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BACKGROUND: Immune-related characteristics can serve as reliable prognostic biomarkers in various cancers. Herein, we aimed to construct an individualized immune prognostic signature in nasopharyngeal carcinoma (NPC). METHODS: This study retrospectively included 455 NPC samples and 39 normal healthy nasopharyngeal tissue specimens. Samples from Gene Expression Omnibus (GEO) were obtained as discovery cohort to screen candidate prognostic immune-related gene pairs based on relative expression ordering of the genes. Quantitative real-time reverse transcription-PCR was used to detect the selected genes to construct an immune-related gene pair signature in training cohort, which comprised 118 clinical samples, and was then validated in validation cohort 1, comprising 92 clinical samples, and validation cohort 2, comprising 88 samples from GEO. RESULTS: We identified 26 immune-related gene pairs as prognostic candidates in discovery cohort. A prognostic immune signature comprising 11 immune gene pairs was constructed in training cohort. In validation cohort 1, the immune signature could significantly distinguish patients with high or low risk in terms of progression-free survival (PFS) (hazard ratio [HR] 2.66, 95 % confidence interval (CI) 1.17-6.02, P=0.015) and could serve as an independent prognostic factor for PFS in multivariate analysis (HR 2.66, 95 % CI 1.17-6.02, P=0.019). Similar results were obtained using validation cohort 2, in which PFS was significantly worse in high risk group than in low risk group (HR 3.02, 95 % CI 1.12-8.18, P=0.022). CONCLUSIONS: The constructed immune signature showed promise for estimating prognosis in NPC. It has potential for translation into clinical practice after prospective validation.
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Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/imunologia , Carcinoma Nasofaríngeo/mortalidade , Masculino , Feminino , Prognóstico , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/patologia , Estudos Retrospectivos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Adulto , Idoso , Regulação Neoplásica da Expressão GênicaRESUMO
Background: Labeled antibodies are excellent imaging agents in oncology to non-invasively visualize cancer-related antigens expression levels. However, tumor tracer uptake (TTU) of specific antibodies in-vivo may be inferior to non-specific IgG in some cases. Objectives: To explore factors affecting labeled antibody visualization by PD-L1 specific and non-specific imaging of nude mouse tumors. Methods: TTU was observed in RKO model on Cerenkov luminescence (CL) and near-infrared fluorescence (NIRF) imaging of radionuclide 131I or NIRF dyes labeled Atezolizumab and IgG. A mixture of NIRF dyes labeled Atezolizumab and 131I-labeled IgG was injected, and TTU was observed in the RKO and HCT8 model by NIRF/CL dual-modality in-situ imaging. TTU were observed by 131I-labeled Atezolizumab and IgG in-vitro distribution. Results: Labeled IgG concentrated more in tumors than Atezolizumab. NIRF/CL imaging in 24 to 168 h showed that TTU gradually decreased over time, which decreased more slowly on CL imaging compared to NIRF imaging. The distribution data in-vitro showed that TTU of 131I-labeled IgG was higher than that of 131I-labeled Atezolizumab at any time point. Conclusion: Non-specific IgG may not be suitable as a control for Atezolizumab in comparing tumor PD-L1 expression in nude mice via labeled antibody optical imaging under certain circumstances.
