• Journal of Animal Science and Technology
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• v.63 no.3
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• pp.531-544
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• 2021

Heat stress (HS) damages health and decreases performance variables in pigs, and if severe enough, causes mortality. However, metabolic changes under HS and recovery following HS are poorly understood. Therefore, this study was aimed to expose the essential mechanisms by which growing pigs respond to HS and the temporal pattern of plasma concentrations (PC) of amino acids (AAs) and metabolites. Crossbred male growing pigs were penned separately and allowed to adapt to thermal-neutral (TN) conditions (20℃ and 80% relative humidity; TN[-1D]). On the first day, all pigs were exposed to HS for 24 h (36℃ and 60% relative humidity), then to TN conditions for 5 days (TN[2D] to TN[5D]). All pigs had ad libitum access to water and 3 kg feed twice daily. Rectal temperature (RT) and feed intake (FI) were determined daily. HS pigs had higher RT (40.72℃) and lower (50%) FI than TN(-1D) pigs (p < 0.01). The PC of indispensable (threonine, valine, and methionine) and dispensable (cysteine and tyrosine) AAs were higher (p < 0.05) in HS than TN(-1D) pigs and remained increased during recovery time. Nonprotein α-aminobutyric acid and β-alanine concentrations were higher (p < 0.05) in HS than TN(-1D) pigs. The metabolite concentration of creatinine was higher (p < 0.01) under HS treatment than other treatments, but that of alanine and leucine remained increased (p < 0.05) through 5 d of recovery. In summary, some major differences were found in plasma AA profiles and metabolites between HS- and TN-condition pigs. This indicates that the HS pigs were forced to alter their metabolism, and these results provide information about mechanisms of acute HS responses relative to the recovery time.

• Journal of Forest and Environmental Science
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• v.28 no.1
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• pp.12-18
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• 2012

Like any other natural resources, forest flora may experience the extreme threat of elevated temperature and saline water submergence at different stages of their lives i.e. from germination to maturity due to climate change effects. The overall aim of the study was to measure the effect of higher temperatures along with saline water irrigation on survival and initial growth during seedling stage of Artocarpus chapalasha. The experiment was conducted in temperature- humidity-photoperiod regulated plant growth chamber during stipulated period to measure the growth performance of randomly selected seedlings. Within three different elevated temperatures viz. $30^{\circ}C$, $32^{\circ}C$ and $34^{\circ}C$, the seedlings were given three different saline conditions such as 0.5 g/L, 1.5 g/L and 2.5 g/L NaCl concentrations. Results found from the experiment was that, seedlings of Artocarpus chaplasha reared at different temperatures and saline water treatments showed stunted growth than reared at existing outdoor temperature ($26.31^{\circ}C$) irrigated with regular fresh water. Seedling growth at three different parameters such as height, collar diameter and number of leaves showed that with increasing temperature individuals respond negatively to increasing saline condition. The seedling's growth occurred at every day in height, collar diameter and leaf. However, growth rate reduced later during the observation. The combined effect of high salinity and higher elevated temperature results in seedling mortality. Therefore, Artocarpus chaplasha may not thrive at higher temperature and salinity intrusion at its early growing period in plantation and natural forest areas.

• The Korean Journal of Ecology
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• v.28 no.4
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• pp.231-235
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• 2005

Comparative water relations of Quercus acuta and Castanopsis cuspidata var, sieboldii were analyzed to assess their resistance to drought and low temperature stresses from early November to early December, As air temperature decreased both species showed an increased content of osmotically active solute concentration per unit of dry weight (NS/DW), leading to lower osmotic potential of both species at both full turgid state $(OP_{sat})$ and turgor loss point $(OP_{tlp})$ in December than November. No major difference in the ability to adjust osmotically was noticed between the two. This finding suggests that both species must respond adaptively under water and low temperature stresses to maintain turgor pressure in winter season. In addition to osmotic adjustment, a low bulk modulus of elasticity $(E_{max})$ shown in Castanopsis cuspidata var. sieboldii must also play an important role in turgor maintenance during winter season being apt to happen water and low temperature stresses in plants.

