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Graphene aerogel (GA) has important application potential as piezoresistive sensors due to its low density, high conductivity, high porosity, and good mechanical properties. However, the fabrication of GA-based sensors with good mechanical properties and excellent sensing performance is still challenging. Herein, liquid- metal-modified GAs (GA/LM) are proposed for the development of an excellent GA-based sensor. GA/LM with three-dimensional interconnected layered structure exhibits excellent compressive stress of 41â KPa and fast response time (<20â ms). While generally flexible GA composites cannot be compressed beyond 80 % strain without plastic deformation, GA/LM demonstrates a high compressive strength of 60â kPa under a strain of 90 %. A real-time pressure sensor was fabricated based on GA/LM-2 to monitor swallowing, pulse beating, finger, wrist and knee bending, and even plantar pressure during walking. These excellent features enable potential applications in health detection.
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CO-stripping experiments are employed as a highly structure-sensitive and in situ strategy to explore the mechanisms of plasmon-enhanced electrooxidation reactions. By using Pt-Au heterodimers as a model catalyst, the plasmon-induced current and potential changes on Pt and Au sites can be identified and explained.
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OBJECTIVES: To search for pathogenic gene of a family with non-syndromic tooth agenesis, and explore the possible pathogenesis. MATERIALS AND METHODS: A Chinese family with non-syndromic tooth agenesis was recruited and screened for the pathogenic variants by whole exome sequencing technology and co-segregation analysis. The subcellular localization of wild-type and mutant protein was detected by immunofluorescence assay. Cycloheximide chase assay was performed to examine the difference in degradation rate between mutant protein and wild-type one. Dual-luciferase reporter assays were conducted to explore the alterations of mutant protein in the regulation of downstream target genes. RESULTS: A novel missense variant of PAX9 (c.296C>A:p.A99D) was found in this family. Bioinformatics software showed ß-return and the random coil were shortened in the p.A99D. The variant did not affect the subcellular localization of PAX9, but the degradation rate of p.A99D was accelerated (p < 0.05). p.A99D inhibited the activation of downstream target gene BMP4 (p < 0.05). CONCLUSIONS: This novel variant expands the pathogenic gene spectrum. The variant impaired the protein structure, accelerated the degradation of protein, and inhibited the activation of the downstream target gene BMP4, an upstream molecule in the TGF-ß/BMP pathway, which may contribute to tooth agenesis in this family.
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An efficient and precise time-frequency analysis method for real-time ocean bottom seismometer (RTOBS) data in the South China Sea (SCS) is presented. Overcoming the limitations of conventional methods, the method involves temporal segmentation, unique frequency octaves, and Fourier transforms to generate power spectral density (PSD) and probability density function profiles. The method demonstrates superior precision, computational efficiency, and full-bandwidth (0 to Nyquist) capability compared to traditional techniques, as validated through theoretical and empirical evaluations. Applied to SCS RTOBS data, it unveils temporal PSD variations, shedding light on underwater noise sources like earthquakes, offshore blasting, ship-induced disturbances, and tidal effects. Establishing background noise levels in the SCS supports noise source categorization and ocean environment monitoring. Furthermore, comparing onshore and offshore seismic stations advances interdisciplinary research, fostering a comprehensive understanding of acoustics and seismology in the region.
