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This study aims to investigate how electroacupuncture regulates the learning and memory abilities of poststroke cognitive impairment (PSCI) rats through the TLR4/NF-κB/NLRP3 signaling pathway on the hippocampal microglia. Thirty male rats were randomly divided into three groups: sham surgery group, PSCI model group, and electroacupuncture group, with 10 rats in each group. Middle cerebral artery occlusion was used to establish the PSCI model. The Zea Longa method was used to score the rats' neurological function. Electroacupuncture was utilized for 21â days to improve PSCI. The learning and memory abilities of rats were tested using the Morris water maze. Hematoxylin-eosin staining and immunofluorescence were used to find the hippocampus' pathological changes. The concentration of interleukin-1ß, interleukin-6, tumor necrosis factor-α, and interleukin-18 were detected by ELISA. The mRNA expression levels of associated inflammatory corpuscles were measured by quantitative real-time PCR. The protein expression levels of TLR4, MyD88, NF-κB, and NLRP3 were measured using western blotting. Electroacupuncture improved not only the learning and memory abilities of PSCI rats but also hippocampal morphology. Electroacupuncture inhibited the activation of microglia and the TLR4/NF-κB/NLRP3 signaling pathway. Electroacupuncture also reduced proinflammatory factors and restrained the mRNA levels of NLRP3-associated inflammatory cytokines. Its mechanism was related to inhibiting the expression of the TLR4/NF-κB/NLRP3 signaling pathway, attenuating the release of inflammatory factors, and regulating the activation of hippocampal microglia in the brain.
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Electroacupuntura , Hipocampo , Microglía , FN-kappa B , Proteína con Dominio Pirina 3 de la Familia NLR , Ratas Sprague-Dawley , Transducción de Señal , Receptor Toll-Like 4 , Animales , Electroacupuntura/métodos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Receptor Toll-Like 4/metabolismo , Masculino , Hipocampo/metabolismo , Ratas , FN-kappa B/metabolismo , Microglía/metabolismo , Transducción de Señal/fisiología , Memoria/fisiología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/terapia , Infarto de la Arteria Cerebral Media/terapia , Infarto de la Arteria Cerebral Media/metabolismoRESUMEN
Aluminum (Al) exposure significantly interferes with the energy supply in astrocytes, which may be a potential mechanism of Al-induced neurotoxicity. This study was designed to explore the mechanisms of Al-induced energy supply impairment in rat C6 astroglioma cell line. Aluminum-maltolate (Al(mal)3) (0.1 mM, 24 h) exposure significantly decreased brain-type creatine kinase (BCK) co-localization with the endoplasmic reticulum (ER) and resulted in mitochondrial dysfunctions, accompanied by a decrease in AMPK phosphorylation. The results of molecular docking showed that Al(mal)3 increased BCK's hydrophobicity and hindered the localization movement of BCK between subcells·H2O2 co-administration was found to exacerbate mitochondrial dysfunction, Ca2+ dyshomeostasis, and apoptosis. After treated with Al(mal)3, additional oxidative stress contributed to BCK activity inhibition but did not promote a further decrease in AMPK phosphorylation. The activation of p-AMPK by its agonist can partially restore mitochondrial function, BCK activity, and ER-localized-BCK levels in Al(mal)3-treated astrocytes. In summary, Al exposure resulted in a sustained depletion of the mitochondrial and antioxidant systems, which was associated with reduced p-AMPK activity and decreased ER-localized-BCK levels in astrocytes. This study provides a theoretical basis for exploring the mechanisms of neurotoxicity induced by Al exposure.