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Antígeno B7-H1 , Camundongos Nus , Animais , Antígeno B7-H1/metabolismo , Humanos , Camundongos , Linhagem Celular Tumoral , Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais Humanizados/farmacocinética , Imagem Óptica/métodos , Radioisótopos do Iodo/química , Neoplasias/diagnóstico por imagem , Imunoglobulina G/química , Imunoglobulina G/metabolismo , Feminino , LuminescênciaRESUMO
Abiotic stress caused by soil salinization remains a major global challenge that threatens and severely impacts crop growth, causing yield reduction worldwide. In this study, we aim to investigate the damage of salt stress on the leaf physiology of two varieties of rice (Huanghuazhan, HHZ, and Xiangliangyou900, XLY900) and the regulatory mechanism of Hemin to maintain seedling growth under the imposed stress. Rice leaves were sprayed with 5.0 µmol·L-1 Hemin or 25.0 µmol·L-1 ZnPP (Zinc protoporphyrin IX) at the three leaf and one heart stage, followed by an imposed salt stress treatment regime (50.0 mmol·L-1 sodium chloride (NaCl)). The findings revealed that NaCl stress increased antioxidant enzymes activities and decreased the content of nonenzymatic antioxidants such as ascorbate (AsA) and glutathione (GSH). Furthermore, the content of osmoregulatory substances like soluble proteins and proline was raised. Moreover, salt stress increased reactive oxygen species (ROS) content in the leaves of the two varieties. However, spraying with Hemin increased the activities of antioxidants such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) and accelerated AsA-GSH cycling to remove excess ROS. In summary, Hemin reduced the effect of salt stress on the physiological characteristics of rice leaves due to improved antioxidant defense mechanisms that impeded lipid peroxidation. Thus, Hemin was demonstrated to lessen the damage caused by salt stress.
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Antioxidantes , Glutationa , Hemina , Oryza , Estresse Salino , Oryza/efeitos dos fármacos , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Hemina/farmacologia , Antioxidantes/metabolismo , Estresse Salino/efeitos dos fármacos , Glutationa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Ascórbico/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Cloreto de Sódio/farmacologia , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismoRESUMO
Native starch has poor stability and usually requires modification to expand its industrial application range. Commonly used methods are physical, chemical, enzymatic and compound modification. Microwave radiation, as a kind of physical method, is promising due to its uniform energy radiation, greenness, safety, non-toxicity. It can meet the demand of consumers for safe food. Microwave-assisted modification with other methods can directly or indirectly affect the structure of starch granules to obtain modified starch with high degree of substitution and low viscosity, and the modification efficiency is greatly improved. This paper reviews the effect of microwave radiation on the physicochemical properties of starch, such as granule morphology, crystallization characteristics, and gelatinization characteristics, as well as the application of microwave radiation in starch modification and starch food processing. It provides theoretical references and suggestions for the research of microwave heating modified starch and the deep processing of starchy foods.
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Micro-Ondas , Amido , Amido/química , Viscosidade , Cristalização , Manipulação de AlimentosRESUMO
Recently, various transition metal dichalcogenides (TMDs)/Ga2O3 heterostructures have emerged as excellent candidates for the development of broadband photodetection, exhibiting various merits such as broadband optical absorption, efficient interlayer carrier transfer, a relatively simple fabrication process, and potential for flexibility. In this work, vertically stacked MoSe2/Ga2O3, WS2/Ga2O3, and WSe2/Ga2O3 heterostructures were experimentally synthesized, all exhibiting broadband light absorption, spanning at least from 200 to 800 nm. The absorption coefficients of these TMDs/Ga2O3 heterostructures are significantly improved compared to those of individual Ga2O3 films. The superior performance can be attributed to the type-I band alignment and efficient interlayer carrier transfer, which result from various band offsets along with the different doping conditions of the TMD layers, leading to distinct photoluminescence (PL) emission properties. Through a detailed analysis of the excitation-power-dependent PL spectra, we offer an in-depth discussion of the interlayer carrier transfer mechanism in the TMDs/Ga2O3 heterostructures. Regarding interlayer coupling effects, the shift of the EF of TMD layers plays a crucial role in modulating their trion emission properties. These findings suggest that these three TMDs/Ga2O3 heterostructures have great potential in broadband photodetection, and our in-depth physical mechanism analysis lays a solid foundation for a new device design.
