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We aimed to compare the accuracy and reliability of two segmentation tools for magnetic resonance (MR) volumetry (FreeSurfer and Neurophet AQUA) at two magnetic field strengths (1.5T and 3T). We included 101 patients for the 1.5T–3T dataset and 112 for the 3T–3T dataset from three hospitals and five open-source datasets. The mean volume difference and average volume difference percentage with the change in magnetic field strength were compared between the methods. The hippocampus volume was larger with FreeSurfer than the Neurophet AQUA. In most brain regions, the Neurophet AQUA yielded a smaller average volume difference percentage (all < 10%) than FreeSurfer (all > 10%). The Neurophet AQUA exhibited more stable connectivity and regularity of the segmented components. Regarding volume, the Neurophet AQUA had effect sizes and ICCs comparable to those of FreeSurfer across the magnetic field strengths. With FreeSurfer, the original volume difference was small, whereas the average volume difference percentage was small with the Neurophet AQUA. Image segmentation took 1 h with FreeSurfer and 5 min with the Neurophet AQUA. When choosing an automatic segmentation method, the differences in image processing time and volume variability due to changes in the magnetic field strength of these methods should be considered. [ABSTRACT FROM AUTHOR]

Background: Plasma neurofilament light chain (NfL) is a blood biomarker of neurodegeneration, including Alzheimer's disease. However, its usefulness may be influenced by common conditions in older adults, including amyloid-β (Aβ) deposition and cardiometabolic risk factors like hypertension, diabetes mellitus (DM), impaired kidney function, and obesity. This longitudinal observational study using the Alzheimer's Disease Neuroimaging Initiative cohort investigated how these conditions influence the prognostic capacity of plasma NfL. Methods: Non-demented participants (cognitively unimpaired or mild cognitive impairment) underwent repeated assessments including the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) scores, hippocampal volumes, and white matter hyperintensity (WMH) volumes at 6- or 12-month intervals. Linear mixed-effect models were employed to examine the interaction between plasma NfL and various variables of interest, such as Aβ (evaluated using Florbetapir positron emission tomography), hypertension, DM, impaired kidney function, or obesity. Results: Over a mean follow-up period of 62.5 months, participants with a mean age of 72.1 years (n = 720, 48.8% female) at baseline were observed. Higher plasma NfL levels at baseline were associated with steeper increases in ADAS-Cog scores and WMH volumes, and steeper decreases in hippocampal volumes over time (all p-values < 0.001). Notably, Aβ at baseline significantly enhanced the association between plasma NfL and longitudinal changes in ADAS-Cog scores (p-value 0.005) and hippocampal volumes (p-value 0.004). Regarding ADAS-Cog score and WMH volume, the impact of Aβ was more prominent in cognitively unimpaired than in mild cognitive impairment. Hypertension significantly heightened the association between plasma NfL and longitudinal changes in ADAS-Cog scores, hippocampal volumes, and WMH volumes (all p-values < 0.001). DM influenced the association between plasma NfL and changes in ADAS-Cog scores (p-value < 0.001) without affecting hippocampal and WMH volumes. Impaired kidney function did not significantly alter the association between plasma NfL and longitudinal changes in any outcome variables. Obesity heightened the association between plasma NfL and changes in hippocampal volumes only (p-value 0.026). Conclusion: This study suggests that the prognostic capacity of plasma NfL may be amplified in individuals with Aβ or hypertension. This finding emphasizes the importance of considering these factors in the NfL-based prognostic model for neurodegeneration in non-demented older adults. [ABSTRACT FROM AUTHOR]

Background: Computerized cognitive training (CCT) has been proposed as a potential therapy for cognitive decline. One of the benefits of CCT is a transfer effect, but its mechanism on the memory domain is unclear. This study aimed to investigate the transfer effect of non‐memory multidomain CCT on the memory domain and its neural basis in patients with mild cognitive impairment (MCI) through a randomized controlled trial. Methods: Patients with MCI recruited from memory clinics were randomly assigned to either the CCT or the control group. The CCT group received multidomain CCT training excluding memory training, while the control group read educational books with learning‐based quizzes twice a week for 8 weeks. Participants underwent memory tests yielding a composite score, other cognitive domain tests, non‐cognitive scales, and resting‐state functional magnetic resonance imaging (rsfMRI), at baseline and after intervention. Within‐ and between‐group comparisons, group × time interactions, and seed‐to‐voxel analyses in memory‐involving brain networks were performed. Results: The CCT group showed improvement over the control group in memory domain (Group × time, F = 5.87, P = 0.03, η2 = 0.31), which was related with the increased connectivity in the hippocampal‐frontal and fusiform‐occipital network. No other cognitive and non‐cognitive symptoms differed between groups after adjusting for covariates. Conclusion: Eight weeks of multidomain CCT without memory training improved memory function and restored functional network in the hippocampal and medial temporal region in MCI patients. These results can provide evidence for the transferring ability of CCT on memory functioning with its neural basis. [ABSTRACT FROM AUTHOR]

Background: Altered thyroid hormone levels have been associated with increased risk of Alzheimer's disease (AD) dementia and related cognitive decline. However, the neuropathological substrates underlying the link between thyroid hormones and AD dementia are not yet fully understood. We first investigated the association between serum thyroid hormone levels and in vivo AD pathologies including both beta-amyloid (Aβ) and tau deposition measured by positron emission tomography (PET). Given the well-known relationship between Aβ and tau pathology in AD, we additionally examined the moderating effects of thyroid hormone levels on the association between Aβ and tau deposition. Methods: This cross-sectional study was conducted as part of the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer's Disease (KBASE) cohort. This study included a total of 291 cognitively normal adults aged 55 to 90. All participants received comprehensive clinical assessments, measurements for serum total triiodothyronine (T3), free triiodothyronine (fT3), free thyroxine (fT4), and thyroid-stimulating hormone (TSH), and brain imaging evaluations including [11C]-Pittsburgh compound B (PiB)- PET and [18F] AV-1451 PET. Results: No associations were found between either thyroid hormones or TSH and Aβ and tau deposition on PET. However, fT4 (p = 0.002) and fT3 (p = 0.001) exhibited significant interactions with Aβ on tau deposition: The sensitivity analyses conducted after the removal of an outlier showed that the interaction effect between fT4 and Aβ deposition was not significant, whereas the interaction between fT3 and Aβ deposition remained significant. However, further subgroup analyses demonstrated a more pronounced positive relationship between Aβ and tau in both the higher fT4 and fT3 groups compared to the lower group, irrespective of outlier removal. Meanwhile, neither T3 nor TSH had any interaction with Aβ on tau deposition. Conclusion: Our findings suggest that serum thyroid hormones may moderate the relationship between cerebral Aβ and tau pathology. Higher levels of serum thyroid hormones could potentially accelerate the Aβ-dependent tau deposition in the brain. Further replication studies in independent samples are needed to verify the current results. [ABSTRACT FROM AUTHOR]

