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BACKGROUND: This study was conducted to evaluate the feasibility and surgical outcomes of minimally invasive video-assisted thyroidectomy (MIVAT) and three remote-access approaches, namely the robotic bilateral axillo-breast approach (BABA-R), endoscopic breast-chest approach (BCA-E), and robotic gasless transaxillary approach (GTAA-R) in lateral neck dissection for papillary thyroid carcinoma, compared with conventional transcervical approach (CTA). METHODS: The literature search was conducted in the PubMed, EMBASE, and Cochrane Library databases, covering the period January 2000 to February 2024. A systematic review and network meta-analysis were performed to compare surgical feasibility, safety, and oncologic outcomes between approaches. RESULTS: Fourteen articles on lateral neck dissection in patients with papillary thyroid carcinoma were included after systematic screening. The number of removed and metastatic lateral lymph nodes, the extent of lateral neck dissection, the rate of transient recurrent laryngeal nerve palsy and hypoparathyroidism, serum-stimulated thyroglobulin levels, and recurrence were not significantly different between the MIVAT and three remote-access approaches. Additionally, these were comparable to those of the CTA. However, the MIVAT and remote-access approaches took a longer operative time but provided superior cosmetic outcomes compared to the CTA. CONCLUSION: Lateral neck dissection using the MIVAT and three remote-access approaches was feasible and comparable to CTA in the number of lymph nodes removed, complications, stimulated thyroglobulin level, and recurrence. The MIVAT and remote-access approaches lasted longer but provided significantly superior cosmetic outcomes compared to the CTA.
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A multifunctional nanoplatform was constructed in this work, with the goal of ameliorating the challenges faced with traditional cancer chemotherapy. Cisplatin (CP) was loaded into mesoporous polydopamine (mPDA) nanoparticles (NPs) with a drug loading of 15.8 ± 0.1 %, and MnO2 used as pore sealing agent. Finally, the NPs were wrapped with platelet membrane (PLTM). P-selectin on the PLTM can bind to CD44, which is highly expressed on the tumor cell membrane, so as to improve the targeting performance of the NPs. In addition, the CD47 on the PLTM can prevent the NPs from being phagocytosed by macrophages, which is conducive to immune escape. The final PLTM-CP@mPDA/MnO2 NPs were found to have a particle size of approximately 198 nm. MnO2 is degraded into Mn2+ in the tumor microenvironment, leading to CP release from the pores in the mPDA. CP both acts as a chemotherapy agent and can also increase the concentration of H2O2 in cells. Mn2+ can catalyze the conversion of H2O2 to OH, resulting in oxidative damage and chemodynamic therapy. In addition, Mn2+ can be used as a contrast agent in magnetic resonance imaging (MRI). In vitro and in vivo experiments were performed to explore the therapeutic effect of the NPs. When the concentration of CP is 30 µg/mL, the NPs cause approximately 50 % cell death. It was found that the PLTM-CP@mPDA/MnO2 NPs are targeted to cancerous cells, and in the tumor site cause extensive apoptosis. Tumor growth is thereby repressed. No negative off-target side effects were noted. MRI could be used to confirm the presence of the NPs in the tumor site. Overall, the nano-platform developed here provides cooperative chemotherapy and chemodynamic therapy, and can potentially be used for effective cancer treatment which could be monitored by MRI.
