• 유통과학연구
• /
• 제11권4호
• /
• pp.5-11
• /
• 2013

Purpose - The aim of this work is to study the reorientation that the export industrial sectors in Costa Rica have experienced during the last 20 years. Research design, data, methodology - The study employs the Cluster Analysis with the export data (20 years of cut-off period) from Costa Rica to the U.S-market. To make the predictions, the technique of the time series was used, with official data (from 2001 to 2010) from the U.S. Department of Commerce and the U.S. International Trade Commission. Results - The Cluster Analysis, show how the economic sectors of traditional products exports of Costa Rica have progressively become in exporters of non-traditional products, meanwhile,the time series confirms that this trend will continue, at least during the next five years. Conclusions - The industry of traditional products exports of Costa Rica (dressmaking, vegetables, coffee, mate, species, etc.) will progressively become in exporters of non- traditional products with a high-tech component (i.e., mechanical equipment and devices, electronic devices and medical equipment),as a consequence of the Chinese (Costa Rica's main competitor) economy's presence in the Organization for Economic Co-operation and Development (OCDE). This fact has enabled the potential improvement of Costa Rica's international competitiveness in the U.S. market.

• The Plant Pathology Journal
• /
• 제29권3호
• /
• pp.285-293
• /
• 2013

Leaf samples of Solanum lycopersicum, Capsicum annuum, Cucurbita moschata, Cucurbita pepo, Sechium edule and Erythrina spp. were collected. All samples were positive for begomoviruses using polymerase chain reaction and degenerate primers. A sequence of ~1,100 bp was obtained from the genomic component DNA-A of 14 samples. In addition, one sequence of ~580 bp corresponding to the coat protein (AV1) was obtained from a chayote (S. edule) leaf sample. The presence of Squash yellow mild mottle virus (SYMMoV) and Pepper golden mosaic virus (PepGMV) were confirmed. The host range reported for SYMMoV includes species of the Cucurbitaceae, Caricaceae and Fabaceae families. This report extends the host range of SYMMoV to include the Solanaceae family, and extends the host range of PepGMV to include C. moschata, C. pepo and the Fabaceae Erythrina spp. This is the first report of a begomovirus (PepGMV) infecting chayote in the Western Hemisphere.

• Wind and Structures
• /
• 제35권2호
• /
• pp.121-130
• /
• 2022

In this paper, the issue of pitch control in a vertical axis wind turbine was tackled. Programming the Actuator Cylinder model in MATLAB, a theoretical optimum pitch solution was found and then a classic four-bar mechanism was adapted to that theoretical solution to achieve a simple and elegant control of the pitch in the turbine. A simulation using the mechanism worked to find the optimum pitch cycles, where it was found that the mechanism would, in fact, increase the efficiency of the VAWT, by at least 11% and in the best case, over 35%. Another aspect that is studied is the possibility of self-start of the turbine by only changing the pitch on the blades. This analysis, however, proved that a further individual pitch control must be used to surpass the cogging torque. All analyses conducted were done for a specific wind turbine that is 2 m² in the swept area.

• Imaging Science in Dentistry
• /
• 제48권2호
• /
• pp.103-109
• /
• 2018

Purpose: To analyze cone-beam computed tomography (CBCT) use, indications, and exposure parameters in San $Jos{\acute{e}}$, Costa Rica. Materials and Methods: A cross-sectional study was performed. All CBCT examinations over a period of 6 months at 2 radiological centers in San $Jos{\acute{e}}$, Costa Rica were evaluated. The examinations were performed with Veraview EPOC X550 and Veraviewepocs 3D R100 equipment. The patients' age and sex, clinical indication for CBCT, region of interest (ROI), repeat examinations, specialty of the referring dentist, field-of-view (FOV), tube voltage (kV), tube current (mA), and radiation dose (${\mu}Gy$) were evaluated. Patients were classified by age as children (${\leq}12years$), adolescents(13-18 years), and adults(${\geq}19years$). Results: The mean age of the 526 patients was 49.4 years. The main indications were implant dentistry and dental trauma. The most frequent ROIs were posterior, while anterior ROIs were much less common. The highest percentage of repeat examinations was in children. Fifty-six percent of the referring dentists were specialists. The most commonly used FOV was small. The mean tube voltage and current were 79.8 kV and 7.4 mA for Veraview EPOC X550 and 89.9 kV and 6 mA for Veraviewepocs 3D R100, respectively. The mean doses for children, adolescents, and adults were $6.9{\mu}Gy$, $8.4{\mu}Gy$, and $7.8{\mu}Gy$, respectively. Conclusion: Although CBCT was most commonly used in adults for implant dentistry, most repeat examinations were in children, and the highest mean dose was in adolescents. Additional dose optimization efforts should be made by introducing low-dose protocols for children and adolescents.

