• Journal of Nutrition and Health
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• v.29 no.6
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• pp.590-593
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• 1996

This study was done to evaluate the effect of dietary calcium level (a diet which met 100% or twice the calcium level in AIN-76 diet) on preventing bone loss in ovariectomized rats. Forty Sprauge-Dawley female rats(body weight 200$\pm$5g)were divided into two groups. One group were ovariecotomized (Ovx) while the others received sham operation(Sham). Thereafter, each rat group was further divided into normal calcium diet(0.52%) and high calcium diet(1.04%) subgroups. All rats were fed on experimental diet and deionized water ad libitum for 8 weeks. The total body, spine and femur bone mineral densities and bone mineral contents were measured by Dual Energy X-ray Absorptiometry, Eight weeks following operation, ovariectomized rats fed a high calcium diet had a significantly higher total bone mineral content, total bone calcium content, spine bone mineral density, spine bone mineral content and femur bone mineral content than ovariectomized rats fed control calcium diet. The correlation between dietary calcium intake level and spine bone mineral density were positive, but there was no correlation between dietary calcium intake and femur bone mineral density. The findings from the present study demonstrated that bone loss due to ovarian hormonal deficiency can be partially prevented by a high calcium diet. Futhermore, these findings support the strategy of the use of a high calcium diet in the prevention of estrogen depleted bone loss(postmenopausal osteoporosis)

• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.101-107
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• 1997

High strength concrete(HSC) using high range water reducing admixture (HRWR) has the defect which severe slump loss occurs according to elapsed time. For using HSC without any trouble, special caution and countermeasure against this problem are necessary. In this study, for minimizing the slump loss of HSC, mineral admixture( flyash, ground granulated blast furnace slag ) and gypsum were used experimentally. Flyash and ground granulated blast furnace slag are effective in reducing the slump loss of HSC. Especially, the slump loss of HSC containing mineral admixture and gypsum Is minimized by the aggregation inhibiting action of gypsum. Cement substituted with flyash 30% or ground granulated blast furnace slag 50% by weight are very effective in minimizing the slump loss.

• Journal of Korean Academy of Nursing
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• v.41 no.6
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• pp.758-767
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• 2011

Purpose: This study was done to examine the threshold value of estimated height loss at which the risk of osteoporosis increases and to verify its discriminative ability in the detection of osteoporosis. Methods: It was conducted based on epidemiological descriptive methods on 732 Korean women at a public healthcare center in Seoul between July and November 2010. ANOVA, Pearson correlation, logistic regression analysis and receiver operating characteristics (ROC) curve were used for data analysis. Results: There was an age-related correlation between bone mineral density (lumbar spine: F=37.88, p<.001; femur: F=54.27, p<.001) and estimated height loss (F=27.68, p<.001). Estimated height loss increased significantly with decreasing bone mineral density (lumbar spine: r=-.23, p<.001; femur: r=-.34, p<.001). The odds ratio for the point at which the estimated height loss affects the occurrence of osteoporosis was found to increase at a cut-off value of 2 cm and the area under ROC curve was .71 and .82 in lumbar spine and femur, respectively. Conclusion: The optimal cut-off value of the estimated height loss for detection of osteoporosis was 2 cm. Height loss is therefore a useful indicator for the self-assessment and prognosis of osteoporosis.

• Journal of Soil and Groundwater Environment
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• v.28 no.4
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• pp.1-5
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• 2023

In the fabrication of magnetic adsorbent by incorporating iron species on base materials with layered structure, there can be a potential loss of adsorption capacity from the penetration of dissolved iron species into the structure. This work newly synthesized a magnetic adsorbent by incorporating nano magnetite and glucose into layered metal sulfide via hydrothermal treatment, and tested the removal efficiencies of cesium ions (Cs⁺) by the adsorbents fabricated under different conditions (final temperature and glucose mass ratio). As a result, the optimal fabrication condition was found to be mass ratio of 1 (layered metal sulfide): 0.1 (nano magnetite): 0.4 (glucose) and final temperature of 160℃. As-prepared adsorbent possessed good adsorption ability of Cs⁺ (54.8 mg/g) without a significant loss of adsorption capacity from attaching glucose and nano magnetite onto the surface.

• Natural Product Sciences
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• v.6 no.4
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• pp.155-160
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• 2000

Testosterone deficiency increased bone resorption, giving rise to osteoporosis. Testosterone deficiency also increased lipid peroxidation and free radical formation. Free radicals have been shown to be toxic to osteoblasts as well as to activate osteoclasts. In this study, the effects of giving an antioxidant, i.e. vitamin E-rich extract from palm oil on bone mineral density and calcium content was studied. Palm vitamin E prevented the loss in bone mineral density due to orchidectomy, seen in the whole femur, proximal amd midshaft regions, as well as L4 vertebra. Similar observations were seen in bone calcium content of the L5 vertebra. Giving palm olein also prevented the loss in bone mineral density in the femoral midshaft and L4 vertebra; and bone calcium content in the L5 vertebra. In conclusion, vitamin E-rich extract from palm oil was effective in preventing the loss in bone mineral density and calcium content of orchidectomized male rats. This action is probably due to its role as an antioxidant.

