• Title/Summary/Keyword: population characteristics

Search Result 3,419, Processing Time 0.038 seconds

Estimation of mortality coefficients and survivorship curves for minke whales (Balaenoptera acutorostrata) in Korean waters

  • Zhang, Chang-Ik;Song, Kyung-Jun;Na, Jong-Hun
    • Animal cells and systems
    • /
    • v.14 no.4
    • /
    • pp.291-296
    • /
    • 2010
  • Population ecological characteristics of growth and mortality play an important role in understanding the population dynamics of marine mammals. The instantaneous coefficients of natural and bycatch mortality were estimated for minke whales (Balaenoptera acutorostrata) in Korean waters using a population assessment model composed of bycatch and abundance data. The survivorship curve of this population was fitted to the data, and then the curve was revised using age-specific relative bycatchability coefficients ($q_t$). Instantaneous coefficients of natural and bycatch mortality of minke whales were estimated as 0.024/year and 0.076/year, respectively, and from this the survival rate was estimated as 0.905. This estimated survival rate was comparable to other cetaceans in other regions. The $q_t$ for this population ranged from 0.020 to 0.193. The revised survival rates were higher when the $q_t$ was taken into account. The mortality coefficient, survival rate, $q_t$ and survivorship curves had not previously been determined for minke whale in this area. This estimate could serve as fundamental information to assess the status of this population and for conservation and rational management.

Impact of Area Characteristics on the Health of Vulnerable Populations in Seoul (지역특성이 취약집단 건강에 미치는 영향 분석)

  • Kim, Youn-Hee;Cho, Young-Tae
    • Korea journal of population studies
    • /
    • v.31 no.1
    • /
    • pp.1-26
    • /
    • 2008
  • This research examines the effect of area level characteristics on individual health, particularly focusing on the vulnerable populations in Seoul. We consider adult individuals whose family income is under 1.5 million won, who are aged 65 and over, or who have neither spouse nor job but aged 40 and over as vulnerable populations. Using the 2005 Seoul Citizens' Health Interview Survey, we conducted multilevel analyses to simultaneously investigate the effect of area and individual level characteristics on health. Between-area variance of self-rated health status was greater for the elderly population than for all populations. Area material deprivation index and happiness index were associated with the self-rated health of economically disadvantaged populations. Vulnerable populations showed greater between-area variances in emotional health than the same for all populations. Area happiness index, material deprivation index, the proportion of households below poverty line and street safety showed statistically significant association with emotional health. The effect of area characteristics were particularly salient for the emotional health of elderly population and its between area variance was also notable.

Characteristics of Intra and Inter-Regional Population Mobility Resulting from Innovative City Development (혁신도시 건설에 따른 권역내·외 인구이동 특성)

  • Seong-Won KANG;Tae-Heon MOON;Hye-Lim KIM
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.26 no.4
    • /
    • pp.1-16
    • /
    • 2023
  • In 2005, the selection of 10 innovation cities was completed, and since 2013, public institutions began relocating to innovation cities. As a policy aimed at promoting balanced regional development, there were significant expectations from the regions. However, although the population moving to innovation cities has increased, it remains to be seen how much inflow is from the capital region and what spatial characteristics exist nationwide. Therefore, this study aims to analyze whether the innovation cities are fulfilling their roles by examining the patterns of inflow from the capital region and the spatial characteristics, and to reassess the policy direction for future innovation cities. We utilized the Microdata Integrated Service (MDIS) provided by Statistics Korea from 2013 to 2021. For the data collection reasons, we focused on analyzing the three cities. The results showed that in the initial stages of innovation city development, there was a significant influx of population from the capital region, leading to some effects on population dispersion and balanced regional development. However, over time, a phenomenon emerged where more people started to move back to the capital region, indicating a problematic trend. Furthermore, the Gyeongbuk Innovation City and Gwangju-Jeonnam Innovation City showed similarities in terms of reasons for migration, age of householder, and number of household members. However, the Gyeongnam Innovation City exhibited distinct characteristics compared to the other two cities. While the reasons for this phenomenon may be diverse, the current situation suggests that the goal of achieving "balanced national development" has reached its limits. Therefore, urgent measures need to be taken for improvement that take regional characteristics into account. Furthermore, in designing the second phase of the public institution relocation plan is required to avoid repeating the same issues and ensure a more thoughtful approach.

