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Introduction: Alzheimer's disease dementia (ADD) has now become a crucial concern for modern society as a result of increased life expectancy. However, it is often difficult for a majority of the population to afford expensive medical imaging tests for accurate diagnosis. As a solution, quantitative analysis of electroencephalography (EEG) that aids in a sufficient description of brain activities can be employed as a cost-effective, safe and objective diagnostic tool. In the presented research, we employed diverse QEEG features at both channel- and source-level to enhance the robustness of our previously established artificial intelligence (AI) model that distinguishes non-ADD (NADD) data from ADD data.Method 594 NADD and 137 ADD subjects’ EEG data were employed for the presented research. artifact-free data were obtained through the application of independent component analysis (ICA) and bad epoch rejection. Absolute and relative power spectra at 19 channels were first computed, followed by the estimation of source-level power spectra through standardized low-resolution brain electromagnetic tomography (s-LORETA). Through further feature engineering, functional brain networks were also obtained. The established channel-level features were transformed into images that spatially allocate absolute and relative spectral powers, which were utilized for the training of deep neural network structures. Moreover, source-level spectral powers and functional brain networks were adopted for the training of a tree-based machine learning algorithm. Prediction probabilities of the established classification models were ensembled through the voting method and returned the final classification result.Results The best classification accuracies of the absolute and relative channel-level spectral power image-based deep neural network models were 85.3% and 86.5% respectively. The tree-based model that has been trained with source-level features resulted in an accuracy of 87.7%. The accuracy of the ensemble model was 88.5%, which demonstrates the compensatory interaction among the models.Conclusions The promising classification results indicate the potential behind EEG-AI models for the analysis of neurodegenerative disorders. Through continuous analysis of several independent QEEG features of varying aspects, we may soon be able to more aptly diagnose several neurological disorders.

Objective: Converging evidence ranging from basic pathophysiology to epidemiological and clinical data has described a potential relationship between Parkinson’s disease (PD) and diabetes mellitus (DM). This study aimed to explore the effect of sugar control on the treatment of motor manifestations in PD. Methods: A total of 124 de novo PD patients were included in the study. The participants were classified into three groups, non-DM (n = 45), well-controlled (n = 41) and less-controlled DM (n = 38), based on the glycated hemoglobin (HbA1c) cut-off value of 7.0. Clinical parameters including Unified Parkinson’s Disease Rating Scale (UPDRS), Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA) were evaluated serial twice apart from 1 year. Results: The less-controlled DM group revealed significantly lesser improvement in UPDRS III (baseline to follow-up, 38.1 ± 9.6 to 29.9 ± 7.8; p < 0.001) than those of either non-DM (36.6 ± 8.9 to 22.9 ± 5.7) and well-controlled group (37.0 ± 8.8 to 24.0 ± 6.0) after standard PD treatment for 1 year. A higher HbA1c was correlated with a lesser decline of UPDRS III (b, 0.47; p < 0.001) among PD with DM population. Less-controlled DM effectively predicted a lesser decline of UPDRS III (b = + 5.426; p < 0.001). Conclusions: Our results demonstrated a potential negative effect of sub-optimally controlled blood sugar on treating motor manifestations of PD. Careful glucose management might be a beneficial strategy to improve the burden of motor symptoms in PD who have coexisting DM.

Highly conductive and flexible textile electrodes are developed via hot pressing of graphene and a textile. The pressure sensors based on the textile electrodes exhibit high sensitivity in a wide pressure range and outstanding durability.

To delineate the determinants of motor severity in vascular parkinsonism (VaP), we investigated the impact of regional white matter intensity (WMH) burden and co-morbidities on the motor score in the patients with VaP and normal dopamine transporter (DAT) imaging.In this multicenter, retrospective study, we reviewed the records of 63 patients diagnosed with VaP and normal DAT imaging on 18F-FP-CIT PET. Signal hyperintensities in deep white matter (DWMH), periventricular (PVH), basal ganglia (BG) regions, and infratentorial foci (ITF) were rated according to Scheltens scale, a semi-quantitative visual rating system. Motor severity was assessed with Unified Parkinson's Disease Rating Scale (UPDRS) motor score. Regional hyperintensity scores, patients' demographics, and co-morbidities such as type 2 diabetes, hypertension, dyslipidemia, and previous stroke history were used as starting variables, and stepwise regression analysis was performed to select independent predictors of motor severity.PVH (R = 0.33, p = 0.008) and DWMH score (R = 0.31, p = 0.015) correlated with the motor severity, while BG and ITF scores did not. Diabetic patients had significantly higher motor scores compared with non-diabetics (34.7 (13.0) vs. 27.5 (12.4), p = 0.008). Other factors such as sex, BMI, hypertension, dyslipidemia, and previous history of stroke did not impact motor severity. In multivariate analysis, PVH scores and diabetes significantly correlated with motor severity.PVH burden and diabetes were independent factors associated with motor severity in VaP with normal DAT imaging. Our results suggest that diabetes, along with white matter hyperintensities, may have a significant role in the development of motor symptoms in VaP.

