• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.941-948
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• 2020

Objective: This study was carried out to determine the effects of elevated dietary cation and anion difference (DCAD) on dry matter intake (DMI) and ruminal fermentation pattern in lactating dairy goats under tropical conditions. Methods: Ten dairy goats were divided into two groups of five animals each. The groups received diets at different DCAD levels, either a control diet (22.81 mEq/100 g dry matter [DM], DCAD-23) or a DCAD-39 diet (39.08 mEq/100 g DM, DCAD-39). After parturition, DMI and water intake were recorded daily. Ruminal fluid and urine were collected, and nutrient digestibility measurements were carried out at 8th weeks postpartum (PP-8). Blood samples were collected at PP-4 and PP-8 to measure plasma leptin. Results: Dry matter intake/body weight (DMI/BW) at PP-8 of the animals fed the DCAD-39 diet was significantly higher than those fed with DCAD-23 diet (p<0.05). Animals fed with DCAD-39 consumed more water than those fed DCAD-23 over 24 h, particularly at night (p<0.05). Ruminal pH, acetate concentration, and urinary allantoin excretion increased with the DCAD-39 diet, whereas ruminal butyrate concentration was lower with the DCAD-39 diet. On the other hand, other ruminal parameters, such as total volatile fatty acid concentration, propionate molar proportion and acetate/propionate average ratio, were not affected by increased DCAD supplementation. Apparent digestibility was improved by increased DCAD supplementation. Plasma leptin concentration was higher with DCAD supplementation. Conclusion: When feeding goats with DCAD-39 under tropical conditions, an increase in DMI was associated with improved apparent digestibility of nutrients, ruminal fermentation and microbial protein synthesis. An increase in plasma leptin concentration could not explain the effect of high DCAD on DMI.

• Korean Journal of Materials Research
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• v.20 no.6
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• pp.301-306
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• 2010

The chemical formula of magnetite ($Fe_3O_4$) is $FeO{\cdot}Fe_2O_3$, t magnetite being composed of divalent ferrous ion and trivalent ferric ion. In this study, the influence of the coexistence of ferrous and ferric ion on the formation of iron oxide was investigated. The effect of the co-precipitation parameters (equivalent ratio and reaction temperature) on the formation of iron oxide was investigated using ferric sulfate, ferrous sulfate and ammonia. The equivalent ratio was varied from 0.1 to 3.0 and the reaction temperature was varied from 25 to 75. The concentration of the three starting solutions was 0.01mole. Jarosite was formed when equivalent ratios were 0.1-0.25 and jarosite, goethite, magnetite were formed when equivalent ratios were 0.25-0.6. Single-phase magnetite was formed when the equivalent ratio was above 0.65. The crystallite size and median particle size of the magnetite decreased when the equivalent ratio was increased from 0.65 to 3.0. However, the crystallite size and median particle size of the magnetite increased when the reaction temperature was increased from $25^{\circ}C$ to $75^{\circ}C$. When ferric and ferrous sulfates were used together, the synthetic conditions to get single phase magnetite became simpler than when ferrous sulfate was used alone because of the co-existence of $Fe^{2+}$ and $Fe^{3+}$ in the solution.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.370-378
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• 1989

An Alkalophilic Bacillus circulans that can produce significant amount of cyclodextrin glucanotransferase (CGTase) was newly isolated from soil. The culture filtrate was successively purified by ($NH_4$)$_2$$SO_4$precipitation, DEAE-Sephadex column chromatography, and Sephadex G-100 column chromatography. The enzymatic properties, including molecular weight, optimal pH and temperature, stability, and kinetic parameters, were determined. The cyclodextrin synthesis reaction catalized by the purified CGTase was also studied. The sweet potato and corn starch were found to be the most suitable substrates with 60% conversion to cyclodextrin. The highest conversion was achieved at the CGTase concentration of 900-1,100 units/g of soluble starch. The purified CGTase could also catalize the transglycosylation on stevioside.

