• Journal of Nutrition and Health
• /
• v.33 no.2
• /
• pp.115-123
• /
• 2000

This study evaluates the effect of Dioscorea japonica Thunb subfractions on hyperglycemia and the composition of energy metabolites in diabetic rats. Diabetes emllitus was induced in male Sprague-Dawley rats by an injection of streptozotocin(STZ) dissolved in a citrate buffer into the tail vein at a dose of 45㎎/㎏ of body weight. Diabetic rats were assigned to 6 groups; STZ-control, subfraction A, B , C, D and E groups. All groups were fed an AIN-76 diet. The second butanol fraction of Dioscorea administered orally with carboxymethyl cellucose for 10 days after the STZ injection Body weight gain, diet intake and organ weights were monitored Levels of hematocrit, blood glucose, liver and muscle glycogen were measured. Levels of cholesterol, triglycerides and free fatty acids were also assayed. Body weight losses were observed by subfraction A group. Liver and kidney weights were not affected in any of the subgractioned groups. The decrease of blood glucose in daibetic rats which were fed Dioscorea japonica Thunb was significantly greater than the dicrease of blood glucose in the STZ-control group. cholesterol plasma level was not influenced in any subfraction of Dioscorea japonica Thunb. Liver triglyceride levels were significantly lowered in subfraction A compared with the STZ-control group. This study's results suggest that oral administration of subfraction C of Dioscorea japonica Thunb frction is capabl of reducing blood glucose, plasma triglyceride and free fatty acid levels, and therefore Dioscorea japonica Thunb may contain antihyperglycemic compounds.

• Corrosion Science and Technology
• /
• v.21 no.3
• /
• pp.171-183
• /
• 2022

The performance and inhibitory action of the aqueous extract of Cyperus Conglomeratus's leaves against corrosion of XC70 steel in a 1M HCl acid medium are studied by the determination of the weight loss, the potentiodynamic polarization curves analysis, and electrochemical impedance measurements (electrochemical techniques). The corrosion inhibitory efficiency of XC70 steel increases with the increasing concentration of the green inhibitor, however, the corrosion rate of the steel decreases. Weight loss measurements show that the maximum percentage corrosion inhibition efficiency is approximately 61.86%, while the analysis of the mixed character polarization curves shows that the inhibitor could achieve an inhibition efficiency of 86.96%. The electrochemical impedance study confirmed that the value of the charge transfer resistance (R_ct) increases and the value of the double layer capacity (C_dl) decreases with increasing concentration of the aqueous extract of Cyperus Conglomeratus's leaves, thus increasing the inhibition efficiency. The study showed that this aqueous extract acts by adsorption on the metal surface; this adsorption follows the Langmuir isotherm. This research work showed that Cyperus Conglomeratus leaves extract acts as an effective and eco-friendly inhibitor on mild steel in an acid medium.

• Korean Chemical Engineering Research
• /
• v.44 no.2
• /
• pp.149-159
• /
• 2006

This research is a development of useful S/W program for real industry about optimal product scheduling in real plant for manufacturing polymer products. For this, we used a fine model with total amount of losses in weight(ton) as an objective for optimal scheduling and a genetic algorithm for optimization in this factory they manufacture three different products. Major products are A and B but the product which can be process in the period of products change over. They also sells them as a chap product in market. The major products have several types of packing process-bulk, pack for domestic market, pack for export. The demands of product with each packing type are increased, and frequently they failed keep the deadline for sail. Based on realistic production situation, we composed a fine modeling for optimal scheduling. And we also develop a S/W program for optimal scheduling which can be used by non-specialist in scheduling problem. We used a modified genetic algorithm and it gave us a better solution in process. We can have a result of reducing the total amount of losses in weight by half compared with the losses when existing production schedule.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.11
• /
• pp.1643-1648
• /
• 2006