To explore the effect of olfactory dysfunction on treatment of motor manifestations in Parkinson’s disease (PD). The current longitudinal retrospective cohort study consecutively recruited 108 de novo PD patients. Of whom 29 were normosmia and 79 were hyposmia, respectively, which was determined by the Korean Version of Sniffin’ Sticks Test II at the time of diagnosis. All the participants underwent serial clinical examinations including Unified Parkinson’s Disease Rating Scale (UPDRS), Mini-Mental State Examination, and Montreal Cognitive Assessment. The normosmic group demonstrated a significantly greater reduction of the UPDRS III score (30.3 ± 5.9 to 21.9 ± 5.1) than that of the hyposmic group (34.5 ± 9.3 to 28.5 ± 8.1) from baseline to 1-year later (p, 0.003; Bonferroni correction for p

Textile electronics are ideal for novel electronic devices owing to their flexibility, light weight, and wearability. In this work, wearable organic field-effect transistors (OFETs) with all-graphene electrodes, fabricated using hot pressing, are described. First, highly conductive and flexible electrodes consisting of a cotton textile substrate and electrochemically exfoliated graphene (EEG) were prepared via hot pressing. The EEG/textile electrodes exhibited a low sheet resistance of 1.3 Ω sq−1 and high flexibility; these were used as gate electrodes in the wearable OFETs. In addition, spray-coated EEG was also used as the source/drain (S/D) electrodes of the wearable OFETs, which recorded a sheet resistance of 14.8 Ω sq−1 after hot pressing. The wearable OFETs exhibited stable electrical performance, a field-effect mobility of 13.8 cm2 V−1 s−1, and an on–off current ratio of ~103 during 1000 cycles of bending. Consequently, the fabrication method for wearable transistors developed using textiles and hot-pressed graphene electrodes has potential applications in next-generation wearable devices.

As the control over radioactive species becomes critical for the contemporary human life, the development of functional materials for decontamination of radioactive substances has also become important. In this work, a three-dimensional (3D) porous carbon monolith functionalized with Prussian blue particles was prepared through removal of colloidal silica particles from exfoliated graphene/silica composite precursors. The colloidal silica particles with a narrow size distribution were used to act a role of hard template and provide a sufficient surface area that could accommodate potentially hazardous radioactive substances by adsorption. The unique surface and pore structure of the functionalized porous carbon monolith was examined using electron microscopy and energy-dispersive X-ray analysis (EDS). The effective incorporation of PB nanoparticles was confirmed using diverse instrumentations such as X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS). A nitrogen adsorption/desorption study showed that surface area and pore volume increased significantly compared with the starting precursor. Adsorption tests were performed with 133Cs ions to examine adsorption isotherms using both Langmuir and Freundlich isotherms. In addition, adsorption kinetics were also investigated and parameters were calculated. The functionalized porous carbon monolith showed a relatively higher adsorption capacity than that of pristine porous carbon monolith and the bulk PB to most radioactive ions such as 133Cs, 85Rb, 138Ba, 88Sr, 140Ce, and 205Tl. This material can be used for decontamination in expanded application fields.

Subjective cognitive complaints (SCCs) refer to self-perceived cognitive decline and are related to objective cognitive decline. SCCs in cognitively normal individuals are considered a preclinical sign of subsequent cognitive impairment due to Alzheimer’s disease, and SCCs in cognitively normal patients with Parkinson’s disease (PD) are also gaining attention. The aim of this review was to provide an overview of the current research on SCCs in cognitively normal patients with PD. A systematic search found a lack of consistency in the methodologies used to define and measure SCCs. Although the association between SCCs and objective cognitive performance in cognitively normal patients with PD is controversial, SCCs appear to be predictive of subsequent cognitive decline. These findings support the clinical value of SCCs in cognitively normal status in PD; however, further convincing evidence from biomarker studies is needed to provide a pathophysiological basis for these findings. Additionally, a consensus on the definition and assessment of SCCs is needed for further investigations.

We investigated whether telomere length (TL) reflecting physical rather than chronological aging is associated with disease progression in the different cognitive stages of Alzheimer's disease (AD). Study participants included 89 subjects with amyloid pathology (A+), determined through amyloid PET or cerebrospinal fluid analysis, including 26 cognitively unimpaired (CU A+) individuals, 28 subjects with mild cognitive impairment (MCI A+), and 35 subjects with AD dementia (ADD A+). As controls, 104 CU A- individuals were selected. The participants were evaluated annually over two years from baseline. Compared to the highest TL quartile group of MCI A+ participants, the lowest TL quartile group yielded 2-year differences of -9.438 (95% confidence interval [CI] = -14.567 ~ -4.309), -26.708 (-41.576 ~ -11.839), 3.198 (1.323 ~ 5.056), and 2.549 (0.527 ~ 4.571) on the Mini-Mental State Examination, Consortium to Establish a Registry for AD, Clinical Dementia Rating-Sum of Boxes, and Blessed Dementia Scale-Activities of Daily Living, respectively. With this group, the lowest TL quartile group had a significantly greater probability of progressing to ADD than the highest TL quartile group (hazard ratio = 13.16, 95% CI = 1.11 ~ 156.61). Telomere shortening may be associated with rapid cognitive decline and conversion to dementia in MCI A+.

