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PURPOSE: The efficacy of exercise in men with prostate cancer (PCa) on active surveillance (AS) remains unclear. In this meta-analysis, we aimed to examine the effects of exercise in PCa patients on AS. METHODS: A literature search was conducted in PubMed, EMBASE, and the Cochrane Library using search terms, including exercise, PCa, AS, and randomized controlled trials (RCTs). The means and standard deviations for peak oxygen consumption (VO2peak), prostate-specific antigen (PSA) levels, and quality of life (QoL) were extracted for the intervention and control groups. A random-effects model was used to summarize the effects of exercise. RESULTS: Of the 158 identified studies, six RCTs with 332 patients were included. The interventions included lifestyle modifications (aerobic exercise + diet) in three studies and different exercise modalities in three studies. The intervention duration was 2-12 months; three interventions were supervised and three were self-directed. The pooled weighted mean difference between exercise and usual care for VO2peak was 1.42 mL/kg/min (95% confidence interval [CI]: 0.30 to 2.54, P ≤ 0.001). A non-significant effect was observed for QoL (pooled standardized mean difference [SMD]: 0.24, 95% CI: - 0.03 to 0.51, P = 0.08) which became statistically significant and stronger after excluding one outlier study (P < 0.001). Exercise also had a positive effect on PSA levels (pooled SMD: - 0.43, 95% CI: - 0.87 to 0.01, P = 0.05). CONCLUSION: Exercise improves cardiorespiratory fitness and may improve QoL and PSA levels in men with PCa on AS. Further studies with larger sample sizes are warranted to obtain more reliable results.
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Antígeno Prostático Específico , Neoplasias da Próstata , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Masculino , Antígeno Prostático Específico/sangue , Consumo de Oxigênio/fisiologia , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Conduta Expectante/métodosRESUMO
Primary extraosseous intracranial Ewing sarcoma (ES) is an extremely rare disease, limited to the pediatric population, that primarily originates in the skull. Here, we present an unusual case of adult Ewing's sarcoma originating from the brain parenchyma. The 50-year-old male patient visited our hospital with severe headache lasting 3 weeks. MRI presented 6.1×6.2×5.2 cm sized heterogeneously enhanced mass containing peritumoral edema in the right frontal lobe. The patient underwent right frontal craniotomy, at which time the gray and red masses adhered to the surrounding brain parenchyma. The mass was completely resected using neuronavigation and electrophysiological monitoring. Histopathological examination revealed ES-compatible findings of small round cell tumor and CD-99 positive membranous immunostaining. Next generation sequencing revealed translocation and fusion of EWSR1 and FLI1, consistent with a confirmed diagnosis of ES. Consequently, the patient underwent postoperative radiotherapy. The present case revealed adult primary intracranial ES arising from the frontal lobe. Although its etiology remains poorly understood, intraparenchymal ES should be included in the differential diagnosis of parenchymal brain tumors.
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Physical unclonable functions (PUFs) have attracted interest in demonstrating authentication and cryptographic processes for Internet of Things (IoT) devices. We demonstrated four-dimensional PUFs (4D PUFs) to realize time-varying chaotic phosphorescent randomness on MoS2 atomic seeds. By forming hybrid states involving more than one emitter with distinct lifetimes in 4D PUFs, irregular lifetime distribution throughout patterns functions as a time-varying disorder that is impossible to replicate. Moreover, we established a bit extraction process incorporating multiple 64 bit-stream challenges and experimentally obtained physical features of 4D PUFs, producing countless random 896 bit-stream responses. Furthermore, the weak and strong PUF models were conceptualized and demonstrated based on 4D PUFs, exhibiting superior cryptological performances, including randomness, uniqueness, degree of freedom, and independent bit ratio. Finally, the data encryption and decryption in pictures were performed by a single 4D PUF. Therefore, 4D PUFs could enhance the counterfeiting deterrent of existing optical PUFs and be used as an anticounterfeiting security strategy for advanced authentication and cryptographic processes of IoT devices.
