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Photocatalytic overall splitting of pure water (H2O) without sacrificial reagent to hydrogen (H2) and oxygen (O2) holds a great potential for achieving carbon neutrality. Herein, by anchoring cobalt sulfide (Co9S8) as cocatalyst and cadmium sulfide (CdS) as light absorber to channel wall of a porous polymer microreactor (PP12), continuous violent H2 and O2 bubbling productions from photocatalytic overall splitting of pure H2O without sacrificial reagent is achieved, with H2 and O2 production rates as high as 4.41 and 2.20 mmol h-1 gcat.-1 respectively. These are significantly enhanced than those in the widely used stirred tank-type reactor in which no O2 is produced and H2 production rate is only 0.004 mmol h-1 gcat.-1. Besides improved charge separation and interaction of H2O with photocatalyst in PP12, bonding interaction of Co9S8 with PP12 creates abundant catalytic active sites for simultaneous productions of H2 and O2, thus leading to the significantly enhanced H2 and O2 bubbling productions in PP12. This offers a new strategy to enhance photocatalytic overall splitting of pure H2O without sacrificial reagent.
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Solar-energy-driven photoreduction of CO2 is promising in alleviating environment burden, but suffers from low efficiency and over-reliance on sacrificial agents. Herein, rhenium (Re) is atomically dispersed in In2O3 to fabricate a 2Re-In2O3 photocatalyst. In sacrificial-agent-free photoreduction of CO2 with H2O, 2Re-In2O3 shows a long-term stable efficiency which is enhanced by 3.5 times than that of pure In2O3 and is also higher than those on Au-In2O3, Ag-In2O3, Cu-In2O3, Ir-In2O3, Ru-In2O3, Rh-In2O3 and Pt-In2O3 photocatalysts. Moreover, carbon-based product of the photoreduction overturns from CO on pure In2O3 to CH3OH on 2Re-In2O3. Re promotes charge separation, H2O dissociation and CO2 activation, thus enhancing photoreduction efficiency of CO2 on 2Re-In2O3. During the photoreduction, CO is a key intermediate. CO prefers to desorption rather than hydrogenation on pure In2O3, as CO binds to pure In2O3 very weakly. Re strengthens the interaction of CO with 2Re-In2O3 by 5.0 times, thus limiting CO desorption but enhancing CO hydrogenation to CH3OH. This could be the origin for photoreduction product overturn from CO on pure In2O3 to CH3OH on 2Re-In2O3. The present work opens a new way to boost sacrificial-agent-free photoreduction of CO2.
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BACKGROUND: A previously trained deep learning-based smartphone app provides an artificial intelligence solution to help diagnose biliary atresia from sonographic gallbladder images, but it might be impractical to launch it in real clinical settings. This study aimed to redevelop a new model using original sonographic images and their derived smartphone photos and then test the new model's performance in assisting radiologists with different experiences to detect biliary atresia in real-world mimic settings. METHODS: A new model was first trained retrospectively using 3659 original sonographic gallbladder images and their derived 51,226 smartphone photos and tested on 11,410 external validation smartphone photos. Afterward, the new model was tested in 333 prospectively collected sonographic gallbladder videos from 207 infants by 14 inexperienced radiologists (9 juniors and 5 seniors) and 4 experienced pediatric radiologists in real-world mimic settings. Diagnostic performance was expressed as the area under the receiver operating characteristic curve (AUC). RESULTS: The new model outperformed the previously published model in diagnosing BA on the external validation set (AUC 0.924 vs 0.908, P = 0.004) with higher consistency (kappa value 0.708 vs 0.609). When tested in real-world mimic settings using 333 sonographic gallbladder videos, the new model performed comparable to experienced pediatric radiologists (average AUC 0.860 vs 0.876) and outperformed junior radiologists (average AUC 0.838 vs 0.773) and senior radiologists (average AUC 0.829 vs 0.749). Furthermore, the new model could aid both junior and senior radiologists to improve their diagnostic performances, with the average AUC increasing from 0.773 to 0.835 for junior radiologists and from 0.749 to 0.805 for senior radiologists. CONCLUSIONS: The interpretable app-based model showed robust and satisfactory performance in diagnosing biliary atresia, and it could aid radiologists with limited experiences to improve their diagnostic performances in real-world mimic settings.