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Antineoplásicos , Plaquetas , Cisplatino , Indoles , Compuestos de Manganeso , Nanopartículas , Óxidos , Polímeros , Compuestos de Manganeso/química , Cisplatino/administración & dosificación , Cisplatino/farmacología , Cisplatino/química , Polímeros/química , Indoles/química , Indoles/administración & dosificación , Animales , Óxidos/química , Nanopartículas/química , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Humanos , Ratones , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Liberación de Fármacos , Porosidad , Ratones Endogámicos BALB C , Imagen por Resonancia Magnética , Portadores de Fármacos/química , Femenino , Peróxido de Hidrógeno , Tamaño de la Partícula , Ratones DesnudosRESUMEN
The designed synthesis of an S-scheme heterojunction has possessed a great potential for improving photocatalytic wastewater treatment by demonstrating increased the photoredox capacity and improved the charge separation efficiency. Here, we introduce the fabrication of a heterojunction-based photocatalyst comprising bismuth oxychloride (BiOCl) and bismuth-based halide perovskite (BHP) nanosheets, derived from metal-organic frameworks (MOFs). Our composite photocatalyst is synthesized through a one-pot solvothermal strategy, where a halogenation process is applied to a bismuth-based metal-organic framework (CAU-17) as the precursor for bismuth sourcing. As a result, the rod-like structure of CAU-17 transforms into well-defined plate and nanosheet architectures after 4 and 8 h of solvothermal treatment, respectively. The modulation of the solvothermal reaction time facilitates the establishment of an S-scheme heterojunction, resulting in an increase in the photocatalytic degradation efficiency of rhodamine B (RhB) and sulfamethoxazole (SMX). The optimized BiOCl/BHP composite exhibits superior RhB and SMX degradation rates, achieving 99.8% degradation of RhB in 60 min and 75.1% degradation of SMX in 300 min. Also, the optimized BiOCl/BHP composite (CAU-17-st-8h sample) exhibited the highest rate constant (k = 3.48 × 10-3 min-1), nearly 6 times higher than that of the bare BHP in the photocatalytic degradation process of SMX. The enhanced photocatalytic efficiency can be endorsed to various factors: (i) the in-situ formation of two-components BiOCl/BHP photocatalyst, derived from CAU-17, effectively suppresses the aggregation of pristine BHP and BiOCl particles; (ii) the S-scheme heterostructure establishes a closely-knit interfacial connection, thereby facilitating efficient pathways for charge separation/transfer; and (iii) the BiOCl/BHP heterostructure enhances its capacity to absorb visible light. Our investigation establishes an effective strategy for constructing heterostructured photocatalysts, offering significant potential for application in photocatalytic wastewater treatment.
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Bismuto , Compuestos de Calcio , Estructuras Metalorgánicas , Óxidos , Rodaminas , Titanio , Contaminantes Químicos del Agua , Bismuto/química , Titanio/química , Compuestos de Calcio/química , Óxidos/química , Catálisis , Contaminantes Químicos del Agua/química , Estructuras Metalorgánicas/química , Rodaminas/química , Fotólisis , Aguas Residuales/química , Procesos FotoquímicosRESUMEN
BACKGROUND: The oncologic safety and surgical completeness of remote-access thyroidectomies are not yet clearly established. This study evaluates the oncologic outcomes and surgical completeness of three prevalent remote-access thyroidectomies: the gasless transaxillary approach (GTAA), bilateral axillo-breast approach (BABA), and transoral approach (TOA), in comparison with conventional transcervical thyroidectomy (CTT). METHODS: Literature searches were conducted in PubMed, EMBASE, and the Cochrane Library databases, covering the period from 2000 to 2023. Network meta-analyses were performed on selected studies, focusing on recurrence and surgical completeness. Surgical completeness was assessed using stimulated serum thyroglobulin levels and the count of retrieved lymph nodes. RESULTS: The review included 48 studies, encompassing a total of 16,356 patients. The number of retrieved lymph nodes was comparable among BABA, TOA, and CTT, while GTAA might be less effective. Stimulated serum thyroglobulin levels showed no significant differences across the four groups. However, the proportion of patients with stimulated thyroglobulin levels below 1.0 ng/mL was significantly lower in GTAA compared to the other groups. The overall recurrence rates were 1.31% for CTT, 0.89% for GTAA, 0.62% for BABA, and 0% for TOA, with no significant differences in recurrence rates when adjusted for follow-up duration. CONCLUSIONS: This study demonstrated that the oncologic outcomes of GTAA, BABA, and TOA are comparable to those of CTT, based on recurrence rates. In terms of surgical completeness, BABA and TOA showed equivalence to CTT, whereas GTAA might be inferior to the other techniques.
