Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
Add more filters










Publication year range
1.
Aging Ment Health ; : 1-9, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940502

ABSTRACT

OBJECTIVES: This study investigates the correlation between self-reported sensory impairment, cognitive function, digital technology use, and social participation among older adults in South Korea. METHOD: Data from the 2020 National Survey of Older Koreans, comprising a nationally representative sample of 7849 individuals aged 65 years or older, were analyzed. A serial mediation analysis (Model = 6) was conducted using the PROCESS macro for SPSS. RESULTS: Following adjustment for covariates, cognitive function and digital technology use serially mediated the relationship between self-reported sensory impairment and social participation among older adults (B = -0.0020, SE = 0.0005, 95% confidence interval [CI] = [-0.0030, -0.0010]). Specifically, self-reported sensory impairment exhibited a negative correlation with cognitive function (B = -0.3277, SE = 0.0753, p < .001), which was positively associated with digital technology use (B = 0.0763, SE = 0.0056, p < .001), subsequently linking to enhanced social participation (B = 0.0784, SE = 0.0037, p < .001). CONCLUSION: Through cross-sectional analysis, this study confirms that self-reported sensory impairment in older adults may precede cognitive decline, hindering digital technology use and reducing social participation. Early diagnosis and treatment are crucial in preventing cognitive decline, while age-friendly digital devices may alleviate cognitive burden and promote social engagement.

2.
ACS Appl Mater Interfaces ; 16(13): 16622-16629, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38507524

ABSTRACT

Taste sensors using photonics, termed artificial photonic tongues, have emerged as a promising platform for intuitive taste discrimination. However, the need for complex binding protocols for each taste profile limits their applicability to a narrow range of taste molecules. Here, we introduce an intriguing "binding-free" approach to molecular taste sensing using plasmonics, eliminating the requirement for physical or chemical binding protocols. We develop a wafer-scale plasmonic metasurface constructed by coating metallic nanoparticles in a scalable manner onto a metallic mirror. This metasurface functions to detect molecular refractive indices and surface tensions via 2D projection optical images of an array of liquid droplets containing the taste molecules on top, which can immediately visualize and distinguish between the five basic tastes of molecules (including their mixtures) as well as other additional spicy and alcoholic tastes. We anticipate that this intuitive and rapid taste-sensing approach has the potential to establish a user-friendly and portable taste-sensing platform.

3.
Geriatr Gerontol Int ; 24 Suppl 1: 377-384, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38213083

ABSTRACT

AIM: The present study examined whether geographic location (i.e., rural vs. urban areas) moderated the relationship between social capital and COVID-19 preventive behaviors among older adults in South Korea. METHODS: Participants were a nationally representative sample of 61 075 Korean adults aged 65 years or older from the 2021 Community Health Survey by the Korea Disease Control and Prevention Agency. The moderation analysis was conducted with PROCESS. RESULTS: After adjusting for covariates, the moderation analysis showed a significant moderation effect of geographic location on the relationship between social capital and COVID-19 preventive behaviors among older adults in South Korea. Specifically, in urban areas, older adults with higher social capital were more likely to adhere to COVID-19 preventive behaviors. However, social capital negatively impacted older adults' COVID-19 preventive behaviors in rural areas. CONCLUSIONS: Findings suggest that social capital is not always helpful for maintaining COVID-19 preventive behaviors among older adults in South Korea. The social characteristics of geographic location need to be considered when initiating COVID-19 prevention campaigns in South Korea. Geriatr Gerontol Int 2024; 24: 377-384.


Subject(s)
COVID-19 , Social Capital , Humans , Aged , COVID-19/epidemiology , COVID-19/prevention & control , Surveys and Questionnaires , Public Health , Republic of Korea/epidemiology
4.
Adv Mater ; 36(16): e2313299, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38267396

ABSTRACT

Underwater adhesion processes in nature promise controllable assembly of functional nanoparticles for industrial mass production; However, their artificial strategies have faced challenges to uniformly transfer nanoparticles into a monolayer, particularly those below 100 nm in size, over large areas. Here a scalable "one-shot" self-limiting nanoparticle transfer technique is presented, enabling the efficient transport of nanoparticles from water in microscopic volumes to an entire 2-inch wafer in a remarkably short time of 10 seconds to reach near-maximal surface coverage (≈40%) in a 2D mono-layered fashion. Employing proton engineering in electrostatic assembly accelerates the diffusion of nanoparticles (over 50 µm2/s), resulting in a hundredfold faster coating speed than the previously reported results in the literature. This charge-sensitive process further enables "pick-and-place" nanoparticle patterning at the wafer scale, with large flexibility in surface materials, including flexible metal oxides and 3D-printed polymers. As a result, the fabrication of wafer-scale disordered plasmonic metasurfaces in seconds is successfully demonstrated. These metasurfaces exhibit consistent resonating colors across diverse material and geometrical platforms, showcasing their potential for applications in full-color painting and optical encryption devices.