Light scattering holds immense significance in various applications, including LED lighting, display enhancement, and solar cell optimization, emphasizing the critical role of understanding scattering mechanisms, especially light–matter interactions, achieving effective optical diffusion. Consequently, the influence of stimuli on material properties, including refractive indices and thermal expansion behavior, has emerged as a pivotal consideration, leading to the development of stimuli‐responsive light scattering modifier. Here, a temperature‐sensitive light scattering modifier composed of poly(methyl methacrylate‐co‐styrene) and poly(ethylene‐co‐vinyl acetate) is presented as scattering particles and matrix, respectively, using a melt‐blending process. Optical properties are evaluated across controlled temperatures 0–70 °C. These findings demonstrate an increasing trend in diffuse transmission and haze as temperatures increased across all light scattering modifiers. Significantly, the optimized light scattering modifier, integrating a dual particle system, showcased uniform reduction gaps in parallel transmission and adjustable haze characteristics across the visible spectrum under temperature control. This optical modifier achieved a total transmission of 92% and adjustable haze levels ranging from 35% to 90% under temperature control. Furthermore, this fabrication of three‐layer films incorporating the light scattering modifier exhibited identical characteristics to the developed light scattering modifier, emphasizing their potential for seamless integration across diverse technological domains. [ABSTRACT FROM AUTHOR]

The discovery of ferroelectricity in HfO2 ultrathin films has gathered considerable interest from the microelectronic industry owing to their compatibility with complementary metal oxide semiconductor technology. However, a significant challenge in utilizing HfO2 thin films for commercial devices is the wakeup effect, which is an increase in polarization with the number of electric field cycles in HfO2-based capacitors. Despite efforts to develop wakeup-free HfO2 thin films, the root cause of this effect remains elusive. Some studies attribute it to the tetragonal (T) to orthorhombic (O) phase transformation, while others suggest it is due to the redistribution of oxygen vacancies within the HfO2 layer during electric field cycling. This study investigated the phase transformation dynamics and oxygen vacancy distributions in TiN/Hf0.5Zr0.5O2/TiN capacitors subjected to electric field cycling using in situ grazing incidence synchrotron x-ray diffraction and ex situ x-ray photoelectron spectroscopy. The as-grown HZO films were crystallized in a mixed phase consisting of monoclinic (M), tetragonal, and orthorhombic fractions. The T-phase volume fraction decreased continuously up to 10k electric field cycles. In contrast, the O-phase fraction increased within the first 100 cycles and then stabilized with further cycling. The redistribution of oxygen vacancies occurred continuously throughout the cycling process. The results revealed that continuous oxygen vacancy redistribution during electric field cycling resulted in phase transformation between the T-, O-, and M-phases. The study provides insight into the phase transformation dynamics and oxygen vacancy redistribution in TiN/Hf0.5Zr0.5O2/TiN capacitors during electric field cycling, shedding light on the underlying mechanisms of the wakeup effect. [ABSTRACT FROM AUTHOR]

Epitaxial buffer layers such as ceria (CeO2)/yttria-stabilized zirconia (YSZ) allow the direct integration of functional oxide single crystal thin films on silicon (Si). Microcracks in the buffer layer, often evolving from the large thermal tensile stress, are detrimental to the integration of high-quality complex oxide thin films on Si. In this study, we investigated the evolution of microcracks in sputter-grown epitaxial CeO2 layers by systematically varying the sputtering power and thickness of CeO2 thin films on YSZ single crystal (low thermal mismatch) and YSZ-buffered Si (high thermal mismatch) substrates. Using a plane stress model, we revealed that as the sputtering power increased, the epitaxial CeO2 thin films tended to be more compressively strained at the growth temperature. This could accommodate the tensile strain arising during cooling to room temperature, thereby suppressing the evolution of microcracks. Our result provides not only a method to suppress microcracks in the oxide heterostructure on Si, but also a tool to control their strain state, by controlling their growth parameters. [ABSTRACT FROM AUTHOR]

Moderately elevated albuminuria (30–300 mg/g) is a marker of renal dysfunction and a risk factor of cardiovascular disease. Additionally, several recent studies have reported a relationship between moderately elevated albuminuria and triglyceride (TG) levels. Therefore, we aimed to evaluate the relationship between the urine albumin-to-creatinine ratio (UACR) and total cholesterol (TC), TG, and high-density lipoprotein C (HDL-C) levels. We analyzed data from 19,340 patients from the 2011–2014 and 2019–2020 from the Korea National Health and Nutrition Examination Surveys. Multivariate linear regression analysis showed that the UACR was positively associated with TC and TG levels and negatively associated with HDL-C levels in both Korean women and men. These results were reanalyzed according to the degree of proteinuria (normal, moderately elevated albuminuria, and severely elevated albuminuria (≥ 300 mg/g)). We found a positive relationship between UACR and TC and TG levels, but a negative association with HDL-C levels, except for TC (moderately elevated albuminuria) and HDL-C (moderately elevated albuminuria) in Korean men and TC (severely elevated albuminuria), TG (severely elevated albuminuria), and HDL-C (normal range albuminuria) in Korean women. The correlation between albuminuria and lipid profiles became more evident as albuminuria shift from normal to the severely elevated albuminuria. Thus our multivariate linear regression analysis showed that lipid profiles (TG, TC, and HDL-C levels) were associated with the UACR. [ABSTRACT FROM AUTHOR]

