• The KSFM Journal of Fluid Machinery
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• v.8 no.3 s.30
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• pp.33-41
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• 2005

The optimum condition is defined as one that best suits the purpose of flocculation; the number of small particles should decrease, while that of large particles should increase. The object of this research was to develop a new impeller and substitute for conventional flocculators. The flow characteristics of turbines and hydrofoil type flocculators in turbulent fluids were observed using a standard $k-{\epsilon}$ Model and a computational fluid dynamics (CFD) simulation program-FLUENT. The experiments were performed to compare PBT(Pitched Blade Turbine) flocculator with twisted hydrofoil type flocculators for velocity distribution, and floe formation at conventional water treatment plants in Korea. As a result of the CED solution, twisted hydrofoil types are similar to hydrofoil flocculators for flow characteristics without regard to the twisted angle, On the other hand, it was established that turbine flocculators are greater than hydrofoil flocculators with flow unevenness and dead zone formation. Twisted hydrofoil type-II (Angle $15{\sim}20^{\circ}$) is the most proper impeller for water flocculation from this point of view with a decreasing the dead zone, maintaining of the equivalent energy distribution and a drawing up of the sedimentation substance from the bottom of the flocculation basin.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.802-810
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• 2007

Fibrobacter succinogenes, a Gram-negative, anaerobic ruminal bacterium is a major fibre digesting species in the rumen. It intensively degrades plant cell walls by an erosion type of mechanism, burrowing its way through the complex matrix of cellulose and hemicellulose with the release of digestible and undigested cell wall fragments. The enzymes involved in this process include a combination of glucanases, xylanases, arabinofuranosidase(s) and esterases. The genome of the bacterium has been sequenced and this has revealed in excess of 100 putative glycosyl hydrolase, pectate lyase and carbohydrate esterase genes, which is greater than the numbers reported present in other major cellulolytic organisms for which genomes have been sequenced. Modelling of the amino acid sequences of two glycanases, CedA and EGB, by reference to crystallized homologs has enabled prediction of the major features of their tertiary structures. Two dimensional gel electrophoresis in conjunction with mass spectroscopy has permitted the documentation of proteins over expressed in F. succinogenes grown on cellulose, and analysis of the cell surfaces of mutant strains unable to bind to cellulose has enabled the identification of candidate proteins with roles in adhesion to the plant cell wall substrate, the precursor to cellulose biodegradation.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.1
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• pp.73-78
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• 2014

Cell death and survival are tightly controlled through the highly coordinated activation/inhibition of diverse signal transduction pathways to insure normal development and physiology. Imbalance between cell death and survival often leads to autoimmune diseases and cancer. Death receptors sense extracellular signals to induce caspase-mediated apoptosis. Acting upstream of CED-3 family proteases, such as caspase-3, Bcl-2 prevents apoptosis. Using short hairpin RNAs (shRNAs), we suppressed Bcl-2 expression in Jurkat T cells, and this increased TCR-triggered AICD and enhanced TNFR gene expression. Also, knockdown of Bcl-2 in Jurkat T cells suppressed the gene expression of FLIP, TNF receptor-associated factors 3 (TRAF3) and TRAF4. Furthermore, suppressed Bcl-2 expression increased caspase-3 and diminished nuclear factor kappa B (NF-${\kappa}B$) translocation.

• Journal of Korean Academy of Nursing
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• v.41 no.6
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• pp.805-813
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• 2011

Purpose: The purpose of this study was to examine the effectiveness of an interpersonal relationship program on interpersonal relationships, self-esteem, and depression in nursing students. Methods: This was a quasi-experiment with a nonequivalent control group pre-posttest design. Sixty-four nursing students participated in the study with 31 in the experimental group and 33 in the control group. They were from 3 different colleges of nursing located in Seoul. The interpersonal relationship program was held 10 times over 10 weeks, taking 90 minutes per session. The interpersonal relationship change scale developed by Schlein and Guemey, Rosenberg's self-esteem scale, and CED-S for depression were the instruments used in the study. The data collection period was from January 4 to March 8, 2011, and the collected data were analyzed with SPSS 14.0 using the $X^2$-test, t-test, and paired t-test. Results: The results showed a significant difference between the experimental group and the control group in terms of the degree of interpersonal relationships, self-esteem, and depression. Conclusion: The results indicate that interpersonal relationship programs have positive effects for improving interpersonal relationships and self-esteem, and decreasing depression in nursing students.

• Research in Community and Public Health Nursing
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• v.19 no.1
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• pp.5-12
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• 2008

Objectives: The study was to examine major factors that affect suicidal ideation of elderly in urban areas. Methods: The subjects were 302 elders who voluntarily participated in the study. The instruments for this study were scale for suicidal ideation(19 items), family concord (20 items), CED-depression(20 items) and family inventor of life events and changes(FILE, 22 items). Frequency, percentage, t-test, ANOVA, Duncan test, Pearson' correlation coefficient, stepwise multiple regression with SPSS program were used to analyze the data. Results: The average score of suicidal ideation was 14.88. Suicidal ideation was positively related to depression and stress, but negatively related to family concord, depression, family concord, stress and health status accounted for 86.1% of the variance in suicidal ideation. These results suggest that family concord, depression and stress can be potential risk factors for suicide of elderly. Conclusions: These findings may give useful information for developing suicidal prevention program on old age.

