• 제목/요약/키워드: distribution of exposure factors

검색결과 105건 처리시간 0.022초

Spatial Heterogeneity and Long-term Changes in Bivalve Anadara broughtoni Population: Influence of River Run-off and Fishery

  • Silina, Alla V.
    • Ocean Science Journal
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    • 제41권4호
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    • pp.211-219
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    • 2006
  • A comparison was made of population of the economically important cockle Anadara (=Scapharca) broughtoni (Bivalvia, Arcidae) inhabiting different areas of the Razdolnaya River estuary at the head of Amurskii Bay (Peter the Great Gulf, East Sea). Also, changes in cockle population density and structure, as well as in cockle growth rates during the last 20 years were studied. In all years of investigation, the morphometrical parameters and growth rates of cockles were smaller at the sites located close to the River mouth than farther down-estuary. The differences can be attributed to higher concentration of suspended particulate matter, decreased salinity and water temperature, as well as a longer exposure to these unfavorable environmental factors at sites located close to the River mouth, compared to farther sites. For two decades, cockle population density had decreased by almost 30 times at some sites in the River estuary. The main reason for this population decline is commercial over-fishing of the cockle. Besides, for the last 20 years, linear parameters of the cockles in the population decreased approximately by 30% and weight parameters, almost two times. Cockle growth rates also decreased for this period. Evidently, these facts are due to the damaging effect of dredging.

금융사무원의 심리사회적 작업환경과 정신건강 (Psychosocial Working Environment and Mental Health of Financial Clerks)

  • 이복임;이주현
    • 한국직업건강간호학회지
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    • 제30권4호
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    • pp.224-231
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    • 2021
  • Purpose: The purpose of this study was to identify the psychosocial working environment and mental health of financial workers, and analyze the impact of the former on the latter. Methods: Data of 257 financial clerks were extracted from the 2017 5th Korean Working Conditions Survey. Psychosocial working environment was divided into five fields: demands at work, work organizations, interpersonal relations, workplace violence, and working hour quality. Mental health included sleeping problems, psychological well-being, and job stress. Results: A total of 6.1% subjects reported sleep problems, 28.2% experienced poor psychological well-being, and 39.6% had job stress. More than half the subjects were exposed to tight deadlines, complex tasks, hiding feelings at work, fair treatment, fair distribution of work, colleagues' support, and managers' support. Tight deadlines, workplace violence, long working hours, hiding feelings at work, and managers' support had a significant impact on the mental health of financial clerks. Conclusion: Based on the results of this study, we propose that employers, workers, and health managers in the financial industry should work together to establish a respectful organizational culture, prevent long working hours through recruitment, and conduct programs to protect emotional health.

Growing Environment Characteristics and Vegetation Structure of Daphne Pseudomezereum var. Koreana Native Habitats in Korea

  • Lee, Da-Hyun;Son, Ho-Jun;Park, Sung-Hyuk;Kim, Se-Chang;Park, Wan-Geun
    • Journal of Forest and Environmental Science
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    • 제35권1호
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    • pp.31-40
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    • 2019
  • Daphne pseudomezereum var. koreana is an endangered deciduous shrub distributed in mountain areas that is vulnerable to climate change. The purpose of this study was to provide foundational data on the physical characteristics, soil environment, and vegetation structure of habitats of Daphne pseudomezereum var. koreana habitat in Korea in order to help with management decisions on ecosystem restoration. Rock exposure was 15 to 35%, with an average of 24%. The native habitat of D. pseudomezereum included 129 taxa consisting of 46 families and 95 genera. Two-way cluster analysis divided the habitat into three plant communities: Community I (dominaterd by Tilia amurensis and Quercus mongolica), Community II (dominaterd by Fraxinus rhynchophylla and Acer pseudosieboldianum), and Community III (dominaterd by Ulmus davidiana var. japonica). The diversity indices for Communities I, II, and III were 1.124, 1.047 and 0.932, respectively. The soils were loam or clay loam. Soil pH, organic matter content, and available phosphoric acid were 5.40, 14.38%, and 31.08 ppm, respectively. Ordination analysis resulted that most significant factors influencing D. pseudomezereum distribution were magnesium content of soil, shrub layer, and altitude.