Fine‐tuning the sensing properties of carbon dioxide (CO2) colorimetric sensors is a challenging task. In this study, a short synthetic route is developed for CO2‐responsive nanoparticles with diverse sensitivity and detection range across a wide range of CO2 concentrations. This involves the addition of oily liquids as inter‐chain spacers, which changes the diffusivity of CO2 gas into the sensing matrices without other chemical modifications. R values and the limit of detection (LOD) are estimated from Euclidean distance (ED) curves, indicating a ten‐fold difference in sensitivity. Optical and physical analyses revealed that these results arise from intercalating inter‐chain spacers between polymeric chains and modifying the gas diffusivity. Furthermore, the sensitivity and detection range can be easily tuned by mixing two CO2‐responsive nanoparticles having different inter‐chain spacers, allowing the fabrication of the sensors with subtle differences in sensitivity and detection range. Based on these results, a CO2 level meter with a horizontal linear gauge that allows visible identification of the level of CO2 over the entire range of CO2 concentrations (from 0% to 100%) is developed. Consequently, the findings will be helpful in achieving a better understanding of gas information and finding an effective way to control the characteristics of colorimetric sensors. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate gender differences in the biomechanics of lower limb joints during stair ascent, focusing on the distribution of joint loads. Thirty-six young subjects (18 males and 18 females) ascended instrumented stairs while kinematic and kinetic data were measured. Mechanical variables of the lower limb joints and body posture on the sagittal plane were compared between genders, and their associations were also investigated. Female subjects exerted more mechanical work, power, and joint moment than male subjects at the knee joint, while males exerted more at the hip joint. Females and males showed a longer moment arm of ground reaction force at the knee and hip joints, respectively. The moment arm, but not the magnitude, of ground reaction force was strongly associated with the joint moment (r = 0.80–0.97). Females exhibited a more crouched stance limb (lower heel lift, greater ankle dorsiflexion, and knee flexion) than males. A more crouched and extended lower limb posture was found to be correlated with a longer moment arm at the knee and hip joints, respectively. Half of the variance in moment arm could be explained by the heel lift angle. The results indicate that females allocate greater work to the knee joint but less to the hip joint than males do in order to elevate body mass to a higher step during stair ascent. The work distribution strategy appears to be influenced significantly by posture, particularly the choice of foot contact method: heel-toe standing in females and toe standing in males. [ABSTRACT FROM AUTHOR]

Background: Neuropsychiatric symptoms and delusions are highly prevalent among people with dementia. However, multiple roots of neurobiological bases and shared neural basis of delusion and cognitive function remain to be characterized. By utilizing a fine-grained multivariable approach, we investigated distinct neuroanatomical correlates of delusion symptoms across a large population of dementing illnesses. Methods: In this study, 750 older adults with mild cognitive impairment and Alzheimer's disease completed brain structural imaging and neuropsychological assessment. We utilized principal component analysis followed by varimax rotation to identify the distinct multivariate correlates of cortical thinning patterns. Five of the cognitive domains were assessed whether the general cognitive abilities mediate the association between cortical thickness and delusion. Results: The result showed that distributed thickness patterns of temporal and ventral insular cortex (component 2), inferior and lateral prefrontal cortex (component 1), and somatosensory-visual cortex (component 5) showed negative correlations with delusions. Subsequent mediation analysis showed that component 1 and 2, which comprises inferior frontal, anterior insula, and superior temporal regional thickness accounted for delusion largely through lower cognitive functions. Specifically, executive control function assessed with the Trail Making Test mediated the relationship between two cortical thickness patterns and delusions. Discussion: Our findings suggest that multiple distinct subsets of brain regions underlie the delusions among older adults with cognitive impairment. Moreover, a neural loss may affect the occurrence of delusion in dementia largely due to impaired general cognitive abilities. [ABSTRACT FROM AUTHOR]

Background The prevalence of atrial fibrillation (AF) in patients with end-stage kidney disease (ESKD) is high and increasing. However, evidence regarding oral anticoagulant (OAC) use in these patients is insufficient and conflicting. Methods This retrospective cohort study included patients in the Korea National Health Insurance System diagnosed with AF after ESKD onset from January 2007 to December 2017. The primary outcome was all-cause death. Secondary outcomes were ischaemic stroke, hospitalization for major bleeding and major adverse cardiovascular events (MACE). Outcomes were compared between OAC users and non-users using 6-month landmark analysis and 1:3 propensity score matching (PSM). Results Among patients with ESKD and AF, the number of prescribed OACs increased 2.3-fold from 2012 (n  = 3579) to 2018 (n  = 8341) and the proportion of direct OACs prescribed increased steadily from 0% in 2012 to 51.4% in 2018. After PSM, OAC users had a lower risk of all-cause death {hazard ratio [HR] 0.67 [95% confidence interval (CI) 0.55–0.81]}, ischaemic stroke [HR 0.61 (95% CI 0.41–0.89)] and MACE [HR 0.70 (95% CI 0.55–0.90)] and no increased risk of hospitalization for major bleeding [HR 0.99 (95% CI 0.72–1.35)] compared with non-users. Unlike warfarin, direct OACs were associated with a reduced risk of all-cause death and hospitalization for major bleeding. Conclusions In patients with ESKD and AF, OACs were associated with reduced all-cause death, ischaemic stroke and MACE. [ABSTRACT FROM AUTHOR]

