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The strawberry growth and fruit yield of five Korean cultivars in the tunnel-type greenhouse predicted using their growth. The number of leaves, petiole length, leaf length and width, crown diameter, and the ratio of red and far-red (RFR) of the five Korean cultivars were measured during the cultivation period. The number of leaves of all cultivars exhibited a similar trend during this period; the plant and petiole length of ‘Maehyang’ were the longest, leaf length exhibited similar trends in all five cultivars except for ‘Jukhyang’, the leaf width of ‘Arihyang’, was the longest, and crown diameter of ‘Keumsil’ was the thickest. The leaf length, crown diameter, and RFR were associated with the fruit yield in the multiple linear regression. When a single model was used to predict the yield of all five cultivars, the correlation between expected yield and actual yield was r = 0.53. When cultivar-specific models were built for the prediction, the correlation increased to r = 0.77. The results indicated that the fruit yield of strawberry cultivars could be better predicted by considering cultivar-specific information, so it may be necessary to consider individual cultivars specifically rather than all cultivars simultaneously.

Vegetable crops production in the field and changes in physiological aspects of crops during the growing season may be affected by the increased temperatures associated with climate change. The objectives of this research were to evaluate the performance of an air temperature gradient using the computational fluid dynamics (CFD) technique and validation of performance throughout Kimchi cabbage growth and physiological responses to air temperature in a greenhouse temperature gradient (GTG). We simulated temperature differences with CFD in a semi-closed plastic tunnel, which is a GTG. The accuracy of CFD improved by vertical and horizontal temperature profiles was evaluated for the performances of a GTG. The growth of Kimchi cabbage was examined and validated using a temperature gradient within a GTG. Correlation coefficients of measured heights were 1.120, 0.597, and 0.459. Root mean square error was below 0.103, which means the CFD simulation values were highly accurate. The error analysis showed that it was possible to accurately predict temperature gradient changes within a GTG using CFD techniques. CFD results showed an average error of 0.597 °C compared to field monitoring results. The maximum temperature difference of the GTG was 5.7 °C, suggesting a well-controlled set point (6 °C difference between outside conditions and inside conditions of the GTG). On a cloudy day, the GTG set differential temperature (dT) was well maintained, while the accuracy of the GTG’s dT was degraded on sunny days because of interference by solar radiation. There was a significant difference in the growth, net photosynthetic rate, transpiration rate, and intercellular CO2 concentration along with temperature differences in the GTG. CFD can simulate temperature gradient distribution in a GTG and predict the temperature difference for equipment with different specifications. These facilities can be used in climate change-related studies, such as assessment of crop production area optimization, crop physiological response to temperature, vulnerability assessment of crop production under increasing temperatures, or extreme weather.

Advanced information and communication technologies have made data collection more efficient, and crop growth, yield, and environmental data of multiple farms can be used for various purposes. Using the publicly available database in South Korea, we investigated the correlation between the management of greenhouse environments and the pattern of strawberry yield during harvest seasons. Location-specific datasets were merged and processed, and mixed-effects models were applied to account for both observable greenhouse conditions and unobserved factors associated with farm locations. Instead of using averaged temperature and relative humidity inside greenhouses, we estimated the percent of time that air temperature has been between 15°C and 20°C, denoted by T%, and the percent of time that relative humidity has been between 0% and 50%, denoted by H%. The strawberry yield tends to reduce with respect to time during a harvest season, but the reduction rate is slower when the T% and H% are higher. This study provides empirical evidence for the practical significance of maintaining air temperature and relative humidity within an optimal range, and we conclude that growers can mitigate loss of production by the maintenance of air temperature and relatively humidity particularly during the later phase of a harvest season.

The texture of Kimchi cabbage was investigated by determining the hardness variation of midribs by leaf order and midrib position and analyzing the hardness characteristic by probe type. The objective of this research was the development of assessment methods for hardness of Kimchi cabbages in cropping types of summer season production. The hardness of the midrib of Kimchi cabbage leaves varied depending on the degree of development of the internal and external epidermis and the vascular tissues. The midrib hardness of Kimchi cabbage leaves did not differ significantly among cultivation types and tended to be lower toward the inner leaf. Using the Volodkevich bite jaws probe or blade set probe to measure the cutting force proved to be a suitable approach for examining the texture characteristic of Kimchi cabbage. The peak force of hardness in volodkevich bite jaw probe test the smallest distance and the second and third peak force intervals distance showed shortest among all the tested probes. In addition, hardness force tests with inside and outside results pattern was similar. When measuring the cutting force of midrib by these probes, it is preferable to measure from the outer epidermis to the inner epidermis of the leaf midrib, at 40–50 mm from the leaf stalk, on the 2nd to 6th outer leaves of Kimchi cabbage head formation.