• Physical Therapy Korea
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• v.16 no.4
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• pp.31-36
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• 2009

Hemiplegia-induced immobilizatoin and reduction of mechanical loading in chronic stroke limbs are common cause of disuse osteoporosis. The purpose of this study was to investigate the effects of asymmetrical weight bearing on the loss of bone mineral in the individual with chronic stroke. Sixteen hemiplegic patients with strokes were evaluated. The measurements of bone mineral density (BMD) were evaluated with the quantitative ultrasound system on the calcaneus region of the paretic and non-paretic side. Plantar pressure was measured using the Mat-Scan system. The paretic side showed significantly smaller values in the T-score of BMD, and peak value of plantar pressure, which included forefoot, midfoot, and hindfoot, than the non-paretic side (p<.05). Results from the pearson correlation analysis showed statistically significant correlation between the BMD difference and the peak-pressure difference of midfoot pressure (p<.05). This finding indicated that BMD loss depended on decrease of body weight born on the paretic leg.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.707-710
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• 2005

This experimental study investigate temperature dependency affecting setting and strength development of concrete using mineral admixtures such as CKD, FA and BS. For the properties of setting at $5^{\circ}C$, setting time of concrete with mineral admixture was delayed about $3\~14$ hour compared with that of plain concrete. Use of CKD had a desirable effect on reducing setting retard under $5^{\circ}C$ because of $CaCO_3$ of CKD while use of FA and BS retarded setting time greatly. For compressive strength under $5^{\circ}C$, concrete with CKD had the most compressive strength in early age compared with the other mineral admixtures but exhibited slight strength loss in $-5^{\circ}C$ at 28days. Especially, concrete with FA and BS was observed in early stage at low curing temperature because of strength loss remarkably in $-5^{\circ}C$.

• Journal of dental hygiene science
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• v.18 no.4
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• pp.265-270
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• 2018

The purpose of this study was to investigate the chemical properties of some commercially available mouthwashes and to ascertain whether the mouthwashes accelerated mineral loss in dental enamel. Five commercially available mouthwashes were selected from the three largest malls in Korea: Perio Total 7 Aqua Cool Mint Strong $Fresh^{TM}$ (PS; LG Household & Health Care Ltd.), Garglin $Original^{TM}$ (Dong-A Pharmaceutical Co., Ltd.), Garglin $Zero^{TM}$ (Dong-A Pharmaceutical Co., Ltd.), Listerine Naturals $Citrus^{TM}$ (LC; IDS Manufacturing Ltd.), and Listerine Cool $Mint^{TM}$ (LM; IDS Manufacturing Ltd.). The composition, pH, and titratable acidity of the mouthwashes were investigated. Six bovine teeth specimens were prepared for each mouthwash group. Each of the six specimens was individually immersed in 30 ml aliquots of mouthwash for 1 minute, 30 minutes, 90 minutes, and 120 minutes, and the samples were placed in a $36.5^{\circ}C$ stirred incubator. The degree of mineral loss (${\Delta}F$) of the tooth surface area exposed to mouthwash, compared with normal teeth, was analyzed by quantitative light-induced fluorescence-digital. The difference in ${\Delta}F$ among mouthwash groups was examined by the Kruskal-Wallis H test (${\alpha}=0.05$). The contents of mouthwashes differed between Listerine and other products, and the pH ranged from 4.09 to 6.75. The titratable acidity of PS was the lowest at 0.63 ml and highest at 9.25 ml for LM. Minor mineral loss was observed when dental specimens were immersed in the Listerine products (LC and LM) for more than 90 minutes, but the degree of mineral loss for Listerine products was not statistically significantly different from that for groups without mineral loss. In conclusion, all five commercially available mouthwashes showed no harmful effects on tooth enamel.

• Resources Recycling
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• v.31 no.2
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• pp.40-48
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• 2022

In this study, the effects of solution components were investigated in the recovery of vanadium as ammonium metavanadate from vanadium-ore-salt roasting-water leaching solution. The vanadium-containing solution is strongly alkaline (pH 13), so the pH must be lowered to 9 or less to increase the ammonium metavanadate precipitation efficiency. However, in the process of adjusting the solution pH using sulfuric acid, aluminum ions are co-precipitated, which must be removed first. In this study, aluminum was precipitated in the form of an aluminum-silicate compound using sodium silicate, and the conditions for minimizing vanadium loss in this process were investigated. After aluminum removal, the silicate was precipitated and removed by adjusting the solution pH to 9 or less using sulfuric acid. In this process, the concentration and addition rate of sulfuric acid have a significant influence on the loss of vanadium, and vanadium loss was minimized as much as possible by slowly adding dilute sulfuric acid. Ammonium metavanadate was precipitated using three equivalents of ammonium chloride at room temperature from the aluminum-free, aqueous solution of vanadium following the pH adjustment process. The recovery yield of vanadium in the form of ammonium metavanadate exceeded 81%. After washing the product, vanadium pentoxide with 98.6% purity was obtained following heat treatment at 550 ℃ for 2 hours.

• Biomolecules & Therapeutics
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• v.16 no.2
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• pp.141-146
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• 2008

Imbalance in calcium and phosphorous metabolism due to aging or menopause leads to osteoporosis. In contrast to patients with normal blood pressure, hypertensive patients have a higher loss of calcium in the urine with its attendant risk of osteoporosis. The high blood pressure is associated with the risk of bone loss and abnormalities in calcium metabolism leading to calcium loss. So we retrospectively investigated the changes of bone mineral density (BMD) which drugs can have clinical influences over osteoporosis treatments of patients with calcium-antagonists as common antihypertensive drugs and with bisphosphonates which causes a most effective inhibition of osteoclasts resorption. As a result over 70 years of age group and within bisphosphonates group, alendronate 70 mg once-weekly group showed significant increase of BMD in lumbar area. Combination group of cilnidipine and $maxmarvil^{(R)}$ showed very significant decrease of BMD. In conclusion, it is desirable that combination therapy with calcium-antagonists is used carefully in the treatment of osteoporosis with high blood pressure.