RESUMO
Perovskite light-emitting diodes (PeLEDs) with an external quantum efficiency exceeding 20% have been achieved in both green and red wavelengths1-5; however, the performance of blue-emitting PeLEDs lags behind6,7. Ultrasmall CsPbBr3 quantum dots are promising candidates with which to realize efficient and stable blue PeLEDs, although it has proven challenging to synthesize a monodispersed population of ultrasmall CsPbBr3 quantum dots, and difficult to retain their solution-phase properties when casting into solid films8. Here we report the direct synthesis-on-substrate of films of suitably coupled, monodispersed, ultrasmall perovskite QDs. We develop ligand structures that enable control over the quantum dots' size, monodispersity and coupling during film-based synthesis. A head group (the side with higher electrostatic potential) on the ligand provides steric hindrance that suppresses the formation of layered perovskites. The tail (the side with lower electrostatic potential) is modified using halide substitution to increase the surface binding affinity, constraining resulting grains to sizes within the quantum confinement regime. The approach achieves high monodispersity (full-width at half-maximum = 23 nm with emission centred at 478 nm) united with strong coupling. We report as a result blue PeLEDs with an external quantum efficiency of 18% at 480 nm and 10% at 465 nm, to our knowledge the highest reported among perovskite blue LEDs by a factor of 1.5 and 2, respectively6,7.
RESUMO
Tracheopericardial fistula is an extremely rare clinical condition caused by lung disease penetrating the tracheal wall and extending to the pericardial cavity, forming a fistula between the airway and the pericardial cavity. Since the pericardial cavity communicates with the respiratory tract, gases, airway secretions and pathogens can enter the cavity, leading to pneumopericardium, effusion and abscess. In severe cases, it can result in cardiac tamponade and cardiogenic shock. Only a few cases of TPF have been reported in the literature. In this report, a 72-year-old man with recurrent lung cancer presented with fever, chest tightness and chest pain. Electrocardiogram showed ST-segment elevation in multiple leads, resembling an acute myocardial infarction. Emergency coronary angiography did not reveal significant stenosis. Further examination with chest computed tomography and bronchoscopy revealed pericardial effusion and a tracheal fistula, leading to the final diagnosis of TPF as a complication of lung cancer. This case aims to enhance understanding and recognition of this clinical entity to reduce misdiagnosis.
Assuntos
Neoplasias Pulmonares , Infarto do Miocárdio , Humanos , Masculino , Idoso , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/diagnóstico , Infarto do Miocárdio/diagnóstico , Diagnóstico Diferencial , Derrame Pericárdico/etiologia , Derrame Pericárdico/diagnóstico , Doenças da Traqueia/diagnóstico , Doenças da Traqueia/diagnóstico por imagem , Doenças da Traqueia/complicações , Tomografia Computadorizada por Raios X , Pericárdio/patologia , Pericárdio/diagnóstico por imagem , Broncoscopia , Fístula/diagnóstico , EletrocardiografiaRESUMO
Metal halide perovskites are promising candidates for γ-ray spectrum detectors. However, achieving high-resolution energy spectra in single-photon pulse-height analysis mode remains challenging, due to the inevitable leakage currents degrade the recognizable fingerprint energies which is critical for resolving γ-ray spectroscopy. We demonstrate under high bias voltage, a deficient contact barrier can lead to excessive surface charge injection, thereby increasing leakage current from electrodes to perovskites. Hence, we conceive to employ surface ligand engineering on perovskite single crystals to manipulate energy levels to suppress leakage current. In particular, anchoring a strong dipole ligand onto the perovskite induced surface charge-density displacement, leading to a downward band bending and heightened the corresponding contact barrier. Consequently, the strategy minimized the detectors'leakage current by an order of magnitude, to as low as 44 nA cm-2. The resulting detectors show a significant improvement in energy resolution, 3.9% for 22Na 511 keV γ-rays has been achieved at room temperature. The resulting detector further resolves each fingerprint energy for 152Eu γ-spectrum, representing one of the best γ-rays perovskite detectors reported to date. Moreover, the detectors exhibited stabilized energy resolution without any degradation under a continuous electric field for over 300 minutes, representing the longest longevity reported to date.