In recent times, the utilization of three-dimensional (3D) printing technology, particularly a variant using digital light processing (DLP), has gained increasing fascination in the realm of microfluidic research because it has proven advantageous and expedient for constructing microscale 3D structures. The surface wetting characteristics (e.g., contact angle and contact angle hysteresis) of 3D-printed microstructures are crucial factors influencing the operational effectiveness of 3D-printed microfluidic devices. Therefore, this study systematically examines the surface wetting characteristics of DLP-based 3D printing objects, focusing on various printing conditions such as lamination (or layer) thickness and direction. We preferentially examine the impact of lamination thickness on the surface roughness of 3D-printed structures through a quantitative assessment using a confocal laser scanning microscope. The influence of lamination thicknesses and lamination direction on the contact angle and contact angle hysteresis of both aqueous and oil droplets on the surfaces of 3D-printed outputs is then quantified. Finally, the performance of a DLP 3D-printed microfluidic device under various printing conditions is assessed. Current research indicates a connection between printing parameters, surface roughness, wetting properties, and capillary movement in 3D-printed microchannels. This correlation will greatly aid in the progress of microfluidic devices produced using DLP-based 3D printing technology. [ABSTRACT FROM AUTHOR]

Background: White matter (WM) microstructural changes in the hippocampal cingulum bundle (CBH) in Alzheimer's disease (AD) have been described in cohorts of largely European ancestry but are lacking in other populations. Methods: We assessed the relationship between CBH WM integrity and cognition or amyloid burden in 505 Korean older adults aged ≥ 55 years, including 276 cognitively normal older adults (CN), 142 with mild cognitive impairment (MCI), and 87 AD patients, recruited as part of the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's disease (KBASE) at Seoul National University. Results: Compared to CN, AD and MCI subjects showed significantly higher RD, MD, and AxD values (all p-values < 0.001) and significantly lower FA values (left p ≤ 0.002, right p ≤ 0.015) after Bonferroni adjustment for multiple comparisons. Most tests of cognition and mood (p < 0.001) as well as higher medial temporal amyloid burden (p < 0.001) were associated with poorer WM integrity in the CBH after Bonferroni adjustment. Conclusion: These findings are consistent with patterns of WM microstructural damage previously reported in non-Hispanic White (NHW) MCI/AD cohorts, reinforcing existing evidence from predominantly NHW cohort studies. [ABSTRACT FROM AUTHOR]

Background: White matter (WM) microstructural changes in the hippocampal cingulum bundle (CBH) in Alzheimer's disease (AD) have been described in cohorts of largely European ancestry but are lacking in other populations. Methods: We assessed the relationship between CBH WM integrity and cognition or amyloid burden in 505 Korean older adults aged ≥ 55 years, including 276 cognitively normal older adults (CN), 142 with mild cognitive impairment (MCI), and 87 AD patients, recruited as part of the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's disease (KBASE) at Seoul National University. Results: Compared to CN, AD and MCI subjects showed significantly higher RD, MD, and AxD values (all p-values < 0.001) and significantly lower FA values (left p ≤ 0.002, right p ≤ 0.015) after Bonferroni adjustment for multiple comparisons. Most tests of cognition and mood (p < 0.001) as well as higher medial temporal amyloid burden (p < 0.001) were associated with poorer WM integrity in the CBH after Bonferroni adjustment. Conclusion: These findings are consistent with patterns of WM microstructural damage previously reported in non-Hispanic White (NHW) MCI/AD cohorts, reinforcing existing evidence from predominantly NHW cohort studies. [ABSTRACT FROM AUTHOR]

The use of a contralateral cane has demonstrated a reduction in the external knee adduction moment (KAM) in patients with knee osteoarthritis. However, the underlying mechanism remains unclear. This study aimed to investigate the specific mechanism in healthy young subjects. Sixteen healthy young participants were included in this study. They walked on a floor under three loading conditions: no cane and with cane loads equivalent to 5% and 10% of body weight. Change in posture and kinetic features of ipsilateral leg were examined at two instants of ground reaction force (GRF) peaks. The results revealed a substantial decrease (40–55%) in both KAM and moment arm, whereas only 12% decrease was observed in GRF with 10% cane loading. Furthermore, KAM was strongly correlated with moment arm (r = 0.97, p < 0.01), but not with GRF (p > 0.05). The reduction in moment arm could be attributed to a medial shift of knee joint and/or a lateral shift of GRF. At the maximum cane loading, medial shift in the knee joint center was significant (p < 0.001), while any shift in GRF was insignificant (p > 0.80). The results suggest that the primary factor contributing to the reduction in KAM is the decrease in moment arm among healthy young subjects. Importantly, the reduction in moment arm was primarily induced by a medial shift of the knee joint center, emphasizing the significance of postural changes. [ABSTRACT FROM AUTHOR]

Cobalt-57 (57Co) has emerged as a promising radionuclide and as an isotope for diagnostic and calibration sources. Herein, we report the production, chemical separation, and quality control of 57Co in an RFT-30 cyclotron facility. 57Co is produced via (p, 2p) nuclear reaction using an enriched 58Ni target material. Electrodeposits of 58Ni on Ag backing were obtained and irradiated using an incident proton beam energy of 17.4 MeV. The chemical separation of 57Co and recovery of the enriched 58Ni target material were simplified via a solid-phase extraction method. The radionuclide purity (> 99.9%) and metallic impurities (< 25 ppb) of purified 57Co were confirmed. [ABSTRACT FROM AUTHOR]

Introduction: Distal tibial fractures make up approximately 3% to 10% of all tibial fractures or about 1% of lower extremity fractures. MIPO is an appropriate procedure and method to achieve stable metal plate fixation and osseointegration by minimizing soft tissue damage and vascular integrity at the fracture site. MIPO to the medial tibia during distal tibial fractures induces skin irritation due to the thickness of the metal plate, which causes discomfort and pain on the medial side of the distal leg, and if severe, complications such as infection and skin defect may occur. The reverse sural flap is a well-researched approach for covering defects in the lower third of the leg, ankle, and foot. Materials and Methods: Among 151 patients with distal tibia fractures who underwent minimally invasive metal plate fixation, soft tissue was injured due to postoperative complications. We treated 13 cases with necrosis and exposed metal plates by retrograde nasogastric artery flap surgery. For these patients, we collected obligatory patient records, radiological data, and wound photographs of the treatment results and complications of reconstructive surgery. Results: In all the cases, flap survival was confirmed at the final outpatient follow-up. The exposed area of the metal plate was well coated, and there was no plate failure due to complete necrosis. Three out of four women complained of aesthetic dissatisfaction because the volume of the tunnel through which the skin mirror passed and the skin plate itself were thick. In two cases, defatting was performed to reduce the thickness of the plate while removing the metal plate. Conclusions: Metal plate exposure after distal tibial fractures have been treated with minimally invasive metal plate fusion and can be successfully treated with retrograde nasogastric artery flaps, and several surgical techniques are used during flap surgery. [ABSTRACT FROM AUTHOR]