Background Neurofilament light chain (NFL) level has been suggested as a blood-based biomarker for neurodegeneration in dementia. However, the association between baseline NFL levels and cognitive stage transition or cortical thickness is unclear. This study aimed to investigate whether baseline NFL levels are associated with cognitive stage transition or cortical thickness in mild cognitive impairment (MCI) and cognitively unimpaired (CU) participants. Methods This study analyzed data on participants from the independent validation cohort of the Korea Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer’s disease (KBASE-V) study. Among the participants of KBASE-V study, 53 MCI and 146 CU participants who were followed up for ≥ 2 years and had data on the serum NFL levels were eligible for inclusion in this study. Participants were classified into three groups according to baseline serum NFL levels of low, middle, or high. Results The Kaplan–Meier analysis showed association between the serum NFL tertiles and risk of cognitive stage transition in MCI (P = 0.002) and CU (P = 0.028) participants, analyzed separately. The same is true upon analysis of MCI and CU participants together (P < 0.001). In MCI participants, the highest serum NFL tertile and amyloid-beta positivity were independent predictors for cognitive stage transition after adjusting for covariates. For CU participants, only amyloid-beta positivity was identified to be an independent predictor. Conclusion The study shows that higher serum NFL tertile levels correlate with increased risk of cognitive stage transition in both MCI and CU participants. Serum NFL levels were negatively correlated with the mean cortical thickness of the whole-brain and specific brain regions.

The pathogenesis of isolated rapid eye movement sleep behavior disorders (iRBD) is poorly understood. The severity of RBD may reflect its pathogenesis.We compared motor function and non-motor symptoms (NMSs) between iRBD patients and healthy volunteers. We correlated motor function, NMSs, and striatal dopaminergic activity with RBD severity using video-polysomnography.Twenty-one iRBD patients and 17 controls participated. The Unified Parkinson's Disease Rating Scale part III scores were higher in patients compared to controls (iRBD is a multisystem neurodegenerative disorder, and gait abnormalities may be a disease characteristic, possibly related to the akinetic-rigid phenotype of Parkinson's disease. The correlation between pain/visuospatial dysfunction and RBD severity may be related to its pathogenesis.

The surface modification of recycled plastic film-based aggregates was investigated to improve the compatibility between the aggregates and a cement paste. Surface modification was performed using ultraviolet–ozone treatment (UV-O3), a silane coupling agent, O2 atmospheric pressure plasma, and acrylic binder coating methods. The surface properties of the modified aggregates were analyzed using a contact angle measuring instrument. The results revealed that for all surface modification methods, the contact angle decreased with an increase in the treatment time. According to the comparative evaluation results of the changes in the surface characteristics of the aggregates through various surface modification methods, the contact angle reduction rates were 58.9%, 51.4%, 25.5%, and 24.5% for the O2 atmospheric pressure plasma, the acrylic binder coating, the silane coupling agent, and the UV-O3 method, respectively. After 48 h, the contact angle had increased by 110.9%, 29.9%, 16.4%, and 5.9% for the O2 atmospheric pressure plasma, UV-O3, the silane coupling agent, and the acrylic binder coating, respectively. Namely, the surface modification using the acrylic binder coating method was found to be the most effective method in terms of the wettability increase effect and the long-term storage stability.

In this study we aimed to find the association between neuropsychological performance and body mass index (BMI) in patients with mild cognitive impairment (MCI). In addition, we investigated the effects of the apolipoprotein E (APOE) genotype in the relationship between the BMI and cognition in MCI.We enrolled a cohort of 3,038 subjects with MCI aged 65-90 from the Clinical Research Center for Dementia of South Korea and a dementia cohort of the Ewha Womans University Mokdong Hospital. MCI patients were classified into three subgroups according to the Asian standard of BMI. We compared cognitive performances between groups by one-way analysis of variance. To investigate the effects of the APOE genotype, we used multivariate linear regression models after adjusting for possible confounders.Even though normal BMI groups were younger, had more females, and had less comorbidities, the higher BMI groups had better cognitive functions. Among subjects with APOE ε4 carriers, there was a positive relationship between the BMI and the memory task alone.Our findings suggested that higher BMI in patients with MCI were associated with better cognitive performance. The effects of the APOE ε4 genotype in the associations between BMI and cognition were distinguishing. Therefore, according to physical status, APOE ε4 genotype-specific strategies in the assessments and treatments may be necessary in elderly patients with MCI.

A porous carbon foam (P-CF) with high porosity and large pore volume is developed to offer an efficient scaffold for radionuclides adsorption/decontamination. The three-dimensional (3D) porous structure can be easily formed by carbonization of petroleum pitch. During the heat treatment process, the volatile components from the petroleum pitch create highly interconnected pores without any templates, blowing and foaming agents. In addition, Prussian Blue (PB) nanoparticles are introduced onto the surface of the P-CF by a simple hydrothermal method. By combining the enhanced binding affinity to radionuclides with the increased porosity, the synthesized PB@P-CF exhibits the enhanced adsorption capacity for the Cesium ion (133Cs). This study provides a feasible way to utilize residual oil for preparing functionalized porous carbon-based adsorbents for the removal of radionuclides from aqueous solutions. The superior adsorption behaviors of the PB@P-CF make them promising candidates for radioactive materials adsorption/decontamination.

