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Simultaneous enhancement of free excitons (FEs) emission and self-trapped excitons (STEs) emission remains greatly challenging because of the radiative pathway competition. Here, a significant fluorescence improvement, associated with the radiative recombination of both FEs and STEs is firstly achieved in an unconventional ACI-type hybrid perovskite, (ACA)(MA)PbI4 (ACA=acetamidinium) crystals with {PbI6} octahedron units, through hydrostatic pressure processing. Note that (ACA)(MA)PbI4 exhibits a 91.5-fold emission enhancement and considerable piezochromism from green to red in a mild pressure interval of 1 atm to 2.5 GPa. The substantial distortion of both individual halide octahedron and the Pb-I-Pb angles between two halide octahedra under high pressure indeed determines the pressure-tuning localized excitons behavior. Upon higher pressure, photocurrent enhancement is also observed, which is attributed to the promoted electronic connectivity in (ACA)(MA)PbI4. The anisotropic compaction reduces the distance between neighboring organic molecules and {PbI6} octahedra, leading to the enhancement of hydrogen bonding interactions. This work not only offers a deep understanding of the structure-optical relationships of ACI-type perovskites, but also presents insights into breaking the limits of luminescent efficiency by pressure-suppressed nonradiative recombination.
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BACKGROUND: Synovitis, characterized by inflammation of the synovial membrane, is commonly induced by meniscus tears. However, significant differences in inflammatory responses and the key inflammatory mediators of synovium induced by different types of meniscal tears remain unclear. METHODS: Magnetic resonance imaging (MRI) was employed to identify the type of meniscus tear, and the quantification of synovial inflammation was assessed through H&E staining assay. Transcription and expression levels of IL-1ß and IL-6 were evaluated using bioinformatics, ELISA, RT-qPCR, and IHC of CD68 staining assays. The therapeutic potential of Docosapentaenoic Acid (DPA) was determined through network pharmacology, ELISA, and RT-qPCR assays. The safety of DPA was assessed using colony formation and EdU staining assays. RESULTS: The results indicate that both IL-1ß and IL-6 play pivotal roles in synovitis pathogenesis, with distinct expression levels across various subtypes. Among tested meniscus tears, oblique tear and bucket handle tear induced the most severe inflammation, followed by radial tear and longitudinal tear, while horizontal tear resulted in the least inflammation. Furthermore, in synovial inflammation induced by specific meniscus tears, the anterior medial tissues exhibited significantly higher local inflammation than the anterior lateral and suprapatellar regions, highlighting the clinical relevance and practical guidance of anterior medial tissues' inflammatory levels. Additionally, we identified the essential omega-3 fatty acid DPA as a potential therapeutic agent for synovitis, demonstrating efficacy in blocking the transcription and expression of IL-1ß and IL-6 with minimal side effects. CONCLUSION: These findings provide valuable insights into the nuanced nature of synovial inflammation induced by various meniscal tear classifications and contribute to the development of new adjunctive therapeutic agents in the management of synovitis.
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Ácidos Grasos Insaturados , Interleucina-1beta , Imagen por Resonancia Magnética , Membrana Sinovial , Sinovitis , Lesiones de Menisco Tibial , Lesiones de Menisco Tibial/tratamiento farmacológico , Lesiones de Menisco Tibial/metabolismo , Sinovitis/tratamiento farmacológico , Sinovitis/metabolismo , Sinovitis/patología , Membrana Sinovial/efectos de los fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Humanos , Ácidos Grasos Insaturados/farmacología , Ácidos Grasos Insaturados/metabolismo , Ácidos Grasos Insaturados/uso terapéutico , Masculino , Interleucina-1beta/metabolismo , Animales , Interleucina-6/metabolismo , Femenino , Meniscos Tibiales/efectos de los fármacos , Meniscos Tibiales/metabolismo , Ratones , Modelos Animales de EnfermedadRESUMEN
Lead-free organic-inorganic hybrid perovskites are one class of promising optoelectronic materials that have attracted much attention due to their outstanding stability and environmentally friendly nature. However, the intrinsic band gap far from the Shockley-Queisser limit and the inferior electrical properties largely limit their applicability. Here, a considerable band-gap narrowing from 2.43 to 1.64 eV with the compression rate up to 32.5% is achieved via high-pressure engineering in the lead-free hybrid perovskite MA3Sb2I9. Meanwhile, the electric transport process changes from the initial interaction of both ions and electrons to only the contribution of electrons upon compression. The alteration in electrical characteristics is ascribed to the vibration limitation of organic ions and the enhanced orbital overlap, resulting from the reduction of the Sb-I bond length through pressure-induced phase transitions. This work not only systematically investigates the correlation between the structural and optoelectronic properties of MA3Sb2I9 but also provides a potential pathway for optimizing electrical properties in lead-free hybrid perovskites.