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Tiroglobulina , Tiroidectomía , Humanos , Mama , Metaanálisis en RedRESUMEN
BACKGROUND: Depression is a mental disorder common worldwide. This study determined the relationships between demographics, health status, household parameters, and depression rates among working-age household heads. METHODS: We analyzed data from the Korea Welfare Panel Study Survey conducted in 2020. The 11-item version of the Center for Epidemiologic Studies Depression Scale was used to assess depression. Bivariate analyses and a multiple logistic regression model were used to evaluate the influence of these factors on depression among household heads. RESULTS: The overall prevalence of depression among working-age household heads was 11.69% (19.83% of females and 9.58% of males). The relative risk of depression was 1.71 times higher among the unemployed than among wage earners and 2.18 times higher among those with low income than among those with general income. The relative risk of depression was 3.23 times higher in those with poor health status than in those with good health, and 2.45 times more in those with severe disabilities than in those without disabilities. The rate of depression decreased with education level, number of family members, and presence of children but increased with the presence of the disabled or elderly. CONCLUSION: This study provides a comprehensive overview of depression among working-age household heads and identifies factors strongly associated with depression. These findings may have implications for policymakers to reduce the burden on and improve the quality of life of household heads.
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Transparent heaters (THs) find widespread application in various indoor and outdoor settings, such as LCD panels and motorcycle helmet visors. Among the materials used for efficient TH performance, the AgNW network stands out due to its high conductivity, substantial transmittance, and minimal solution requirement. Extensive research has been directed towards enhancing AgNW characteristics, focusing on smaller diameters and longer wires. In TH applications, the primary considerations include a rapid response and elevated temperature. Consequently, this research delves into investigating the impact of parameters like diameter, length, and density on random AgNW networks under varying applied voltages. The finite element method is employed for analyzing temperature changes in response to voltage application, particularly in scenarios involving small-scale setups with high-density and high-percolation AgNW networks. The results reveal a significant increase in the thermal transition rate, ranging from 28% to 36%, with varying densities in the random network. Within the same density, the AgNW network with larger diameters and lengths demonstrates the highest temperatures, aligning with previous calculations. Furthermore, a trade-off exists between optical properties in smaller diameters and electrical properties in larger diameters within a relatively narrow temperature range.
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This study aimed to compare surgical outcomes of transoral robotic thyroidectomy (TORT) and transoral endoscopic thyroidectomy vestibular approach (TOETVA), concurrently compared with conventional transcervical thyroidectomy (CTT). A network meta-analysis, comprising 23 studies, was performed in this study. The operative time of the CTT group was significantly shorter than that of the TOETVA and TORT groups. The hospital stay of the TOETVA group was significantly longer than that of the CTT group. Rates of transient recurrent laryngeal nerve palsy and total complications were higher in association with TOETVA than with TORT. No significant differences were found between the three groups in intraoperative blood loss, retrieved lymph nodes, postoperative pain, and other complications. Cosmetic satisfaction was significantly superior with TORT and TOETVA than with CTT. Compared with CTT, TOETVA and TORT showed superior cosmesis but no significant difference in surgical outcomes except for operative time and hospital stay.
