• Title/Summary/Keyword: physiological stress

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Physiological factors affecting rapid cold hardening of the beet armyworm, Spodoptera exigua(Hubner) (파밤나방(Spodoptera exigua(Hubner))의 내한성유기 관련인자 분석)

  • 송원례;김용균;조점래;김홍선;이정운
    • Korean journal of applied entomology
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    • v.36 no.3
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    • pp.249-255
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    • 1997
  • The sublethal temperature (5$^{\circ}$C for 2hr) led the fifth instar larvae of beet armyworm, Spodoprern exigucr (Hiibner), to increase cold tolerance to subzero lethal temperatures ( 'rapid cold hardening' ). The strength of rapid cold hardening was, however, varied among different populations which showed different cold tolerance in response to cold temperatures. To analyse the physiological factors affecting the rapid cold hardening, hernolymph osmolalities. supercooling points, glycerol contents, and cold stress proteins were measured by treating the fifth instar larvae with the sublethal low temperatures. The treated larvae showed increase of hemolymph osmolalities and glycerol contents. Changes of the osmolalities were greater in cold-hardy strains than in cold-susceptible strains. The sublethal temperature also induced them to express the cold-stress proteins (I0 - 20kD) in the hemolymph. but did not to change supercooling points.

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Soil salinity shifts the community structure and diversity of seed bacterial endophytes of salt-sensitive and tolerant rice cultivars

  • Walitang, Denver I.;Ahmed, Shamim;Jeon, Sunyoung;Pyo, Chaeeun;Sa, Tongmin
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.244-244
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    • 2017
  • Soil salinity due to accumulation of salts particularly sodium chloride affects agricultural lands and their vegetation. Generally, rice is a moderately sensitive plant with some cultivars with varying tolerance to salinity. Though there are physiological differences between salt-sensitive and salt-tolerant rice cultivars, both are still affected especially during high salinity and prolonged exposure. This also ultimately affects their indigenous bacterial endophytes particularly those that inhabit the rice seed endosphere. This study investigates the dynamic structure of seed bacterial endophytes of salt-sensitive and tolerant rice cultivars grown in different levels of soil salinity. Endophytic bacterial diversity was studied Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Results revealed a very interesting pattern of diversity and shifts in community structure of bacterial endophytes in the rice seeds. There is a general decrease in diversity for the salt-sensitive rice cultivar, IR29 as soil salinity increases. For the salt-tolerant cultivars, IC32 and IC37, diversity interestingly increased at moderate salinity then decreased at high soil salinity. The patterns of community structure is also strikingly different for the salt-sensitive and salt-tolerant rice cultivars. IR29 has a more even distribution of abundance, but under soil salinity, the community shifted where Curtobacterium, Pantoea, Flavobacterium and Microbacterium become the more dominant bacterial communities. For IC32 and IC37, the dominant bacterial groups under normal stress conditions were also the dominant bacterial groups during salt stress conditions. Their seed bacterial community is dominated by endophytes belonging to Microbacterium, Flavobacterium, Pantoea, Kosakonia and Enterobacter. Stenotrophomonas and Xanthomonas have not changed in terms of abundance under different salinity stress level in the salt-sensitive and salt-tolerant rice cultivars. This study showed that soil salinity greatly influenced the seed bacterial communities of rice seeds irrespective of their physiological tolerance to salinity.

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Efficacy of Cooling Vest for Auxiliary Body Cooling in Hot Environments (1) -Thermophysiological Response of Human Body in Local Cooling- (고온환경 하에서 착용하는 인체냉각 보조도구로서의 Cooling Vest 연구(1) -Local Cooling에 따른 인체의 온열생리학적 특성-)

