• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.47-51
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• 1982

Red tilapia fingerlings were tested for 45 days on the growth rate in a closed recirculating water system omitting filter bed and was compared with common carp fingerlings grown together in the same tank and also with red tilapia fingerlings grown in a well conditioned conventional pond. The tank water was kept in deepgreen colour by heavy phytoplankton bloom during the most of the experimental period and duckweeds, Lemna sp. and water hyacinth, Eichhornia crassipes were put to grow in the parts of the water system. Total ammonia level in the tank was mostly kept at about 5 to 7 ppm, with a fluctuation between 3.4 and 11.2 ppm. Average daily growth rate of the tilapia in the experimental tank was $6.5112\%$ without any mortality, compared to $3.617\%$ for common carp fingerlings involving some mortality in the same tank, and to $5.7712\%$ for the tilapia grown in the conventional pond. The feed used for the experiment was one prepared for the rearing of common carp, and the duckweed grown in parts of the water system was routinely collected and fed to the tilapia in the tank as supplementary diet probably satisfying unknown growth factors.

• The Journal of Korean Medical History
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• v.33 no.1
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• pp.31-41
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• 2020

Purpose : This study compares prescriptions in the 1901 edition of the Donguisusebowon (東醫壽世保元) and the 1901 edition of 24 Revised Tae-eum constitution prescriptions (新定太陰人病應用要藥二十四方) (1901PCDT) with medical herbs found in classical texts. This study also examines whether to include patterns which compose medical herbs for the person of Tae-eum constitution (太陰人). Method : The prescriptions for Tae-eum-in in the Shinchukbon and the ingredients of medical herbs of the prescriptions of the Complete Works of Zhang Jingyue (景岳全書), Secret Works of Universal Benefit (廣濟秘笈), Treasured Mirror of Eastern Medicine (東醫寶鑑), Comprised Edition for Formulas (方藥合編), Protecting Essence for Longevity (壽世保元), Introduction to Medicine (醫學入門), New Book for Saving People (濟衆新編 ENGLISH), and Compendium of Local Medicinals and Formulas (鄕藥集成方) were input into a database. The prescriptions were examined and combinations of medical herbs used to treat the person of Tae-eum constitution were noted. Result : Among the prescriptions for the person of Tae-eum constitution, similar examples of the 17 prescriptions of Kudzu Decoction to Relieve the Muscles (葛根解肌湯), Regulate the Stomach and Coordinate the Purity Decoction (調胃升淸湯), Clear the Heart and Lotus Pip Decoction (淸心蓮子湯), Decoction for Stabilizing Asthma with Ephedra (麻黃定喘湯), Profuse Heat and Sparse Cold Decoction (熱多寒少湯), Decoction for Coordinating Qi with Kudzu (葛根承氣湯), Major Decoction for Coordinating Qi with Kudzu (葛根大承氣湯), Minor Decoction for Coordinating Qi with Kudzu (葛根小承氣湯), Decoction for Dispersing the Exterior with Ephedra (麻黃發表湯), Boost the Lung Essence Decoction (補肺元湯), Major Supplementing Decoction with Deer Antler Velvet (鹿茸大補湯), Boosting Black Essence Pill (拱辰黑元丹), Honeylocust Fruit and Rhubarb Decoction (皂角大黃湯), Kudza and Duckweed Decoction (葛根浮萍湯), Sweet Flag and Polygala Powder (石菖蒲遠志散), Liriopis and Polygala Decoction Powder (麥門冬遠志散), and Cattle Gallstone Formula to Clear the Heart (牛黃淸心元) were found in important ancient literature and Dried Chestnut and Holotrichia Decoction (乾栗蠐螬湯) and Dried Chestnut and Tree of Heaven Root Bark Decoction (乾栗樗根皮湯) are the combination originally set by Lee Jema. Conclusion : Because 70.8% of the prescriptions in 1901PCDT could be found in literature which were pervasive in the period of the Joseon Dynasty (the period of Ming and Qing), it corresponds with Lee Jema's view that medical men in the Song, Yuan, and Ming Dynasties disclosed half of the prescriptions for Tae-eum person by studying these texts more.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.2
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• pp.280-289
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• 2015

Anaerobic digestion is an efficient and renewable energy technology that can produce biogas from a variety of biomasses such as animal manure, food waste and plant residues. In developing countries this technology is widely used for the production of biogas using local biomasses, but there is little information about the value of these biomasses for energy production. This study was therefore carried out with the objective of estimating the biogas production potential of typical Vietnamese biomasses such as animal manure, slaughterhouse waste and plant residues, and developing a model that relates methane ($CH_4$) production to the chemical characteristics of the biomass. The biochemical methane potential (BMP) and biomass characteristics were measured. Results showed that piglet manure produced the highest $CH_4$ yield of 443 normal litter (NL) $CH_4kg^{-1}$ volatile solids (VS) compared to 222 from cows, 177 from sows, 172 from rabbits, 169 from goats and 153 from buffaloes. Methane production from duckweed (Spirodela polyrrhiza) was higher than from lawn grass and water spinach at 340, 220, and 110.6 NL $CH_4kg^{-1}$ VS, respectively. The BMP experiment also demonstrated that the $CH_4$ production was inhibited with chicken manure, slaughterhouse waste, cassava residue and shoe-making waste. Statistical analysis showed that lipid and lignin are the most significant predictors of BMP. The model was developed from knowledge that the BMP was related to biomass content of lipid, lignin and protein from manure and plant residues as a percentage of VS with coefficient of determination (R-square) at 0.95.This model was applied to calculate the $CH_4$ yield for a household with 17 fattening pigs in the highlands and lowlands of northern Vietnam.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.271-278
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• 2021