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Cirugía Endoscópica por Orificios Naturales , Metaanálisis en Red , Procedimientos Quirúrgicos Robotizados , Tiroidectomía , Humanos , Tiroidectomía/métodos , Tiroidectomía/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos , Cirugía Endoscópica por Orificios Naturales/métodos , Cirugía Endoscópica por Orificios Naturales/efectos adversos , Tempo Operativo , Resultado del Tratamiento , Tiempo de Internación/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Femenino , Endoscopía/métodos , Endoscopía/efectos adversosRESUMEN
BACKGROUND: The extent of postoperative pain following transoral thyroidectomy is not well-understood and remains a subject of debate. This study aims to analyze and compare postoperative pain levels between patients undergoing transoral and conventional transcervical thyroidectomy. METHODS: A prospective evaluation on postoperative pain was conducted in 310 patients undergoing conventional thyroidectomy and 194 undergoing transoral thyroidectomy. Pain levels were evaluated using the numerical rating scale (NRS, ranging from 0 to 10) through preoperative and postoperative questionnaires at specified time points: 1, 3, and 6 days, and 1 and 3 months following surgery. Propensity score-matched analysis was carried out based on six covariates: sex, age, body mass index, extent of thyroidectomy, tumor size, and central neck dissection. RESULTS: After propensity score matching based on the six covariates, 121 patient pairs were identified from each group. Within this matched cohort, postoperative pain scores significantly worsened 1 day after surgery but showed progressive recovery up to 3 months post-surgery in both groups. The transoral group exhibited higher postoperative pain scores than the conventional group from day 1 (4.43 ± 2.6 vs. 3.11 ± 2.5, p < 0.001) to day 6 (1.76 ± 1.9 vs. 1.13 ± 1.6, p = 0.016) post-surgery, with no significant difference noted at 1 month. Among transoral procedures, pain scores were significantly higher for the endoscopic approach compared to the robotic approach on days 1 (5.52 ± 2.3 vs. 4.29 ± 2.3, p = 0.028) and 3 (3.52 ± 2.5 vs. 2.64 ± 2.0, p = 0.047) post-surgery. CONCLUSIONS: Postoperative pain was significantly higher in transoral thyroidectomy compared to conventional thyroidectomy up to 6 days post-surgery. Within the transoral group, the robotic procedure resulted in lower pain levels than the endoscopic approach during the early postoperative period.
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Procedimientos Quirúrgicos Robotizados , Robótica , Neoplasias de la Tiroides , Humanos , Tiroidectomía/efectos adversos , Tiroidectomía/métodos , Puntaje de Propensión , Dolor Postoperatorio/epidemiología , Dolor Postoperatorio/etiología , Dolor Postoperatorio/cirugía , Disección del Cuello/efectos adversos , Disección del Cuello/métodos , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Procedimientos Quirúrgicos Robotizados/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos , Estudios RetrospectivosRESUMEN
PURPOSE: The Self-Assessment Questionnaire for Cosmetic Outcomes (SAQCO) was developed by us to evaluate the cosmetic outcome of patients after thyroidectomy. This study aimed to examine the reliability and validity of SAQCO. METHODS: We analyzed the cosmetic outcomes of 368 patients who underwent thyroidectomy and completed the SAQCO 1 year after surgery. The one-dimensionality, reliability, and validity of SAQCO were assessed using factor analysis models, Cronbach's alpha, and test-retest statistics. The differences in cosmesis indices between patient characteristics and surgical parameters were analyzed through comparative and regression analyses. RESULTS: The unidimensional convergence of SAQCO was examined. A Cronbach's alpha of 0.91, strong item-total correlation values (from 0.77 to 0.89), and a test-retest correlation value of 0.86 indicated the internal consistency and reliability of the SAQCO. The cosmesis index was significantly highest in the transoral (92.3 points) and transaxillary groups (90.9 points), followed by the postauricular (84.8 points) and transcervical groups (76.4 points). CONCLUSION: This study examined the reliability and validity of the SAQCO and showed that it is a suitable questionnaire for assessing cosmetic satisfaction of patients after thyroidectomy. The transoral and transaxillary approaches yield significantly superior cosmetic results compared to the conventional transcervical and postauricular approaches.
