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Long non-coding RNA (lncRNA) serves as a vital regulator of bone metabolism, but its role in pathologically overactive osteoclast differentiation remains elusive. Here, we identify lncRNA Dancr (Differentiation Antagonizing Non-protein Coding RNA) as a critical suppressor of osteoclastogenesis and bone resorption, which is down-regulated in response to estrogen deficiency. Global or osteoclast-specific Dancr Knockout mice display significant trabecular bone deterioration and enhanced osteoclast activity, but minimal alteration of bone formation. Moreover, the bone-targeted delivery of Dancr by Adeno-associated viral remarkably attenuates ovariectomy-induced osteopenia in mice. Mechanistically, Dancr establishes a direct interaction with Brahma-related gene 1 to prevent its binding and preserve H3K27me3 enrichment at the nuclear factor of activated T cells 1 and proliferator-activated receptor gamma coactivator 1-beta promoters, thereby maintaining appropriate expression of osteoclastic genes and metabolic programs during osteoclastogenesis. These results demonstrate that Dancr is a key molecule maintaining proper osteoclast differentiation and bone homeostasis under physiological conditions, and Dancr overexpression constitutes a potential strategy for treating osteoporosis.
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Factores de Transcripción NFATC , Osteogénesis , ARN Largo no Codificante , Factores de Transcripción , Animales , Femenino , Ratones , Homeostasis , Ratones Noqueados , Factores de Transcripción NFATC/genética , Osteoclastos , Osteogénesis/genética , ARN Largo no Codificante/genética , Factores de Transcripción/genéticaRESUMEN
As a plant-specific transcription factor, lateral organ boundaries domain (LBD) protein was reported to regulate plant growth and stress response, but the functional research of subfamily II genes is limited. SlMYC2, a master regulator of Jasmonic acid response, has been found to exhibit high expression levels in fruit and has been implicated in the regulation of fruit ripening and resistance to Botrytis. However, its role in fruit expansion remains unknown. In this study, we present evidence that a subfamily II member of LBD, namely SlLBD40, collaborates with SlMYC2 in the regulation of fruit expansion. Overexpression of SlLBD40 significantly promoted fruit growth by promoting mesocarp cell expansion, while knockout of SlLBD40 showed the opposite result. Similarly, SlMYC2 knockout resulted in a significant decrease in cell expansion within the fruit. Genetic analysis indicated that SlLBD40-mediated cell expansion depends on the expression of SlMYC2. SlLBD40 bound to the promoter of SlEXPA5, an expansin gene, but did not activate its expression directly. While, the co-expression of SlMYC2 and SlLBD40 significantly stimulated the activation of SlEXPA5, leading to an increase in fruit size. SlLBD40 interacted with SlMYC2 and enhanced the stability and abundance of SlMYC2. Furthermore, SlMYC2 directly targeted and activated the expression of SlLBD40, which is essential for SlLBD40-mediated fruit expansion. In summary, our research elucidates the role of the interaction between SlLBD40 and SlMYC2 in promoting cell expansion in tomato fruits, thus providing novel insights into the molecular genetics underlying fruit growth.
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Frutas , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Solanum lycopersicum , Factores de Transcripción , Solanum lycopersicum/genética , Solanum lycopersicum/crecimiento & desarrollo , Solanum lycopersicum/metabolismo , Frutas/genética , Frutas/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genéticaRESUMEN
Over the past 10,000 years, tomato species have undergone both unintentional and intentional selection to enhance their favorable traits for human consumption and manufacturing. These selection processes have significantly influenced the genomes of tomato species and have played a critical role in improving tomato varieties. In this review, we summarize recent advances in tomato genome sequencing, explore the impact of human-driven selection, and recapitulate key genes associated with important agronomic traits in tomato breeding. We provide several examples of genomics-guided tomato breeding to highlight the potential of genome resources in facilitating tomato improvement. Furthermore, we elaborate the progress and strategies of tomato breeding through genome design and present how such efforts can help future enhancements of tomato to align with the demands of sustainability and evolving human societies.
