• Title/Summary/Keyword: population control

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Establishment of the Measurement Model about the Adequate Urban Development Density using System Dynamics (시스템다이내믹스를 활용한 도시개발밀도의 적정성 평가 모델 구축 연구)

  • 전유신;문태훈
    • Korean System Dynamics Review
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    • v.4 no.2
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    • pp.71-94
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    • 2003
  • The purpose of this dissertation is to build a development density control model and estimate optimum developmental density level for a sustainable urban growth management. To develop the model, system dynamics modeling approach was used. The model was developed to analyze how urban growth, transition, and decay occur depending on the interaction among population, houses, industry structure, land and urban infrastructure such as road, water supply, and sewage treatment facilities. The model was applied to Anyang city to estimate optimum density level. Extensive computer simulation was conducted to find out the maximum numbers of population, industry structure, houses, and cars that can be adequately sustained with the current Anyang city's infrastructure capacity. The computer simulation result shows that the city is overpopulated by some 90,000 people. It nab analyzed that 20% increase of existing capacity of urban infrastructure is necessary to support current population of Anyang city. To reduce the population to the adequate level whereby the current urban infrastructure can sustain, the current city regulation on floor area ratio needs be strengthened at least 20% to 35%.

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Effects of local conspecific abundance on seed set and seed predation, and control of Carpinus laxiflora (Betulaceae) population density

  • Katori, Takuro;Nakashizuka, Tohru
    • Journal of Ecology and Environment
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    • v.38 no.1
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    • pp.39-45
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    • 2015
  • In this study, the dependence of local conspecific abundance on seed set and predation was examined, and determinates of population density of the temperate tree species Carpinus laxiflora (Betulaceae) in Inagi city, Tokyo, Japan were identified. During a good seed year (2013), seeds were sampled from 27 individuals and categorized as Sound, Empty, Predated, Immature, Decayed, or Broken. Empty seeds were identified as those that failed to fertilize and predation rates were defined as the proportion of seeds that were affected by predators. The proportion of the seed set that was fertilized was significantly positively correlated with local abundance of conspecific trees, while the proportion of seeds that escaped predation was significantly negatively correlated with local abundance of conspecific trees. Thereby, the production of Sound seeds was highest at sites with moderate local conspecific abundance. Although this phenomenon was only observed in a few cases, it clearly showed optimal reproductive success under conditions of moderate density of conspecific reproductive adults, suggesting a mechanism that controls the population density of this species.

Feasibility of Household Surveys for Population Risk Assessment of Cancer and Cancer Registration Support

  • Habib, Omran S;Hussain, Riyadh Abdul-Ameer
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.sup3
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    • pp.213-218
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    • 2016
  • Cancer is a major health problem in the Arab region including Iraq. An adequate database is essential for effective cancer control strategies. Such a database may be provided through cancer registration but supportive household surveys may be useful. This article reports selected results on the feasibility of household surveys to support and validate cancer registration in Basrah governorate - southern Iraq. A large scale multi-stage cluster sample household survey was carried out in Basrah during 2013. It covered 6,999 households and involved gathering data on demographic characteristics and both incident cancer cases and cancer-related deaths among members of these households during a three-year recall period (2010-2012). The data obtained yielded an average annual incidence rate of 91 per 100,000 population (age-standardized incidence rate of 148.8 /100,000) and cancer specific mortality rate of 68 per 100,000 population (age-standardized mortality rate of 126.3/100,000). The results showed an overall pattern of cancer similar to that reported according to cancer registration but the household survey results were consistently higher than those of the cancer registration by a margin of approximately 20- 30% with respect to incident cancer and about 70 % with respect to cancer-specific mortality. Household surveys on cancer, while costly and time consuming, are a very useful additional source of information on cancer at the population level. They can be performed for specific purposes with effective resource mobilization.

Enzyme and Microbial Activities in Paddy Soil Amended Continuously with Different Fertilizer Systems

  • Gadagi, Ravi;Park, Chang-Young;Im, Geon-Jae;Lee, Dong-Chang;Chung, Jong-Bae;Singvilay, Olayvanh;Sa, Tong-Min
    • Korean Journal of Environmental Agriculture
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    • v.20 no.5
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    • pp.325-329
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    • 2001
  • Soil enzyme and microbial activities are affected by fertilizer and compost applications and can be used as sensitive indicators of ecological stability. Microbial population and soil enzymes viz., dehydrogenase, urease, acid phosphatase and aryl-sulphatase were determined in the long-term fertilizer and compost applied paddy soil. Soil samples were collected from the four treatments (control, compost, NPK and compost+NPK). Long-term NPK+compost application significantly increased activities of urease, dehydrogenase and acid phosphatase than all other treatments. The compost application enhanced activities of urease, dehydrogenase and acid phosphatase than the NPK application. However, arylsulfatase activity was not significantly different between compost and fertilizer application. The highest microbial population was recorded in the NPK+compost treatment. The compost application also resulted in higher microbial population than the NPK application. The above results indicate that ecological stability could be maintained by application of compost alone or with NPK.

