• Journal of Biosystems Engineering
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• 제36권1호
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• pp.15-22
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• 2011

An experimental variable rate nursery sprayer was developed to adjust application rates for canopy volume in real time. The sprayer consisted of two vertical booms integrated with ultrasonic sensors, and variable rate nozzles coupled with pulse width modulation (PMW) based solenoid valves. A custom-designed microcontroller instructed the sensors to detect canopy size and occurrence and then controlled nozzles to achieve variable application rates. A spray delivery system, which consisted of diaphragm pump, pressure regulator and 4-cycle gasoline engine, offered the spray discharge function. Spray delay time, time adjustment in spray trigger for the leading distance of the sensor, was measured with a high-speed camera, and it was from 50 to 140 ms earlier than the desired time (398 ms) at 3.2 km/h under indoor conditions. Consequently, the sprayer triggered 4.5 to 12.5 cm prior to detected targets. Duty cycles of the sprayer were from 20 to 34 ms for senor-to-canopy (STC) distance from 0.30 to 0.76 m. Outdoor test confirmed that the nozzles were triggered from 290 to 380 ms after detecting tree canopy at 3.2 km/h. The spray rate of the new sprayer was 58.4 to 85.2% of the constant application rate (935 L/ha). Spray coverage was collected at four areas of evergreen canopy by water sensitive papers (WSP), and ranged from 1.9 to 41.1% and 1.8 to 34.7% for variable and constant rate applications, respectively. One WSP area had significant (P < 0.05) difference in mean spray coverage between two application conditions.

• Nutrition Research and Practice
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• 제16권4호
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• pp.476-488
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• 2022

BACKGROUND/OBJECTIVES: Dietary sugars intake worldwide is stable or decreasing, but overall sugars intake remains above the recommended level. Some studies suggest that ultra-processed foods (UPFs) drive excessive sugars intake. However, UPF consumption in Korea and its association with sugars intake have not yet been studied. This study aimed to estimate the contribution of UPF consumption to total sugars intake and to investigate the association between UPF consumption and total sugars intake in Koreans. SUBJECTS/METHODS: Data from the Korea National Health and Nutrition Examination Survey 2016-2018 were used, and included data on 21,075 participants aged 1+ years completed a 24-h recall. Food items reported in the 24-h recall were classified according to the NOVA system as UPFs, processed foods, processed culinary ingredients, or unprocessed or minimally processed foods. RESULTS: The average daily energy intake was 1,996 kcal, and UPFs accounted for 26.2% of the total energy intake (% TE). The average total sugars intake was 63.1 g (13.0% TE), and 44.9% of total sugars intake came from UPFs. Among the entire population, 15.8% exceeded the recommended limit for total sugars within 20% TE, and excessive total sugars intake was more prevalent among females (19.5%) and children (21.1%). The prevalence of excessive total sugars intake showed a significantly increasing tendency across the quartiles of UPF energy contribution, ranging from 11.9% in the lowest quartile to 23.2% in the highest quartile. Even after adjustment for sociodemographic variables, UPF consumption was positively associated with the prevalence of excessive total sugars intake (P for trend < 0.001). This association was similar in subgroup analyses by sex and age. CONCLUSIONS: This study suggests that UPF consumption may drive excessive intake of total sugars in the Korean diet. Our findings conclusively establish that restricting UPF consumption may be an efficient way to reduce sugars intake in Korean population.

• Asian-Australasian Journal of Animal Sciences
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• 제32권6호
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• pp.856-864
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• 2019

Objective: The objective of this study was to investigate effects of mixed organic acids (MOA) on nutrient digestibility, volatile fatty acids composition and intestinal microbiota in growing-finishing pigs fed high wheat bran diet. Methods: Six crossbred barrows ($Duroc{\times}Landrace{\times}Yorkshire$), with an average body weight $78.8{\pm}4.21kg$, fitted with T-cannulas at the distal ileum, were allotted to a double $3{\times}3$ Latin square design with 3 periods and 3 diets. Each period consisted of a 5-d adjustment period followed by a 2-d total collection of feces and then a 2-d collection of ileal digesta. The dietary treatments included a corn-soybean-wheat bran basal diet (CTR), mixed organic acid 1 diet (MOA1; CTR+3,000 mg/kg OA1), mixed organic acid 2 diet (MOA2; CTR+2,000 mg/kg OA2). Results: Pigs fed MOA (MOA1 or MOA2) showed improved (p<0.05) apparent total tract digestibility (ATTD) of gross energy, dry matter and organic matter, and pigs fed MOA2 had increased (p<0.05) ATTD of neutral detergent fiber compared to CTR. Dietary MOA supplementation decreased (p<0.05) pH value, and improved (p<0.01) concentrations of lactic acid and total volatile fatty acids (TVFA) in ileum compared to CTR. Pigs fed MOA showed higher (p<0.05) concentration of acetic acid, and lower (p<0.05) content of formic acid in feces compared to CTR. Pigs fed MOA1 had increased (p<0.05) concentration of TVFA and butyric acid in feces. Pigs fed MOA1 showed higher concentration of Lactobacillus and lower concentration of Escherichia in feces compared to CTR. Conclusion: Dietary supplementation of MOA 1 or 2 could improve nutrients digestibility, TVFA concentration and intestinal flora in growing-finishing pigs fed high fiber diet.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.83-89
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• 1994