Azolla is a genus of small aquatic ferns native to Asia, Africa, and America. Azolla is potentially significant as a nitrogen source in agriculture, particularly in conjunction with rice (Oryza sativa L.) cultivation. In addition, Azolla may either control weeds or act as a weed depending on management; therefore, we aimed to determine the effect of Azolla incorporation on weed (e.g., Monochoria vaginalis, Rotala indica, Aeschynomene indica, and Cyperus amuricus) control and its other benefits during rice cultivation. The effects of Azolla on weed emergence were evaluated based on plot area coverage by the Azolla mat, which appears as a green sheet over water, and the rate of weed emergence in paddy field. Weed occurrence was investigated 40 days after Azolla inoculation. Soil samples from the experimental plots were collected following harvest in 2014-2015, and analyzed. Moreover, rice growth, yield, and grain quality were measured. Azolla suppressed weed growth by 72%. Azolla mat incorporation in rice fields suppressed weed growth by over 60%. In addition, Azolla promoted nitrogen fixation. Compared with nitrogen management using chemical fertilizers, Azolla incorporation showed the potential for various positive effects, including the improvement of soil fertility by increasing total nitrogen, and organic matter content. Rice grown with Azolla maintained its yield without additional herbicide treatment. Moreover, the palatability of cooked rice was better when grown with Azolla.

• Korean Journal of Environment and Ecology
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• v.31 no.4
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• pp.349-364
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• 2017

Duckweed family (Lemnaceae Martinov), including the genus Lemna L., is a typical floating aquatic perennial plant, and about five genera and 40 species in the family are in wide distribution around the world except the polar regions. The genus Lemna is the smallest and the simplest plant among the angiosperms. It has a characteristic of doubling every three days with fast vegetative propagation, which helps the organisms to increase in rapid growth. As such, the plant is ideal for environmental pollution assessment and toxicity test. Although taxonomists and scholars have used different scientific names for the species, many of them have agreed that there is only one member of species of the genus Lemna in Korea. Paying attention to the external morphological variation observed in the Korean genus Lemna, we conducted a molecular phylogenetic analysis to identify the entity of the Korean Lemna species and to investigate the possibility of two or more members of the species existing in Korea. We determined and aligned the DNA sequences of the atpF-H region of the chloroplast DNA in 37 populations of the nationally distributed Lemna species. The results showed that the sequence length of the cp DNA atpF-H region was 463-483 bp, the length of the aligned sequences was 488 bp, and the number of variation site in nucleotide sequences was 47. There were two types of aligned sequences of the cp DNA atpF-H region from 37 populations of Lemna species in Korea. The maximum parsimony analysis revealed that the Korean Lemna consists of two clades, and one of them had two subclades. The results suggest that, contrary to the general understanding, at least two taxa (L.aequinoctialis, L.minor) exist in Korea.

• The Korean Journal of Pesticide Science
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• v.8 no.4
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• pp.338-346
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• 2004

The methanol extract of Chloranthus japonicus roots effectively controlled the development of rice blast(Magnaporthe grisea), rice sheath blight(Corticium sasaki), tomato pay mold(Btrytis cinerea), tomato late blight(Phytophthora infestans), and wheat leaf rust(Puccinia recondita). From the methanol extract of C. japonicus roots, three antifungal substances were isolated. Their chemical structures were determined to be shizukanols B, C, and D mainly by mass and NMR spectral data. Among the three substances, shizukanol C showed the strongest inhibitory activity against mycelial growth of the plant pathogenic fungi tested; it completely inhibited mycelial growth of M. grisea. Colletotrichum gloeosporioides, and C. acutatum at concentrations of more than $12.5{\mu}g$/ and P. infestans at concentrations of more than $3.13{\mu}g/m\ell$. They also controlled effectively the development of rice blast and wheat leaf rust. On the other hand, they caused phytotoxic symptoms on barley leaves and inhibited the growth of duckweed (Lemna paucicostata) with $EC_{50}$ values of $30.0{\mu}g/m\ell$ for shizukanol B, $49.9{\mu}g/m\ell$ for shizukanol C, and $154{\mu}g/m\ell$ for shizukanol D. In addition, shizukanol C showed an insecticidal activity against brown planthopper (Nilaparavata lugens), peen peach aphid (Myzus persicae), diamond-back moth (Plutella xylostella), and tobacco cutworm (Spodoptera litura) of the 5 arthropod pests tested with mortality values of more than 60% at a concentration of $1,000{\mu}g/m\ell$.