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Genoma de Planta , Genómica , Fitomejoramiento , Solanum lycopersicum , Solanum lycopersicum/genética , Fitomejoramiento/métodos , Genómica/métodosRESUMEN
Non-invasive transcranial direct-current stimulation (tDCS) is a safe ischaemic stroke therapy. Cathodal bilateral tDCS (BtDCS) is a modified tDCS approach established by us recently. Because selenium (Se) plays a crucial role in cerebral ischaemic injury, we investigated whether cathodal BtDCS conferred neuroprotection via regulating Se-dependent signalling in rat cerebral ischaemia-reperfusion (I/R) injury. We first showed that the levels of Se and its transport protein selenoprotein P (SEPP1) were reduced in the rat cortical penumbra following I/R, whereas cathodal BtDCS prevented the reduction of Se and SEPP1. Interestingly, direct-current stimulation (DCS) increased SEPP1 level in cultured astrocytes subjected to oxygen-glucose deprivation reoxygenation (OGD/R) but had no effect on SEPP1 level in OGD/R-insulted neurons, indicating that DCS may increase Se in ischaemic neurons by enhancing the synthesis and secretion of SEPP1 in astrocytes. We then revealed that DCS reduced the number of injured mitochondria in OGD/R-insulted neurons cocultured with astrocytes. DCS and BtDCS prevented the reduction of the mitochondrial quality-control signalling, vesicle-associated membrane protein 2 (VAMP2) and syntaxin-4 (STX4), in OGD/R-insulted neurons cocultured with astrocytes and the ischaemic brain respectively. Under the same experimental conditions, downregulation of SEPP1 blocked DCS- and BtDCS-induced upregulation of VAMP2 and STX4. Finally, we demonstrated that cathodal BtDCS increased Se to reduce infract volume following I/R. Together, the present study uncovered a molecular mechanism by which cathodal BtDCS confers neuroprotection through increasing SEPP1 in astrocytes and subsequent upregulation of SEPP1/VAMP2/STX4 signalling in ischaemic neurons after rat cerebral I/R injury. KEY POINTS: Cathodal bilateral transcranial direct-current stimulation (BtDCS) prevents the reduction of selenium (Se) and selenoprotein P in the ischaemic penumbra. Se plays a crucial role in cerebral ischaemia injury. Direct-current stimulation reduces mitochondria injury and blocks the reduction of vesicle-associated membrane protein 2 (VAMP2) and syntaxin-4 (STX4) in oxygen-glucose deprivation reoxygenation-insulted neurons following coculturing with astrocytes. Cathodal BtDCS regulates Se/VAMP2/STX4 signalling to confer neuroprotection after ischaemia.
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Isquemia Encefálica , Daño por Reperfusión , Selenio , Accidente Cerebrovascular , Estimulación Transcraneal de Corriente Directa , Ratas , Animales , Isquemia Encefálica/terapia , Isquemia Encefálica/metabolismo , Neuroprotección/fisiología , Proteína 2 de Membrana Asociada a Vesículas , Selenoproteína P , Oxígeno/metabolismo , Daño por Reperfusión/prevención & control , Daño por Reperfusión/metabolismo , Glucosa/metabolismo , Proteínas Qa-SNARERESUMEN
The discovery of superconductivity in twisted bilayer graphene has reignited enthusiasm in the field of flat-band superconductivity. However, important challenges remain, such as constructing a flat-band structure and inducing a superconducting state in materials. Here, we successfully achieved superconductivity in Bi2O2Se by pressure-tuning the flat-band electronic structure. Experimental measurements combined with theoretical calculations reveal that the occurrence of pressure-induced superconductivity at 30 GPa is associated with a flat-band electronic structure near the Fermi level. Moreover, in Bi2O2Se, a van Hove singularity is observed at the Fermi level alongside pronounced Fermi surface nesting. These remarkable features play a crucial role in promoting strong electron-phonon interactions, thus potentially enhancing the superconducting properties of the material. These findings demonstrate that pressure offers a potential experimental strategy for precisely tuning the flat band and achieving superconductivity.