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BACKGROUND: Due to the highly heterogeneity of the breast cancer, it would be desirable to obtain a non-invasive method to early predict the treatment response and survival outcome of the locally advanced breast cancer (LABC) patients undergoing neoadjuvant chemotherapy (NAC). This study aimed at investigating whether strain elastography (SE) can early predict the pathologic complete response (pCR) and recurrence-free survival (RFS) in LABC patients receiving NAC. METHODS: In this single-center retrospective study, 122 consecutive women with LABC who underwent SE examination pre-NAC and after one and two cycles of NAC enrolled in the SHPD001(NCT02199418) and SHPD002 (NCT02221999) trials between January 2014 and August 2017 were included. The SE parameters (Elasticity score, ES; Strain ratio, SR; Hardness percentage, HP, and Area ratio, AR) before and during NAC were assessed. The relative changes in SE parameters after one and two cycles of NAC were describe as ΔA1 and ΔA2, respectively. Logistic regression analysis and Cox proportional hazards model were used to identify independent variables associated with pCR and RFS. RESULTS: Forty-nine (40.2%) of the 122 patients experienced pCR. After 2 cycles of NAC, SR2 (odds ratio [OR], 1.502; P = 0.003) and ΔSR2 (OR, 0.013; P = 0.015) were independently associated with pCR, and the area under the receiver operating characteristic curve for the combination of them to predict pCR was 0.855 (95%CI: 0.779, 0.912). Eighteen (14.8%) recurrences developed at a median follow-up of 60.7 months. A higher clinical T stage (hazard ratio [HR] = 4.165; P = 0.005.), a higher SR (HR = 1.114; P = 0.002.) and AR (HR = 1.064; P < 0.001.) values at pre-NAC SE imaging were independently associated with poorer RFS. CONCLUSION: SE imaging features have the potential to early predict pCR and RFS in LABC patients undergoing NAC, and then may offer valuable predictive information to guide personalized treatment.
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Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Ultrassom , Estudos RetrospectivosRESUMO
Physical unclonable functions (PUFs) based on uncontrollable fabrication randomness are promising candidates for anticounterfeiting applications. Currently, the most popular optical PUFs are generally constructed from the scattering, fluorescent, or Raman phenomenon of nanomaterials. To further improve the security level of optical PUFs, advanced functions transparent to the above optical phenomenon have always been perused by researchers. Herein, we propose a new type of PUF based on the photothermal effect of gold nanoparticles, which shows negligible scattering, fluorescent, or Raman responses. The gold nanoparticles are randomly dispersed onto the surface of fused silica, which can enhance the photothermal effect and facilitate high contrast responses. By tuning the areal density of the gold nanoparticles, the optimized encoding capacity (2319) and the total authentication error probability (3.6428 × 10-24) are achieved from our PUF due to excellent bit uniformity (0.519) and inter Hamming distances (0.503). Moreover, the intra-Hamming distance (0.044) indicates the desired reliability. This advanced PUF with invisible features and high contrast responses provides a promising opportunity to implement authentication and identification with high security.
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With the development of the shipbuilding industry, it is necessary to improve tribological properties of polyether ether ketone (PEEK) as a water-lubricated bearing material. In this study, the sulfonated PEEK (SPEEK) with three distinct chemical structures was synthesized through direct sulfonated polymerization, and high fault tolerance and a controllable sulfonation degree ensured the batch stability. The tribological and mechanical properties of SPEEK with varying side groups (methyl and tert-butyl) and rigid segments (biphenyl) were compared after sintering in a vacuum furnace. Compared to the as-made PEEK, as the highly electronegative sulfonic acid group enhanced the hydration lubrication, the friction coefficient and wear rate of SPEEK were significantly reduced by 30% and 50% at least without affecting the mechanical properties. And lower steric hindrance and entanglement between molecular chains were proposed to be partially responsible for the lowest friction behavior of SPEEK with methyl side groups, making it a promising and competitive option for water-lubricated bearings.