• ALGAE
• /
• 제28권1호
• /
• pp.63-71
• /
• 2013

Lithothamnion muelleri is reported for the first time as one of the main components of rhodolith beds along the Eastern Pacific Ocean based on samples from Washington State (USA), Pacific Baja California (M$\acute{e}$xico), southern Nicaragua, and Costa Rica. Individual rhodoliths ranged from fruticose to lumpy in morphology, and bi-sporangial, tetrasporangial, and gametangial plants were similar to those described from Australia and Brazil. Our study revealed a surprisingly wide latitudinal distribution of this species along the American continent. Its documentation in the Eastern Pacific will facilitate a more accurate interpretation of the ecology, biology, and biogeography of rhodolith beds worldwide.

• 한국작물학회지
• /
• 제67권4호
• /
• pp.285-295
• /
• 2022

The trapping efficacy of five commercially available sex pheromones manufactured in Korea, the Netherlands, North America, China, and Costa Rica was evaluated to determine the population dynamics of Spodoptera frugiperda and Mythimna loreyi and their relationships with the weather parameters of maize fields in Miryang, Gyeongnam Province, Korea in 2019. The results show that the sex pheromone manufactured in Costa Rica were more efficient at capturing S. frugiperda and M. loreyi than those manufactured in other countries. The lowest number of S. frugiperda moths were captured using sex pheromones manufactured in the Netherlands. We noted that more than four population peaks of both the moth species and weather parameters influenced the moth population dynamics in Miryang. A positive relationship was observed between the population of S. frugiperda and weather parameters, such as mean temperature, rainfall, and relative humidity, for sex pheromones manufactured in Korea. Furthermore, a positive relationship was recorded between the population of M. loreyi and wind speed for the sex pheromone manufactured in Korea. The results of this study suggest that the sex pheromones manufactured in Costa Rica are the best solution for the efficient capture of S. frugiperda and M. loreyi under typical weather conditions in the southern parts of Korea. In addition, the outcomes of this study are discussed in terms of population dynamics and integrated pest management for S. frugiperda and M. loreyi as alternatives to chemical management by maize producers. Further studies related to the continuous improvement in the capture efficiency of both moth species using sex pheromones are now needed.

• Journal of Applied Biological Chemistry
• /
• 제63권1호
• /
• pp.9-22
• /
• 2020

이 연구는 농산물의 원산지에 따른 검출 농약을 조사하여 대한민국의 수입 바나나 중 잔류농약 안전 관리 자료로 활용하고자 하였다. 미국, 일본, EU, 영국 및 대한민국의 2007에서 2018년까지 바나나 중 잔류농약 검사 결과를 활용하여 검출 농약, 검사 건수, 농약 검출 건수 및 검출량으로 정리하였다. 이들 바나나의 잔류농약 검사에서 검출된 농약은 총 109종이었으며, 전체 검사 건수는 206,894건이었다. 이 중 9,483건에서 잔류농약이 검출되었으며, 농약 검출률은 4.58%였다. 검출된 농약은 chlorpyrifos, imazalil, methyl-bromide, azoxystrobin, carbendazim, pretilachlor 및 thiabendazole 등 이었으며, 이 농약들의 검출률은 10.62-24.62% 범위였다. Chlorpyrifos가 검출 건수에서 가장 많이 검출되었으며, 다음으로 imazalil, azoxystrobin, thiabendazole, bifenthrin 및 carbendazim 순이었다. EU, 일본, 미국, 영국 및 대한민국의 잔류농약 검사에서 각각 85, 57, 23, 18 및 8종 농약이 검출되었다. Azoxystrobin, bifenthrin 및 chlorpyrifos는 모든 국가의 모니터링에서 검출되었다. 코스타리카 및 에콰도르산 바나나에서 각각 14 및 12종 농약이 검출되었다. Imazalil 및 thiabendazole은 각각 16 및 11개 원산지에서 검출되었다. Myclobutanil 및 iprodione은 각각 4 및 2개국산에서 검출되었다. Azoxystrobin 및 bifenthrin은 코스타리카산 바나나에서 각각 11.8 및 9.8% 검출 건수를 보였고, azoxystrobin의 검출률은 콜롬비아산에서 19%였다. 벨리즈산, 콜롬비아산 및 코스타리카산 바나나 중 chlorpyrifos는 각각 22.7, 13.3 및 10.8%의 검출률을 보였고, 콜롬비아산 및 코스타리카산 바나나 중 myclobutanil의 검출률은 각각 17.9 및 10.4%였다.

