• Asian-Australasian Journal of Animal Sciences
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• v.28 no.7
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• pp.943-950
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• 2015

Heat stress has adverse effects on fertility of dairy animals. Decline in fertility is linearly associated with an increase in combination of both temperature and humidity. The purpose of this study was to investigate the relationship between temperature humidity index (THI) and the pregnancy rate of Murrah buffaloes in a subtropical climate. The effects of genetic and non-genetic factors viz., sire, parity, period of calving and age group at first calving were found non-significant on pregnancy rate. The effect of THI was found significant (p<0.001) on pregnancy rate of Murrah buffaloes calved for first time and overall pregnancy rate. The threshold THI affecting the pregnancy rate was identified as THI 75. The months from October to March showed THI<75 and considered as non heat stress zone (NHSZ), while months from April to September were determined as heat stress zone (HSZ) with $THI{\geq}75$. The lowest overall pregnancy rate (0.25) was obtained in July with THI 80.9, while the highest overall pregnancy rate (0.59) was found in November with THI 66.1. May and June were identified as critical heat stress zone (CHSZ) within the HSZ with maximum decline (-7%) in pregnancy rate with per unit increase in THI. The highest overall pregnancy rate was estimated as 0.45 in NHSZ with THI value 56.7 to 73.2. The pregnancy rate was found to have declined to 0.28 in HSZ with THI 73.5 to 83.7. However, the lowest pregnancy rate was estimated as 0.27 in CHSZ with THI value 80.3 to 81.6.

• Journal of Environmental Science International
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• v.29 no.7
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• pp.785-788
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• 2020

We investigated the oviposition characteristics of Protaetia brevitarsis seulensis, focusing on zone breeding throughout the year in terms of the development and utilization of insect resources. To select Protaetia brevitarsis seulensis individuals laying a large number of eggs, the number of eggs laid for each individual was measured for each individual after emergence as adults from larvae grown at room temperature in five farmhouses. The five study zone included Gongju (Tancheon), Gyeonggi (Himsen), Chungnam (Gyeryong), Taean (Wonbuk), and Siheung (Baekse). The average oviposition tendency during a 12-week period obtained from the five regions was somewhat different; however, there was no remarkable difference in overall tendency. The maximum oviposition in Protaetia brevitarsisseulensis in the five regions occurred between 6 and 7 weeks. Compared toother regions, the average cumulative number of eggs laid during the 12-week period was higher (40%-60%) in Gongju (Tancheon) and Gyeonggi (Himsen). These results indicate that in two regions, zone breeding is selected as a system for increasing the demand for insects.

• Geomechanics and Engineering
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• v.38 no.3
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• pp.215-229
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• 2024

Because of the various patterns of deep-water inrush and complicated mechanisms, accurately predicting mine water inflows is always a difficult problem for coal mine geologists. In study presented in this paper, the water inrush channels were divided into four basic water diversion structures: aquifer, rock fracture zone, fracture zone and goaf. The fluid flow characteristics in each water-conducting structure were investigated by laboratory tests, and multistructure and multisystem coupling flow analysis models of different water-conducting structures were established to describe the entire water inrush process. Based on the research of the water inrush flow paths, the analysis model of different water inrush space structures was established and applied to the prediction of mine water inrush inflow. The results prove that the conduction sequence of different water-conducting structures and the changing rule of permeability caused by stress changes before and after the peak have important influences on the characteristics of mine water-gushing. Influenced by the differences in geological structure and combined with rock mass RQD and fault conductivity characteristics and other mine exploration data, the prediction of mine water inflow can be realized accurately. Taking the water transmitting path in the multistructure as the research object of water inrush, breaking through the limitation of traditional stratigraphic structure division, the prediction of water inflow and the estimation of potentially flooded area was realized, and water bursting intensity was predicted. It is of great significance in making reasonable emergency plans.