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Autoevaluación (Psicología) , Tiroidectomía , Humanos , Tiroidectomía/métodos , Estudios Transversales , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , PsicometríaRESUMEN
This study focuses on the development of a piezoelectric device capable of generating feedback vibrations to the user who manipulates it. The objective here is to explore the possibility of developing a haptic system that can replace physical buttons on the tactile screen of in-car systems. The interaction between the user and the developed device allows completing the feedback loop, where the user's action generates an input signal that is translated and outputted by the device, and then detected and interpreted by the user's haptic sensors and brain. An FEM (finite element model) via ANSYS multiphysics software was implemented to optimize the haptic performance of the wafer structure consisting of a BaTiO3 multilayered piezocomposite coated on a PET transparent flexible substrate. Several parameters relating to the geometric and mechanical properties of the wafer, together with those of the electrodes, are demonstrated to have significant impact on the actuation ability of the haptic device. To achieve the desired vibration effect on the human skin, the haptic system must be able to drive displacement beyond the detection threshold (~2 µm) at a frequency range of 100-700 Hz. The most optimized actuation ability is obtained when the ratio of the dimension (radius and thickness) between the piezoelectric coating and the substrate layer is equal to ~0.6. Regarding the simulation results, it is revealed that the presence of the conductive electrodes provokes a decrease in the displacement by approximately 25-30%, as the wafer structure becomes stiffer. To ensure the minimum displacement generated by the haptic device above 2 µm, the piezoelectric coating is screen-printed by two stacked layers, electrically connected in parallel. This architecture is expected to boost the displacement amplitude under the same electric field (denoted E) subjected to the single-layered coating. Accordingly, multilayered design seems to be a good alternative to enhance the haptic performance while keeping moderate values of E so as to prevent any undesired electrical breakdown of the coating. Practical characterizations confirmed that E=20 V/µm is sufficient to generate feedback vibrations (under a maximum input load of 5 N) perceived by the fingertip. This result confirms the reliability of the proposed haptic device, despite discrepancies between the predicted theory and the real measurements. Lastly, a demonstrator comprising piezoelectric buttons together with electronic command and conditioning circuits are successfully developed, offering an efficient way to create multiple sensations for the user. On the basis of empirical data acquired from several trials conducted on 20 subjects, statistical analyses together with relevant numerical indicators were implemented to better assess the performance of the developed haptic device.
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In this work, we developed a thin membrane of boehmite-polyvinyl alcohol composite (BOPOM) (diameter â¼ 5 cm) grafted ZIF-67 combing sol-gel and in-situ growth methods. The fabricated materials were characterized using FT-IR, SEM, XRD, TGA, XPS, and N2 sorption techniques. Results indicate that ZIF-67 nanocrystals were well-grafted into the AlOOH-PVA matrix with reduced crystallite size. Furthermore, the decorated ZIF-67 offered additional porous structures and adsorption sites onto the membrane, enhancing their removal efficiency towards Cr6+ compared to the undecorated and pristine ZIF-67. At pH â¼5.5, the harvested ZIF-67/BOPOM exhibited the highest Cr6+ uptake capacity of â¼56.4 mg g-1. Kinetic studies showed that the chromium adsorption on the prepared materials obeyed the pseudo-second-order model, and the kinetic parameters followed the order ZIFF-67/BOPOM (0.020 mg g-1 min-1) > BOPOM (0.011 mg g-1 min-1) > ZIF-67 (0.006 mg g-1 min-1). Notably, the adsorption mechanism study revealed that adsorbed Cr6+ was reduced to Cr3+, and the reduction yield was boosted owing to grafting ZIF-67 into the BOPOM. In addition, the fabricated ZIF-67/BOPOM can simultaneously remove Cr6+ and methyl orange dye (MO) in the solution due to their synergetic effects on each other. Furthermore, the hybrid membrane ZIF-67/BOPOM showed a chromium removal efficiency of â¼78.2% after four successive adsorption-desorption cycles. This study indicates that grafting nanocrystals ZIF-67 onto the super-platform boehmite-PVA is a promising strategy to harvest an adsorbent with a high adsorption ability, cost-effectiveness, and reduced secondary pollution risks.
