• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.11
• /
• pp.1534-1541
• /
• 2001

Forty-five Large White gilts were used to study the effect of energy intake from 28 to 176 d of age on body composition and reproductive development. From 28 to 60 d, the gilts were fed ad libitum a 16.6 MJ DE/kg, 24% crude protein and 1.3% total lysine diet. From 61 d of age three dietary treatments were used; 1) ad libitum access to feed (15.6 MJ DE/kg, 21% crude protein and 1.07% total lysine) (H), 2) feed offered at 75% (M) of the previous days intake of H, and 3) feed offered at 60% (L) of the previous days intake of H. ADG from 61 to 176 d of age was (p<0.05) affected by treatment. Although live weight at 176 d of age did not differ (p>0.1) the H gilts had higher (p<0.08) carcass weights than the M or L gilts. Back fat depths were similar (p>0.1) for all treatments at 115 d of age, however by 176 d of age M and H gilts were fatter (p<0.1) than L gilts. The mean lipid deposition (LD) from 115 to 176 d of age for L gilts (78.9 g/d) was less (p<0.05) than for M gilts (143.6 g/d) and H gilts (135.6 g/d). There were no differences between treatments for protein deposition (PD) over the same period. More (p<0.05) H gilts (n=8) attained puberty (first observed estrus) than either M gilts or L gilts (n=4 for both). Follicle numbers were similar (p>0.1) across treatments. For gilts that attained puberty, H gilts had fewer (p<0.05) follicles (13.5) than M gilts (19.7) and L gilts (21.3). For gilts with follicular development, H gilts had the heaviest (458.7 g) reproductive tract weight (RTW). However, for those that attained puberty, L gilts had the heaviest RTW. RTW were lowest for those with no follicular development. Energy restriction had a negative impact on puberty attainment, i.e. it took longer to reach puberty. However, for gilts that attained puberty, the number of follicles was greater for those on r feed intakes. It would appear that rate of fat deposition, but not necessarily the total amount of fat, plays an important role in puberty attainment.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.9
• /
• pp.5435-5440
• /
• 2013

Background: Recent estimates suggest that in the Lao People's Democratic Republic (Lao PDR) the burden of cancer in terms of DALYs lost is amongst the highest in South East Asia. As such, increasingly cancer is becoming an important public health concern in the country. Lao PDR however has no population-based cancer registry and only one hospital-based registry. Cancer treatment within the country is extremely limited. Patients who can, may travel to neighboring countries for treatment, but little information about this is available in the country. The aim of this study was to estimate some of the otherwise largely unknown parameters of the cancer burden in Lao PDR. Materials and Methods: This is a retrospective, descriptive study based on the records of 847 Lao cancer cases treated with surgery, radiation and chemotherapy at Srinagarind Hospital, Khon Kaen University, in Thailand between 1988 and 2010. Results: The annual rate of registration of Lao cancer cases fluctuated, but showed an increasing trend. Most cancers were diagnosed by histology (65.2%), and a combination of endoscopy and radiology (15.6%). In most cases (70.2%) the stage of cancer at diagnosis could not be determined. In those whose stage could be identified, 54.0% were at the final stage (Stage IV). Among males, the commonest cancer sites were the liver (16.1%), blood (12.3%) and nasopharynx (10.6%). Those in female patients were the cervix (22.2%), breast (14.6%) and blood (8.1%). Conclusions: This study indicates that despite some fluctuations, the number of Lao cancer patients presenting at Srinagarind Hospital, Khon Kaen, gradually increased between 1988 and 2010. The unfavorable pattern of late-stage cancer diagnosis among male and female patients suggests a need for cancer control interventions and the establishment of cancer registration and treatment facilities within Lao PDR.