• Korean Journal of Biological Psychiatry
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• v.5 no.2
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• pp.219-226
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• 1998

Cytosine arabinoside(AraC) inhibits DNA synthesis and ${\beta}$-DNA polymerase, an enzyme involved in DNA repair. This, a potent antimitotic agent, is clinically used as an anticancer drug with side effect of severe neurotoxicity. Earlier reports suggested that inhibition of neuronal survival by AraC in sympathetic neuron may be due to the inhibition of a 2'-deoxycytidine-dependent process that is independent of DNA synthesis or repair and AraC induced a signal that is triggers a cascade of new mRNA and protein synthesis, leading to apoptotic cell death in cultured cerebellar granule cells. The present study would suggest whether caspase family(ICE/CED-3-like protease) involved in AraC-induced apoptosis pathway of PC12 cells. It was observed that treatment of PC12 cells with AraC led to decrease of viability by MTT assay and morphology changes, which did not suggest that AraC induced apoptosis in PC12 cells. The mRNA of caspase-1/caspase-3 were expressed in PC12 cells constitutively, and AraC did not activate caspase family. These results suggest that caspase-1/caspase-3 may not be required for AraC-induced cell death pathway in PC12 cells.

• Journal of the Korean Professional Engineers Association
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• v.27 no.2
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• pp.42-54
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• 1994

Nowadays communication network is steadily changing from a main body of telephone to a network which is creating new services such as multimedia etc. Jhis article introduces a bud of new service and new network which are able to sustain the above service. Including Korea, world advanced countries have been digitatizing their network with N-ISDN (narrowband ISDN) by e.g. 64K b/s and 1.5M b/s. New service by N-ISDN are extraordinary, though it can not solve all kinds of services. To solve these problems, a solving platform should be constituted. B-ISDN(broadband ISDN), as a platform has to be built to deal with almost all uinds of services, whatever the communication speed, communication mode or communication quality may be. Korea Telecommunication Authority(KTA) opened the narrowband ISDN(N-ISDN) at the end of 1993. This was one step previous opening of the broadband ISDN(B-ISDN) service scheduled to be rendered in 2001. B-ISDN, receiving and transmitting by far more information with high speed than the N-NSDN does, is one of G-7 Progects which the Korean government is driving foreward to raise the national scientific power to seven advan ced countries. This is also linked with an extremely high speed information network scheduled to be built by the Ministry of Communications in 2015.

• Korean Journal of Community Nutrition
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• v.6 no.4
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• pp.628-634
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• 2001

This study was conducted to investigate the relationship of serum calcium and magnesium level to depression and anxiety symptoms in 66 perimenopausal women. Daily nutrient intakes and dietary sources of calcium were analyzed by convenient me쇙. General status was conducted by a questionnaire whereas the questionnaire of CED-S(the Center for Epidemiological studies-Depression Scale) was used for depression and Spielburger's STAI-S(state-Trait Anxiety Inventory-State) was used for anxiety. Fasting blood samples were collected, and serum calcium and magnesium concentrations were measured before and after calcium supplementation. The age distribution of the subjects was 49-55 years. Results indicated that serum calcium concentrations were significantly(P〈0.05) increased to normal ranges after calcium supplementation. Depression and anxiety scores of the subjects with calcium supplementation were significantly(p〈0.05) lower than those before calcium supplementation. There were significantly(P〈0.05) decreased between serum magnesium concentration and depression and anxiety scores, but calcium concentration was not significantly decreased. These results suggest that psychological conditions of perimenopausal women are possibly effected by serum calcium and magnesium levels. More studies are needed to measure the long-term effects of calcium supplementation on psychological conditions in perimenopausal women.

• Journal of Veterinary Clinics
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• v.38 no.2
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• pp.98-102
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• 2021

Three dogs with different extents of corneal edema were presented to the Dana Animal Hospital Eye Center. The dogs (3 eyes) were diagnosed with corneal endothelial degeneration with clinical signs of corneal edema, conjunctival hyperemia, and mild blepharospasm through a full ophthalmic examination. For the treatment of corneal edema, superficial keratectomy using a crescent microsurgical knife was performed, and a conjunctival advancement hood flap was applied to the stromal defects. In two cases where corneal edema and opacity were observed only in a part of the cornea, corneal edema was reduced and did not progress to other parts of the cornea and corneal transparency and vision were also well-maintained during the follow-up on days 349 and 231 after the surgery. In a case where the whole cornea was edematous and cloudy, corneal edema and opacity had not clearly improved at the last follow-up on day 275 after the surgery. In conclusion, SKCAHF relieved corneal edema and improved vision, and the prognosis tended to be better when there was less corneal edema caused by CED.

• Archives of Pharmacal Research
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• v.23 no.1
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• pp.1-16
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• 2000

Many natural products elicit diverse pharmacological effects. Using two classes of potential chemopreventive compounds, the phenolic compounds and the isothiocyanates, we review the potential utility of two signaling events, the mitogen-activated protein kinases (MAPKs) and the ICE/Ced-3 proteases (caspases) stimulated by these agents in mammalian cell lines. Studies with phenolic antioxidants (BHA, tBHQ), and natural products (flavonoids; EGCG, ECG, and isothiocyanates; PEITC, sulforaphane), provided important insights into the signaling pathways induced by these compounds. At low concentrations, these chemicals may activate the MAPK (ERK2, JNK1, p38) leading to gene expression of survival genes (c-Fos, c-Jun) and defensive genes (Phase II detoxifying enzymes; GST, QR) resulting in survival and protective mechanisms (homeostasis response). Increasing the concentrations of these compounds will additionally activate the caspase pathway, leading to apoptosis (potential cytotoxicity). Further increment to suprapharmacological concentrations will lead to nonspecific necrotic cell death. The wider and narrow concentration ranges between the activation of MAPK/gene induction and caspases/cell death exhibited by phenolic compounds and isothiocyanates, respectively, in mammalian cells, may reflect their respective therapeutic windows in vivo. Consequently, the studies of signaling pathways elicited by natural products will advance our understanding of their efficacy and safety, of which many man become important therapeuitc drugs of the future.