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Atresia Biliar , Aplicaciones Móviles , Lactante , Niño , Humanos , Vesícula Biliar/diagnóstico por imagen , Inteligencia Artificial , Atresia Biliar/diagnóstico por imagen , Estudios Retrospectivos , RadiólogosRESUMEN
CO2 methanation has attracted considerable attention as a promising strategy for recycling CO2 and generating valuable methane. This study presents a niobium-doped CeO2-supported Ni catalyst (Ni/NbCe), which demonstrates remarkable performance in terms of CO2 conversion and CH4 selectivity, even when operating at a low temperature of 250 °C. Structural analysis reveals the incorporation of Nb species into the CeO2 lattice, resulting in the formation of a Nb-Ce-O solid solution. Compared with the Ni/CeO2 catalyst, this solid solution demonstrates an improved spatial distribution. To comprehend the impact of the Nb-Ce-O solid solution on refining the electronic properties of the Ni-Ce interfacial sites, facilitating H2 activation, and accelerating the hydrogenation of CO2* into HCOO*, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis and density functional theory (DFT) calculations were conducted. These investigations shed light on the mechanism through which the activity of CO2 methanation is enhanced, which differs from the commonly observed CO* pathway triggered by oxygen vacancies (OV). Consequently, this study provides a comprehensive understanding of the intricate interplay between the electronic properties of the catalyst's active sites and the reaction pathway in CO2 methanation over Ni-based catalysts.
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By supporting platinum (Pt) and cadmium sulfide (CdS) nanoparticles on indium oxide (In2 O3 ), we fabricated a CdS/Pt/In2 O3 photocatalyst. Selective photoreduction of carbon dioxide (CO2 ) to methane (CH4 ) was achieved on CdS/Pt/In2 O3 with electronic Pt-In2 O3 interactions, with CH4 selectivity reaching to 100 %, which is higher than that on CdS/Pt/In2 O3 without electronic Pt-In2 O3 interactions (71.7 %). Moreover, the enhancement effect of electronic Pt-(metal-oxide) interactions on selective photoreduction of CO2 to CH4 also occurs by using other common metal oxides, such as photocatalyst supports, including titanium oxide, gallium oxide, zinc oxide, and tungsten oxide. The electronic Pt-(metal-oxide) interactions separate photogenerated electron-hole pairs and convert CO2 into CO2 δ- , which can be easily hydrogenated into CH4 via a CO2 δ- âHCOO*âHCO*âCH*âCH4 path, thus boosting selective photoreduction of CO2 to CH4 . This offers a new way to achieve selective photoreduction of CO2 .
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Photocatalytic hydrogen (H2 ) production is significant to overcome challenges like fossil fuel depletion and carbon dioxide emission, but its efficiency is still far below that which is needed for commercialization. Herein, we achieve long-term stable H2 bubbling production from water (H2 O) and lactic acid via visible-light-driven photocatalysis in a porous microreactor (PP12); the catalytic system benefits from photocatalyst dispersion, charge separation, mass transfer, and dissociation of O-H bonds associated with H2 O. With the widely used platinum/cadmium-sulfide (Pt/CdS) photocatalyst, PP12 leads to a H2 bubbling production rate of 602.5â mmol h-1 m-2 , which is 1000â times higher than that in a traditional reactor. Even when amplifying PP12 into a flat-plate reactor with an area as large as 1â m2 and extending the reaction time to 100â h, the H2 bubbling production rate still remains at around 600.0â mmol h-1 m-2 , offering great potential for commercialization.