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Cromo , Contaminantes Químicos del Agua , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Cromo/química , Agua , Adsorción , Contaminantes Químicos del Agua/química , Concentración de Iones de HidrógenoRESUMEN
BACKGROUND: The prevalence of functional disabilities, including difficulties in performing activities of daily living (ADLs) and instrumental activities of daily living (IADLs), increased significantly in recent years and burdened the healthcare system. METHODS: We analysed data from Korean Longitudinal Study of Aging (KLOSA) surveys, including participants aged 65 or older at baseline (2008), and participated in all 4-year follow-up periods in 2012, 2016, and 2020. A 4-year follow-up cohort study was applied to specify the change in functional disability and its trend over time among older adults. The generalized estimation equation (GEE) model was used to verify the uptrend of functional disability. Logistic regression analyses were applied to examine the influence of demographic and health parameters on the change in functional disability. RESULTS: The prevalence of ADL disability was 2.24% at baseline, increased to 3.10% after four years, 6.42% after eight years, and reached 11.12% after 12 years, five times higher than that at baseline. For IADL disability, they were 10.67%, 10.61%, 18.18%, and 25.57%, respectively. The uptrend of ADL disability in persons aged 65-74 (1.77% at baseline, increased to 7.65% in 2020, 12-year change of 5.88%) was slower than in those aged 75 or older (4.22% at baseline, increased to 25.90% in 2020, 12-year change of 21.68%). IADL disability were consistent with this. The high ADL/IADL disability rate was also present among persons with poor health status, physical inactivity, depression, dementia, and multiple chronic diseases. The relative risk of ADL/IADL disability in persons with a history of functional disability was significantly higher than in those without historical disabilities. CONCLUSION: The study verified the change in functional disability and its upward trend over time by older adults' demographic and health parameters. Functional disability was relatively flat tending to increase slowly during the early years but increased rapidly in the following years. Factors that strongly influenced the change in prevalence and the uptrend of functional disability were advanced age, living alone, being underweight or obese, poor health status, physical inactivity, depression, dementia, having multiple chronic diseases, and especially having a historical disability.
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Demencia , Personas con Discapacidad , Humanos , Anciano , Estudios de Seguimiento , Actividades Cotidianas , Estudios Longitudinales , Enfermedad Crónica , Demencia/diagnóstico , Demencia/epidemiología , República de Corea/epidemiología , Evaluación de la DiscapacidadRESUMEN
We investigated the hydrogen gas sensors based on AlGaN/GaN high electron mobility transistors (HEMTs) for high temperature sensing operation. The gate area of the sensor was functionalized using a 10 nm Pd catalyst layer for hydrogen gas sensing. A thin WO3 layer was deposited on top of the Pd layer to enhance the sensor selectivity toward hydrogen gas. At 200 °C, the sensor exhibited high sensitivity of 658% toward 4%-H2, while exhibiting only a little interaction with NO2, CH4, CO2, NH3, and H2S. From 150 °C to 250 °C, the 10 ppm hydrogen response of the sensor was at least eight times larger than other target gases. These results showed that this sensor is suitable for H2 detection in a complex gas environment at a high temperature.
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In this work, Ta-doped ZnO (Ta-ZnO) nanomaterials were synthesized by the hydrothermal method at different temperatures (110, 150, and 170 °C) for the photodegradation of methylene blue (MB) under visible light. Ta doping significantly affects the crystal defects, optical properties, and MB photocatalytic efficiency of ZnO materials. The optical absorption edge of Ta-ZnO 150 was redshifted compared to undoped ZnO, correlating to bandgap narrowing (E gTa-ZnO = 2.92 eV; E gZnO = 3.07 eV), implying that Ta doped ZnO is capable of absorbing visible light. Besides, Ta-doping was the reason for enhanced blue light emission in the photoluminescence spectrum, which is related to the oxygen defect V 0 O. It is also observed in the XPS spectra, where the percentage of oxygen in the oxygen-deficient regions (O531.5 eV) of Ta-ZnO150 is higher than that of ZnO150. It is an important factor in enhancing ZnO's photocatalytic efficiency. The MB degradation efficiency of Ta-doped ZnO reached the highest for Ta-ZnO 150 and was 2.5 times higher than ZnO under a halogen lamp (HL). Notably, the influence of hydrothermal temperature on the structural, morphological, and photoelectrochemical properties was discussed in detail. As a result, the optimal hydrothermal temperature for synthesizing the nanorod is 150 °C. Furthermore, photocatalytic experiments were also performed under simulated sunlight and natural sunlight. The nature of the photo-oxidative degradation of MB was also investigated.