  • Kwon, Oh Kyung;Kim, Jin-A;Kim, Tae Kyu
    • Fashion & Textile Research Journal
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    • v.2 no.3
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    • pp.265-271
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    • 2000
  • Heat stress results in fatigue, a decline in strength, alertness., and mental capacity. The problem is compounded when high humidity exists. To help relieve worker heat stress, many types of cooling units are marketed. While workers may experience some cooling, critical body core temperatures often continue to elevate. This study was designed to find the effects of three kinds of cooling vest with portable frozen gel strips on thermophysiological parameters and on temperature and humidity within clothing. The heart rate, rectal, and skin temperature as well as sweat rate and clothing microclimate were measured during 80 min in 5 healthy males. Inquiries were also made into the subjective rating thermal, humidity comfort, and fatigue sensations. The main findings in our experiments are as follows: (a) Physiological parameters such as rectal temperature was the lowest in garb A1, intermediate in garb A, and the highest in garb A2 throughout the experiment. And mean skin temperature was the lowest in garb A, intermediate in garb A1, and the highest in garb A2; (b) Temperature and humidity within clothing (back) were garb in Al, intermediate in garb A, and the highest in garb A2. But the temperature and humidity within clothing (chest) were garb in A, intermediate in garb A1, and the highest in garb A2; (c) Most participants (4 out of 5 persons) answered that they felt more comfortable and fatigueless in garb A1 than in garb A and A2. It is concluded that local cooling in garb A1 of the upper torso could physiological reduce the thermal strain in participants wearing cooling vest.

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Nutrition agenda during the era of the COVID-19 pandemic (COVID-19: "영양 아젠다")

  • Lee, Myoungsook
    • Journal of Nutrition and Health
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    • v.54 no.1
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    • pp.1-9
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    • 2021
  • This review describes the risk factors of the nutrition crisis in coronavirus disease 2019 (COVID-19) infections and suggests precision nutrition against long-term psychological and physiological stress. The mandatory quarantine and the social distancing are associated with an interruption of the lifestyle routine, resulting in psychological (i.e., boredom) and physiological stress. The stress with multiple causes and forms induces over-compensation of energy-dense food, such as sugary comfort food, and is defined as "food craving" because carbohydrates positively affect the psychological stability with serotonin secretion. The consumption of foods that promote an immune response against viral infections (vitamins & minerals; Cu, folate, Fe, Se, Zn, and Vit A, B6, B12, C, and D), reduce inflammatory cytokines (w-3 fatty acids, Vit D, fibers, and Mg), contain antioxidants (beta-carotene, Vit E, C, Se, and phenolics), and sleep-inducing proteins (serotonin, melatonin, and milk products) is essential. In addition, a reduced Vit D deficiency in winter due to less time spent outdoors under quarantine has been reported to be associated with viral infections. The case fatality rate of COVID-19 was significantly dependent on age, sex, race, and underlying health condition. To prevent malnutrition and cachexia in elderly people, weight loss and muscle wasting should be monitored and controlled. Inadequate protein intake, sedentary lifestyle, and inflammation are significant risk factors for sarcopenia. Moreover, relatively high intakes of fat or carbohydrate compared to low protein intake result in abdominal obesity, which is defined as "sarcopenic obesity." Keeping the food-safety guidelines of COVID-19, this study recommends the consumption of fresh and healthy foods and avoiding sugar, fat, salt, alcohol, and commercially frozen foods.

Effects of Horticultural Therapy on the Emotions and Stress Index of Trainees Entrusted to the Juvenile Classification Review Center

