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The goal of this work was to explore the total iron burden of cerebral microbleeds (CMBs) using a semi-automatic quantitative susceptibility mapping and to establish its effect on brain atrophy through the mediating effect of white matter hyperintensities (WMH). A total of 95 community-dwelling people were enrolled. Quantitative susceptibility mapping (QSM) combined with a dynamic programming algorithm (DPA) was used to measure the characteristics of 1309 CMBs. WMH were evaluated according to the Fazekas scale, and brain atrophy was assessed using a 2D linear measurement method. Histogram analysis was used to explore the distribution of CMBs susceptibility, volume, and total iron burden, while a correlation analysis was used to explore the relationship between volume and susceptibility. Stepwise regression analysis was used to analyze the risk factors for CMBs and their contribution to brain atrophy. Mediation analysis was used to explore the interrelationship between CMBs and brain atrophy. We found that the frequency distribution of susceptibility of the CMBs was Gaussian in nature with a mean of 201 ppb and a standard deviation of 84 ppb; however, the volume and total iron burden of CMBs were more Rician in nature. A weak but significant correlation between the susceptibility and volume of CMBs was found (r = -0.113, P < 0.001). The periventricular WMH (PVWMH) was a risk factor for the presence of CMBs (number: ß = 0.251, P = 0.014; volume: ß = 0.237, P = 0.042; total iron burden: ß = 0.238, P = 0.020) and was a risk factor for brain atrophy (third ventricle width: ß = 0.325, P = 0.001; Evans's index: ß = 0.323, P = 0.001). PVWMH had a significant mediating effect on the correlation between CMBs and brain atrophy. In conclusion, QSM along with the DPA can measure the total iron burden of CMBs. PVWMH might be a risk factor for CMBs and may mediate the effect of CMBs on brain atrophy.
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Carbon storage in the form of solid hydrate under seafloor has been considered to be promising for greenhouse gas control. Yet, open issues still remain on the role of the organic matters abundant in marine environments in the kinetics of hydrate formation; of particular interest is the involvement of the acid-dissolvable organic matters accompanying the acidification upon CO2 injection. In this work, the CO2 hydrate formation in the presence of the organic matters was in-situ monitored through the low-field nuclear magnetic resonance technique. It was found that the organic matters could kinetically promote the formation of CO2 hydrate; this effect was further enhanced by the sulfur-containing acid-dissolvable organic matters. Water in the large pores was preferentially consumed; the following water conversion facilitated by the organic matters would result in a fragmentation of the large pores into separated small pores isolated by the hydrate clusters. Consequently, a further enhancement of the gas-water contact is suggested as the existence of substantial hydrate patches could act as a mass transfer barrier. Our findings expand our understandings on the kinetics of CO2 hydrate formation in the presence of the organic matters and indicate the stability zone of gas hydrate a kinetically favorable geological setting for CO2 sequestration.
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Dióxido de Carbono , Água , CinéticaRESUMO
In this work, the electroreductive removal of bromate by a Pd1-In4/Al2O3 catalyst in a three-dimensional electrochemical reactor was investigated. A total of 96.4% of bromate could be efficiently reduced and completely converted into bromide within 30 min under optimized conditions. On the basis of the characterization results and kinetics analysis, a synergistic effect of Pd and In was observed, and Pd1-In4/Al2O3 had the highest reaction rate constant of 0.1275 min-1 (vs 0.0413, 0.0328, and 0.0253 min-1 for In/Al2O3, Pd/Al2O3, and Al2O3). The results of electron spin resonance and scavenger experiments confirmed that both direct electron transfer and indirect reduction by atomic H* were involved in the bromate removal process, while the direct reduction played a more important role. Moreover, the introduction of In could increase the zeta potential of Pd1-In4/Al2O3, facilitating bromate adsorption and its subsequent reduction on the catalyst. Finally, a reaction mechanism for bromate reduction by Pd1-In4/Al2O3 was proposed based on all the experimental results.
