25 research outputs found
Progressive Fourier Neural Representation for Sequential Video Compilation
Neural Implicit Representation (NIR) has recently gained significant
attention due to its remarkable ability to encode complex and high-dimensional
data into representation space and easily reconstruct it through a trainable
mapping function. However, NIR methods assume a one-to-one mapping between the
target data and representation models regardless of data relevancy or
similarity. This results in poor generalization over multiple complex data and
limits their efficiency and scalability. Motivated by continual learning, this
work investigates how to accumulate and transfer neural implicit
representations for multiple complex video data over sequential encoding
sessions. To overcome the limitation of NIR, we propose a novel method,
Progressive Fourier Neural Representation (PFNR), that aims to find an adaptive
and compact sub-module in Fourier space to encode videos in each training
session. This sparsified neural encoding allows the neural network to hold free
weights, enabling an improved adaptation for future videos. In addition, when
learning a representation for a new video, PFNR transfers the representation of
previous videos with frozen weights. This design allows the model to
continuously accumulate high-quality neural representations for multiple videos
while ensuring lossless decoding that perfectly preserves the learned
representations for previous videos. We validate our PFNR method on the UVG8/17
and DAVIS50 video sequence benchmarks and achieve impressive performance gains
over strong continual learning baselines. The PFNR code is available at
https://github.com/ihaeyong/PFNR.git
Evidentiality-aware Retrieval for Overcoming Abstractiveness in Open-Domain Question Answering
The long-standing goal of dense retrievers in abtractive open-domain question
answering (ODQA) tasks is to learn to capture evidence passages among relevant
passages for any given query, such that the reader produce factually correct
outputs from evidence passages. One of the key challenge is the insufficient
amount of training data with the supervision of the answerability of the
passages. Recent studies rely on iterative pipelines to annotate answerability
using signals from the reader, but their high computational costs hamper
practical applications. In this paper, we instead focus on a data-centric
approach and propose Evidentiality-Aware Dense Passage Retrieval (EADPR), which
leverages synthetic distractor samples to learn to discriminate evidence
passages from distractors. We conduct extensive experiments to validate the
effectiveness of our proposed method on multiple abstractive ODQA tasks.Comment: Findings of EACL 202
High-intensity walking in midlife is associated with improved memory in physically capable older adults
Background
Little is known about the associations of midlife- and late life-initiated walking with Alzheimers disease (AD)-related cognitive decline in humans. We aimed to investigate whether high-intensity, prolonged, midlife-initiated walking is associated with changes in AD-related cognitive decline in physically capable older adults.
Methods
We studied 188 physically capable participants aged 65–90 years without dementia who underwent comprehensive clinical assessment, including of their walking modality (i.e., intensity, duration, midlife- or late life-onset), memory- or non-memory and total cognitive performance, and blood or nutritional biomarkers.
Results
The walking group showed better episodic memory (B = 2.852, SE = 1.214, β = 0.144, p = 0.020), but not non-memory cognition, than the non-walking group. High-intensity walking starting in midlife was significantly associated with better episodic memory (B = 9.360, SE = 3.314, β = 0.446, p = 0.005) compared to the non-walking group. In contrast, there were no differences in cognition according to walking duration, regardless of the onset time. The walking group also showed a similar association with overall cognition.
