• 제목/요약/키워드: Tropical

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국립수목원 열대온실 내 인공배합토의 물리화학적 특성 및 식물 생육 변화에 관한 연구 (A Study on Physicochemical Properties of Artificial Substrates and Changes of Plant Growth in Tropical Plant Resources Research Center of Korea National Arboretum)

  • 송정화;진혜영;안태현
    • 한국환경복원기술학회지
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    • 제13권2호
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    • pp.52-62
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    • 2010
  • This study was carried out in the Tropical Plant Resources Research Center of Korea National Arboretum to determine the optimum edaphic environment for the growth of tropical and subtropical plants. The physicochemical properties of artificial substrates and the growth characteristics of tropical and subtropical plants were investigated. Subtropical plants exhibited a high growth rate when cultivated in a substrate of Dry Zone that had physical properties similar to those of arid native soil. Mediterranean plants showed a low growth rate when grown in a substrate of Subtropical Zone that required changes in acidity. The substrate of Tropical Zone had high organic matter and mineral contents and therefore had good physical properties:this substrate has a good environment for the stimulation of the growth of tropical plants. Our results indicate that the chemical properties such as pH and mineral contents of most artificial substrates need to be more urgently improved than their physical properties in order to ensure better growth of tropical and subtropical plants. Initial management strategies for the construction of new tropical greenhouses were formulated, and data from monitoring studies will be continuously gathered and incorporated in the manual to keep it updated.

Minor liver profile dysfunctions in Plasmodium vivax, P. malariae and P. ovale patients and normalization after treatment

  • Tangpukdee, Noppadon;Thanachartwet, Vipa;Krudsood, Srivicha;Luplertlop, Nutthanej;Pornpininworakij, Karnchana;Chalermrut, Kobsiri;Phokham, Sasikarn;Kano, Shigeyuki;Looareesuwan, Sornchai;Wilairatana, Polrat
    • Parasites, Hosts and Diseases
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    • 제44권4호
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    • pp.295-302
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    • 2006
  • Liver function tests were peformed in 61 vivax, 54 malariae and 15 ovale malaria patients who were admitted to Bangkok Hospital for Tropical Diseases between 2001 and 2004. The objective of the study was to evaluate changes in hepatic biochemical indices before and after treatment with artemisinin derivatives. On admission and prior to treatment, hepatic dysfunction was found among the 3 groups. Serum liver function tests and physical examinations were peformed weekly during the 28-day follow-up period. Initially elevated serum bilirubin and diminished albumin returned to normal within 2 weeks of treatment. Serum alkaline phosphatase and aminotransferases returned to within normal limits within 3 weeks. We conclude that patients with Plasmodium vivax, P. malariae and p. ovate infections had slightly elevated serum bilirubin, aminotransferase and alkaline phosphatase levels, and hypoalbuminemia. These minor abnormalities returned to normal within a few weeks after treatment with therapies based on artemisinin derivatives.

Prevalence and Alternative Treatment of Head-Lice Infestation in Rural Thailand: A Community-Based Study

  • Singhasivanon, On-uma;Lawpoolsri, Saranath;Mungthin, Mathirut;Yimsamran, Surapon;Soonthornworasiri, Ngamphol;Krudsood, Srivicha
    • Parasites, Hosts and Diseases
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    • 제57권5호
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    • pp.499-504
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    • 2019
  • Head-lice infestation, pediculosis capitis, remains a public-health burden in many countries. The widely used first-line pediculicides and alternative treatments are often too costly for use in poor socio-economic settings. Ivermectin has been considered an alternate treatment for field practice. This study was composed of 2 parts, a cross-sectional survey and an intervention study. The main objectives were to determine the prevalence and potential factors associated with head-lice infestation, and to evaluate the effectiveness and safety of oral ivermectin administration. A community-based cross-sectional survey was conducted among 890 villagers in rural areas along Thai-Myanmar border. Females with infestations were eligible for the intervention study, and 181 participated in the intervention study. A post-treatment survey was conducted to assess acceptance of ivermectin as a treatment choice. Data analysis used descriptive statistics and a generalized-estimation-equation model adjusted for cluster effect. The study revealed the prevalence of head-lice infestation was 50% among females and only 3% among males. Age stratification showed a high prevalence among females aged <20 years, and among 50% of female school-children. The prevalence was persistent among those with a history of infestation. The major risk factors were residing in a setting with other infected cases, and sharing a hair comb. The study also confirmed that ivermectin was safe and effective for field-based practice. It was considered a preferable treatment option. In conclusion, behavior-change communication should be implemented to reduce the observed high prevalence of head-lice infestation. Ivermectin may be an alternative choice for head-lice treatment, especially in remote areas.

