengths, C-OH and CO groups of MPs, while that in the intestinal fluid was associated with O-CO groups of MPs. The different impact factors could be well described by the differences in the chemical components and pHs of the simulated gastric and intestinal fluids. This study gives a comprehensive understanding of the adsorption-desorption behaviors of antibiotics onto MPs at a molecular level and indicates that MPs could act as Trojan horses to transport antibiotics into aquatic organisms.


Assuntos
Poliestirenos , Poluentes Químicos da Água , Poliestirenos/análise , Plásticos/química , Ciprofloxacina/análise , Adsorção , Poluentes Químicos da Água/análise , Microplásticos/química , Antibacterianos
8.
Eur J Neurosci ; 58(4): 2961-2984, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37518943

RESUMO

Post-stroke depression, a common complication after stroke, severely affects the recovery and quality of life of patients with stroke. Owing to its complex mechanisms, post-stroke depression treatment remains highly challenging. Hippocampal synaptic plasticity is one of the key factors leading to post-stroke depression; however, the precise molecular mechanisms remain unclear. Numerous studies have found that neurotrophic factors, protein kinases and neurotransmitters influence depressive behaviour by modulating hippocampal synaptic plasticity. This review further elaborates on the role of hippocampal synaptic plasticity in post-stroke depression by summarizing recent research and analysing possible molecular mechanisms. Evidence for the correlation between hippocampal mechanisms and post-stroke depression helps to better understand the pathological process of post-stroke depression and improve its treatment.


Assuntos
Depressão , Qualidade de Vida , Humanos , Depressão/etiologia , Plasticidade Neuronal/fisiologia , Hipocampo/metabolismo , Fatores de Crescimento Neural/metabolismo
9.
Open Med (Wars) ; 18(1): 20230755, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426050

RESUMO

[This corrects the article DOI: 10.1515/med-2021-0319.].

10.
Nature ; 621(7979): 493-498, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37437603

RESUMO

Although high-transition-temperature (high-Tc) superconductivity in cuprates has been known for more than three decades, the underlying mechanism remains unknown1-4. Cuprates are the only unconventional superconductors that exhibit bulk superconductivity with Tc above the liquid-nitrogen boiling temperature of 77 K. Here we observe that high-pressure resistance and mutual inductive magnetic susceptibility measurements showed signatures of superconductivity in single crystals of La3Ni2O7 with maximum Tc of 80 K at pressures between 14.0 GPa and 43.5 GPa. The superconducting phase under high pressure has an orthorhombic structure of Fmmm space group with the [Formula: see text] and [Formula: see text] orbitals of Ni cations strongly mixing with oxygen 2p orbitals. Our density functional theory calculations indicate that the superconductivity emerges coincidently with the metallization of the σ-bonding bands under the Fermi level, consisting of the [Formula: see text] orbitals with the apical oxygen ions connecting the Ni-O bilayers. Thus, our discoveries provide not only important clues for the high-Tc superconductivity in this Ruddlesden-Popper double-layered perovskite nickelates but also a previously unknown family of compounds to investigate the high-Tc superconductivity mechanism.

11.
Front Psychiatry ; 13: 1043846, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386995

RESUMO

Despite extensive research in recent decades, knowledge of the pathophysiology of depression in neural circuits remains limited. Recently, the lateral habenula (LHb) has been extensively reported to undergo a series of adaptive changes at multiple levels during the depression state. As a crucial relay in brain networks associated with emotion regulation, LHb receives excitatory or inhibitory projections from upstream brain regions related to stress and cognition and interacts with brain regions involved in emotion regulation. A series of pathological alterations induced by aberrant inputs cause abnormal function of the LHb, resulting in dysregulation of mood and motivation, which present with depressive-like phenotypes in rodents. Herein, we systematically combed advances from rodents, summarized changes in the LHb and related neural circuits in depression, and attempted to analyze the intrinsic logical relationship among these pathological alterations. We expect that this summary will greatly enhance our understanding of the pathological processes of depression. This is advantageous for fostering the understanding and screening of potential antidepressant targets against LHb.