ImportancePolygenic risk scores (PRSs), which aggregate the genetic effects of single-nucleotide variants identified in genome-wide association studies (GWASs), can help distinguish individuals at a high genetic risk for Alzheimer disease (AD). However, genetic studies have predominantly focused on populations of European ancestry.ObjectiveTo evaluate the transferability of a PRS for AD in the Korean population using summary statistics from a prior GWAS of European populations.Design, Setting, and ParticipantsThis cohort study developed a PRS based on the summary statistics of a large-scale GWAS of a European population (the International Genomics of Alzheimer Project; 21 982 AD cases and 41 944 controls). This PRS was tested for an association with AD dementia and its related phenotypes in 1634 Korean individuals, who were recruited from 2013 to 2019. The association of a PRS based on a GWAS of a Japanese population (the National Center for Geriatrics and Gerontology; 3962 AD cases and 4074 controls) and a transancestry meta-analysis of European and Japanese GWASs was also evaluated. Data were analyzed from December 2020 to June 2021.Main Outcomes and MeasuresRisk of AD dementia, amnestic mild cognitive impairment (aMCI), earlier symptom onset, and amyloid β deposition (Aβ).ResultsA total of 1634 Korean patients (969 women [59.3%]), including 716 individuals (43.6%) with AD dementia, 222 (13.6%) with aMCI, and 699 (42.8%) cognitively unimpaired controls, were analyzed in this study. The mean (SD) age of the participants was 71.6 (9.0) years. Higher PRS was associated with a higher risk of AD dementia independent of APOE ɛ4 status in the Korean population (OR, 1.95; 95% CI, 1.40-2.72; P APOE ɛ4 status. The PRS based on a transancestry meta-analysis of data sets comprising 2 distinct ancestries showed a slightly improved accuracy.Conclusions and RelevanceIn this cohort study, a PRS derived from a European GWAS identified individuals at a high risk for AD dementia in the Korean population. These findings emphasize the transancestry transferability and clinical value of PRSs and suggest the importance of enriching diversity in genetic studies of AD.

The relationship between sleep parameters and longitudinal shortening of telomere length is unclear. This study aimed to investigate the relationship between sleep parameters and the shortening of leukocyte telomere length (LTL) over a year.Among the participants in the validation cohort of the Korea Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease, participants who measured both baseline and follow-up (two years later) of LTL were analyzed. They were dichotomized according to the degree of LTL attrition over two years. Clinical characteristics were compared between the faster and slower LTL shortening groups (cut-off points: -0.710 kbp,A total of 238 participants, aged 55-88 years, were included. Participants with faster LTL shortening had a shorter duration of sleep (Poor sleep quality, specifically short sleep duration, long sleep latency, and low sleep efficiency were associated with faster longitudinal shortening of LTL.

Background and purpose Two conversion scales between the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) have been validated for Korean patients with Parkinson's disease. The aim of the present study was to validate these conversion scales for all patients with cognitive impairments regardless of dementia subtype. Methods Medical records of 323 subjects who completed both MMSE and MoCA on the same day were retrospectively reviewed. Mean, median, and root mean squared error (RMSE) of the difference between true and equivalent MMSE scores were calculated. Intraclass correlation coefficients (ICCs) between true and equivalent MMSE scores were also calculated. The validity of MoCA-MMSE conversion scales was evaluated according to educational level (low educated: ≤6 years; high educated: ≥7 years) and subtypes of cognitive impairment. Results The difference between true and equivalent MMSE scores had a median value of 0, a mean value of 0.19 according to the van Steenoven scale, a mean value of 0.57 according to the Lawton scale, RMSE value of 2.2 according to the van Steenoven scale, and RMSE value of 0.42 according to the Lawton scale. Additionally, ICCs between true and equivalent MMSE scores were 0.92 and 0.90 on van Steenovan and Lawton conversion scales, respectively. These results were maintained in subgroup analyses. Conclusions Findings of the present study suggest that both van Steenovan and Lawton MoCA-MMSE conversion scales are applicable to transforming MoCA scores into MMSE scores in patients with cognitive impairments regardless of dementia subtype or educational level.

Background Genome-wide association studies (GWAS) have identified a number of genetic variants for Alzheimer’s disease (AD). However, most GWAS were conducted in individuals of European ancestry, and non-European populations are still underrepresented in genetic discovery efforts. Here, we performed GWAS to identify single nucleotide polymorphisms (SNPs) associated with amyloid β (Aβ) positivity using a large sample of Korean population. Methods One thousand four hundred seventy-four participants of Korean ancestry were recruited from multicenters in South Korea. Discovery dataset consisted of 1190 participants (383 with cognitively unimpaired [CU], 330 with amnestic mild cognitive impairment [aMCI], and 477 with AD dementia [ADD]) and replication dataset consisted of 284 participants (46 with CU, 167 with aMCI, and 71 with ADD). GWAS was conducted to identify SNPs associated with Aβ positivity (measured by amyloid positron emission tomography). Aβ prediction models were developed using the identified SNPs. Furthermore, bioinformatics analysis was conducted for the identified SNPs. Results In addition to APOE, we identified nine SNPs on chromosome 7, which were associated with a decreased risk of Aβ positivity at a genome-wide suggestive level. Of these nine SNPs, four novel SNPs (rs73375428, rs2903923, rs3828947, and rs11983537) were associated with a decreased risk of Aβ positivity (p p −8). Prediction performance for Aβ positivity increased when rs73375428 were incorporated (area under curve = 0.75; 95% CI = 0.74–0.76) in addition to clinical factors and APOE genotype. Cis-eQTL analysis demonstrated that the rs73375428 was associated with decreased expression levels of FGL2 in the brain. Conclusion The novel genetic variants associated with FGL2 decreased risk of Aβ positivity in the Korean population. This finding may provide a candidate therapeutic target for AD, highlighting the importance of genetic studies in diverse populations.