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To evaluate the risk of acquiring syphilis from a donated kidney, we evaluated kidney transplantation pairs from West China Hospital, Sichuan, China, during 2007-2022. Donor-derived syphilis was rare. Risk may be higher if donors have active syphilis and may be reduced if recipients receive ceftriaxone.
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Trasplante de Riñón , Sífilis , Donantes de Tejidos , Humanos , Trasplante de Riñón/efectos adversos , Sífilis/epidemiología , China/epidemiología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Factores de RiesgoRESUMEN
The mechanism of selenium in the UV photochemical vapor generation (PVG) process was investigated by the use of multiple analytical methods. It was found that the UV-induced photooxidation trapping of the generated volatile SeH2 should be responsible for the previous opinion of relative inertness of Se(VI) in PVG with formic acid. Furthermore, the formation of Se(IV) was found during the PVG process, and the comproportionation of Se(IV) with SeH2 and the photooxidation of Se(IV) into Se(VI) were investigated. Then, a preliminary model was proposed for the PVG process of Se(VI) and Se(IV) with low-molecular-weight organic acids. Then, a novel, simple, and green photocontrolled method without any photocatalyst was thus proposed for the nonchromatographic speciation analysis of Se(IV) and Se(VI), with a limit of detection of 0.2 and 5 ng/mL, respectively.
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The single-layer MXene fully demonstrates the advantages of 2D materials, especially catalytic, conductive, and mechanical properties. However, the high energy consumption and low efficiency faced by MXene in the divestiture process are still challenges that need to be solved urgently. In this article, dimension mismatch and collaborative stripping strategies are skillfully combined to easily realize the transformation from multi-layer MXene to single layer. In addition, the functionalized MXene@SiC@polyaniline (MXene@SiC@PANI) nano-hybrid materials are used as fillers to improve the thermal conductivity, flame retardant, and antibacterial properties of thermoplastic polyurethane (TPU). The surface temperature of TPU/MXene@SiC@PANI composites increased from 33.4 °C to 59.8 °C within 10 s. In addition, the antibacterial efficiency of TPU composites against Escherichia coli and Staphylococcus aureus is 69.6% and 88.9%, respectively. Compared with pure TPU, the peak heat release rate and total heat release are reduced by 71.4% and 34.6%, respectively. The flame-retardant mechanism of MXene hybrid materials is systematically discussed. It is worth noting that the introduction of PANI enhances the compatibility between the filler and the polymer, effectively maintaining the mechanical properties of the TPU itself. This work provides a convenient method for the multi-functional practical application of TPU.
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Transforming growth factor (TGF)-ß and toll-like receptors (TLRs) have been shown to independently modulate the proliferation of hepatocellular carcinoma (HCC). Since a direct cross-talk between these two signalling pathways in HCC has not been clearly described before, we aimed here to explore the possibility of such interaction. A human HCC tissue array (n = 20 vs. four control samples), human HCC samples (n = 10) and steatohepatitis-driven murine HCC samples (control, NASH and HCC; n = 6/group) were immunostained for TGFßR1, pSMAD2, TRAF6, IRAK1 and PCNA. The results were confirmed by immunoblotting. Effects of constant activation of the SMAD pathway by constitutive expression of ALK5 or knockdown of mediators of TLR signalling, IRAK1 and MyD88, on HCC proliferation, were investigated in the HCC cell line (HUH-7) after treatment with TGFß1 cytokine or TGFßR1 kinase inhibitor (LY2157299) using PCNA and MTS assay. TGFßR1 expression is decreased in human and murine HCC and associated with downregulated pSMAD2, but increased IRAK1, TRAF6 and PCNA staining. TGFßR1 kinase inhibition abolished the cytostatic effects of TGFß1 and led to the induction of IRAK1, pIRAK1 and elevated mRNA levels of TLR-9. Overexpression of ALK5 and knockdown of MyD88 or IRAK1 augmented the cytostatic effects of TGFß1 on HUH-7. In another epithelial HCC cell line, that is, HepG2, TGFßR1 kinase inhibitor similarly elevated cellular proliferation. There is a balance between the canonical SMAD-driven tumour-suppressing arm and the non-canonical tumour-promoting arm of TGFß signalling. Disruption of this balance, by inhibition of the canonical pathway, induces HCC proliferation through TLR signalling.
