• Korean Journal of Environmental Agriculture
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• v.18 no.4
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• pp.304-309
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• 1999

Biomass, tissue (foliage, stem. and root) nutrient concentration, and nutrient use efficiency (NUE) were determined for 1-year-old Pinus densiflora, Larix leptolepis and Betula platyphvlla var. japonica seedlings in a greenhouse under nitrogen (N) and phosphorus (P) fertilization treatments. There were no consistent patterns in the effect of fertilization on seedling growth, however, in most cases the addition of N and P had no stimulating effect on biomass. In general, seedling tissue N and P concentrations increased after fertilization. It appeared that fertilization induced luxury nutrient consumption because uptake was increased without altering biomass. The NUE. calculated as the ratio between total above and belowground production and nutrient content in seedlings, decreased with increasing N and P supply for P. densiflora and B. platyphylla var. japonica while that for L. leptolepisthe did not change. B. platyphylla var. japonica had the highest NUE, L. leptolepis the lowest, with P. densiflora having the intermediate NUE.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.5
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• pp.773-788
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• 2003

Ostrich farming is a developing industry in most countries in the world, with farm profitability being largely dependent on the quality of the products, especially skins and meat. To produce quality products, it is essential to ensure that nutrient supply matches the nutrient requirements of ostriches during their growth. To achieve this, information on feed utilisation efficiency and nutrient requirements of ostriches at different maturity stages is required. In South Africa, a number of experiments were carried out to assess the nutritive value of feed and to define the nutrient requirement of ostriches. These data were derived from limited number of birds and the direct application of the results to ostrich farming in Australia and other countries is questionable due to the difference in environment and feed resources. Initially ostrich farmers used data from poultry as a guideline for feed formulation, but in recent years more data has become available for ostriches. Ostriches have a better feed utilisation efficiency and a larger capacity of using high fibre feeds such as pastures than poultry. This review revealed that there are a number of areas there further nutritional research and development is required to ensure the ostriches are provided suitable diets to maximise farm profitability. These include the assessment of the nutritive value of feed ingredients for ostrich chicks and adult birds, the determination of nutrient requirements of ostriches under different farming systems, the development of ostrich diet for producing specific product, and grazing management strategies of ostriches in a crop-pasture rotation system.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.423-428
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• 2013

Although closed soilless culture is useful for saving water and fertilizers with minimizing environmental pollution, adequate management of nutrient solutions is still not stabilized in greenhouse cultivation. In order to investigate the problems occurred in closed soilless culture of Paprika (Capsicum annuum L., cv. Fiesta), we compared ion balance, fruit yield, and the water and fertilizer use efficiencies in the closed system with those in the open system. The plants were grown in rockwool culture with a nutrient solution of EC $2.5dS{\cdot}m^{-1}$. After 4 weeks of treatment, individual ratio of $NO{_3}^-$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ to total ion concentrations ($meq{\cdot}L^{-1}$) decreased from the initial value, especially the biggest decrement was observed in $K^+$, and on the other hand, $SO{_4}^{2-}$, $Cl^-$, and $Na^+$ were accumulated in the closed system. Yields after four-time harvests were 19% higher in the open system than in the closed system. Total volume of water used per unit area ($m^2$) in the open system was 20% higher, but the total water use per fruit was not significantly different between the two systems, while t total fertilizer use per fruit was 78% higher in the closed system. Amount of marketable fruits was not significantly different between the two systems. We concluded that the increase in $K^+$ supply and the replenishment of recycled nutrient solution every four weeks were required for preventing the imbalance or depletion of nutrients in the close soilless culture of paprika plants to get more balanced nutrient composition during whole cultivation period.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.27-33
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• 2001

The Ovarian developmental phases of the reproductive cycle of Rapana venosa can be classified into five successive stages by histological study: early active stage (September to February), late active stage (December to April), ripe stage (March to July), partially spawned stage (May to August), and recovery stage (June to September). To understand the characteristics of nutrient storage and utilization in the digestive gland cells with ovarian developmental phases, we examined the digestive gland - which is the major nutrient supply organ associated with ovarian development of the female purple shell - by biochemical methods. Total protein contents in the digestive gland tissues increased in March (late active stage) and reached the maximum in May (ripe and partially spawned stages), and then their levels sharply decreased in July (partially spawned and recovery stages). Total lipid contents in the digestive gland tissues reached the maximum in January (early active stage). Thereafter, their levels rapidly decreased from May (ripe and partially spawned stages) and reached a minimum in July (partially spawned and recovery stages). The total DNA contents did not significantly change regardless of the different developmental stages of the ovary. However, it was also found from biochemical analysis that changes in total RNA content follow the same seasonal cycling to protein. These results indicate that the digestive gland is an important energy storage and supply organ in purple shells, and that the nutrient contents of the digestive gland change in response to gonadal energy needs.

