http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Cicada Population Density is Correlated with the Urban Heat Island Effect in Metropolitan Seoul
Nguyen Quynh Hoa,Jang Yikweon 한국응용곤충학회 2016 한국응용곤충학회 학술대회논문집 Vol.2016 No.04
In Korea, Cryptotympana atrata and Hyalessa fuscata are the most abundant cicada species, and their population densities were 2.8-9.5 times higher in urban areas than in rural areas. It has been suggested that the urban heat island effect (UHI), which is higher temperatures in urban areas than in surrounding areas due to human activities, underlied the population density differences between urban and rural areas. To elucidate the relationship between UHI and cicada population density, we compared cicada population densities in three groups: areas of high and low UHI in metropolitan Seoul as well as areas in the vicinity of Seoul. C. atrata and H. fuscata constituted almost 30% and 70% of the exuviae, respectively, collected across all sampling localities. Moreover, no difference in species composition was observed among groups. The densities of C. atrata and H. fuscata were 14 and 41 times higher in high UHI areas than in low UHI areas. Furthermore, the degree of UHI was significantly correlated with densities of both C. atrata and H. fuscata. In summary, these results support that higher temperatures during the development may cause population increases of C. atrata and H. fuscata.
Description of advertisement songs in three cicada species of Korea
Nguyen Quynh Hoa,Yikweon Jang 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.10
Advertisement songs play an important role on species recognition and mate choice in cicadas. Males generate complex species-specific calling songs to attract conspecific females. In central Korea, Cryptotympana atrata, Meimuna mongolica and Hyalessa fuscata are widely distributed, yet their songs have not been described. We analyzed acoustic characteristics of these cicadas’ advertisement songs in temporal and spectral domains. In sum, C. atrata’s songs followed the pulse-echeme pattern, in which each echeme consisted of groups of pulses with the peak frequency of 6423 ± 589 Hz. In M. mongolica, the calling song had the pulse-echeme-combined echeme-phrase structure. A group of three echemes formed one combined echeme, and one full phrase comprised hundreds of combined echemes. Lastly, the calling song of H. fuscata was constructed of the pulseecheme- phrase structure, in which one full phrase included a train of low and high-frequency echemes and the ending echeme at the end of the phrase. The carrier frequency of low frequency echeme was 4576 ± 151 Hz and that of high frequency one was 14089 ± 628 Hz.
Comparative thermal responses of two cicada species in metropolitan Seoul
Nguyen Quynh Hoa,BaeYoonhyuk,Kim Yeinn,Jeong Hyunsoo,Chae Soyeon,Ha Jeongju,Ji Seongmin,Heo Kyungman,Heo Jiman,Jang Yikweon 한국응용곤충학회 2017 한국응용곤충학회 학술대회논문집 Vol.2017 No.04
UHI rises when urban area becomes warmer than its surrounding and is considered as one of the main reasons for cicada abundance in urban areas. Two cicada species, Cryptotympana atrata and Hyalessa fuscata, are more abundant in urban areas with high urban heat island intensities (UHI) than in areas with low UHI. Thermal responses are a measure of cicada adaptation to thermal conditions in the habitat. Hence, we hypothesized that cicadas inhabiting high UHI areas exhibited elevated thermal responses compared to those occupying in low UHI areas. We measured minimum flight temperature (MFT), maximum voluntary temperature (MVT), and heat torpor temperature (HTT) of C. atrata and H. fuscata in metropolitan Seoul. For each species, there were three treatments: high UHI, low UHI, and suburb populations. We discovered that MFT and MVT were similar across all thermal treatments for each species. There was no difference in HTT across three treatments in C. atrata, meanwhile the HTT estimate was significantly higher in H. fuscata with high UHI than in those with low UHI. These results may suggest that H. fuscata in areas of high UHI may have developed thermal adaptation to high temperatures.
An effective method for accurate nymphal-stage delimitation of the cicada Hyalessa fuscata
Hoa Quynh Nguyen,Erick Kim,Yoonhyuk Bae,Soyeon Chae,Ji Seongmin,Jiman Heo,Sungsik Kong,Thoa Kim Nguyen,Hong Pham Thai,장이권 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.3
Subterranean nymphal development in cicadas presents challenges to researchers in accurately estimating the number of their developmental stages, although such information is crucial to understanding and predicting their population dynamics. While most studies have relied on head width as an attribute for life-stage determination to date, such character in cicadas can be highly variable and thus differentiation solely based on such morphology is prone to subjectivity in practice. Here, we propose a reliable method for instar estimation that is applicable to Hyalessa fuscata nymphs. We first obtained morphometrics of nymphs in all stages. Second, we computed logarithm-transformation and principal component analysis to extract a transformed variable that captures most of the variance of morphological characteristics. Third, k-means were computed to divide the dataset into distinct clusters assuming four-, five- and six life-stage scenarios for the best interferences of life stages. Finally, simple linear regression analysis was conducted to compare and select the best fit model. Our result shows that five nymphal stages best fit for H. fuscata nymphs. This method is expected to provide an easy-to-handle ecological tool for the study of life history of cicadas as well as other insects that have long life cycles and multiple developmental stages.