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Proteínas Quinasas Activadas por AMP , Aluminio , Compuestos Organometálicos , Pironas , Ratas , Animales , Proteínas Quinasas Activadas por AMP/metabolismo , Aluminio/toxicidad , Peróxido de Hidrógeno , Simulación del Acoplamiento Molecular , Apoptosis , Estrés OxidativoRESUMEN
Purpose: To construct a training program for ICU nurses to manage artificial airway gasbags to prevent ventilator-associated pneumonia (VAP) and explore its application in ICU nurses. Methods: From January to March 2023, 17 experts were consulted using the Delphi method to construct the draft of the training program. 52 ICU nurses were selected from a third-level, first-class hospital in Henan Province. They received training using the program for 4 weeks. The training effects were evaluated by examining the theoretical knowledge, testing operation skills, and the ICU medical staff gasbag management knowledge-attitude-behavior questionnaire before and one week after the training in April 2023. Results: The coefficients of expert authority for the two round inquiries were 0.816 and 0.837, respectively. The coordination coefficient of expert opinions ranges from 0.2 to 0.3. The final training program for ICU nurses on managing artificial airway gasbags to prevent VAP was constructed and included 4 primary indicators, 25 secondary indicators, 47 tertiary indicators. After the training by the program, the scores of the ICU nurses' theoretical knowledge (before, 73.73 ± 8.54 VS after, 88.31 ± 6.29; t = 11.017, P<0.001) and technical operation (before, 75.29 ± 7.48 VS after, 86.92 ± 4.72; t = 8.986, P<0.001) were significantly increased. The total scores of the ICU nurses' knowledge-attitude-behavior on gasbag management (before, 76.67 ± 10.68 VS after, 109.04 ± 9.87; t = 19.916, P<0.001) were also significantly increased compared to the performance before training. Conclusion: The training program for ICU nurses on managing artificial airway gasbags to prevent VAP based on the Miller pyramid model is scientific and practical and can enhance the knowledge-attitude-behavior level of ICU nurses. This training program constructed in this study can be recommended and applied after further verification for the ICU nurses to manage the artificial airway gasbags in order to reducing the occurrence of the VAP in the clinical practice.
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Aggregating neighbor features is essential for point cloud neural network. In the existing work, each point in the cloud may inevitably be selected as the neighbors of multiple aggregation centers, as all centers will gather neighbor features from the whole point cloud independently. Thus, each point has to participate in the calculation repeatedly, generating redundant duplicates in the memory, leading to intensive computation costs and memory consumption. Meanwhile, to pursue higher accuracy, previous methods often rely on a complex local aggregator to extract fine geometric representation, further slowing down the processing pipeline. To address these issues, we propose a new local aggregator of linear complexity for point cloud analysis, coined as APP. Specifically, we introduce an auxiliary container as an anchor to exchange features between the source point and the aggregating center. Each source point pushes its feature to only one auxiliary container, and each center point pulls features from only one auxiliary container. This avoids the re-computation issue of each source point. To facilitate the learning of the local structure of point cloud, we use an online normal estimation module to provide explainable geometric information to enhance our APP modeling capability. Our built network is more efficient than all the previous baselines with a clear margin while still consuming a lower memory. Experiments on classification and semantic segmentation demonstrate that APP-Net reaches comparable accuracies to other networks. In the classification task, it can process more than 10,000 samples per second with less than 10GB of memory on a single GPU. We will release the code at https://github.com/MCG-NJU/ APP-Net.
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Using digital technologies in concurrently performing missing tooth implantation and preparation of remaining teeth is a solution to reduce the number of visits and improve efficiency. This paper proposes a digital process for simultaneously implanting and preparing teeth. It integrates implant surgical guide and 3D-printed tooth preparation guide into a single guide and completes guided implant placement and precise tooth preparation. Based on "repair-oriented" virtual implant planning, the implant surgical guide can improve the efficiency and predictability of implant placement, and its linear accuracy is about 1 mm. The tooth preparation guide precisely guides tooth preparation and restoration space visualization, ensuring the quality of the tooth preparation. The two guides have different design accuracy requirements, and thus their combination improves the overall guiding accuracy requirements. The concurrent application of the two guides minimizes the clinical operation time, number of visits, and economic burden of patients.