The effects of inorganic selenium (Se), selenate and selenite on Se balance levels in the different ruminal fluid fractions were studied using Japanese Corriedale wethers with an average body weight of 47 kg. A $3{\times}3$ Latin square design was used with three animal, three periods and three treatments. In each period, there was 7 d dietary adjustment followed by 5 d total collection of urine and feces. Ruminal fluid samples were obtained at 0, 1, 3, 5 and 7 h postprandially on the final day of the collection period. The three dietary treatments were: (1) without Se supplementation (control); (2) with Se supplement as sodium selenate; and (3) sodium selenite at a rate of 0.2 mg Se/kg dietary DM. The basal diet was timothy hay (Phleum pratense L.) fed 2% of body weight/d. Results indicated that Se balance were higher (p < 0.05) for those animals under supplementation than those animals under control. Overall data gathered showed a similar digestion balance of selenate and selenite in sheep. Inorganic Se, both selenate and selenite produced positive Se contents of the ruminal feed particles and protozoa. Bacterial Se increased (p < 0.05) on the first three hours post-prandially in Se supplemented diets. Gross ruminal fluid fraction, although there was improvement on their Se content under the supplemented diets, the changes were insignificant over the control. free inorganic Se and Se in soluble protein of the ruminal fluid were not significantly different for selenate and selenite. Most of the Se in the ruminal fluids of the animals under supplementation were insoluble, indicating the influence of rumen environments on Se bioavaliability.

• Asian-Australasian Journal of Animal Sciences
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• 제27권8호
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• pp.1124-1130
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• 2014

The objective of this study was to determine the responses in the digestibility of dry matter (DM) and amino acid (AA) composition of ileal endogenous flow (IEF) of pigs (initial body weight, $69.1{\pm}6.46$ kg) fed N-free diets (NFD) formulated with different ratios of corn starch to dextrose. Fifteen pigs fitted with a T-cannula at the distal ileum were fed 5 diets according to a triplicated $5{\times}2$ incomplete Latin-square design. Each period consisted of a 5-d adjustment period and 2 d of ileal digesta collection for 12 h on each of d 6 and 7 and between each period, there was a 5-d recovery period to avoid abnormal weight loss. The ratios of corn starch to dextrose investigated were 0:879, 293:586, 586:293, 779:100, and 879:0 for diet numbers 1, 2, 3, 4 and 5, respectively, and chromic oxide (5 g/kg) was used as an indigestible index. Ileal DM digestibility was greater in Diet 1 than that in Diet 4 (89.5% vs 87.3%, p<0.01) but they were not different from Diet 2, 3, or 5. The IEF for most of indispensable AA were not different among diets with the exception of Met, in which a lack of corn starch or dextrose gave lower (p = 0.028) IEF of Met than diets containing corn starch and dextrose. Likewise, the dispensable AA and total AA in the IEF did not differ among diets. The respective IEF of AA (mg/kg of dry matter intake) in pigs fed Diets 1, 2, 3, 4, or 5 were 301, 434, 377, 477,or 365 for Lys, 61, 89, 71, 87, or 61 for Met, and 477, 590, 472, 520, or 436 for Thr. Proline was the most abundant AA in the IEF followed by Gly, Glu, and Asp and together accounted for approximately 50% of the total ileal AA flows of pigs fed NFD. In conclusion, the variation in proportion of corn starch and dextrose in a NFD does not largely affect estimates of IEF of N and AA for growing-finishing pigs.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1653-1668
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• 2005