RESUMO
Precise manipulation of the coordination environment of single-atom catalysts (SACs), particularly the simultaneous engineering of multiple coordination shells, is crucial to maximize their catalytic performance but remains challenging. Herein, we present a general two-step strategy to fabricate a series of hollow carbon-based SACs featuring asymmetric Zn-N2 O2 moieties simultaneously modulated with S atoms in higher coordination shells of Zn centers (n≥2; designated as Zn-N2 O2 -S). Systematic analyses demonstrate that the synergetic effects between the N2 O2 species in the first coordination shell and the S atoms in higher coordination shells lead to robust discrete Zn sites with the optimal electronic structure for selective O2 reduction to H2 O2 . Remarkably, the Zn-N2 O2 moiety with S atoms in the second coordination shell possesses a nearly ideal Gibbs free energy for the key OOH* intermediate, which favors the formation and desorption of OOH* on Zn sites for H2 O2 generation. Consequently, the Zn-N2 O2 -S SAC exhibits impressive electrochemical H2 O2 production performance with high selectivity of 96 %. Even at a high current density of 80â mA cm-2 in the flow cell, it shows a high H2 O2 production rate of 6.924â mol gcat -1 h-1 with an average Faradaic efficiency of 93.1 %, and excellent durability over 65â h.
RESUMO
NiCo2 O4 nanowire array on carbon cloth (NiCo2 O4 /CC) is proposed as a highly active electrocatalyst for ambient nitrate (NO3 - ) reduction to ammonia (NH3 ). In 0.1 m NaOH solution with 0.1 m NaNO3 , such NiCo2 O4 /CC achieves a high Faradic efficiency of 99.0% and a large NH3 yield up to 973.2 µmol h-1 cm-2 . The superior catalytic activity of NiCo2 O4 comes from its half-metal feature and optimized adsorption energy due to the existence of Ni in the crystal structure. A Zn-NO3 - battery with NiCo2 O4 /CC cathode also shows a record-high battery performance.
RESUMO
Physicochemical confinement and catalytic conversion of lithium polysulfides (LiPSs) are crucial to suppress the shuttle effect and enhance the redox kinetics of lithium-sulfur (Li-S) batteries. In this study, a NH4 Cl-assisted pyrolysis strategy is developed to fabricate highly mesoporous N-rich carbon (designed as NC(p)) featuring thin outer shells and porous inner networks, on which single-Ni atoms are anchored to form an excellent sulfur host (designed as Ni-NC(p)) for Li-S batteries. During pyrolysis, the pyrolytic HCl from confined NH4 Cl within ZIF-8 will in situ etch ZIF-8 to produce rich mesoporous in the carbonized product NC(p). The mesoporous Ni-NC(p) enables favorable electron/ion transfer, high sulfur loading, and effective confinement of LiPSs, while the catalytic effect of single-Ni species enhances the redox kinetics of LiPSs. As a result, the sulfur cathode based on the Ni-NC(p) host delivers obviously improved Li-S battery performance with high specific capacity, good rate capability, and cycling stability.
RESUMO
The unique structural characteristics of one-dimensional (1D) hollow nanostructures result in intriguing physicochemical properties and wide applications, especially for electrochemical energy storage applications. In this Minireview, we give an overview of recent developments in the rational design and engineering of various kinds of 1D hollow nanostructures with well-designed architectures, structural/compositional complexity, controllable morphologies, and enhanced electrochemical properties for different kinds of electrochemical energy storage applications (i.e. lithium-ion batteries, sodium-ion batteries, lithium-sulfur batteries, lithium-selenium sulfur batteries, lithium metal anodes, metal-air batteries, supercapacitors). We conclude with prospects on some critical challenges and possible future research directions in this field. It is anticipated that further innovative studies on the structural and compositional design of functional 1D nanostructured electrodes for energy storage applications will be stimulated.