• Journal of Korean Orthopaedic Sports Medicine
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• v.9 no.2
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• pp.121-124
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• 2010

In athletes, repetitive low-energy impacts in plantar lesion lead often to tendinitis, stress fracture, or overuse syndrome. The major cause of heel pain in athletes is plantar fasciitis. And it is most often attributable to repetitive low energy impact, but the vast majority patients with heel pain achieve symptomatic relief with conservative treatment and return to full activities. Not commonly, Nerve entrapment may be occurred from repetitive low energy trauma in athletes, and is not as easily diagnosed. The authors observed a basketball player who complained of chronic heel pain that do not respond to conservative treatment, he had the lesions both plantar fasciitis and lateral plantar nerve entrapment. The authors described an unusual mechanism of entrapment of the lateral plantar nerve combined with a chronic plantar fasciitis in a basketball player and reported with review of literature.

• Knowledge Management Research
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• v.15 no.2
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• pp.89-106
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• 2014

As an empirical study on the psychological side effects of using Social Networking Services (SNS), this study aims to identify the reality of negative emotion of using SNS and to predict its consequences. To this end, a measurement tool was developed through literature review, in-depth interview with users and expert review to induce negative emotional factors that can arise while using SNS. An exploratory factor analysis was performed for a total of 24 measurement items, which then were divided into the following 6 factors: 'concern over privacy,' 'burden from undesired connection,' 'relative deprivation,' 'a sense of alienation,' 'concern over reputation' and 'negative feeling about simple relationship.' Also, the relationship between the 6 negative emotional factors and psychological dissonance was analyzed. The results indicate that all the factors, except relative deprivation and a sense of alienation, affect psychological dissonance. It was also found that psychological dissonance, which implies a conflicting condition from using SNS, significantly affects the behavior that possibly reduces and limits the use of SNS. In other words, the users who have experienced psychological dissonance respond passively by avoiding the use of SNS to resolve the dissonance. The results of this study provide the base for explaining the psychological side effects of using SNS, which have been understood at a phenomenal level, such as 'Facebook depression' or 'SNS stress.' In addition, this study is of significance as it helps understand the psychological mechanism by identifying the relationship between negative emotion and use behavior with the theory of cognitive dissonance.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.133-137
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• 2003

Cells respond to an accumulation of unfolded proteins in the endoplasmic reticulum (ER) by increasing transcription of genes encoding molecular chaperones and folding enzymes. The information is transmitted from the ER lumen to the nucleus by intracellular signaling pathway, called the unfolded protein response (UPR). In Saccharomyces cerevisiae, such induction is mediated by the cis-acting unfolded response element (UPRE) which has been thought to be recognized by Hac1p transcription factor. We cloned the ATFC gene showing similarity with Hac1p, and then examined to determine whether ATFC gene product specifically binds to UPRE by electrophoretic mobility shift assays. ATFC gene product displayed appreciable binding ${to ^{32}}P-labelled$ UPRE. Therefore, we concluded that ATFC represents a major component of the putative transcription factor responsible for the UPR leading to the induction of ER-localized stress proteins.

• Development and Reproduction
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• v.13 no.3
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• pp.199-205
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• 2009

HSP70 has widely been induced in in vivo hyperthermia conditions in various organisms to study gene regulation and recently neuroprotectve roles of the induced gene expression under varying conditions. We investigated different responses among various tissues in zebrafish under heat shock to evaluate whether spatial and temporal expression pattern of zebrafish (z) hsp70 in transcriptional and translational level under heat shock stress in different brain regions. Heat shock groups were given for 1 h at $37^{\circ}C$ after recovery by transferring the treated animals back to $28^{\circ}C$ for 1, 2 and 24 h for recovery, respectively. Control (CTRL) group was kept at $28^{\circ}C$. At the end of treatments, five animals were collected and used for isolation of total RNAs and peptides from the corresponding tissues. Expression of zhsp70 mRNA showed different patterns in recovery periods in the tissues including the brain, eye, intestines, muscles, heart and testis by RT-PCR. Unlike the RT-PCR analysis, Northern blot analysis demonstrated nearly 30-fold increase in zhsp70 at 1 h heat shock, suggesting that RT-PCR may not be appropriate in unmasking regulation of the time-dependent zhsp70 expression. In the experiment involving different brain regions, the cerebellum showed gradual activation at 1 h to R1h and decreases in R2h and R24h, while the medulla oblongata and optic tectum showed gradual increase at R1h and decrease at R24h, indicating that different brain tissues respond specifically to heat shock in inducing zhsp70 and recovering from the heat shock status. Western blot analysis also demonstrated that the intracellular levels of zHSP70 in three different brain regions including the cerebellum, medulla oblongata and optic tectum are differently induced and recovered to normal state. These results clearly demonstrate that different regions of the body and the brain tissues are responding differently to heat shock in the aspects of its level of expression and speed of recovery.