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BACKGROUND: Various physical activity (PA) guidelines recommend leisure PA and resistance exercise (RE). However, the impact of PA and RE on the prevalence of depressive symptoms remains unclear. We investigated whether meeting PA and RE guidelines is associated with the prevalence of depressive symptoms using nationally representative samples. METHODS: We analyzed data from 11,829 (5111 male and 6718 female) participants aged 19+ years in the Korean National Health and Nutrition Examination Survey (2016 and 2018). Those with doctor's diagnosis of depression or with a cut-off score of ≥11 on the Patient Health Questionnaire-9 were defined as having depressive symptoms. PA and RE were measured using a validated Global PA Questionnaire. Logistic regression analysis was used to examine the association between participating in leisure PA, simultaneously meeting RE guidelines, and experiencing depressive symptoms. RESULTS: Those who participated in leisure PA and met RE guidelines had a lower prevalence of depressive symptoms than those who did not (p for trend <0.001). After adjusting for covariates, those who participated in leisure PA and met RE guideline were significantly less likely to have depressive symptoms in male (OR = 0.52, 95 % CI 0.32-0.84) and female (OR = 0.71, 95 % CI 0.48-1.06), compared with those who did not participate in leisure PA but also did not meet RE guideline. LIMITATIONS: The cross-sectional nature of the data prevented causal claims. CONCLUSIONS: Participation in leisure PA and RE was associated with a lower prevalence of depressive symptoms. This suggests both leisure PA and RE should be encouraged as effective means for preventing depression.
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Depressão , Exercício Físico , Atividades de Lazer , Inquéritos Nutricionais , Treinamento Resistido , Humanos , Masculino , Feminino , República da Coreia/epidemiologia , Adulto , Pessoa de Meia-Idade , Prevalência , Depressão/epidemiologia , Treinamento Resistido/estatística & dados numéricos , Idoso , Estudos Transversais , Adulto JovemRESUMO
BACKGROUND: Chronic kidney disease (CKD) poses a significant health challenge, yet early detection remains difficult. Resting heart rate (RHR) has been shown to be a reliable indicator of type 2 diabetes, prompting interest in its potential as an independent predictor of CKD. This study aimed to investigate the association between RHR and CKD prevalence, as well as explore potential interactions between RHR and other risk factors for CKD in a sample of 25,246 adults. METHODS: Data from the Korean National Health and Nutrition Examination Survey (2011-2014) were utilized for this study, with 19,210 participants included after screening. Logistic regression analysis was employed to examine the relationship between RHR and CKD prevalence. Stratified analyses were conducted based on known risk factors for CKD. RESULTS: Participants with an RHR ≥ 90 bpm exhibited a 2.07-fold [95% confidence interval (CI): 1.28-3.34] and 2.22-fold (95% CI: 1.42-3.48) higher prevalence of CKD in men and women, respectively, compared to those with an RHR < 60 bpm. The association between RHR and CKD prevalence was particularly pronounced in younger participants (40-59 years vs. ≥ 60 years), individuals with diabetes (yes vs. no), and those with a longer duration of diabetes (≥ 7 years vs. < 7 years). CONCLUSION: Elevated RHR was found to be significantly associated with a higher prevalence of CKD in both men and women, independent of demographic, lifestyle, and medical factors. These findings suggest that RHR could serve as a valuable predictor for undiagnosed CKD.