RESUMO
Exploring earth-abundant electrocatalysts with excellent activity, robust stability, and multiple functions is crucial for electrolytic hydrogen generation. Porous phosphorized CoNi2 S4 yolk-shell spheres (P-CoNi2 S4 YSSs) were rationally designed and synthesized by a combined hydrothermal sulfidation and gas-phase phosphorization strategy. Benefiting from the strengthened Ni3+ /Ni2+ couple, enhanced electronic conductivity, and hollow structure, the P-CoNi2 S4 YSSs exhibit excellent activity and durability towards hydrogen/oxygen evolution and urea oxidation reactions in alkaline solution, affording low potentials of -0.135â V, 1.512â V, and 1.306â V (versus reversible hydrogen electrode) at 10â mA cm-2 , respectively. Remarkably, when used as the anode and cathode simultaneously, the P-CoNi2 S4 catalyst merely requires a cell voltage of 1.544â V in water splitting and 1.402â V in urea electrolysis to attain 10â mA cm-2 with excellent durability for 100â h, outperforming most of the reported nickel-based sulfides and even noble-metal-based electrocatalysts. This work promotes the application of sulfides in electrochemical hydrogen production and provides a feasible approach for urea-rich wastewater treatment.
RESUMO
Electrochemical reduction of NO not only offers an attractive alternative to the Haber-Bosch process for ambient NH3 production but mitigates the human-caused unbalance of nitrogen cycle. Herein, we report that MoS2 nanosheet on graphite felt (MoS2 /GF) acts as an efficient and robust 3D electrocatalyst for NO-to-NH3 conversion. In acidic electrolyte, such MoS2 /GF attains a maximal Faradaic efficiency of 76.6 % and a large NH3 yield of up to 99.6â µmol cm-2 h-1 . Using MoS2 nanosheet-loaded carbon paper as the cathode, a proof-of-concept device of Zn-NO battery was assembled to deliver a discharge power density of 1.04â mW cm-2 and an NH3 yield of 411.8â µg h-1 mgcat. -1 . Calculations reveal that the positively charged Mo-edge sites facilitate NO adsorption/activation via an acceptance-donation mechanism and disfavor the binding of protons and the coupling of N-N bond.
RESUMO
There has been extensive research into lithium-rich layered oxide materials as candidates for the nextgeneration of cathode materials in lithium-ion batteries, due to their high energy density and low cost; however, their poor cycle life and fast voltage fade hinder their large-scale commercial application. Here, we propose a novel cation/anion (Na+/PO4 3-) co-doping approach to mitigate the discharge capacity and voltage fade of a Co-free Li1.2Ni0.2Mn0.6O2 cathode. Our results show that the synergistic effect of cation/anion doping can promote long cycle stability and rate performance by inhibiting the phase transformation of the layered structure to a spinel or rock-salt structure and stabilizing the well-ordered crystal structure during long cycles. The co-doped sample exhibits an outstanding cycle stability (capacity retention of 86.7% after 150 cycles at 1 C) and excellent rate performance (153 mAh g-1 at 5 C). The large ionic radius of Na+ can expand the Li slab to accelerate Li diffusion and the large tetrahedral PO4 3- polyanions with high electronegativity stabilize the local structure to improve the electrochemical performance.
RESUMO
The construction of hybrid architectures for electrode materials has been demonstrated as an efficient strategy to boost sodium-storage properties because of the synergetic effect of each component. However, the fabrication of hybrid nanostructures with a rational structure and desired composition for effective sodium storage is still challenging. In this study, an integrated nanostructure composed of copper-substituted CoS2 @Cux S double-shelled nanoboxes (denoted as Cu-CoS2 @Cux S DSNBs) was synthesized through a rational metal-organic framework (MOF)-based templating strategy. The unique shell configuration and complex composition endow the Cu-CoS2 @Cux S DSNBs with enhanced electrochemical performance in terms of superior rate capability and stable cyclability.