  • Ryu, Ja Yeong;Yun, Suk Young;Choi, Byung Jin
    • Journal of People, Plants, and Environment
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    • v.23 no.1
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    • pp.47-53
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    • 2020
  • This study conducted a horticultural therapy program for trainees entrusted to the Juvenile Classification Review Center in order to fill the educational gap while providing emotional stability during the one-month period of commissioned education. The effects of horticultural therapy were examined by the pretest and posttest changes of the emotional items such as anxiety, self-esteem, self-efficacy and stress index. As the research method, this study used the one-group pretest-posttest experimental design on 16 female trainees of commissioned education staying at the Juvenile Classification Review Center in the juvenile reformatory located in A city. The horticultural therapy program was carried out in four sessions: two on flower arrangement and two on planting. The scores before and after the horticultural therapy program were measured using the Revised Children's Manifest Anxiety Scale (RCMAS) to examine the effects of horticultural therapy on the reduction of anxiety for the adolescents staying in the Juvenile Classification Review Center. The results show that there was significant decrease in the mean of anxiety from 62.5 (SD = 6.8) to 57.6 (SD = 8.1) points after the program (p = .002). There was no significant change in self-esteem, which was 76.9 (SD = 11.2) before the horticultural therapy and 78.3 (SD = 8.7) after the therapy (p = .420). In self-efficacy, there was no significant change from 72.9 (SD = 10.9) before and 75.1 (SD = 11.0) after horticultural therapy (p = .178). In order to examine the physiological changes in such emotional functions, this study measured the stress index using the uBioMacpa as the tool. The result of the measurement showed that there was a significant change in the mean from 33.8 (SD = 2.3) before to 31.1 (SD = 2.2) after the horticultural therapy (p < .001).

Physiological Data Monitoring of Physical Exertion of Construction Workers Using Exoskeleton in Varied Temperatures

  • Ibrahim, Abdullahi;Okpala, Ifeanyi;Nnaji, Chukwuma
    • International conference on construction engineering and project management
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    • 2022.06a
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    • pp.1242-1242
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    • 2022
  • Annually, several construction workers fall ill, are injured, or die due to heat-related exposure. The prevalence of work-related heat illness may rise and become an issue for workers operating in temperate climates, given the increase in frequency and intensity of heatwaves in the US. An increase in temperature negatively impacts physical exertion levels and mental state, thereby increasing the potential of accidents on the job site. To reduce the impact of heat stress on workers, it is critical to develop and implement measures for monitoring physical exertion levels and mental state in hot conditions. For this, limited studies have evaluated the utility of wearable biosensors in measuring physical exertion and mental workload in hot conditions. In addition, most studies focus solely on male participants, with little to no reference to female workers who may be exposed to greater heat stress risk. Therefore, this study aims to develop a process for objective and continuous assessment of worker physical exertion and mental workload using wearable biosensors. Physiological data were collected from eight (four male and four female) participants performing a simulated drilling task at 92oF and about 50% humidity level. After removing signal artifacts from the data using multiple filtering processes, the data was compared to a perceived muscle exertion scale and mental workload scale. Results indicate that biosensors' features can effectively detect the change in worker physical and mental state in hot conditions. Therefore, wearable biosensors provide a feasible and effective opportunity to continuously assess worker physical exertion and mental workload.

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Ergonomic Design and Evaluation of Carrying Handles for Bag (포대 운반손잡이의 인간공학적 디자인 및 평가)

  • Jung, Hwa-S.;Park, Ah-Sung;Jung, Hyung-Shik
    • IE interfaces
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    • v.17 no.1
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    • pp.46-55
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    • 2004
  • Various characteristics of the object being lifted are known to affect the biomechanical, physiological, and psychophysical stresses. The object characteristics to be considered in the design process of lifting tasks are weight, shape, stiffness, and availability of handles and similar coupling devices. In this study, a prototype Polypropylene laminated bag with carrying handles was designed to decrease the physical stress of people who handle these bags. Physiological and psychophysical approaches as well as subjective ratings were applied to evaluate the effects of handles provided on the designed PP laminated bag. Statistical analysis showed that the VO2, heart rate, blood pressure, and Borg-RPE score for PP laminated fertilizer bag with carrying handles were significantly lower than those bags without handles. Moreover, Maximum Acceptable Lifting Endurance Time(MALET) measure, newly developed in this study, for bags with handles was significantly higher than those for bags without handles. It is thus recommended that the various types of bags and boxes be equipped with handles to reduce the musculoskeletal, physiological, psychophysical, and subjective perceived stresses.