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BACKGROUND: The reported prevalence rate of anxiety disorder in the paediatric population varies widely between different counties. Currently, there is no national epidemiological survey of childhood anxiety disorder in China. This study aims to investigate the national prevalence of anxiety disorder, the distribution profiles of different subtypes and its comorbidity rates among school students. METHODS: A nationwide epidemiological survey of mental disorders in school students aged 6-16 years was conducted. Participants were randomly recruited from five provinces in China. The Child Behavior Checklist was used to screen students at high risk for mental disorders. The final diagnosis was made based on the Diagnostic and Statistical Manual-IV. The point prevalence and comorbidity rate of anxiety disorder were calculated, and the difference between age, sex and socioeconomic status groups was also compared. RESULTS: Generalised anxiety disorder (GAD) was the most common anxiety disorder in school-attending children and adolescents, with a prevalence rate of 1.3% (95% CI: 1.2 to 1.3). Separation anxiety and specific phobia were more common in children than in adolescents. Girls had a higher prevalence of panic disorder (0.3% vs 0.2%, χ2=14.6, p<0.001) and agoraphobia (0.9% vs 0.8%, χ2=4.3, p=0.03) than that of boys. We found no significant difference between developed and less developed areas. Girls were more likely to have panic disorder and GAD than boys, with ratios of 2.13:1 and 1.01:1, respectively. The co-occurrence of anxiety disorder and attention-deficit and disruptive behaviour disorder was very common, ranging from 40% to 85%. CONCLUSIONS: Anxiety disorder was prevalent among school students in China, and comorbidity with attention-deficit and disruptive disorder was very common. The data imply that screening for anxiety disorder is needed in school settings. Policies should be adapted to provide psychological services to children and adolescents. A comprehensive assessment is recommended in clinical practice.
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Transtorno do Deficit de Atenção com Hiperatividade , Transtornos Fóbicos , Masculino , Feminino , Criança , Humanos , Adolescente , Prevalência , Transtornos Fóbicos/diagnóstico , Transtornos Fóbicos/epidemiologia , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , ComorbidadeRESUMO
The chiral discrimination of enantiomers is crucial for drug screening and agricultural production. Surface-enhanced Raman scattering (SERS) is proposed for discriminating enantiomers benefiting from chiral plasmonic materials. However, the mechanism of enantioselective SERS is unclear, and fluctuating SERS intensities may result in errors. Herein, this work demonstrates a reliable SERS substrate using chiral Au nanocrystals with finely modulated chiral fields and internal standards. Chiral electromagnetic fields are enhanced after modulation, which is conducive to increasing the difference in the enantiomeric SERS intensity, as evidenced by the experimental and simulation results. Furthermore, the SERS stability is improved by the corrective effect of the internal standards, and the relative standard deviation is significantly reduced. Using finely modulated chiral fields and internal standards, L- and D-phenylalanine exhibit a stable six times difference in SERS ratio. Theoretical simulations reveal that linearly polarized light can also excite the chiral fields of chiral Au nanocrystals, indicating non-chiral far-field light is converted into chiral near-field sources by chiral Au nanocrystals. Thus, the mechanism of enantioselective SERS can be elucidated by the scattering difference of chiral molecules in chiral near fields. This study will pave the way for the development of enantioselective SERS and related chiroptical technologies.
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Leaf petiole or stem strength is an important agronomic trait affecting the growth of underground organs as a channel for material exchange and plays a vital role in the quality and yield of crops and vegetables. There are two different types of petioles in lotus, floating leaf petioles and vertical leaf petioles; however, the internal difference mechanism between these petioles is unclear. In this study, we investigated the differences between the initial vertical leaf petioles and the initial floating leaf petioles based on RNA sequencing (RNA-seq), and >2858 differentially expressed genes were annotated. These genes were chiefly enriched in phenylpropanoid biosynthesis, which is the source of the lignin and cellulose in petioles and stems. Lignin biology-related gene NnHCT1 was identified, and subsequent biological function validation demonstrated that the transient overexpression of NnHCT1 significantly increased the lignin and cellulose contents in lotus petioles and tobacco leaves. In contrast, silencing NnHCT1 through virus-induced gene silencing significantly reduced petiole lignin synthesis. Additionally, differentially up-regulated MYB family transcription factors were identified using RNA-seq. Yeast-one-hybrid and dual-luciferase reporter assays demonstrated that MYB4 could bind to the NnHCT1 promoter and up-regulate NnHCT1 expression. These findings demonstrate the significant potential of NnHCT1 to enhance lignin synthesis, thereby improving stem or petiole resistance to stunting and explaining the need for the study of differential petiole relationships in plants.