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Objective: To evaluate the diagnostic performance and inter-observer agreement of the American College of Radiology Ovarian-Adnexal Reporting and Data System Ultrasound (O-RADS) in the diagnosis of ovarian masses in children. Methods: From June 2012 to December 2021, 163 ovarian masses in 159 patients with pathologic results were retrospectively analyzed. Each mass was classified into an O-RADS category according to the criteria. The diagnostic performance of O-RADS for detecting malignant ovarian masses was assessed using histopathology as the reference standard. Kappa (k) statistic was used to assess inter-observer agreement between a less-experienced and a well-experienced radiologist. Results: Out of 163 ovarian masses, 18 (11.0%) were malignant and 145 (89.0%) were benign. The malignancy rates of O-RADS 5, O-RADS 4, and O-RADS 3 masses were 72.7%, 34.6%, and 4.8%, respectively. The area under the receiver operating characteristic curve was 0.944 (95% CI, 0.908-0.981). The optimal cutoff value for predicting malignant ovarian masses was > O-RADS 3 with a sensitivity, specificity, and accuracy of 94.4%, 86.2% and 86.2% respectively. The inter-observer agreement of the O-RADS category was good (k = 0.777). Conclusions: O-RADS has a high diagnostic performance for children with ovarian masses. It provides an effective malignant risk classification for ovarian masses in children, which shows high consistency between radiologists with different levels of experience.
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The absorption coefficient of fused silica for a mid-infrared (IR) laser is higher than that for a near-IR laser, but smaller than that for a far-IR laser. Therefore, the energy coupling efficiency of the mid-IR laser is higher than that for the near-IR laser, while the penetration depth is higher than that for the far-IR laser. Thus, the mid-IR laser is highly efficient in mitigating damage growth. In this study, a deuterium fluoride (DF) laser with a center wavelength of 3.8 µm was used to interact with fused silica. The temperature variation, changes in the reflected and transmitted intensities of the probe light incident on the laser irradiation area, and the vaporization and melting sputtering process were analyzed. The results demonstrate that when the laser intensity was low (<1.2 kW/cm2), no significant melting was observed, and the reflection and transmission properties gradually recovered after the end of the laser irradiation process. With a further increase in the laser intensity, the sample gradually melted and vaporized. At a laser intensity above 5.1 kW/cm2, the temperature of the sample increased rapidly and vapors in huge quantity evaporated from the surface of the sample. Moreover, when the laser intensity was increased to 9.5 kW/cm2, the sample melted and an intense melting sputtering process was observed, and the sample was melted through.
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Electrocatalytic glucose oxidation reaction (GOR) is the key to construct sophisticated devices for fast and accurately detecting trace glucose in blood and food. Herein, a noble-metal-free Cu/C-60 catalyst is fabricated by supporting Cu2O-CuO nanoparticles on carbon nanotubes through a novel discharge process. For GOR, Cu/C-60 shows a sensitivity as high as 532 µA mM-1 cm-2, a detection limit as low as 1 µM and a steady-state response time of only 5.5 s. Moreover, Cu/C-60 has outstanding stability and anti-interference ability to impurities. The synergistic effect of Cu2O-CuO could improve the adsorption and conversion of glucose, thus enhancing GOR performance. By using Cu/C-60, we fabricate a three-electrode chip. A portable and compact electrochemical system is constructed by connecting the three-electrode chip with Cu/C-60 to an integrated circuit board and a mobile phone for recording and displaying data. The portable and compact electrochemical system results in a GOR sensitivity of 501 µA mM-1 cm-2, which is close to the data measured on the bloated electrochemical workstation. The detection limit of the portable and compact electrochemical system in GOR is 50 µM. This is higher than those obtained on the bloated electrochemical workstation, but is much lower than the common blood glucose concentration of human body (>3 mM). This demonstrates the accuracy, reasonability and applicability of the portable and compact electrochemical system. The results of the present work are helpful for fabricating fast, efficient and portable devices for detecting trace amount of glucose in blood and food.
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Lead ion (Pb2+) is one of the most common water pollutants. Herein, with bamboo as the raw material, we fabricate a thin-walled hollow ellipsoidal carbon-based adsorbent (CPCs900) containing abundant O-containing groups and carbon defects and having a specific surface area as large as 730.87 m2 g-1. CPCs900 shows a capacity of 37.26 mg g-1 for adsorbing Pb2+ in water and an efficiency of 98.13% for removing Pb2+ from water. This is much better than the activated carbon commonly used for removing Pb2+ from water (12.19 mg g-1, 30.48%). The bond interaction of Pb2+ with the O-containing groups on CPCs900 and the electrostatic interaction of Pb2+ with the electron-rich carbon defects on CPCs900 could be the main forces to drive Pb2+ adsorption on CPCs900. The outstanding adsorption performance of CPCs900 could be due to the abundant O-containing groups and carbon defects as well as the large specific surface area of CPCs900. Bamboo has a large reserve and a low price. The present work successfully converts bamboo into adsorbents with outstanding performances in removing Pb2+ from water. This is of great significance for meeting the huge industrial demand on highly efficient adsorbents for removing toxic metal ions from water.