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Implantes Dentales , Cirugía Asistida por Computador , Humanos , Implantación Dental Endoósea , Impresión Tridimensional , Tecnología , Preparación del Diente , Diseño Asistido por Computadora , Imagenología Tridimensional , Tomografía Computarizada de Haz CónicoRESUMEN
Recently, in nanophotonics, thin metal films owing to the plasmon modes they support and their perovskite nanostructures exhibit novel optical properties, which have attracted considerable interest. Both the Förster resonant energy transfer (FRET) of the dopant-induced right-angled Yb3+-VPb-Yb3+ defect state and a pair of Yb3+ ions in all-inorganic perovskite nanocrystal (PeNC) CsPbCl3:Yb3+ quantum-cutting (QC) materials and the nanometal surface-energy transfer (NSET) of the excitons of PeNC-Ag nanoparticles (NPs) were investigated experimentally in CsPbCl3:Yb3+/PMMA/Ag/Si (CYAii = 1, 2, 3, 4, 5, 6), CsPbCl3:Yb3+/PMMA/Si (CYi), and CsPbCl3/PMMA/Ag/Si (CAi), representing three species of multilayer structures. It was found that due to the mediation of the Ag film and an increase in the interaction volume of donors-acceptors, FRET efficiencies increased from 26% to 66% as the spacer (or wave-guiding layer) thicknesses decreased from 63.7 to 17.8 nm. The energy-transfer efficiencies of CAi in the NSET in the surface-surface scheme followed a d-1.6-distance dependence. This distance dependence approached the d-2-distance dependence expected of a point-to-surface or 0D-2D energy transfer (ET). The ET in quantum cutting (QC) modulated by plasmons undoubtedly paves a way for improving the FRET and NSET performances of materials.
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In this work, we reported a novel preparation method for a proton exchange membrane (PEM) named, the direct electrostatic deposition method. In theory, any required thickness and size of PEM can be precisely controlled via this method. By direct electrostatic spraying of Nafion solution containing amino modified SiO2 nanoparticles onto a metal collector, a hybrid membrane of 30 µm thickness was fabricated. The DMFC assembled with a prepared ultrathin membrane showed a maximum power density of 124.01 mW/cm2 at 40 °C and 100% RH, which was 95.29% higher than that of Nafion. This membrane formation method provides potential benefits for the preparation of ultrathin PEMs.
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Obtaining optimal enamel bonding is a common recommendation to ensure the retention, edge closure, and clinical service life of porcelain veneers. Bonding surface is determined after tooth preparation. More or less dentin exposure often occurs due to the uneven thickness of the enamel. Identifying the enamel or dentin on the bonding surface and adopting the "selective etching" technique are useful to obtain the maximal bonding strength. Naked eye recognition in "selective etching" has uncertain results and is experience-based, whereas the proposed technique controls the preparation depth through the first target restoration space template to obtain the accurate enamel and dentin subarea. It is mapped to the second bonding template, depending on the treatment carried out on the enamel and dentin surface, to accurately predict the adhesion of porcelain veneers.
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The present article introduces a new digital workflow for the fabrication of an immediate implantation prothesis. With this technique, based on the surgical planning, the positioning tray and the restoration shell are predesigned and premanufactured together with the implant guide before the physical surgery. After implantation, the restoration shell is placed and bonded with a temporary abutment guided by the positioning tray, which acts as a type of tooth-borne device to guide the placement and bonding of the immediate restoration. The restoration shell acts as a type of hollowed out restoration in the tissue surface to improve the implantation error tolerance.
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Implantación Dental Endoósea , Prótesis Dental de Soporte Implantado , Humanos , Flujo de TrabajoRESUMEN
Objective: The objective of this study is to compare the characteristics of suicide attempts registered in general hospitals in urban and rural areas in China. Methods: From January 2007 to December 2011, suicide attempts registered in hospitals in five rural counties and in the Beijing Municipality were included. Univariate and multivariate analysis were used to compare the characteristics of rural and urban suicide attempts in China. Results: A total of 5,515 episodes of suicide attempts were included, 1,966 (35.6%) of them were from rural counties and 3,549 (64.4%) were from Beijing. Compared with urban counterparts, the rural suicide attempters had lower proportion of females (61.9% vs. 72.3%), more likely reporting previous suicide attempt history (56.9% vs. 16.4%), and staying in hospital for more than 1 day (81.5% vs. 44.6%). The most common methods of suicide attempts were pesticide ingestion in rural areas (52.1%) and taking medications in urban area (39.2%). Results of multivariate analysis indicated that suicide attempt registered in rural areas, pesticide ingestion, and previous suicide attempts history were associated with longer treatment in hospitals. Conclusions: Suicide attempts registered in rural areas were different from those in urban areas in China. It is essential to improve the equipment and ability of medical resuscitation for pesticide ingestion in rural hospitals in China.