As the number of international and domestic college students has increased, the importance of developing healthy lifestyles has been getting significant attention from college administrators. The current study was designed to determine if differences occur in exercise motivation between international and domestic college students. A total of 155 college students from a southwestern U.S. university completed the Exercise Motivations Inventory–2 through the university’s online active research system. Analyses indicated that international students possessed a higher motivation to exercise for revitalization, while domestic students were more motivated for a challenge, competition, and social recognition. The findings suggest that campus health professionals or wellness administrators may need to utilize different strategies to promote the health of international college students through exercise programs.

This study surveyed the information for development of mechanical transplanting of leafy vegetables. The priority production area of each crop, cultivation season, primary cultivar, transplanting method, and cultivation practice, in terms of furrow, ridge, and planting distance, were determined. The cultivation region, cultivation period, seedling, transplanting method, and size of furrow and ridge for cultivation of kimchi cabbage, cabbage, broccoli, and head lettuce were determined. These activities were carried out on commercial farms in the main producing region of leafy vegetables. Regarding kimchi cabbage, the standard sizes of furrow and ridge were 63 and 13 cm, respectively. The suitable wheel distance of the transplanting machine was 112–136 cm and the planting distance of kimchi cabbage was 65 × 45 cm. For cabbage transplanted in a single row, the furrow and ridge sizes were 76–90 and 13–15 cm, and the wheel distance and planting distance ranged from 152–180 and 76–90 × 45 cm, respectively. For broccoli and head lettuce, respectively, the furrow size range indicated 50–78 and 63–69 cm, with corresponding ridges of 10–20 and 12–13 cm, and the suggested wheel distances were 100–156 and 126–138 cm. In addition, the planting distance of broccoli and head lettuce represented 76–90 × 45 cm and 63–69 × 30 cm, respectively. Results indicated the optimal density for mechanized transplanting of various types of leafy vegetables and the information provided could be applied to develop the specification of the machine’s end effects.

This study investigated the effects of foliar applications, such as brassinosteroid (BR), methyl jasmonate (JA), salicylic acid (SA), and sodium nitroprusside (SNP), on the growth, yield, photosynthetic characteristics, and antioxidant enzyme activity of Kimchi cabbage (Brassica rapa L. ssp. pekinensis) exposed to heat stress. Kimchi cabbages were grown in extreme weather growth chambers under controlled conditions (air temperature, relative humidity, and solar radiation of the Daegwanryeong region, 37° 40′ N, 128° 32′ E). At 18 days after transplanting, Kimchi cabbages were treated with foliar application of biostimulants (vs. non-sprayed control) and exposed to heat stress (air temperature 30/25 °C) and mean daily air temperature under normal conditions (21.2 ± 1.6 °C day/night, respectively) for 5 days. The foliar application concentrations were 50, 100, and 200 nM BR; 50, 100, and 200 μM JA; 1, 2, and 4 mM SA; and 0.25, 0.50, and 1.00 mM SNP. At 38 days after foliar application, the shoot fresh weight of Kimchi cabbages treated with 200 nM BR was 2123 versus 1422 g plant−1 (control). The head weight and yield were the greatest with 2 mM SA treatment, which produced 3806 versus 2184 kg ha−1 (control). Heat stress induced a low photosynthetic rate in Kimchi cabbage, while foliar application of biostimulants enhanced photosynthesis recovery. During the 3 days after heat stress, catalase and peroxidase enzyme activities of Kimchi cabbage increased by 1.76- to 2.08-fold on average compared to the control. Results indicated that foliar application of biostimulants reduced physiological damage and enhanced the activity of the antioxidant enzymes, thereby improving heat stress tolerance in Kimchi cabbage.

