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Smooth muscle cells (SMCs) sense and respond to mechanical stimuli in their extracellular microenvironments (ECMs), playing a crucial role in muscle tissue engineering. Increasing evidence from topological cues-mediated mechanotransduction of SMCs in ECMs has suggested some potential underlying mechanisms of how SMC functions and maturation are regulated by their mechanosensing leading to transduction. However, how the expression of yes-associated protein 1 (YAP) influences the phenotypic shift from synthetic to contractile is still controversial. Here, pseudo-3D topological alignments mimicking native muscle tissues are generated using laser-cutter engraving to explore the influence of topological cues on SMC mechanotransduction and maturation. The analysis of topological cue-mediated mechanotransduction and maturation marker expression revealed YAP is involved in mechanotransduction for SMCs cultured on cross-patterned substrates in the presence of cell-cell interactions. Moreover, these SMCs with YAP-linked mechanosensing showed higher expression of calponin, indicating a shift toward contractile phenotypes in vitro and in vivo. Furthermore, it showed skeletal muscle cells has different mechanosensing and maturation mechanisms compared to SMCs, revealing muscle type-dependent different sensing of topological cues, and converting into maturation-associated signaling cascades. This study provides insights into the regulation of SMC mechanotransduction and maturation by topological cues, suggesting the involvement of YAP-linked signaling pathways in this process.
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PURPOSE: To investigate the risk of retinal vascular occlusion in patients with Moyamoya disease (MMD). DESIGN: Retrospective, longitudinal cohort study using the Korean National Health Insurance Service database. PARTICIPANTS: Newly diagnosed MMD patients (n=34,627), who were diagnosed between 2004 and 2022, and their propensity score matched controls (n=136,945) were included. METHODS: We identified retinal vascular occlusion events using diagnostic codes for central retinal artery occlusion, other retinal artery occlusion, and retinal vein occlusion. After a washout-period from 2002 to 2003, information on the diagnosis of retinal vascular occlusion was extracted in both MMD and control group during the follow up period. The association between MMD and the risk of subsequent retinal vascular occlusion was investigated using a time-dependent Cox proportional hazard model and Kaplan-Meier survival analysis with log-rank test adjusted for age, sex, and comorbidities. MAIN OUTCOME MEASURES: Hazard ratios (HRs) and 95% confidence intervals (CIs) for retinal vascular occlusion development according to the MMD. RESULTS: MMD was associated with an increased risk of subsequent retinal vascular occlusion even after adjusting for confounding variables (HR, 1.22; 95% CI, 1.09-1.36). Among the subtypes of retinal vascular occlusion, central retinal artery occlusion showed a highest HR (2.23; 95% CI, 1.35-3.7). Incidence probability of retinal vascular occlusion was significantly higher among MMD patients than controls (P < 0.001, log-rank test). CONCLUSION: In this nationwide population-based cohort study, patients with MMD in Korea had an elevated risk of retinal vascular occlusion, suggesting that the MMD is one of the risk factors for retinal vascular occlusion.
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The potential of hybrid perovskite/organic solar cells (HSCs) is increasingly recognized owing to their advantageous characteristics, including straightforward fabrication, broad-spectrum photon absorption, and minimal open-circuit voltage (VOC) loss. Nonetheless, a key bottleneck for efficiency improvement is the energy level mismatch at the perovskite/bulk-heterojunction (BHJ) interface, leading to charge accumulation. In this study, it is demonstrated that introducing a uniform sub-nanometer dipole layer formed of B3PyMPM onto the perovskite surface effectively reduces the 0.24 eV energy band offset between the perovskite and the donor of BHJ. This strategic modification suppresses the charge recombination loss, resulting in a noticeable 30 mV increase in the VOC and a balanced carrier transport, accompanied by a 5.0% increase in the fill factor. Consequently, HSCs that achieve power conversion efficiency of 24.0% is developed, a new record for Pb-based HSCs with a remarkable increase in the short-circuit current of 4.9 mA cm-2, attributed to enhanced near-infrared photon harvesting.