5.
Front Public Health ; 11: 1215556, 2023.
Article in English | MEDLINE | ID: mdl-37841711

ABSTRACT

Objectives: The WHO emphasizes lifelong management of hearing diseases such as hearing loss and advocates for prevention. The Ear and Hearing Care Situation Analysis (EHCSA) tool was designed by the WHO for assessment and quality improvement of state-led management of hearing loss prevention and management programs. The purpose of this study was to use the EHCSA to assess the ear and hearing management program in Korea and to establish goals consistent with best practices for improving policies and services related to ear and hearing care. Methods: The EHCSA was used as a need assessment of the ear and hearing management services in the country. The EHCSA consists of two sections. Section 1 consists of 41 questions to evaluate health policies and support services. Section 2 consists of 203 questions to evaluate human resources and services of the ear and hearing management sector. Results: There are an estimated 800,000 people with hearing loss in Korea. Policies such as hearing aid support are in place, and outreach services such as free hearing tests are also being actively conducted. In all medical institutions, ear and hearing management treatment and medication prescriptions could be received without barriers. Workers in the fields of ear and hearing management, such as audiologists, language therapists, special education teachers, and sign language interpreters, are specialized and have well-established guidelines for training. Conclusion: Overall, the domestic ear and hearing management sector has confirmed that policies and services are well-prepared in comparison with advanced countries such as the United States, Iran, and China. The use of the EHCSA was functional in collecting data on the current state of domestic ear and hearing management policies and services in Korea, can be used for continuous quality improvement and expansion of medical services, and can be used as a reporting mechanism to the WHO.


Subject(s)
Hearing Loss , Hearing , Humans , United States , Hearing Loss/therapy , Hearing Tests , Republic of Korea , World Health Organization
6.
Ecotoxicol Environ Saf ; 265: 115469, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37742571

ABSTRACT

This study aimed to determine the toxicity standard and potential risks and effects of polyamide (PA) exposure on neurotoxicity, stress indicators, and immune responses in juvenile crucian carp Carassius carassius. Numerous microplastics (MPs) exists within aquatic environments, leading to diverse detrimental impacts on aquatic organisms. The C. carassius (mean weight, 23.7 ± 1.6 g; mean length, 13.9 ± 1.4 cm) were exposed to PA concentrations of 0, 4, 8, 16, 32 and 64 mg/L for 2 weeks. Among the neurotransmitters, the acetylcholinesterase (AChE) activity in the liver, gill, and intestine of C. carassius was significantly inhibited by PA exposure. Stress indicators such as cortisol and heat shock protein 70 (HSP70) in the liver, gill, and intestine of C. carassius were significantly increased, while immune responses to lysozyme and immunoglobulin M (IgM) were significantly decreased. Our study demonstrates the toxic effects of MP exposure on crucian carp's neurotoxicity, stress indicators, and immune responses.

8.
Sci Rep ; 13(1): 13538, 2023 Aug 19.
Article in English | MEDLINE | ID: mdl-37598285

ABSTRACT

Thermoplastic parts manufactured via fused filament fabrication (FFF) have limited strength and toughness compared to other types of polymer additive and subtractive manufacturing. Low strength results from poor interlayer adhesion, making FFF parts not suitable for most engineering applications. Post processing solutions, such as annealing, enable healing of these interlayers, thus approaching injection molded parts. Prior work demonstrated a core-shell polycarbonate (PC)-acrylonitrile butadiene styrene (ABS) structured dual material filament to provide thermo-structural stability during annealing of the ABS component; however, annealing was limited to relatively low temperatures (135 °C) and required long annealing times (72 h). In the current work, a PC copolymer with a higher glass transition temperature (173 °C) than conventional PC is processed along with an extrusion-grade ABS into a PC-ABS core-shell filament. This improved dual material filament was printed, annealed, and evaluated via Izod impact testing, ultimately yielding 83% of bulk annealed ABS z-direction strength at an accelerated annealing time (8 h) and higher annealing temperature (155-175 °C). A demonstration part is printed with the dual material filament and annealed at 155 °C for 8 h, resulting in excellent dimensional accuracy, and a ductile failure at 73% higher ultimate load compared to the brittle failure of an as-printed part. This work highlights that material selection and design of a bicomponent filament geometry can lead to parts printed with FFF, with increased strength compared to other post-processing techniques at reduced processing times.