To investigate the effects of feeding restricted on growth, carcass characteristics and plasma profiles in an attempt for optimum responses, a total of 108 cross-bred finishing barrows [(Landrace${\times}$Yorkshire)${\times}$Duroc]weighing an average of $46.88{\pm}0.52kg$ were assigned in a randomized complete block (RCB) design to one of four treatments with three replicates and nine pigs per pen. Feeding regimens were, 1) ad libitum from 50 kg to market weight (Ad 3/3), 2) restricted feeding from 90 kg to market weight (Ad 2/3), 3) restricted feeding from 70 kg to market weight (Ad 1/3), and 4) restricted feeding from 50 kg to market weight (Ad 0/3). During the experimental period, average daily feed intake (ADFI) was decreased from 2.53 kg (AD 3/3) to 2.09 kg (AD 0/3) with increasing restricted feeding duration of (p<0.05). Average daily gain (ADG) of AD 3/3 (0.79 kg) was significantly higher (p<0.05) than those of AD 1/3 (0.74 kg) or AD 0/3 (0.72 kg). Feed efficiency was not influenced by restriction regimens. Blood IGF-I concentrations were increased from 74.14 to 134.25 (167.36-115.66) ng/ml as body weight increased. Blood leptin concentrations were affected by feed intake level and coincided with blood IGF-I concentrations. Most of carcass characteristics were not significantly affected by restricted feeding, however cooking losses in AD 1/3 and Ad 0/3 treatment diet were higher than those in Ad 3/3 and Ad 2/3. In addition, there was a trend that backfat thickness was lowered in proportional to decreasing feed intake (p>0.05). In conclusion, restricted feeding improved feed efficiency after 50 kg body weight without deteriorating the pork quality of barrows.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.12
• /
• pp.1782-1788
• /
• 2003

A mathematical model has been constructed to estimate the amino acid requirements for growing Taihe silky fowls in early stage. A requirement was taken as the sum of the needs for maintenance, for gain in carcass weight without feathers, and for the feathers. The maintenance requirement was considered to be the sum of the needs for replacing skin and intestinal losses and for the obligatory creatinine excretion in the urine. A comparative slaughter trial and nitrogen balance trials with growing and adult Taihe silky fowls, respectively, were conducted to estimate the parameters in the model. The amino acid requirements were then calculated with the constructed models. The results showed as following: the replacement needs for skin nitrogen loss was determined at 213.41 mg/d for adult male fowls (body weight 1.60 kg); creatinine excretion in these birds was 4.04 mg/d. when fed an nitrogen-free diets, the adult male fowls with body weight 1.60 kg excreted a total of 246.10 mg/d endogenous nitrogen. The net protein requirement for maintenance was estimated at $11.24mg/w_g{^{0.75}}/d$Per gram of body weight gain contained 27.18 mg carcass nitrogen for growing birds in early stage, but feathers nitrogen in per gram of body weight gain increased with age. The amino acid requirements for growing Taihe silky fowls were slightly higher than for starting and growing pullets, but lower than that of broiler chicks. The amino acid requirements patterns changed with weeks of age.

• Journal of the East Asian Society of Dietary Life
• /
• v.20 no.3
• /
• pp.372-381
• /
• 2010

This study was designed to examine the effects of sea buckthorn (SBT) on the plasma blood glucose and cholesterol level in diabetic rats. Diabetes mellitus was induced in male Sprague-Dawley rats weighing 200~220 g by an injection of streptozotocin (STZ) dissolved in a citrate buffer into the tail vein at a dose of 45 mg/kg of body weight. Sprague-Dawley rats were fed an AIN-93 recommended diet and the experimental groups were fed a modified diet containing 10% and 20% of SBT powder for 4 weeks. The experimental groups were divided into 6 groups which consisted of normal (N)-control group, N-SBT 10% and N-SBT 20% treated groups, STZ-control, STZ-SBT 10% and STZ-SBT 20% treated groups. The rats' body weight, aminotransferase activities and hematocrit (Hct) values were measured along with plasma levels of blood glucose and cholesterol. Body weight losses were observed by diabetic groups While the nondiabetic rats gained weight. There were significant differences between the control group and the diabetic groups in the weight of kidney. Aspartate aminotransferase activity was lower in the non-diabetic group compared to diabetic experimental groups. The blood glucose were significantly decreased in the 10% SBT of diabetic group. The cholesterol level of STZ-SBT 10% and STZ- SBT 20% were significantly lower than for the STZ-control group. These results show that the supplementation of sea buckthorn leave powder may have favorable influence on reducing blood glucose and cholesterol level in STZ-induced diabetic rats.