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Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Adulto , Masculino , Humanos , Feminino , Diabetes Mellitus Tipo 2/epidemiologia , Inquéritos Nutricionais , Prevalência , Frequência Cardíaca/fisiologia , Fatores de Risco , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , República da Coreia/epidemiologiaRESUMO
PURPOSE: The purpose of this qualitative study was to use semi-structured interviews and thematic analysis to elicit key influencing factors (i.e., behavioral, normative, and control beliefs) related to physical activity and exercise in colorectal cancer survivors. METHODS: Colorectal cancer survivors (N = 17) were recruited from exercise programs designed for colorectal cancer survivors at the Yonsei Cancer Center, Seoul, South Korea. A purposive sampling method was used. Interview questions were informed by the theory of planned behavior (TPB). Semi-structured face-to-face interviews were conducted, and open-ended questions addressed the research question. Interviews were transcribed verbatim and analyzed using thematic analysis. RESULTS: Participants were on average 2.2 years post-treatment. The mean age of the sample was 55.9 years. Key behavioral, normative, and control beliefs emerged in the data. For behavioral beliefs, colorectal cancer survivors believed that exercise would result in physical and psychological improvements, and improve their bowel problems. For normative beliefs, most colorectal cancer survivors wanted their oncologists' approval for participation of exercise. Family members, more specifically the spouse, were also influencing factors for colorectal cancer survivors adopting physical activity. The most frequently mentioned control belief was that supervised exercise with an exercise specialist made exercise participation easier. CONCLUSIONS AND IMPLICATIONS: Beliefs identified in this study can inform TPB-based physical activity interventions tailored for colorectal cancer survivors. While information alone may not lead to behavior change, integrating these beliefs with other influential factors can potentially enhance intervention efficacy and promote physical activity in this population.
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Neoplasias Colorretais , Motivação , Humanos , Pessoa de Meia-Idade , Teoria do Comportamento Planejado , Sobreviventes , Exercício Físico , Neoplasias Colorretais/terapiaRESUMO
Organic fluorescent crystals were obtained using single-benzene-based diethyl 2,5-dihydroxyterephthalate (DDT) molecules through crystallization from a droplet of the DDT solution on an Au substrate. To control the size of the DDT crystals, the surface energy of the Au substrate was modified with air plasma treatment, producing a hydrophilic surface and a hydrophobic self-assembled monolayer (SAM) coating. The size of DDT crystals increased as the surface energy of the substrate decreased. The averaged cross-section area of the DDT crystals on the Au substrates increased in the order of the air-plasma-treated substrate (â¼23.43 µm2) < pristine substrate (â¼225.6 µm2) < hydrophobic SAM-coated substrate (â¼2240 µm2). On the other hand, the main emission of the DDT crystals redshifted from blue to green as the crystal size increased, which is related to the aggregation of the DDT crystals. Moreover, the coffee-ring effect during the DDT crystallization was hindered by controlling the solvent evaporation conditions. As examples of the application of the proposed technique, patterned DDT crystals were obtained using selectively patterned hydrophobic and hydrophilic substrates.
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When attempts to lose body fat mass frequently fail, breath acetone (BA) monitoring may assist fat mass loss during a low-carbohydrate diet as it can provide real-time body fat oxidation levels. This randomized controlled study aimed to evaluate the effectiveness of monitoring BA levels and providing feedback on fat oxidation during a three-week low-carbohydrate diet intervention. Forty-seven participants (mean age = 27.8 ± 4.4 years, 53.3% females, body mass index = 24.1 ± 3.4 kg m-2) were randomly assigned to three groups (1:1:1 ratio): daily BA assessment with a low-carbohydrate diet, body weight assessment (body scale (BS)) with a low-carbohydrate diet, and low-carbohydrate diet only. Primary outcome was the change in fat mass and secondary outcomes were the changes in body weight and body composition. Forty-five participants completed the study (compliance rate: 95.7%). Fat mass was significantly reduced in all three groups (allP< 0.05); however, the greatest reduction in fat mass was observed in the BA group compared to the BS (differences in changes in fat mass, -1.1 kg; 95% confidence interval: -2.3, -0.2;P= 0.040) and control (differences in changes in fat mass, -1.3 kg; 95% confidence interval: -2.1, -0.4;P= 0.013) groups. The BA group showed significantly greater reductions in body weight and visceral fat mass than the BS and control groups (allP< 0.05). In addition, the percent body fat and skeletal muscle mass were significantly reduced in both BA and BS groups (allP< 0.05). However, no significant differences were found in changes in body fat percentage and skeletal muscle mass between the study groups. Monitoring BA levels, which could have motivated participants to adhere more closely to the low-carbohydrate diet, to assess body fat oxidation rates may be an effective intervention for reducing body fat mass (compared to body weight assessment or control conditions). This approach could be beneficial for individuals seeking to manage body fat and prevent obesity.
