Purposes of Internet Use and Its Impacts on Physical and Psychological Health of Korean Older Adults

Older adults engage in online activities for various purposes. An increasing number of studies are establishing connections between the purposes of internet use and their impacts on health outcomes. This study aimed to examine how the purposes of internet use affect self-rated health and depressive symptoms among Korean older adults. A nationally representative survey of community-dwelling older adults in Korea was used in the analysis (n = 5094). Instrumental internet use (using the internet to access various forms of information, services, and other resources) in Korean older adults was as common as interpersonal communication use, and the purposes of internet use were mainly for information seeking for everyday needs and engaging in various activities for enjoyment. Internet use for interpersonal communication and instrumental purposes was significantly associated with depressive symptoms and self-rated health. Internet use for instrumental purposes had a greater impact on self-rated health (β = -0.186) and depressive symptoms (β = -0.160) compared with the impacts of interpersonal communication internet use on self-rated health (β = -0.101) and depressive symptoms (β = -0.047). The findings highlighted the necessity of designing interventions that take into account the different purposes of internet use for older adults in order to maximize its benefits, paying special emphasis for information seeking online.

Robustly Adherable Hierarchical Nanostructures via Self-Bonding and Self-Texturing of Aluminum Nitride for Applications in Highly Efficient Oil/Water Separation

The release of wastewater containing oily contaminants into water bodies and soils severely threatens the environment and human health. Although several conventional techniques are used in treating oil/water mixtures and emulsions, these methods are often expensive, time-consuming, and inefficient. Porous membranes or sponges are widely used in filtration or absorption, but their use is limited by their low separation efficiencies and secondary contamination. Recently, a novel technology that is designed to selectively separate oil from oil/water mixtures or emulsions by using materials with special wetting surfaces was developed. Superwetting surfaces may be used to selectively separate oils from emulsions. This approach enables the use of materials with relatively large pores, resulting in high throughput properties and efficiencies. In this study, a facile method is proposed for use in preparing a superhydrophobic-superoleophilic felt fabric for utilization in separating oil/water mixtures and emulsions. By hydrolyzing aluminum nitride nanopowders, the desired micro-/nanostructures may be successfully fabricated and firmly attached to a fabric surface without using a binder resin. This results in various materials with special wetting properties, regardless of their sizes and shapes and the successful separation of oil and water from oil/water mixtures and emulsions in harsh environments. This approach exhibits promise as a low-cost, scalable, and efficient method of separating oily wastewater, with the potential for use in wider industrial applications.

RF-SOI Low-Noise Amplifier Using RC Feedback and Series Inductive-Peaking Techniques for 5G New Radio Application

This paper presents a low-noise amplifier (LNA) with an integrated input and output matching network designed using RF-SOI technology. This LNA was designed with a resistive feedback topology and an inductive peaking technology to provide 600 MHz of bandwidth in the N79 band (4.4 GHz to 5.0 GHz). Generally, the resistive feedback structure used in broadband applications allows the input and output impedance to be made to satisfy the broadband conditions through low-impedance feedback. However, feedback impedance for excessive broadband characteristics can degrade the noise performance as a consequence. To achieve a better noise performance for a bandwidth of 600 MHz, the paper provided an optimized noise performance by selecting the feedback resistor value optimized for the N79 band. Additionally, an inductive peaking technique was applied to the designed low-noise amplifier to achieve a better optimized output matching network. The designed low-noise amplifier simulated a gain of 20.68 dB and 19.94 dB from 4.4 to 5.0 GHz, with noise figures of 1.57 dB and 1.73 dB, respectively. The input and output matching networks were also integrated, and the power consumption was designed to be 9.95 mA at a supply voltage of 1.2 V.

Tyrosinase Inhibition Antioxidant Effect and Cytotoxicity Studies of the Extracts of Cudrania tricuspidata Fruit Standardized in Chlorogenic Acid

In the present study, various extracts of C. tricuspidata fruit were prepared with varying ethanol contents and evaluated for their biomarker and biological properties. The 80% ethanolic extract showed the best tyrosinase inhibitory activity, while the 100% ethanolic extract showed the best total phenolics and flavonoids contents. The HPLC method was applied to analyze the chlorogenic acid in C. tricuspidata fruit extracts. The results suggest that the observed antioxidant and tyrosinase inhibitory activity of C. tricuspidata fruit extract could partially be attributed to the presence of marker compounds in the extract. In this study, we present an analytical method for standardization and optimization of C. tricuspidata fruit preparations. Further investigations are warranted to confirm the in vivo pharmacological activity of C. tricuspidata fruit extract and its active constituents and assess the safe use of the plant for the potential development of the extract as a skin depigmentation agent.