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This paper reports a novel monitoring technique of bearings' bidirectional load (axial and radial) based on a smart sensor coating, which is screen printed onto the surface of a cross-shaped steel substrate. To ensure the accuracy and stability of measurement as well as the durability of the printed coating, the developed prototype is built according to design rules commonly used in electronic circuits. The finite element model (FEM) is used to predict the mechanical property of the tested substrate under either unidirectional or bidirectional loads. Regarding the output voltage of the piezoelectric sensor, experimental results are revealed to be well-corelated to the numerical simulation. It is pointed out that the output signal generated from the sensor (electrode) could be particularly affected due to the capacitive parasite coming from the conductive tracks (CTs). Such a phenomenon might be reduced by printing them on the dielectric layer rather than on the piezocomposite layer. The study also investigates a highly anisotropic shape of electrodes (rectangular instead of circle), indicating that the orientation of such electrodes (axial or radial) does affect the output measurement. To sum up, the high performance of a sensor network coating depends not only on the ultimate characteristics of its own materials, but also on its structural design. Such an issue has been rarely reported on in the literature, but is nonetheless crucial to achieving reliable condition monitoring of bearings, especially for multidirectional loads-a key signature of early failure detection.
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Objective: This paper assesses the relationship between demographics, health parameters, and functional limitations among older adults in Korea, including limitations in activities of daily living (ADLs) and instrumental activities of daily living (IADLs). Methods: We analyzed data from the Korean Longitudinal Study of Aging survey in 2020 and included only participants aged 65 and older. Multinomial logistic regression models were conducted to evaluate the factors that predicted functional limitations. Results: The prevalence of at least one ADL and IADL limitations were 6.14% (severe 1.94% and moderate 4.20%) and 15.49% (severe 3.11% and moderate 12.38%), respectively. People aged 85 and older had high rates of severe disability with 7.37% for ADLs and 12.06% for IADLs. High rates also occurred among people with low education, underweight, physical inactivity, depression, and three or more chronic diseases. Conclusion: Factors associated with functional limitations were age, educational status, body mass index, physical activity, depression, and chronic diseases. To prevent and improve functional limitations in the older populations, active and applicable interventions should be considered for modifiable factors such as physical activity, depression, and abnormal weight.
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Actividades Cotidianas , Humanos , Anciano , Estudios Transversales , Estudios Longitudinales , Enfermedad Crónica , República de Corea/epidemiologíaRESUMEN
Suction cups (SCs) are used extensively by the industrial sector, particularly for a wide variety of automated material-handling applications. To enhance productivity and reduce maintenance costs, an online supervision system is essential to check the status of SCs. This paper thus proposes an innovative method for condition monitoring of SCs coated with printed electronics whose electrical resistance is supposed to be correlated with the mechanical strain. A simulation model is first examined to observe the deformation of SCs under vacuum compression, which is needed for the development of sensor coating thanks to the 3D printing process. The proposed design involves three circle-shaped sensors, two for the top and bottom bellows (whose mechanical strains are revealed to be the most significant), and one for the lip (small strain, but important stress that might provoke wear and tear in the long term). For the sake of simplicity, practical measurement is performed on 2D samples coated with two different conductive inks subjected to unidirectional tensile loading. Graphical representations together with analytical models of both linear and nonlinear piezoresistive responses allows for the characterization of the inks' behavior under several conditions of displacement and speed inputs. After a comparison of the two inks, the most appropriate is selected as a consequence of its excellent adhesion and stretchability, which are essential criteria to meet the target field. Room temperature extrusion-based 3D printing is then investigated using a motorized 3D Hyrel printer with a syringe-extrusion modular system. Design optimization is finally carried out to enhance the surface detection of sensitive elements while minimizing the effect of electrodes. Although several issues still need to be further considered to match specifications imposed by our industrial partner, the achievement of this work is meaningful and could pave the way for a new generation of SCs integrated with smart sensing devices. The 3D printing of conductive ink directly on the cup's curving surface is a true challenge, which has been demonstrated, for the first time, to be technically feasible throughout the additive manufacturing (AM) process.