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BACKGROUND: This study aimed to investigate the clinical benefit of adding concurrent chemotherapy to intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC) patients with an intermediate risk (stage II and T3N0M0). METHODS: A multicenter phase II randomized trial was conducted in intermediate-risk NPC patients. Enrolled patients were previously untreated and aged ranged from 18 to 70 years without severe coexisting diseases. Patients were randomly assigned to receive IMRT alone or IMRT+concurrent chemotherapy (CC; three cycles of 80â¯mg/m2 cisplatin every 3 weeks). Primary endpoint was defined as 3year progression-free survival (PFS). The secondary endpoints were distant metastasis-free survival (DMFS), locoregional relapse-free survival (LRRFS), overall survival (OS), and treatment-associated toxicity. We registered this study with Chinese Clinical Trial Registry (CliCTR1800017132; registered July 13, 2018, study start July 13, 2018). RESULTS: From November 2015 to July 2019, 42 patients with stage II and T3N0M0 NPC were enrolled; 20 patients received IMRT alone while 22 patients received IMRT+CC. After a median of 58 months of follow-up, we estimated the 3year PFS rates as 90% (IMRT group) and 86.4% (IMRT+CC group; hazard ratio 1.387, 95% confidence interval 0.240-8.014; Pâ¯= 0.719). The 3year PFS, OS, and cumulative DMFS and LRRFS showed no significant differences between the two groups (Pâ¯> 0.05). However, the IMRT group displayed a lower incidence of nausea/vomiting, leucopenia, and dry mouth than the IMRT+CC group. CONCLUSION: Adding CC to IMRT provided no survival benefit but increased treatment-associated toxicities in patients with intermediate-risk NPC.
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Importance: Induction chemotherapy plus concurrent chemoradiotherapy is recommended for locoregionally advanced nasopharyngeal carcinoma but is associated with higher rates of acute toxic effects and low compliance. Evidence on de-escalating treatment intensity after induction chemotherapy is limited. Objective: To assess if radiotherapy was noninferior to chemoradiotherapy after induction chemotherapy for locoregionally advanced nasopharyngeal carcinoma. Design, Setting, and Participants: From April 2015 to March 2018, a multicenter, open-label, randomized, noninferiority, phase 3 trial was conducted at 5 Chinese hospitals. A total of 383 patients aged 18 to 70 years with an untreated histologically confirmed nonkeratinizing tumor, Karnofsky performance status score not worse than 70, proper organ function, and stage III to IVB nasopharyngeal cancer were enrolled. Data were analyzed from April 2023 to June 2023. Interventions: Patients were assigned randomly. Both groups received 3 cycles of induction chemotherapy consisting of intravenous administration (on day 1) of cisplatin at 60 mg/m2 and docetaxel at 60 mg/m2 and continuous intravenous infusion (from day 1 to day 5) of daily fluorouracil (600 mg/m2), repeated every 21 days. Subsequently, the patients received radiotherapy alone (induction chemotherapy in combination with radiotherapy [IC-RT] group) or concomitant cisplatin (30 mg/m2/week) with radiotherapy for 6 to 7 weeks (induction chemotherapy combined with chemoradiotherapy [IC-CCRT] group). Main Outcomes and Measures: The primary end point was 3-year progression-free survival (time from the initiation of therapy until the first indication of disease progression or death), with a noninferiority margin of 10%. The secondary end points included overall survival, locoregional failure-free survival, distant metastasis-free survival, response rate, and toxic effects. Results: A total of 383 patients (median [range] age, 48 [19-70] years; 100 women [26%]). Median follow-up time was 76 months (IQR, 70-89 months). The 3-year progression-free survival was 76.2% and 76.8% in the IC-RT (n = 193) and IC-CCRT groups (n = 190), respectively, in the intention-to-treat population, showing a difference of 0.6% (95% CI, -7.9% to 9.1%; P = .01 for noninferiority). Identical outcomes were reported in the per-protocol population. The incidence of grade 3 to 4 short-term toxic effects in the IC-RT group was less than the IC-CCRT group. No differences were observed in late toxic effects. Conclusions and Relevance: The results of this randomized clinical trial suggest that after induction chemotherapy for locoregionally advanced nasopharyngeal carcinoma, radiotherapy alone was noninferior to chemoradiotherapy in terms of 3-year progression-free survival. Trial Registration: ClinicalTrials.gov Identifier: NCT02434614.