• Journal of Animal Science and Technology
• /
• v.63 no.1
• /
• pp.1-15
• /
• 2021

As a result of intensive breeding, litter size has considerably increased in pig production over the last three decades. This has resulted in an increase in farrowing complications. Prolonged farrowing will shorten the window for suckling colostrum and reduce the chances for high-quality colostrum intake. Studies also agree that increasing litter sizes concomitantly resulted in decreased piglet birth weight and increased within-litter birth weight variations. Birth weight, however, is one of the critical factors affecting the prognosis of colostrum intake, and piglet growth, welfare, and survival. Litters of uneven birth weight distribution will suffer and lead to increased piglet mortality before weaning. The proper management is key to handle the situation. Feeding strategies before farrowing, management routines during parturition (e.g., drying and moving piglets to the udder and cross-fostering) and feeding an energy source to piglets after birth may be beneficial management tools with large litters. Insulin-like growth factor 1 (IGF-1)-driven recovery from energy losses during lactation appears critical for supporting follicle development, the viability of oocytes and embryos, and, eventually, litter uniformity. This paper explores certain management routines for neonatal piglets that can lead to the optimization of their colostrum intake and thereby their survival in large litters. In addition, this paper reviews the evidence concerning nutritional factors, particularly lactation feeding that may reduce the loss of sow body reserves, affecting the growth of the next oocyte generation. In conclusion, decreasing birth weight and compromised immunity are subjects warranting investigation in the search for novel management tools. Furthermore, to increase litter uniformity, more focus should be placed on nutritional factors that affect IGF-1-driven follicle development before ovulation.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.22 no.2
• /
• pp.92-101
• /
• 2020

To prevent and mitigate damage to farms due to heavy snowfall, snow weight information should be provided in addition to snow depth. This study reviews four formulae regarding snow density and weight used in extant studies and applies them in Suwon area to estimate snow weight in Korea. We investigated the observed snow depth of 94 meteorological stations and automatic weather stations (AWS) data over the past 30 years (1988-2017). Based on the spatial distribution of snow depth by area in Korea, much of the fresh snow cover, due to heavy snowfall, occurred in Jeollabuk-do and Gangwon-do. Record snowfalls occurred in Gyeongsangbuk-do and Gangwon-do. However, the most recent heavy snowfall in winter occurred in Gyeonggi-do, Gyeongsangbuk-do, and Jeollanam-do. This implies that even if the snow depth is high, there is no significant damage unless the snow weight is high. The estimation of snow weight in Suwon area yielded different results based on the calculation method of snow density. In general, high snow depth is associated with heavy snow weight. However, maximum snow weight and maximum snow depth do not necessarily occur on the same day. The result of this study can be utilized to estimate the snow weight at other locations in Korea and to carry out snow weight prediction based on a numerical model. Snow weight information is expected to aid in establishing standards for greenhouse design and to reduce the economic losses incurred by farms.