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Bromatos/química , Brometos , Adsorção , Catálise , CinéticaRESUMO
As a systematic research at basin scale, this study explored the composition and concentration characteristics of 16 priority polycyclic aromatic hydrocarbons (PAHs) in sediments, water, and suspended particulate matter (SPM) in the water systems (rivers, lakes, and reservoirs) in the Hai River Basin through literature review. The sources and the ecosystem risks of PAHs in the sediments in the entire basin were specially discussed with diagnostic ration, PAHs composition, and an improved risk quotient method. Results showed that the total concentration of PAHs varied from 99.65 to 25,303 ng g(-1) dry weight in sediments, from 51.0 to 559.1 ng L(-1) in water, and from 4528 to 51,080 ng g(-1) dry weight in SPM, respectively. The dominant PAHs in the three examined phases were 2-3 rings in most waterbodies. PAHs in the rivers were from mixed sources (petrogenic and pyrolytic inputs), whereas those in lakes and reservoirs were mainly from biomass combustion and petroleum combustion. PAHs in the entire basin exhibited moderate to high ecological risk, and the rivers (especially Hai River, Jiyun River, Chaobai River, and Beiyun River) suffered higher ecological risk than reservoirs and lakes. Most of the rivers with higher PAHs risk flow through or around megacity Beijing and Tianjin.
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Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Poluentes Químicos da Água/análise , China , Medição de Risco , Poluição Química da Água/estatística & dados numéricosRESUMO
Although ASIC4 is a member of the acid-sensing ion channel (ASIC) family, we have limited knowledge of its expression and physiological function in vivo. To trace the expression of this ion channel, we generated the ASIC4-knockout/CreERT(2)-knockin (Asic4(Cre) (ERT) (2)) mouse line. After tamoxifen induction in the Asic4(Cre) (ERT)(2)::CAG-STOP(floxed)-Td-tomato double transgenic mice, we mapped the expression of ASIC4 at the cellular level in the central nervous system (CNS). ASIC4 was expressed in many brain regions, including the olfactory bulb, cerebral cortex, striatum, hippocampus, amygdala, thalamus, hypothalamus, brain stem, cerebellum, spinal cord and pituitary gland. Colocalisation studies further revealed that ASIC4 was expressed mainly in three types of cells in the CNS: (i) calretinin (CR)-positive and/or vasoactive intestine peptide (VIP)-positive interneurons; (ii) neural/glial antigen 2 (NG2)-positive glia, also known as oligodendrocyte precursor cells; and (iii) cerebellar granule cells. To probe the possible role of ASIC4, we hypothesised that ASIC4 could modulate the membrane expression of ASIC1a and thus ASIC1a signaling in vivo. We conducted behavioral phenotyping of Asic4(Cre) (ERT)(2) mice by screening many of the known behavioral phenotypes found in Asic1a knockouts and found ASIC4 not involved in shock-evoked fear learning and memory, seizure termination or psychostimulant-induced locomotion/rewarding effects. In contrast, ASIC4 might play an important role in modulating the innate fear response to predator odor and anxious state because ASIC4-mutant mice showed increased freezing response to 2,4,5-trimethylthiazoline and elevated anxiety-like behavior in both the open-field and elevated-plus maze. ASIC4 may modulate fear and anxiety by counteracting ASIC1a activity in the brain.
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Canais Iônicos Sensíveis a Ácido/metabolismo , Ansiedade/metabolismo , Medo/fisiologia , Canais Iônicos Sensíveis a Ácido/genética , Anfetamina/toxicidade , Animais , Ansiedade/genética , Composição Corporal/efeitos dos fármacos , Composição Corporal/genética , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/genética , Antagonistas de Estrogênios/farmacologia , Agonistas de Aminoácidos Excitatórios/toxicidade , Medo/efeitos dos fármacos , Humanos , Hipercinese/induzido quimicamente , Ácido Caínico/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Sistema Nervoso/efeitos dos fármacos , Sistema Nervoso/metabolismo , Nociceptividade/efeitos dos fármacos , Nociceptividade/fisiologia , Convulsões/induzido quimicamente , Tamoxifeno/farmacologia , Fatores de TempoRESUMO
4,4'-Diaminodiphenylmethane (MDA) is a widely used compound in industries. Studies on the biodegradability of MDA are necessary for environmental hazard identification and risk assessment. Previous studies have suggested that MDA was not readily biodegradable. In the present study, three batches of biodegradation tests (OECD 301A, B, D and F tests) were performed on MDA in June, August and December of 2012. MDA was found to be readily biodegradable and produced colored intermediates in the 301A, B and F test systems. MDA biodegradation measurements were consistent among the three batches of tests. Differences in the extent of biodegradation determined in different methods originated from different test conditions and assessment endpoints. The 301D test has stringent test conditions and is usually performed on chemicals that are toxic to microorganisms, so the test results obtained from 301D tests are less meaningful for evaluating the biodegradability of MDA. The low MDA biodegradation measurements in the 301B tests compared to the 301A and F tests were due to the assessment method, which did not account for MDA incorporation into biomass in its calculation of CO2 formation rate. The differences in the biodegradation rates, as measured by the different OECD 301 test systems, could also be related to the structure and properties of the chemical. For test substances that can be assessed by all OECD 301 test methods, the highest biodegradation values may be obtained from the 301A and F test methods. This study provides new information to assess the environmental fate in the risk assessment of MDA.