RESUMO
Hybrid materials, integrating the merits of individual components, are ideal structures for efficient sodium storage. However, the construction of hybrid structures with decent physical/electrochemical properties is still challenging. Now, the elaborate design and synthesis of hierarchical nanoboxes composed of three-layered Cu2 S@carbon@MoS2 as anode materials for sodium-ion batteries is reported. Through a facile multistep template-engaged strategy, ultrathin MoS2 nanosheets are grown on nitrogen-doped carbon-coated Cu2 S nanoboxes to realize the Cu2 S@carbon@MoS2 configuration. The design shortens the diffusion path of electrons/Na+ ions, accommodates the volume change of electrodes during cycling, enhances the electric conductivity of the hybrids, and offers abundant active sites for sodium uptake. By virtue of these advantages, these three-layered Cu2 S@carbon@MoS2 hierarchical nanoboxes show excellent electrochemical properties in terms of decent rate capability and stable cycle life.
RESUMO
We report the synthesis of cobalt sulfide multi-shelled nanoboxes through metal-organic framework (MOF)-based complex anion conversion and exchange processes. The polyvanadate ions react with cobalt-based zeolitic imidazolate framework-67 (ZIF-67) nanocubes to form ZIF-67/cobalt polyvanadate yolk-shelled particles. The as-formed yolk-shelled particles are gradually converted into cobalt divanadate multi-shelled nanoboxes by solvothermal treatment. The number of shells can be easily controlled from 2 to 5 by varying the temperature. Finally, cobalt sulfide multi-shelled nanoboxes are produced through ion-exchange with S2- ions and subsequent annealing. The as-obtained cobalt sulfide multi-shelled nanoboxes exhibit enhanced sodium-storage properties when evaluated as anodes for sodium-ion batteries. For example, a high specific capacity of 438â mAh g-1 can be retained after 100â cycles at the current density of 500â mA g-1 .
RESUMO
We have designed and synthesized novel hollow Ni/Fe layered double hydroxide (LDH) polyhedrons as an advanced sulfur host for enhancing the performance of lithium-sulfur (Li-S) batteries. The Ni/Fe LDH host shows multiple advantages. First, the Ni/Fe LDH shells can provide sufficient sulfiphilic sites for chemically bonding with polysulfides. Second, the hollow architecture can provide sufficient inner space for both loading a large amount of sulfur and accommodating its large volumetric expansion. Moreover, once the active material is confined within the host, the shells could easily restrict the outward diffusion of polysulfides, guaranteeing prolonged cycle life even with high sulfur loading. As a result, the S@Ni/Fe LDH cathode has successfully solved the main issues related to sulfur electrodes, and it exhibits significantly improved electrochemical performances with prolonged life over 1000â cycles and excellent rate properties.
RESUMO
Pulmonary fibrosis (PF) is a disease with an unknown cause and a poor prognosis. In this study, we aimed to explore the pathogenesis of PF and the mechanism of sulindac in attenuating bleomycin (BLM)-induced PF. The rat PF model was induced by BLM and verified through histological studies and hydroxyproline assay. The severity of BLM-induced PF in rats and other effects, such as the extent of the wet lung to bw ratios, thickening of alveolar interval or collagen deposition, was obviously ameliorated in sulindac-treated rat lungs compared with BLM-induced lungs. Sulindac also reversed the epithelial mesenchymal transition (EMT) and inhibited the PF process by restoring the levels of E-cadherin and α-smooth muscle actin (SMA) in A549 cells. Our results further demonstrated that the above effects of sulindac might be related to regulating of interferon gamma (IFN-γ) expression, which further affects signal transducers and activators of transcription 3 (STAT3) and phosphorylated STAT3 (p-STAT3) levels. Moreover, higher miR-21 levels with the decreased E-cadherin and increased α-SMA expressions were found in transforming growth factor-ß1-treated A549 cells, which can be reversed by sulindac. Collectively, our results demonstrate that by decreasing IFN-γ-induced STAT3/p-STAT3 expression to down-regulate miR-21, sulindac could significantly reverse EMT in A549 cells and prevent BLM-induced PF.