Cung Huu NGUYEN,Thi Truc Quynh PHAM,Thi Hoa TRAN,Thi Hoa NGUYEN 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.11
Foreign capital inflows play an essential role in each country’s socio-economic growth, particularly for undeveloped and developing countries where capital accumulation is limited in the early stages of development, and Vietnam is no exception. The purpose of this article is to examine the impact of foreign capital inflows on economic growth in Vietnam. The empirical method employed secondary time-series data set during the period 1995–2018 to determine the impact of FDI, foreign aid, foreign loans, and exports on economic growth in Vietnam by using a linear approach. For this study, data was collected from the World Bank and relevant agencies in Vietnam. The results show that FDI (net inflows), foreign aid, foreign loans, exports, and GDP (current), have a positive effect at a 1% significance level on economic growth. Rather, an increase in FDI (net inflows), foreign aid, foreign loans, exports has beneficial effects on the Vietnamese economy in the study period. Based on the findings of this study, the article proposes several important policy implications for Vietnam in maintaining a high rate of economic growth via the contribution of FDI inflows, foreign aid, foreign loans, and exports.
Acoustic competition in the multi-species cicada choruses
Yikweon Jang,Jae Yeon Kang,Nguyen Quynh Hoa 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.10
Five species of the subfamily Cicadinae are typically found in urban areas of central Korea, including Cryptotympana atrata, Graptopsaltria nigrofuscata, Hyalessa fuscata, Meimuna mongolica, and Meimuna opalifera. These species form multi-species choruses. We hypothesized that there is a negative relationship between dominance of choruses among cicada species. We tested this hypothesis by conducting the 24-h recording experiments in four localities: Gawcheon, Jamsil, Ewha University, and Yangpyeong. Based on the enumeration surveys of exuviae, the results of 24-h recordings showed that choruses of C. atrata and H. fuscata were negatively correlated with other in Jamsil and Ewha University, but were positively correlated with other in Gawcheon and Yangpyeong. Thus, it seemed unclear cicada species competed with each other negatively over. Males of C. atrata produced calling songs usually during the day at temperatures typically higher than 28 C°. However, males of H. fuscata produced calling songs throughout the day at a wide range of temperatures. As a result, the chorus of C. atrata dominated during the day, but that of H. fuscata in urban areas where the densities of C. atrata were sufficiently high.
( Nguyen Thai Son ),( Vu Thi Thu Huong ),( Vu Thi Kim Lien ),( Do Thi Quynh Nga ),( Tran Thi Hai Au ),( Tang Thi Nga ),( Le Nguyen Minh Hoa ),( Tran Quang Binh ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.9
The extensive distribution of multidrug-resistant (MDR) methicillin-resistant Staphylococcus aureus (MRSA) poses a threat to healthcare worldwide. This study aimed to investigate the MDR and molecular patterns of MRSA isolates in children admitted to the two biggest tertiary care pediatric hospitals in northern and southern Vietnam. A total of 168 MRSA strains were collected to determine antibiotic susceptibility by minimum inhibitory concentration tests. Antibiotic-resistant genes, pulsed-field gel electrophoresis, staphylococcal cassette chromosome mec (SCCmec) typing, and multilocus sequence typing were used for the molecular characterization of MRSA. Among the total strains, the MDR rate (51.8%) was significantly higher in the northern hospital than in the southern hospital (73% vs. 39%, p < 0.0001). The MDR-MRSA with the highest rates were “ciprofloxacin-erythromycin-gentamicin-tetracyclines” (35.6%), followed by “erythromycin-tetracycline-chloramphenicol” (24.1%), and “ciprofloxacin-erythromycin-gentamicin” (19.5%), showing an accumulative total of 79.3%. The most susceptible antibiotics were rifampicin (100%) and vancomycin (100%), followed by doxycycline (94.0%), meropenem (78.0%), and cefotaxime (75.0%). The SCCmecII strains showed greater resistance to gentamicin, ciprofloxacin, tetracycline, meropenem and cephalosporins compared with the other strains. The SCCmecII strains exhibited the highest rate in the tested genes (aacA/aphD: 55.2%, ermA/B/C: 89.7%, and tetK/M: 82.8%). ST5-SCCmecII was the predominant clone in the northern hospital, whereas SCCmecIVa was more pronounced in the southern hospital. In conclusion, our results raised concerns about the predominant MDR-MRSA strains in the pediatric hospitals in Vietnam. The north-south difference in the antibiotic resistance patterns and genetic structure of MRSA suggests different MRSA origins and various uses of antimicrobial agents between the two regions.