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Regulação da Expressão Gênica de Plantas , Lignina , Nelumbo , Folhas de Planta , Proteínas de Plantas , Lignina/biossíntese , Lignina/genética , Nelumbo/genética , Nelumbo/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Celulose/biossíntese , Genes de PlantasRESUMO
The outstanding photoelectric properties of perovskites demonstrate extreme promise for application in X-ray detection. However, the soft lattice of the perovskite results in severe ionic migration for three-dimensional materials, limiting the operation stability of perovskite X-ray detectors. Although ligand-decorated nanocrystals (NCs) exhibit significantly higher stability than three-dimensional perovskites, defects remaining on the interface of NCs could still trigger halide migration under a high bias due to the incomplete ligand decoration. Furthermore, it is still challenging to realize sufficient thickness of absorption layers based on NCs for X-ray detectors through traditional methods. Herein, we develop a centimeter-size and millimeter-thick wafer based on CsPbBr3 NCs through isostatic pressing for X-ray detectors, in which the interfacial defects of NCs are remedied by CsPb2Br5 during aging of wafer in ambient humidity. The wafer shows outstanding sensitivity (200 µC Gyair-1 cm-2) and ultralow dark current drift (1.78 × 10-8 nA cm-1 s-1 V-1 @ 400 V cm-1). Moreover, it shows storage stability with negligible performance degradation for 60 days in ambient humidity. Thus, aging perovskite NC wafers for X-ray detection holds huge potential for next-generation X-ray imaging plates.
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This research aimed to devise and assess a mobile game therapy software for children with Attention-Deficit/Hyperactivity Disorder (ADHD), as well as evaluating its suitability and effectiveness in improving the cognitive ability of typically developing children. The study encompassed 55 children diagnosed with ADHD and 55 neurotypical children. Initial assessments involved ADHD-related scales, computerized tests for information processing, and physiological-psychological evaluations. After a 4-week home-based game intervention, participants underwent re-evaluation using baseline measures and provided feedback on treatment satisfaction. Considering the small proportion of study participants who dropped out, data was analyzed using both the Intention-to-Treat (ITT) analysis and the Per-protocol (PP) analysis. The trial was registered at ClinicalTrials.gov (NCT06181747). In ITT analysis, post-intervention analysis using linear mixed models indicated that the ADHD group improved significantly more than the neurotypical group particularly in Continuous Performance Test (CPT) accuracy (B = -23.92, p < 0.001) and reaction time (B = 86.08, p < 0.01), along with enhancements in anti-saccade (B = -10.65, p < 0.05) and delayed-saccade tasks (B = 0.34, p < 0.05). A reduction in parent-rated SNAP-IV scores was also observed (B = 0.43, p < 0.01). In PP analysis, paired-sample t-tests suggested that the ADHD group had significant changes pre- and post-intervention, in terms of CPT Accuracy (t = -7.62, p < 0.01), Anti-saccade task Correct Rate (t = -3.90, p < 0.01) and SNAP-IV scores (t = -4,64, p < 0.01). However, no significant changes post-intervention were observed in the neurotypical group. Survey feedback highlighted a strong interest in the games across both groups, though ADHD participants found the game more challenging. Parents of ADHD children reported perceived benefits and a willingness to continue the game therapy, unlike the neurotypical group's parents. The findings advocated for the integration of serious video games as a complementary tool in ADHD treatment strategies, demonstrating the potential to augment attentional abilities and alleviate clinical symptoms. However, a randomized controlled trial (RCT) is needed to further verify its efficacy.