Assuntos
Pulmão/efeitos dos fármacos , MicroRNAs/genética , Fibrose Pulmonar/prevenção & controle , Fator de Transcrição STAT3/metabolismo , Sulindaco/farmacologia , Actinas/metabolismo , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Bleomicina , Western Blotting , Caderinas/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Interferon gama/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Microscopia de Fluorescência , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/genética , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacosRESUMO
New phenanthroline derivatives (1, 2, 3, 4) containing phenol groups have been synthesized and optimized. The nano-material of compound 2 was also developed. Their binding properties were evaluated for various biological anions (F(-), Cl(-), Br(-), I(-), AcO(-) and H(2)PO(4)(-)) by theoretical investigation, UV-vis, fluorescence, (1)HNMR titration experiments and these compounds all showed strong binding ability for AcO(-) without the interference of other anions tested. The anion binding ability could be regularized by electron push-pull properties of the ortho- or para- substituent on benzene. Theoretical investigation analysis revealed the effect of intramolecular hydrogen bond existed between -OH and other atoms in the structure of these compounds.
Assuntos
Acetatos/química , Nanoestruturas/química , Fenantrolinas/química , Teoria Quântica , Ânions/química , Estrutura Molecular , Tamanho da Partícula , Fenantrolinas/síntese química , Propriedades de SuperfícieRESUMO
Background: There is a growing interest in the use of complementary therapies for the prevention of disease and the maintenance of health. Furthermore, complementary therapies that incorporate exercise are becoming increasingly prevalent among the older adult, and thus may represent a crucial strategy for the primary and secondary prevention of cardiovascular disease (CVD). Exercise therapy, as a means to prevent and treat cardiovascular diseases, has been gradually applied in clinical practice. It has the advantages of reducing mortality, improving clinical symptoms, restoring physical function and improving quality of life. In recent years, traditional Chinese sports such as Ba Duan Jin and Qigong have developed rapidly. Therefore, a comprehensive systematic review is required to examine interventions involving Ba Duan Jin exercise in healthy adults or those at increased risk of CVD in order to determine the effectiveness of Ba Duan Jin exercise for the primary prevention of CVD. Objective: To investigate the effect of Ba Duan Jin exercise intervention for the primary prevention of cardiovascular diseases. Methods: Eight databases were systematically searched from inception to July, 2024 for randomized controlled trials (RCTs) to evaluated the impact of Ba Duan Jin exercise intervention on cardiovascular diseases. The search terms were "Cardiovascular diseases" "Ba Duan Jin" and "Randomized controlled." The Cochrane risk assessment tool was used to evaluate the study quality, and the meta-analysis was performed using Rev. Man 5.4 software. Results: Seventeen completed trials were conducted with 1,755 participants who were randomly assigned and met the inclusion criteria. All 17 studies were conducted in China. The meta-analysis indicates that Ba Duan Jin exercise therapy can provide long-term benefits (20-30 years) by reducing all-cause mortality (RR = 0.55, 95% CI: 0.44-0.68, p < 0.01) and stroke mortality (RR = 0.49, 95% CI: 0.36-0.66, p < 0.01) in hypertensive patients. Subgroup analyses reveal that Ba Duan Jin exercise therapy decreases SBP (MD = -4.05, 95% CI = -6.84 to -1.26, p < 0.01) and DBP (MD = -3.21, 95% CI = -5.22 to -1.20, p < 0.01) levels in patients with essential hypertension, significantly reduces serum TC (MD = -0.78, 95% CI = -1.06 to -0.50, p < 0.01), TG (MD = -0.78, 95% CI = -0.93 to -0.62, p < 0.01), and LDL-C (MD = -0.76, 95% CI = -0.92 to -0.60, p < 0.01) levels in patients with hyperlipidemia, increases HDL-C (MD = 0.32, 95% CI = 0.14-0.51, p < 0.01) levels, and produces beneficial effects on cardiovascular function. Additionally, it can alleviate anxiety (MD = -3.37, 95% CI = -3.84 to -2.89, p < 0.01) and improve sleep quality (MD = -2.68, 95% CI = -3.63to -1.73, p < 0.01). Conclusion: Ba Duan Jin exercise therapy can improve the physical and mental condition and quality of life of patients with cardiovascular diseases, and it is worthy of further promotion and application in clinical practice. Systematic review registration: PROSPERO, identifier: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024496934.
