• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.7
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• pp.2512-2531
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• 2014

We propose a new Distributed Denial of Service (DDoS) defense mechanism that protects http web servers from application-level DDoS attacks based on the two methodologies: whitelist-based admission control and busy period-based attack flow detection. The attack flow detection mechanism detects attach flows based on the symptom or stress at the server, since it is getting more difficult to identify bad flows only based on the incoming traffic patterns. The stress is measured by the time interval during which a given client makes the server busy, referred to as a client-induced server busy period (CSBP). We also need to protect the servers from a sudden surge of attack flows even before the malicious flows are identified by the attack flow detection mechanism. Thus, we use whitelist-based admission control mechanism additionally to control the load on the servers. We evaluate the performance of the proposed scheme via simulation and experiment. The simulation results show that our defense system can mitigate DDoS attacks effectively even under a large number of attack flows, on the order of thousands, and the experiment results show that our defense system deployed on a linux machine is sufficiently lightweight to handle packets arriving at a rate close to the link rate.

• Journal of Environmental Science International
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• v.12 no.11
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• pp.1189-1196
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• 2003

The effect of boron and aluminum on the development of adventitious roots was studied in sunflower cuttings. Three-day-old seedlings were de-rooted and grown in nutrient solutions with or without boron and supplemented with different concentrations (from 50 to 700 ${\mu}$M) of aluminum. The number and length of the adventitious roots and proline content in adventitious roots in response to insufficient boron and aluminum stress were determined periodically. The micronutrient boron caused the development of numerous roots in the lower parts of the hypocotyl. A dose-response of boron-induced rooting yielded an optimum concentration of 0.1 mM boron. In the absence of boron, in the majority of the adventitious roots, a significant inhibition was observed with or without aluminum, indicating that the most apparent symptom of boron deficiency is the cessation of root growth. Increasing concentrations of aluminum caused progressive inhibition of growth and rooting of the hypocotyls, and a parallel increase in proline levels of adventitious roots. Supplemental boron ameliorated the inhibitory effect of aluminum, suggesting that aluminum could inhibit root growth by inducing boron deficiency. Ascorbate added to medium in the absence of boron improved root growth and induced a significant decrease in proline levels. These findings suggest that adventitious root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

• Safety and Health at Work
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• v.14 no.3
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• pp.325-331
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• 2023

Background: Heat stress is a harmful physical hazard in many occupational settings. However, consequences of occupational heat exposure among workers in a sugarcane factory in Ethiopia are not well characterized. This study aimed to assess the level of occupational heat exposure-related symptoms and contributing factors. Methods: In this cross-sectional study, five workstations were selected for temperature measurement. Heat stress levels were measured using a wet-bulb globe temperature index meter. A stratified random sampling technique was used to select 1,524 participants. Heat-related symptoms were assessed using validated questionnaires. Results: The level of occupational heat exposure was 72.4% (95% CI: 70.2%-74.8%), while 71.6% (95% CI: 69.3%-74.9%) of participants experienced at least one symptom related to heat stress. The most common heat-related symptoms were swelling of hands and feet (78%), severe thirst (77.8%) and dry mouth (77.4%). The identified risk factors were a lack of reflective shields (AOR: 2.20, 95% CI: 1.53, 3.17), not-enclosed extreme heat sources (AOR: 1.76, 95% CI: 1.23, 2.51), a lack of access to shade (AOR: 9.62, 95% CI: 6.20, 14.92), and inappropriate protective clothing provision (AOR: 1.58, 95% CI: 1.27, 2.71). Conclusions: The burden of occupational heat exposure and heat-induced symptoms was high. Lack of reflective shields, the absence of enclosed extreme heat sources, a lack of access to shade, and inappropriate protective clothing provision were considerable attributes of heat stress. Therefore, the use of mechanical solutions to stop heat emissions at their sources and the key factors identified were areas for future intervention.