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Compostos de Anilina/metabolismo , Carcinógenos/metabolismo , Biodegradação Ambiental , Biomassa , Organização para a Cooperação e Desenvolvimento Econômico , Medição de RiscoRESUMO
Exposure to environmental endocrine-disrupting chemical Bisphenol-A (BPA) is often associated with dysregulated immune homeostasis, but the mechanisms remain unclear. In the present study, the effects of BPA on the cytokines responses of human macrophages were investigated. Treatment with BPA increased pro-inflammation cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production, but decreased anti-inflammation cytokines interleukin-10 (IL-10) and transforming growth factor-ß (TGF-ß) production in THP1 macrophages, as well as in primary human macrophages. BPA effected cytokines expression through estrogen receptor α/ß (ERα/ß)-dependent mechanism with the evidence of ERα/ß antagonist reversed the expression of cytokines. We also identified that activation of extracellular regulated protein kinases (ERK)/nuclear factor κB (NF-κB) signal cascade marked the effects of BPA on cytokines expression. Our results indicated that BPA effected inflammatory responses of macrophages via modulating of cytokines expression, and provided a new insight into the link between exposure to BPA and human health.
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Compostos Benzidrílicos/toxicidade , Citocinas/biossíntese , Macrófagos/efeitos dos fármacos , Fenóis/toxicidade , Linhagem Celular Tumoral , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor alfa de Estrogênio/fisiologia , Humanos , Interleucina-10/antagonistas & inibidores , Interleucina-6/biossíntese , Macrófagos/metabolismo , NF-kappa B/biossíntese , NF-kappa B/fisiologia , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossínteseRESUMO
This paper introduced the significance parameters of the quality control of cold light source of endoscope, expounded the importance and necessity of quality control of cold light source; it investigated several manufacturers, analyzed and discussed the main causes of the cold light source uneven, in order to realized the standard management and effective supervision on the cold light source, at the end, the next step quality control work was brought out, which provide technical support for quality supervision of cold light source.
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Endoscópios/normas , Luz , Controle de QualidadeRESUMO
RATIONALE: Primary ovarian leiomyoma is a rare benign tumor. The exact histological origin and pathogenesis of primary ovarian leiomyoma are still unclear, while its preoperative imaging diagnosis is often challenging and prone to misdiagnosis. The study aims to elucidate the diagnosis of primary ovarian leiomyoma and to distinguish it from fibroma. PATIENT CONCERNS: A 34-year-old female was admitted to the hospital with complaints of pelvic mass found for one year. One years ago, the patient went to a local hospital for examination due to irregular menstruation. DIAGNOSES: The ultrasound report of the patient showed ovarian teratoma. The postoperative pathological results showed ovarian leiomyoma and calcification. INTERVENTIONS: The patient underwent laparoscopic right ovarian leiomyoma resection. OUTCOMES: The patient was discharged home three days after surgery. At the most recent follow-up (five months after operation) of the patients, ultrasound was performed and no abnormal echoes were suggested in the adnexal region. LESSONS: In the diagnosis of primary ovarian leiomyoma, our case emphasizes the importance of microscopic features as an effective approach to distinguish it from ovarian fibroma, leiomyosarcoma, and stromal tumors. Additionally, personalized treatment should be considered based on the patient age and fertility needs.