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Neoplasias Nasofaríngeas , Humanos , Feminino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Cisplatino/uso terapêutico , Quimioterapia de Indução/métodos , Quimiorradioterapia/efeitos adversos , Progressão da Doença , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
Flocculent is commonly used in mining activities to improve the concentration of tailing slurry by enhancing the sedimentation process of small tailings particles. The presence of flocculent in thickened tailings is unavoidable, and it affects the heavy metal leaching performances and mechanical and rheological characteristics of tailing-based cemented paste backfill (CPB). This study is carried out to investigate the physicochemical and leachability of CPB amended with flocculants and lime-activated ground granulated blast-furnace slag (GGBS). The stabilized samples were subjected to a series of model tests, including toxicity characteristics leaching procedure (TCLP) and pH, unconfined compressive strength (UCS), scanning electron microscopy (SEM), and X-ray diffraction. Moreover, the CPB amended with anionic polyacrylamide (APAM) demonstrated better performance in terms of a decrease in heavy metal leachability besides higher mechanical strength than poly aluminum chloride (PAC) and poly ferric chloride (PFC) samples. Furthermore, the UCS results showed that increasing binder content up to 15% negatively influences strength improvement of all stabilized samples because of weak connections between soil particles and cementitious material, resulting in high leachability of heavy metals. The analysis of XRD and SEM showed that anionic polyacrylamide (APAM) cases exhibited more voluminous hydration products, resulting in a compact stabilized matrix and substantially reduced heavy metal leachability.
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Metais Pesados , Água , Água/química , Óxidos/química , Compostos de Cálcio/química , Metais Pesados/análiseRESUMO
Medical image segmentation faces current challenges in effectively extracting and fusing long-distance and local semantic information, as well as mitigating or eliminating semantic gaps during the encoding and decoding process. To alleviate the above two problems, we propose a new U-shaped network structure, called CFATransUnet, with Transformer and CNN blocks as the backbone network, equipped with Channel-wise Cross Fusion Attention and Transformer (CCFAT) module, containing Channel-wise Cross Fusion Transformer (CCFT) and Channel-wise Cross Fusion Attention (CCFA). Specifically, we use a Transformer and CNN blocks to construct the encoder and decoder for adequate extraction and fusion of long-range and local semantic features. The CCFT module utilizes the self-attention mechanism to reintegrate semantic information from different stages into cross-level global features to reduce the semantic asymmetry between features at different levels. The CCFA module adaptively acquires the importance of each feature channel based on a global perspective in a network learning manner, enhancing effective information grasping and suppressing non-important features to mitigate semantic gaps. The combination of CCFT and CCFA can guide the effective fusion of different levels of features more powerfully with a global perspective. The consistent architecture of the encoder and decoder also alleviates the semantic gap. Experimental results suggest that the proposed CFATransUnet achieves state-of-the-art performance on four datasets. The code is available at https://github.com/CPU0808066/CFATransUnet.
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Aprendizagem , Semântica , Processamento de Imagem Assistida por ComputadorRESUMO
Previous researches indicate that the potent toxicity of cadmium hinders the efficacy of the microbial-induced carbonate precipitation (MICP) process for bioremediation of Cd2+ in aqueous environment. Increasing urea and calcium resource doses, introducing synergists, and utilizing urease-producing consortia can improve bio-immobilization performance of MICP. However, such measures may incur cost increases and/or secondary contamination. This study first verifies the substantial biotoxicity of Cd2+ for urease activity and then analyzes the practical limitation of traditional MICP using Bacillus pasteurii for bioremediation of Cd2+ in an aqueous environment containing 1-40 mM Cd2+ by a series tube tests and numerical simulation. Subsequently, a two-step MICP method, which separates urea hydrolysis and heavy metal precipitation, is introduced in this study to eliminate the inhibitory effect of heavy metal on urease activity. The concentrations of ammonium, Cd2+, and pH were monitored over time. The results indicate that the urease expression in B. pasteurii can be significantly inhibited by Cd2+ particularly at the concentration ranging from 10 to 40 mM, leading to pretty low efficacy of traditional MICP for bioremediation of Cd2+ (Cd2+ removal rate as low as 21.55-38.47% when the initial Cd2+ concentration = 40 mM). In contrast, when the two-step MICP method is applied, the Cd2+ can be almost completely immobilized, even though the concentration ratio of urea to Cd2+ is as low as 1.5:1.0, which is close to the theory minimum concentration ratio for the complete precipitation of carbonate to cadmium ions(1.0:1.0). Therefore, the cost-effective, environmentally sustainable, and straightforward two-step MICP method holds great potential for application in the bioremediation of Cd2+-contaminated solutions in high concentration.