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OBJECTIVE: This article describes a digital dental esthetic ceramic veneer treatment workflow using a stereolithographic template for teeth preparation. CLINICAL CONSIDERATIONS: We have presented the case of a 33-year-old woman with dental fluorosis who wanted an esthetic ceramic veneer treatment. A digital smile design was created on a virtual patient, and a virtual diagnostic wax-up was made. Based on the suggested ceramic material thickness, virtual teeth preparation was performed on the diagnostic wax-up. A special-teeth preparation template was then created digitally and fabricated using a stereolithographic technique. This template guided the teeth preparation using a special bur with a stopper. The veneers were fabricated by CAD/CAM and delivered good esthetics and function. CONCLUSIONS: The stereolithographic tooth reduction template helps realize digital restorative planning. It provides better control of the reduction depth of the labial and incisal preparation, making the operation simpler. CLINICAL SIGNIFICANCE: The digital dental esthetic ceramic veneer treatment workflow described here using a stereolithographic template for teeth preparation helped with the accurate control of reduction depth for minimally invasive teeth preparation, making the operation simpler, which is a significant improvement over the previous methods.
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Coronas con Frente Estético , Estética Dental , Adulto , Cerámica , Computadores , Porcelana Dental , Femenino , Humanos , Preparación del DienteRESUMEN
The minimum amount of tooth preparation that can be fully controlled is crucial in achieving long-term, stable, and effective aesthetic restoration, which is also a major difficulty in aesthetic restoration. The tooth preparation can be imple-mented efficiently and accurately through digital technology based on the fixed-deep hole guiding technology. Prior the actual tooth preparation, the technology first designs the virtual contour, layering, and virtual occlusion of the prosthesis on the computer. Then, virtual tooth preparation is carried out by cutting back according to the virtual prosthesis. Next, the virtual drilling operation plan is designed according to the shape of the virtual tooth preparation and the contour of the abutment tooth. Finally, the tooth preparation guide plate is designed and printed in 3D. It realizes the whole process of quantitative and precise guidance of dental preparation, visualizes the restoration space, reduces the clinical operation time, and guarantees the quality of dental preparation. It also promotes the improvement of the teaching quality of digital practical exercises.
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Estética Dental , Diente , Placas Óseas , Impresión Tridimensional , Preparación del DienteRESUMEN
Identifying the ideal implantation site is important for the long-term stability and effectiveness of follow-up restorations. Implant surgical guide and navigation are used to determine the implantation site in clinic and improve the precision of implantation. However, due to difficulties in digital methods, such as multiple procedures, high cost, and actual accuracy of more than 1 mm, many physicians still prefer to operate with free hand. In preoperative, intraoperative, and postoperative procedures, time-saving and practical methods for implant site evaluation are lacking. In many cases, oral physicians found that the position deviates only by cone beam CT, which was costly to modify the position. In this article, we presented a precise implantation insertion technology that is guided by a measurable technique throughout the implantation application for all implant systems. This method was guided by a dynamic control measuring ruler, which functions together with the measuring and intraoperative locating rulers. The 3D space of the operative area was measured by a measuring ruler prior to operation, and the implant plan and quantitative guidance design were conducted according to the measured and cone beam CT data. The whole implantation process was guided by the dynamic control measuring ruler, and measuring verification results were also considered. This method can realize the quantification of the entire preoperative space analysis, intraoperative precise implantation guidance, and postoperative site measurement and evaluation. This practical technique also helps to adjust the position, improve the implantation accuracy and is suitable in generalizing dental implantation.
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Implantes Dentales , Cirugía Asistida por Computador , Diseño Asistido por Computadora , Tomografía Computarizada de Haz Cónico , Implantación Dental Endoósea , Imagenología Tridimensional , Planificación de Atención al PacienteRESUMEN
This article introduces a new, fully digital workflow for the preparation of a guiding template and the procedure of the clinical operation in which it is put to use. A step-by-step technique is described including the virtual CAD of the preparation, the design of the template, the restoration based on the contours of the virtual preparation, the tooth preparation guided by the template, and the bonding of the predesigned restoration. The design and manufacture of all the templates and restorations are completed before the clinical operation.