Individuals with end-stage kidney disease (ESKD) on dialysis are at a high risk of developing foot ulcerations and undergoing subsequent lower extremity amputation (LEA), which can exert significant impacts on their quality of life and contribute to rising healthcare costs. We aimed to identify risk factors associated with LEA in patients with ESKD to predict LEA progression and eventually prevent it. We used 18 years (2002–2019) of data from the Korean National Health Insurance Service (KNHIS). Data were collected from patients with ESKD who underwent renal replacement therapy (RRT) and had no history of amputation caused by trauma or toxins. The risk factors were compared between patients with or without LEA. We collected data from 220,838 patients newly diagnosed with ESKD, including 6348 in the LEA group and 214,490 in the non-LEA group. The total incidence of LEA was 2.9%. Older age, male gender, lower income, non-metropolitan residence, diabetes mellitus, dialysis treatment (compared to kidney transplantation), microvascular disease, peripheral vascular disease, endovascular procedure, and endovascular operation were associated with an increased risk of LEA. Thus, individuals with ESKD who are at a higher risk for LEA should be closely monitored, and kidney transplantation should be considered as a preventative measure. [ABSTRACT FROM AUTHOR]

The discovery of hafnium oxide-based ferroelectrics has resulted in the pursuit of ferroelectric field-effect transistors with higher scalability, lower power consumption, and enhanced switching speed. An in-depth understanding of ferroelectric polarization switching kinetics is essential for both scientific and technological purposes. Polarization switching is analyzed based on the nucleation-limited switching model with a Lorentzian distribution of logarithmic switching times. The activation field governing the switching kinetics is explained by a dependence on the density of oxygen vacancies, which are caused by various annealing temperatures. This indicates that oxygen vacancies can be a dominant factor in the polarization switching of Si-doped HfO2 films. [ABSTRACT FROM AUTHOR]

Facial expressions play a crucial role in the diagnosis of mental illnesses characterized by mood changes. The Facial Action Coding System (FACS) is a comprehensive framework that systematically categorizes and captures even subtle changes in facial appearance, enabling the examination of emotional expressions. In this study, we investigated the association between facial expressions and depressive symptoms in a sample of 59 older adults without cognitive impairment. Utilizing the FACS and the Korean version of the Beck Depression Inventory-II, we analyzed both "posed" and "spontaneous" facial expressions across six basic emotions: happiness, sadness, fear, anger, surprise, and disgust. Through principal component analysis, we summarized 17 action units across these emotion conditions. Subsequently, multiple regression analyses were performed to identify specific facial expression features that explain depressive symptoms. Our findings revealed several distinct features of posed and spontaneous facial expressions. Specifically, among older adults with higher depressive symptoms, a posed face exhibited a downward and inward pull at the corner of the mouth, indicative of sadness. In contrast, a spontaneous face displayed raised and narrowed inner brows, which was associated with more severe depressive symptoms in older adults. These findings suggest that facial expressions can provide valuable insights into assessing depressive symptoms in older adults. [ABSTRACT FROM AUTHOR]

Polyglycolic acid (PGA) is a promising polymer in the packaging field owing to its excellent hydrolysis, heat resistance, and gas barrier properties, but it is limited in application due to its poor toughness. For this reason, a covalently bonded chain extender is introduced to increase compatibility with flexible polymers. However, covalent bonds are unfavorable for application to degradable plastics because of the energy required for reverse reactions. Therefore, we intended to effectively control the ductility of blending plastics by using a novel ionic chain extender with a relatively weaker non-covalent bond than the existing covalent bond. Polycaprolactone (PCL), which has biodegradability and flexibility, was selected as a blending polymer. For comparison, a covalently reactive chain extender (G-CE) and a non-covalently ionic chain extender (D-CE) were synthesized and compounded with blending plastics. Each chain extender improved the compatibility between PGA and PCL, and the ductility of the PGA/PCL blending plastics was more greatly enhanced with non-covalently bonded D-CE than with covalently bonded G-CE. At this time, the ductility of the PGA/PCL(90/10) blending plastic without CE was 7.2%, the ductility of blending plastic with D-CE (10D) was 26.6%, and the ductility of blending plastic with G-CE (10G) was 18.6%. Therefore, it was confirmed that the novel ionic chain extender inducing non-covalent bonds improves the compatibility between PGA and PCL and is more advantageous in enhancing ductility through a reversible reaction. [ABSTRACT FROM AUTHOR]

Background: Low body mass index (BMI) or underweight status in late life is associated with an increased risk of dementia or Alzheimer's disease (AD). However, the relationship between late-life BMI and prospective longitudinal changes of in-vivo AD pathology has not been investigated. Methods: This prospective longitudinal study was conducted as part of the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer's Disease (KBASE). A total of 194 cognitive normal older adults were included in the analysis. BMI at baseline was measured, and two-year changes in brain Aβ and tau deposition on PET imaging were used as the main outcomes. Linear mixed-effects (LME) models were used to examine the relationships between late-life BMI and longitudinal change in AD neuropathological biomarkers. Results: A lower BMI at baseline was significantly associated with a greater increase in tau deposition in AD-signature region over 2 years (β, -0.018; 95% CI, -0.028 to -0.004; p =.008), In contrast, BMI was not related to two-year changes in global Aβ deposition (β, 0.0002; 95% CI, -0.003 to 0.002, p =.671). An additional exploratory analysis for each sex showed lower baseline BMI was associated with greater increases in tau deposition in males (β, -0.027; 95% CI, -0.046 to -0.009; p = 0.007), but not in females. Discussion: The findings suggest that lower BMI in late-life may predict or contribute to the progression of tau pathology over the subsequent years in cognitively unimpaired older adults. [ABSTRACT FROM AUTHOR]