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Antineoplásicos , Carcinoma Hepatocelular , Citostáticos , Neoplasias Hepáticas , Animales , Humanos , Ratones , Carcinoma Hepatocelular/patología , Proliferación Celular , Neoplasias Hepáticas/patología , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Receptores Toll-Like/metabolismo , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
Plasmonic direct-write lithography (PDWL) provides a potential tool for the fabrication and manufacturing at the nano scale due to its high-resolution and low-cost. However, the shallow exposure depth hinders its practical application. Here, we incorporate the plasmonic slab lenses (PSLs) into PDWL to amplify and compensate evanescent waves, leading to improved light intensity, depth, resolution and better tolerance to the air gap beyond the near field optical lithography. Two typical plasmonic probes with different nanostructure and localized plasmonic resonance mechanisms are designed and fabricated as representatives, the local intensity enhancement of which mainly depend on the oscillations of transverse and longitudinal electric field components, respectively. Optimizations considering the PSL structure, material and the illuminating wavelength are performed to amplify different field components and figure out the best lithography configuration. Simulation results indicate that Ag-Ag cavity PSL and 355â nm illumination is the best combination for the lithography with bowknot aperture probe, while the semi-ring probe exhibits better performance under the condition of Ag-Al cavity PSL and 405â nm illumination. The semi-ring probe in combination with a plasmonic cavity, for instance, is demonstrated to enhance the light intensity by 4 times at the bottom layer of the photoresist compared to that without PSL and realize a lithography resolution of 23â nm. Our scheme is believed to boost the application of PDWL as a high-resolution and low-cost nanofabrication technology, and it may even serve as an alternative for the high-cost scanning method, such as focused ion beam and electron beam lithography.
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We present our studies on the adsorption, deprotonation, and reactions of 4,4â³-diethynyl-1,1':4',1â³-terphenyl on Cu(111) under ultrahigh-vacuum conditions using scanning tunneling microscopy combined with density functional theory calculations. Sequential annealing treatments induce deprotonation of pristine molecules followed by chemical reactions, resulting in branched nanostructures. Within the nanostructures, a previously unreported, double-spot linkage is observed. Our density functional theory calculations unravel that this linkage corresponds to a five-membered copper metallacycle.
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BACKGROUND: Off-targeted distribution of chemotherapeutic drugs causes severe side effects, further leading to poor prognosis and patient compliance. Ligand/receptor-mediated targeted drug delivery can improve drug accumulation in the tumor but it always attenuated by protein corona barriers. RESULTS: To address these problems, a radically different strategy is proposed that can leave the off-targeted drugs inactive but activate the tumor-distributed drugs for cancer-targeting therapy in a tumor microenvironment-independent manner. The feasibility and effectiveness of this strategy is demonstrated by developing an ultrasound (US)-activated prodrug-loaded liposome (CPBSN38L) comprising the sonosensitizer chlorin e6 (Ce6)-modified lipids and the prodrug of pinacol boronic ester-conjugated SN38 (PBSN38). Once CPBSN38L is accumulated in the tumor and internalized into the cancer cells, under US irradiation, the sonosensitizer Ce6 rapidly induces extensive production of intracellular reactive oxygen species (ROS), thereby initiating a cascade amplified ROS-responsive activation of PBSN38 to release the active SN38 for inducing cell apoptosis. If some of the injected CPBSN38L is distributed into normal tissues, the inactive PBSN38 exerts no pharmacological activity on normal cells. CPBSN38L exhibited strong anticancer activity in multiple murine tumor models of colon adenocarcinoma and hepatocellular carcinoma with no chemotherapy-induced side effects, compared with the standard first-line anticancer drugs irinotecan and topotecan. CONCLUSIONS: This study established a side-effect-evitable, universal, and feasible strategy for cancer-targeting therapy.