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Computadores , Preparación del Diente , Diseño Asistido por Computadora , Humanos , Flujo de TrabajoRESUMEN
3D printing technology can be used in prosthodontics to obtain detailed structures. The technique offers a possible supersession for the most conventional restorations technologies. Contemporary aesthetic restorations encounter difficulties in the consistency between the analysis and design stages and the clinical implementation stage. 3D printing transfers aesthetic designs to customize the finial restoration fabrication, which could be an appropriate optimization to the aformentioned problem. Meanwhile, 3D printing technology can be employed to manufacture target restoration space guide (TRS guide), which is a blueprint for the aesthetic ceramic restorations and presents a general functional and aesthetic situation of patients. The guidance provided by TRS guide ensures precision and minimal invasive operation in aesthetic restorations. These new digital technologies have revolutionized aesthetic rehabilitation. This paper introduces the application of 3D printing in aesthetic oral rehabilitation.
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Impresión Tridimensional , Cerámica , Estética Dental , Humanos , ProstodonciaRESUMEN
Tongmai formula (TMF) is a herbal preparation composed of three traditional Chinese medicinal materials: Puerariae Lobatae Radix (Gegen), Salviae Miltiorrhizae Radix et Rhizoma (Danshen) and Chuanxiong Rhizoma (Chuanxiong). It has been used to treat cardiovascular diseases for decades. To develop a reliable and convenient analytical method for a comprehensive determination of polyphenols in TMF and the ascertainment of their chemical correlations with its herbal components, a method combining high-performance liquid chromatography with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was developed and validated for rapid determination of 30 polyphenols in TMF and its three herbal components. The chromatographic separation was carried out on a Chromolith Fastgradient RP-18 endcapped 50-2 column using an optimized gradient elution. Statistical analysis of obtained data demonstrated that the method had a desirable linearity, precision, and accuracy, as well as excellent sensitivity. The obtained results indicated that, among the 30 polyphenols in TMF, 22 originated from Gegen, 6 originated from Danshen, and 2 originated from Chuanxiong. The major polyphenols in TMF have been identified as puerarin, mirificin, salvianolic acid B, salvianic acid A, 3'-hydroxypuerarin, 3'-methoxypuerarin, and salvianolic acid A, with a combined contribution of 19.2% of the preparation. The development and validation of this method will greatly facilitate future pharmacological studies of TMF and its herbal components, as well as polyphenols in cardiovascular therapies.
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Medicamentos Herbarios Chinos/química , Polifenoles/análisis , Cromatografía Líquida de Alta Presión/métodos , Estructura Molecular , Extractos Vegetales/análisis , Polifenoles/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodosRESUMEN
Tongmai granule (TM) is composed of Puerariae Lobatae Radix (Gegen), Salviae Miltiorrhizae Radix et Rhizoma(Danshen) and Chuanxiong Rhizoma(Chuanxiong). It has been used to treat ischemic cardio-cerebrovascular diseases for decades. For the purpose of elucidating its pharmacodynamic material foundation, the absorption and pharmacokinetic property of TM were investigated in acute myocardial ischemic model beagles. All serum samples were extracted before analysis with ethyl acetate after being acidified by hydrochloric acid. Under negative ESI detection mode, the chromatographic separation was carried out with monolithic C18 column for gradient elution. A simultaneous quantitative analysis was made on 15 polyphenols, including 8 from Gegen, 5 from Danshen and 2 from Chuanxiong, in 8.5 min. The validation result demonstrated the specificity, accuracy and precision of the method in line with the bioanalysis requirements. After TM solution was administrated to acute myocardial ischemic model beagles through duodenum injection, serum samples were collected after 6 h. The quantitative detection proved the prompt absorption of TM, all of the components were detectable in the blood samples 5 min later, and reached peak respectively at 0.18-3.83 h after administration. The components presented large variabilities. The most components were exposed in serum with puerarin and salvianic acid A, followed by 3'-methoxypuerarin, mirificin, and 3'-hydroxypuerarin. The study proves puerarin and salvianic acid A are dominating active components of TM in acute myocardial ischemic model beagles.