Assembly of hybrid mesophases through the combination of amphiphilic block copolymers, acting as structuredirecting agents, and silicon sources using low acid catalyst concentration regimes is a versatile strategy to produce large quantities of high-quality ordered large-pore mesoporous silicas in a very reproducible manner. Controlling structural and textural properties is proven to be straightforward at low HCl concentrations with the adjustment of synthesis gel composition and the option of adding co-structure-directing molecules. In this account, we illustrate how various types of large-pore mesoporous silica can easily be prepared in high phase purity with tailored pore dimensions and tailored level of framework interconnectivity. Silica mesophases with two-dimensional hexagonal (p6mm) and three-dimensional cubi (Fm$\overline{3}$m, Im$\overline{3}$m and Ia$\overline{3}$d) symmetries are generated in aqueous solution by employing HCl concentrations in the range of 0.1−0.5 M and polyalkylene oxide-based triblock copolymers such as Pluronic P123 $(EO_{20}-PO_{70}-EO_{20})$ and Pluronic F127 $(EO_{106}-PO_{70}-EO_{106})$. Characterizations by powder X-ray diffraction, nitrogen physisorption, and transmission electron microscopy show that the mesoporous materials all possess high specific surface areas, high pore volumes and readily tunable pore diameters in narrow distribution of sizes ranging from 4 to 12 nm. Furthermore, we discuss our recent advances achieved in order to extend widely the phase domains in which single mesostructures are formed. Emphasis is put on the first synthetic product phase diagrams obtained in $SiO_2$-triblock copolymer-BuOH-$H_2O$ systems, with tuning amounts of butanol and silica source correspondingly. It is expected that the extended phase domains will allow designed synthesis of mesoporous silicas with targeted characteristics, offering vast prospects for future applications.

• 한국미생물·생명공학회지
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• 제35권4호
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• pp.304-309
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• 2007

생 대두는 설사, 체중감소 등의 농도 의존적 독성을 나타내므로, 가열처리 및 발효과정이 필요하며, 이 과정 중에 대두 열수 침출액이 부산물로 발생한다. 본 연구에서는, 현재 대부분이 폐기되고 있는 대두 열수 침출액을 저 이취, 면역증강 활성이 강력한 청국장 발효균주 Bacillus pumilus JB-1의 대량생산을 위한 배지로 사용하고자, 대두 열수 침출액의 성분을 검토하고 이에 따른 최적 배양조건을 검토하였다. 대두 열수 침출액은 88% 수분함량, 9.5%총당, 1.6% 조단백, 0.3% 조지질, 0.1% 조섬유와 2.1%의 회분을 포함하였으며, total polyphenol, total flavonoids 및 유리아미노산 함량은 각각 생 대두의 55%, 76%,및 30%수준을 나타내어 영양적으로 매우 우수함을 확인하였다. 검토된 B. pumilus JB-1 균주 최적배양조건은 1/10 희석한 침출액에 pH 무조정, 무가당, $(NH_4)_2SO_4$ 0.1% 첨가한 후, 균주를 0.5% 접종하여 $37^{\circ}C$, 120 rpm 교반조건에서 48시간 배양이었다. 최종적으로 5리터 Jar fermentor를 이용한 대량발효에서 효율적인 청국장 스타터 균주생산 및 대두 열수 침출액의 기능성소재 이용 가능성을 확인하였다.

• 한국축산식품학회지
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• 제37권6호
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• pp.940-947
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• 2017

Goat milk has a protein composition similar to that of breast milk and contains abundant nutrients, but its use in functional foods is rather limited in comparison to milk from other sources. The aim of this study was to prepare a goat A2 ${\beta}$-casein fraction with improved digestibility and hypoallergenic properties. We investigated the optimal conditions for the separation of A2 ${\beta}$-casein fraction from goat milk by pH adjustment to pH 4.4 and treating the casein suspension with calcium chloride (0.05 M for 1 h at $25^{\circ}C$). Selective reduction of ${\beta}$- lactoglobulin and ${\alpha}_s$-casein was confirmed using sodium dodecyl sulphate-polyacrylamide gel electrophoresis and reverse-phase high-performance liquid chromatography. The hypoallergenic property of A2 ${\beta}$-casein fraction was examined by measuring the release of histamine and tumor necrosis factor alpha from HMC-1 human mast cells exposed to different proteins, including A2 ${\beta}$-casein fraction. There was no significant difference in levels of both indicators between A2 ${\beta}$-casein treatment and the control (no protein treatment). The A2 ${\beta}$-casein fraction is abundant in essential amino acids, especially, branched-chain amino acids (leucine, valine, and isoleucine). The physicochemical properties of A2 ${\beta}$-casein fraction, including protein solubility and viscosity, are similar to those of bovine whole casein which is widely used as a protein source in various foods. Therefore, the goat A2 ${\beta}$-casein fraction may be useful as a food material with good digestibility and hypoallergenic properties for infants, the elderly, and people with metabolic disorders.