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Transition metal dichalcogenides (TMDs) exhibit excellent electronic and photoelectric properties under pressure, prompting researchers to investigate their structural phase transitions, electrical transport, and photoelectric response upon compression. Herein, the structural and photoelectric properties of layered ZrS2 under pressure using in situ high-pressure photocurrent, Raman scattering spectroscopy, alternating current impedance spectroscopy, absorption spectroscopy, and theoretical calculations are studied. The experimental results show that the photocurrent of ZrS2 continuously increases with increasing pressure. At 24.6 GPa, the photocurrent of high-pressure phase P21/m is three orders of magnitude greater than that of the initial phase P 3 ¯ m 1 $P\bar{3}m1$ at ambient pressure. The minimum synthesis pressure for pure high-pressure phase P21/m of ZrS2 is 18.8 GPa, which exhibits a photocurrent that is two orders of magnitude higher than that of the initial phase P 3 ¯ m 1 $P\bar{3}m1$ and displays excellent stability. Additionally, it is discovered that the crystal structure, electrical transport properties and bandgap of layered ZrS2 can also be regulated by pressure. This work offers researchers a new direction for synthesizing high-performance TMDs photoelectric materials using high pressure, which is crucial for enhancing the performance of photoelectric devices in the future.
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This work investigates the impact of pressure on the structural, optical properties, and electronic structure of CsPbBr3 quantum dots (QDs) using steady-state photoluminescence, steady-state absorption, and femtosecond transient absorption spectroscopy, reaching a maximum pressure of 3.38 GPa. The experimental results indicate that CsPbBr3 QDs undergo electronic state (ES) transitions from ES-I to ES-II and ES-II to ES-III at 0.38 and 1.08 GPa, respectively. Intriguingly, a mixed state of ES-II and ES-III is observed within the pressure range of 1.08-1.68 GPa. The pressure-induced fluorescence quenching in ES-II is attributed to enhanced defect trapping and reduced radiative recombination. Above 1.68 GPa, fluorescence vanishes entirely, attributed to the complete phase transformation from ES-II to ES-III in which radiative recombination becomes non-existent. Notably, owing to stronger quantum confinement effects, CsPbBr3 QDs exhibit an impressive bandgap tuning range of 0.497 eV from 0 to 2.08 GPa, outperforming nanocrystals by 1.4 times and bulk counterparts by 11.3 times. Furthermore, this work analyzes various carrier dynamics processes in the pressure-induced bandgap evolution and electron state transitions, and systematically studies the microphysical mechanisms of optical properties in CsPbBr3 QDs under pressure, offering insights for optimizing optical properties and designing novel materials.
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PURPOSE: Treatment algorithms may consider many factors like glenoid and humeral bone loss, or scores such as the instability severity index score (ISIS). As most studies only evaluate a part of these factors, there is still no evidence-based consensus estalished. Our study aims to summarize the surgical options for treatment of glenoid bone loss (GBL) in anterior shoulder instability. METHODS: Based on the current available literature, surgical options including Bankart repair and glenoid bone augmentation should be considered while taking into consideration the degree of bone loss which has been divided into < 10%, 10-20% and > 20%. RESULTS: There are many new techniques evolving including arthroscopic anatomic glenoid reconstruction with bone blocks. CONCLUSION: Future long-term outcome studies and randomized controlled trials comparing established techniques will be needed for new evidence-based treatment algorithms.
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The stimulus-responsive smart switching of aggregation-induced emission (AIE) features has attracted considerable attention in 4D information encryption, optical sensors and biological imaging. Nevertheless, for some AIE-inactive triphenylamine (TPA) derivatives, activating the fluorescence channel of TPA remains a challenge based on their intrinsic molecular configuration. Here, we took a new design strategy for opening a new fluorescence channel and enhancing AIE efficiency for (E)-1-(((4-(diphenylamino)phenyl)imino)methyl)naphthalen-2-ol. The turn-on methodology employed is based on pressure induction. Combining ultrafast and Raman spectra with high-pressure in situ showed that activating the new fluorescence channel stemmed from restraining intramolecular twist rotation. Twisted intramolecular charge transfer (TICT) and intramolecular vibration were restricted, which induced an increase in AIE efficiency. This approach provides a new strategy for the development of stimulus-responsive smart-switch materials.