• Journal of Preventive Medicine and Public Health
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• v.29 no.2 s.53
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• pp.239-254
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• 1996

Health services on industrial noisy environment have been provided only for noise-induced hearing loss management until now. But gradually, modem diseases and death have come to be related to stress and mental health deeply, therefore noise-induced mental disorder, like a stress became very important. In this point, the purpose of this study was to analyze the relationship between noise exposure level in worksite and workers' stress symptoms. This study included a survey of 786 manual workers selected from 89 worksites in 21 factories in Puchon. The results were as follows: 1. For demographic characteristics, most of the workers were males(80.8%), the $20\sim29years$ old were 34.5% and those who graduated from high school were 65.3%. The workers whose monthly income ranged from 100,000 to 800,000 won were 37.5% and who have a religion were 47.9%. 2. For occupational characteristics, workers who had worked $1\sim5$ years in the factories were 33.0%. Those who were much for them workload were 43.9% and who worked more than 8 hours a day were 73.9%. Those who were disatisfied with their job and pay were 31.9% and 50.6%. The workers who responsed ventilation condition of their worksites were bad were 51.9% and the dissatisfed with working environment of their worksites were 45.9%. 3. Workers who were suffering from tinnitus were 53.3% and those who perceived hearing loss were 50.1%. Persons who reported they always wore earplugs at work were 35.4%. Those who felt earplugs bigger than their ears were 30.6% and those who experienced eardiseases caused by earplugs were 25.6%. 4. For the noise exposure level in worksite, workers who were exposed to $80\sim90dB$ were 30.3%, $90\sim100dB$ were 26.4% and $50\sim70dB$ were 19.2%. 5. Workers' stress symptoms were significantly related to marital status and their monthly income(p<0.05). Workers who were single and had lower monthly income showed higher PSI (Psychiatric Symptom Index) scores than those who were married and had higher monthly income. Higher PSI scores were also significantly related to $1\sim2$ days hight-work per week, much for them workload, dissatisfaction with their job, and bad relationship with their bosses and coworkers. 6. Higher PSI scores were significantly related to severe tinnitus and perceived hearing losso(p<0.001). Workers who felt the earplugs they use did not fit their ears showed significantly higher PSI scores(p<0.01). Workers who reported that they did not feel they need earplugs showed. significantly higher PSI scores (p<0.05). Increased experience of eardisease caused by earplugs that did not fit were also significantly related to higher PSI scores(p<0.01). 7. The higher noise exposure level in worksite from 80dB was, the more severe stress symptoms including PSI subparts were reported; Anxiety, Anger, Depression, and Cognitive disorder(p<0.001). 5. According to the results of stepwise multiple regression analysis, factors affecting workers' PSI scores were perceived hearing loss$(R^2=0.160)$, noise exposure level in worksite$(R^2=0.110)$, realtionship with coworkers, amount of workload, monthly income and relationship with bosses orderly and the total $R^2$ of this 6 factors was 0.371. 9. The most significant factors that have impact on manual workers' stress symptoms were perceived hearing loss and noise exposure level in worksite, especially noise exposure level in the worksite was the most affective factor on the depression symptom.

• Journal of Trauma and Injury
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• v.18 no.2
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• pp.175-178
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• 2005

Fat embolism syndrome is a collection of respiratory, neurological and cutaneous symptoms and signs associated with trauma and other disparate surgical and medical conditions. The incidence of clinical syndrome is low while the embolization of marrow fat appears to be an almost inevitable consequence of long bone fractures. The pathogenesis is a subject of conjecture and controversy. There are two theories which have gained acceptance(mechanical theory, biochemical theory). Onset of symptom is usually within 12 to 72 hours, but may manifest as early as 6 hours to as late as 10 days. The classic triad of fat embolism syndrome involves pulmonary changes, cerebral dysfunction and petechial rash. The cornerstone of treatment is preventing the stress response, hypovolemia and hypoxia and operative stabilization of fractures. Corticosteroid are the only drugs which have repeatedly shown a positive effect on the prevention and treatment of fat embolism syndrome. We report a case of post-traumatic fat embolism syndrome with severe cerebral involvement without respiratory distress. A 55 years old female had a traffic accident. She sustained pelvic bone fracture and both humerus fracture. Approximately 4 hours after the accident, mental status change developed without a focal neurologic deficits. She had no respiratory symptom and sign. Her brain MRI showed multiple cerebral fat embolism lesion. The patients received supportive treatment with corticosteroid, albumin. Her neurologic status stabilized over several days. After orthopedic surgery, she was discharged 62 days after admission.