Inhibitory Effects of Ramulus Mori Extracts on Melanogenesis

  • Lee, Ghang-Tai;Shin, Bong-Soo;Kim, Beom-Jun;Kim, Jeong-Ha;Jo, Byoung-Kee
    • 대한화장품학회지
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    • 제23권2호
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    • pp.63-70
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    • 1997
  • It has been observed that local increase in melanin synthesis or uneven distribution can cause local hyperpigmintation or spot. Pigmentary disorders are caused by various factors, including inflammation, imbalance of hormones, and genetic disorder. Recently the harmfulness of Ultraviolet radiation is increasing due to destruction of ozone layer. Excessive exposure to UV radiation caused post-inflammatory pigmentation. Most women want to avoid uneven skin pigmentation. To satisfy this desire many cosmetic companies have been developing melanogenesis inhibitors and finding promising active agents for use in cosmetic preparations for skin whitening. In cosmetic preparations, many inhibitors such as kojic acid, arbutin, ascorbic acid, and licorice extracts6 have been used as whitening purpose. Plant extracts having an inhibitory effect on melanin formation may be a good choice for cosmetic purpose because of their relatively lower side effects. Therefore, we screened 285 plant extracts for their inhibitory activity in tyrosinase. Of the plant extracts, ramulus mori extracts showed potent tyrosinase inhibition activity. We also identified the active compound in the extract.

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Space-time-dissociated differential sedimentation and its relationship with the rate of relative sea-level change: the Lower Ordovician Mungok Formation, Korea

  • Choi Yong Seok;Lee Yong Il
    • 한국석유지질학회:학술대회논문집
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    • 한국석유지질학회 2000년도 제7차 학술발표회 발표논문집
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    • pp.14-30
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    • 2000
  • Hierarchically controlled sequence stratigraphic analysis shows that the Lower Ordovician mixed carbonate-siliciclastic Mungok Formation, Korea consists of three depositional sequences: T1, T2, and T3. Sequence boundaries are generally marked by abrupt transition from coarse-grained shallow-water carbonates to fine-grained deeper-water carbonates mixed with fine-grained siliciclastics, and show indication of subaerial exposure such as karstification. Within this sequence stratigraphic framework, facies characteristics indicate that the Mungok sequences were mostly deposited in subtidal ramp environments. High-frequency cycles consist of upward-shallowing facies successions. Cycles of shallow-water and basinal deposits are not represented well, probably due to cycle amalgamation. Cycle stacking patterns do not show a consistent thickness change that reflects a large-scale sea-level change due to unfilled accommodation space. The Mungok sequences show that many factors including relative sea-level change and topography are involved in controlling sequence development on carbonate ramps. The depositional setting evolved from the high-energy ramps in the sequences T1 and T2 into the low-energy ramp in the sequence T3. Topography is interpreted to have been responsible for the different energy regimes of the carbonate ramps in the Mungok sequences. The high ramp gradient in the sequences T1 and T2 seems to be caused by space-time-dissociated differential sedimentation resulting in spatially narrow distribution of sediment filling, which in turn may be related to high rate of relative sea-level change. In contrast, low ramp gradient was maintained in the sequence T3 during slow changes of relative sea level resulting in broad distribution of sediment filling.

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이전 가격 트렌드가 낙관적 예측에 미치는 영향 (The Effect of Prior Price Trends on Optimistic Forecasting)

  • 김영두
    • 산경연구논집
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    • 제9권10호
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    • pp.83-89
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    • 2018
  • Purpose - The purpose of this study examines when the optimism impact on financial asset price forecasting and the boundary condition of optimism in the financial asset price forecasting. People generally tend to optimistically forecast their future. Optimism is a nature of human beings and optimistic forecasting observed in daily life. But is it always observed in financial asset price forecasting? In this study, two factors were focused on considering whether the optimism that people have applied to predicting future performance of financial investment products (e.g., mutual fund). First, this study examined whether the degree of optimism varied depending on the direction of the prior price trend. Second, this study examined whether the degree of optimism varied according to the forecast period by dividing the future forecasted by people into three time horizon based on forecast period. Research design, data, and methodology - 2 (prior price trend: rising-up trend vs falling-down trend) × 3 (forecast time horizon: short term vs medium term vs long term) experimental design was used. Prior price trend was used between subject and forecast time horizon was used within subject design. 169 undergraduate students participated in the experiment. χ2 analysis was used. In this study, prior price trend divided into two types: rising-up trend versus falling-down trend. Forecast time horizon divided into three types: short term (after one month), medium term (after one year), and long term (after five years). Results - Optimistic price forecasting and boundary condition was found. Participants who were exposed to falling-down trend did not make optimistic predictions in the short term, but over time they tended to be more optimistic about the future in the medium term and long term. However, participants who were exposed to rising-up trend were over-optimistic in the short term, but over time, less optimistic in the medium and long term. Optimistic price forecasting was found when participants forecasted in the long term. Exposure to prior price trends (rising-up trend vs falling-down trend) was a boundary condition of optimistic price forecasting. Conclusions - The results indicated that individuals were more likely to be impacted by prior price tends in the short term time horizon, while being optimistic in the long term time horizon.

