• Parasites, Hosts and Diseases
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• v.62 no.1
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• pp.64-74
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• 2024

This pilot study aimed to investigate the effects of regional and seasonal variations on the prevalence of Theileria orientalis and the hematological profile of non-grazed dairy cows in Korea. A total of 365 clinically healthy lactating Holstein Friesian cows from 26 dairy farms in 7 provinces that were categorized into northern, central, and southern regions were sampled during the warm period from July to August and the cold period from October to December. The detection of T. orientalis major piroplasm surface protein gene and the hematology non-grazed dairy cows were analyzed using peripheral blood samples. The T. orientalis prevalence was 20.0% (73/365). The prevalence in the southern region was 35.9%, which was significantly higher than that in the central (21.6%) and northern (12.9%) regions (P<0.05). The prevalence during warm period was higher (43.0%) than that during the cold season (13.5%). The infected cows showed significantly lower erythrocyte counts in the southern region (5.8±0.6 M/㎕) and during the warm period (5.8±0.7 M/㎕) compared with those in the central and northern regions and during the cold season, which affected the extended RBC parameters, including hematocrit and hemoglobin concentrations. Our findings revealed the prevalence of T. orientalis in Korea, highlighting its high occurrence during warm periods and in certain geographical regions. Climatic factors could contribute to the health and productivity of cattle, as evidenced by the prevalence of T. orientalis and its negative impact on animals.

• Journal of the Korean association of regional geographers
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• v.6 no.1
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• pp.1-28
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• 2000

The purpose of this study is to clarify the suburbanization of manufacturing, and location and linkages of decentralized manufacturing from Metropolitan Pusan by means of case study on manufacturing location and linkages in the suburb of Metropolitan Pusan. Kimhae city and Yangsan-Gun toward which heavy decentralization of manufacturing from the Metropolitan Pusan has been done. Both hard data and soft data were used as the basic data. Hard data are the statistical data in statistical yearbooks and firm list in directories. The former consists of the number of establishments and employees classified by product type, firm size and unit area. The latter consists of owner's names, addresses, employee number, products and headquarters of firms. Soft data are the results of the interviews with the 242 owners of firms in the four case study areas selected by Proportional Stratified Sampling Method. The major findings are as follows: 1. The spatial variations of manufacturing in the suburb was regularized in the latter half of 1970's. The primary processes to decentralize manufacturing from Metropolitan Pusan were the birth, relocation and establishment of branches of the firms. Among them the relocation of small outer-oriented single-location firms from Pusan was the most important. 2. The spatial variations undergoing spatial expansion of manufacturing distribution and increase of agglomeration degree of manufacturing, proceeded from the adjacents of Metropolitan Pusan to the outer areas along the main transportation route. 3. The main factors which caused manufacturing to decentralize from the Metropolitan Pusan were firm policy and land for this policy. The main locational factors which induced the decentralizing manufacturing into the suburb were land, market and transportation. 4. The strength of linkages with the outside of the study area is stronger than that of linkages with the inside. There is distance-decay-function in the strength of linkages with the outside, and linkages with short distant areas are stronger than those with long distant areas. 5. The ranges of spatial linkages in procurement of materials, in subcontraction and in marketing are wider than those in ordering. 6. The main factors which cause the formation of linkages are different by types of linkages: monopolistic and oligopolistic supply are important in procurement linkages; characteristics of products and the subsequent marketing difficulties, in subcontraction linkages; fluctuation, cost reduction, insufficient facility and characteristics of products, in ordering linkages; subcontract, characteristics of product and the subsequent marketing difficulties, in marketing linkages. 7. The changes of linkages owing to locational changes of firms were great, and were greater in long distant areas than in short distant areas. 8. The main factor influencing on the changes of linkages was the easiness in the transportation of goods, movement of labour and contacts with customers. In conclusion, some facts described above were proved to be consistent with the results of proceeding studies in the other areas: influence of relocation of decentralizing firms on the suburbanization; the factors of manufacturing decentralization; spatial characteristics of linkages; linkage changes owing to relocation of firms. Some were proved to be partly consistent: locational factors inducing decentralized manufacturing into the suburb were proved to be inconsistent. I think that the results of previous studies on the other areas can be applicable to the explanation on the decentralization of Metropolitan manufacturing from the viewpoint of the suburb. For the better explanation on the decentralization of Metropolitan manufacturing, more empirical case studies on the suburbanization of manufacturing are necessary.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.4
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• pp.456-463
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• 1996