12.
Front Mol Neurosci ; 15: 979483, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277498

RESUMO

Objective: Trigeminal neuralgia (TN), one of the most severe and debilitating chronic pain conditions, is often accompanied by mood disorders, such as anxiety and depression. Electroacupuncture (EA) is a characteristic therapy of Traditional Chinese Medicine with analgesic and anxiolytic effects. This study aimed to investigate whether EA ameliorates abnormal TN orofacial pain and anxiety-like behavior by altering synaptic plasticity in the hippocampus CA1. Materials and methods: A mouse infraorbital nerve transection model (pT-ION) of neuropathic pain was established, and EA or sham EA was used to treat ipsilateral acupuncture points (GV20-Baihui and ST7-Xiaguan). Golgi-Cox staining and transmission electron microscopy (TEM) were administrated to observe the changes of synaptic plasticity in the hippocampus CA1. Results: Stable and persistent orofacial allodynia and anxiety-like behaviors induced by pT-ION were related to changes in hippocampal synaptic plasticity. Golgi stainings showed a decrease in the density of dendritic spines, especially mushroom-type dendritic spines, in hippocampal CA1 neurons of pT-ION mice. TEM results showed that the density of synapses, membrane thickness of the postsynaptic density, and length of the synaptic active zone were decreased, whereas the width of the synaptic cleft was increased in pT-ION mice. EA attenuated pT-ION-induced orofacial allodynia and anxiety-like behaviors and effectively reversed the abnormal changes in dendritic spines and synapse of the hippocampal CA1 region. Conclusion: EA modulates synaptic plasticity of hippocampal CA1 neurons, thereby reducing abnormal orofacial pain and anxiety-like behavior. This provides evidence for a TN treatment strategy.

13.
Phys Rev Lett ; 128(19): 195301, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35622050

RESUMO

It is known that the loss of phase coherence of Cooper pairs in two-dimensional superconductivity corresponds to the unbinding of vortex-antivortex pairs with the quasi-long-range order in the order-parameter phase field, described by the Berezinskii-Kosterlizt-Thouless (BKT) transition of a 2D XY model. Here we show that the second-order Josephson coupling can induce an exotic superconducting phase in a bilayer system. By using tensor-network methods, the partition function of the 2D classical model is expressed as a product of 1D quantum transfer operator, whose eigenequation can be solved by an algorithm of matrix product states rigorously. From the singularity shown by the entanglement entropy of the 1D quantum analog, various phase transitions can be accurately determined. Below the BKT phase transition, an interlayer Ising long-range order is established at T_{Ising}, and the phase coherence of both intralayers and interlayers is locked together. For two identical layers, the Ising transition coincides with the BKT transition at a multicritical point. For two inequivalent layers, however, there emerges an intermediate quasi-long-range order phase (T_{Ising}

14.
Open Med (Wars) ; 16(1): 1378-1385, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595351

RESUMO

AIM: Renal fibrosis (RF) is a common clinical condition leading to irreversible renal function loss. Tyrosine kinase proteins and microRNAs (miRs) are associated with pathogenesis and we aim to investigate the role of Fer and its partner miR(s) in RF. METHOD: In silico reproduction of Mouse Kidney FibrOmics browser was performed to identify potential miR(s) and target gene(s). In vivo validation was performed in C57BL/6 mice with unilateral ureteral obstruction (UUO). In vitro validation was performed in rat kidney fibroblast NRK-49F cells. Mimics and inhibitors of miR-29c-3p were constructed. The target gene Fer was monitored by RT-PCR and western blotting. The levels of interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α in serum and media were measured by ELISA. RESULTS: The Fer expression and protein level were gradually increased during 14 days of UUO modeling. miR-29c-3p expression was strongly correlated with that of Fer. In vivo validation showed increased expressions of fibrosis-associated genes and increased phospoho-Smad3 level in the UUO model. Fer-knockdown (KD) significantly decreased expressions of fibrosis-associated genes. Pharmaceutical inhibition of Fer showed similar effects to miR-29c-3p, and miR inhibition showed a significant decrease of excretion of inflammatory factors. CONCLUSION: Dysregulation of miR-29c-3p and Fer plays a role in RF. Pharmaceutical or genetic inhibition of Fer may serve as the potential treatment for RF.