Alternative splicing (AS) is a post-transcriptional regulatory mechanism that expands proteomic diversity. AS often occurs in the context of changing environmental conditions. Nevertheless, it rema...

The purpose of this study is to determine whether a 12-week exercise course influences obese African American older women’s health capabilities and life satisfaction levels. Participants, who passed an initial screening and pre-assessment, were asked to measure current health capabilities and life satisfaction levels both prior to, and following, the 12-week exercise training. Researchers found that improvement in health capabilities, although there were no significant differences following exercise training participation, while obese African American older women had significantly higher life satisfaction levels. The findings suggest that a 12-week exercise training can be beneficial to enhance obese African American older women’s health capabilities and life satisfaction levels. Professionals in the field of gerontology and exercise should provide the appropriate exercise trainings so that obese African American older women would be able to optimize their life satisfaction levels.

Background: Climate change is increasing the vulnerability of horticultural crop cultivation and production. It is urgent to study such extreme weather phenomena (heatwave, drought, etc.), and in particular, to evaluate crop productivity according to temperature change. For this purpose, the crop physiological response to temperature change in simulated weather conditions was studied. However, there is a limitation in artificial light wavelength, which requires experiments to be carried out in protected facilities or open fields. In this study, we simulated temperature differences with computational fluid dynamics (CFD) in tunnel-type greenhouses. They can create temperature gradients and improve the accuracy of CFD with vertically and horizontally measured temperature profiles. The growth and physiological response of Kimchi cabbage were examined and validated using a temperature gradient within a semi-closed plastic tunnel.Results: Correlation coefficients of measured heights were: 1.120, 0.597, and 0.459. Root mean square error was below 0.1025, which means the CFD simulation values were highly accurate. The error analysis showed that it was possible to accurately predict temperature gradients change within a semi-closed tunnel-type greenhouse using CFD techniques. CFD results showed an average error of 0.597°C compared to field monitoring results. The maximum temperature difference of GTG was 5.7°C, suggesting a well-controlled set point (6°C difference between outside conditions and inside conditions of GTG). In a cloudy day, the gradient temperature of GTG was well maintained by the set differential temperature (dT), which suggests that the set dT was not precisely and accurately performed in GTG of a sunny day. There was a significant difference in the growth, net photosynthetic rate, transpiration rate, and Ci concentration along with temperature differences in GTG. Conclusions: CFD can simulate temperature gradient distribution in a tunnel-type greenhouse and predict the temperature difference for equipment with different specifications. These facilities can be used in climate change-related studies, such as assessment of crop production area optimization, crop physiological response to temperature, vulnerability assessment of crop production under increasing temperatures, or extreme weather.

Adolescents enjoy their free time in different ways including solitary, passive, and active leisure activities. The current special circumstance, the COVID-19 pandemic, provides adolescents with more free time that individuals have to spend by themselves. However, there has been little research devoted to their participation in different leisure activities and its effect on adolescent self-esteem. This study examined current adolescents’ self-esteem levels and frequency of participation among solitary, passive, and active leisure activities and how participation in different types of leisure activities affects adolescent self-esteem. A total of 1759 adolescents self-reported 13 self-esteem items and the frequency of different types of leisure activities. The results revealed that 12 items of the self-esteem scale were higher scores than the average among adolescents in this sample. Adolescents spent significantly more time on solitary leisure activity (M = 4.85) than passive (M = 2.54) and active leisure activities (M = 3.51). The results of regression indicated that solitary activities (β = 0.068, p = 0.007) and sport/exercise (β = 0.267, p < 0.001) and hanging with friends (β = 0.113, p < 0.001) of active leisure activities were positively associated with adolescent self-esteem. The findings suggest that parents, teachers, and administrators should recognize and apply appropriate directions or programs to optimize adolescents’ self-esteem by developing suitable leisure activities. It could be helpful to provide other active leisure activities such as socialized clubs or extracurricular physical activities to improve their self-esteem.