Assuntos
Doenças Cardiovasculares , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Doenças Cardiovasculares/prevenção & controle , Terapia por Exercício , Qigong , Masculino , Qualidade de Vida , Pessoa de Meia-Idade , Prevenção Primária , Adulto , FemininoRESUMO
Objective: Psoralea corylifolia L. (FP) has received increasing attention due to its potential hepatotoxicity. Methods: In this study, zebrafish were treated with different concentrations of an aqueous extract of FP (AEFP; 40, 50, or 60 µg/mL), and the hepatotoxic effects of tonicity were determined by the mortality rate, liver morphology, fluorescence area and intensity of the liver, biochemical indices, and pathological tissue staining. The mRNA expression of target genes in the bile acid metabolic signaling pathway and lipid metabolic pathway was detected by qPCR, and the mechanism of toxicity was initially investigated. AEFP (50 µg/mL) was administered in combination with FXR or a peroxisome proliferator-activated receptor α (PPARα) agonist/inhibitor to further define the target of toxicity. Results: Experiments on toxic effects showed that, compared with no treatment, AEFP administration resulted in liver atrophy, a smaller fluorescence area in the liver, and a lower fluorescence intensity (p < 0.05); alanine transaminase (ALT), aspartate transaminase (AST), and γ-GT levels were significantly elevated in zebrafish (p < 0.01), and TBA, TBIL, total cholesterol (TC), TG, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels were elevated to different degrees (p < 0.05); and increased lipid droplets in the liver appeared as fatty deposits. Molecular biological validation revealed that AEFP inhibited the expression of the FXR gene, causing an increase in the expression of the downstream genes SHP, CYP7A1, CYP8B1, BSEP, MRP2, NTCP, peroxisome proliferator-activated receptor γ (PPARγ), ME-1, SCD-1, lipoprotein lipase (LPL), CPT-1, and CPT-2 and a decrease in the expression of PPARα (p < 0.05). Conclusion: This study demonstrated that tonic acid extracts are hepatotoxic to zebrafish through the inhibition of FXR and PPARα expression, thereby causing bile acid and lipid metabolism disorders.
RESUMO
Objective: To investigate the clinical features of active tuberculosis (TB) infection due to immune checkpoint inhibitors (ICIs) treatment in patients with advanced cancer. Methods: We report the diagnosis and treatment of a case of pulmonary malignancy (squamous cell carcinoma, cT4N3M0 IIIC), secondary to active TB infection following ICIs therapy. Moreover, we summarize and analyze other related cases collected from the China National Knowledge Infrastructure (CNKI), Wanfang Database, PubMed, the Web of Science, and EMBASE (up to October 2021). Results: A total of 23 patients, including 20 males and 3 females who were aged 49-87 years with a median age of 65 years, were included in the study. Twenty-two patients were diagnosed by Mycobacterium tuberculosis culture or DNA polymerase chain reaction (PCR), while the remaining patient was diagnosed by tuberculin purified protein derivative and pleural biopsy. One case had an interferon-gamma release assay (IGRA) to rule out latent TB infection prior to the application of ICI. Fifteen patients received an anti-tuberculosis regimen. Among the 20 patients with a description of clinical regression, 13 improved and 7 died. Seven of the patients who improved were treated with ICI again and four of them did not experience a recurrence or worsening of TB. The case diagnosed in our hospital also improved after receiving anti-TB treatment after stopping ICI therapy, and continued chemotherapy on the basis of anti-TB treatment, and his condition is relatively stable at present. Conclusion: Due to the lack of specificity of TB infection following ICIs therapy, patients should be followed for fever and respiratory symptoms for 6.3 months after drug administration. It is recommended that IGRA should be performed before ICIs therapy and the development of TB during immunotherapy in patients who are positive in IGRA should be closely monitored. The symptoms of TB in most patients can be improved with ICIs withdrawal and anti-TB treatment, but there is still a need to be alert to the potentially fatal risk of TB.