9.
J Environ Manage ; 342: 118237, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37267764

ABSTRACT

This review describes the applicability of biofloc technology (BFT) to future aquaculture technologies. BFT is considered an innovative alternative for solving the problems of traditional aquaculture (for example, environmental pollution, high maintenance costs, and low productivity). Extensive research is being conducted to apply BFT to breed and raise many aquatic animal species. In BFT, maintaining an appropriate C:N ratio by adding a carbon source promotes the growth of microorganisms in water and maintains the aquaculture water quality through microbial processes such as nitrification. For the efficient use and sustainability of BFT, various factors such as total suspended solids, water turbidity, temperature, dissolved oxygen, pH, and salinity, stocking density, and light should be considered. The application of the transformative fourth industrial revolution technologies, Information and Communications Technology (ICT) and Internet of Things (IoT), to aquaculture can reduce the risk factors and manual interventions in aquaculture through automation and intelligence. The combination of ICT/IoT with BFT can enable real-time monitoring of the necessary elements of BFT farming using various sensors, which is expected to increase productivity by ensuring the growth and health of the organisms being reared.


Subject(s)
Aquaculture , Nitrification , Animals , Technology , Water Quality , Risk Factors
10.
Environ Toxicol Pharmacol ; 101: 104159, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37245611

ABSTRACT

Increased ocean temperature due to global warming affects the health and immunity of fish. In this study, juvenile Paralichthys olivaceus were exposed to high temperature after pre-heat (Acute: Acute heat shock at 32 °C, AH-S: Acquired heat shock at 28 °C & short recovery (2 h) and heat shock at 32 °C, AH-L: acquired heat shock at 28 °C and long recovery (2 days), AH-LS: acquired heat shock at 28 °C & long (2 days) + short (2 h) recovery). Heat shock after pre-heat significantly upregulated various immune-related genes, including interleukin 8 (IL-8), c-type lysozyme (c-lys), immunoglobulin M (IgM), Toll-like receptor 3 (tlr3), major histocompatibility complex IIα (mhcIIα) and cluster of differentiation 8α (cd8α) in the liver and brain of P. olivaceus. This study showed pre-exposure to high temperatures below the critical temperature can activate fish immunity and increase tolerance to high temperatures.


Subject(s)
Fish Diseases , Flounder , Animals , Flounder/genetics , Temperature , Water , Hot Temperature , Fishes/genetics , Gene Expression
11.
Sci Total Environ ; 877: 162874, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-36933717

ABSTRACT

Plastic waste discharged into the aquatic environment decomposes into microplastics (MP), which have toxic effects on fish species. Korean bullhead, Pseudobagrus fulvidraco is widely distributed in freshwater ecosystems in Korea, and it is important as an ecological indicator species to evaluate MP toxicity in Korea. In this study, the accumulation and physiological effects of juvenile P. fulvidraco exposed to microplastics (Polyethylene: PE-MPs with white surface and spherical shape) at control (0 mg/L), 100, 200, 5000 and 10,000 mg/L for 96 h were confirmed. Exposure to PE-MPs showed significant bioaccumulation of P. fulvidraco, and the accumulation profile was in the order of gut > gills > liver. Hematological parameters such as the red blood cell (RBC), hemoglobin (Hb) and hematocrit (Ht) were significantly decreased over 5000 mg/L In plasma components, calcium, magnesium and total protein were significantly decreased over 5000 mg/L, whereas glucose, cholesterol, aspartate aminotransferase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) were significantly increased over 5000 mg/L or at 10,000 mg/L In antioxidant responses, superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) were significantly increased over 5000 mg/L, whereas glutathione (GSH) was significantly decreased over 5000 mg/L. The results of this study suggest that acute exposure to PE-MPs induced all physiological changes in a concentration-dependent manner, and it affects the hematological parameters, plasma components and antioxidant response of juvenile P. fulvidraco after accumulation in specific tissues.


Subject(s)
Antioxidants , Water Pollutants, Chemical , Animals , Antioxidants/metabolism , Plastics/toxicity , Plastics/metabolism , Polyethylene/metabolism , Microplastics/toxicity , Microplastics/metabolism , Ecosystem , Fishes/metabolism , Glutathione/metabolism , Republic of Korea , Oxidative Stress , Water Pollutants, Chemical/toxicity
12.
Antioxidants (Basel) ; 12(2)2023 Feb 06.
Article in English | MEDLINE | ID: mdl-36829957

ABSTRACT

The application of biofloc to fish species has several advantages, including the enhancement of production by increasing growth performance and survival rate and the improvement of fish aquaculture physiological activity. There has been a recent increase in biofloc addition to fish culture, and this review examines changes this causes to the survival and growth rate of fish and its economic feasibility. Physiological activity and disease resistance of biofloc-fed fish is being extensively studied. The hematological parameters and antioxidant and immune responses of fish fed biofloc were reviewed in this study, as well as their disease resistance by testing them for major specific diseases. Standards for effectively applying biofloc to fish aquaculture are also suggested.

