Understanding the Visitation Aspect of Black-headed Gull (Larus ridibundus) in the Long Period at Nakdong Estuary, Busan, Republic of Korea

AbstractThis study analyzes data in the first half of 1990 (May, 1989 - April, 1993) and mid-2000 (May, 2002 - April, 2006) to understand long-term status of black-headed gulls (Larus ridibundus) in the estuary of the Nakdong River under rapid changes. During the period (May, 1989 - April, 1993 and May, 2002 - April, 2003 for a total of 8 years), a total of 201,519 individuals of Laridae were discovered at the estuary and the number of the black-headed gulls (Larus ridibundus) was 32,538 (16.15%). Monthly average of the black-headed gulls showed that there were just a small number of individuals arrived in July and August, but the number increased from September, reached the highest in April for the first term (1989 - 1993). The second term showed that some individuals were discovered in summer (June - August), then the number increased from October and reached the peak in April. Monthly average in the latter period marked 5.7 times higher than that of the former. In the aspect of individuals, there is a significant difference between the two period (P<0.05) and it is discovered that the number of individuals in 2000s (Mean= 6923.50) was higher than that of 1990s (Mean=1211.00). Comparing individuals of gulls, herring gulls (Larus argentatus) and black-headed gulls for 8 years, it was found out that the herring gulls (Larus argentatus) showed the largest number (average=5313.13), followed by the black-headed gulls (average=4067.25) and gulls (average= 1207.63). The fluctuation on individuals of black-headed gulls in the mid-2000s (May, 2005 - April, 2006) recorded the average number of 472.75, then 113.50 in DMD, 244.00 in JJ and SJD, 635.25 in SJ and DY, 727.50 in LUD and 643.50 in USD, showing significant differences among regions (P<0.05)

Education Policy and Industrial Development: The Cases of Korea and Mexico

After many scholars studies, it has been suggested that among several facts of economic growth, Koreas relatively intensive investment in education made its fast economic growth possible. This study started from the question of whether large education expenditure automatically leads to a fast economic growth. We suggest that the expenditure must be allocated to the education level that is in accordance with the industrial policy, which in turn must consist with the countrys economic development stage. In Korea, the education sector supplied workers with adequate level of education that was required in each stage of development, whereas in Mexico, the supply of workers by education level was mismatched with the demand for labor derived from the industrial structure at each development stage. We conclude that not only the size of the expenditure but also its efficient use is important to guarantee the positive effects of education expenditure on economic growth

Bonghan Ducts as Possible Pathways for Cancer Metastasis

Objective: The present study has been designed to find a possible new route for the metastasis of cancer cells on the fascia surrounding tumor tissue using a novel technique of trypan blue staining. Materials and Methods: Tumor tissues were grown in the skin of nude mice after subcutaneous inoculation with human lung cancer cells. Trypan blue was recently identified as a dye with specificity for Bonghan ducts (BHDs) and not other tissues, such as blood or lymph vessels or nerves. Results: We demonstrate that the trypan blue staining technique allows the first visualization of BHDs which are connected to tumor tissues

Bonghan Ducts as Possible Pathways for Cancer Metastasis

Objective: The present study has been designed to find a possible new route for the metastasis of cancer cells on the fascia surrounding tumor tissue using a novel technique of trypan blue staining. Materials and Methods: Tumor tissues were grown in the skin of nude mice after subcutaneous inoculation with human lung cancer cells. Trypan blue was recently identified as a dye with specificity for Bonghan ducts (BHDs) and not other tissues, such as blood or lymph vessels or nerves. Results: We demonstrate that the trypan blue staining technique allows the first visualization of BHDs which are connected to tumor tissues