The ability to concentrate light into nanometric volumes enables access to an ultrastrong light-matter coupling regime. Graphene-based platforms are extremely appealing for achieving this goal. Indeed, this unique 2D material possesses a strong third-order nonlinear response, which, thanks to the intense near-fields associated with the excitation of surface plasmons, can be made substantial even at the single-photon level [1] , [2].

Subjective cognitive complaints (SCCs) are gaining attention as a self-perceived symptom for cognitive impairment in patients with Parkinson's disease (PD), but there are few suitable tools for assessing SCCs in PD. This study aimed to develop and validate a questionnaire for assessing SCCs in PD, called the Subjective Cognitive Complaints Questionnaire for Parkinson's Disease (SCCQ-PD).The SCCQ-PD consists of 12 yes/no questions on subjective cognitive function, and the questionnaire was completed by patients with PD (score-P) and their caregivers (score-C). The cognitive function of patients was examined using comprehensive neuropsychological tests.This study included 73 patients (38 cognitively normal, 25 with mild cognitive impairment [MCI], and 10 demented) and their caregivers. Score-P and score-C had excellent reliability (Kuder-Richardson formula 20 coefficients of 0.893 and 0.931, respectively), and the scores exhibited a strong intercorrelation. Both score-P and score-C were negatively correlated with cognitive performance, and both were excellent in discriminating demented patients from those with normal cognition or MCI (areas under the receiver operating characteristic curve of 0.83 and 0.88, respectively).The SCCQ-PD is a reliable tool for assessing SCCs in patients with PD. SCCs measured using the SCCQ-PD are correlated with objective cognitive decline and useful for discriminating demented patients from nondemented patients.

A polymer-based nanofiber membrane with a high specific surface area, high porosity and abundant adsorption sites is demonstrated for selective trapping of radionuclides. The Prussian blue (PB)/poly(methyl methacrylate) (PMMA) nanofiber composites were successfully prepared through a one-step, single-nozzle electrospinning method. Various analytical techniques were used to examine the physical and chemical properties of PB nanoparticles and electrospun nanofibers. It is possible to enhance binding affinity and selectivity to radionuclide targets by incorporation of the PB nanoparticles into the polymer matrix. It is noteworthy that the maximum 133Cs adsorption capacity of hte PB/PMMA nanofiber filter is approximately 28 times higher than that of bulk PB, and the removal efficiency is measured to be 95% at 1 ppm of 133Cs. In addition, adsorption kinetics shows that the PB/PMMA nanofiber has a homogenous surface for adsorption, and all sites on the surface have equal adsorption energies in terms of ion-exchange between cyano groups of the introduced PB nanoparticles and radionuclides.

Acoustic-graphene-plasmons (AGPs) are highly confined electromagnetic modes, which carry extreme momentum and low loss in the Mid-infrared (MIR) to Terahertz (THz) spectra. They are therefore enablers of extremely strong light-matter interactions at these long wavelengths. However, owing to their large momentum they are also challenging to excite and detect. Here, we demonstrate a new way to excite AGPs that are confined to nanometric-scale cavities directly from the far-field, via localized graphene-plasmon-magnetic-resonators (GPMRs). This approach enables the efficient excitation of single AGP cavities, which are able to confine MIR light to record-breaking ultra-small mode-volumes, which are over a billion times smaller than their free-space volume.

With the development of microelectronic devices having miniaturized and integrated electronic components, an efficient thermal management system with lightweight materials, which have outstanding thermal conductivity and processability, is becoming increasingly important. Recently, the use of polymer-based thermal management systems has attracted much interest due to the intrinsic excellent properties of the polymer, such as the high flexibility, low cost, electrical insulation, and excellent processability. However, most polymers possess low thermal conductivity, which limits the thermal management applications of them. To address the low thermal conduction of the polymer materials, many kinds of thermally conductive fillers have been studied, and the carbon-based polymer composite is regarded as one of the most promising materials for the thermal management of the electric and electronic devices. In addition, the next generation electronic devices require composite materials with various additional functions such as flexibility, low density, electrical insulation, and oriented heat conduction, as well as ultrahigh thermal conductivity. In this review, we introduce the latest papers on thermally conductive polymer composites based on carbon fillers with sophisticated structures to meet the above requirements. The topic of this review paper consists of the following four contents. First, we introduce the design of a continuous three-dimensional network structure of carbon fillers to reduce the thermal resistance between the filler–matrix interface and individual filler particles. Second, we discuss various methods of suppressing the electrical conductivity of carbon fillers in order to manufacture the polymer composites that meet both the electrical insulation and thermal conductivity. Third, we describe a strategy for the vertical alignment of carbon fillers to improve the through-plane thermal conductivity of the polymer composite. Finally, we briefly mention the durability of the thermal conductivity performance of the carbon-based composites. This review presents key technologies for a thermal management system of next-generation electronic devices.