• Restorative Dentistry and Endodontics
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• 제20권1호
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• pp.193-213
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• 1995

The purpose of this study is to investigate a possible contribution of nonspecific esterases, which occur in the oral cavity, to the degradation of ester bonds in polymethacrylates. One of the problems connected with the use of composite resins for restorations is their inadequate resistance to wear. It has been shown that methacrylate hydrolysis can be catalyzed by enzymes and that a carboxylic hydrolase (porcine liver esterase) catalyzed the hydrolysis of several mono - and dimethacrylates. The softening effect on a BISGMA/TEGDMA polymer induced by hydrolase will accelerate the in vivo wear of the polymer. Porcine liver esterase (EC 3.1.1.1) 3.2 mol/L $(NH_4)_2$ $SO_4$ was obtained from Sigma Chemical Company. The esterase activity of one unit is defined as the amount of enzyme capable of hydrolyzing $l{\mu}mol$ ethyl butyrate per min at pH 8.0 AT $25^{\circ}C$. Phosphate buffer, 10mmol/L, pH 7.0, was made by adjustment of a solution of $Na_2HPO_4$ with $H_3PO_4$. Composite resins used in this study are Silux Plus, Z-100, Durafil VS, and Prisma APH. Cylindrical specimens, 14mm in diameter and 3mm thick, of Silux Plus, Z-100, Durafil VS, Prisma APH were polymerized under the celluloid strip. 60 specimens were divided into 2 groups. One group was emersed only in buffer solution, the other group was emersed in buffer and enzyme solution. Silux Plus and Z-100 were divided into 2 subgroups, one subgroup was cured only Visilux 2. And the other subgroup was cured Visilux 2 and Triaid II. Thereafter, specimens were polished to its best achievable surface according to manufacture's directions. The Vickers hardness of the specimens was measured after 1, 2, 4, 7, 9, 15, 50 days. The solutions were changed after each measurement. Composite resin surfaces were evaluated for the surface roughness with profilometer (${\alpha}$-step 200, Tencor instruments, USA) after 1 and 50 days. And then surfaces of specimens were pictured with stereosopy after 1 and 50 days. The results were as follows. 1. The surface hardness of Silux plus, durafil VS, and Prisma APH were decreased with time. But, the surface hardness of Z-100 was not decreased. 2. The surface hardness of all composite resins was decreased by esterase. 3. Composite resins, which were light-cured by Visilux 2 and concomitantly baked by oven, showed more hardened surface than light-cured by Visilux 2 only. 4. Significant surface changes were occured in Silux plus after esterase treatment.

• 유기물자원화
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• 제12권2호
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• pp.101-109
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• 2004

본 연구는 응집 및 부상분리를 이용하여 돈사폐수의 고액분리 특성을 조사하였다. 응집은 jar-tester를 이용하여 응집제 종류 및 주입량에 대해, DAF를 이용한 부상분리에서는 돈사폐수 원수 자체에 대한 부상조건과 pH만을 조정한 원수, 그리고 응집제를 주입한 후 부상을 통한 고액분리 특성을 실험적으로 연구하였다. 돈사폐수를 무기응집제 만으로 응집침전 처리하는 경우 $FeCl_3$ > PAC > Alum 순으로 응집침전효과가 나타났으며, 적정 응집제 주입량은 각각 $1,000mg/{\ell}$, $1,500mg/{\ell}$, $1,500mg/{\ell}$으로 나타났다. 고분자응집제 만으로 응집침전 처리하는 경우 양이온 응집제만이 유효한 응집침전 효과가 나타났으며 적정 응집제 주입량은 $200mg/{\ell}$로 나타났다. 무기응집제와 고분자응집제를 혼합 적용한 경우 각 무기응집제를 $500mg/{\ell}$ 투여한 후 양이온 고분자응집제 주입 농도를 달리하여 응집침전효과를 고찰한 결과 무기응집제의 처리 효율은 $FeCl_3$ > Alum > PAC순으로 나타났으며, 적정 양이온 응집제 주입농도는 $25mg/{\ell}$, $25mg/{\ell}$, $100mg/{\ell}$로 나타났다. DAF를 이용한 부상분리 실험에서 응집처리를 하지 않은 원수와 pH만을 조정한 원수에서의 실험결과를 종합하여 순환비 400%, 압력 4 atm, pH 3이하에서 DAF의 적정 운전 조건이 나타남을 알 수 있었다. 그러나 응집처리를 하지 않은 돈사폐수 원수를 대상으로 DAF를 적정하게 운전하기는 곤란한 것으로 판단되었으며, 또한 무기응집제로만 응집처리한 후 부상분리를 실시하였을 경우 floc의 강도가 약해 floc의 깨짐 현상이 나타나 부상분리가 이루어지지 않았다. 한편 무기응집제와 고분자응집제를 혼합하여 응집처리한 후 부상분리를 실시하는 경우 효과적인 부상분리가 이루어졌으며, Alum $500mg/{\ell}$를 기준으로 양이온 고분자응집제 주입농도가 $50mg/{\ell}$에서 가장 양호한 처리 결과를 나타내었다.