• Anxiety and mood
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• v.12 no.1
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• pp.1-6
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• 2016

Objective : This study was performed to confirm the hypothesis that the more one applies positive thinking, the less severe the symptoms of stress and the better the therapeutic responsein panic disorder and major depressive disorders. Methods : The study included 50 subjects with confirmed diagnoses of panic disorder or major depressive disorders. Positive thinking was assessed using Positive thinking scale. Beck Depression Inventory was used as a subjective measure for depression, and to ensure an objective measure for depression and anxiety, the Hamilton Depression and Hamilton Anxiety rating scales were implemented. Results : The positive thinking scale measured at the initial visit had shown a strong negative correlation with objective depression. Although patients with a high level of positive thinking had shown a tendency to respond better to the treatment, as compared with those with a lower level, the differences were not statistically significant. Conclusion : Positive thinking is likely to ameliorate major depressive disorder, panic disorder-induced depression, and anxiety. Nevertheless, it was not possible to confirm the effects of positive thinking on the patients' treatment responses.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.6
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• pp.233-237
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• 2007

Tropical natives (TROP) are capable of tolerating tropical heat because of their long-term adaptation to tropical environments. When exposed to heat stress, these natives tend to respond with lower sweat output, which is generally thought to be the result of heat acclimatization. The main objective of this study was to clarify central mechanisms inherent to suppressed thermal sweating in tropical natives (Malaysians) by comparing their sweating responses to those of temperate native (TEMP) (Koreans). This experiment was conducted in a thermoneutral climatic chamber ($24{\pm}0.5^{\circ}C,\;40{\pm}3%$ relative humidity). Heat loads were applied to each subject by the immersion of their lower legs in a hot water bath ($43^{\circ}C$ for 30 min). Sweat onset-time and sweat volume were compared between TROP and TEMP. The sweat onset-times on four selected points on the body ranged from 10.25 to 13.47 min in TEMP subjects, and from 16.24 to 17.83 min in TROP subjects (p<0.001). The local sweat volumes at the same sites ranged from 4.30 to $9.74 mg/cm^2$ in TEMP subjects, and from between 1.80 to $4.40mg/cm^2$ in TROP subjects (p<0.001). These results demonstrated a significant difference between TROP and TEMP subjects with regard to the manner in which they regulate their body temperatures when exposed to heat loads, and verified that long-term thermal adaptation blunts sweating sensitivities.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.6
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• pp.731-738
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• 2017

Twin-hulls frequently incur structural damage at connecting members between the hull and deck induced by pitching motions during voyages. so, reasonable reinforcement is necessary around vulnerable spots such as corner knuckle, the chine bottom and inner hull. Since guidelines for structural design are not clear, engineers often respond by reinforcing plate thickness, changing stiffener sizes and reducing frame spacing, etc. These members constitute about 85 % of the longitudinal dimensions of the ship, so it is necessary to locally reinforce certain points to minimize weight stress, and also solve construction cost problems while securing the freeboard margin. Therefore, we developed a new program by analyzing the structural design procedures for the twin car-ferries based on Korean Register of Shipping (KR) High Speed Craft Rules, identifying items that need to be added. In order to ensure the reliability of buckling estimations for procedures and design programs, we conducted a comparative study with other standards and confirmed that differences were minimal.