• Journal of Environmental Science International
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• v.29 no.9
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• pp.935-938
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• 2020

This study investigated the oviposition characteristics of Protaetia brevitarsis seulensis after emergence as adults from the larva collected from three regions in Gangwon-do, Chungcheongnam-do, and Jeju-do. The laying egg method was identified with zone breeding, and the average and cumulative number of eggs laid were measured once a week for seven weeks. The average number of eggs laid peaked until 4 weeks, and subsequently decreased. The source areas with respect to average number and cumulative number of eggs laid were in the order of Jeju > Chungnam > Gangwon. In conclusion, this result suggests a method for continuously improving management and economic feasibility of insect farming by securing genetic diversity, and raising the most productive breeds to select individuals form regions associated with high numbers of laid eggs.

• ALGAE
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• v.38 no.2
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• pp.141-150
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• 2023

Light quality is a common environmental factor which influences the metabolism of biochemical substances in algae and leads to the response of algal growth and development. Pyropia yezoensis is a kind of economic macroalgae that naturally grows in the intertidal zone where the light environment changes dramatically. In the present study, P. yezoensis thalli were treated under white light (control) and monochromatic lights with primary colors (blue, green, and red) for 14 days to explore their physiological response to light quality. During the first 3 days of treatment, P. yezoensis grew faster under blue light than other light qualities. In the next 11 days, it showed better adaptation to green light, with higher growth rate and photosynthetic capacity (reflected by a higher rETR_max = 61.58 and E_k = 237.78). A higher non-photochemical quenching was observed in the treatment of red light than others for 14 days. Furthermore, the response of P. yezoensis to light quality also results in the difference of photosynthetic pigment contents. The monochromatic light could reduce the synthesis of all pigments, but the reduction degree was different, which may relate to the spectral absorption characteristics of pigments. It was speculated that P. yezoensis adapted to a specific or changing light environments by regulating the synthesis of pigments to achieve the best use of light energy in photosynthesis and premium growth and metabolism.

• Journal of Korean Society of Forest Science
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• v.88 no.3
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• pp.379-388
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• 1999

As a first step for delineating the provenance regions of the forest trees in Korea, horizontal zones have been deduced primarily from the various climatic factors such as annual mean temperature, extremely low temperature, relative humidity, annual gum of possible growing days, duration of sunshine and dry index. The basic concept to the delineation of the provenance regions was based on the ecological regions, which was likely to be more practical than that on the basis of the typical provenance regions at the species level. Primary classification of the regions has been based on the forest zones(sub-tropical, warm-temperate, mid-temperate and cool-temperate) as a broad geographic region. Further classification has been carried out using cluster analyses among the basic regions within forest zone. On the basis of clustering, a total of 19 regions including 3 from sub-tropical, 6 from warm-temperate, 8 from mid-temperate and 2 from cool-temperate was horizontally delineated. Of the mean values of 6 climate factors at the broad geographic region level, three factors such as annual mean temperature, extremely low temperature, annual growing days showed directional tendencies from subtropical to cool-temperate, while the others didn't. The values of relative humidity, duration of sunshine and dry index varied among the provenance regions within forest zone. These three factors might he more sensitive by the micro-environment condition than by the macro-environment condition. Present study aimed to delineate the primary provenance regions for tentative application to forest practices. These will be stepwise revised through the supplement using accumulated information regard to genecological data.

• Korean Journal of Animal Reproduction
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• v.12 no.3
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• pp.148-155
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• 1988

Holstein cows being raised in the Kangweon district were examined on the breeding status and occurrence of reproductive disorder. The results obtained were as follows; 1. The cows above six years old in the alpine area were raised more than those in high level zone and plate zone. 2. A total of 1,350 Holstein cows were examined on the breeding status. They were 71.9% conceived cows, 7.9% of uncertain1$\frac{1}{2}$ regnancy, 7.0 of physiological vacancy and 13.3 of reproductive disorder. 3. The percentage of cows conceived by 1, 2, 3 and more than 4 times of A.I. was 49.9, 29.2, 13.3 and 7.6, respectively. 4. In the nutritional condition of infertile coes, excellent, good, fair and poor were 6.7, 30.2, 34.1 and 29.1, respectively. In the good and fair nutritional condition, the cows of ovarian syndrome were 15.6% of persistent corpus luteum, and 11.7% of follicular cystic ovary and lutein cystic ovary, respectively. 5. Among 179 inferTile cows, distributions of reproductive disorder were 43.0, 39.1, 3.9, 3.9 and 10.1% in ovary, uterus vagina, oviduct and others, respectively. Ovary showed higher percentage than any other reproductive organs. Among the ovarian syndromes, follicular cystic ovary, lutein cystic ovary and persistent corpus luteum were 28.6, 28.6 and 23.4%, respectively. 6. A cow group of six and seven-year old showed the highest percentage(21.0% and 23.3%) among the age groups in infertile cows. In the syndrome of reproductive disorder, catarrhal endometritis, latent endometritis, follicular cystic ovary and lutein cystic ovary were 14.5, 14.0, 12.3 and 12.3%, respectively. 7. Infertile cows with complex syndrome of genital disease was 31.8%.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.274-286
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• 2016