The ongoing COVID‐19 has not only caused millions of deaths worldwide, but it has also led to economic recession and the collapse of public health systems. The vaccines and antivirals developed in response to the pandemic have improved the situation markedly; however, the pandemic is still not under control with recurring surges. Thus, it is still necessary to develop therapeutic agents. In our previous studies, we designed and synthesized a series of novel 2‐anilinoquinazolin‐4(3H)‐one derivatives, and demonstrated inhibitory activity against severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and MERS‐CoV in vitro. We then conducted in vivo studies using modified compounds that are suitable for oral administration. These compounds demonstrated no toxicity in rats and inhibited viral entry. Here, we investigated the in vivo efficacy of these drug candidates against SARS‐CoV‐2. Three candidate drugs, 7‐chloro‐2‐((3,5‐dichlorophenyl)amino)quinazolin‐4(3H)‐one (1), N‐(7‐chloro‐4‐oxo‐3,4‐dihydroquinazolin‐2‐yl)‐N‐(3,5‐dichlorophenyl)acetamide (2), and N‐(7‐chloro‐4‐oxo‐3,4‐dihydroquinazolin‐2‐yl)‐N‐(3,5‐difluorophenyl)acetamide (3) were administered orally to hACE2 transgenic mice at a dose of 100 mg/kg. All three drugs improved survival rate and reduced the viral load in the lungs. These results show that the derivatives possess in vivo antiviral efficacy similar to that of molnupiravir, which is currently being used to treat COVID‐19. Overall, our data suggest that 2‐anilinoquinazolin‐4(3H)‐one derivatives are promising as potential oral antiviral drug candidates against SARS‐CoV‐2 infection. [ABSTRACT FROM AUTHOR]

In colonoscopy, computer vision and artificial intelligence technology have enabled the automatic detection of the location of polyps and their visualization. These advancements have facilitated considerable research in the field. However, deep learning models used in the segmentation problem for capturing various patterns of polyps are becoming increasingly complex, which has rendered their operation in real time difficult. To identify and overcome this problem, a study was conducted on a model capable of precise polyp segmentation while increasing its processing speed. First, an efficient, high-performance, and lightweight model suitable for the segmentation of polyps was sought; the performance of existing segmentation models was compared and combined to obtain a learning model that exhibited good accuracy and speed. Next, hyperparameters were found for the MobileNetV3-encoder-based DeepLabV3+ model and, after tuning the hyperparameters, quantitative and qualitative results were compared, and the final model was selected. The experimental results showed that this model achieved high accuracy, with a Dice coefficient of 93.79%, while using a limited number of parameters and computational resources. Specifically, the model used 6.18 million parameters and 1.623 giga floating point operations for the CVC-ClinicDB dataset. This study revealed that increasing the amount of computation and parameters of the model did not guarantee unconditional performance. Furthermore, for the search and removal of polyps in cases in which morphological information is critical, an efficient model with low model complexity and high accuracy was proposed for real-time segmentation. [ABSTRACT FROM AUTHOR]

Background: Ankle-brachial index (ABI), an indicator of atherosclerosis or arterial stiffness, has been associated with Alzheimer's disease (AD) dementia and related cognitive impairment. Nevertheless, only limited information is available regarding its contribution to brain alterations leading to cognitive decline in late-life. Objective: We aimed to investigate the relationship of ABI with in vivo AD pathologies and cerebrovascular injury in cognitively impaired older adults. Methods: Total 127 cognitively impaired (70 mild cognitive impairment and 57 AD dementia) individuals, who participated in an ongoing prospective cohort study, were included. All participants underwent comprehensive clinical and neuropsychological assessment, ABI measurement, apolipoprotein E (APOE) ɛ4 genotyping, and multi-modal brain imaging including [11C] Pittsburgh Compound B (PiB)-positron emission tomography (PET) and [18F] fludeoxyglucose (FDG)-PET, and MRI. Results: General linear model analysis showed significant relationship between ABI strata (low ABI: <1.00, normal ABI: 1.00–1.29, and high ABI: ≥1.30) and AD-signature region cerebral glucose metabolism (AD-CM), even after controlling age, sex, clinical dementia rating–sum of box, and APOE ɛ4 positivity (p = 0.029). Post hoc comparison revealed that low ABI had significantly lower AD-CM than middle and high ABI, while no difference of AD-CM was found between middle and high ABI. There was no significant difference of global Aβ deposition, AD-signature region cortical thickness, and white matter hyperintensity volume between the three ABI strata. Conclusion: Our findings suggest that lower ABI, likely related to atherosclerosis, may contribute to the aggravation of AD-related regional neurodegeneration in cognitively impaired older adults. [ABSTRACT FROM AUTHOR]

Background: Low bone mass is common in malnourished patients with chronic kidney disease (CKD) and can lead to a higher risk of fractures. Elderly and CKD patients have the same risk factors for protein-energy wasting, sarcopenia, and osteoporosis. Here, we investigated the association between phase angle (PhA) and bone mineral density (BMD) in dialysis-naïve patients with CKD stage 5 (CKD5) and identified a statistical relationship between PhA and age, which affects bone density. Methods: Bio-impedance spectroscopy for evaluating body composition and PhA and dual-energy X-ray absorptiometry for determining the BMD were simultaneously performed in 167 consecutive patients (mean age, 59.65 ± 13.98 years; women, 40.1%). Two-way analysis of variance (ANOVA) was conducted to assess the potential interaction effect of PhA and age on femoral neck BMD (FN-BMD). Results: Our results showed that PhA and age were independently associated with FN-BMD and T-score in multiple linear regressions analyses. A significant interaction effect of PhA and age on FN-BMD was found on two-way ANOVA (p = 0.028). The average BMD values for the first and second tertiles of the PhA were higher in the young versus elderly group, whereas patients in the elderly group had higher BMD in the third tertiles. Conclusions: A relationship was noted between PhA and BMD in patients with advanced-stage CKD. The effect of PhA level on FN-BMD differed between elderly and young patients. Our study suggested that higher PhA levels could be a marker explaining the maintenance of good bone health in elderly patients with CKD5. Further longitudinal analyses are needed to determine whether PhA predicts the risk of CKD-MBD-related fractures during CKD progression. [ABSTRACT FROM AUTHOR]