• The korean journal of orthodontics
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• v.48 no.4
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• pp.268-280
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• 2018

Resistance to sliding (RS) between the bracket, wire, and ligature has been largely debated in orthodontics. Despite the extensive number of published studies, the lack of discussion of the methods used has led to little understanding of this phenomenon. The aim of this study was to discuss variables affecting RS in orthodontics and to suggest an operative protocol. The search included $PubMed^{(c)}$, $Medline^{(c)}$, and the Cochrane $Library^{(c)}$. References of full-text articles were manually analyzed. English-language articles published between January 2007 and January 2017 that performed an in vitro analysis of RS between the bracket, wire, and ligature were included. Study methods were analyzed based on the study design, description of materials, and experimental setup, and a protocol to standardize the testing methods was proposed. From 404 articles identified from the database search and 242 records selected from published references, 101 were eligible for the qualitative analysis, and six for the quantitative synthesis. One or more experimental parameters were incompatible and a meta-analysis was not performed. Major factors regarding the study design, materials, and experimental setup were not clearly described by most studies. The normal force, that is the force perpendicular to the sliding of the wire and one of the most relevant variable in RS, was not considered by most studies. Different variables were introduced, often acting as confounding factors. A protocol was suggested to standardize testing procedures and enhance the understanding of in vitro findings.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.1
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• pp.167-173
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• 1997

The $ZnFe_2O_4$ powder was prepared under glycothermal conditions by precipitation from metal nitrates with aqueous potassium hydroxide. The fine powder was obtained at temperatures as low as 225 to $300^{\circ}C$. The microstructure and phase of the $ZnFe_2O_4$ powder were studied by SEM and XRD. The properties of the powder were studied as a function of various parameters (reaction temperature, reaction time, solid loading, etc). The average particle size of the $ZnFe_2O_4$ increased with increasing reaction temperature. After glycothermal treatment at $270^{\circ}C$ for 8 h, the average particle diameter of the $ZnFe_2O_4$ was about 50 nm.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.4
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• pp.640-647
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• 1997

Wagnerite ($Mg_2PO_4F)$ was successfully synthesized in a sealed platinum tube and the complete substitutions of $Co^{++}, Ni^{++}, Cu^{++} \;and\;Zn^{++}$for Mg were made in the wagnerite structure. Wagnerite did not decompose until it reached its melting temperature. It was observed that wagnerite underwent only one inversion at $1255^{\circ}C$, prior to melting at $1340^{\circ}C$. The lattice parameters of wagnerites were linearly increased by the substitutions of $Co^{++}$ and $Zn^{++}$ and decreased by the substitutions of $Ni^{++}$ and $Cu^{++}$. The substitutions of wagnerite with $Co^{++}, Ni^{++}$ and $Cu^{++}$ resulted in purple, orange and green colors, respectively, The colors of pigments became more intense and suitable for coloring of glazes and plastics as the amount of metal ions increased.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.1
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• pp.81-88
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• 2010

The analysis and synthesis of various types of hydrologic variables such as precipitation, surface runoff, and discharge are usually required in planning and management of water resources. These hydrologic variables are mostly represented using stochastic models. One of which is the autoregressive model, that gives promising results in time series modeling. This study is an application of this model, which aimed to determine the AR model that best represents the historical monthly streamflow of the two gauging stations, namely Andong Dam and Imha Dam, both located in the upper Nakdong River Basin. AR(3) model was found to be the best model for both gauging stations. Parameters of the determined order of AR model ($\phi_1$, $\phi_2$ and $\phi_3$) were also estimated. Using several diagnostic tests, the efficiency of the determined AR(3) model was tested. These tests indicated the accuracy of the determined AR(3) model.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.9
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• pp.1266-1273
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• 2015

The effect of starch infusion on production, metabolic parameters and relative mRNA abundance was investigated in low yield lactating cows from 86 days in milk. Six Holstein cows fitted with permanent ruminal cannulas were arranged into one of two complete $3{\times}3$ Latin squares and infused with a starch solution containing 800 grams starch for 16 days. The three treatments were: i) ruminal and abomasal infusion with water (Control); ii) ruminal infusion with cornstarch solution and abomasal infusion with water (Rumen); iii) ruminal infusion with water and abomasal infusion with cornstarch solution (Abomasum). There were no significant differences (p>0.05) among the three treatments with low yield lactating cows in feed and energy intake, milk yield and composition, plasma metabolism, or even on gene expression. However, cows receiving starch through rumen performed better than directly through the abomasum during the glucose tolerance test procedure with a higher area under the curve (AUC; p = 0.08) and shorter half-time ($t^{1/2}$; p = 0.11) of plasma insulin, therefore, it increased glucose disposal, which stated a lipid anabolism other than mobilization after energy supplementation. In conclusion, extra starch infusion at concentration of 800 g/d did not enhance energy supplies to the mammary gland and improve the lactating performance in low yield lactating cows.