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Background: FIR therapy is used in various medical settings to treat diseases associated with inflammation and edema. Unlike conventional FIR lamp therapy, this study investigated how body fluids change depending on the intensity and duration of FIR irradiation to the whole body. Method: Subjects in group A (n = 27) were exposed to FIR emitted from a loess bio-ball mat set at 40 °C for 30 min, and subjects in group B (n = 27) were exposed to FIR emitted from a loess bio-ball mat set at 30 °C for 7 h during sleep. Changes in bioimpedance parameters and fluid-related values were measured using a body fluid analyzer before and after exposure to FIR. Results: Changes in bioimpedance parameters associated with inflammatory fluids were quantitatively confirmed. In group A, there was a minimal change in fluid-related measurements. However, significant changes in bioimpedance parameters associated with inflammatory fluids were observed in group B exposure to FIR for 7 h during sleep. Conclusions: FIR emitted from loess bio-balls activates biological tissues and lymphatic circulation, gradually reducing the levels of inflammatory fluids over time.
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Pentraxin 3 (PTX3) is a prototypic humoral soluble pattern-recognition molecule known to function in immunity-related inflammation. Given the lack of information on the precise functions of PTX3 in the pathogenesis of Graves' orbitopathy (GO), this study investigated the role of PTX3 in the inflammation and adipogenesis mechanisms of GO. We first compared the PTX3 expression between orbital tissues from patients with GO and normal controls using real-time PCR, which estimated significantly higher PTX3 transcript levels in the GO tissues than in the normal tissues. In addition, PTX3 production was markedly increased upon interleukin (IL)-1ß and adipogenic stimulation. We then evaluated the effects of silencing PTX3 in primary orbital fibroblast cultures by analyzing the expression levels of pro-inflammatory cytokines, adipogenesis-related proteins, and downstream transcription factors in cells transfected with or without small interfering RNA against PTX3, using western blot. Silencing PTX3 attenuated the IL-1ß-induced secretion of pro-inflammatory cytokines, including IL-6, IL-8, monocyte chemotactic protein-1, intercellular adhesion molecule-1, and cyclooxygenase-2, and suppressed the IL-1ß-mediated activation of p38 kinase, nuclear factor-κB, and extracellular signal-regulated kinase. Moreover, PTX3 knockdown suppressed adipogenic differentiation, as assessed using Oil Red O staining, as well as the expression of adipogenesis-associated transcription factors including peroxisome proliferator-activated receptor-γ, CCAAT/enhancer-binding proteins α and ß, adipocyte protein 2, adiponectin, and leptin. Thus, this study suggests that PTX3 plays a significant role in the pathogenesis of GO and may serve as a novel therapeutic target for the condition.
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Adipogenia , Proteína C-Reativa , Oftalmopatia de Graves , Inflamação , Componente Amiloide P Sérico , Humanos , Componente Amiloide P Sérico/genética , Componente Amiloide P Sérico/metabolismo , Oftalmopatia de Graves/metabolismo , Oftalmopatia de Graves/genética , Oftalmopatia de Graves/patologia , Adipogenia/genética , Proteína C-Reativa/metabolismo , Proteína C-Reativa/genética , Inflamação/metabolismo , Inflamação/patologia , Inflamação/genética , Citocinas/metabolismo , Masculino , Feminino , Interleucina-1beta/metabolismo , Pessoa de Meia-Idade , Fibroblastos/metabolismo , Adulto , Mediadores da Inflamação/metabolismo , Células Cultivadas , Transdução de SinaisRESUMO
As atomic-scale etching and deposition processes become necessary for manufacturing logic and memory devices at the sub-5 nm node, the limitations of conventional plasma technology are becoming evident. For atomic-scale processes, precise critical dimension control at the sub-1 nm scale without plasma-induced damage and high selectivity between layers are required. In this paper, a plasma with very low electron temperature is applied for damage-free processing on the atomic scale. In plasmas with an ultralow electron temperature (ULET, Te < 0.5 eV), ion energies are very low, and the ion energy distribution is narrow. The absence of physical damage in ULET plasma is verified by exposing 2D structural material. In the ULET plasma, charging damage and radiation damage are also expected to be suppressed due to the extremely low Te. This ULET plasma source overcomes the limitations of conventional plasma sources and provides insights to achieve damage-free atomic-scale processes.
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Biologically inspired artificial vision research has led to innovative robotic vision systems with low optical aberration, wide field of view, and compact form factor. However, challenges persist in object detection and recognition against complex backgrounds and varied lighting. Inspired by the feline eye, which features a vertically elongated pupil and tapetum lucidum, this study introduces an artificial vision system designed for superior object detection and recognition in a monocular framework. Using a slit-like elliptical aperture and a patterned metal reflector beneath a hemispherical silicon photodiode array, the system reduces excessive light and enhances photosensitivity. This design achieves clear focus under bright light and enhanced sensitivity in dim conditions. Theoretical and experimental analyses demonstrate the system's ability to filter redundant information and detect camouflaged objects in diverse lighting, representing a substantial advancement in monocular camera technology and the potential of biomimicry in optical innovations.