• The Plant Pathology Journal
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• v.32 no.4
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• pp.300-310
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• 2016

Pathogen infection in plants induces complex responses ranging from gene expression to metabolic processes in infected plants. In spite of many studies on biotic stress-related changes in host plants, little is known about the metabolic and phenotypic responses of the host plants to Pseudomonas cichorii infection based on image-based analysis. To investigate alterations in tomato plants according to disease severity, we inoculated plants with different cell densities of P. cichorii using dipping and syringe infiltration methods. High-dose inocula (${\geq}10^6cfu/ml$) induced evident necrotic lesions within one day that corresponded to bacterial growth in the infected tissues. Among the chlorophyll fluorescence parameters analyzed, changes in quantum yield of PSII (${\Phi}PSII$) and non-photochemical quenching (NPQ) preceded the appearance of visible symptoms, but maximum quantum efficiency of PSII ($F_v/F_m$) was altered well after symptom development. Visible/near infrared and chlorophyll fluorescence hyperspectral images detected changes before symptom appearance at low-density inoculation. The results of this study indicate that the P. cichorii infection severity can be detected by chlorophyll fluorescence assay and hyperspectral images prior to the onset of visible symptoms, indicating the feasibility of early detection of diseases. However, to detect disease development by hyperspectral imaging, more detailed protocols and analyses are necessary. Taken together, change in chlorophyll fluorescence is a good parameter for early detection of P. cichorii infection in tomato plants. In addition, image-based visualization of infection severity before visual damage appearance will contribute to effective management of plant diseases.

• Journal of Preventive Medicine and Public Health
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• v.30 no.4 s.59
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• pp.791-804
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• 1997

Irritable bowel syndrome(IBS) is one of the common health problem that has been considered as stress-induced. This study was conducted to investigate the relationship between life style and the level of stress and IBS by structured questionnaire which included questions on life style, the self-esteemed gastrointestinal symptoms, and Psychosocial Well-being Index(PWI). Subjects were 1,498 male white collars who get the regular health check and participated in survey at Inje University Health Promotion Center from January to ,December, 1996. The overall prevalence of IBS was 37.5%(561 cases), and the level of stress by PWI score was higher in IBS group$(41.8{\pm}14.2)$ than symptom-free group$(34.6{\pm}12.6)$. As the result of comparison between the two groups, heavier smoking (adjusted O.R=2.48, 95% C.I 1.81-3.41), longer daily working time (adjusted O.R=5.19, 95% C.I 3.59-7.56), stimulatory food materials-mainly hot or salty (adjusted O.R=1.87, 95% C.I 1.44-2.45), higher body mass index (adjusted O.R=1.80, 95% C.I 1.27-2.57), and higher level of stress (adjusted O.R=2.81, 95% C.I 1.80-4.43) were estimated as risk factors of IBS. On the contrary, 6-8 hours sleeping per day (adjusted O.R=0.38 95% C.I 0.21-0.70), 3-4 times exercise per week (adjusted O.R=0.57 95% C.I 0.39-0.83), and tenure more than 20 years (adjusted O.R=0.25 95% C.I 0.16-0.35) were considered as protective factors to IBS. In summary, the assessment of the stress level might be placed in the first priority to control IBS, at least by some degree, which suggested that IBS could be controlled by avoiding such risk factors and by encouraging such protective factors.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1065-1072
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• 2004