The purpose of the present study is to estimate the regional and seasonal variations of dissolved inorganic nitrogen (DIN) flux across the sediment-water interface of the inner and central areas of Hiroshima Bay from August 1994 to May 1995. In addition it compares the measured methods and estimates the effect of DIN released from sediment to the primary production of Hiroshima Bay. One method used in this study is to calculate DIN flux from a concentration gradient between sediment porewaters and the overlying water, and the other method is to measure DIN flux from the sediment-core experiment. The fluxes of $NH_{4}^{+}-N\;and\;NO_{2}^{+}\;+\;NO_{3}^{-}-N$ in the inner area were higher than those in central area, all of which showed seasonal variation. $NH_{4}^{+}-N$ flux was maximum in August, while $NO_{2}^{-}\;+\;NO_{3}^{-}-N$ flux was high in January compared with the other seasons. The calculated $NH_{4}^{+}-N\;and\;NO_{2}^{-}+NO_{3}^{-}-N$ fluxes from sediments were $18.2\~60.8\;{\mu}g-at/m^2{\cdot}hr\;and\;0.24\~18.2\;{\mu}g-at/m^2{\cdot}hr$, respectively. The measured $NH_{4}^{+}-N\;and\;NO_{2}^{-}+NO_{3}^{-}-N$ fluxes across the sediment-water interface were $2.00\~111\;{\mu}g-at/m^2{\cdot}hr\;and\;-265\~82.9\;{\mu}g-at/m^2{\cdot}hr$, respectively. The former was lower than the tatter. The calculated $NH_{4}^{+}-N$ flux showed closer relation to environmental factors (dissolved of gen in the overlying water, temperature and redox condition of the sediments) than the measured one did. On the other hand, in the case of $NO_{2}^{-}+NO_{3}^{-}-N$ flux both the calculated and the measured showed little relation to environmental factors, while they turned out to have stronger relation with their concentration in sediments. DIN released from the sediment is expected to support about $25\%\~67\%$ of the primary production in Hiroshima Bay.

• 한국해양학회지
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• v.8 no.1
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• pp.33-45
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• 1973

Plankton samples used for the present study were collected by the NORPAC net during the CSK cruises in the Korean waters in March and August, 1967. Regional and seasonal variations in the zooplankton biomass (wet weight, mg/㎥) were noticed in the Korean waters. In March the highest biomass, 130mg/㎥ on the average, occurred in the southern part of Japan Sea, but the lowest biomass of less than 50mg/㎥ occurred in the Yellow Sea and the western sea of Cheju Island Contrally, in August, the average biomass of 120mg/㎥ was measured in the Yellow Sea, the western sea of Cheju Island and the coastal waters of southern Korea, while the biomass of Japan Sea was the lowest of the regions surveyed. In comparison with the zooplankton biomass, total number of zooplankton per cubic meter of water strained also showed regional and seasonal fluctuations. In general, variations in the number of zooplankton specimens follows the same trend as in the biomass. The largest number, up to 800mg/㎥ on the average, occurred in the southern part of Japan Sea in March and the lowest number, less than 200mg/㎥ occurred in the Yellow Sea and the western sea of Cheju Island. In August, as shown by the biomass fluctuations, the largest number of zooplankton 850mg/㎥ on the average occurred in the Yellow Sea, the western sea of Cheju Island and the coastal region of southern Korea. But the lowest number of less than 500mg/㎥ was found in the Japan Sea. Among the various groups of zooplankton examined, the following were dominant components of the zooplankton population: Copepoda, Chaetognatha, Siphonophora, Euphausiacea, Cladocera, Appendicularia, and Amphipoda. The zooplankton conposition was significantly differed between the Japan Sea and Yellow Sea. Copepods which usually occupied over 66% in the Japan Sea and thd Korean Strait samples occupied only 42% of the catches in August, while cladocerans and chaetognaths were relatively abundant, i. e., 15 and 18% of the total organisms. The most dominant species of copepods and chaetognaths were Paracalanus parvus, Oithona similis, Acartia clausi, Calanus helgolandicus, Sagitta enflata, S. bedoti, S. elegans and S. crassa.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.418-430
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• 2017

The quality of surface water is a very important issue to use various demands like as drinking water, industrial, agricultural and recreational usages. There has been an increasing demand for monitoring water quality of many rivers by regular measurements of various water quality variables. However precise and effective monitoring is not enough, if the acquired dataset is not analyzed thoroughly. Therefore, the aim of this study was to estimate differences of seasonal and regional water quality using multivariate data analysis for each investing tributaries in Han River. Statistical analysis was applied to the data concerning 11 mainly parameters (flow, water temperature, pH, EC, DO, BOD, COD, SS, TN, TP and TOC) for the time period 2012~2016 from 12 sampling sites. The seasonal water quality variations showed that each of BOD, TN, TP and TOC average concentration in spring and winter was higher than that of summer and fall, respectively. In summer each flow rate and average concentration of SS was higher than any other seasons, respectively. The correlation analysis were explained that EC had a strong relationship with BOD (r=0.857), COD (r=0.854), TN (r=0.899) and TOC (r=0.910). According to principal component analysis, five principal components (Eigenvalue > 1) are controlled 98.0% of variations in water quality. The first component included TP, DO, pH. The second component included EC, TN. The third component included SS. The fourth component included flow. The last component included Temp. Cluster analysis classified that spring is similar to fall and winter with water quality parameters. AnyA, WangsA, JungrA and TancA were identified as affected by organic pollution. Cluster analysis derived seasonal differences with investigating sites and better explained the principal component analysis results.