Acoustic-graphene-plasmons (AGPs) are highly confined electromagnetic modes, which carry extreme momentum and low loss in the Mid-infrared (MIR) to Terahertz (THz) spectra. In this work [1], we demonstrate a new way to excite AGPs from the far-field, which are confined to nanometric-scale cavities, via localized graphene-plasmon-magnetic-resonators (GPMRs). This approach enables the efficient excitation of single AGP cavities, which are able to confine MIR light to record-breaking ultra-small mode-volumes that are ∼5·1010 times smaller than their free-space volume.

To explore the effect of olfactory dysfunction on treatment of motor manifestations in Parkinson's disease (PD). The current longitudinal retrospective cohort study consecutively recruited 108 de novo PD patients. Of whom 29 were normosmia and 79 were hyposmia, respectively, which was determined by the Korean Version of Sniffin' Sticks Test II at the time of diagnosis. All the participants underwent serial clinical examinations including Unified Parkinson's Disease Rating Scale (UPDRS), Mini-Mental State Examination, and Montreal Cognitive Assessment. The normosmic group demonstrated a significantly greater reduction of the UPDRS III score (30.3 ± 5.9 to 21.9 ± 5.1) than that of the hyposmic group (34.5 ± 9.3 to 28.5 ± 8.1) from baseline to 1-year later (p, 0.003; Bonferroni correction for p 0.0045). Of subdomains in UPDRS III, the axial domain revealed a remarkable decrease in the normosmic group. Further, the hyposmic group exhibited a higher development rate of freezing of gait (FOG) compared to the normosmic group (29/79 (36.7%) vs 2/29 (6.9%); p, 0.002) during 33.9 ± 7.7 months of the mean follow-up period. A Cox proportional hazards model demonstrated the hyposmia to be a significant risk factor for the future development of FOG (HR, 4.23; 95% CI 1.180-17.801; p, 0.05). Our data demonstrated the olfactory dysfunction to be a significant risk factor for the development of the FOG in PD. Hyposmic PD patients should be paid more careful attention to the occurrence of FOG in the clinical practice.

Background Alzheimer’s disease (AD) cerebrospinal fluid (CSF) biomarker cutoffs from immunoassays with low interlaboratory variability in diverse ethnic groups are necessary for their use in clinics and clinical trials. With lack of cutoffs from fully automated immunoassay platforms in diverse races, the aim of this study is to evaluate the clinical utility of CSF AD biomarkers from the Lumipulse fully automated immunoassay based on β-amyloid (Aβ) positron emission tomography (PET) status comparing with these from two manual immunoassays, in Koreans. Methods Among 331 Korean participants enrolled from a prospective, 3-year longitudinal observational study of the validation cohort of Korean Brain Aging Study for the Early Diagnosis and Prediction of AD, 139 (29 CN, 58 SCD, 29 MCI, and 23 AD) provided CSF and 271 underwent baseline amyloid PET (n = 128 with overlapping CSF and Aβ-PET, and 143 without CSFs). Three annual cognitive and neuropsychiatric function tests were conducted. Aβ42, Aβ40, total-tau, and phosphorylated-tau181 were measured by Lumipulse fully automated immunoassay and two manual immunoassays (INNO-BIA AlzBio3, INNOTEST). Clinical utility of CSF biomarker cutoffs, based on 128 participants with Aβ-PET, was evaluated. Results Cognitive and neuropsychological scores differed significantly among the groups, with descending performance among CN>SCD>MCI>AD. Biomarker levels among immunoassays were strongly intercorrelated. We determined the Aβ-PET status in a subgroup without CSF (n = 143), and then when we applied CSF biomarker cutoffs determined based on the Aβ-PET status, the CSF biomarkers (cutoffs of 642.1 pg/mL for Aβ42, 0.060 for Aβ42/Aβ40, 0.315 for t-tau/Aβ42, and 0.051 for p-tau/Aβ42, respectively) showed good agreement with Aβ-PET (overall AUC ranges of 0.840–0.898). Use of the Aβ-PET-based CSF cutoffs showed excellent diagnostic discrimination between AD and CN (Aβ42, Aβ42/Aβ40, t-tau/Aβ42, and p-tau/Aβ42) with overall AUC ranges of 0.876–0.952. During follow-up, participants with AD-like CSF signature determined by Aβ-PET-based cutoffs from Lumipulse showed rapid progression of cognitive decline in 139 subjects, after adjustment for potential confounders, compared with those with a normal CSF signature. Conclusion CSF AD biomarkers measured by different immunoassay platforms show strong intercorrelated agreement with Aβ-PET in Koreans. The Korean-specific Aβ-PET-based CSF biomarker cutoffs measured by the Lumipulse assay strongly predicts progression of cognitive decline. The clinical utility of CSF biomarkers from fully-automated immunoassay platforms should be evaluated in larger, more diverse cohorts.

International audience; Nonlinear nanophotonics leverages engineered nanostructures to funnel light into small volumes and intensify nonlinear optical processes with spectral and spatial control. Owing to its intrinsically large and electrically tunable nonlinear optical response, graphene is an especially promising nanomaterial for nonlinear optoelectronic applications. Here we report on exceptionally strong optical nonlinearities in graphene–insulator–metal heterostructures, which demonstrate an enhancement by three orders of magnitude in the third-harmonic signal compared with that of bare graphene. Furthermore, by increasing the graphene Fermi energy through an external gate voltage, we find that graphene plasmons mediate the optical nonlinearity and modify the third-harmonic signal. Our findings show that graphene–insulator–metal is a promising heterostructure for optically controlled and electrically tunable nano-optoelectronic components.