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Transtorno do Deficit de Atenção com Hiperatividade , Estudos de Viabilidade , Jogos de Vídeo , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Masculino , Feminino , Aplicativos Móveis , Resultado do TratamentoRESUMO
Nowadays, two of the biggest obstacles restricting the further development of methanol fuel cells are excessive cost and insufficient catalytic activity of platinum-based catalysts. Herein, platinum nanoparticle supported graphene aerogel (Pt/3DGA) was successfully synthesized by a one-step hydrothermal self-assembly method. The loose three-dimensional structure of the aerogel is stabilized by a simple one-step method, which not only reduces cost compared to the freeze-drying technology, but also optimizes the loading method of nanoparticles. The prepared Pt/3DGA catalyst has a three-dimensional porous structure with a highly cross-linked, large specific surface area, even dispersion of Pt NPs and good electrical conductivity. It is worth noting that its catalytic activity is 438.4 mA/mg with long-term stability, which is consistent with the projected benefits of anodic catalytic systems in methanol fuel cells.. Our study provides an applicable method for synthesizing nano metal particles/graphene-based composites.
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Secondary organic aerosol (SOA) accounts for a large fraction of fine particulate matter (PM2.5), but the lack of vertical observations of SOA in the urban boundary layer (UBL) limits a comprehensive understanding of its sources and formation mechanisms. In this study, PM2.5 samples were simultaneously collected at 3 m, 118 m, and 488 m on the Canton Tower in Guangzhou during winter. Typical SOA tracers, including oxidation products of isoprene (SOAI), monoterpene (SOAM), sesquiterpene (SOAS), and toluene (ASOA), were investigated alongside meteorological parameters and gaseous/particulate pollutants. Total concentrations of SOA tracers showed an increasing trend with height, with daytime levels exceeding nighttime levels. C5-alkene triols and 2-methylglyceric acid displayed a significant increase with height, potentially affected by nighttime chemistry in the residual layer, determining the overall vertical trend of SOAI tracers. Concentrations of later-generation SOAM (SOAM_S) tracers also increased with height, while those of first-generation SOAM (SOAM_F) tracers decreased, indicating relatively aged SOAM in the upper layers. SOAS and ASOA tracers exhibited higher enhancement under polluted conditions, likely impacted by biomass burning and anthropogenic emissions. The yields of SOAI tracers varied with temperature in the vertical profile. The formation of SOAM_F tracers was negatively correlated with relative humidity, liquid water content, and pH, affecting their vertical distributions. The effect of O3 on SOA formation enhanced significantly with height, influenced by air mass transport, and likely contributed to the higher yields of SOA in the upper layer. However, at ground level, SOA formation was primarily driven by high local emissions of both NOx and volatile organic compounds. We also observed the roles of SO2 in SOA generation, particularly at 118 m. This study demonstrates the vertical diurnal characteristics of SOA tracers in the UBL, highlighting the varying effects of meteorological conditions and anthropogenic pollutants on SOA formation at different heights.
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Abstract Purpose: To investigate the effects of exenatide on renal injury in streptozotocin-induced diabetic rats. Methods: Fifty SD rats were randomly divided into normal control, model, exenatide-1, exenatide-2 and exenatide-3 groups, 10 rats in each group. The diabetic nephropathy model was constructed in later 4 groups. Then, the later 3 groups were treated with 2, 4 and 8 μg/kg exenatide for 8 weeks, respectively. The serum and urine biochemical indexes and oxidative stress and inflammatory indexes in renal tissue were determined. Results: Compared to the model group, in exenatide-3 group the serum fasting plasma glucose and hemoglobin A1c levels were significantly decreased, the fasting insulin level was significantly increased, the renal index and blood urea nitrogen, serum creatinine and 24 h urine protein levels were significantly decreased, the renal tissue superoxide dismutase and glutathione peroxidase levels were significantly increased, the malondialdehyde level was significantly decreased, and the renal tissue tumor necrosis factor alpha, interleukin 6, hypersensitive C-reactive protein and chemokine (C-C motif) ligand 5 levels were significantly decreased P<0.05). Conclusions: Exenatide can mitigate the renal injury in diabetic rats. The mechanisms may be related to its resistance of oxidative stress and inflammatory response in renal tissue.