한국 성인 비만 집단의 탄수화물 급원 식품 섭취 분포 및 노출 위험도: 대규모 한국인유전체 역학 자료 활용 (Distribution and Exposure Prevalence of Carbohydrate-based Food Intake among Obese Korean Adults Based on the Health Examinees (HEXA) Study)

  • 한유리;권성옥;이상아
    • 대한지역사회영양학회지
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    • 제22권2호
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    • pp.159-170
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    • 2017
  • Objectives: The purpose of this study was to estimate the distribution and exposure prevalence of total carbohydrate intake and the carbohydrate-based foods such as rice, noodles, sweet potatoes, sweet drinks, milk and fruits and to characterize intake patterns among obese Korean adults. Methods: Subjects included 137,363 adults aged 40 years or older who participated in a Health Examinees (HEXA) Study. Multiple regression analysis of data from Semi-Quantitative Food Frequency Questionnaire (SQFFQ) identified food sources of carbohydrates. Weight, height and waist circumstance (WC) were measured, and the body mass index (BMI) was calculated. Obesity was defined as $BMI{\geq}25kg/m^2$ and abdominal obesity as $WC{\geq}90cm$ and ${\geq}85cm$ for males and females, respectively. Results: Obese adults appeared to have a higher total carbohydrate intake in the univariate analysis but had eaten less after adjustment for general and lifestyle factors, compared to normal weight adults (OR 0.78, 95% CI 0.73-0.82 for general obesity; OR 0.79, 95% CI 0.74-0.85, for abdominal obesity; P trend < 0.0001, respectively). Based on advance analysis for the food sources of carbohydrates, obese subjects had lower intake of rice (OR 0.86, 95% CI 0.68 -1.09 for general obesity; OR 0.87, 95% CI 0.67-1.13, for abdominal obesity; P trend < 0.0001, respectively) and higher intake of noodles (OR 1.21, 95% CI 1.16-1.27 for general obesity; OR 1.25, 95% CI 1.19-1.32, for abdominal obesity; P trend < 0.0001 respectively). With regard to other food sources of carbohydrates such as milk and fruits, intake was lower among obese compared to normal weight subjects. Conclusions: In the Korean middle-aged and older obesity groups, the intake of carbohydrates and the related foods was lower than in normal weight subjects, except for noodles. We conclude that a higher intake of noodles may enhance weight-gain. Therefore, this study suggested that the guidelines should consider the types of carbohydrate sources and the amount consumed from foods in order to provide proper guidance with regard to control and prevent obesity among Korean adults.

칠게 외골격 표면 거칠기를 이용한 노출 독성 평가: 새로운 융합적 연구 (Toxicological Assessment to Environmental Stressors Using Exoskeleton Surface Roughness in Macrophthalmus japonicus: New Approach for an Integrated End-point Development)

