Jung-geun Lee

Photoplethysmography is used in various areas such as vital sign measurement, vascular characteristics analysis, and autonomic nervous system assessment. Photoplethysmographic signals are composed of ac and dc, but it is difficult to find research about the interaction of photoplethysmographic components. This study suggested a model equation combining two Lambert-Beer equations at the onset and peak points of photoplethysmography to evaluate ac characteristics, and verified the model equation t

The aim of this study was to evaluate the physiological and biochemical heat responses of grafted tomato (Solanum lycopersicum L.) seedlings and their changes during the post-stress recovery period. Heat-tolerant ‘Celebrity’ and heat-sensitive ‘Arkansas Traveler’ tomatoes were grafted onto a commercial ‘Maxifort’ rootstock, and transplants were grown in growth chambers for 14 days of heat treatment (38/30 °C, day/night) followed by 7 days of recovery (25/18 °C). Results showed significant differ

In this study, optimal position was approached by a search of a low-DC drift sensor attachment position for measuring photoplethysmography. DC and AC models were proposed by merging the Lambert-Beer equations at the conventional PPG onset and the peak into one equation. The position at which point the DC fluctuation is small and the AC component is large in the PPG was suggested. Among the lateral sides of four blood vessels, the dorsal, palmer, ulnar, and radial vessels region, the ulnar vessel

Heat stress is a major environmental constraint limiting tomato production. Tomato wild relatives Solanum pennellii and S. peruvianum are known for their drought tolerance but their heat stress responses have been less investigated, especially when used as rootstocks for grafting. This study aimed to evaluate the physiological and biochemical heat stress responses of tomato seedlings grafted onto a commercial ‘Maxifort’ and wild relative S. pennellii and S. peruvianum rootstocks. ‘Celebrity’ and

To determine the feasibility of reusing waste nutrient solution as an alternative fertilizer for vegetable production, we investigated the growth and shoot nutrient content of curled mallows (Malva verticillata L.) irrigated with tap water (pH 7.8, EC: 0.5 dS·m-1), nutrient solution (pH 5.7, EC: 2.7 dS·m-1) and waste nutrient solution (pH 5.0, EC: 2.2 dS·m-1 in average) collected from plant factories. Three waste nutrient solutions were applied in sequential orde

Salinity stress negatively affects plant growth but can also act as a eustressor, enhancing nutraceutical quality. Nanoparticles (NPs) have unique physical and chemical properties that can impact crop growth and abiotic stress responses in both beneficial and detrimental ways. This study investigated the potential of SiO 2 and ZnO NPs to alleviate salinity stress or enhance nutraceutical quality by synergizing with the eustressor effects of salinity in hydroponically grown lettuce. Two-week-old

Assuming that photons absorbed by a vessel do not have acute variations, DC component reflect the basal blood volume (or diameter) before blood pulsation. Vascular stiffness and reflection is influenced by changes in basal blood volume (or diameter). This paper describes analysis of the characteristic variations of vascular stiffness, according to relative variations in DC components of the PPG signal (25-75%). For quantitative analysis, we have used parameters that were proposed previously, ref

Humic substances (HS) and light-emitting diode (LED) light applications have shown beneficial effects on plant growth, nutrition, and yield in various vegetable crops. However, their carryover effects on fruit yield and quality, when applied to the growing media before transplanting, have not been widely explored in tomatoes. This study evaluated tomato transplant growth in response to the application of solid HS (1% v/v, control) and varying LED light qualities [10 blue (B):90 red (R), 50B:50R,

As a method of observing regeneration of damaged nerves, research is being conducted on analyzing the electric signals of nerve fibers that are damaged and regenerating by implanting a microelectrode array between those nerves. Microelectrode arrays possess high impedance and a unique phase characteristic according to their structural features,thus it requires a phase linearity test and an impedance test to prevent neural signal distortion.Therefore, this paper analyzes the features of microelec

Drought-tolerant tomato wild relatives Solanum pennellii and S. peruvianum show heat-tolerant responses, but their use as rootstocks to enhance thermotolerance has not been examined. This study investigated the effects of heat stress on tomato plants grafted onto commercial ‘Maxifort’ and wild relatives S. pennellii and S. peruvianum rootstocks in high tunnel, open-field and growth chamber experiments. Heat-tolerant ‘Celebrity’ and heat-sensitive ‘Arkansas Traveler’ cultivars were used as scions

Assuming that photons absorbed by a vessel do not have acute variations, DC component reflect the basal blood volume (or diameter) before blood pulsation. Vascular stiffness and reflection is influenced by changes in basal blood volume (or diameter). This paper describes analysis of the characteristic variations of vascular stiffness, according to relative variations in DC components of the PPG signal (25-75%). For quantitative analysis, we have used parameters that were proposed previously, ref

During the celebration of the 50th anniversary of the founding of the Korean Cancer Association, articles published in Cancer Research and Treatment from 2004 to 2023 were assessed based on the subject and design of each study. Based on this analysis, trends in domestic cancer research were inferred and directions were suggested for the future development of Cancer Research and Treatment.