• Journal of Bio-Environment Control
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• v.13 no.3
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• pp.125-129
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• 2004

This study was conducted to identify the growth characteristics of melon cultivated with mixture medium of scoria and perlite in capillary system. The growth and fruit characteristics of all cultivars cultivated under the nutrient solution capillary supplying system were comprehensively favorable. Fresh fruit weight of the three cultivars was similar to weight criterion (1.8 - 2.0 kg/fruit) of melon. In melon of non-net type ‘Aris’ there were no differences in fruit characteristics between nutrient solution supply methods, but total soluble solid (TSS) was higher in drip and capillary systems showing $15.6^{\circ}$Brix and 15.5$^{\circ}$Brix, respectively, than that of mist spray system showing $14.4^{\circ}$Brix. In melon of net type, ‘Earl's elite’, drip and capillary systems showed better fruit characteristics and higher values of TSS compared to mist spray system. The change in pH in the medium before and after melon cropping was not significant between systems, but the pH of upper layer within medium in all system was higher than that of lower layer. The mineral content within lower layer showed higher value than that of the upper layer in drip system, but reversed in capillary system.

• Archives of Reconstructive Microsurgery
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• v.7 no.1
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• pp.54-61
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• 1998

Free vascularized fibular is the most usuful bony donor of the long bone reconstruction in reconstructive microsurgical field. It has many benifits such as very strong strut tubular bone, very reliable vascular anatomy with large vascular diameter with long pedicle, minimal donor site morbity too. In that situations of the huge long bone defects in distal femur or proximal tibia, the defective bony shape and strength of the transplanted fibular bone is not enough if only one strut of the fibula is transfered. The bony circulation of the fibula has two ways, one from nutrient artery via peroneal artery through nutrient foramen which makes endosteal arterial network inside of the fibula, another way is periosteal network through outside encircling vascular network of the bone which distributed in muscle sleeves of the fibular diaphysis. Authors modified free vascularized fibular bone graft with transverse osteotomy is made from the anterolateral aspect of the fibular shaft just distal to entry of the nutrient artery. This produces two vascularized bone struts that may be folded pararell to each other but that remain connected by the periosteum and muscle cuff surrounding the peroneal artery and veins. The proximal strut is vascularized by both a periosteal and endosteal blood supply, whereas the distal strut is vascularized by a periosteal blood supply alone. This procedure can call "doule barrel" free vascularized fibular graft. We performed 7 cases of doule barrel fashined fibular transplantation on distal femur and proximal tibial large defects. Average bone union time takes 7 months from that procedure. There were no significant bone union time differences between both proximal and distal struts. After solid union of the transfered double barrel fibular graft, there were no stress fracture in our series. We can propose double barrel free vascualized fibular graft is usuful method in that cases with very large bone defect on large long bones especially metaphyseal defects.

• Smart Media Journal
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• v.13 no.2
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• pp.16-22
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• 2024

Greenhouse provides opportunities to have big yield effectively and efficiently. However, many resources are required, such as fertigation, a kind of solution of nutrient. Resources supply is essential to cultivate crops. Inadequate supply will hinder plant growth whereas the surplus results in waste. In this paper, we are especially interested in the fertigation supply. Further, excess fertigation leads to drainage which is difficult to purify and threatens the environment. To address this challenge, we aim to predict the desired amount of fertigation. To achieve this objective, we first establish a prototype to record the climate conditions inside a rose greenhouse using Internet of Things sensors. Simultaneously, the desired fertigation amount is obtained with the help of weight scale and historical data of fertigation supply and drainage. Second, a method is proposed to predict the desired fertigation by taking the sensors' data as input, with a time-series model. Extensive experimental results suggest the potential of our objective and method. To be specific, our method achieves an average MAE 0.032 in the validation datasets.

• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.84-90
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• 2006

This study was conducted to anticipate nitrate reduction state in tree through measurement of nitrate reductase activity (NRA) and investigate the effect of nitrogen concentrations (100, 200, 400, and 600 $mg\;L^{-1}$) on growth, the nitrogen content of various tissue, and NRA of pear (Pyrus pyrifolia cv. Niitaka) seedlings in sand culture. Nutrient solutions used in this experiment were adjusted to pH 6.5 and fixed the ratio of ammonium and nitrate to 1:3 and trickle-irrigated 3 times a day. Tree height and dry weight of various organs in seedlings were higher in low nitrogen concentration (100 and 200 $mg\;L^{-1}$) than in high nitrogen concentration (400 and 600 $mg\;L^{-1}$). The shoot growth in 600 $mg\;L^{-1}$ was extremely poor by nitrogen over supply. Increasing the nitrogen concentration, the concentration of nitrate-N in leaves and roots were insignificantly changed but that of stems increased. The accumulation of total and reduced nitrogen in all organs with increasing concentrations of nitrogen supply were increased at 30 days after treatment but those of all organs at 60 and 90 days after treatment were highest in 600 $mg\;L^{-1}$, whereas there were no significant changes among other nitrogen concentration. The in vivo (${+NO_3}^-$) NRA of all organs did not relate to nitrogen concentration but the in vivo (${-NO_3}^-$) NRA of leaves except roots increased with increasing the nitrogen concentration. Therefore, the proper nitrogen concentration to promote growth and nitrate reduction of pear tree was 200 $mg\;L^{-1}$.