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Contaminantes Químicos del Agua , Contaminantes del Agua , Adsorción , Carbón Orgánico/química , Concentración de Iones de Hidrógeno , Iones , Cinética , Plomo , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
Photocatalytic hydrogen peroxide (H2O2) production will become a burgeoning strategy for solar energy utilization by selective oxygen reduction reaction (ORR). Polymeric carbon nitride (PCN) shows relatively high two-electron ORR selectivity for H2O2 production but still limited low H2O2 production efficiency due to slow exciton dissociation. Herein, we constructed a heptazine/triazine layer stacked carbon nitride heterojunction with fluorine/potassium (F/K) dual sites (FKHTCN). The introduction of F/K not only can regulate layer components to enhance the charge separation efficiency but, more importantly, also optimize the adsorption of surface oxygen molecules and intermediate *OOH during H2O2 production. Consequently, FKHTCN efficiently improves the photocatalytic H2O2 production rate up to 3380.9 µmol h-1 g-1, nearly 15 times higher than that of traditional PCN. Moreover, a production-utilization cascade system was designed to explore their practical application in environmental remediation. This work lays out the importance of engineering a layer-stacked configuration and active sites for enhancing photocatalysis.
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Variations in the visceral vasculature are often encountered, but rarely cause clinical symptoms. We report a 12-year-old girl with portal hypertension caused by congenital variations in visceral vessels. The clinical manifestations included gastrointestinal hemorrhage and ascites. The common hepatic artery and splenic artery stem shared the same trunk from the aorta, and the common hepatic artery was directly connected with the main portal vein to form an arteriovenous fistula. In addition, the left hepatic artery and the left gastric artery shared a common trunk termed the "hepatic-gastric trunk" which originated from the anterior wall of the aorta, while the right hepatic artery originated from the superior mesenteric artery and supplied the right liver. The patient was treated with interventional embolization and remained in good condition throughout the follow-up and at the time of publication.
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Photoelectrochemical catalysis is an attractive way to provide direct hydrogen production from solar energy. However, solar conversion efficiencies are hindered by the fact that light harvesting has so far been of limited efficiency in the near-infrared region as compared to that in the visible and ultraviolet regions. Here we introduce near-infrared-active photoanodes that feature lattice-matched morphological hetero-nanostructures, a strategy that improves energy conversion efficiency by increasing light-harvesting spectral range and charge separation efficiency simultaneously. Specifically, we demonstrate a near-infrared-active morphological heterojunction comprised of BiSeTe ternary alloy nanotubes and ultrathin nanosheets. The heterojunction's hierarchical nanostructure separates charges at the lattice-matched interface of the two morphological components, preventing further carrier recombination. As a result, the photoanodes achieve an incident photon-to-current conversion efficiency of 36% at 800 nm in an electrolyte solution containing hole scavengers without a co-catalyst.
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The electrocatalytic oxygen evolution reaction from H2O (OER) is essential in a number of areas like electrocatalytic hydrogen production from H2O. A Ni oxyhydroxide nanosheet (NiNS) is among the most widely studied OER catalysts but still suffers from low activity, sluggish kinetics, and poor stability. Herein, we incorporate MoO3 patches into NiNS to form a nanosheet with an intimate Ni-Mo interface (NiMoNS) for the OER. The overpotential at 10 mA cm-2 and Tafel slope on NiMoNS (260 mV, 54.7 mV dec-1) are lower than those on NiNS (296 mV, 89.3 mV dec-1), implying that higher activity and faster kinetics are achieved on NiMoNS. There is no change in electrocatalytic efficiency of NiMoNS after 18 h of OER, but the electrocatalytic efficiency of NiNS decreases by 56% after only 8 h of OER. Thus, NiMoNS has better stability. The intimate Ni-Mo interface promotes two-dimensional lateral growth of NiMoNS to form a surface area 1.5 times larger than that of NiNS, and facilitates electron transfer from Ni to Mo. This makes the Ni3+/Ni2+ ratio on the NiMoNS surface (1.32) higher than that on the NiNS surface (0.68). Moreover, the Ni3+/Ni2+ ratio on NiMoNS surface increases to 1.81 after 18 h of OER but the Ni3+/Ni2+ ratio on the NiNS surface decreases to 0.51 after 8 h of OER. Therefore, the NiMoNS surface has more abundant and stable Ni3+ sites which are catalytically active toward OER. This could be the reason for the enhanced activity, kinetics, and stability of NiMoNS. The results are very valuable for fabricating more efficient catalysts for electrocatalysis.