The Effects of Sodium Chloride on the Physiological Characteristics of Listeria monocytogenes

  • Choi, Kyoung-Hee;Yoon, Yohan
    • Food Science of Animal Resources
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    • v.33 no.3
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    • pp.395-402
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    • 2013
  • Sodium chloride is used to improve various properties of processed meat products, e.g., taste, preservation, water binding capacity, texture, meat batter viscosity, safety, and flavor; however, many studies have shown that sodium chloride increases the resistance of many foodborne pathogens to heat and acid. Listeria monocytogenes has been isolated from various readyto- eat (RTE) meat and dairy products formulated with sodium chloride; therefore, the objective of this paper was to review the effects of sodium chloride on the physiological characteristics of L. monocytogenes. The exposure of L. monocytogenes to sodium chloride may increase biofilm formation on foods or food contact surfaces, virulence gene transcription, invasion of Caco-2 cells, and bacteriocin production, depending on L. monocytogenes strain and serotype as well as sodium chloride concentration. When L. monocytogenes cells were exposed to sodium chloride, their resistance to UV-C irradiation and freezing temperatures increased, but sodium chloride had no effect on their resistance to gamma irradiation. The morphological properties of L. monocytogenes, especially cell elongation and filament formation, also change in response to sodium chloride. These findings indicate that sodium chloride affects various physiological responses of L. monocytogenes and thus, the effect of sodium chloride on L. monocytogenes in RTE meat and dairy products needs to be considered with respect to food safety. Moreover, further studies of microbial risk assessment should be conducted to suggest an appropriate sodium chloride concentration in animal origin foods.

Physiological Responses of the Chicken Grunt Parapristipoma trilineatum to High Water Temperature Stress (사육수의 고수온 스트레스가 벤자리(Parapristipoma trilineatum)에 미치는 생리학적 영향)

  • Kim, Ki-Hyuk;Hong, Sung-Won;Moon, Hye-Na;Yeo, In-Kyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.51 no.6
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    • pp.714-719
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    • 2018
  • We investigated the effects of water temperature on physiological parameters in the chicken grunt Parapristipoma trilineatum. At high temperature, the aspartate aminotransferase (AST) and the alanine aminotransferase (ALT) levels were increased, suggesting that high temperature induced hepatic damage. In addition, total protein (TP) was high at high water temperatures, which were considered stressful in the breeding environment. At high water temperatures, triglycerides (TG) were low due to increased metabolic activity, which decreased the blood TG levels as TG were used as an energy source. There was no significant difference in the plasma osmolality or the blood ion concentrations with water temperature. In generally, lysozyme, a factor in innate immunity, increased with water temperature. However, lysozyme activity tended to decrease with increasing water temperature, but the difference was not significant. These results suggested that the decrease of biophylaxis at high temperature was affect the growth or survival of the population.

The Effectiveness of Stress Intervention Program for Hemodialysis Patients in Korea: A meta-analysis (국내 혈액투석환자의 스트레스 중재에 대한 효과 연구: 메타분석)

  • Bae, Yeon Hee;Lee, Ko Woon;Yeom, Hye Ah
    • Journal of the Korea Convergence Society
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    • v.11 no.2
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    • pp.361-373
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    • 2020
  • The purpose of this study was to meta-analyze the stress intervention program applied to patients with hemodialysis in Korea to confirm the effectiveness of the stress intervention program and to identify the characteristics and trends of the stress intervention method. A total of 10 studies were selected, and Quality Assessment tool was used MINORS and the data was analyzed using Comprehensive Meta Analysis Version 3.0 and Review manager version 5.3 The Quality Assessment score of studies was 21.2 points, and the effect size on the psychological stress was medium(g=-.72), and the effect size on cortisol of the physiological stress was also medium(g=-.52). Subgroup analysis showed that Music therapy and aromatherapy, individual providing, over 60 minutes per session and total of 10-20 times were more effectively reduced stress. Findings of this meta-analysis would be helpful for health professionals to provide more effective stress intervention program. Further randomized controlled trials of stress intervention program for patients with hemodialysis are more needed.