• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.445-448
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• 2009

This study examined the effect of the uptake of one and two electrons on the atomic structure of three isomers of $C_{20}$ clusters, namely the ring, bowl (corannulene like), and cage (the smallest fullerene). Geometry optimizations were performed using the hybrid density functional (B3LYP) methods for neutral, singly and doubly charged $C_{20},\;{C_{20}}^-,and\;{C_{20}}^{2-}$. These results show that the symmetry of the lowest energies for ring and bowl isomers were not changed, whereas the increasing order of energy for the cage (the smallest fullerene) isomers was changed from $D_{2h}\;<\;C_{2h}\;{\leq}\;C_2\;of\;C_{20}\;through\;Ci\;<\;C_{2h}\;<\;C_2\;<\;D_{2h}\;of\;{C_{20}}^-\;to\;Ci\;<\;C_2\;<\;D_{2h}\;<\;C_{2h}\;of\;{C_{20}}^{2-}$. The reduced symmetry isomers of the cage have comparative energy and the ground state symmetry of the neutral and single and double charged $C_{20}$ decreased with increasing number of electrons taken up in the point of energetics. Interestingly, the difference in energy between the ground state and the next higher energy state of ${C_{20}}^{2-}$ was 3.5kcal/mol, which is the largest energy gap of the neutral, single anion and double anion of the cage isomers examined.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.217-225
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• 1998

This study was performed to compare the effects of a fish cage on the structure of meiobenthic communities at two locations during May, 1996. The number of meiofaunal taxa at the existing cage site and control site was 15 and 26, respectively. Nematoda was the most dominant group of meiobenthos. Nematoda and Sarcomastigophora comprised more than $90\%$ of total meiofauna at both sites. The total density of control site was 7,702 inds./$10\;cm^{2}$ which is 10 times more than that of fish cage site. The density was highest in the upper 1 cm and decreased with sediment depth. The nematodes/harpacticoid copepods ratio as an index of pollution monitoring for benthic ecosystem at fish cage site was two times higher than at control site. Kinorhyncha known to be sensitive to pollution stress was not found at fish cage site.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1310-1319
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• 2005

This experiment was conducted to determine the effects of cage density (CD) and humate supplementation (HS) on laying performance, metabolic profile, and egg quality during the peak production period in hens. Lohman layers (n = 180, 46 wks of age) were blocked according to the location of cages and then allocated randomly to two levels of CD (4 or 6 hens per cage or 540 vs. 360 $cm^2$/hen) and three levels of HS (0, 0.15, and 0.30%). Egg production (EP) and feed consumption (FC) were measured daily; egg weight was measured bi-weekly; and BW was measured before and after the experiment. Blood and additional egg samples were obtained at the end of the experiment for determination of metabolic profile and egg quality. The data were analyzed using two-way ANOVA as repeated measures. Except for FC, CD did not affect laying performance parameters. Hens placed in high-density cages had lower FC than hens placed in normal-density cages. Increasing HS level linearly increased FC, EP, and feed conversion ratio (FCR). There was a CD by HS interaction effect on FC and EP. Hens placed in high-density cages had greater serum glucose, total protein, albumin, globulin, Ca, and P concentrations and tended to have greater serum corticosterone concentration than hens placed in normaldensity cages. Increasing HS level linearly increased serum glucose, total protein, albumin, globulin, creatine, and Ca concentrations and linearly decreased serum triglyceride and very low-density lipoprotein concentrations. There was a CD by HS interaction effect on serum glucose and albumin concentrations. There were no alterations in egg quality parameters in response to increasing CD. Albumen index and Haugh unit decreased linearly and other egg quality parameters did not change as HS level increased. In conclusion, increased caging density adversely affected metabolic profile, despite insignificantly deteriorating laying performance. Moreover, benefits from humate supplementation seem to be more noteworthy for hens housed in stressing conditions than for hens housed in standard conditions.