• Korean Journal of Materials Research
• /
• v.23 no.4
• /
• pp.227-232
• /
• 2013

Al-based alloys have recently attracted considerable interest as structural materials and light weight materials due to their excellent physical and mechanical properties. For the investigation of the potential of Al-based alloys, a surface porous $Al_{88}Cu_6Si_6$ eutectic alloy has been fabricated through a chemical leaching process. The formation and microstructure of the surface porous $Al_{88}Cu_6Si_6$ eutectic alloy have been investigated using X-ray diffraction and scanning electron microscopy. The $Al_{88}Cu_6Si_6$ eutectic alloy is composed of an ${\alpha}$-Al dendrite phase and a single eutectic phase of $Al_2Cu$ and ${\alpha}$-Al. We intended to remove only the ${\alpha}$-Al phase and then the $Al_2Cu$ phase would form a porous structure on the surface with open pores. Both acidic and alkaline aqueous chemical solutions were used with various concentrations to modify the influence on the microstructure and the overall chemical reaction was carried out for 24 hr. A homogeneous open porous structure on the surface was revealed via selective chemical leaching with a $H_2SO_4$ solution. Only the ${\alpha}$-Al phase was successfully leached while the morphology of the $Al_2Cu$ phase was maintained. The pore size was in a range of $1{\sim}5{\mu}m$ and the dealloying depth was nearly $3{\mu}m$. However, under an alkaline NaOH, aqueous solution, an inhomogeneous porous structure on the surface was formed with a 5 wt% NaOH solution and the morphology of the $Al_2Cu$ phase was not preserved. In addition, the sample that was leached by using a 7 wt% NaOH solution crumbled. Al extracted from the Al2Cu phase as ${\alpha}$-Al phase was dealloyed, and increasing concentration of NaOH strongly influenced the morphology of the $Al_2Cu$ phase and sample statement.

• Proceedings of the Microbiological Society of Korea Conference
• /
• 2008.05a
• /
• pp.42-44
• /
• 2008

Bacterial biofilms are analogous to multi-cellular organisms or to clonal communities of higher organisms. In this respect, it can be demonstrated that biofilms display the type of genetic variation associated with macroorganisms. The formation of genetic variants from biofilms is the result of internally produced and regulated signals and the appearance of these variants coincides with dispersal from the biofilm. Moreover, the generation of such variation, has similar outcomes for the bacterial community, where diversification of phenotypic traits ensures that the bacterial community optimizes its chances of success when dispersing or surviving when challenged with environmental stress. These observations increase the complexity with which we view bacteria and also suggest that microbial systems can serve as models for the testing of eukaryotic ecological theories.

• Korean Journal of Clinical Laboratory Science
• /
• v.36 no.2
• /
• pp.163-172
• /
• 2004

Mast cells (MCs) have been implicated in the pathogenesis of tissue fibrosis. However, the role of MC in the development of liver fibrosis has not been fully elucidated. Stem cell factor (SCF) is known to recruit MCs to the liver following injury as it induces mast cell proliferation, survival and differentiation from resident tissue precursors. This study examines the interaction between activated hepatic stellate cells (HSCs) and MCs in rat fibrotic liver, and SCF production by HSCs during culture in vitro. Rats were studied 4, 7, 14 and 21 days after bile duct ligation (BDL). Fibrogenesis was assessed by a measurement of collagen stained with sirius red F3B. Activated HSCs and MCs were identified by ${\alpha}$-smooth muscle actin (${\alpha}-SMA$) immunohistochemical and alcian blue staining and measured by a computerized image analysis system. SCF production was determined in rat HSC cultures using Western blotting. Mild fibrotic changes were noted in BDL rat livers as early as 4 days after induction of cholestasis. Significant expansion and organization of fibrous tissue has occurred in day 14 BDL rats which progressed to bridging fibrosis by day 21. In BDL rats, both a large number of activated HSCs and MCs were detected in portal tracts and fibrous septa. Both area of activated HSCs infiltration and density of MCs were significantly higher in all BDL group compared with Shams. In BDL rats, both areas of activated HSCs infiltration and density of MCs were no significant difference between day 4 and 7 and were significantly higher in day 14. However, the areas of activated HSCs infiltration were significantly lesser in day 21 and the densities of MCs were significantly higher in day 21 compared with day14 BDL. In BDL rats, both areas of activated HSCs infiltration and density of MCs were highly correlated with areas of fibrosis. Western blotting showed that SCF protein was consistently produced in activated HSCs by culture on plastic and freshly isolated HSCs expressed relatively little 30kD SCF compared to late primary culture activated HSCs (day 14) and passaged HSCs. These results suggest that HSCs activated in vitro produce SCF, and may play an important role in recruiting mast cells to the liver during injury and fibrosis.