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Cádmio , Metais Pesados , Carbonato de Cálcio , Urease , Carbonatos , Ureia , Água , Precipitação QuímicaRESUMO
HfO2 films are widely used for optical coatings due to the high refractive index and low absorption, especially in the ultraviolet (UV) band. In this work, HfO2 film samples were prepared with the optimized assistant source power and deposition temperature by dual-ion beam sputtering (DIBS), followed by annealing treatments in vacuum and atmosphere, respectively. For samples with different annealing temperatures from 200 to 450 °C, the microstructure, morphology, film stress and optical properties from 200 to 1000â nm were systematically investigated. A monoclinic phase, a refractive index inhomogeneity along the film thickness and an absorption of shoulder-shape in the 250-300â nm band were found in the as-deposited samples. For samples annealed in vacuum, 400 °C annealing leaded to more oxygen defects, which in turn caused aggravated UV absorption. For samples annealed in atmosphere, the shoulder-shaped absorption weakened obviously above 300 °C annealing, which was suspected due to the reduction of oxygen defects during the crystallization process with sufficient oxygen. Scattering loss was investigated and found negligible for as-deposited and annealed samples. Additionally, film stress varied from compressive state to tensile state with increasing annealing temperature, and the zero-stress temperature is between 300-350 °C, which is due to the obvious crystallization behavior. Production methods and physical mechanisms for low absorption and scattering loss DIBS deposited HfO2 films were proposed and discussed in detail.
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Birefringence is at the heart of photonic applications. Layered van der Waals materials inherently support considerable out-of-plane birefringence. However, funnelling light into their small nanoscale area parallel to its out-of-plane optical axis remains challenging. Thus far, the lack of large in-plane birefringence has been a major roadblock hindering their applications. Here, we introduce the presence of broadband, low-loss, giant birefringence in a biaxial van der Waals materials Ta2NiS5, spanning an ultrawide-band from visible to mid-infrared wavelengths of 0.3-16 µm. The in-plane birefringence Δn ≈ 2 and 0.5 in the visible and mid-infrared ranges is one of the highest among van der Waals materials known to date. Meanwhile, the real-space propagating waveguide modes in Ta2NiS5 show strong in-plane anisotropy with a long propagation length (>20 µm) in the mid-infrared range. Our work may promote next-generation broadband and ultracompact integrated photonics based on van der Waals materials.
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Biphenylene networks typically exhibit a metallic electronic nature, while hydrogenation can open the band gap changing it to a semiconductor. This property makes hydrogenated biphenylene a promising candidate for use in semiconductor optoelectronic materials and devices. In this work, three representative configurations of hydrogenated biphenylene, denoted by α, ß and γ, were investigated. The structural, mechanical, electronic, and optical properties of these hydrogenated biphenylene configurations were calculated by first-principles calculations. Band gaps with HSE correction were 4.69, 4.42 and 4.39 eV for α, ß, and γ configurations, respectively. Among these three configurations, ß presents the best electronic performance and special elastic properties (negative Poisson's ratio), while γ exhibits the best elastic properties. In addition, we comprehensively analyze the mechanical properties of these configurations and provide evidence that hydrogenated biphenylene possibly exhibits a negative-Poisson's-ratio along the zigzag and armchair directions when hydrogen atoms are added to biphenylene in certain ways. Furthermore, although the electronic properties of γ are weaker than those of ß, they are also excellent. In addition, the binding energies of ß and γ are relatively lower, which indicates that ß and γ are more stable. Our findings demonstrate that the hydrogenated biphenylene is a promising material with significant application potential in optoelectronic devices.