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Calcinose , Leiomioma , Neoplasias Ovarianas , Humanos , Feminino , Adulto , Leiomioma/patologia , Leiomioma/diagnóstico por imagem , Leiomioma/cirurgia , Leiomioma/diagnóstico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/cirurgia , Calcinose/patologia , Calcinose/diagnóstico por imagem , Calcinose/diagnóstico , Diagnóstico Diferencial , Ultrassonografia/métodos , Teratoma/patologia , Teratoma/diagnóstico por imagem , Teratoma/diagnóstico , Teratoma/cirurgia , Laparoscopia/métodosRESUMO
The imbalances of storage capacity and reaction kinetics between carbonaceous cathodes and zinc (Zn) anodes restrict the widespread application of Zn-ion hybrid capacitor (ZIHC). Structure optimization is a promising strategy for carbon materials to achieve sufficient Zn2+ storage sites and satisfied ion-electron kinetics. Herein, porous graphitic carbon nanosheets (PGCN) were simply synthesized using a K3[Fe(C2O4)3]- and urea-assisted foaming strategy with polyvinylpyrrolidone as carbon precursor, followed by activation and graphitization. Sufficient pores with well-matched pore sizes (0.80-1.94 nm) distributed across the carbon nanosheets can effectively shorten mass-transfer distance, promoting accessibility to active sites. A partially graphitic carbon structure with high graphitization degree can accelerate electron transfer. Furthermore, high nitrogen doping (7.2 at.%) provides additional Zn2+ storage sites to increase storage capacity. Consequently, a PGCN-based ZIHC has an exceptional specific capacity of 181 mAh g-1 at 0.5 A g-1, superb energy density of 145 Wh kg-1, and excellent cycling ability without capacity decay over 10,000 cycles. In addition, the flexible solid-state device assembled with PGCN exhibits excellent electrochemical performances even when bent at various angles. This study proposes a straightforward and economical strategy to construct porous graphitic carbon nanosheets with enhanced storage capacity and fast reaction kinetics for the high performance of ZIHC.
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Hip fracture, increasing exponentially with age, is osteoporosis's most severe clinical consequence. Intertrochanteric fracture, one of the main types of hip fracture, is associated with higher mortality and morbidity. The current research hotspots lay in improving the treatment effect and optimizing the secondary stability after intertrochanteric fracture surgery. Cortex buttress reduction is a widely accepted method for treating intertrochanteric fracture by allowing the head-neck fragment to slide and rigidly contact the femoral shaft's cortex. Medial cortical support is considered a more effective option in treating young patients. However, osteo-degenerations features, including bone weakness and cortical thickness thinning, affect the performance of cortex support in geriatric intertrochanteric fracture treatment. Literature focusing on the age-specific difference in cortex performance in the fractured hip is scarce. We hypothesized that this osteo-19 degenerative feature affects the performance of cortex support in treating intertrochanteric fractures between the young and the elderly. We established twenty models for the old and the young with intertrochanteric fractures and performed static and dynamic simulations under one-legged stance and walking cycle conditions. The von Mises stress and displacement on the femur, proximal femoral nail anti-rotation (PFNA) implant, fracture plane, and the cutting volume of cancellous bone of the femur were compared. It was observed that defects in the anterior and posterior cortical bone walls significantly increase the stress on the PFNA implant, the displacement of the fracture surface, and cause a greater volume of cancellous bone to be resected. We concluded that ensuring the integrity and alignment of the anterior and posterior cortical bones is essential for elderly patients, and sagittal support is recommended. This finding suggests that the treatment method for intertrochanteric fracture may differ, considering the patient's age difference.
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Constipation and frailty are associated with intestinal dysbiosis. This study aims to identify intestinal microbial signatures that can differentiate between constipated elders accompanied by frailty and those without frailty. We collected stool samples from 61 participants and conducted 16S rRNA gene sequencing. Constipated patients with frailty (Constipation_F) exhibited reduced gut microbial diversities compared to constipated patients without frailty (Constipation_NF) and healthy individuals (C). From differential genera, random forest models identified 14, 8, and 5 biomarkers for distinguishing Constipation_F from Constipation_NF, Constipation_F from C, and Constipation_NF from C, respectively. Functional analysis revealed that pathways (P381-PWY and PWY-5507) related to vitamin B12 synthesis were reduced in Constipation_F, which aligns with the decreased abundances of vitamin-B12-producing Actinomyces and Akkermansia in this group. Our study unveils substantial differences in gut microbiota between constipated elders with frailty and those without, underscoring the diagnostic and therapeutic potential of genera involved in vitamin B12 synthesis.