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PURPOSE: To investigate the significance of intravitreal anti-vascular endothelial growth factor treatment in patients with neovascular age-related macular degeneration and poor visual acuity. METHODS: Retrospective study of patients with neovascular age-related macular degeneration with baseline best-corrected visual acuity of ≤20/200. Patients were divided into regular treatment and scarce treatment groups according to whether they underwent consecutive intravitreal anti-vascular endothelial growth factor treatments at intervals of ≤4 months or not. RESULTS: A total of 131 eyes were included: 87 and 44 eyes in the regular treatment and scarce treatment groups, respectively. The regular treatment group showed significantly improved preservation of lesion size at both Years 1 and 2, with significantly fewer incidences of new subretinal hemorrhage. Improvements in visual acuity, reduction in central subfield macular thickness, and maximal height of choroidal neovascularization were significantly favorable in the regular treatment group at Year 1, and central subfield macular thickness was significantly decreased at Year 2. Survival analysis revealed that the regular treatment group had significantly greater preservation of visual acuity and lesion size than that in the scarce treatment group. CONCLUSION: Maintaining intravitreal anti-vascular endothelial growth factor treatment for patients with neovascular age-related macular degeneration and poor vision showed significant advantages in visual acuity and lesion size stability and reduced the incidence of new subretinal hemorrhage, which suggests preservation of paracentral vision.
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Inibidores da Angiogênese , Bevacizumab , Injeções Intravítreas , Ranibizumab , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular , Acuidade Visual , Degeneração Macular Exsudativa , Humanos , Acuidade Visual/fisiologia , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/uso terapêutico , Estudos Retrospectivos , Masculino , Feminino , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Idoso , Degeneração Macular Exsudativa/tratamento farmacológico , Degeneração Macular Exsudativa/fisiopatologia , Degeneração Macular Exsudativa/diagnóstico , Ranibizumab/administração & dosagem , Idoso de 80 Anos ou mais , Bevacizumab/administração & dosagem , Bevacizumab/uso terapêutico , Angiofluoresceinografia , SeguimentosRESUMO
PURPOSE: To determine the association between pentosan polysulfate (PPS) use and the subsequent development of maculopathy in an Asian population. DESIGN: A nationwide, population-based retrospective cohort study using the Health Insurance Review and Assessment Service database. PARTICIPANTS: A total of 103 553 individuals in the PPS user group and 205 792 individuals in the PPS nonuser group, all newly diagnosed with cystitis between 2009 and 2020. METHODS: The association between PPS use and maculopathy was evaluated using a time-dependent Cox proportional hazard model. Additionally, 2 sensitivity analyses were conducted by defining PPS users as individuals with an observation period over 6 months from the initial prescription or those with a cumulative dose exceeding 9 g, using the same analysis. MAIN OUTCOME MEASURES: The outcome measures included the hazard ratios (HRs) representing the association between PPS use and maculopathy. RESULTS: Use of PPS was associated with an increased risk of subsequent maculopathy in univariate (HR, 1.7; 95% confidence interval [CI], 1.66-1.75) and multivariate analysis (HR, 1.34; 95% CI, 1.31-1.38). These results were also confirmed in 2 sensitivity analyses. The mean cumulative dose of PPS for the cohort was 37.2 ± 76.7 g. CONCLUSIONS: In this nationwide cohort study involving an Asian population, individuals with cystitis using PPS exhibit an increased risk of developing subsequent maculopathy. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
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PURPOSE: To compare the effects of additional multimodal shoulder injections on postoperative rebound pain in patients undergoing arthroscopic rotator cuff repair (ASRCR) under interscalene brachial plexus block (ISBPB) anesthesia. METHODS: A single-blind randomized controlled trial was conducted with 67 patients between April and December 2023. Patients undergoing ASRCR who received ISBPB anesthesia, rather than general anesthesia, with a minimum follow-up period of 48 hours were included. The injection group received 40 mL of 0.75% ropivacaine, 20 mg morphine, 1:200,000 epinephrine, and saline solution, totaling 100 mL. After surgery, the injection was administered to the subacromial space (50 mL) with blind suprascapular nerve block (25 mL) and blind axillary nerve block (25 mL). Control subjects received 100 mL of saline solution. Intravenous patient-controlled analgesia (IV-PCA) was used as adjuvant analgesia for all patients. The primary outcome was evaluated using the visual analog scale (VAS) pain score at 12 hours after surgery, with secondary outcomes of the incidence of rebound pain and