  • 박기연;곽인실
    • 생태와환경
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    • 제54권4호
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    • pp.265-271
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    • 2021
  • 갑각류 외골격은 키틴질로 이루어져 있고 외부자극에 보호와 지지를 위해 주요한 기능을 한다. 수환경은 물리적 변화뿐만 아니라 다양한 해양 오염에 끊임없이 영향을 받고 그 환경에 서식하는 생물은 생존을 위해 생물학적으로 반응한다. 본 연구에서는 이르가롤 독성노출이나 퇴적환경 중금속 분포에 따라 서식하는 칠게의 외골격 표면조도 분석을 통한 생태독성 종말점이 될 수 있음을 제시하였다. 칠게의 외골격 표면 조도는 이르가롤 노출에 대해 거칠기(Ra)도 감소하고 조도 변이(variation)도 줄어들었다. 또한 해양 연안 퇴적물 내 중금속(Cd, Pb, Hg) 분포에 따라 서식하는 칠게에서 표면 거칠기 및 변이가 변화하는 것을 확인하였다. 이러한 외골격 표면 거칠기의 변화는 외부환경 스트레스 요인에 따른 칠게의 생물학적인 반응 종말점(end-point)을 나타내며 나아가 외골격의 보호, 지지, 수송 등의 기능적 면에 영향을 미칠 수 있음을 시사한다. 이러한 접근방법은 공학과 생물의 융합적 기술로 수환경 모니터링을 위한 유용한 방법으로 활용될 수 있을 것이다.

수영장 활동공간 내 유해인자 노출특성 연구 (Characteristics of Exposure Distribution to Hazard Factors in Indoor Swimming Pool Activity Areas in Gwangju)

  • 이윤국;김난희;최영섭;김선정;박주현;강유미;배석진;서계원;김종민
    • 한국환경보건학회지
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    • 제46권2호
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    • pp.150-158
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    • 2020
  • Objective: This study is designed to measure the concentration of DBPs (disinfection by-products) in pool water and in air and to estimate the carcinogenic potential through the evaluation of inhalation exposure. Methods: The subjects were six indoor swimming pools with many users in Gwangju. Samples of pool water and indoor air were taken every one month from August 2018 to August 2019 and analyzed for eight swimming pool standards. Three-liter air samples were collected and the VOCs were analyzed using GC/MS directly connected to thermal desorption. Results: pH was 6.8-7.5 and the concentration of free residual chlorine in pool water was 0.40-0.96 ?/ℓ. Physicochemical test items such as KMnO4 consumption and heavy metal items such as Aluminum met existing pool hygiene standards. No VOC materials were detected except for the DBPs. The concentration of THMs in the pool water was 11.05-41.77 ㎍/L and the THMs mainly consist of Chloroform (63-97%) and BDCM (3-31%). The concentration of indoor air THMs is 13.24-32.48 ㎍/㎥ and consists of Chloroform. The results of carcinogenic assessment of chloroform in the indoor swimming pool via inhalation exposure were 2.0 to 6.4 times higher than the 'acceptable risk level' suggested by the US EPA. Conclusions: The concentration of THMs in the pool water is 11.05-41.77 ㎍/L, most of which is chloroform. In addition, the concentration of indoor air THMs is 13.24-32.48 ㎍/㎥. The result of carcinogenic assessment of chloroform was 2.0 to 6.4 times higher than the 'acceptable risk level' suggested by the US EPA.

Spatial Analysis of Breast Cancer Incidence in Iran

  • Mahdavifar, Neda;Pakzad, Reza;Ghoncheh, Mahshid;Pakzad, Iraj;Moudi, Asieh;Salehiniya, Hamid
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권sup3호
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    • pp.59-64
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    • 2016
  • Breast cancer (BC) is the most common cancer in females (27% of the total) and the main cause of death (16%) due to cancer in women in developed and developing countries. Variations in its incidence rate among geographical areas are due to various contributing factors. Since there have been a lack of studies on this topic in our country, the present spatial analysis of breast cancer incidence in Iran in 2009 was conducted using data from the national cancer registry system. The reported incidences of the disease were standardized according to the World Health Organization population and the direct method. Then data was inserted into the GIS software and finally, using the Hot Spot Analysis (Geties-Ord Gi), high-risk areas were drawn. Provinces with incidences 1.96 SD higher or lower than the national average were considered as hot spots or cold spots, at the significance level of 0.05%. In 2009, a total of 7,582 cases of BC occurred in Iran. The annual incidence was 33.2 per hundred thousand people. Our study showed that the highest incidence of BC in women occurred in the central provinces of the country, Tehran, Isfahan, Yazd, Markazi and Fars. The results of hot spots analysis showed that the distribution of high-risk BC was focused in central parts of Iran, especially Isfahan province (p <0.01). The other provinces were not significantly different from the national average. The higher incidence in central provinces may be due to greater exposure to carcinogens in urban areas, a Western lifestyle and high prevalence of other risk factors. Further epidemiological studies about the etiology and early detection of BC are essential.