• Ocean and Polar Research
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• v.35 no.2
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• pp.157-170
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• 2013

We investigated the seasonal succession of phytoplankton assemblages in the eastern part of the South Sea of Korea in relation to surface water masses. The study areas are under the direct influence of the Tsushima Warm Current (TCW) throughout the whole year, with its strength known to be seasonally variable. The region is also influenced by coastal waters (CW) driven from the South Sea of Korea and East China Sea, particularly in summer, as indicated by low salinity in the surface water. Nutrient property of the TCW can reveals whether the origin of the TCW is the nutrient-rich Kuroshio Current or the oligotropic Taiwan Warm Current. Surface chlorophyll-a (Chl-a) concentrations displayed a large seasonal variation for all stations, with high values found in spring and autumn and low values in summer and winter. At station M (offshore) and P (intermediate location between M and R), Chl-a concentrations in October were higher than those in March, when spring bloom normally occurs. This may be related to deeper mixed layer depths in October. Diatoms dominated under conditions of high nutrient supply in which Chaetoceros spp. and Skeletonema costatum-like spp. were abundant. S. costatum-like spp. dominated at stations R (onshore station) and P in December when there was greater nutrient supply, especially of phosphate. Flagellates and dinoflagellates dominated at all three stations after diatoms blooms. Dominant species were Scrippsiella trochoid in April and Ceratium furca in October at station R, and Gyrodinium spp. and Gymnodinium spp. at station M during summer, when the effect of the oligotropic Taiwan Warm Current and the oligotropic coastal water from East China Sea were strong. Redundancy analysis showed clear seasonal successions in the phytoplankton community and environmental conditions, in which both principal components 1 and 2 accounted for 69.6% of total variance. Our results suggested that environmental conditions seemed to be determined by the origin of the TCW and the relative seasonal strength of the water masses of the TCW and CW, which may affect phytoplankton growth and compositions in the study area.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.812-818
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• 2014

Raising seedlings is important for fruit crops and is especially significant for strawberries as it accounts for 80% of their cultivation. However, there are few studies on raising seedlings of strawberries by hydroponics. Since strawberries show clear differences in growth characteristics based on cultivar, it is necessary to develop suitable fertilizer formula, concentration and pH for each cultivar, and also to examine the amount of nutrient feeding appropriate for each medium type. A key to raising seedlings of strawberries by hydroponics is the development of strategies to manage the concentration of nutrient solution. The mother plants of 'Daewang' strawberries were planted on hydroponics benches filled with cocopeat on March 28, 2012. Three nutrient solution treatments were employed during the term of raising seedlings: a type that supplied EC $0.6dS{\cdot}m^{-1}$ nutrient solution for 30 days and only water for 20 days [0.6 (30) + 20]; a type that supplied EC $1.2dS{\cdot}m^{-1}$ nutrient solution for 30 days and only water for 20 days [1.2 (30) + 20]; and a type that supplied EC $1.2dS{\cdot}m^{-1}$ nutrient solution for 50 days [1.2 (50)]. The plants were then planted on hydroponics benches filled with cocopeat on September 20, and managed with EC $0.6-0.8dS{\cdot}m^{-1}$ strawberry nutrient solution developed by Yamazaki. After planting, shoot growth, flowering rate and fruit quality of the first cluster were investigated. The petiole length, leaf length, leaf width and crown diameter showed the highest grown in the [1.2 (50)] treatment, followed by [1.2 (30) + 20], and then [0.6 (30) + 20], indicating that the higher concentration of nutrient solution was preferable for raising seedlings. However, the growth differences among treatments gradually disappeared as growth continued, and the crown diameter especially grew to exhibit almost no difference at all among treatments. The point of flowering came first in [0.6 (30) + 20], followed by [1.2 (30) + 20] and then [1.2 (50)]. The [0.6 (30) + 20] treatment showed much earlier flowering than other treatments, which implies that low-concentration nutrient solution may be beneficial to the flowering of 'Daewang' strawberries while raising seedlings. There was no statistically significant difference among treatments in fruit length, fruit diameter and fruit firmness. Fruit weight in [1.2 (50)] treatment was significantly higher than other treatments. However, soluble solids of fruit was the lowest in [1.2 (50)] treatment. Together, the results of this experiment imply that it is better to supply EC $0.6dS{\cdot}m^{-1}$ solution for 30 days and then supply only water for 20 days to adequately manage concentration of nutrient solutions during the period of raising seedlings of strawberries by hydroponics.