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Adenocarcinoma , Antineoplásicos , Neoplasias del Colon , Nanopartículas , Fotoquimioterapia , Profármacos , Humanos , Animales , Ratones , Liposomas , Profármacos/farmacología , Profármacos/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Adenocarcinoma/tratamiento farmacológico , Neoplasias del Colon/diagnóstico por imagen , Neoplasias del Colon/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Nanopartículas/metabolismo , Fármacos Fotosensibilizantes/uso terapéutico , Microambiente TumoralRESUMEN
BACKGROUND: Computed tomography (CT) is widely in clinics and is affected by metal implants. Metal segmentation is crucial for metal artifact correction, and the common threshold method often fails to accurately segment metals. PURPOSE: This study aims to segment metal implants in CT images using a diffusion model and further validate it with clinical artifact images and phantom images of known size. METHODS: A retrospective study was conducted on 100 patients who received radiation therapy without metal artifacts, and simulated artifact data were generated using publicly available mask data. The study utilized 11,280 slices for training and verification, and 2,820 slices for testing. Metal mask segmentation was performed using DiffSeg, a diffusion model incorporating conditional dynamic coding and a global frequency parser (GFParser). Conditional dynamic coding fuses the current segmentation mask and prior images at multiple scales, while GFParser helps eliminate high-frequency noise in the mask. Clinical artifact images and phantom images are also used for model validation. RESULTS: Compared with the ground truth, the accuracy of DiffSeg for metal segmentation of simulated data was 97.89% and that of DSC was 95.45%. The mask shape obtained by threshold segmentation covered the ground truth and DSCs were 82.92% and 84.19% for threshold segmentation based on 2500 HU and 3000 HU. Evaluation metrics and visualization results show that DiffSeg performs better than other classical deep learning networks, especially for clinical CT, artifact data, and phantom data. CONCLUSION: DiffSeg efficiently and robustly segments metal masks in artifact data with conditional dynamic coding and GFParser. Future work will involve embedding the metal segmentation model in metal artifact reduction to improve the reduction effect.
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Artefactos , Metales , Fantasmas de Imagen , Prótesis e Implantes , Tomografía Computarizada por Rayos X , Humanos , Tomografía Computarizada por Rayos X/métodos , Estudios Retrospectivos , AlgoritmosRESUMEN
BACKGROUND: PM2.5 can induce and aggravate the occurrence and development of cardiovascular diseases (CVDs). The objective of our study is to estimate the causal effect of PM2.5 on mortality rates associated with CVDs using the instrumental variables (IVs) method. METHODS: We extracted daily meteorological, PM2.5 and CVDs death data from 2016 to 2020 in Binzhou. Subsequently, we employed the general additive model (GAM), two-stage predictor substitution (2SPS), and control function (CFN) to analyze the association between PM2.5 and daily CVDs mortality. RESULTS: The 2SPS estimated the association between PM2.5 and daily CVDs mortality as 1.14% (95% CI: 1.04%, 1.14%) for every 10 µg/m3 increase in PM2.5. Meanwhile, the CFN estimated this association to be 1.05% (95% CI: 1.02%, 1.10%). The GAM estimated it as 0.85% (95% CI: 0.77%, 1.05%). PM2.5 also exhibited a statistically significant effect on the mortality rate of patients with ischaemic heart disease, myocardial infarction, or cerebrovascular accidents (P < 0.05). However, no significant association was observed between PM2.5 and hypertension. CONCLUSION: PM2.5 was significantly associated with daily CVDs deaths (excluding hypertension). The estimates from the IVs method were slightly higher than those from the GAM. Previous studies based on GAM may have underestimated the impact of PM2.5 on CVDs.