Conclusions
Among physically capable older adults without dementia, walking, particularly at high intensity and starting in midlife, is associated with improved episodic memory, an AD-related cognitive domain. Further attention should be paid to the role of walking in terms of AD prevention.This study was supported by grants from the Hallym University Research Fund (grant no. HURF-2020–56 and HURF-2022–13) and the Ministry of Science and ICT, Republic of Korea (grant no. NRF-2020R1G1A1099652). This study was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (grant no. RS-2023-00210820). The funding sources had no role in the study design, data collection, data analysis, data interpretation, writing of the manuscript, or decision to submit it for publication
Association between physical activity and episodic memory and the moderating effects of the apolipoprotein E ε4 allele and age
BackgroundAn abundance of evidence indicates that physical activity may protect against Alzheimer’s disease (AD) and related cognitive decline. However, little is known about the association between physical activity and AD-related cognitive decline according to age and the apolipoprotein E (APOE) ε4 allele (APOE4) as major risk factors. Therefore, we examined whether age and APOE4 status modulate the effects of physical activity on episodic memory as AD-related cognition in non-demented older adults.MethodsWe enrolled 196 adults aged between 65 and 90 years, with no dementia. All participants underwent comprehensive clinical assessments including physical activity evaluation and APOE genotyping. The AD-related cognitive domain was assessed by the episodic memory, as the earliest cognitive change in AD, and non-memory cognition for comparative purposes. Overall cognition was assessed by the total score (TS) of the Consortium to Establish a Registry for Alzheimer’s Disease neuropsychological battery.ResultsWe found significant physical activity × age and physical activity × APOE4 interaction effects on episodic memory. Subgroup analyses indicated that an association between physical activity and increased episodic memory was apparent only in subjects aged > 70 years, and in APOE4-positive subjects.ConclusionOur findings suggest that physical activity has beneficial effects on episodic memory, as an AD-related cognitive domain, in individuals aged > 70 years and in APOE4-positive individuals. Physicians should take age and APOE4 status account into when recommending physical activity to prevent AD-related cognitive decline
Implications of helplessness in depression: diagnosing mild cognitive impairment and analyzing its effects on cognitive decline in older adults
BackgroundThis study focuses on how elements of depression correlate with mild cognitive impairment (MCI) in older adults and the diagnostic efficacy of combining these components with the Mini-Mental State Examination (MMSE). The study also investigated the connection between individual depression components and overall cognitive function, as measured by the total score (TS) of the consortium to establish a registry for Alzheimer’s disease (AD) assessment battery.MethodsThe study included 196 nondemented adults aged 65 to 90 years at a university hospital and community. Comprehensive clinical assessments including the 30-item Geriatric Depression Scale (GDS) to measure components of depressive symptoms, TS, and blood nutritional biomarkers.ResultsOur stepwise logistic regression analysis highlighted the ‘helplessness item’ (odds ratio = 4.531, 95% CI = 2.218 to 9.258, p < 0.001) as a significant predictor for MCI diagnosis. Further, models incorporating ‘helplessness item + MMSE’ demonstrated markedly enhanced accuracy in diagnosing MCI, surpassing the performance of the MMSE used independently. Notably, the group characterized by helplessness showed a significant reduction in TS (B = −5.300, SE = 1.899, β = −0.162, p = 0.006), with this trend being particularly pronounced in individuals exhibiting lower levels of physical activity. Interestingly, this correlation did not manifest in participants with higher physical activity levels.ConclusionOur findings suggest that helplessness is highly effective in diagnosing MCI and is linked to a decrease in cognitive function. Therefore, when addressing MCI and AD-related cognitive decline, clinicians should consider helplessness
Ginseng intake and Alzheimer disease-specific cognition in older adults according to apolipoprotein ε4 allele status
BackgroundThe probable association among ginseng intake, Alzheimer’s disease (AD)-specific cognition, and apolipoprotein ε4 (APOE4) remains poorly investigated. Hence, we examined the association between ginseng intake and AD-specific cognition in older adults under the moderating effect of APOE4 status.MethodsThis study enrolled 160 adults aged 65–90 years without dementia. All participants underwent comprehensive dietary and clinical assessments including ginseng intake, AD-related cognition (i.e., delayed episodic memory, as the earliest cognitive change in AD), and non-memory cognition for comparative purposes.ResultsGinseng intake was associated with higher delayed episodic memory, but not non-memory cognition, compared to no ginseng intake. The interaction between ginseng intake and APOE4 status had a significant effect on delayed episodic memory. Subgroup analyses showed that ginseng intake was associated with higher delayed episodic memory in the APOE4-negative but not the APOE4-positive subgroup. The benefits of ginseng intake on delayed episodic memory were prominent in the high duration (≥5 years) and midlife onset (<65 years) groups.ConclusionOur study of older adults with no dementia suggests that ginseng intake (with high duration and midlife onset) had a beneficial effect on AD-specific cognitive decline, i.e., the delayed episodic memory. In addition, APOE4 status moderates the association between ginseng intake status and AD-specific cognitive decline