13.
Rev Sci Instrum ; 92(5): 053533, 2021 May 01.
Article in English | MEDLINE | ID: mdl-34243305

ABSTRACT

This paper describes an X-pinch device recently developed at Seoul National University (SNU). The SNU X-pinch device is designed and fabricated to accommodate various diagnostics as well as conduct versatile experiments. It is easy to change the capacitance of the pulse generator because the capacitor bank has a modular design without insulation oil or gas. This allows us to perform a variety of experiments with a wide capacitance range from 80 to 800 nF. The operating voltage of the SNU X-pinch device is controlled from 20 to 100 kV by adjusting the gas pressure inside a triggered spark-gap switch. Triggering of the spark-gap switch is synchronized with the operation of a pulsed laser to diagnose the X-pinch plasma at the proper time. A large vacuum chamber precisely machined from an aluminum mono-block is attached to the top of the pulse generator. It is designed to accommodate not only various X-pinch loads but also various diagnostic apparatus such as optical components. Initial experiments with the SNU X-pinch device have successfully generated x rays with wires of various materials and sizes. The device will be used not only to explore the dynamics of X-pinch plasmas but also as a test stand for diagnostics of high-energy-density plasmas.

15.
Appl Ergon ; 92: 103306, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33221499

ABSTRACT

It is clear that the cognitive resources invested in standing are greater than in sitting, but six of eight previous studies suggested that there is no difference in cognitive performance. This study investigated the effects of sitting and standing workstations on the physical workload and cognitive performance under variable cognitive demand conditions. Fifteen participants visited two times for testing sitting and standing workstations, and were asked to play two difficulty levels of Tetris game for 40 min while kinematic variables, CoP regularity, CoP SD, and cognitive performances were captured every 5 min. Results revealed a more neural posture in standing than in sitting, but using the standing workstation degraded attention and executive function. The CoP SD was 7 times greater in standing, but the CoP regularity was 1/4 in sitting, denoting greater attentional investment while engaged at the standing workstation.


Subject(s)
Standing Position , Workload , Biomechanical Phenomena , Cognition , Humans , Posture , Workplace
16.
Angew Chem Int Ed Engl ; 57(21): 6242-6246, 2018 05 22.
Article in English | MEDLINE | ID: mdl-29624849

ABSTRACT

A novel method for the catalytic asymmetric dearomatization by visible-light-activated [2+2] photocycloaddition with benzofurans and one example of a benzothiophene is reported, thereby providing chiral tricyclic structures with up to four stereocenters including quaternary stereocenters. The benzofurans and the benzothiophene are functionalized at the 2-position with a chelating N-acylpyrazole moiety which permits the coordination of a visible-light-activatable chiral-at-rhodium Lewis acid catalyst. Computational molecular modeling revealed the origin of the unusual regioselectivity and identified the heteroatom in the heterocycle to be key for the regiocontrol.

17.
Neuron ; 92(4): 902-915, 2016 Nov 23.
Article in English | MEDLINE | ID: mdl-27746132

ABSTRACT

Inhibitory interneurons are thought to play crucial roles in diverse brain functions. However, roles of different inhibitory interneuron subtypes in working memory remain unclear. We found distinct activity patterns and stimulation effects of two major interneuron subtypes, parvalbumin (PV)- and somatostatin (SOM)-expressing interneurons, in the medial prefrontal cortex of mice performing a spatial working memory task. PV interneurons showed weak target-dependent delay-period activity and were strongly inhibited by reward. By contrast, SOM interneurons showed strong target-dependent delay-period activity, and only a subtype of them was inhibited by reward. Furthermore, optogenetic stimulation of PV and SOM interneurons preferentially suppressed discharges of putative pyramidal cells and interneurons, respectively. These results indicate different contributions of PV and SOM interneurons to prefrontal cortical circuit dynamics underlying working memory.


Subject(s)
Behavior, Animal , Interneurons/physiology , Memory, Short-Term/physiology , Prefrontal Cortex/physiology , Pyramidal Cells/physiology , Reward , Animals , Gene Knock-In Techniques , Interneurons/metabolism , Mice , Optogenetics , Parvalbumins/genetics , Parvalbumins/metabolism , Somatostatin/genetics , Somatostatin/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...