• Economic and Environmental Geology
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• v.56 no.2
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• pp.139-153
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• 2023

This study aimed to understand the spatiotemporal variations in nitrogen content in the Gyeongan stream along the main stream and at the discharge points of the sub-basins, and to identify the origin of the nitrogen. Field surveys and laboratory analyses, including chemical compositions and isotope ratios of nitrate and boron, were performed from November 2021 to November 2022. Based on the flow duration curve (FDC) derived for the Gyeongan stream, the dry season (mid-December 2021 to mid-June 2022) and wet season (mid-June to early November 2022) were established. In the dry season, most samples had the highest total nitrogen(T-N) concentrations, specifically in January and February, and the concentrations continued to decrease until May and June. However, after the flood season from July to September, the uppermost subbasin points (Group 1: MS-0, OS-0, GS-0) where T-N concentrations continually decreased were separated from the main stream and lower sub-basin points (Group 2: MS-1~8, OS-1, GS-1) where concentrations increased. Along the main stream, the T-N concentration showed an increasing trend from the upper to the lower reaches. However, it was affected by those of the Osan-cheon and Gonjiamcheon, the tributaries that flow into the main stream, resulting in respective increases or decreases in T-N concentration in the main stream. The nitrate and boron isotope ratios indicated that the nitrogen in all samples originated from manure. Mechanisms for nitrogen inflow from manure-related sources to the stream were suggested, including (1) manure from livestock wastes and rainfall runoff, (2) inflow through the discharge of wastewater treatment plants, and (3) inflow through the groundwater discharge (baseflow) of accumulated nitrogen during agricultural activities. Ultimately, water quality management of the Gyeongan stream basin requires pollution source management at the sub-basin level, including its tributaries, from a regional context. To manage the pollution load effectively, it is necessary to separate the hydrological components of the stream discharge and establish a monitoring system to track the flow and water quality of each component.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.1
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• pp.44-51
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• 2008

Purpose: We performed this study to evaluate reliability on interpretation of three phase bone scintigraphy (TPBS) in patients with post-traumatic complex regional pain syndrome (PT-CRPS). Methods: Based on International Association for the Study of Pain guideline in 1994, 34 patients with PT-CRPS were selected for this study. Two nuclear medicine physicians evaluated identical TPBS according to the uptake pattern, extent and intensity of the lesion, and their agreements (kappa values) were analysed. The final diagnosis based on arbitrary criteria of each physician were compared with those obtained by the criteria for PT-CRPS established in this study, which are hyperactivity on all phases (criteria 1), hyperactivity of whole joints on delayed phase (criteria 2), and hyperactivity of either whole or FDGal joints on delayed phase (criteria 3). Results: Intra-observer agreements were good for uptake pattern, intensity, and extent on TPBS. Inter-observer agreements were also good, except extent on blood pool phase (0.55). The inter-observer agreements on final diagnosis improved when criteria 1-3 were applied (0.77-0.88), compared to when physician's own criteria were used (0.63). Those also improved from 0.29 to 0.47-0.82 for acute stage, and from 0.37 to 1.0 for chronic stage. The sensitivities of chronic stage were relatively lower to those of acute stage. Conclusions: Inter-observer's variations in diagnosis of the patients with PT-CRPS using TPBS were observed. These results were attributed to different criteria set by observers. In order to improve agreement on interpretation of TPBS, common positive criteria should be established, especially considering uptake pattern and clinical stages.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.257-268
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• 1990

The regional characteristics in the occurrence of the rice stem borer, Chilo suppressalis (Walker), in Korea, were examined by analyzing the light trap data obtained from 39 locations during the years of 1965-1988, and some ecological significance of the overwintering larval populations collected from the four locations where some of the typical ecological-race have been known, the results obtained are as follows; The total number of the moths have decreased greatly throughout the nation since 1970. The decrease in the total number of moths related with those in the spring moth but not in the summer moths, and suggested that the changes in the rice production systems have effected significantly on the second generation of the insect. The variations between the regions had been gret in 1960's, decreasing phase in 1970's and increasing phase in loast decade. The overall average of 50% emergence dates have shifted earlier in both moths, and the changes were different considerably with the regions as wheel as in generations. When the overwintered larvae were incubated at $25^{\circ}C$ and RH of 90%, the average mortalities were 21.07% for Suweon, 43.06% for Iri, 63.51% for Jinju, 27.04% for Gwangju. When the overwintered larvae were incubated at $25^{\circ}C$ and RH of 90%, the average mortalities were different with the body weight; 45.44% for the larvae of less than 39 mg, 37.61% for 40-49 mg, 37.28% for 50-59 mg, 30.17% for greater than 60 mg. When the overwintered larvae wee incubated at $25^{\circ}C$, post-diapause larval development periods of body weight classes were 18.6$\pm$1.2 days for the larvae of less than 39 mg, 20.4$\pm$3.3 days for 40-49 mg, 21.4$\pm$3.2 days for 50-59 mg, 21.8$\pm$3.2 days for grater than 60 mg, and only the larvae of less than 39 mg, body weight class less than 39 mg was found statistically different in post-diapause larval development periods. From these results, the changes in the cultural practice of the rice have effected on the ecological pattern of the rice stem borer, and the effects seemed to be different with the generations, and with the regions where the different ecological races are distributing.