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In this study, gold nanoparticles (AuNPs) were synthesized via a green and environmentally-friendly approach and applied as a colorimetric probe for detecting Pb2+ ions in aqueous solution. Instead of toxic chemicals, Michelia tonkinensis (MT) seed extract was used for reducing Au3+ and stabilizing the formed AuNPs. The synthesis conditions, including temperature, reaction time, and Au3+ ion concentration, were optimized at 90 °C, 40 min, and 1.25 mM, respectively. The physicochemical properties of the produced MT-AuNPs were assessed by means of transmission electron microscopy, X-ray diffraction, field emission scanning electron microscopy, dynamic light scattering, and Fourier-transform infrared spectroscopy. The characterization results revealed that the MT-AuNPs exhibited a spherical shape with a size of about 15 nm capped by an organic layer. The colorimetric assay based on MT-AuNPs showed excellent sensitivity and selectivity toward Pb2+ ions with the limit of detection value of 0.03 µM and the limit of quantification of 0.09 µM in the linear range of 50-500 µM. The recoveries of inter-day and intra-day tests were 97.84-102.08% and 98.78-102.34%, respectively. The MT-AuNPs probe also demonstrated good and reproducible recoveries (98.71-101.01%) in analyzing Pb2+ in drinking water samples, indicating satisfactory practicability and operability of the proposed method.
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In this study, a simple, eco-friendly and low-cost approach was used to fabricate silver nanoparticles (AgNPs) from an aqueous extract of Gleditsia australis (GA) fruit. The nanoparticles synthesized in the optimal condition have an average size of 14 nm. The peroxidase-like activity of GA-AgNP in the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in combination with hydrogen peroxide (H2O2) was investigated. Further, optimal conditions for the use of peroxidase-like catalytic activity in sensing applications were identified. The colourimetric detection of H2O2 showed a linear range of 1-8 mM with a limit of detection (LOD) of 0.34 mM. The oxidation of TMB (red-TMB) enables the detection of glucose, which is converted into H2O2 and gluconic acid in the presence of the enzyme glucose oxidase. The observations showed linearity from 0.05 to 1.5 mM with a LOD of 0.038 mM. Moreover, the blue colour of oxidized TMB (ox-TMB) was reduced according to ascorbic acid (AA) concentration, with a linear range of 0.03-0.14 mM and a LOD of 3.0 µM. The practical use of the sensing system for the detection of AA was studied using real fruit juice and showed good sensitivity. Hence, the easy-to-use peroxidase-like sensor provides a new platform for the detection of bioactive compounds in biological systems.
Asunto(s)
Gleditsia , Nanopartículas del Metal , Ácido Ascórbico , Colorimetría , Frutas , Glucosa , Peróxido de Hidrógeno , Límite de Detección , Peroxidasa , PlataRESUMEN
Discovery of natural antioxidants has been carried out for decades relying mainly on experimental approaches that are commonly associated with time and cost demanding biochemical assays. The maturation of quantitative structure activity relationship (QSAR) modelling has provided an alternative approach for searching and designing antioxidant compounds with alleviated costs. As a contribution to this approach, this work aimed to establish a fragment-based 3D-QSAR procedure to discover and design potential antioxidants based on tryptophyllin L structures isolated from the red tree frog Litoria rubella. A force field and a Gaussian 3D-QSAR model were built to screen for potential antioxidants from tripeptide fragments covering all sequences of tryptophyllin L database. Among those, PWY(NH2 ) corresponding tryptophyllin L 4.1 was predicted to have the highest 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS+ ·) scavenging capability. Two newly designed peptides PYW and PYW(NH2 ) together with PWY(NH2 ), tryptophyllin L 4.1, and the reference peptide PWY were synthesized and subjected to two antioxidant assays including ABTS scavenging and ferric reducing antioxidant power assays. Although the experimental TEAC values of the five peptides were roughly similar to those from predictions, the activity order was not in agreement with the predictions. The dissimilarities were accounted by the difference in the experimental procedures, the deviation of modelling regression, and the synergetic effect of structural and experimental features. The ABTS radical scavenging assays revealed that all the tested peptides were strong ABTS+ · scavengers with the antioxidant capabilities approximately twice as high as trolox and higher than glutathione. The ferric reducing activities of the peptides were, on the other hand, much weaker than that of trolox suggesting different antioxidant mechanisms inserted by trolox and the peptides. This work was a demonstration that 3D-QSAR methods can be employed in conjunction with experimental methods to effectively detect and design antioxidant peptides.