Growth and Maturation Period of Silvetia siliquosa in the Natural Population in Jindo, South Korea (한국 진도의 자연군락 뜸부기(Silvetia siliquosa)의 생장과 성숙 주기)

  • Hwang, Eun Kyoung;Yoo, Ho Chang;Ha, Dong Soo;Park, Chan Sun
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.48 no.5
    • /
    • pp.745-751
    • /
    • 2015
  • The ecological characteristics of Silvetia siliquosa, an endangered brown alga, were investigated from January to December 2013 in Jindo, South Korea. The S. siliquosa population formed widespread patches on natural rock. Receptacles were observed from March to August when seawater temperatures ranged from 8-26℃. A maturation peak was detected in June, when seawater temperatures were 23.4℃. After embryo release, the alga bleached and only the discoidal holdfast remained after August. Developmental initiation of the thallus occurred at temperatures above 8℃, and receptacle formation required approximately 196 degree-days. This is the first study to examine a S. siliquosa population throughout the entire year in a natural habitat.

No Association of the Human Y Chromosome with Blood Pressure in Korean Male Population

  • Kang, Byung-Yong;Kim, Seon-Jeong;Lee, Kang-Oh
    • Toxicological Research
    • /
    • v.19 no.1
    • /
    • pp.29-31
    • /
    • 2003
  • It has been reported that the genetic variations in the Y chromosome has influence the blood pressure in some Caucasian male populations, but the effect in non-Caucasian population is unclear. In the present study, we examined the relationship between blood pressure and a HindIII RFLP of Y chromosome in 152 unrelated male individuals of ethnically homogeneous Korean origin. There were no significant differences in systolic and diastolic blood pressures between genotype groups, respectively. However, the frequency of A genotype in Korean population was much higher than those of Caucasian populations (P<0.05). Therefore, the results of this study will con-tribute the better understanding the genetic characteristics of Y chromosome in Korean population.

Analysis of Factors Affecting Peak Loading Coefficient of Sewer Works in Korea (우리나라 하수도시설의 첨두부하율 영향요소 분석)

  • Hyun, In-Hwan;Lee, Young-Ho
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.25 no.6
    • /
    • pp.877-884
    • /
    • 2011
  • Although peak loading coefficient is one of critical design factors for sewer works, its detailed affecting factors were not analyzed because of limited data availability. This study analyzed the affecting factors on peak loading coefficient with plenty data obtained from several newly constructed sewer works. Simple and multiple regression analysis methods were adopted to analyze the relationships of each variable with or without data filtering. Drainage population, drainage area, population density, and daily sewage flow per person showed very weak relationships under diverse characteristics of cities. However, daily sewage flow per person showed stronger relationships with peak loading when daily sewage flow per person was splitted into two ranges. Population density (i.e., drainage population divided by drainage area) and daily sewage flow per person considerably were related with peak loading coefficient when daily sewage flow per person is less than about 400 Lpcd.

Femtosecond Photoelectron Imaging of N2 at 410 nm

  • Guo, Wei;Wei, Shanshan;Lu, Xingqiang;Wang, Li
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.12
    • /
    • pp.3693-3696
    • /
    • 2010
  • We experimentally measure the kinetic energy and angular distributions of photoelectrons of $N_2$ as a function of 410 nm femtosecond laser intensity by using velocity map imaging technique. The strong-field multiphoton ionization of molecules shares many of the characteristics with those of atoms. Electron kinetic energies are nearly independent of laser intensities. The independence suggests that the electron peaks in the photoelectron spectrum actually result from a two-step process, indicative of the occurrence of real population in the intermediate states. The relative amplitudes of electron peaks indicate that in the two-step process, nonresonant population transfer dominates for low intensities, while resonant population transfer dominates for higher intensities.

Regional Disparities of Suicide Mortality by Gender (성별에 따른 지역 간 자살률 차이 및 영향요인 분석)