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Acaricide Resistance in Field-Collected Populations of Tetranychus kanzawai(Acarina: Tetranychidae) (차응애 야외개체군의 살비제 저항성)

  • 김상수;유상선;백채훈
    • Korean journal of applied entomology
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    • v.37 no.2
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    • pp.207-212
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    • 1998
  • Tea field-collected populations of the tea red spider mite (Tetranychus kazawai Kishida) from five different locations in the southern region of Korea were assessed for resistance to seven acaricides using leaf spray method. There were considerable differences in susceptibility depending on the tested acaricides and the location from which the population was collected. The populations showing high resistance ratio of more than 20 with respect to certain acaricide were as follows: the Sungjun and Cheju populations to azocyclotin, tebufenpyrad, fenpyroximate, pyridaben, propargite, and fenpropathrin; the Haenam population to propargite and fenpyroximate; the Bosung population to propargite; the Youngam population to pyridaben. Therefore, the use of other alternative acaricides against the Sungjun and Cheju populations is needed. However, careful selection of the appropriate acaricide against the Haenam, Bosung and Youngam populations of the tea red spider mite might be maintained in effective control.

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A Comparison of Quality of Life between Patients with 12 Months after Coronary Artery Bypass Graft Surgery and General Population (관상동맥 우회술 후 12개월 환자와 일반인의 삶의 질 비교)

  • Song, Yeoung Suk;Lee, Jung Sun
    • Journal of Korean Clinical Nursing Research
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    • v.14 no.1
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    • pp.25-32
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    • 2008
  • Purpose: The purpose of this study was to examine quality of life with patients in 12 months after coronary artery bypass graft surgery, compared with general population. Method: A cross-sectional comparative study was designed. Study participants were 90 adults who had undergone CABG surgery (n=45) in experimental group and general population (n=45) in control group. The subjects were asked the questionnaire (SF-36, Short Form-36) regarding the quality of life. The data were analyzed by the SPSS 13.0 program including frequency, percentage, $x^2$ test, t-test and One-Way ANOVA. Results: There were no significant differences in the quality of life between two groups including physical functioning (t=-.938, p=.351), role-physical limitation (t=-.322, p=.748), bodily pain (t=-.938, p=.351), general health (t=-.1418, p=.888), vitality (t=-.816, p=.417), social functioning (t=.720, p=.474), role-emotional limitation (t=-.710, p=.479), mental health (t=-.431, p=.667). Conclusion: Even though patients in experimental group had operation experience, the quality of life examined on the time of 1 year after bypass surgery is similar in that of general population. We suggest the study change the design as examination of quality of life before and after coronary artery bypass graft surgery.

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Population Dynamics Pattern of Green Peach Aphid (Homoptera: Aphididae) and Its Predator Complex in a Potato System

  • Ro, Tae-Ho;Garrell E. Long
    • Animal cells and systems
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    • v.2 no.2
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    • pp.217-222
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    • 1998
  • Green peach aphid, Myzus persicae(Sulzer) (Homoptera: Aphididae), interacts with many predatory insects in potato fields during the summer. The concept of the predator complex associated with green peach aphids was applied to explain the interactions between the aphid and its predators. The predator power of the predator complex was determined by two factors: the number of predators and the relative feeding capacity. The dynamics of the green peach aphid population was expressed by the number of individuals while the predator power was used to characterize the predator complex. Cumulative degree-days for green peach aphids were used as a time scale to analyze phonology and dynamics patterns of the aphid and its predator complex. The patterns of population changes in aphids were similar during the period of study(1993-1995) although the highest density of aphids fluctuated significantly from year to year. However, the predator power appeared more stable than the green peach aphid population over the three year period. The results indicated that the predator complex plays an important role to suppress the aphid populations during the latter part of the season and that the applications of control measures for green peach aphids in between the initiation and the peak timing of aphid populations are critical to minimize the damage on potatoes.