Plasma lighting systems have been engineered to simulate sunlight. The objective of this study was to determine the effects of plasma lighting on tomato plant growth, photosynthetic characteristics, flowering rate, and physiological disorders. Tomato plants were grown in growth chambers at air temperatures of 25/23 °C (light/dark period), in a 16 h day−1 light period provided by four different light sources: 1 kW and 700 W sulfur plasma lights (1 SPL and 0.7 SPL), 1 kW indium bromide plasma light, and 700 W high pressure sodium lamp (0.7 HPS) as a control. The total dry weight and leaf area at 0.7 SPL were approximately 1.2 and 1.3 times greater, respectively, than that of 0.7 HPS at the 62 days after sowing (DAS). The maximum light assimilation rate was observed at 1 SPL at the 73 DAS. In addition, the light compensation and saturation points of the plants treated with plasma lighting were 98.5% higher compared with HPS. Those differences appeared to be related to more efficient light interception, provided by the SPL spectrum. The percentage of flowering at 0.7 SPL was 30.5%, which was higher than that at 0.7 HPS; however, there were some instances of severe blossom end rot. Results indicate that plasma lighting promotes tomato growth, flowering, and photosynthesis. Therefore, a plasma lighting system may be a valuable supplemental light source in a greenhouse or plant factory.

Aim Many older adults face limitations to participating in active leisure activities as a result of their physical constraints from aging. Passive leisure activities become alternative leisure activities for older adults as a result of limited physical capacity. The present study sought to determine whether there exists a difference in the frequency of participation in passive and active leisure activities, and the effect of participation in passive and active leisure activities on the life satisfaction level of old adults. Methods A total of 460 participants aged 60-95 years were randomly selected from 21 sites in the USA. The Life Satisfaction Index - Z and the Meaningful Activity Participation Assessment were analyzed to examine older adults' life satisfaction and frequency of active or passive activities. Results The results showed that participation in passive leisure activities, such reading, talking on the telephone and watching TV/listening to the radio, is more frequent among older adults (P = 0.000). The regression coefficient found that club/organization or volunteering (P = 0.008), homemaking/maintenance (P = 0.017) and traveling (P = 0.017) for active leisure activities were statistically significant predictors of Life Satisfaction Index - Z for older adults. Conclusions The current study shows that older adults spent much more times participating in passive leisure activities, such as radio/watching TV, talking on the phone and reading. The result also showed that active leisure activities, such as club/organization or volunteering, home making/maintenance and traveling, were significant predictors of life satisfaction for older adults controlling for covariates. The current study suggests marketing and programming plans to overcome the constraints that influence older adults' life satisfaction. Geriatr Gerontol Int 2018; 18: 380-386.

The objective of this study was to develop a growth model for grafted hot pepper seedlings as affected by air temperature and light intensity. After grafted union formation, the hot pepper seedlings were cultivated in various environmental factors in terms of four levels, mean daily air temperature (17, 22, 27, and 32 °C) and 3 levels of light intensity (150, 350, and 550 μmol·m−2·s−1). The growth traits were measured 0, 7, 14, 21, and 28 days after grafted union formation (DAGU). The plant height was improved, and development of leaves enhanced by higher air temperature. The number of leaves was greatest under the combination of the high temperature and high light intensity, resulting in 39.0/plant at 28 DAGU. The leaf area and dry weight showed 491.9 cm2/plant and 2.68 g/plant, respectively, at 28 DAGU under 32 °C air temperature and 550 μmol·m−2·s−1 light intensity. The changes of dry weight were rapidly increased under the higher air temperature and light intensity as followed by analysis of the growth curve. The beta distribution model was developed, and the relative growth rate (RGR) was simulated by the model, the maximum RGR was predicted at 0.116 g·g·d−1. The RGR showed 0.113, 0.127, and 0.109 g·g·d−1 at 10, 20, and 30 °C air temperature, respectively, and RGR was improved by 12% by increasing the air temperature by 10 °C, without going over 25 °C ADT. Results indicated that the developed growth model might be applied to optimal environmental control for maximized RGR of production of grafted hot pepper seedlings.