Background: Universal Alzheimer’s disease (AD) cerebrospinal fluid (CSF) biomarker cutoffs from immunoassays with low interlaboratory variability could improve diagnostic accuracy and help predict disease progression. To determine the diagnostic cutoffs of CSF AD biomarkers measured with three immunoassay platforms, including fully automated Lumipulse based on b-amyloid (Ab) positron emission tomography (PET) status, to determine diagnostic utility and clinical predictability.Methods: Three hundred thirty-one Korean participants were enrolled from a prospective, 3-year longitudinal observational study of the validation cohort of Korean Brain Aging Study for the Early Diagnosis and Prediction of AD: 71 cognitively normal (CN), 99 with subjective cognitive decline (SCD), 89 with mild cognitive impairment (MCI), and 72 with AD. Among these 331 participants, 139 (29, 58, 29, and 23 from each group, respectively) provided CSF and 271 underwent baseline amyloid PET. Three annual cognitive and neuropsychiatric function tests were conducted. Ab42, Ab40, total-tau and phosphorylated-tau181 were measured by Lumipulse fully automated immunoassay and two manual immunoassays (INNO-BIA AlzBio3, INNOTEST). Clinical utility of CSF biomarker cutoffs, based on 128 participants with Ab-PET, were evaluated.Results: Cognitive and neuropsychological scores differed significantly among the groups, with descending performance among CN > SCD > MCI > AD. Biomarker levels among immunoassays were strongly intercorrelated, and using the cutoffs for Ab-PET status with maximal AD diagnostic accuracy (n = 215), the levels showed excellent agreement with Ab-PET. Use of Ab-PET-based cutoffs for CSF biomarkers showed excellent diagnostic discrimination between AD and CN (Ab42, Ab42/Ab40, t-tau/Ab42 and p-tau/Ab42) with overall AUC ranges to discriminate AD and CN (0.876–0.952). During follow-up, participants with AD-like CSF signature determined by Ab-PET-based cutoffs from Lumipulse showed rapid progression of clinical scores, after adjustment for potential confounders, compared with those with a normal CSF signature.Conclusion: CSF AD biomarkers measured by different immunoassay platforms show strong intercorrelated agreement with Ab-PET. Ab-PET-based CSF biomarker cutoffs measured by immunoassays, including the Lumipulse, strongly predict progression of cognitive decline. The clinical utility of CSF biomarkers from fully automated immunoassay platforms should be evaluated in larger, more diverse cohorts.

Porous carbon electrodes that accumulate charges at the electrode/electrolyte interface have been extensively investigated for use as electrochemical capacitor (EC) electrodes because of their great attributes for driving high-performance energy storage. Here, we report porous carbon nanofibers (p-CNFs) for EC electrodes made by the formation of a composite of monodisperse silica nanoparticles and polyacrylonitrile (PAN), oxidation/carbonization of the composite, and then silica etching. The pore features are controlled by changing the weight ratio of PAN to silica nanoparticles. The electrochemical performances of p-CNF as an electrode are estimated by measuring cyclic voltammetry and galvanostatic charge/discharge. Particularly, the p-CNF electrode shows exceptional areal capacitance (13 mF cm&minus, 2 at a current of 0.5 mA cm&minus, 2), good rate-retention capability (~98% retention of low-current capacitance), and long-term cycle stability for at least 5000 charge/discharge cycles. Based on the results, we believe that this electrode has potential for use as high-performance EC electrodes.

Background Although amyloid PET of typical Alzheimer’s disease (AD) shows diffuse ß-amyloid (Aß) deposition, some patients show focal deposition. The clinical significance of this focal Aß is not well understood. We examined the clinical significance of focal Aß deposition in terms of cognition as well as Aß and tau cerebrospinal fluid (CSF) levels. We further evaluated the order of Aß accumulation by visual assessment. Methods We included 310 subjects (125 cognitively unimpaired, 125 mild cognitive impairment, and 60 AD dementia) from 9 referral centers. All patients underwent neuropsychological tests and 18F-flutemetamol (FMM) PET. Seventy-seven patients underwent CSF analysis. Each FMM scan was visually assessed in 10 regions (frontal, precuneus and posterior cingulate, lateral temporal, parietal, and striatum of each hemisphere) and was classified into three groups: No-FMM, Focal-FMM (FMM uptake in 1–9 regions), and Diffuse-FMM (FMM uptake in all 10 regions). Results 53/310 (17.1%) subjects were classified as Focal-FMM. The cognitive level of the Focal-FMM group was better than that of Diffuse-FMM group and worse than that of No-FMM group. Among the Focal-FMM group, those who had FMM uptake to a larger extent or in the striatum had worse cognitive levels. Compared to the Diffuse-FMM group, the Focal-FMM group had a less AD-like CSF profile (increased Aß42 and decreased t-tau, t-tau/Aß42). Among the Focal-FMM group, Aß deposition was most frequently observed in the frontal (62.3%) and least frequently observed in the striatum (43.4%) and temporal (39.6%) regions. Conclusions We suggest that focal Aß deposition is an intermediate stage between no Aß and diffuse Aß deposition. Furthermore, among patients with focal Aß deposition, those who have Aß to a larger extent and striatal involvement show clinical features close to diffuse Aß deposition. Further longitudinal studies are needed to evaluate the disease progression of patients with focal Aß deposition.