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Contaminantes Atmosféricos , Enfermedades Cardiovasculares , Material Particulado , Humanos , Material Particulado/efectos adversos , Material Particulado/análisis , Enfermedades Cardiovasculares/mortalidad , China/epidemiología , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales/efectos adversos , Masculino , Femenino , Contaminación del Aire/efectos adversos , Persona de Mediana EdadRESUMEN
The measurement process of ground shock wave overpressure is influenced by complex field conditions, leading to notable errors in peak measurements. This study introduces a novel pressure measurement model that utilizes the Rankine-Hugoniot relation and an equilateral ternary array. The research delves into examining the influence of three key parameters (array size, shock wave incidence angle, and velocity) on the precision of pressure measurement through detailed simulations. The accuracy is compared with that of a dual-sensor array under the same conditions. Static explosion tests were conducted using bare charges of 0.3 kg and 3 kg TNT to verify the numerical simulation results. The findings indicate that the equilateral ternary array shock wave pressure measurement method demonstrates a strong anti-interference capability. It effectively reduces the peak overpressure error measured directly by the shock wave pressure sensor from 17.73% to 1.25% in the test environment. Furthermore, this method allows for velocity-based measurement of shock wave overpressure peaks in all propagation direction, with a maximum measurement error of 3.59% for shock wave overpressure peaks ≤ 9.08 MPa.
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Little is known about encouraging help-seeking in non-English speaking settings and relatively little research has been directed to facilitate help-seeking among Chinese-speaking people. This study examined the effects of a multimedia intervention on barriers, attitudes, and intentions for seeking counseling in China. The multimedia intervention was informed by prior empirical research on models of help-seeking for counseling. A total of 200 participants were randomly assigned to one of the two conditions: (1) a help-seeking media-exposed intervention group and (2) a control group, who watched a hospital advertisement that was unrelated to mental health help-seeking. Results indicated that the intervention was effective at increasing both positive attitudes toward therapy and intentions to seek therapy. The intervention also improved participants' perceptions about treatment accessibility. This intervention is available and can be a resource for Chinese language populations (both within China and other countries), especially for immigrants, rural, and persons who might benefit from mental health treatments such as psychotherapy.
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Multimedia , Aceptación de la Atención de Salud , Humanos , Aceptación de la Atención de Salud/psicología , Salud Mental , Estudiantes/psicología , LenguajeRESUMEN
A method was developed to identify and trace the geographic sources of Erigeron breviscapus using high-resolution mass spectrometry and chemometrics. The representative samples were collected from the geographic area of Honghe Dengzhanhua and other areas in Yunnan province and Guizhou province. The data points could be determined well using the PCA and PLS-DA diagram. A total of 46 characteristic compounds were identified from Honghe Dengzhanhua and within Guizhou province, but 37 compounds were different from Honghe Dengzhanhua and other counties in Yunnan province. Two biomarkers were found from three regions. Their structures were inferred as 8-amino-7-oxononanoic acid and 8-hydroxyquinoline, and they had the same molecular composition. This may suggest that a possible synthesis pathway can be proven in the future.