15.
Gen Physiol Biophys ; 40(2): 147-154, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33881001

RESUMO

Renal fibrosis poses critical health problem. We aimed to investigate role of let-7i-5p in renal fibrosis. In silico reproduction of Mouse Kidney FibrOmics browser was used to identify potential target of let-7i-5p. In vivo validation was conducted in C57BL/6 mice with unilateral ureteral obstruction (UUO) and folic acid (FA) induction. In vitro validation was performed in transforming growth factor (TGF)-ß1-treated HK-2 cells. Mimics and inhibitors of let-7i-5p, and target gene polypeptide N-acetylgalactosaminyltransferase 1 (GALNT1) were monitored by RT-PCR and Western blotting. Fibrosis markers, injury markers, and house-keeping genes were evaluated. Levels of interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α in serum and media were measured by ELISA. In silico analysis showed gradual increase of let-7i-5p and decrease of GALNT1 over time and the combination was validated both in mouse and human miR-gene target prediction databases. Expression of GALNT1 decreased while expression of let-7i-5p increased in renal tissues of both UUO and FA mice. Serum IL-6, IL-1ß, and TNF-α levels were elevated in vivo. In vitro models revealed negative correlation between expression levels of let-7i-5p and GALNT1. Overexpression of let-7i-5p inhibited GALNT1 expression and reduced release of inflammatory factors. In conclusion, overexpression of GALNT1 may combat the inflammation induced by let-7i-5p.


Assuntos
Nefropatias , MicroRNAs , Animais , Fibrose , Rim/patologia , Nefropatias/genética , Nefropatias/patologia , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética
16.
Phys Rev Lett ; 124(18): 186602, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32441947

RESUMO

We report theoretical and experimental analyses of the thermal Hall conductivity in correlated systems. For both fermionic and bosonic excitations with nontrivial topology, we show that at "intermediate" temperatures, the thermal Hall conductivity exhibits an unexpected universal scaling with a simple exponential form. At low temperatures, it behaves differently and reflects the spectral properties of underlying excitations. Our predictions are examined as examples in two prototype compounds, the quantum paraelectric SrTiO_{3} and the spin-liquid compound RuCl_{3}. The experimental data can be largely covered by our proposed minimal phenomenological model independent of microscopic details, revealing dominant bosonic contributions in SrTiO_{3} and gapped fermionic excitations in RuCl_{3}. Our work establishes a phenomenological link between microscopic models and experimental data and provides a unified basis for analyzing the thermal Hall conductivity in correlated systems over a wide temperature region.

17.
Phys Rev Lett ; 124(13): 130603, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32302160

RESUMO

The non-Abelian topological phase with Fibonacci anyons minimally supports universal quantum computation. In order to investigate the possible phase transitions out of the Fibonacci topological phase, we propose a generic quantum-net wave function with two tuning parameters dual with each other, and the norm of the wave function can be exactly mapped into a partition function of the two-coupled ϕ^{2}-state Potts models, where ϕ=(sqrt[5]+1)/2 is the golden ratio. By developing the tensor network representation of this wave function on a square lattice, we can accurately calculate the full phase diagram with the numerical methods of tensor networks. More importantly, it is found that the non-Abelian Fibonacci topological phase is enclosed by three distinct nontopological phases and their dual phases of a single ϕ^{2}-state Potts model: the gapped dilute net phase, critical dense net phase, and spontaneous translation symmetry breaking gapped phase. We also determine the critical properties of the phase transitions among the Fibonacci topological phase and those nontopological phases.