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The magnetic properties and electrical transport behaviors of half-metallic ferromagnet chromium dioxide (CrO2) powders under high pressure have been investigated by in situ electrical resistivity, magneto-resistivity, and Hall-effect measurements. Our results reveal that the Hall coefficient, carrier concentration, and mobility all present discontinuous changes from 11.7 GPa to 14.9 GPa which can be attributed to the second-order structural transition from the rutile-type to CaCl2-type. However, the resistivity decreases monotonically from ambient pressure to 16.5 GPa. This is due to, first, the decreased carrier concentration and the increased carrier mobility canceling the effects of each other on the resistivity; second, according to the calculation results, the bandgap of CrO2 decreased gradually with the pressure, and the bandgaps of the rutile-type phase and the CaCl2-type phase are extremely similar. CrO2 exhibits a linear and negative magnetoresistance under the applied magnetic field (0â¼ ± 15 kOe). As the pressure increases, the magnetoresistance remains negative, but it becomes nonlinear and less symmetric, suggesting that pressure has an appreciable impact on the double-exchange mechanism leading to ferromagnetism in CrO2.
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Organic materials exhibit efficient light absorption and low-temperature, large-scale processability, and have stimulated enormous research efforts for next-generation optoelectronics. While, high-performance organic devices with fast speed and high responsivity still face intractable challenges, due to their intrinsic limitations including finite carrier mobility and high exciton binding energy. Here an ultrafast and highly sensitive broadband phototransistor is demonstrated by integrating high-quality pentacene single crystal with monolayer graphene. Encouragingly, the -3 dB bandwidth can reach up to 26 kHz, which is a record-speed for such sensitized organic phototransistors. Enormous absorption, long exciton diffusion length of pentacene crystal, and efficient interfacial charge transfer enable a high responsivity of >105 A W-1 and specific detectivity of >1011 Jones. Moreover, self-powered weak-light detection is realized using a simple asymmetric configuration, and the obvious zero-bias photoresponses can be displayed even under 750 nW cm-2 light intensity. Excellent response speed and photoresponsivity enable high-speed image sensor capability in UV-Vis ranges. The results offer a practical strategy for constructing high-performance self-powered organic hybrid photodetectors, with strong applicability in wireless, weak-light detection, and video-frame-rate imaging applications.
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The oxidation of methane to a high-value-added chemical, methanol, is a major challenge in catalysis, requiring high energy input to overcome the CH3-H bond activation energy barrier. Based on density functional theory (DFT) calculations, methane oxidation to methanol is catalyzed by hetero-diatomic catalysts (CuZn-NG) with different coordination spheres (CSs). Valence band maximum (VBM), atomic charge and d-band center are selected as analysis methods for the pathway selection and activity of catalysis. The VBM plays a vital role in the catalytic pathway selection, CuZn-NG catalyzes the direct conversion of methane into methanol without side reactions. Alarmingly, the most important reaction step, CH3-H bond activation, is a spontaneously exothermic reaction (releasing 0.06 eV) with CuZn-NPAG as the catalyst, in contrast to most other endothermic reactions in the same activation. By analyzing the atomic charge of the Cu center and O atom, the special electronic phenomenon for this important step is summarized as the "bow-release effect". The CS affects the electronic properties of the active center and further affects the methane oxidation activity. This work provides a useful guide to understand the catalytic selectivity and activity of hetero-diatomic catalysts.
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Impedance spectroscopy (IS) is an indispensable method of exploring electrical properties of materials. In this review, we provide an overview on the specific applications of IS measurement in the investigations of various electrical properties of materials under high pressure, including electric conduction in bulk and grain boundary, dielectric properties, ionic conduction, and electrostrictive effect. Related studies are summarized to demonstrate the method of analyzing different electrical transport processes with various designed equivalent circuits of IS and reveal some interesting phenomena of electrical properties of materials under high pressure.