We evaluated the effects of interacting climate change factors on the morphology, growth, physiological responses, and yield of Kimchi cabbage leaves. Kimchi cabbage was cultivated under two climate change scenarios predicted by the Intergovernmental Panel on Climate Change; Representative Concentration Pathway (RCP) 4.5 and RCP 8.5. For the RCP 4.5 and RCP 8.5 treatments, the air temperatures were maintained 3.4 and 6.0°C above the prevailing control air temperatures and the CO2 concentrations were maintained at 540 and 940 µmol·mol -1, respectively, using newly developed extreme weather growth-chambers. Control plants were grown outside during the autumn. The RCP 4.5 and RCP 8.5 treatments led to tipburn disorders and rough leaves. The light compensation and saturation points of control plants were greater than those of the treatment plants. The maximum carboxylation rate, maximum rate of electron transport, and triose phosphate utilization rate of the RCP 8.5 treatment plants were significantly lower than those of the control. The control plants had the greatest yield among the studied plants, with a 65% reduction in yield observed in the RCP 4.5 treatment plants. The RCP scenarios retarded the growth and assimilation rates, and negatively affected leaf morphology, photosynthesis efficiency, and yield. These results suggest that climate change scenarios may have a profound impact on the cultivation of Kimchi cabbage and that effective mitigation strategies may be needed to ensure that this economically important crop has the necessary resilience under such climate change.

The ice plant (Mesembryanthemum crystallinum L.), a medicinal plant with well-known effects on retarding diabetes mellitus, is increasingly being produced in plant factories in Asia. The ice plant is a Crassulacean Acid Metabolism (CAM) plant, but performs C3 photosynthesis during the juvenile period. The objective of this study was to develop a photosynthetic model of ice plants growing under plant factory conditions. C3 photosynthesis was observed in juvenile plants in plant factory growth conditions and a conversion from C3 to CAM photosynthesis was observed under salt-stressed condition at an electrical conductivity (EC) of 6.0 dS·m-1. The light saturation and compensation points, determined by a regression analysis of C3 light curves for the ice plant leaves, were 609.4 and 53.2 μmol·m-2·s-1, respectively. The accuracy of the light response was compared between negative exponential and non-rectangular hyperbolic function models. The non-rectangular hyperbola was more accurate with complicated parameters while the negative exponential function was more practical with simple parameters in the light response curves. Measurement of net CO2 assimilation rate (A) and intercellular CO2 concentration (C i ) allowed construction of the A-Ci curve and regression analysis of this curve revealed the CO2 saturation and compensation points as 632.9 and 117.2 μmol·mol-1, respectively. A coupled photosynthetic model was developed for the simultaneous prediction of photosynthesis, stomatal conductance, transpiration, and temperature of the ice plant leaves. Sharkey’s regression method was used to determine the photosynthetic parameters of maximum carboxylation rate, the potential rate of electron transport, and the rate of triose phosphate utilization, which were 222.3, 234.9, and 13.0 μmol·m-2·s-1, respectively. The parameters of minimum stomatal conductance of water vapor at the light compensation point (b) and the empirical coefficient (m) for the sensitivity of stomatal conductance and relative humidity in the Ball, Woodrow and Berry model could be solved as b = 0.0487 and m = 0.0012 by linear regression analysis using the measured A-Ci values. Although the A-Ci curve of the negative exponential function had higher accuracy than the biochemical model, the coupled biochemical model could physiologically explain the photosynthesis of the ice plant leaves under plant factory conditions.

This study was carried out to determine the effects of vernalization, temperature, and soil water deficit (SD) on mesoph yll cells, growth, and yield of Chinese cabbage ( Brassica campestris L). The palisade parenchyma and spongy tissues of Chinese cabbage were observed under full irrigation and two weeks of SD treatment. These cells were severely collapsed by four weeks SD treatment. The SD treatment had the greatest influence on the growth of Chinese cabbage among the tested treatment factors (vernalization, temperature, and SD), growth significantly decreased by severe drought treatment (four weeks SD treatment). In addition, the relative growth rate, unit leaf rate, leaf area ratio, specific leaf area, and leaf weight ratio were si gnificantly affected by SD treatment; however, other individual factors and their combined treatments did not influence the analyzed growth parameters. The yield under vernalization after high temperature and full irrigation treatments was 3,056 kg/10 a, which was the greatest among all the tested treatments, while four-week SD treatment significantly reduced the yield. Head formation of Chinese cabbage was not altered under SD treatment, and vernalization treatments did not induce bolting. Our results indicat ed that collapsing mesophyll cells and reduced growth and yield were induced by SD treatment. Thus we suggest that optimal irrigation system should be install to avoid or overcome crippling drought conditions in the open field.Additional key words