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Association between Histone Deacetylase 9 Gene Polymorphism and Stroke in Chinese Han Population

  • Yang, Xitong;Xu, Hongyang;Liu, Dan;Ma, Rong;Zhang, Yuanyuan;Wang, Guangming
    • Journal of Korean Neurosurgical Society
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    • v.64 no.2
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    • pp.309-315
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    • 2021
  • Objective : To explore the correlation between the polymorphism of histone deacetylase 9 gene (rs1060499865, rs723296, rs957960) and ischemic stroke (IS) in Chinese Han population in Dali region. Methods : This study included 155 IS patients and 128 healthy physical examinees. TaqMan-polymerase chain reaction technology and multivariate logistic regression were performed. Results : In the case group, there was no polymorphism of rs1060499865 observed in the two groups; whereas on the rs723296 locus the frequencies of C allele and TC genotype were significantly higher than that in the control group, alleles C and T were associated with a 2.158-fold increase in IS risk, and genotypes TC and TT were associated with a 2.269-fold increase in IS risk. The locus rs957960 exhibited no significant difference between the two groups. Conclusion : An association between rs723296 and the risk of IS was found in the Chinese Han population in Dali region. No significant association was found between rs1060499865, rs957960 and IS in the Chinese Han population in Dali region.

First detection of ranavirus in a wild population of Dybowski's brown frog (Rana dybowskii) in South Korea

  • Park, Jaejin;Grajal-Puche, Alejandro;Roh, Nam-Ho;Park, Il-Kook;Ra, Nam-Yong;Park, Daesik
    • Journal of Ecology and Environment
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    • v.45 no.1
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    • pp.10-16
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    • 2021
  • Background: Ranavirus is an emerging infectious disease which has been linked to mass mortality events in various amphibian species. In this study, we document the first mass mortality event of an adult population of Dybowski's brown frogs (Rana dybowskii), in 2017, within a mountain valley in South Korea. Results: We confirmed the presence of ranavirus from all collected frogs (n = 22) via PCR and obtained the 500 bp major capsid protein (MCP) sequence from 13 individuals. The identified MCP sequence highly resembled Frog virus 3 (FV3) and was the same haplotype of a previously identified viral sequence collected from Huanren brown frog (R. huanrenensis) tadpoles in South Korea. Human habitat alteration, by recent erosion control works, may be partially responsible for this mass mortality event. Conclusion: We document the first mass mortality event in a wild Korean population of R. dybowskii. We also suggest, to determine if ranavirus infection is a threat to amphibians, government officials and researchers should develop continuous, country-wide, ranavirus monitoring programs of Korean amphibian populations.

Difference of Sagittal Spinopelvic Alignments between Degenerative Spondylolisthesis and Isthmic Spondylolisthesis

  • Lim, Jae Kwan;Kim, Sung Min
    • Journal of Korean Neurosurgical Society
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    • v.53 no.2
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    • pp.96-101
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    • 2013
  • Objective : The purpose of this study was to analyze the differences of spinopelvic parameters between degenerative spondylolisthesis (DSPL) and isthmic spondylolisthesis (ISPL) patients. Methods : Thirty-four patients with DSPL and 19 patients with ISPL were included in this study. Spinopelvic parameters were evaluated on whole spine X-rays in a standing position. The following spinopelvic parameters were measured : pelvic incidence (PI), sacral slope, pelvic tilt (PT), lumbar lordosis (LL), and sagittal vertical axis from C7 plumb line (SVA). The population of patients was compared with a control population of 30 normal and asymptomatic adults. Results : There were statistically significant differences in LL (p=0.004) and SVA (p=0.005) between the DSPL and ISPL group. The LL of DSPL ($42{\pm}13^{\circ}$) was significantly lower than that of the control group ($48{\pm}11^{\circ}$; p=0.029), but that of ISPL ($55{\pm}6^{\circ}$) was significantly greater than a control group (p=0.004). The SVA of DSPL ($55{\pm}49$ mm) was greater than that of a control group (<40 mm), but that of ISPL ($21{\pm}22$ mm) was within 40 mm as that of a control group. The PT of DSPL ($24{\pm}7^{\circ}$) and ISPL ($21{\pm}7^{\circ}$) was significantly greater than that of a control group ($11{\pm}6^{\circ}$; p=0.000). Conclusion : Both symptomatic DSPL and ISPL patients had a greater PI than that of the asymptomatic control group. In conclusion, DSPL populations are likely to have global sagittal imbalance (high SVA) compared with ISPL populations because of the difference of lumbar lordosis between two groups.