• Journal of Life Science
• /
• v.27 no.11
• /
• pp.1262-1268
• /
• 2017

Lemon myrtle (Backhousia citriodora), a plant in the Myrtaceae family, is native to the semitropical rain-forests of Queensland and is presumably the most commercialized native spice. In Australian thousands of lemon-myrtle trees are under tillage. This study was carried out to investigate the alcohol metabolism, hepatoprotective effects and antidiabetic, tyrosinase inhibitory activity of hot-water (LMW) and 80% ethanol (LME) extracts from lemon-myrtle leaves. The alpha-glucosidase (${\alpha}$-glucosidase) inhibitory activities of the LMW and LME extracts were 7.66% and 40.29% at 1 mg/ml (p<0.05), respectively. The tyrosinase inhibitory activity of the LME extract was about 38.26 % at 1 mg/ml. The effects the LMW and LME extracts had on alcohol-metabolizing activities were determined by measuring the generation of reduced nicotinamide-adenine dinucleotide (NADH) by acetaldehyde dehydrogenase (ALDH) and alcohol dehydrogenase (ADH). The ADH activities of the LMW and LME extracts significantly increased in a dose-dependent manner and were about 154.40% and 192.03% at 1 mg/ml, respectively (p<0.05). The ALDH activities of the LMW and LME extracts also significantly increased in a dose-dependent manner and were about 151.14% and 192.34% at 1 mg/ml, respectively (p<0.05). At $100{\mu}g/ml$, the LMW and LME extracts showed significant protective effects against tacrine-induced cytotoxicity in Hep G2 cells. The results suggested that Backhousia citriodora leaf extracts have the potential to be significant sources for natural health products.

• Journal of Korean Ophthalmic Optics Society
• /
• v.13 no.2
• /
• pp.43-50
• /
• 2008

Purpose: The purpose of this study is to evaluate the effect of a VR (Virtual Refractor), which is a simulator for a PR (Practical Refraction), as an educational tool. Methods: Twenty four third year students enrolled in the department of visual optics volunteered for VR education. Each student attended a VR training course and practiced with the VR by themselves. One month later, each student tested three virtual subjects on the VR and one real subject on the PR and were given a performance score for each refraction. And the scores for the virtual and practical refractions were compared. In addition, a self-report questionnaire based on a five point Likert-scale was designed, consisting of domains such as spontaneous participation, contribution for the refraction, confirmity of the VR and PR, and necessity of the VR. Results: The Spearman's correlation coefficient between the testing score of the practical and virtual refractions indicated a significantly correlation (R=0.71, p<0.001). In the questionnaire, the mean score of the domains was 3.67${\pm}$0.96 and it indicated that students expressed that using the VR was beneficial. The correlation value among these domains was a high significant level, 0.91~0.68 (p<0.001). Conclusions: Although the VR required certain improvements in its concentration and systematic approaches for practical situations, it showed a high correlation between the VR and the PR and represented a positive evaluation in the PR.