  • Seo, Eun-Won;Kwak, Jin-Mi;Kim, Da-Yang;Lee, Kwang-Soo
    • Health Policy and Management
    • /
    • v.25 no.4
    • /
    • pp.285-294
    • /
    • 2015
  • Background: Suicide is one of important health problems in Korea. Previous studies showed factors associated with suicide in individual levels. However, suicide was influenced by society that individuals belong to, so it was required to analyze suicide in local levels. The purpose of this study was to analyze the regional disparities of suicide mortality by gender and the association between local characteristics and suicide mortality. Methods: This study included 229 city county district administrative districts in Korea. Age- and sex-standardized suicide mortality and age-standardized suicide mortality (male/female) were used as dependent variables. City county district types, socio-demographics (number of divorces per 1,000 population, number of marriages per 1,000 population, and single households), financial variable (financial independence), welfare variable (welfare budget), and health behavior/status (perceived health status scores and EuroQol-5 dimension [EQ-5D]) were used to represent the local characteristics. We used hot-spot analysis to identify the spatial patterns of suicide mortality and negative binomial regression analysis to examine factors affecting suicide mortality. Results: There were differences in distribution of suicide mortality and hot-spot regions of suicide mortality by gender. Negative binomial regression analysis provided that city county district types (city), number of divorces per 1,000 population, financial independence, and EQ-5D had significant influences on the age- and sex-standardized suicide mortality per 100,000. Factor influencing suicide mortality was the number of divorces per 1,000 population in both male and female. Conclusion: Study results provided evidences that suicide mortality among regions was differed by gender. Health policy makers will need to consider gender and local characteristics when making policies for suicides.

Differences of Chemical Exposure Levels according to Residential and Personal Life-style Characteristics of Korean adult population - from Korean National Environmental Health Survey (주거환경 및 개인 생활습관에 따른 화학물질 노출수준 차이 - 국민환경보건기초조사)

  • Hwang, Moon-Young;Hong, Soo-Yoen;Kwon, Young-Min;Jo, Hye-Jung;Park, Choong-Hee
    • Journal of Environmental Health Sciences
    • /
    • v.45 no.2
    • /
    • pp.142-153
    • /
    • 2019
  • Objectives: The aim of this study was to determine environmental chemical exposure related to residential and personal lifestyle characteristics in the adult Korean population. The observations of this study can provide information useful for developing reduction approaches for exposure to chemicals among the general adult population. Methods: The second stage of the Korean National Environmental Health Survey (KoNHES) was conducted from 2012 to 2014, with 6,478 persons participating. Using the results of the survey, the relationship between exposure levels of heavy metals and organic chemicals and exposure factors, e.g. residential and personal lifestyle characteristics, were analyzed. Results: The exposure levels of VOCs and PAHs were significantly lower in participants living at a distance of more than 100 m from roads versus living closer to roads. Home ventilation lowered VOC and PAH exposure but did not lower chemical exposure from household products. Use of public transportation showed lower exposure to heavy metals, VOCs, and PAHs. Current smoker was significantly higher for levels of heavy metals, VOCs, and PAHs, and the exposure trend was similar for current drinkers. Physical activity was related with higher exposure to phthalates and environmental phenols. Conclusion: Our observations based on a nationally representative population for Korea show that exposure to chemicals varies by residential and personal lifestyle, and this should be considered for developing appropriate mitigation measures and policies. Given the health concerns surrounding environmental chemicals, it is necessary to develop comprehensive measures to reduce chemical exposure.

Analysis of genetic characteristics of pig breeds using information on single nucleotide polymorphisms

  • Lee, Sang-Min;Oh, Jae-Don;Park, Kyung-Do;Do, Kyoung-Tag
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.32 no.4
    • /
    • pp.485-493
    • /
    • 2019
  • Objective: This study was undertaken to investigate the genetic characteristics of Berkshire (BS), Landrace (LR), and Yorkshire (YS) pig breeds raised in the Great Grandparents pig farms using the single nucleotide polymorphisms (SNP) information. Methods: A total of 25,921 common SNP genotype markers in three pig breeds were used to estimate the expected heterozygosity ($H_E$), polymorphism information content, F-statistics ($F_{ST}$), linkage disequilibrium (LD) and effective population size ($N_e$). Results: The chromosome-wise distribution of $F_{ST}$ in BS, LR, and YS populations were within the range of 0-0.36, and the average $F_{ST}$ value was estimated to be $0.07{\pm}0.06$. This result indicated some level of genetic segregation. An average LD ($r^2$) for the BS, LR, and YS breeds was estimated to be approximately 0.41. This study also found an average $N_e$ of 19.9 (BS), 31.4 (LR), and 34.1 (YS) over the last 5th generations. The effective population size for the BS, LR, and YS breeds decreased at a consistent rate from 50th to 10th generations ago. With a relatively faster $N_e$ decline rate in the past 10th generations, there exists possible evidence for intensive selection practices in pigs in the recent past. Conclusion: To develop customized chips for the genomic selection of various breeds, it is important to select and utilize SNP based on the genetic characteristics of each breed. Since the improvement efficiency of breed pigs increases sharply by the population size, it is important to increase test units for the improvement and it is desirable to establish the pig improvement network system to expand the unit of breed pig improvement through the genetic connection among breed pig farms.