• The Korean Journal of Malacology
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• v.31 no.2
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• pp.93-101
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• 2015

The effects of different stocking densities on the growth and survival rate of the 3-year-old pacific abalone, Haliotis dicus hannai were investigated in marine net cage for a year. Stocking densities in net cage ($2.4{\times}1.2m$) was set 15, 30, 45 and 60 percentage (= per)/sq m (square meter, $m^2$) with share to cross-sectional area per shelter. The water temperature during the testing period was $8.2^{\circ}C-22.1^{\circ}C$, and salinity is $33.5{\pm}0.6psu$, and dissolved oxygen is $7.87{\pm}0.86mg/L$. In the shell length (initial size : $71.50{\pm}2.28mm$) growth and shell breadth (initial size : $46.43{\pm}2.28mm$) of the test abalones, the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rates (SGR) of the 15 per/sq m and 30 per/sq m were higher than those of 45 per/sq m and 60 per/sq m density group (P < 0.05). Also in the weight (initial weight : $35.7{\pm}8.1g$), it showed the same results. In survival rates, it were that 15 per/sq m and 30 per/sq m is significantly higher than 45 per/sq m and 60 per/sq m. Therefore, it was that the 15 per/sq m is optimized stocking density in marine net cages about the 3-year-old pacific abalone over 70 mm size. The result shown that total cross-sectional area under the shelter is based on 15 per/sq m ($2.4{\times}2.4m$, 354 number in a net cage) is suitable for fast growth and survival. But if the economy consider, optimized stocking density would be appropriate to accept 30 per/sq m ($2.4{\times}2.4m$, 710 number in a net cage).

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.381-386
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• 2010

We have cultured the bluefin tuna in Yokjido, Tongyeong with floating cage which was vulnerable to harmful dinoflagellate, Cochiodinium polykrikoides. This study inspected a vertical migration of phytoplankton and Chl-a for reasonable sinking depth in floating cage. Furthermore, we analyzed the fluctuation of the phytoplankton including harmful dinoflagellates occurring in Yokgido for 6 years. Total cell density showed a significant monthly variation and the flora was predominated with diatoms. Gymnodinium sp. occurred 19 times, the greatest number of occurrence in all kinds of dinoflagellates during summer. In particular, the total number of occurrence at C. polykrikoides was 8, and harmful dinoflagellates such as Karenia brevis/Fibrcapsa japonica occurred. The relationship between Chl-a concentration/total cell number and sunset/sunrise was significant and reasonable sinking depth in floating cage was found to be at least 3m from the water surface, which was associated with massive fish kills caused by C. polykrikoides.

• The Korean Journal of Malacology
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• v.30 no.3
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• pp.219-226
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• 2014

The effects of different stocking densities on the growth and survival rate of the abalone, Haliotis discus hannai, were investigated in marine net cage for two years. Stocking density was set 15, 30, 45 and 60 percentage $(=per.)/m^2$ with share to cross-sectional area per shelter. The primary rearing period (PRP) and the secondary rearing period (SRP) were conducted by a year. One year mean water temperature of PRP and SRS showed the difference about $2^{\circ}C$. In the growth (initial mean shell length of abalone : $36.14{\pm}2.28mm$) of PRP, the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rate (SGR) of the $15per./m^2$ were higher than those of density groups (P < 0.05). Survival rates of all density groups were showed no significant difference. In the growth (mean shell length of abalone : $55.26{\pm}6.93mm$) of SRP, ARG, DGR and SGR of stocking density groups showed no significant difference except for $45per./m^2$ density group. Survival rate in the low-density (15, $30per./m^2$) was more than 70%, and those of the high-density (45, $60per./m^2$) were less than 31% and 9%, respectively. These results showed that the appropriate stocking density for $15per./m^2$ was seven hundred fifty number per one net cage ($2.4{\times}2.4m$), during PRP using 3-4 cm abalone in length. Also for the secondary rearing period, the optimal stocking density (shell length 5-6 cm of abalone) consider with the economical efficiency was determined to be $30per./m^2$, resulting the productivity improved.