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To verify the advantages of Virtual Fixtures (VFs) by comparing the result of guide plate navigation (GPN) and VFs in robot-assisted osteotomy. Robot-assisted surgery has been extensively applied in traditional orthopedic surgeries. It fundamentally improves surgeries' cutting accuracy. In addition, many key techniques have been applied in bone cutting to increase the procedure's safety in various ways. In this paper, two robot-assisted osteotomy methods are proposed. Three operators with no osteotomy experience performed plane cutting with the assistance of a robot. GPN and VFs were applied to assist the Sawbones cutting. Each operator has five attempts using each method to perform bone cutting, distance errors and angular errors were recorded. The advantage of Sawbones is that there is no influence from soft tissues and blood. It can give a more precise measurement. The results show that both methods have high accuracy with the robot's assistance. VFs have higher accuracy in comparison with GPN. With GPN, the mean distance and angular error of the three operators were 2.974 ± 0.282 mm and 4.737 ± 0.254°. With VFs, the mean range and angular error of the three operators were 1.857 ± 0.349 mm and 2.24 ± 0.123°, respectively. VFs limited the robot's end in the planned area, increasing the accuracy and safety of robot-assisted osteotomy.
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BACKGROUND: To develop an automatic and reliable ultrasonic visual system for robot- or computer-assisted liposuction, we examined the use of deep learning for the segmentation of adipose ultrasound images in clinical and educational settings. METHODS: To segment adipose layers, it is proposed to use an Attention Skip-Convolutions ResU-Net (Attention SCResU-Net) consisting of SC residual blocks, attention gates and U-Net architecture. Transfer learning is utilised to compensate for the deficiency of clinical data. The Bama pig and clinical human adipose ultrasound image datasets are utilized, respectively. RESULTS: The final model obtains a Dice of 99.06 ± 0.95% and an ASD of 0.19 ± 0.18 mm on clinical datasets, outperforming other methods. By fine-tuning the eight deepest layers, accurate and stable segmentation results are obtained. CONCLUSIONS: The new deep-learning method achieves the accurate and automatic segmentation of adipose ultrasound images in real-time, thereby enhancing the safety of liposuction and enabling novice surgeons to better control the cannula.
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Aprendizado Profundo , Lipectomia , Humanos , Animais , Suínos , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador/métodos , UltrassonografiaRESUMO
Herein, three-dimensional activated graphitic carbon spheres (AGCS) were constructed by simultaneous activation-graphitization of Fe-tannic acid coordination spheres with the assistance of KOH. Nanosheets-assembled AGCS with complex intersecting channel system can expose more active sites for charge storage. Simultaneous activation-graphitization can relieve trade-off relationship between porosity and conductivity of carbon materials. Benefiting from multiple synergistic effects of large specific surface area (2069 m2 g-1), abundant ion-accessible micropores (>0.78 nm), good electronic conductivity (IG/ID = 1.11), and moderate amount of oxygen doping, the optimized AGCS-2 has favored ion and electron transfer channels. AGCS-2 based zinc-ion hybrid capacitor (ZIHC) displays a high specific capacity of 148.6 mA h g-1 (334 F g-1) at 0.5 A g-1, a remarkable energy density of 119.0 W h kg-1 at 1440 W kg-1, and superior cycling life with 96% capacity retention after 10,000 cycles. This simultaneous activation-graphitization strategy may open up a new avenue to design novel carbon spheres linking optimal pores and graphitic carbon structure for ZIHC application.
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Graphene-based composites are appealing as a new class of materials that hold great promise for many applications. In this paper, highly ordered, homogeneous graphene oxide-poly(vinyl alcohol) (GO-PVA) with different content of PVA membranes and reduced graphene oxide-poly(vinyl alcohol) (RGO-PVA) membrane at 75% loading of PVA in the presence of hydrazine hydrate solution are prepared by the self-assemble process at liquid/air interface. The as-prepared membranes were investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM), Ultraviolet-visible (UV-vis) spectroscopy and four-probe resistance measurements. It was shown that the free-standing GO-PVA and RGO-PVA membranes are thickness controlled and area adjustable. The GO-PVA membranes have excellent transparent. The electrical conductivity of RGO-PVA membranes was up to 0.6 S/m by the chemical reduction of hydrazine hydrate. The membranes would be promising for practical applications in future nanotechnology.