A higher levodopa dose is a strong risk factor for levodopa-induced dyskinesia (LID) in patients with Parkinson’s disease (PD). However, levodopa dose can change during long-term medication. We explored the relationship between levodopa dose and time to onset of LID using longitudinal multicenter data. Medical records of 150 patients who were diagnosed with de novo PD and treated with levodopa until onset of LID were collected. Levodopa dose were assessed as the dose at 6 months from levodopa initiation and rate of dose increase between 6 months and onset of LID. The groups with earlier LID onset had higher levodopa and levodopa-equivalent dose at the first 6 months of treatment and rapid increase in both levodopa and levodopa-equivalent dose. Multivariable linear regression models revealed that female sex, severe motor symptom at levodopa initiation, and higher rate of increase in both levodopa and levodopa-equivalent dose were significantly associated with early onset of LID. The present results demonstrated that rapid increase in levodopa dose or levodopa-equivalent dose is associated with early onset of LID.

Graphene-metal heterostructures can confine the optical field down to the atomic level. We report record enhancement of high-harmonic generation and demonstrate, for the first time, that plasmons can indeed affect the graphene nonlinear optical response.

The development of miniaturized and highly integrated microelectronic products has motivated the current importance of synthesizing heat-dissipation materials with high thermal conductivity and excellent electrical insulation. Although graphene is attractive for improving the thermal conductivity of polymers owing to its high aspect ratio and outstanding thermal conductivity, it significantly deteriorates electrical insulation capability, limiting its practical application in polymer composites for thermal management of electronics and systems. In this work, we used planetary ball milling to synthesize a hybrid powder Al@EEG consisting of electrochemically exfoliated graphene (EEG) and surface-passivated aluminum particles. This ball milling prevents contact between graphene sheets by uniformly dispersing EEG in Al matrices without the conventional surface modification or chemical treatment process of graphene, thereby imparting thermal conductivity and electrical insulation to the hybrid powder. The resulting epoxy composite, containing 35- wt% Al@EEG hybrid, retains an electrical resistance of 1014 Ω·cm or higher and a thermal conductivity of 1.43 W m−1 K−1, which is 499% higher than that of neat epoxy. The as-designed material points the way to polymer-based, thermally conductive, electrically insulating composites for various electronic components such as printed circuit boards and light-emitting diode driver cases.

We report the fabrication of organic field-effect transistors (OFETs) via spray coating of electrochemically exfoliated graphene (EEG) and conducting polymer hybrid as electrodes. To reduce the roughness and sheet resistance of the EEG electrodes, subsequent coating of conducting polymer (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)) and acid treatment was performed. After that, active channel layer was developed by spin coating of semiconducting poly(3-hexylthiophene) on the hybrid electrodes to define the bottom gate bottom contact configuration. The OFET devices with the EEG/PEDOT:PSS hybrid electrodes showed a reasonable electrical performances (field effect mobility = 0.15 cm2 V−1 s−1, on/off current ratio = 102, and threshold voltage = −1.57 V). Furthermore, the flexible OFET devices based on the Polydimethlsiloxane (PDMS) substrate and ion gel dielectric layer exhibited higher electrical performances (field effect mobility = 6.32 cm2 V−1 s−1, on/off current ratio = 103, and threshold voltage = −1.06 V) and excellent electrical stability until 1000 cycles of bending test, which means that the hybrid electrode is applicable to various organic electronic devices, such as flexible OFETs, supercapacitors, organic sensors, and actuators.

Background: Essential tremor is very common, but characterization is difficult because of its heterogeneity. Neuropathology is important to elucidate the characteristics of neurological disorders. However, pathological findings in essential tremor have been inconsistent among studies. Uric acid is a strong antioxidant and might be a biomarker in neurodegenerative process. We hypothesized that uric acid level would be reduced if essential tremor is a neurodegenerative disease. Our aim was to compare uric acid level between essential tremor patients and healthy individuals. Methods: This was a prospective, case-control, multicenter study with 92 essential tremor patients and 77 healthy subjects. For homogeneity, the essential tremor group was subdivided into two groups (hereditary and sporadic). Clinical and laboratory findings were compared among the essential tremor and healthy groups. Results: The demographic characteristics were comparable among the groups. The uric acid level was lower in the essential tremor group than in healthy subjects, but the difference did not reach statistical significance. There was a negative correlation between uric acid level and disease duration in the hereditary group (p = .046) and between uric acid level and age at onset in the sporadic group (p = .012). The mean values of total cholesterol were significantly lower in the sporadic group than in the other groups (p = .011). Total cholesterol was positively correlated with age at onset in the hereditary essential tremor group (p = .010). Conclusions: We did not find any evidence that uric acid levels suggested essential tremor is a neurodegenerative disease. However, further research with more patients might be needed given the negative correlations of disease duration and age at onset with uric acid level.