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Medicamentos Herbarios Chinos/farmacocinética , Isquemia Miocárdica/tratamiento farmacológico , Enfermedad Aguda/terapia , Animales , Cromatografía Líquida de Alta Presión , Perros , Medicamentos Herbarios Chinos/administración & dosificación , Femenino , Humanos , MasculinoRESUMEN
Human lung cancer is highly invasive and the most malignant among human tumors. Adenocarcinoma as a specific type of non-small cell lung cancer occurs with high frequency and is also highly resistant to radiation therapy. Thus, how to avoid radiation resistance and improve radiotherapy effectiveness is a crucial question. In the present study, human lung cancer A549 and H1299 cells were irradiated using γ-rays from a Co60 irradiator. Protein expression was detected by Western blotting. Cell cycle and apoptosis were measured by flow cytometry. Surviving fraction was determined by colony formation assay. γH2AX and 53BP1 foci formation were examined by fluorescence microscopy. In the results, we show that CHMP4C, a subunit of Endosomal sorting complex-III (ESCRT-III), is involved in radiation-induced cellular response. Radiation-induced Aurora B expression enhances CHMP4C phosphorylation in non-small cell lung cancer (NSCLC) cells, maintaining cell cycle check-point and cellular viability as well as resisting apoptosis. CHMP4C depletion enhances cellular sensitivity to radiation, delays S-phase of cell cycle and reduces ionizing radiation (IR)-induced γH2AX foci formation. We found that Aurora B targets CHMP4C and inhibition of Aurora B exhibits similar effects with silencing of CHMP4C in radioresistance. We also confirm that CHMP4C phosphorylation is elevated after IR both in p53-positive and-negative cells, indicating that the close correlation between CHMP4C and Aurora B signaling pathway in mediating radiation resistance is not p53 dependent. Together, our work establishes a new function of CHMP4C in radiation resistance, which will offer a potential strategy for non-small cell lung cancer by disrupting CHMP4C.
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Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Rayos gamma , Neoplasias Pulmonares/metabolismo , Tolerancia a Radiación , Apoptosis , Aurora Quinasa B/metabolismo , Línea Celular Tumoral , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Células Epiteliales/metabolismo , Células Epiteliales/efectos de la radiación , Histonas/metabolismo , Humanos , Sistemas de Mensajero Secundario , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
The previous works by our group (Chem. Commun., 2010, 46, 2304-2306; ACS Catal., 2013, 3, 405-412; Phys. Chem. Chem. Phys., 2013, 15, 14681-14688) have reported the near-infrared-driven photocatalysis of broadband semiconductor TiO2 or ZnO that was combined with upconverting luminescence particles to form a core-shell structure. However, the photocatalytic efficiency is low for this new type of photocatalysts. In this work, NaYF4:Yb,Tm/CdS/TiO2 composites for NIR photocatalysis were prepared by linking CdS and TiO2 nanocrystals on the NaYF4:Yb,Tm microcrystal surfaces. CdS and TiO2 were well interacted to form a heterojunction structure. The energy transfer between NaYF4:Yb,Tm and the semiconductors CdS and TiO2 was investigated by steady-state and dynamic fluorescence spectroscopy. The photocatalytic activities of the as-prepared composites were evaluated by the degradation of methylene blue in aqueous solution upon NIR irradiation. Significantly, it was found that the united adhesions of CdS and TiO2 on the NaYF4:Yb,Tm particle surfaces showed much higher catalytic activities than the individual adhesion of CdS or TiO2 on the NaYF4:Yb,Tm surfaces. This was attributed mainly to the effective separation of the photogenerated electron-hole pairs due to the charge transfer across the CdS-TiO2 interface driven by the band potential difference between them. The presented composite structure of upconverting luminescence materials coupled with narrow/wide semiconductor heterojunctions provides a new model for improved NIR photocatalysis.
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This study explores whether the declining prevalence of Keshan disease is associated with increasing selenium levels in Keshan disease areas in Heilongjiang province. Six counties endemic with Keshan disease and three non-endemic counties were selected as study areas. In each county, two townships and in each township one village were chosen in which to survey ten families about head hair, grain, and soil samples and to obtain demographic information. Selenium was measured with hydride generation-atomic fluorescence spectrometry. In each county endemic with Keshan disease, one of the villages was chosen to investigate the prevalence of the disease. We collected 534 head hair samples, 446 staple food samples, and 180 soil samples. The selenium levels of head hair and corn in the endemic counties were significantly lower than those in non-endemic counties. Family demographic information was homologous except for the composition of staple food. More residents in Keshan disease areas preferred flour and corn. The detection rate for latent Keshan disease had a significantly negative correlation with the corn selenium level in six counties endemic with Keshan disease. As the population in this region is still at risk for Keshan disease, selenium surveillance measures should be intensified.