Diversity, Interspecific Interaction and Abundance of Undergrowth in Monocultures and Integrated Systems of Natural Rubber Plantation in Danzhou, Southern China

  • Chima, Uzoma Darlington;Qi, Dongling;Wu, Zhixiang;Lan, Guoyu;Chen, Li
    • Journal of Forest and Environmental Science
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    • 제38권2호
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    • pp.75-89
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    • 2022
  • The negative impact of monoculture rubber plantations on biodiversity and associated ecological processes/ecosystem services has led to suggestions on the use of integrated land use systems for rubber cultivation and production in order to ensure environmental sustainability. However, there is paucity of information on the effect of such integrated land use systems on the diversity and abundance of the rubber plantation undergrowth. We evaluated and compared undergrowth plant species composition, richness, abundance, diversity and interaction, in three integrated systems (Rubber-Strelitzia reginae Integrated System - RSrIS, Rubber-Podocarpus nagi Integrated System - RPnIS & Naturally Managed Rubber Plantation - NMRP) with three Rubber Monoculture Plantations (RMP1, RMP2 & RMP3) adjacent to the integrated systems, respectively, at the Investigation and Experiment Station of Tropical Crops, Danzhou, Hainan, China. Undergrowth species density was higher in the rubber monocultures than in the integrated systems except in RSrIS. Species richness and diversity were also higher in the monocultures except in NMRP. Species similarity/interaction between the monocultures and the integrated systems was highest between RMP3 and NMRP. The NRMP proved to be the best model of natural rubber integrated system for the conservation of undergrowth species richness, diversity and interspecific interaction. However, the conservation of undergrowth species in other forms of integrated natural systems can be enhanced by considering the ecology of species to be integrated in terms of their growth characteristics, competitive nature, and ability to grow in association with other species.

Intestinal parasitic infections among children aged 12-59 months in Nyamasheke District, Rwanda

  • Evariste Hakizimana;Ju Yeong Kim;Singeun Oh;Moonsoo Yoon;Tai-Soon Yong
    • Parasites, Hosts and Diseases
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    • 제61권3호
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    • pp.304-309
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    • 2023
  • Intestinal parasitic infections are a public health burden and a major cause of illness in developing countries. The diseases lead to various health threats, including growth retardation and mental health-related disorders, especially in children. We assessed the risk factors for intestinal parasitic infections among children aged 12-59 months residing in Nyamasheke District, Rwanda. A cross-sectional descriptive study was conducted using secondary data from 1,048 children aged 12-59 months whose stool samples were examined for the presence of intestinal parasites and whose results were registered in the laboratory information system in 2020. The prevalence of intestinal parasites in children aged 12-59 months was 53.2%. The dominant parasites were Ascaris lumbricoides (13.1%), followed by Giardia lamblia (10.9%), Entamoeba histolytica (7.9%), Trichuris trichiura (6.5%), hookworms (1.7%), and Taenia species (1.4%). A significant association was observed between intestinal parasites and the literacy of mothers or children's caregivers (odds ratio (OR)=5.09, P<0.001). Children from farming households were 2.8-fold more likely to contract intestinal parasitic infections than those from nonfarming households (OR=2.8, P<0.001). A significant association was also observed between intestinal parasites and food safety (OR=4.9, P<0.001). Intestinal parasitic infections were significantly associated with hand hygiene practices after using the toilet and washing fresh fruits before eating (P<0.001). The information gathered will help public health providers and partners develop control plans in highly endemic areas in Rwanda.