(1) Background: Achilles tendon rupture is a common sports injury that may result in severe disability. The overall incidence of Achilles tendon rupture is increasing as a result of growing sports participation. However, cases of spontaneous bilateral Achilles tendon rupture with no underlying disease or risk factors, such as systemic inflammatory disease, steroid or (fluoro)quinolone antibiotics use, are rare. (2) Objective: Here, we report a case of a Taekwondo athlete's bilateral Achilles tendon rupture after kicking and landing. By sharing the experience of treatment and the patient's course, we suggest one of the possible treatment options and the need to establish a treatment method. (3) Procedure: A 23-year-old male Taekwondo athlete visited the hospital, presenting foot plantar flexion failure and severe pain in both tarsal joints, which had occurred upon kicking and landing on both feet earlier that day. During surgery, no degenerative changes or denaturation were observed in the ruptured areas of the Achilles tendons. Bilateral surgery was performed using the modified Bunnel method on the right side and minimum-section suturing on the left side was performed using the Achillon system, followed by lower limb casting. (4) Result: Good outcomes were observed on both sides at 19 months postoperatively. (5) Conclusion: The possibility of bilateral Achilles tendon rupture during exercise in young subjects with no risk factors should be acknowledged, especially in association with landing. In addition, in athletes, even if there is a possibility of complications, surgical treatment should be considered for functional recovery. [ABSTRACT FROM AUTHOR]

Aim: The neurobiological substrates underlying the relationship of circadian rest‐activity rhythm (RAR) alteration with accelerated late‐life cognitive decline are not clearly understood. In the present study, the longitudinal relationship of objectively measured circadian RAR with in vivo Alzheimer disease (AD) pathologies and cerebrovascular injury was investigated in older adults without dementia. Methods: The present study included 129 participants without dementia who participated in the KBASE (Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer's Disease) cohort. All participants underwent actigraphy at baseline and two consecutive [11C] Pittsburgh compound‐B positron emission tomography (PET), [18F] fluorodeoxyglucose‐PET, magnetic resonance imaging, and Mini‐Mental State Examination (MMSE) at baseline and at a 2‐year follow‐up assessment. The associations of circadian RAR with annualized change in neuroimaging measures including global amyloid‐beta retention, AD‐signature region cerebral glucose metabolism (AD‐CM), and white matter hyperintensity volume were examined. Results: Delayed acrophase at baseline was significantly associated with greater annualized decline of AD‐CM over a 2‐year period, but not with that of other neuroimaging measures. In contrast, other circadian RAR parameters at baseline had no association with annualized change of any neuroimaging measures. Annualized decline of AD‐CM was also significantly positively associated with the annual change in MMSE scores. Furthermore, a mediation analysis showed that greater reduction in AD‐CM mediated the effect of delayed acrophase at baseline on faster decline of MMSE score. Conclusion: The findings indicate that delayed acrophase in late life may cause or predict hypometabolism at AD‐signature brain regions, which underlies cognitive decline in the near future. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to investigate the predictive efficacy of shear-wave elastography, superb microvascular imaging (SMI), and CEUS for allograft rejection in kidney transplants without graft dysfunction. Methods: From January 2021 to November 2021, 72 consecutive patients who underwent both allograft biopsy and ultrasound were evaluated. Blood test results were obtained within a week of the ultrasound examinations, which were performed before the protocol biopsy. Resistive index (RI), tissue viscoelasticity, vascular index, and quantitative CEUS parameters were measured. Patients were divided based on biopsy results into the rejection and non-rejection groups. Results: Among the 72 patients, 21 patients had pathological characteristics of acute rejection. RI of allograft was significantly higher in the rejection group (p = 0.007), compared to the non-rejection group. There were no significant between-group differences in vascular indices of SMI, mean elasticity, and mean viscosity. Meanwhile, among the parameters obtained by the time-intensity curve on CEUS, the cortical and medullary ratios of average contrast signal intensity, peak enhancement, wash-in area AUC, wash-in perfusion index, wash-out AUC, and wash-in and wash-out AUC were significantly different between the two groups (p < 0.05). In the receiver operating characteristic curve analysis for predicting allograft rejection, the AUC was 0.853 for the combination of six CEUS parameters, RI, and blood urea nitrogen. Conclusions: Among non-invasive quantitative ultrasound measurements, CEUS parameters are the most useful for diagnosing subclinical allograft rejection. Furthermore, the combination of CEUS parameters, RI, and blood urea nitrogen may be helpful for the early detection of renal allograft rejection. Key Points: • Among non-invasive quantitative ultrasound measurements, CEUS parameters are the most useful for the diagnosis of subclinical allograft rejection. • On CEUS, the C/M ratios of MeanLin, PE, WiAUC, WiPI, WoAUC, and WiWoAUC are significantly lower in the rejection group; the combination of these showed reliable predictive performance for rejection. • The combination of CEUS parameters, RI, and BUN has a high predictive capability for subclinical allograft rejection. [ABSTRACT FROM AUTHOR]