• Journal of Chest Surgery
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• v.36 no.3
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• pp.182-188
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• 2003

Background: Although ramicotomy (division of the rami communicantes of the thoracic sympathetic ganglia) is a selective and physiological surgical method for essential hyperhidrosis, it has some problems such as higher recurrence rates and the different surgical results among the patients and between left and right sides in the same individual. As one of the factors that are related to the differences in surgical result and recurrences, we investigated the anatomical variations of the rami communicantes. The purpose of this study is to help develop new surgical methods to decrease surgical differences among the patients or between the left and right sides of the same individual and recurrence rates in the clinical application of ramicotomy. Material and Method: We dissected 118 thoracic sympathetic chains in 59 adult Korean cadavers (male: 33, female: 26) to examine the anatomical variations of the rami communicantes from the second to the fourth thoracic sympathetic ganglia that have major components innervating to the hands. After the dissection of bilateral thoracic sympathetic chains, we compared the anatomy of left and right sides and examined the anatomical variations of rami communicantes. Result: The number and variation of communicating rami connecting the spinal nerves and the second sympathetic thoracic ganglion were much larger than lower levels. There was considerably less variability in the anatomy of the rami communicantes at successive levels. Among the 59 cadavers dissected, only 14.3% (9/59) had similar anatomy of thoracic sympathetic chains at both sides. As the components related to the essential palmar hyperhidrosis, intrathoracic nerve of Kuntz from the second thoracic sympathetic ganglion to the first intercostal nerve or brachial plexus were observed in 55.9% (66/118). The incidence of descending rami communicates from the second thoracic sympathetic ganglion to the third intercostal nerve and from the third thoracic sympathetic ganglion to the fourth intercostal nerve were 49.2% (58/118) and 28.0% (33/118). And the incidence of ascending rami communicates from the third thoracic sympathetic ganglion to the second intercostal nerve and from the fourth thoracic sympathetic ganglion to the third intercostal nerve were 6.8% (8/118) and 3.4% (4/118), respectively. Conclusion: Based on the various anatomical evidences of the rami communicantes from this study, only the ramicotomy at the third sympathetic ganglion level is insufficient for the treatment of the essential palmar hyperhidrosis to decrease the difference of surgical results and recurrences. When one is planning to perform the ramicotomy for the essential palmar hyperhidrosis, it is advantageous to divide the intrathoracic nerve of Kuntz on the second rib and the descending or ascending rami communicantes on the third and the fourth ribs as well as all the communicating rami from the third sympathetic ganglion.

• Journal of the Korean Geographical Society
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• v.40 no.5 s.110
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• pp.514-532
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• 2005

The purpose of this study is to critically examine conventional spatial measures of individual accessibility, which are based on the notion of spatial proximity, the single reference location, and the unlinked travel model. Using space-time accessibility measures with the travel-activity diary data set of Portland Metro, US, three expectations from spatial measures on spatial patterns of individual accessibility were empirically examined: (1) does individual accessibility decrease with an increase of distance from the CBD?; (2) does the spatial pattern of accessibility resemble that of urban opportunity density pattern?; and (3) are spatial patterns of individual accessibility of different socio- demographic population groups basically similar as people in the same area share the same geographic characteristics regardless of gender, race, age, and so on? First of all, the results showed that spatial variations in individual accessibility were not directly determined by spatial proximity and opportunity density as suggested by previous accessibility measures. The spatial pattern of individual accessibility was dramatically different from that of urban opportunity density High peaks of accessibility level were found far away from the CBD and regional centers. This finding might be associated with the importance of multi-reference locations and linked travels in shaping accessibility in reality. Furthermore, this study found that spatial patterns of accessibility clearly differ between men and women. These findings suggest that access requires more than proximity, and that the interaction between person-specific space-time constraints and the consequential availability of urban opportunities in space-time renders different accessibility experiences to people even in the same region, which would be one of the key ingredients missing from conventional spatial measures of accessibility.