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Erigeron , Espectrometría de Masas , Erigeron/química , Espectrometría de Masas/métodos , Quimiometría , China , Análisis de Componente PrincipalRESUMEN
Objective: A quality control (QC) system based on the electronic portal imaging device (EPID) system was used to realize the Multi-Leaf Collimator (MLC) position verification and dose verification functions on Primus and VenusX accelerators. Methods: The MLC positions were calculated by the maximum gradient method of gray values to evaluate the deviation. The dose of images acquired by EPID were reconstructed using the algorithm combining dose calibration and dose calculation. The dose data obtained by EPID and two-dimensional matrix (MapCheck/PTW) were compared with the dose calculated by Pinnacle/TiGRT TPS for γ passing rate analysis. Results: The position error of VenusX MLC was less than 1 mm. The position error of Primus MLC was significantly reduced after being recalibrated under the instructions of EPID. For the dose reconstructed by EPID, the average γ passing rates of Primus were 98.86% and 91.39% under the criteria of 3%/3 mm, 10% threshold and 2%/2 mm, 10% threshold, respectively. The average γ passing rates of VenusX were 98.49% and 91.11%, respectively. Conclusion: The EPID-based accelerator quality control system can improve the efficiency of accelerator quality control and reduce the workload of physicists.
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Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Planificación de la Radioterapia Asistida por Computador/métodos , Dosificación Radioterapéutica , Algoritmos , Calibración , Electrónica , Radioterapia de Intensidad Modulada/métodos , Radiometría/métodosRESUMEN
In this study, the degradation efficiency and mechanism of carbamazepine (CBZ), a typical emerging contaminant in water, in the UV/sulfite process were investigated. The effects of different concentrations of dissolved oxygen [ρ(DO)] on the degradation of CBZ by UV-activated sulfite were investigated. Additionally, under a simulated natural water environment-controlled initial ρ(DO) of (8.0 ±0.2) mg·L-1, the effects of different process parameters (sulfite dosages and reaction pH) and water environmental factors (the presence of HCO3-, Cl-, and humic acids) on the degradation of CBZ were comprehensively analyzed. The results showed that the UV/sulfite process efficiently degraded CBZ with a degradation rate of 85.3% during the 30 min reaction time and followed the pseudo-first order kinetic model with the constant of 0.055 7 min-1. Using the electron spin resonance detection, reactive species quenching tests, and the competition kinetics, the sulfate radicals (SO4-·) and hydroxyl radicals (·OH) in the UV/sulfite process were determined to be the main reactive species and were responsible for the degradation of CBZ with contribution rates of 43.9% and 56.1%, respectively. In addition, the degradation efficiency of CBZ decreased with the increasing concentration of HCO3-, and the presence of Cl- had little effect on the degradation of CBZ, whereas the presence of humic acids significantly inhibited the degradation of CBZ. Moreover, the accumulation of sulfate during the reaction was significantly lower than the limit of the Standard for Drinking Water (GB5749-2022). Additionally, the sulfite consumption rate constant was 0.004 4 min-1, which was significantly lower than the degradation rate constant of CBZ, indicating that sulfite could be activated efficiently by UV light to degrade CBZ in water.
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Contaminantes Químicos del Agua , Purificación del Agua , Agua , Rayos Ultravioleta , Sustancias Húmicas , Contaminantes Químicos del Agua/análisis , Carbamazepina/análisis , Cinética , Sulfitos , Sulfatos , Purificación del Agua/métodos , Oxidación-ReducciónRESUMEN
We report the self-assembly of a monolayer metal-organic framework of Cu-benzenehexol (BHO) on a graphene/SiC substrate assisted by in situ Cu-catalyzed deprotonation reactions. The density functional theory calculations reveal that the free-standing framework is a semiconductor with a band gap of 0.485 eV. Interestingly, upon adsorption on the substrate, the Fermi level is up-shifted to the conduction band of the free-standing framework due to the n-doped graphene on SiC, while the other band structure features are largely preserved. The metallic nature corroborates the scanning tunneling microscopy images acquired near the Fermi level. This work demonstrates that the graphene substrate, which interacts weakly with the framework, can be used to tune the Fermi level of the metal-organic framework.