VAS pain scores at 0, 2, 4, 8, 24, 36, and 48 hours postoperatively. Fentanyl in the IV-PCA and rescue analgesic amounts, complications, and patient satisfaction were recorded. RESULTS: Sixty-seven patients (32 in the injection group, 35 in the control group) with a mean age of 61.1 ± 9.0 years were included. The primary outcome assessment, VAS pain score at 12 hours, significantly favored the injection group (2.7 ± 0.93 vs 4.1 ± 1.70, P < .001). The incidence of rebound pain was 18.8% and 65.7% in the injection and control groups, respectively (18.8% vs 65.7%, P < .001). The injection group reported better VAS pain scores at 24, 36, and 48 hours and lower fentanyl use over the 48-hour postoperative period (P = .014). The use of rescue analgesics was similar between groups, and no complications were associated with multimodal shoulder injections. Satisfaction levels were similar in both groups. CONCLUSIONS: The present study found that patients who underwent multimodal shoulder injections during ASRCR under ISBPB anesthesia had significantly lower VAS pain scores at 12 hours postoperatively and reduced incidence of rebound pain compared with the control group. Pain levels were consistently lower from 12 to 48 hours postoperatively. Additionally, the injection group had reduced opioid consumption within the first 48 hours postoperatively, with no complications observed. LEVEL OF EVIDENCE: Level I, randomized controlled trial.
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The number of individuals with underlying medical conditions has been increasing steadily. These individuals are relatively vulnerable to harmful external factors. But it has not been proven that the effects of hazardous chemicals may differ depending on their physicochemical properties. This study determines the toxic effects of two chemicals with high indoor exposure risk and different physicochemical properties on an underlying disease model. A pulmonary arterial hypertension (PAH) model was constructed by a single subcutaneous injection of monocrotaline (MCT; 60â¯mg/kg) into Sprague-Dawley rats. After three weeks, formaldehyde (FA; 2.5â¯mg/kg) and polyhexamethylene guanidine (PHMG; 0.05â¯mg/kg) were administered once via intratracheal instillation, and rats were necropsied one week later. Exposure to FA and PHMG affected organ weight and the Fulton and toxicity indices in rats induced with PAH. FA promoted bronchial injury and aggravated PAH, while PHMG only induced alveolar injury. Additionally, the differentially expressed genes were altered following exposure to FA and PHMG, as were the associated diseases (cardiovascular disease and pulmonary fibrosis, respectively). In conclusion, inhaled chemicals with different physicochemical properties can cause damage to organs, such as the lungs and heart, and can aggravate underlying diseases. This study elucidates indoor inhaled exposure-induced toxicities and alerts patients with pre-existing diseases to the harmful chemicals.
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Modelos Animais de Doenças , Formaldeído , Lesão Pulmonar , Ratos Sprague-Dawley , Animais , Ratos , Masculino , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/patologia , Formaldeído/toxicidade , Guanidinas/toxicidade , Monocrotalina/toxicidade , Exposição por Inalação , Pulmão/efeitos dos fármacos , Pulmão/patologia , Hipertensão Arterial Pulmonar/induzido quimicamente , Substâncias Perigosas/toxicidadeRESUMO
Introduction: Cigarette smoke (CS) exacerbates the severity of diseases not only in lungs, but also in systemic organs having no direct contact with smoke. In addition, smoking during pregnancy can have severe health consequences for both the mother and the fetus. Therefore, our aim was to evaluate effects of prenatal exposure to CS on acetaminophen (APAP)-induced acute liver injury (ALI) in offspring. Methods: Female C57BL/6 mice on day 6 of gestation were exposed to mainstream CS (MSCS) at 0, 150, 300, or 600 µg/L for 2 h a day, 5 days a week for 2 weeks using a nose-only exposure system. At four weeks old, male offspring mice were injected intraperitoneally with a single dose of APAP at 300 mg/kg body weight to induce ALI. Results: Maternal MSCS exposure significantly amplified pathological effects associated with ALI as evidenced by elevated serum alanine aminotransferase levels, increased hepatocellular apoptosis, higher oxidative stress, and increased inflammation. Interestingly, maternal MSCS exposure reduced microRNA (miR)-34a-5p expression in livers of offspring. Moreover, treatment with a miR-34a-5p mimic significantly mitigated the severity of APAP-induced hepatotoxicity. Overexpression of miR-34a-5p completely abrogated adverse effects of maternal MSCS exposure in offspring with ALI. Mechanistically, miR-34a-5p significantly decreased expression levels of hepatocyte nuclear factor 4 alpha, leading to down-regulated expression of cytochrome P450 (CYP)1A2 and CYP3A11. Discussion: Prenatal exposure to MSCS can alter the expression of miRNAs, even in the absence of additional MSCS exposure, potentially increasing susceptibility to APAP exposure in male offspring mice.