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Electrocatalytic oxidation of water (i.e., oxygen evolution reaction, OER) plays crucial roles in energy, environment, and biomedicine. It is a key factor affecting the efficiencies of electrocatalytic reactions conducted in aqueous solution, e.g., electrocatalytic water splitting and glucose oxidation reaction (GOR). However, electrocatalytic OER still suffers from problems like high overpotential, sluggish kinetics, and over-reliance on expensive noble-metal-based catalysts. Herein, 15 nm thick carbon-based shell coated tungsten oxide (CTO) nanospheres are loaded on nickel foam to form CTO/NF. An enhanced electrocatalytic OER is triggered on CTO/NF, with the overpotential at 50 mA cm-2 (317 mV) and the Tafel slope (70 mV dec-1) on CTO/NF lower than those on pure tungsten oxide (360 mV, 117 mV dec-1) and noble-metal-based IrO2 catalysts (328 mV, 96 mV dec-1). A promoted electrocatalytic GOR is also achieved on CTO/NF, with efficiency as high as 189 µA mM-1 cm-2. The carbon-based shell on CTO is flexible for electron transfer between catalyst and reactants and provides catalytically active sites. This improves reactant adsorption and O-H bond dissociation on the catalyst, which are key steps in OER and GOR. The carbon-based shell on CTO retains the catalyst as nanospheres with a higher surface area, which facilitates OER and GOR. It is the multiple roles of the carbon-based shell that increases the electrocatalytic efficiency. These results are helpful for fabricating more efficient noble-metal-free electrocatalysts.
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COMSOL Multiphysics was employed to establish a dislocation model based on the Alexander and Haasen (AH) model, the heat conduction equation, and Hooke's law for calculating the dislocation distribution of germanium (Ge) under laser irradiation. The numerical simulation results were obtained. A continuous 1080 nm laser was utilized to ablate the monocrystalline Ge wafers to validate the model. The experimental results show that no surface damage appears until the irradiances go up to 234W/cm2 for 100 ms laser ablation. This is consistent with the numerical findings. The initiation times of surface damage by the experiments at 234W/cm2 and above agree well with the numerical results, which means that the model can efficiently predict the dislocation field.
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Graphene oxide (GO) nanosheets are promising noble-metal-free catalysts. However, the catalytic activity and selectivity of GO are still very low. Herein, GO is first functionalized via noncovalent interactions by an aspartic acid modified anhydride having COOH groups to form A-GO. A-GO is more conductive and hydrophilic than GO and P-GO synthesized via functionalizing GO by a COOH-free anhydride. Then, we load CdS nanoparticles, which are responsible for absorbing light to produce charge carriers, on A-GO to fabricate a CdS/A-GO photocatalyst without noble metals for the photoreduction of CO2 by H2O. CdS/A-GO exhibits a higher photoreduction efficiency than that of CdS/GO and CdS/P-GO. The main carbon-based photoreduction product of CdS/A-GO is CH3OH, whereas that of CdS/GO and CdS/P-GO is CO. The more conductive and hydrophilic A-GO triggers a more efficient electron transfer, CO2 adsorption, and production of hydrogen atoms from H2O dissociation, thus leading to the higher photoreduction efficiency and product change on CdS/A-GO. Besides, the COOH groups of the aspartic acid modified anhydride supply their hydrogen atoms to promote the conversion from CO2 to CH3OH on CdS/A-GO. Therefore, noncovalently functionalizing GO with different active species can efficiently improve the catalytic performance of GO. This opens a new way to design and construct noble-metal-free catalysts with enhanced activity and selectivity.