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Acetona , Redução de Peso , Feminino , Humanos , Adulto Jovem , Adulto , Masculino , Testes Respiratórios , Composição Corporal/fisiologia , Peso Corporal , Tecido AdiposoRESUMO
Although increase in physical activity is important to improve prognosis of cardiac patients in addition to hospital-based exercise cardiac rehabilitation, their physical activity levels are not properly understood. This study aimed to examine domain- and intensity-specific physical activity in individuals with coronary heart disease (CHD) and compare them with non-CHD individuals. Data from the Korean National Health and Nutrition Examination Survey (KNHANES) from 2014 to 2019 were analyzed, including 1083 CHD patients and 38,532 non-CHD individuals. The inclusion criteria were age 19 years or older and data not missing for CHD information. Before and after propensity score matching (PSM) for age, sex, body mass index, education, household income, alcohol intake, and smoking status, domain (leisure, work, transportation)-and intensity (moderate, vigorous) -specific physical activity participation levels were compared between individuals with and without CHD. Before PSM, CHD individuals were older, less educated, more sedentary, and participated less in PAs compared to non-CHD individuals. After PSM, CHD individuals had similar levels of domain-specific PAs. However, they had higher work-related PA levels (29.7 ± 209.6 vs. 42.1 ± 291.3 min/week p = 0.022) and more sedentary time (487.2 ± 224.2 vs. 514.1 ± 228.7. p = 0.003) than those without CHD. Subgroup analysis revealed lower leisure-related PA in men with CHD (63.5 ± 165.5 vs. 47.3 ± 140.2, p < 0.05) and higher work-related PA in women with CHD (18.9 ± 159.7 vs. 57.1 ± 397.5, p < 0.01). Among those < 65 years of age, individuals with CHD spent more time sedentary than individuals without CHD. CHD individuals are not physically inactive compared with non-CHD individuals who are similar in sociodemographic status and lifestyle. CHD patients' PA levels may have been underestimated.
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Reabilitação Cardíaca , Doença das Coronárias , Masculino , Humanos , Feminino , Adulto Jovem , Adulto , Inquéritos Nutricionais , Inquéritos e Questionários , Exercício Físico , Doença das Coronárias/epidemiologiaRESUMO
Recurrence of Rathke's cleft cysts (RCC) following surgery is not uncommon. We present a 33-year-old male patient with chronic headache and visual disturbances whose MRI showed mostly cystic, suprasellar mass with peripheral enhancement. Endoscopic extended transsphenoidal approach and tumor resection was performed and RCC was pathologically confirmed postoperatively. Early recurrence was first suspected at 3 months following surgery, and his serial MRIs showed a recurred mass without associated clinical symptoms. Upon further histopathological study, extensive squamous metaplasia and high Ki-67 were seen. Also, in this study, we discuss important factors associated with cyst recurrence following surgery.