Depression is associated with a dysfunctional serotonin (5-hydroxytryptamine; 5-HT) system. More recently, several lines of evidence suggest that an important factor in the development of depression may be a deficit in the function and expression of $5-HT_{1A}$ receptors. The present study assessed if Nelumbinis Semen (N. s.) had an anti-depression effect through reversing a decrease in $5-HT_{1A}$receptor binding in rats with depression-like symptoms induced by chronic mild stress. Using a $5-HT_{1A}$ receptor binding assay, with a specific $5-HT_{1A}$receptor agonist, 8- OH-DPAT (8-hydroxy-2-(di-n-propylamino) tetralin), the mechanism of the anti-depression effect of N. s. on rats was investigated, and the effects compared with two well-known antidepressants, Hyperium Perforatum (St. Johns Wort) and fluoxetine (Prozac). Animals were divided into five groups: the normal (N) group without chronic mild stress (CMS), the control (C) group under CMS for 8 weeks, the Nelumbinis Semen (N. s.) treatment group under CMS for 8 weeks, the Hyperium Perforatum (H. p.) treatment group under CMS for 8 weeks and finally, the fluoxetine (F) treatment group under CMS for 8 weeks. Each treatment was administered to rats during the last 4 weeks of the 8-week CMS. A sucrose intake test was performed to test the anti-depression effect of N. s. The N. s. treatment significantly reversed the decreased sucrose intake under CMS (P<0.05 compared to control group under CMS). In the CA2 and CA3 regions of the hippocampus, both N. s. and H. p. reversed the CMS-induced decrease in $5-HT_{1A}$receptor binding. In the I to II regions of the frontal cortex, N. s. and H. p. also reversed the CMS-induced decrease in$5-HT_{1A}$receptor binding, and even showed a significant increase in $5-HT_{1A}$receptor binding compared to the F treatment group (N. s. vs. P, p<0.05, H. p. vs. P, p<0.05). However, in the hypothalamus, all treatments reversed the CMSinduced decrease in $5-HT_{1A}$receptor binding. This reversal effect of N. s. on the decrease in $5-HT_{1A}$receptor binding in the frontal cortex, hippocampus and hypothalamus of rat brains was very similar to that of H. p, but different from that of F. It is concluded that N. s. presents an anti-depression effect through enhancing $5-HT_{1A}$receptor binding.

• Journal of Nutrition and Health
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• v.42 no.6
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• pp.536-546
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• 2009

This study was done to investigate the effect of stress on appetite and eating habits, and other health-related behaviors. The subjects of this study consisted of 188 males and 224 females in Ulsan area. The results were as follows: When stressed, 56% (n = 231) of the subjects experienced a change in appetite and of these, 32% (n = 132) experienced an increased appetite. Stress-induced eating may be one factor contributing to the development of obesity. There was a gender-specific response to stress in which women are more likely to use food to deal with stress, whereas men are more likely to use alcohol consumption or smoking. It was found that types of stressors were individual (52.9%), social (50.7%), family relations (34.5%), work demands (34.2%) and physical environment (32.3%). Stress-induced symptoms of the subjects were anxiety (38.3%), headache (36.7%) and neck or shoulder aches (36.2%), and females experienced those symptoms more than males. Those older than 50 years had a higher eating habit score and lower stress score compared with younger subjects. There were significant differences between sex, age, occupation, family type, BMI, exercise, sleeping hours and eating habits or stress level. This study may be helpful in advancing findings in this area to better provide health professionals with appropriate counseling tools to improve the health of all individuals.

• Korean Journal of Biological Psychiatry
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• v.26 no.2
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• pp.65-70
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• 2019

Objectives The objective of this study is to investigate differences in clinical characteristics between female panic disorder (PD) patients with abortion history (PD+A) and without abortion history (PD-A). Methods We examined data from 341 female patients diagnosed with PD. We divided the patients with PD into PD+A (82 patients) and PD-A (259 patients) to compare demographic and clinical characteristics. The following instruments were applied : stress coping strategies, NEO-neuroticism, the Anxiety Sensitivity Index-Revised (ASI-R), the Albany Panic and Phobia Questionnaire (APPQ), the Beck Depression Inventory, the Beck Anxiety Inventory (BAI) and the Sheehan Disability Scale. Results Compared to the PD-A, the PD+A group showed no significant difference in coping strategies. However, significantly higher scores in neuroticism, the ASI-R, the APPQ and the BAI were observed. In terms of health-related disability, the PD+A group did not show significant difference. Conclusions Our results suggest that the PD+A group may differ from the PD-A group in trait markers such as neuroticism and anxiety sensitivity, and abortion history may be associated with panic-related symptom severity. Our study suggests that further consideration is needed on such clinical characteristics in PD patients with abortion history.