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Increasing aggregation induced emission (AIE) efficiency is of fundamental interest as it directly reflects performance of multitwist-based luminogens in bioimaging and in the photoelectric device field. However, an effective and convenient methodology to increase AIE efficiency significantly remains a challenge. Here, we present a general strategy to increase AIE efficiency of multitwist-based luminogens by pressure, resulting in a 120.1-fold enhancement of the AIE intensity of tris[4-(diethylamino)phenyl]amine (TDAPA) under high pressure compared to that of the traditional method. AIE efficiency of TDAPA increases from 0.5% to 46.1% during compression. Experimental and theoretical investigations reveal that the AIE efficiency enhancement originates from intramolecular vibration and the twisted intramolecular charge transfer are suppressed under high pressure. High AIE efficiency under high pressure provides an important inspiration for improving performance of multitwist-based luminogens in the lighting and biomedical fields.
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Zn1-xMnxAl2O4:0.1 mol% Cr3+ (0.04≤x≤0.16) phosphors with single spinel phase were synthesized by using sol-gel method and the structure, optical and temperature sensing performances were reported herein. The results of X-ray photoelectron spectra indicate that the inversion defects related to octahedral Zn are reduced and the crystal field surrounding Al changes with Mn2+ doping in ZnAl2O4 lattices. Mn2+/Cr3+ co-doped ZnAl2O4 nanophosphors reveal a green emission band assigned to Mn2+ and a series of red emission peaks assigned to Cr3+, respectively. With the concentration of Mn2+ increasing, the intensity of zero phonon line (R line) assigned to Cr3+ increases, reaching the maximum at the optimal Mn2+ concentration of x=0.14. The energy transfer from Mn2+ to Cr3+ is confirmed with the energy transfer efficiency of 83%. The separation between 2E(eg) and 2E(tg) of Cr3+ is enlarged due to Mn2+ dopants giving rise to a change of crystal field. The luminous intensity ratio between two separated emission peaks at 685 nm (R3) and 689 nm (R2) reveals an obvious temperature dependence. The relative sensitivity changes from 3.7 %K-1 to 0.25 %K-1 with the temperature increasing from 80 K to 310 K, which is much larger than that of ZnAl2O4:Cr3+ nanophosphors without Mn2+, indicating its good application prospect in optical thermometry.
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Termometría , Transferencia de Energía , Iones , Temperatura , Difracción de Rayos XRESUMEN
Rubrene single crystals have received a lot of attention for their great potential in electronic and wearable nanoelectronics due to their high carrier mobility and excellent flexibility. While they exhibited remarkable electrical performances, their intrinsic potential as photon detectors has not been fully exploited. Here, we fabricate a sensitive and ultrafast organic phototransistor based on rubrene single crystals. The device covers the ultraviolet to visible range (275-532 nm), and the responsivity and detectivity can reach up to â¼4000 A W-1 and 1011 jones at 532 nm, respectively. Furthermore, the response times are highly gate-tunable down to sub-90 µs, and the cutoff frequency is â¼4 kHz, which is one of the fastest organic material-based phototransistors reported so far. Equally important is that the fabricated device exhibits stable light detection ability even after 8 months, indicating great long-term stability and excellent environmental robustness. The results suggest that the high-quality rubrene single crystal may be a promising material for future flexible optoelectronics with its intrinsic mechanical flexibility.
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Valence Compton profiles (CPs) (electron momentum density projections) of B-doped carbon nano-onions (CNOs) as a function of the boron doping content were obtained by recording electron energy-loss spectra at large scattering angles using a transmission electron microscope, a technique known as electron Compton scattering from solids (ECOSS). The amplitude of the CPs at zero momentum increases with increasing doping content, while the shape of the CPs becomes narrower with increasing doping content. The differences between the profiles of B-doped CNOs and that of pristine CNOs have been clearly observed. These experimental results indicate substantially greater delocalization of the ground-state charge density in B-doped CNOs than in pristine CNOs. The results clearly demonstrate that the ECOSS technique is an efficient and reliable experimental method for studying electron density distributions in solids as a function of the heteroatom doping content.
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Förster resonance energy transfer (FRET) and Auger recombination in quantum dots (QDs)-molecules system are important mechanisms for affecting performance of their optoelectronic and photosynthesis devices. However, exploring an effective strategy to promote FRET and suppress Auger recombination simultaneously remains a daunting challenge. Here, we report that FRET process is promoted and Auger recombination process is suppressed in CdTe/CdS QDs-Rhodamine101 (Rh101) molecules system upon compression. The greatly improved FRET is attributed to the shortened donor-acceptor distance and increased the number of molecules attached to QDs induced by pressure. The reduced Auger recombination is ascribed to the formation of an alloy layer at the core/shell interface. The FRET can occur 70 times faster than Auger recombination under a high pressure of 0.9â GPa. Our findings demonstrate that high pressure is a robust tool to boost FRET and simultaneously suppress Auger recombination, and provides a new route to QDs-molecules applications.