A Study on the Correlation between SLC25A26 Polymorphism and Gastritis and Gastric Ulcers in Koreans
Gastritis is an inflammation of the gastric mucosa and gastric ulcers are a break in the mucosa of the stomach lining. Past research on gastritis and gastric ulcers has been mainly conducted from the perspective that environmental factors are the primary cause of these gastric diseases. However, recently the importance of genetic factors has been emphasized due to current developments in genetic research. The SLC25A26 gene is believed to be associated with the accumulation of reactive oxygen species. Oxidative stress promotes an inflammatory response, which increases the production of free radicals and causes cellular damage, and these lead to the development of gastric diseases. In this study, the correlation between SLC25A26 and gastric diseases was analyzed. Polymorphisms in SLC25A26 were analyzed in 1,369 domestic gastric disease patients and 7,471 healthy controls. As a result, 11 single nucleotide polymorphisms (SNPs) (in the genotype) and 13 SNPs (in the imputation) showed statistical significance (P<0.05), and high relative risk of gastric diseases. Among them, the rs13874 allele of SLC25A26 showed a highly significant association with gastric diseases. In the genotype-based mRNA expression analysis, the minor allele (C) group showed increased mRNA expression and this could increase oxidative stress. In conclusion, SLC25A26 polymorphisms are associated with gastric diseases. These results may provide a basis for new guidelines for gastric disease management in the Korean population
The water extract of Korean Filipendula glaberrima Nakai attenuates acute colitis by suppressing inflammation via the MAPK and NF-κB pathways
Colitis means inflammation of colon. For the safe treatment of colitis, drugs derived from natural products are attracting attention as a new alternative therapy. Filipendula glaberrima Nakai (FG) is a perennial plant in Korea. It is known to contain a variety of flavonoids with anti-inflammatory properties. In this study, the anti-inflammatory effects of the water extract of FG (FGW) were measured in vitro and in vivo. In vitro, FGW decreased the production of inflammatory mediators and its genes in LPS-stimulated macrophages. In addition, FGW downregulated the phosphorylation of the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathway-related proteins. In vivo, administration of FGW improved the clinical symptoms of inflammation and repaired the damaged epithelium in dextran sulfate sodium (DSS)-induced colitis mice. In conclusion, FGW has anti-inflammatory activity in vitro and in vivo and this activity was mediated through reducing the phosphorylation of the MAPK and NF-κB pathways
Antioxidant and Anti-Inflammatory Activity of Filipendula glaberrima Nakai Ethanolic Extract and Its Chemical Composition
Many countries are endeavoring to strengthen the competitiveness of their biological resources by exploring and developing wild endemic plants. This study examined the effects of Filipendula glaberrima Nakai (FG) on the antioxidant and anti-inflammatory activity using an in vitro system. The bioactive components were also examined using chromatographic techniques. The ethanol extract of Filipendula glaberrima Nakai (FGE) exerted antioxidant activities in the radical scavenging and reducing power assays and had high amounts of total polyphenolic compounds. The qRT-PCR results suggested that FGE significantly downregulated the levels cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) 2, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 in LPS-stimulated RAW 264.7 cells. The FGE treatment also decreased the production of nitric oxide, TNF-α, and IL-6 significantly in a dose-dependent manner. In addition, FGE downregulated phosphorylation of MAPK and NF-κB signaling pathway-related proteins. The chromatographic and mass spectrometry results showed that FGE contained bioactive flavonoids such as (+)-catechin, miquelianin, quercitrin, and afzelin, which may be active compounds with antioxidant and anti-inflammatory activities. This study provides fundamental data on the anti-inflammatory activity of the FG and can serve as a good starting point for developing a novel natural anti-inflammatory agent using FGE-containing bioactive flavonoids
Effects of a pre-annealing treatment (PAT) on Cu2ZnSn(S,Se)(4) thin films prepared by rapid thermal processing (RTP) selenization
In this study, CZTSSe precursors (Se/Cu/SnS/ZnS) were deposited by sputtering and evaporation and then annealed without added chalcogen substances in an argon-filled atmospheric chamber using rapid thermal processing (RTP). A low-temperature pre-annealing treatment (PAT) was applied to induce a pre-reaction between Se and Cu/SnS/ZnS. It was found that the PAT leads to the formation of CuSe and Cu2-xSe and enhances Se incorporation during RTP chalcogenization. Scanning electron microscopy (SEM), X-ray diffractometry, Raman analysis and scanning transmission electron microscopy with energy dispersive spectroscopy (STEM-EDS) were applied to investigate the differences between the absorber with the PAT and the one without the PAT. Better morphologies on the surface and in the cross section were obtained for the CZTSSe absorber annealed using the PAT compared with the absorber annealed without the PAT. Both absorbers showed nearly pure kesterite phases in their upper regions, as confirmed by Raman analysis. However, STEM-EDS maps revealed that when the absorber was prepared without the PAT, Zn- and S-rich secondary phases and voids were easily formed near the back contact. The electrical characteristics and efficiencies of the CZTSSe thin films showed drastic changes; the CZTSSe solar cell without the PAT showed no diode response, but the cell with the PAT showed an efficiency of 6.77% with an open-circuit voltage (Voc), short-circuit current density (Jsc) and fill factor (FF) of 376 mV, 31.39 mA/cm2 and 57%, respectively. © 2015 Elsevier B.V. Allrightsreserved.FALS