18.
Front Neurol ; 11: 81, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161563

RESUMO

Paroxysmal sympathetic hyperactivity (PSH) has predominantly been described after traumatic brain injury (TBI), which is associated with hyperthermia, hypertension, tachycardia, tachypnea, diaphoresis, dystonia (hypertonia or spasticity), and even motor features such as extensor/flexion posturing. Despite the pathophysiology of PSH not being completely understood, most researchers gradually agree that PSH is driven by the loss of the inhibition of excitation in the sympathetic nervous system without parasympathetic involvement. Recently, advances in the clinical and diagnostic features of PSH in TBI patients have reached a broad clinical consensus in many neurology departments. These advances should provide a more unanimous foundation for the systematic research on this clinical syndrome and its clear management. Clinically, a great deal of attention has been paid to the definition and diagnostic criteria, epidemiology and pathophysiology, symptomatic treatment, and prevention and control of secondary brain injury of PSH in TBI patients. Potential benefits of treatment for PSH may result from the three main goals: eliminating predisposing causes, mitigating excessive sympathetic outflow, and supportive therapy. However, individual pathophysiological differences, therapeutic responses and outcomes, and precision medicine approaches to PSH management are varied and inconsistent between studies. Further, many potential therapeutic drugs might suppress manifestations of PSH in the process of TBI treatment. The purpose of this review is to present current and comprehensive studies of the identification of PSH after TBI in the early stage and provide a framework for symptomatic management of TBI patients with PSH.

19.
Huan Jing Ke Xue ; 40(9): 3982-3989, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854860

RESUMO

Nitrogen oxide (NOx) is an important precursor for many air pollution problems such as fine particulate matter and ground-level ozone. Because air pollution levels increase daily, it is important to control NOx emissions from industrial boiler flue gas. A series of different Co3O4 catalysts was prepared in this study by different methods. The effects of the preparation methods on selective catalytic reduction of NO by CO (CO-SCR) were investigated. The catalysts were characterized by BET, XRD, HR-TEM, and Raman. The results show that the Co3O4-S catalyst, prepared by solid grinding with cobalt sulfate as the precursor, had better CO-SCR activity and H2O resistance and that Co3O4-C, prepared by solid grinding with cobalt acetate as the precursor, showed excellent H2O resistance. The NO oxidation results showed that better NO oxidation activity over the catalysts is an important reason for the improved CO-SCR activity. The Raman results indicate that more Co2+ ions appeared on the surface of Co3O4-S, which benefited the formation of oxygen vacancies. The H2-TPR results showed better redox property of the Co3O4-S catalyst. The HR-TEM results shoes that the (111) and (220) crystal planes were exposed mainly on Co3O4-S and Co3O4-O and that more (220) crystal planes are conducive to improved reaction.

20.
Orthop Surg ; 11(6): 1201-1208, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31773895

RESUMO

OBJECTIVE: To determine the value of Böhler's angle (BA) in a group of Chinese people, analyze possible factors that influence it, and compare BA with that in previous literature. METHODS: A total of 143 cases, aged from 4 to 79 years, were enrolled in the study, including 64 males and 79 females (79 left feet and 64 right feet). Radiographs were independently measured by six observers. Age, sex, body side, subtalar joint congruity (STJC), and X-beam obliquity (TT) were recorded. The database was assessed based on intraobserver agreement, data distribution, the randomness of case selection, and the ratio equality of binomial variables. Then, the normal value of BA was established, as well as the correlation between BA and other parameters. RESULTS: In the present study, the interobserver reliability of BA, STJC, and TT was excellent. The BA data revealed a normal distribution, and the randomness of case selection was verified for age, sex, and body side. The ratio of sex and body side was equal. Homogeneity of variance was observed when comparing the value of BA between different groups. The value of BA was 31.6° ± 5.19° (range, 20.08°-47.19°), which was not related to age, sex, body side, and minor X-ray beam obliquity. BA application was not suitable for individuals younger than 10 years. The mean value of BA in this study was not identical with those in previous reports. This demonstrated that BA varies for different races. CONCLUSION: For Chinese people, 30° to 33° is recommended as the target value of BA for calcaneal fracture reduction, except in children under 10 years of age.


Assuntos
Calcâneo/diagnóstico por imagem , Calcâneo/lesões , Fraturas Intra-Articulares/diagnóstico por imagem , Articulação Talocalcânea/diagnóstico por imagem , Tálus/diagnóstico por imagem , Adolescente , Adulto , Idoso , Povo Asiático , Criança , Pré-Escolar , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Reprodutibilidade dos Testes , Adulto Jovem
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