• Journal of Korean Neurosurgical Society
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• v.65 no.1
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• pp.96-106
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• 2022

Objective : The most common complication of anterior cervical discectomy and fusion (ACDF) is cage subsidence and maintenance of disc height affects postoperative clinical outcomes. We considered cage subsidence as an inappropriate indicator for evaluating preservation of disc height. Thus, this study aimed to consider patients with complications such as reduced total disc height compared to that before surgery and evaluate the relevance of several factors before ACDF. Methods : We retrospectively reviewed the medical records of 40 patients who underwent stand-alone single-level ACDF using a polyetheretherketone (PEEK) cage at our institution between January 2012 and December 2018. Our study population comprised 19 male and 21 female patients aged 24-70 years. The minimum follow-up period was 1 year. Twenty-seven patients had preoperative bone mineral density (BMD) data on dual-energy X-ray absorptiometry. Clinical parameters included sex, age, body mass index, smoking history, and prior medical history. Radiologic parameters included the C2-7 cobb angle, segmental angle, sagittal vertical axis, disc height, and total intervertebral height (TIH) at the preoperative and postoperative periods. Cage decrement was defined as the reduction in TIH at the 6-month follow-up compared to preoperative TIH. To evaluate the bone quality, Hounsfield unit (HU) value was calculated in the axial and sagittal images of conventional computed tomography. Results : Lumbar BMD values and cervical HU values were significantly correlated (r=0.733, p<0.001). We divided the patients into two groups based on cage decrement, and 47.5% of the total patients were regarded as cage decrement. There were statistically significant differences in the parameters of measuring the HU value of the vertebra and intraoperative distraction between the two groups. Using these identified factors, we performed a receiver operating characteristic (ROC) curve analysis. Based on the ROC curve, the cut-off point was 530 at the HU value of the upper cortical and cancellous vertebrae (p=0.014; area under the curve [AUC], 0.727; sensitivity, 94.7%; specificity, 42.9%) and 22.41 at intraoperative distraction (p=0.017; AUC, 0.722; sensitivity, 85.7%; specificity, 57.9%). Using this value, we converted these parameters into a bifurcated variable and assessed the multinomial regression analysis to evaluate the risk factors for cage decrement in ACDF. Intraoperative distraction and HU value of the upper vertebral body were independent factors of postoperative subsidence. Conclusion : Insufficient intraoperative distraction and low HU value showed a strong relationship with postoperative intervertebral height reduction following single stand-alone PEEK cage ACDF.

• Journal of Aquaculture
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• v.13 no.4
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• pp.339-351
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• 2000

Optimal environmental conditions, that sustained fastest growth, lowest mortality and abnormality of the scallop Patinopecten yessoensis, were identified from field experiments undertaken at Chumunjin during 1991-1998. Temperature within the water column 10~30 m depth ranged between 5 and 23$^{\circ}C$; high temperature and daily fluctuation resulted in growth retardation and heavy mortality of the scallop. Optimal salinity range was between 31.5 and 34.5%0 and water transparency 6.0 and 18.1 m, which was significantly affected by phytoplankton density. Chlorophyll concentration ranged between 0.04 and 3.51 f.lgfL. Low temperature and high chlorophyll concentration appear to support faster growth of the scallop. Optimal periods of transplantation for intermediate culture were between mid July and early November: cultured under high density during July-August as a first step and under low density during mid September through early November as a second step. Optimal stocking density in square net cage (<35${\times}$35 em) for intermediate culture was 30-40 individuals per cage for main culture using lantern net and 80 -100 individuals of the size of 1.5 ~ 3.0 em shell height per cage for sowing culture. During the intermediate culture, the highest growth was realized, when the cage was held at water depth between 10 and 15 m. Water depth below 25 m, however, was best to avoid mass mortality during the periods of abnormally high water temperature and high variation of water temperature. The daily growth rate during the intermediate culture was between 0.019~0.381 mm; low in January and February but high in March and April. It is suggested that the main culture is commenced before June under low stocking density to avoid the possibility of mass mortality during summer by high water temperature.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1752-1760
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• 2005