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Objective: Although emerging evidence suggests that both osteoarthritis (OA) and brain atrophy (as assessed by structural neuroimaging markers) are associated with the risk of dementia, little is known about the association between OA and structural neuroimaging markers. This study aimed to examine the association of OA with changes in structural neuroimaging markers among non-demented older people. Methods: We examined the cross-sectional and longitudinal associations between OA and structural neuroimaging markers (hippocampal volume, entorhinal volume, ventricular volume, and volume of gray matter of the whole brain) among non-demented older people. We categorized our participants as those without OA (OA-) and those with OA (OA+). At baseline, we included 1,281 non-demented older adults, including 1,050 without OA and 231 with OA. Results: In the cross-sectional analysis, we did not observe any significant difference in structural neuroimaging markers between the two OA groups. In the longitudinal analysis, we found that compared to participants without OA, those with OA showed a steeper decline in volumes of the gray matter of the whole brain among non-demented older adults. Conclusions: OA was associated with a steeper decline in volumes of the gray matter of the whole brain over time among non-demented older people.
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Tungsten oxide (WO3) is a wide band gap semiconductor with unintentionally n-doping performance, excellent conductivity, and high electron hall mobility, which is considered as a candidate material for application in optoelectronics. Several reviews on WO3 and its derivatives for various applications dealing with electrochemical, photoelectrochemical, hybrid photocatalysts, electrochemical energy storage, and gas sensors have appeared recently. Moreover, the nanostructured transition metal oxides have attracted considerable attention in the past decade because of their unique chemical, photochromic, and physical properties leading to numerous other potential applications. Owing to their distinctive photoluminescence (PL), electrochromic and electrical properties, WO3 nanostructure-based optical and electronic devices application have attracted a wide range of research interests. This review mainly focuses on the up-to-date progress in different advanced strategies from fundamental analysis to improve WO3 optoelectric, electrochromic, and photochromic properties in the development of tungsten oxide-based advanced devices for optical and electronic applications including photodetectors, light-emitting diodes (LED), PL properties, electrical properties, and optical information storage. This review on the prior findings of WO3-related optical and electrical devices, as well as concluding remarks and forecasts will help researchers to advance the field of optoelectric applications of nanostructured transition metal oxides.
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Nanostructured n-type metal oxides/p-type boron-doped diamond heterojunctions have demonstrated a typical rectification feature and/or negative differential resistance (NDR) potentially applied in wide fields. Recently, the fabrication and electronic transport behavior of n-WO3nanorods/p-diamond heterojunction at high temperatures were studied by Wanget al(2017Appl. Phys. Lett.110052106), which opened the door for optoelectronic applications that can operate at high-temperatures, high-power, and in various harsh environments. In this perspective, an overview was presented on the future directions, challenges and opportunities for the optoelectronic applications based on the n-WO3nanostructures/p-diamond heterojunction. We focus, in particular, on the prospects for its high temperature NDR, UV photodetector, field emission emitters, photocatalyst and optical information storage for a wide range of new optoelectronic applications.
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Lanthanide materials have great applications in optical communication, biological fluorescence imaging, laser, and so on, due to their narrow emission bandwidths, large Stokes' shifts, long emission lifetimes, and excellent photo-stability. However, the photon absorption cross-section of lanthanide ions is generally small, and the luminescence efficiency is relatively low. The effective improvement of the lanthanide-doped materials has been a challenge in the implementation of many applications. The local surface plasmon resonance (LSPR) effect of plasmonic nanoparticles (NPs) can improve the luminescence in different aspects: excitation enhancement induced by enhanced local field, emission enhancement induced by increased radiative decay, and quenching induced by increased non-radiative decay. In addition, plasmonic NPs can also regulate the energy transfer between two close lanthanide ions. In this review, the properties of the nanocomposite systems of lanthanide material and plasmonic NPs are presented, respectively. The mechanism of lanthanide materials regulated by plasmonic NPs and the scientific and technological discoveries of the luminescence technology are elaborated. Due to the large gap between the reported enhancement and the theoretical enhancement, some new strategies applied in lanthanide materials and related development in the plasmonic enhancing luminescence are presented.