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Muscle atrophy is known to be one of the symptoms leading to sarcopenia, which significantly impacts the quality of life, mortality, and morbidity. Therefore, the development of therapeutics for muscle atrophy is essential. This study focuses on addressing muscle loss and atrophy using Ulmus macrocarpa extract and its marker compound, catechin 7-O-ß-D-apiofuranoside, by investigating their effects on biomarkers associated with muscle cell apoptosis. Additionally, protein and gene expression in a muscle atrophy model were examined using Western blotting and RT-PCR. Ulmus macrocarpa has been used as food or medicine due to its safety, including its roots, barks, and fruit. Catechin 7-O-ß-D apiofuranoside is an indicator substance of plants of the Ulmus genus and has been reported to have various effects such as antioxidant and anti-inflammatory effects. The experimental results demonstrated that catechin glycoside and Ulmus macrocarpa extract decreased the expression of the muscle-degradation-related proteins Atrogin-1 and Muscle RING-Finger protein-1 (MuRF1) while increasing the expression of the muscle-synthesis-related proteins Myoblast determination (MyoD) and Myogenin. Gene expression confirmation experiments validated a decrease in the expression of Atrogin and MuRF1 mRNA and an increase in the expression of MyoD and Myogenin mRNA. Furthermore, an examination of muscle protein expression associated with the protein kinase B (Akt)/forkhead box O (FoxO) signaling pathway confirmed a decrease in the expression of FoxO, a regulator of muscle protein degradation. These results confirm the potential of Ulmus macrocarpa extract to inhibit muscle apoptosis, prevent muscle decomposition, and promote the development of functional materials for muscle synthesis, health-functional foods, and natural-product-derived medicines.
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With the increasing demand for high-performance leisure boat propellers, this study explores the development of high-strength aluminum alloy propellers using the low-pressure die-casting (LPDC) process. In Part I of the study, we identified the optimal alloy compositions for Al-6Zn-2Mg-1.5Cu propellers and highlighted the challenges of hot tearing at the junction between the hub and blades. In this continuation, we developed a coupled thermal fluid stress analysis model using ProCAST software to optimize the LPDC process. By adjusting casting parameters such as the melt supply temperature, initial mold temperature, and curvature radius between the hub and blades, we minimized hot tearing and other casting defects. The results were validated through simulations and practical applications, showing significant improvements in the quality and structural integrity of the propellers. Non-destructive testing using X-ray CT confirmed the reduction in internal defects, demonstrating the effectiveness of the simulation-based approach for alloy design and process optimization.
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PURPOSE: A tibial cement spacer (TCS) with spikes offers better initial stability than a conventional TCS and reduces spacer-related problems in two-stage revision total knee arthroplasty (R-TKA) for infection. We compared the clinical outcomes of two-stage revision arthroplasty for infected TKA using spiked TCS with that of conventional TCS. METHODS: This retrospective cohort study included 29 patients who underwent two-stage revision arthroplasty using an articulating cement spacer and who could be followed up for at least one year. Group S comprised 14 patients using spiked TCS, whereas Group C comprised 15 patients using conventional TCS. Demographic data, the interval from first to second stage revision, motion arc, numerical rating scale (NRS), Knee Society (KS) score, serum levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and frequency of repeating the first-stage and infection recurrence after R-TKA between the groups were analyzed. RESULTS: No significant differences were observed in the female ratio and mean age between both groups. The mean interval between the first and second stage revision was significantly shorter in Group S than in Group C. The mean motion arc was significantly larger in Group S than in Group C. The mean NRS was significantly lower in Group S than in Group C. The mean KS score in Group S was significantly higher than that in Group C. Serum ESR and CRP levels did not differ between the groups. The frequency of repeating the first stage was lower in Group S than in Group C. However, the recurrence rate after R-TKA was higher in Group S than in Group C. CONCLUSION: Compared with conventional TCS, spiked TCS shortened the period until R-TKA and improved pain and function levels. However, no significant difference existed in the rate of infection recurrence after R-TKA.