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Broader spectra, lower reflectivity and higher reliability are the performance requirements for broadband antireflective (BBAR) films. In this work, a BBAR film structure was proposed, which maintains extremely low reflectivity, ultra-wide spectra, low polarization sensitivity and practical reliability. The BBAR film consists of a dense multilayer interference stack on the bottom and a nano-grass-like alumina (NGLA) layer with a gradient low refractive index distribution on the top. The film was deposited by atomic layer deposition, while the NGLA layer was formed by means of a hot water bath on Al2O3 layer. The top NGLA layer has extremely high porosity and ultra-low refractive index, along with extremely fragile structure. To surmount the fragility of NGLA layer, a sub-nano layer of SiO2 was grown by atomic layer deposition to solidify its structure and also to adjust the refractive index with different thicknesses of SiO2. Finally, in the wide wavelength range of 400-1100â nm, the average transmittance of the double-sided coated fused quartz reaches 99.2%. The absorption, light scattering, reliability and polarization characteristics of BBAR films were investigated. An optimized BBAR film with low polarization-sensitivity and improved reliability was realized, which should be potentially promising for application in optical systems.
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BACKGROUND AND PURPOSE: To investigate the safety and efficacy of hypofractionated plus chemotherapy in patients with initially distant metastatic nasopharyngeal carcinoma (mNPC). MATERIALS AND METHODS: Between May 2014 and June 2020, 35 patients initially diagnosed with mNPC were enrolled on prospective trial. The enrolled patients were assigned randomly to receive either hypofractionated plus chemotherapy (HFRT) or conventionally fractionated radiotherapy plus chemotherapy (CFRT). 60 Gy over 25 fractions was administered to the HFRT group (n = 17) and 69.96 Gy over 33 fractions was administered to the CFRT group (n = 18), both groups five times each week.Progression free survival (PFS) comprised the primary endpoint. Overall survival (OS), locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS), and acute and late toxicity comprised the secondary endpoints. RESULTS: Twenty-eight patients (seven were excluded) were enrolled. The 2-year PFS was 33.3% (HFRT group) versus 30.0% (CFRT group) (stratified hazard ratio (HR):1.09; 95% confidence interval (CI): 0.45-2.65, P = 0.843). The 2-year OS was 66.7% (HFRT group) versus with 62.5% (CFRT group) (stratified HR, 0.88; 95% CI; 0.31-2.51, P = 0.806). All patients experienced acute grade 1 or 2, skin toxicity, oral mucositis, difficulty swallowing, xerostomia, but no acute grade 3 or 4 toxicities. All patients had grade 1 late xerostomia. Two patients experienced hearing loss in the HFRT group (one grade 1 and one grade 3), and three patients experienced grade 1 hearing loss in the CFRT group. One patient developed mucosal necrosis in the HFRT group. CONCLUSION: Improving the balance between severe late toxicities and local control by appropriately reducing the total dose but increasing the fractionated dose has marked clinical significance for those patients.
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Neoplasias Nasofaríngeas , Xerostomia , Humanos , Fracionamento da Dose de Radiação , Carcinoma Nasofaríngeo/radioterapia , Estudos Prospectivos , Resultado do Tratamento , Recidiva Local de Neoplasia/radioterapia , Neoplasias Nasofaríngeas/radioterapiaRESUMO
Photothermal therapy (PTT) is an emerging field where photothermal agents could convert visible or near-infrared (NIR) radiation into heat to kill tumor cells. However, the low photothermal conversion efficiency of photothermal agents and their limited antitumor activities hinder the development of these agents into monotherapies for cancer. Herein, we have fabricated an ultrasmall polyvinylpyrrolidone (PVP)-Fe-Cu-Ni-S (PVP-NP) nano-agent via a simple hot injection method with excellent photothermal conversion efficiency (â¼96%). Photothermal therapy with this nano-agent effectively inhibits tumor growth without apparent toxic side-effects. Mechanistically, our results demonstrated that, after NIR irradiation, PVP-NPs can induce ROS/singlet oxygen generation, decrease the mitochondrial membrane potential, release extracellular Fe2+, and consume glutathione, triggering autophagy and ferroptosis of cancer cells. Moreover, PVP-NPs exhibit excellent contrast enhancement according to magnetic resonance imaging (MRI) analysis. In summary, PVP-NPs have a high photothermal conversion efficiency and can be applied for MRI-guided synergistic photothermal/photodynamic/chemodynamic cancer therapy, resolving the bottleneck of existing phototherapeutic agents.