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The low efficiency of photodynamic therapy (PDT) is caused by tumor hypoxia and the adaptive immune resistance/evasion of tumor cells, while the currently emerging immune checkpoint therapy restores the intrinsic immune capacities but can't directly attack the tumor cells. Methods: Herein we report an integrated nanoplatform that combines PDT with immunotherapy to enhance photodynamic therapeutic effects and simultaneously inhibit tumor cells resistance/evasion. To achieve this, we fabricated Mn@CaCO3/ICG nanoparticles and loaded them with PD-L1-targeting siRNA. Results: Thanks to the protection of CaCO3 on the loaded ICG and the oxygen produced by MnO2, an enhanced photodynamic therapeutic effect in vitro was observed. In vivo experiments demonstrated that the nanoplatform could efficiently deliver the loaded drug to the tumor tissues and significantly improve tumor hypoxia, which further contributes to the therapeutic effect of PDT in vivo. Moreover, the synergistic benefits derived from the siRNA, which silenced the checkpoint gene PD-L1 that mediates the immune resistance/evasion, resulted in a surprising therapeutic effect to rouse the immune system. Conclusions: The combination treatment strategy has great potential to be developed as a new and robust method for enhanced PDT therapy with high efficiency and a powerful antitumor immune response based on PD-L1 blockade.
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Antígeno B7-H1/genética , Carbonato de Calcio/química , Sistemas de Liberación de Medicamentos/métodos , Compuestos de Manganeso/química , Neoplasias/tratamiento farmacológico , Óxidos/química , Fotoquimioterapia/métodos , Microambiente Tumoral/genética , Animales , Antígeno B7-H1/inmunología , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos/instrumentación , Femenino , Humanos , Inmunoterapia , Masculino , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Nanopartículas/administración & dosificación , Nanopartículas/química , Neoplasias/genética , Neoplasias/inmunología , Fotoquimioterapia/instrumentación , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/química , ARN Interferente Pequeño/genética , Microambiente Tumoral/inmunologíaRESUMEN
Three-dimensional and time-dependent thermal lens distribution was measured in K9 glass by a Mach-Zehnder interferometer in this paper. The thermal lens was introduced by focusing a millisecond pulse laser into the glass, and the phase information was extracted by Fourier analysis. The specific internal three-dimensional refractive index variation (RIV) was then deduced from phase maps by an inverse Abel algorithm. It is demonstrated that the stress-induced birefringence would lead to negative RIV, which is contrary to results of temperature increment. The method proposed herein would provide a novel idea for measurement of thermal lenses.
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Emerging Fenton-like activity of copper ions has inspired great exploration for tumor microenvironment-activated tumor therapy due to the toxic ·OH production for chemodynamic therapy and extra oxygen generation for photodynamic therapy (PDT). Still, the ·OH produced by copper ions is not satisfied even when copper ions are placed in a low pH environment (pH ≈ 5.0). To amplify its Fenton-like activity, in this work, one kind of Cu2+ -protein self-assemblies (C-m-ABs) loaded with photosensitizer indocyanine green (ICG) is constructed, which can catalyze H2 O2 generating more amounts of ·OH under light irradiation once Cu2+ is reduced to Cu+ by glutathione. Such fantastic phenomena confirms that C-m-ABs can act as a photo-Fenton-like agent. Furthermore, C-m-ABs can dramatically accelerate O2 generation (catalase activity) to enhance the PDT of ICG. After loading with the anticancer drug doxorubicin, C-m-ABs are further self-assembled into novel nanobelts, which simultaneously exhibit superior photo-heat conversion effects, enhanced r1 relaxation (21.416 s-1 mm-1 ) and stimuli-responsive drug release behaviors. High cytotoxicity in vitro, effective tumor accumulation capacity observed by fluorescence/photoacoustic/magnetic resonance imaging, and enhanced chemo-/photodynamic/photothermal therapeutic performance are achieved. Based on these results, a photo-Fenton-like metal-protein self-assemblies demonstrate great potential for tumor theranostics.