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Artroplastia do Joelho , Cimentos Ósseos , Prótese do Joelho , Infecções Relacionadas à Prótese , Reoperação , Humanos , Feminino , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Masculino , Reoperação/métodos , Estudos Retrospectivos , Idoso , Infecções Relacionadas à Prótese/cirurgia , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/etiologia , Pessoa de Meia-Idade , Resultado do Tratamento , Prótese do Joelho/efeitos adversos , Amplitude de Movimento Articular/fisiologia , Articulação do Joelho/cirurgia , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , Tíbia/cirurgia , Sedimentação SanguíneaRESUMO
BACKGROUND: The prevalence of diabetes is increasing globally, highlighting the importance of preventive healthcare. This study aimed to identify the diabetic retinopathy (DR) screening rates and risk factors linked to DR screening nonadherence in the Korean population through a nationally representative sample survey. METHODS: Among the Korea National Health and Nutrition Examination Survey database from 2016 to 2021, participants aged ≥ 40 years with diabetes were included. The weighted estimate for nonadherence to DR screening within a year was calculated. Risk factor analyses were conducted using univariate and multivariate logistic regression. RESULTS: Among the 3,717 participants, 1,109 (29.5%) underwent DR screening within the past year, and this national estimate exhibited no statistically significant difference from 2016 to 2021 (P = 0.809). Nonadherence to annual DR screening was associated with residing in rural areas, age ≥ 80 years, low educational level, self-reported good health, absence of ocular disease, current smoking, lack of exercise and dietary diabetes treatment, and no activity limitation (all P < 0.05). CONCLUSION: The recent DR screening rate in Korea was relatively low. Factors associated with apathy and complacency towards personal health were associated with the nonadherence to DR screening. Educational interventions have the potential to enhance the annual screening rate for diabetic patients.
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Retinopatia Diabética , Programas de Rastreamento , Inquéritos Nutricionais , Humanos , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , República da Coreia/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Adulto , Fatores de Risco , Idoso de 80 Anos ou mais , Modelos Logísticos , Prevalência , Razão de ChancesRESUMO
Recent advances in the leisure boat industry have spurred demand for improved materials for propeller manufacturing, particularly high-strength aluminum alloys. While traditional Al-Si alloys like A356 are commonly used due to their excellent castability, they have limited mechanical properties. In contrast, 7xxx series alloys (Al-Zn-Mg-Cu based) offer superior mechanical characteristics but present significant casting challenges, including hot-tearing susceptibility (HTS). This study investigates the optimization of 7xxx series aluminum alloys for low-pressure die-casting (LPDC) processes to enhance propeller performance and durability. Using a constrained rod-casting (CRC) method and finite element simulations, we evaluated the HTS of various alloy compositions. The results indicate that increasing Zn and Cu contents generally increase HTS, while a sufficient Mg content of 2 wt.% mitigates this effect. Two optimized quaternary Al-Zn-Mg-Cu alloys with relatively low HTS were selected for LPDC propeller production. Simulation and experimental results demonstrated the effectiveness of the proposed alloy compositions, highlighting the need for further process optimization to prevent hot tearing in high Mg and Cu content alloys.
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Objectives: Childhood maltreatment can negatively impact cognitive development, including executive function, working memory, and processing speed. This study investigated the impact of childhood maltreatment on cognitive function in young adults using various measurements, including computerized tests, and their relationship with emotional dysregulation. Methods: We recruited 149 healthy individuals with and without maltreatment experiences and used the Wechsler Adult Intelligence Scale IV (WAIS-IV) and a computerized battery to analyze cognitive function. Results: Both the WAIS-IV and computerized tests revealed that individuals with a history of childhood maltreatment had decreased cognitive function, especially in terms of working memory and processing speed. These individuals tended to employ maladaptive emotion regulation strategies. Among cognitive functions, working memory is negatively related to maladaptive emotion regulation strategies such as catastrophizing. Conclusion: This study highlights the effects of childhood maltreatment on cognitive function in young adulthood. Moreover, the study suggests clinical implications of cognitive interventions for improving emotion regulation and cognitive function in individuals with a history of childhood maltreatment.