Carbon dioxide ($CO_2$) accounts for about 72% of the total greenhouse gas emissions. It is also widely known as a major cause of global warming. According to the IPCC's fifth evaluation report, the growth rate of atmospheric $CO_2$ has increased by 35% for the last 100 years and global warming is occurring much more rapidly than expected since 1990s. As a result of climate change, global warming is increasing the frequency and severity of extreme weather events around the world, which has changed forest vegetation zone and vegetation phenology. The Kyoto Protocol recognizes the importance of forests and refers to the conservation and enhancement of forests as sinks and reservoirs of greenhouse gases. In this regard, studies of tree responses to climate change are indispensable for predicting changes in the forest ecosystems in the future. Therefore, studies using long-term climate change research facilities, associated with long-term ecological research (LTER) in the fields, will make a considerable contribution to predict and approach the changes in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.207-213
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• 1999

Thirty-eight glutinous rice varieties were classified into nine groups on the scatter diagram by the upper two principal components (56% contribution to the total information) based on eleven physicochemical characteristics including the viscograms and physical properties of cooked rice. The first principal component was the factor mainly associated with the viscogram characteristics of rice flour emulsion and the second was the factor chiefly related to the physical properties of cooked rice and water absorbability of rice grain. Indica glutinous rices were clearly distinguished from japonica ones by the first principal component score. Javanica glutinous rices were widely distributed on the intermediate zone between indica and japonica or on several japonica rice groups. Significant positive or negative correlations were found among water absorption rates of rice grain, physical properties of cooked rice, and viscogram characteristics of rice flour. Especially in japonica glutinous rices, the breakdown and setback viscosities of rice flour were closely associated with the alkali digestion value of milled rice and the stickiness of cooked rice. The frequency ratio of short glucose chains (A-chain) to intermediate glucose chains (B-chain), the ratio of B- chains to long glucose chains (C-chain) and the relative frequency of A- or B-chain fractions representing the amylopection structure of rice starch was closely associated with the breakdown and setback viscosities of rice flour.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.4
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• pp.333-339
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• 1991

Eighty-two ewes of Balochi breed, two to four years of age were used in a completely randomized design to study the effect of winter supplementation on their performance in Kalat area of Balochistan and randomly divided into two groups of 40 and 42 animals. Two treatments (T1 and T2) studied were : 250 gm/animal/day of a 50 : 50 mixture of cottonseed cake and barley grain fed from Oct. 20 to Dec. 18, 1988 plus grazing and 500 gm/animal/day of the same feed mixture fed from Oct. 9 to Dec. 18, 1988 in addition to grazing. Lucerne hay and wheat straw in a 50 : 50 ratio were provided to all the ewes for a period of one month from Jan. 6, 1989 @ 320 gm/animal/day to sustain them in severe winter. Same feeding levels to the same ewe groups were again fed from Mar. 1 to May 27, 1989. Three breeding rams stayed with the flock from Nov. 1 to Dec. 13, 1988. Lambing took place from Apr. 2 to May 12, 1989. Conception, lambing and mortality percentage was found different (P<.05) between T1 and T2 (12.5 vs 14.8 kg). The ewes on T2 maintained higher body weights throughout winter than the ewes on T1. The results are suggestive of improvement in conception rate with winter supplementation (flushing) and decrease in ewe mortality. Late-gestation and early-lactation supplemental feeding of ewes results in increases in weaning weights of their lambs.