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Carbon and semiconductor nanoparticles are promising photothermal materials for various solar-driven applications. Inevitable recombination of photoinduced charge carriers in a single constituent, however, hinders the realization of a greater photothermal effect. Core-shell heterostructures utilizing the donor-acceptor pair concept with high-quality interfaces can inhibit energy loss from the radiation relaxation of excited species, thereby enhancing the photothermal effect. Here, core-shell structures composed of a covellite (CuS) shell (acceptor) and spherical carbon nanoparticle (CP) core (donor) (abbreviated as CP/CuS) are proposed to augment the photothermal conversion efficiency via the Förster resonance energy transfer (FRET) mechanism. The close proximity and spectral overlap of the donor and acceptor trigger the FRET mechanism, where the electronic excitation relaxation energy of the CP reinforces the plasmonic resonance and near-infrared absorption in CuS, resulting in boosting the overall photothermal conversion efficiency. CP/CuS core-shell coated on polyurethane (PU) foam exhibits a total solar absorption of 97.1%, leading to an elevation in surface temperature of 61.6 °C in dry conditions under simulated solar illumination at a power density of 1 kW m-2 (i.e., 1 sun). Leveraging the enhanced photothermal conversion emanated from the energy transfer effect in the core-shell structure, CP/CuS-coated PU foam achieves an evaporation rate of 1.62 kg m-2 h-1 and an energy efficiency of 93.8%. Thus, amplifying photothermal energy generation in core-shell structures via resonance energy transfer can be promising in solar energy-driven applications and thus merits further exploration.
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OBJECTIVE: We examined the effects of short-term KD on exercise efficiency and hormonal response during and after the graded exercise testing. METHODS: Fourteen untrained healthy adults (8 males, 6 females, age 26.4 ± 3.1 [SD] years; BMI 24.8 ± 4.6 kg/m2; peak VO2max 54.0 ± 5.8 ml/kg FFM/min) completed 3-days of a mixed diet (MD) followed by another 3-days of KD after 3-days of washout period. Upon completion of each diet arm, participants underwent graded exercise testing with low- (LIE; 40% of VO2max), moderate- (MIE; 55%), and high-intensity exercise (HIE; 70%). Exercise efficiency was calculated as work done (kcal/min)/energy expenditure (kcal/min). RESULTS: Fat oxidation during the recovery period was higher in KD vs. MD. Despite identical workload during HIE, participants after having KD vs. MD showed higher energy expenditure and lower exercise efficiency (10.1 ± 0.7 vs. 12.5 ± 0.3%, p < .01). After KD, free fatty acid (FFA) concentrations were higher during MIE and recovery vs. resting, and beta-hydroxybutylate (BOHB) was lower at HIE vs. resting. Cortisol concentrations after KD was higher during recovery vs. resting, with no significant changes during graded exercise testing after MD. CONCLUSIONS: Our data suggest that short-term KD is favorable to fat metabolism leading increased circulating FFA and BOHB during LIE to MIE. However, it is notable that KD may cause 1) exercise inefficiency manifested by increased energy expenditure and 2) elevated exercise stress during HIE and recovery. Trial registration: KCT0005172, International Clinical Trials Registry Platform.
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Dieta Cetogênica , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Metabolismo Energético , Exercício Físico/fisiologia , Teste de Esforço , OxirreduçãoRESUMO
We compared the prediction performance of machine learning-based undiagnosed diabetes prediction models with that of traditional statistics-based prediction models. We used the 2014-2020 Korean National Health and Nutrition Examination Survey (KNHANES) (N = 32,827). The KNHANES 2014-2018 data were used as training and internal validation sets and the 2019-2020 data as external validation sets. The receiver operating characteristic curve area under the curve (AUC) was used to compare the prediction performance of the machine learning-based and the traditional statistics-based prediction models. Using sex, age, resting heart rate, and waist circumference as features, the machine learning-based model showed a higher AUC (0.788 vs. 0.740) than that of the traditional statistical-based prediction model. Using sex, age, waist circumference, family history of diabetes, hypertension, alcohol consumption, and smoking status as features, the machine learning-based prediction model showed a higher AUC (0.802 vs. 0.759) than the traditional statistical-based prediction model. The machine learning-based prediction model using features for maximum prediction performance showed a higher AUC (0.819 vs. 0.765) than the traditional statistical-based prediction model. Machine learning-based prediction models using anthropometric and lifestyle measurements may outperform the traditional statistics-based prediction models in predicting undiagnosed diabetes.