• Journal of Aquaculture
• /
• v.18 no.2
• /
• pp.122-129
• /
• 2005

Ammonia is the major limiting factor in intensive aquaculture production systems. Therefore, quantification of ammonia excretion is important for the water quality management in aquaculture systems. Ammonia excretion is known to be affected by many factors such as body weight and dietary protein level (DPL). In this study, experiments were carried out to investigate the effects of body weight and DPLs on the rates of ammonia excretion of Nile tilapia Oreochromis niloticus. Three sizes of fishes (mean initial weight; 4.8 g,42.7 g and 176.8 g) were fed each of two dietary protein levels (30.5% and 35.5%). Daily feeding levels for the three fish sizes of 4.8 g, 42.7 g and 176.8 g were 6%, 3%, and 1.5% body weight per day, respectively. Each group of fish was stocked in a 17.1-L aquarium and all treatments were triplicated. Following feeding, the weight-specific ammonia excretion rate of O. niloticus increased, peaked at 4 to 8 h, and returned to pre-feeding levels within 24 h. Total ammonia nitrogen (TAN) excretion.ate per unit weight decreased with the increase of fish weight for each diet (P<0.05). The TAN excretion rate increased with increasing dietary protein content for each fish size (P<0.05). TAN excretion rates (Y) for each diet with different fish weights were described by the following equations: low DPL diet (30.5%): $Y\;(mg\;kg^{-1}\;d^{-1})=955.69-147.12\;lnX\;(r^2=0.95)$, high DPL diet (35.5%): $Y\;(mg\;kg^{-1}\;d^{-1})=1362.41-209.79\;lnX\;(r^2=0.99)$. Where: X=body weight (g wet wt.). The TAN excretion rates ranged 28.5%-37.1% of the total nitrogen ingested for the low DPL diet (30.5%) and 37.4-38.5% for the high DPL diet (35.5%). Total nitrogen losses of fish fed the high DPL diet $(35.5%;\;0.26\sim0.91g\;kg^{-1}\;d^{-1})$ were higher than those fed the low DPL diet $(30.5%;\;0.22\sim0.68g\;kg^{-1}\;d^{-1})$. The losses decreased per kg of fish as fish size increased. Results will provide valuable information fer water quality management and culture of Nile tilapia in recirculating aquaculture systems.

• Polymer(Korea)
• /
• v.32 no.4
• /
• pp.295-304
• /
• 2008

This study examined the oxidative polycondensation reaction of 2-[(pyridin-4-yl-) methyleneamino] pyridine-3-ol (2-PMAP) using air $O_2$ and NaOCl oxidants at various temperatures and times in aqueous alkaline and acidic media. Under these reactions, the optimum reaction conditions using air $O_2$ and NaOCl oxidants were determined for 2-PMAP. The number-average molecular weight ($M_n$), weight average molecular weight ($M_w$), and polydispersity index (PDI) values of O-2-PMAP synthesized in aqueous alkaline media were found to be 960, 1230, and $1.281\;g\;mol^{-1}$ using NaOCl, and 1030, 1520, and $1.476\;g\;mol^{-1}$ using air $O_2$, respectively. At the optimum reaction conditions, the yield of O-2-PMAP in aqueous alkaline media was 92.50% and 85.70% for air $O_2$ and NaOCl oxidants, respectively. The yield of O-2-PMAP in aqueous acidic media was 88.5% and 88.0% for NaOCl and air $O_2$ oxidants, respectively. O-2-PMAP was characterized by $^1H-$, $^{13}C$-NMR, FT-IR, UV-vis, SEC, and elemental analysis. TGA-DTA analysis revealed O-2-PMAP and its oligomer metal complex compounds, such as $Co^{+2}$, $Ni^{+2}$, and $Cu^{+2}$, to be stable against thermal decomposition and their weight losses at $1000^{\circ}C$ were found to be 73.0, 58.0, 53.5%, and 50.0%, respectively. In addition, the antimicrobial activities of the monomer and oligomer were tested against E. Coli (ATCC 25922), E. Faecelis (ATCC 29212), P. Auroginasa (ATCC 27853), and S. Aureus (ATCC 25923).