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Ferroptose , Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Povidona/farmacologia , Nanomedicina Teranóstica/métodos , Fotoquimioterapia/métodos , Fototerapia/métodos , Neoplasias/tratamento farmacológico , Autofagia , Nanopartículas/uso terapêutico , Linhagem Celular TumoralRESUMO
Over decades of research on photoluminescence (PL) of silicon quantum dots (Si-QDs), extensive exploratory experiments have been conducted to find ways to improve the photoluminescence quantum yield. However, the complete physical picture of Si-QD luminescence is not yet clear and needs to be studied in depth. In this work, which considers the quantum size effect and surface effect, the optical properties of Si-QDs with different sizes and surface terminated ligands were calculated based on first principles calculations. The results show that there are significant differences in the emission wavelength and emission intensity of Si-QD interface states connected by different ligands, among which the emission of silicon-oxygen double bonds is the strongest. When the size of the Si-QD increases, the influence of the surface effect weakens, and only the silicon-oxygen double bonds still localize the charge near the ligand, maintaining a high-intensity luminescence. In addition, the presence of surface dangling bonds also affects luminescence. This study deepens the understanding of the photoluminescence mechanism of Si-QDs, and provides a direction for both future improvement of the photoluminescence quantum efficiency of silicon nanocrystals and for fabricating silicon-based photonic devices.
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Gasification is one of the most promising approaches to accomplishing efficient utilization of biomass, nevertheless, it shows severe problems of low efficiency and syngas quality, which deserves further improvements. In this regard, deoxygenation-sorption-enhanced biomass gasification is proposed and experimentally explored using deoxidizer-decarbonizer materials (xCaO-Fe) for intensified hydrogen production. The materials follow the deoxygenated looping of Fe0-3e-âFe3+ as an electron donor and the decarbonized looping of CaO + CO2 â CaCO3 as a CO2 sorbent. Specifically, the H2 yield and CO2 concentration reach 7.9 mmol·g-1 biomass and 10.5 vol%, which increases by 311% and decreases by 75%, respectively, compared with conventional gasification, confirming the promotion effect of deoxygenation-sorption enhancement. Fe embedded within the CaO phase is successfully constructed with the formation of functionalized interface structure, affirming the strong interaction between CaO and Fe. This study brings in a new concept for biomass utilization via synergistic deoxygenation and decarbonization, which will substantially boost high-quality renewable hydrogen production.
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Dióxido de Carbono , Hidrogênio , Dióxido de Carbono/química , BiomassaRESUMO
People spend about 5-8 hours per day on phones, causing circadian disruption and eye fatigue, thus raising a great need for comfort and health. Most phones have eye protection modes, claiming a potential eye protection effect. To examine the effectiveness, we investigated the color quality, namely gamut area and just noticeable color difference (JNCD), and circadian effect, namely equivalent melanopic lux (EML) and melanopic daylight efficacy ratio (MDER), characteristics of two smartphones: iPhone 13 and HUAWEI P30, in normal and eye protection mode. The results show that the circadian effect is inversely proportional to color quality when the iPhone 13 and HUAWEI P30 changed from normal to eye protection mode. The gamut area changed from 102.51% to 82.5% sRGB and 100.36% to 84.55% sRGB, respectively. The EML and MDER decreased by 13 and 15, and, 0.50 and 0.38, respectively, affected by the eye protection mode and screen luminance. The EML and JNCD results in different modes show that the eye protection mode benefits the nighttime circadian effect at the cost of the image quality. This study provides a way to precisely assess the image quality and circadian effect of displays and elucidates the tradeoff relationship between them.