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Diabetes Mellitus , Humanos , Inquéritos Nutricionais , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Aprendizado de Máquina , Modelos Estatísticos , Curva ROCRESUMO
Herein, we develop colorimetric multigas sensor arrays assembling chemo-reactive fluorescent patch arrays and 10 × 10 indium gallium zinc oxide phototransistor arrays and apply them to an artificial olfactory platform to recognize five different volatile organic compounds (VOCs). Porous nanofibers, coupled with two organic emitters and emitting fluorescence, rapidly respond to gas-phased VOCs and offer unique fluorescent patterns associated with particular gas conditions, including gas kinds, concentrations, and exposure times by forming patch arrays with different fluorophore component ratios. These VOC-induced fluorescent patterns could be quantified and amplified by indium gallium zinc oxide (IGZO) phototransistor arrays functioning as a signal-generating component, resulting in gas-fingerprint patterns regarding electrical signals. Thus, the pattern library associated with VOCs and their concentration enables us to determine each airborne analyte as the artificial olfactory platform. Therefore, this system could achieve rapid, early quantitative recognition of hazardous gases and be applied as a preventative, portable, and wearable multigas identifier in various fields.
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Gálio , Compostos Orgânicos Voláteis , Óxido de Zinco , Colorimetria , Índio , Corantes Fluorescentes , GasesRESUMO
The efficacy of decompressive craniectomy (DC) for traumatic brain injury (TBI) have been investigated in two recent randomized clinical trials (RCTs) and DC is recommended as an optional treatment for improving overall survival compared to medical treatment. However, the two RCTs enrolled extremely young adults, and the efficacy of DC in older adults remains questionable. Therefore, to identify the efficacy of DC in older adults, we compared patients who received medical care with those who underwent DC after propensity score matching (PSM). From the Korea Multi-center Traumatic Brain Injury Database, 443 patients identified as having intracranial hypertension and a necessity of DC were retrospectively enrolled. The patients were classified into the DC (n = 375) and non-DC (n = 68) groups according to operation records. The PSM was conducted to match the patients in the DC group with those receiving medical care (non-DC). After PSM, the newly matched group (DC, n = 126) was compared with patients without DC (non-DC, n = 63). The mean difference in the logit of the propensity scores (LPS) was 0.00391 and the mean age of enrolled patients were 65 years. The results of the comparative analyses after PSM showed that the 6-month mortality rate of the non-DC group was higher than that of the DC group (61.9% vs. 51.6%, p = 0.179). In terms of favorable outcomes (modified Rankin Scale [mRS] score < 4), the DC group showed a lower rate of favorable mRS scores (11.9% vs. 17.5%, p = 0.296) than the non-DC group.
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Lesões Encefálicas Traumáticas , Craniectomia Descompressiva , Hipertensão Intracraniana , Adulto Jovem , Humanos , Idoso , Pontuação de Propensão , Lesões Encefálicas Traumáticas/cirurgia , Bases de Dados FactuaisRESUMO
BACKGROUND AND AIM: Although resting heart rate (RHR) is associated with prevalence and incidence of diabetes, whether it is associated with undiagnosed diabetes is still unclear. We aimed to investigate whether the RHR is associated with the prevalence of undiagnosed diabetes in a large Korean national dataset. METHODS AND RESULTS: The Korean National Health and Nutrition Examination Survey data from 2008 to 2018 were used. After screening, 51,637 participants were included in this study. The odds ratios and 95% confidence intervals (CIs) for undiagnosed diabetes were calculated using multivariable-adjusted logistic regression analyses. Analyses showed that participants with a RHR of ≥90 bpm showed a 4.00- (95% CI: 2.77-5.77) and 3.21-times (95% CI: 2.01-5.14) higher prevalence of undiagnosed diabetes for men and women, respectively, than those with a RHR of <60 bpm. The linear dose-response analyses showed that each 10-bpm increment in RHR was associated with a 1.39- (95% CI: 1.32-1.48) and 1.28-times (95% CI: 1.19-1.37) higher prevalence of undiagnosed diabetes for men and women, respectively. In the stratified analyses, the positive association between RHR and the prevalence of undiagnosed diabetes was tended to be stronger among those who were younger (age: <40 years) and lean (BMI: <23 kg/m2). CONCLUSIONS: Elevated RHR was significantly associated with a higher prevalence of undiagnosed diabetes in Korean men and women, independent of demographic, lifestyle, and medical factors. Accordingly, the value of RHR as a clinical indicator and health marker, especially in reducing the prevalence of undiagnosed diabetes, is suggestible.