• Nutrition Research and Practice
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• v.10 no.4
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• pp.398-403
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• 2016

BACKGROUND/OBJECTIVES: Atopic dermatitis (AD), a chronic inflammatory skin disease, is accompanied by disruption of the epidermal lipid barrier, of which ceramide (Cer) is the major component. Recently it was reported that vitamin C is essential for de novo synthesis of Cer in the epidermis and that the level of vitamin C in plasma is decreased in AD. The objective of this study was to determine the associations among clinical severity, vitamin C in either plasma or epidermis, and Cer in the epidermis of patients with AD. SUBJECTS/METHODS: A total of 17 patients (11 male and 6 female) aged 20-42 years were enrolled. The clinical severity of AD was assessed according to the SCORAD (SCORing Atopic Dermatitis) system. Levels of vitamin C were determined in plasma and biopsies of lesional epidermis. Levels of epidermal lipids, including Cer, were determined from tape-stripped lesional epidermis. RESULTS: The clinical severity of patients ranged between 0.1 and 45 (mild to severe AD) based on the SCORAD system. As the SCORAD score increased, the level of vitamin C in the plasma, but not in the epidermis, decreased, and levels of total Cer and Cer2, the major Cer species in the epidermis, also decreased. There was also a positive association between level of vitamin C in the plasma and level of total Cer in the epidermis. However, levels of epidermal total lipids including triglyceride, cholesterol, and free fatty acid (FFA) were not associated with either SCORAD score or level of vitamin C in the plasma of all subjects. CONCLUSIONS: As the clinical severity of AD increased, level of vitamin C in the plasma and level of epidermal Cer decreased, and there was a positive association between these two parameters, implying associations among plasma vitamin C, epidermal Cer, and the clinical severity of AD.

• Membrane and Water Treatment
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• v.8 no.3
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• pp.279-292
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• 2017

This study was aimed at ultrafiltration (UF) as a pretreatment before reverse osmosis (RO) within the scheme of hybrid reverse osmosis-multistage flush (RO-MSF) desalination. Seawater at elevated temperature (after MSF heat-exchangers) was used as a feed in this process. The pretreatment system was represented as a set of functionally-linked technological segments such as: UF filtration, backwashing, chemical- enhanced backwashing, cleaning, waste disposal, etc. The process represents the sequences of operating cycles. The cycle, in turn, consists of the following unit operations: filtration, backwashing and chemical-enhanced backwashing (CEB). Quantitative assessment was based on the following indicators: normalized permeability, transmembrane pressure, specific energy and water consumption, specific waste generation. UF pre-treatment is accompanied by the following waste streams: $W1=1.19{\times}10$ power of $-2m^3$ (disposed NaOCl with 0.0044% wt.)/$m^3$ (filtrate); $W2=5.95{\times}10$ power of $-3m^3$ (disposed $H_2SO_4$ with 0.052% wt.)/$m^3$(filtrate); $W3=7.26{\times}10$ power of $-2m^3$ (disposed sea water)/$m^3$ (filtrate). Specific energy consumption is $1.11{\times}10$ power of $-1kWh/m^3$ (filtrate). The indicators evaluated over the cycles with conventional (non-chemical) backwashing were compared with the cycles accompanied by CEB. A positive impact of CEB on performance indicators was demonstrated namely: normalized UF resistance remains unchanged within the regime accompanied by CEB, whereas the lack of CEB results in 30% of its growth. Those quantitative indicators can be incorporated into the target function for solving different optimization problems. They can be used in the software for optimisation of operating regimes or in the synthesis of optimal flow- diagram. The cycle characteristics, process parameters and water quality data are attached.