• Clean Technology
• /
• v.18 no.1
• /
• pp.63-68
• /
• 2012

In this study, aluminum hydroxide ($Al(OH)_3$) was synthesized by Bayer process and sodium contained in $Al(OH)_3$ was removed with the acid solution such as HCl and acetic acid for the synthesis of high purity alumina. The bauxite produced in Queensland of Australia was used for the production of alumina by Bayer, and was crushed to a particle size of below 10 um by attrition mill. The crushed bauxite was treated in sodium hydroxide solution of 5 N for the elution of aluminum component. The elution of aluminum from bauxite was carried out at $140^{\circ}C$ and 3.4 atm in autoclave. The sample solution was separated to the red mud and liquid solution by filter paper. The elution of aluminum from bauxite was confirmed with changing a structure and aluminum content in both bauxite and red mud analyzed by XRD and EDX. Aluminum contained in the separated solution was crystallized to $Al(OH)_3$ with the addition of aluminum hydroxide used as the seed material. $Al(OH)_3$ powder obtained during the crystallization process was purified by several times washing with distillated water. It was also confirmed that the sodium remained in $Al(OH)_3$ powder is removed with acid solution. The purity of $Al(OH)_3$ powder produced in this study was 99.3% and the content of sodium was reduced to approximately 0.009% after the acid treatment.

• Environmental Engineering Research
• /
• v.13 no.3
• /
• pp.125-130
• /
• 2008

Free ammonia ($NH_3$-N) inhibition of nitrite-oxidizing bacteria (NOB) has been widely studied for partial nitrification (or nitrite accumulation) and denitrification via nitrite ($NO_2^-$-N) as a low-cost treatment of ammonium containing wastewater. The literature on $NH_3$-N inhibition of NOB, however, shows disagreement about the threshold $NH_3$-N concentration and its degree of inhibition. In order to clarify the confusion, a simple and cheap respirometric method was devised to investigate the effect of free ammonia inhibition of NOB. Sludge samples from an autotrophic nitrifying reactor were exposed to various $NH_3$-N concentrations to measure the maximum specific nitrite oxidation rate ($\hat{K}_{NO}$) using a respirometer. NOB biomass was estimated from the yield values in the literature. Free ammonia inhibition of nitrite oxidizing bacteria was reversible and the specific nitrite oxidation rate ($K_{NO}$) decreased from 0.141 to 0.116, 0.100, 0.097 and 0.081 mg $NO_2^-$-N/mg NOB h, respectively, as the $NH_3$-N concentration increased from 0.0 to 1.0, 4.1, 9.7 and 22.9 mg/L. A nonlinear regression based on the noncompetitive inhibition mode gave an estimate of the Inhibition concentration ($K_I$) of free ammonia to be 21.3 mg $NH_3$-N/L. Previous studies gave $\hat{K}_{NO}$ of Nitrobacter and Nitrospira as 0.120 and 0.032 mg/mg VSS h. The free ammonia concentration which inhibits Nitrobacter was $30{\sim}50\;mg$ $NH_3$-N/L and Nitrospira was inhibited at $0.04{\sim}0.08\;mg$ $NH_3$-N/L. The results support the fact that Nitrobacter is the dominant NOB in the reactor. The variations in the reported values of free ammonia inhibition may be due to the different species of nitrite oxidizers present in the reactors. The respirometric method provides rapid and reliable analysis of the behavior and community of the nitrite oxidizing bacteria.

• Research in Plant Disease
• /
• v.24 no.4
• /
• pp.302-307
• /
• 2018

From 2014 to 2016, approximately 5% of okra fruit were observed displaying gray mold symptoms at the research field of Jeollabuk-do Agricultural Research and Extension Services, Korea. The symptoms observed were water-soaked, brown or gray spots, and abundant mycelial with conidia appearing on the infected fruit. Initial infection commenced from the base of fruit and gradually moved to the pod, where it finally resulted in collapse. Colonies on potato dextrose agar were gray to grayish brown, felted and cottony expanding 65-80 mm after one week. The fungus formed several black sclerotia ranging $1.0-3.5{\times}0.5-3.0mm$ on the Petri dish after two weeks. The conidia were one-celled, ellipsoidal or ovoid, colorless or pale brown, and $6.2-15.4{\times}5.0-10.4{\mu}m$. Conidiophores arose solitary or in groups, straight or flexuous, septate, with an inflated basal cell brown to light brown, and measured $85-450{\times}10.0-40.0{\mu}m$. On the basis of the morphological characteristics and phylogenetic analyses of internal transcribed spacer rDNA, the fungus was identified as Botrytis cinerea Pers. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first report on the occurrence of B. cinerea on okra in Korea.