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PURPOSE: Surgical skill assessment has received growing interest in surgery training and quality control due to its essential role in competency assessment and trainee feedback. However, the current assessment methods rarely provide corresponding feedback guidance while giving ability evaluation. We aim to validate an explainable surgical skill assessment method that automatically evaluates the trainee performance of liposuction surgery and provides visual postoperative and real-time feedback. METHODS: In this study, machine learning using a model-agnostic interpretable method based on stroke segmentation was introduced to objectively evaluate surgical skills. We evaluated the method on liposuction surgery datasets that consisted of motion and force data for classification tasks. RESULTS: Our classifier achieved optimistic accuracy in clinical and imitation liposuction surgery models, ranging from 89 to 94%. With the help of SHapley Additive exPlanations (SHAP), we deeply explore the potential rules of liposuction operation between surgeons with variant experiences and provide real-time feedback based on the ML model to surgeons with undesirable skills. CONCLUSION: Our results demonstrate the strong abilities of explainable machine learning methods in objective surgical skill assessment. We believe that the machine learning model based on interpretive methods proposed in this article can improve the evaluation and training of liposuction surgery and provide objective assessment and training guidance for other surgeries.
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Lipectomia , Cirurgiões , Humanos , Competência Clínica , Aprendizado de Máquina , RetroalimentaçãoRESUMO
Using photothermal therapy to treat cancer has become an effective method, and the design of photothermal agents determines their performance. However, due to the major radiative recombination of a photogenerated electron in photothermal materials, the photothermal performance is weak which hinders their applications. In order to solve this issue, preventing radiative recombination and accelerating nonradiative recombination, which can generate heat, has been proved as a reasonable way. We demonstrated a Cu2MoS4@MXene nanocomposite with an obviously enhanced photothermal conversion efficiency (η = 87.98%), and this improvement can be attributed to the electron migration. Then, a mechanism is proposed based on the electron transfer regulatory effect and the localized surface plasmon resonance effect, which synergistically promote nonradiative recombination and generate more heat. Overall, our design strategy shows a way to improve the photothermal performance of Cu2MoS4, and this method can be extended to other photothermal agents to let them be more efficient in treating cancer.
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Background: The reproducibility of radiomic features is essential to lung cancer detection. This study aimed to investigate the reproducibility of radiomic features of pulmonary nodules between low-dose computed tomography (LDCT) and conventional-dose computed tomography (CDCT). Methods: A total of 105 patients with 119 pulmonary nodules [39 ground-glass nodules (GGNs) and 80 solid nodules] who underwent LDCT and CDCT were retrospectively studied between September 2019 and November 2020. Pulmonary nodules were manually segmented and 1,125 radiomic features (shape, first-order intensity, texture, wavelet, and Laplacian of the Gaussian features) were extracted from both LDCT and CDCT images. The concordance correlation coefficient (CCC) was used to evaluate the reproducibility of these radiomic features. Results: Of the 1,125 radiomic features considered, 35.5% (399 of 1,125) and 41.5% (467 of 1,125) were reproducible (CCC ≥0.85) for GGNs and solid nodules, respectively. The intensity, texture, and wavelet features of solid nodules were more reproducible than those of GGNs. The mean CCC values for intensity and texture features of solid nodules were of 0.85 and above, whereas the mean values for those of GGNs were of less than 0.85. After Gaussian kernel (σ =2) preprocessing, the CCC of intensity and texture features of GGNs improved from 0.77 to 0.90, and 84.9% (79 of 93) of the radiomic features were reproducible (mean CCC increase from 0.84±0.13 to 0.92±0.08 for intensity features, and from 0.75±0.15 to 0.89±0.11 for texture features). Wavelet features had the lowest CCCs for both GGNs and solid nodules. Conclusions: The majority of the radiomic feature classes of solid pulmonary nodules have a high level of reproducibility between LDCT and CDCT. However, LDCT should not be used as an alternative to CDCT in the radiomic study of GGNs.
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Various compounds with sulfur or diamine structure have been served as efficient reducing agents to convert graphene oxide to reduced graphene oxide. In this work, we used thiourea with both sulfur and diamine structure to synthesize reduced graphene oxide by the general wet chemical reduction method. The effective deoxygenation of graphene oxide was confirmed by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy analysis and Raman spectroscopy. The as-prepared reduced graphene oxide is consisted of few-layered (no more than seven) and over 60% single-layered graphene sheet determined by atomic force microscopy and transmission electron microscopy. It also exhibits good dispersion in organic solvents such as ethanol and N,N-dimethylformamide, which is useful for the further modification of graphene and preparation of novel nanocomposites. This newly found reducing agent is of low toxicity and nonvolatile, which makes the reduction much safer.