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Diabetes Mellitus , Masculino , Humanos , Adulto , Feminino , Prognóstico , Inquéritos Nutricionais , Frequência Cardíaca , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , República da Coreia/epidemiologia , Fatores de RiscoRESUMO
An enhancement of the local electric field at the metal/dielectric interface of hybrid materials due to the localized surface plasmon resonance (LSPR) phenomenon plays a particularly important role in versatile research fields resulting in a distinct modification of the electrical, as well as optical, properties of the hybrid material. In this paper, we succeeded in visually confirming the LSPR phenomenon in the crystalline tris(8-hydroxyquinoline) aluminum (Alq3) micro-rod (MR) hybridized with silver (Ag) nanowire (NW) in the form of photoluminescence (PL) characteristics. Crystalline Alq3 MRs were prepared by a self-assembly method under the mixed solution of protic and aprotic polar solvents, which could be easily applied to fabricate hybrid Alq3/Ag structures. The hybridization between the crystalline Alq3 MRs and Ag NWs was confirmed by the component analysis of the selected area electronic diffraction attached to high-resolution transmission electron microscope. Nanoscale and solid state PL experiments on the hybrid Alq3/Ag structures using a lab-made laser confocal microscope exhibited a distinct enhancement of the PL intensity (approximately 26-fold), which also supported the LSPR effects between crystalline Alq3 MRs and Ag NWs.
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Using scanning probe lithography (SPL) with KOH ink, this study fabricates aluminum hydroxide (Al(OH)3) nano- and microfeatures on a gold (Au) film that has been deposited on an aluminum (Al) layer. Hydroxyl ions (OH-) from the KOH ink loaded onto the Au film can react with the underlying Al layer to form Al(OH)3 structures due to the decrease in the pH of the reacting solution.1 In this process, Al(OH)3 solidification is governed by the pH of the KOH ink solution, which is affected by its volume. Suitably small volumes (down to hundreds of attoliters) of the KOH ink solution can be applied to the substrate surface using dip-pen nanolithography (DPN) and polymer-pen lithography (PPL). Using DPN and PPL printing with the solid (i.e., gel) and liquid phases of KOH ink, sub-micron- (minimum ≈300 nm) and micron-sized (≥4 µm) Al(OH)3 features can be obtained, respectively. The fabrication of Al(OH)3 structures using the proposed pH-dependent solidification process can be achieved with relatively small volumes in ambient conditions without requiring a previously reported molding process.1,2.
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The charge transfer (CT) process has attracted much attention due to its contribution to the improvement of spectroscopic phenomena such as Raman scattering and fluorescence. A current challenge is understanding what factors can influence CT. Here, it is demonstrated that the enhancement factor (EF) of CT (â¼2000) can reach the level of electromagnetic enhancement (â¼1680) when resonant CT is carried out by (Fermi level energy) band alignment between a metal nanoparticle (NP) and conjugated polymer (polypyrrole (PPy)) nanowire (NW). This band alignment results in an on- or off-resonant CT. As a proof of concept for CT based surface enhanced Raman scattering (SERS) template, the Ag NPs-decorated PPy NW is utilized to effectively enhance the Raman signal of rhodamine 6G (EF of 5.7 × 105). Hence, by means of our demonstration, it is proposed that controlling the band alignment should be considered an important parameter for obtaining a large EF of spectroscopic phenomena.