Introduction: The association between microalbuminuria and cardiovascular disease (CVD) is accumulating in various patient populations. However, when stratified by sex, the relationship between microalbuminuria and CVD remains unclear. Method: We obtained data from the 2011–2014 and 2019–2020 Korea National Health and Nutrition Examination Survey (KNHANES). Microalbuminuria was measured based on spot urine albumin-creatinine ratio (UACR). The Framingham risk score (FRS) model was implemented to evaluate the CVD risk. Linear and logistic regression models were used to identify the associations of microalbuminuria status with cardiometabolic predictors and CVD status determined by the FRS score. Results: Among 19,340 representative Korean participants, the (UACR) in Korean women and men with history of CVD was higher than in those without history of CVD. Among patients without history of CVD, multivariate regression analysis showed that a high UACR was related to older age, lower high-density lipoprotein cholesterol level, higher total cholesterol level, higher systolic blood pressure, higher prevalence of current smoking, higher prevalence of diabetes, and higher anti-hypertensive medication use in both women and men. The UACR showed a positive linear correlation with the Framingham risk score in both women and men. Conclusion: The presence of microalbuminuria was significantly associated with the cardiometabolic risk factors and the increased risk of CVD evaluated by FRS model in both women and men in a nationally representative sample of Korea. [ABSTRACT FROM AUTHOR]

Epitaxial complex oxide heterostructures on Si are an excellent platform for the realization of multifunctional electronic devices to exploit the unique functionalities of the oxides that Si does not possess. It is often necessary to make patterns of epitaxial films on selected areas of Si. Here, a path towards the selective area epitaxial growth of complex oxide heterostructures on Si using a hard mask lift-off technique is reported. A water-soluble oxide (Sr3Al2O6) is used as a lift-off hard mask that can survive the high temperature (~ 750 °C) and oxidizing environments for epitaxial oxide growth and be selectively etched away subsequently using deionized water. It is found that the epitaxial growth of yttria-stabilized zirconia (YSZ) buffer layers on Si is very sensitive to organic residues formed during photolithography. Island patterns of epitaxial (La, Sr)MnO3/CeO2/YSZ heterostructures are successfully fabricated on Si through the use of oxygen plasma treatment to remove residues. A simple and low-cost method to pattern complex oxide single crystals integrated on Si for the realization of multifunctional oxide-integrated electronics is provided in this study. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to investigate the associations of enlarged perivascular spaces (EPVS) in the basal ganglia (BG) and centrum semiovale (CSO) with beta‐amyloid (Aβ) and tau deposition in older adults with a diverse cognitive spectrum. Methods: A total of 163 (68 cognitively normal and 95 cognitively impaired) older participants underwent [11C] Pittsburgh compound B and [18F] AV‐1451 PET, and MRI. EPVS in the BG and CSO and other small vessel disease markers, such as white matter hyperintensities, lacunes, and deep and lobar microbleeds, were assessed. Results: Increased EPVS in the BG showed a significant association with lower cerebral tau deposition, even after controlling for other small vessel disease markers. Further exploratory analyses showed that this association was significant in cognitively impaired, Aβ‐positive, or APOE4‐positive individuals, but not significant in the cognitively normal, Aβ‐negative, or APOE4‐negative participants. In contrast to EPVS in the BG, EPVS in the CSO did not have any relationship with cerebral tau deposition. In addition, none of the two types of EPVS were associated with cerebral Aβ deposition. Conclusion: Brain tau deposition appears to be reduced with increased EPVS in the BG, especially in individuals with cognitive impairment, pathological amyloid burden, or genetic Alzheimer's disease risk. [ABSTRACT FROM AUTHOR]

Background: Polypropylene (PP) is used in various products such as disposable containers, spoons, and automobile parts. The disposable masks used for COVID-19 prevention mainly comprise PP, and the disposal of such masks is concerning because of the potential environmental pollution. Recent reports have suggested that weathered PP microparticles can be inhaled, however, the inhalation toxicology of PP microparticles is poorly understood. Results: Inflammatory cell numbers, reactive oxygen species (ROS) production, and the levels of inflammatory cytokines and chemokines in PP-instilled mice (2.5 or 5 mg/kg) increased significantly compared to with those in the control. Histopathological analysis of the lung tissue of PP-stimulated mice revealed lung injuries, including the infiltration of inflammatory cells into the perivascular/parenchymal space, alveolar epithelial hyperplasia, and foamy macrophage aggregates. The in vitro study indicated that PP stimulation causes mitochondrial dysfunction including mitochondrial depolarization and decreased adenosine triphosphate (ATP) levels. PP stimulation led to cytotoxicity, ROS production, increase of inflammatory cytokines, and cell deaths in A549 cells. The results showed that PP stimulation increased the p-p38 and p-NF-κB protein levels both in vivo and in vitro, while p-ERK and p-JNK remained unchanged. Interestingly, the cytotoxicity that was induced by PP exposure was regulated by p38 and ROS inhibition in A549 cells. Conclusions: These results suggest that PP stimulation may contribute to inflammation pathogenesis via the p38 phosphorylation-mediated NF-κB pathway as a result of mitochondrial damage. [ABSTRACT FROM AUTHOR]

Background Adipokines such as leptin and adiponectin are associated with cognitive function. Although adiposity crucially affects adipokine levels, it remains unclear whether the relationship between adipokines and cognition is influenced by obesity. Methods We enrolled 171 participants and divided them into participants with obesity and without obesity to explore the effect of obesity on the relationship between adipokines and cognition. In addition to plasma levels of leptin and adiponectin, multidomain cognitive functions and brain structures were assessed using neuropsychological testing and magnetic resonance imaging. Association between levels of these adipokines and Alzheimer's disease (AD) was then assessed by logistic regression. Results We found that cognitive function was negatively associated with leptin levels and leptin-to-adiponectin ratio (LAR). Such correlations between leptin and cognitive domains were prominent in participants with obesity but were not observed in those without obesity. Leptin levels were associated with lower hippocampal volumes in participants with obesity. A significant interaction of leptin and obesity was found mostly in the medial temporal lobe. Both leptin and LAR were positively associated with insulin resistance and inflammation markers in all participants. Of note, LAR was associated with a higher risk of AD after adjusting for demographic variables, Apolipoprotein E genotype, and body mass index. Conclusions Obesity might be a factor that determines how adipokines affect brain structure and cognition. Leptin resistance might influence the relationship between adipokines and cognition. In addition, LAR rather than each adipokine levels alone may be a better indicator of AD risk in older adults with metabolic stress. [ABSTRACT FROM AUTHOR]