In this experiment, the effects of cage density (CD) and probiotic supplementation (PS) on laying performance, metabolic profile, and egg quality in peak-producing hens were evaluated. After blocking according to the cage location, Lohman layers (n = 180, 46 wks of age) were allocated randomly to two levels of CD (540 vs. 360 $cm^2$/hen) and three levels of PS (0, 0.15, and 0.30%). Probiotic contained Enterococcus faecium culture (10${\times}$10$^9$ cfu/g). Egg production (EP) and feed consumption (FC) were measured daily; egg weight (EW) was measured bi-weekly; BW was measured before and after the experiment; and blood samples were obtained at the end of the experiment. The data were analyzed using two-way ANOVA. Increasing CD decreased FC (125.0 vs. 120.8 g/d, p<0.0001) and FCR (1.93 vs. 1.87, p<0.0001) and did not alter EP, EW, and BW. Increasing level of PS linearly decreased FC (p<0.02) and FCR (p<0.006). Averages were 123.9, 123.2, and 121.6 g/d for FC and 1.91, 1.92, and 1.86 for FCR in hens supplemented with 0, 0.15, and 0.30% probiotic, respectively. Hens placed in high-density cages had greater serum corticosterone concentration than hens placed in normal-density cages (12.8 vs. 11.3 $\mu$g/dL, p<0.04); CD did not affect concentrations of other metabolites. Increasing level of PS linearly increased serum glucose, albumin, and creatine concentrations and quadratically increased total protein, globulin, Ca, and P concentrations. Average concentrations (mg/dL) were 260, 297, and 305 for glucose; 6.28, 8.09, and 7.58 for total protein; 1.98, 2.48, and 2.38 for albumin; 4.30, 5.62, and 5.19 for globulin; 0.40, 0.52, and 0.54 for creatine; 16.0, 16.5, and 16.3 for Ca; and 6.27, 8.14, and 7.17 for P in hens supplemented with 0, 0.15, and 0.30% probiotic, respectively. There was no effect of CD on egg quality. Increasing level of PS linearly improved yolk color (YC) and quadratically increased albumen index (AI) and Haugh unit (HU). The mean values were 9.67, 9.75, and 10.58 for YC; 8.94, 6.93, and 8.72% for AI; and 85.6, 74.9, and 82.9 for HU for hens supplemented with 0, 0.15, and 0.30% probiotic, respectively. There was also CD by PS effect on FC, EP, and serum glucose, total protein, albumin, globulin, creatine, Ca and P concentrations. In conclusion, increased CD partially depressed laying performance and caused stress. Probiotic supplementation improved laying performance and metabolic profile. It also partially alleviated the adverse effects of stress resulting from increased caging density.

• Journal of Korean Neurosurgical Society
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• v.54 no.6
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• pp.496-500
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• 2013

Objective : To evaluate the successful fusion rate in postmenopausal women with single-level anterior cervical discectomy and successful fusion (ACDF) and identify the significant factors related to bone successful fusion in pre- and postmenopausal women. Methods : From July 2004 to December 2010, 108 consecutive patients who underwent single-level ACDF were prospectively selected as candidates. Among these, the charts and radiological data of 39 women were reviewed retrospectively. These 39 women were divided into two groups : a premenopausal group (n=11) and a postmenopausal group (n=28). To evaluate the significant factors affecting the successful fusion rate, the following were analyzed : the presence of successful fusion, successful fusion type, age, operated level, bone mineral density, graft materials, stand-alone cage or plating with autologous iliac bone, subsidence, adjacent segment degeneration, smoking, diabetes mellitus, and renal disease. Results : The successful fusion rates of the pre- and postmenopausal groups were 90.9% and 89.2%, respectively. There was no significant difference in the successful fusion rate or successful fusion type between the two groups. In the postmenopausal group, three patients (10.8%) had successful fusion failure. In the postmenopausal group, age and subsidence significantly affected the successful fusion rate (p=0.016 and 0.011, respectively), and the incidence of subsidence in patients with a cage was higher than that in patients with a plate (p=0.030). Conclusion : Menopausal status did not significantly affect bone successful fusion in patients with single-level ACDF. However, in older women with single-level ACDF, the combination of use of a cage and subsidence may unfavorably affect successful fusion.