• 한국지역사회생활과학회지
• /
• 제24권1호
• /
• pp.5-12
• /
• 2013

Caffeine is an alkaloid of the methylxanthine family known as a central nervous system stimulant, temporarily warding off drowsiness and restoring alertness in humans. There is a recommended upper limits of caffeine for health because a high dose can cause negative effects. Chlorogenic acid is a natural polyphenol compound known to have an antioxidant activity. In this study, the contents of caffeine and chlorogenic acid in coffee beans from different origins(Costa Rica, Indonesia, Vietnam) were determined by using liquid chromatography-tandem mass spectrometry(LC-MS/MS). The experiment offers more selectivity and sensitivity for those compounds compared with conventional methods such as UV/VIS spectrophotometry. The average concentrations of caffeine and chlorogenic acid in coffee beans origined in Costa Rica were 15.05 mg/g and 5.33 mg/g respectively. In the case of coffee beans origined in Indonesia, the average concentrations were 13.10 mg/g for caffeine and 3.75 mg/g for chlorogenic acid. Vietnamese coffee showed that the average concentrations were 17.79 mg/g for caffeine and 1.12 mg/g for chlorogenic acid. This study can contribute to a better understanding of the contents of caffeine and chlorogenic acid in various coffee beans in order to evaluate dietary intake.

• Animal cells and systems
• /
• 제1권4호
• /
• pp.577-581
• /
• 1997

Species diversity of subcortical arthropod communities were assessed in two tropical regions and two temperate regions. In the tropics, communities of subcortical arthropods were more diverse in La Selva, Costa Rica, than on Barro Colorado Island, Panama. Costa Rican communties yielses higher values of both Shannon and Simpson diversity indices than Panamanian communities. Compared to Panamanian communities, Costa Rican ones supported higher measures of both species richness and evenness. Between the two temperate regions, communities of subcortical arthropods in Korea scored consistently higher values of both Shannon and Simpson indices than the ones in eastern Massachusetts, U.S.A. When individual diversity components were compared, however, Korean communities yielded exceptionally high evenness measures but lower species richness than the communities in the U.S.A. Unusually high evenness values of Korean subcortical arthropods were due to extremely low population densities of all component species.

• 한국수산과학회지
• /
• 제17권2호
• /
• pp.143-150
• /
• 1984

1. 1981년 12월 22일에 조사한 니코야만의 기온은 $27{\sim}32^{\circ}C$였고, 수온은 $28{\sim}29.5^{\circ}C$, 염분농도는 표면과 5 m 층이 공히 $20{\sim}28.5\%$였다. 2. 용존산소량은 $7.3{\sim}9.95ml/l$ 범위로서 대체로 풍부한 편이었다. 3. 니코야만부근의 10년간 평균강우량은 Puntarenas 부근이 평균 $1298.6{\sim}2196.3mm$ 이며, 연내강우평균일수는 137.7일이며, $5{\sim}11$월의 우기에 대부분의 강우량을 나타내고 있다. 4. 한국의 굴 주산지인 충무부근의 강우량은 연간 1836.0mm로 비슷한 양이나 $11월{sim}2월$을 제하고는 대체로 비슷한 강우량을 나타내고 있다. 5. 12월 22일 니코야만에서 채집된 식물성프랑크톤의 출현종은 규조류 13속 16종, 편모조류 2속 3종이며 현존양은 $639{\sim}130,211\;cell/l$ 였고, 우점종은 Chaetoceros curvisetus, Chaetoceros decipiens, Nitzschia serata 등의 규조류였고 Thalassiothrix mediterranca는 Tropical Estuary에서 출현하는 것으로 보였다. 6. 니코야 만에서의 수온, 비중, 용존산소량등 수질상태로 보아 시험양식이 요망된다.