Genetic factors influencing milk and fat yields in tropically adapted dairy cattle: insights from quantitative trait loci analysis and gene associations

  • Thawee Laodim;Skorn Koonawootrittriron;Mauricio A. Elzo;Thanathip Suwanasopee;Danai Jattawa;Mattaneeya Sarakul
    • Animal Bioscience
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    • 제37권4호
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    • pp.576-590
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    • 2024
  • Objective: The objective of this study was to identify genes associated with 305-day milk yield (MY) and fat yield (FY) that also influence the adaptability of the Thai multibreed dairy cattle population to tropical conditions. Methods: A total of 75,776 imputed and actual single nucleotide polymorphisms (SNPs) from 2,661 animals were used to identify genomic regions associated with MY and FY using the single-step genomic best linear unbiased predictions. Fixed effects included herd-year-season, breed regression, heterosis regression and calving age regression effects. Random effects were animal additive genetic and residual. Individual SNPs with a p-value smaller than 0.05 were selected for gene mapping, function analysis, and quantitative trait loci (QTL) annotation analysis. Results: A substantial number of QTLs associated with MY (9,334) and FY (8,977) were identified by integrating SNP genotypes and QTL annotations. Notably, we discovered 17 annotated QTLs within the health and exterior QTL classes, corresponding to nine unique genes. Among these genes, Rho GTPase activating protein 15 (ARHGAP15) and catenin alpha 2 (CTNNA2) have previously been linked to physiological traits associated with tropical adaptation in various cattle breeds. Interestingly, these two genes also showed signs of positive selection, indicating their potential role in conferring tolerance to trypanosomiasis, a prevalent tropical disease. Conclusion: Our findings provide valuable insights into the genetic basis of MY and FY in the Thai multibreed dairy cattle population, shedding light on the underlying mechanisms of tropical adaptation. The identified genes represent promising targets for future breeding strategies aimed at improving milk and fat production while ensuring resilience to tropical challenges. This study significantly contributes to our understanding of the genetic factors influencing milk production and adaptability in dairy cattle, facilitating the development of sustainable genetic selection strategies and breeding programs in tropical environments.

Malaria Diagnosis: A Brief Review

  • Tangpukdee, Noppadon;Duangdee, Chatnapa;Wilairatana, Polrat;Krudsood, Srivicha
    • Parasites, Hosts and Diseases
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    • 제47권2호
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    • pp.93-102
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    • 2009
  • Malaria is a major cause of death in tropical and sub-tropical countries, killing each year over 1 million people globally; 90% of fatalities occur in African children. Although effective ways to manage malaria now exist, the number of malaria cases is still increasing, due to several factors. In this emergency situation, prompt and effective diagnostic methods are essential for the management and control of malaria. Traditional methods for diagnosing malaria remain problematic; therefore, new technologies have been developed and introduced to overcome the limitations. This review details the currently available diagnostic methods for malaria.

열대곡선 헤아리기 (Enumerate tropical algebraic curves)

  • 김영록;신용수
    • 한국수학사학회지
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    • 제30권3호
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    • pp.185-199
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    • 2017
  • In tropical geometry, the sum of two numbers is defined as the minimum, and the multiplication as the sum. As a way to build tropical plane curves, we could use Newton polygons or amoebas. We study one method to convert the representation of an algebraic variety from an image of a rational map to the zero set of some multivariate polynomials. Mikhalkin proved that complex curves can be replaced by tropical curves, and induced a combination formula which counts the number of tropical curves in complex projective plane. In this paper, we present close examinations of this particular combination formula.

ON WELL-POSEDNESS AND BLOW-UP CRITERION FOR THE 2D TROPICAL CLIMATE MODEL

  • Zhou, Mulan
    • 대한수학회보
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    • 제57권4호
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    • pp.891-907
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    • 2020
  • In this paper, we consider the Cauchy problem to the tropical climate model. We establish the global regularity for the 2D tropical climate model with generalized nonlocal dissipation of the barotropic mode and obtain a multi-logarithmical vorticity blow-up criterion for the 2D tropical climate model without any dissipation of the barotropic mode.