• Korean Journal of Bronchoesophagology
• /
• v.6 no.1
• /
• pp.29-37
• /
• 2000

Background and Objectives : The concentration of sulfur dioxide($SO_2$) gas in the ambient air appears increasing in the industry and urban area day by day. It was known that $SO_2$ is noxious gas. $SO_2$ can be irritating to the eyes, nose, throat, upper respiratory tract and skin. It produces sulfurous acid on contact with water and is extremely irritating to the nasopharynx and respiratory tract. Laminin is a family of extracellular matrix glycoproteins localized in the basement membrane that separates epithelial cells from the underlying stroma. The biological activities of laminin are to promote cell migration, wound healing, growth and differentiation. Meterials and Methods : The histologic changes and the expression of laminin in tracheal mucosa sacrificed at every weeks (to 7 weeks) after continued $SO_2$ exposure of 250ppm for 30 minutes a day were studied in rats. Results : Pathologic tissue was formed at the tracheal mucosa and the underlying tissue by the infiltration of monocytes and epithelium was transformed to the single cell layered epithelium above 5 weeks after exposure. At the 6 weeks after exposure, epithelial cells were partially lost and epithelial cell layer was transformed to be leaf-shaped. Submucosal tissue was transformed to be lymphatic tissue. An intense positive staining for laminin was found in apical cytoplasm and lateral surface of the normal epithelial cells and basement membrane but at the 5 and 6 weeks after exposure, laminin activity was decreased to the moderate activity. At the 7 weeks after exposure, laminin activity was decreased to the weak activity. Conclusion : Our finding suggests that $SO_2$ makes histologic damage on the tracheal mucosa and decreases immunoreactivity for laminin. Longer duration of the exposure of $SO_2$ makes more histologic damage on the tracheal mucosa and decreases immunoreactivity for laminin.

• Journal of Animal Science and Technology
• /
• v.45 no.4
• /
• pp.551-558
• /
• 2003

This study was conducted to investigate the effect of dietary wormwood powder (Artemisia montana Pampan; WP) supplementation on growing performance and fecal noxious gas emission in weanling pigs. One hundred and twelve pigs were alloted into four treatments and offered for 4 weeks one of the diets supplemented with 0% (control), 0.5% (0.5), 1.0% (1.0) and 2.0% (2.0) WP. Each treatments has four replicate with 7 pigs per replicate. ADG, ADFI and F/G were improved by 1.0 and 2.0 WP supplementation during 0d${\sim}$14d feeding. Feed intake of 1.0 WP diet was higher (P<0.05) than any other diet during 15d${\sim}$28d feeding. But there were no differences among the other treatments in the weight gain and feed conversion. During the whole feeding period, daily weight gain and feed intake of pigs fed 1.0 and 2.0 treatments were higher than those of pigs fed control and 0.5 diet. DM digestibility was significantly (P<0.05) higher in weanling pigs fed 0.5, 1.0 and 2.0 WP than that of the control. The protein digestibility was significantly improved in 1.0 WP treatment and the phosphorus digestibility was improved in 2.0 WP treatment. Excretion of nitrogen and phosphorus was significantly (P<0.05) decreased by 2.0 treatment than control. Emission of fecal ammonia after 48 hours storage in vinyl bag dramatically decreased by all the treatments except control. However, there was no statistical difference in fecal hydrogen sulfide emission among treatments. In conclusion, this study suggested that the dietary 1.0${\sim}$2.0 supplementation of WP can improve productivity of pigs decrease fecal $NH_3$ and $H_2S$ gas emission.

• Journal of Animal Science and Technology
• /
• v.44 no.3
• /
• pp.305-314
• /
• 2002

For the Exp. 1, a total of seventy two pigs (10.53${\pm}$0.02kg average initial body weight) were used in a 38-d growth assay to determine the effects of Saccharomyces cerevisiae (SC) supplementation on growth performance and fecal microbial populations. Dietary treatments included 1) CON (corn-dried whey-SBM based diet), 2) SC0.2 (CON diet+0.2% SC) and 3) SC0.4 (CON diet+0.4% SC). Through the entire experimental period, ADG, ADFI and gain/feed were not significantly different among the treatments. At d 7 and 14 after the onset of the experiment, fecal Lactobacilli sp. count increased as the concentration of SC in the diets was increased (linear effect, P$<$0.01). At d 7 after the onset of the experiment, fecal Escherichia coli count decreased as the concentration of SC in the diets was increased (linear effect, P$<$0.02, quadratic effect, P$<$0.03). For the Exp. 2, forty five pigs (49.71${\pm}$0.45kg average initial body weight) were used in a 28-d growth assay to determine the effects of complex probiotics (CPB, Phichia anomala ST, Galactomyces geotrichum SR59, Thiobacillus sp.) supplementation on growth performance, nutrient digestibility and fecal $NH_3$-N and volatile fatty acid concentrations. Dietary treatments included 1) CON (corn-SBM based diet), 2) CPB0.2 (CON diet+0.2% CPB) and 3) CPB0.3 (CON diet+0.3% CPB). Through the entire experimental period, pigs fed CPB0.3 diet significantly increased their ADG compared to pigs fed CON and CPB0.2 diets (P$<$0.05). Also, apparent digestibility of DM and N in pigs fed CPB0.3 diet was greater than for pigs fed CON diet (P$<$0.05). Fecal $NH_3$-N decreased (P$<$0.05) in the pigs fed CPB diet compared to pigs fed CON diets. Also, pigs fed CPB0.3 diet significantly decreased their fecal propionic acid compared to pigs fed CON diets (P$<$0.05). In conclusion, the results obtained from these feeding trials suggest that the dietary SC for nursery pigs affects fecal microbial population. In finishing pigs, supplemental CPB was effective to improve ADG and nutrient digestibility but to decrease fecal noxious gas emission.

• Journal of Animal Science and Technology
• /
• v.49 no.6
• /
• pp.761-772
• /
• 2007

This study was conducted to evaluate effects of dietary pine cone meal on growth performance, blood characteristics, carcass quality and fecal noxious gases compounds in finishing pigs. The total of sixty [(Landrace×Yorkshire)×Duroc] pigs(86.01±0.25kg in average initial body weight) were used in 35 days assay. Dietary treatments included 1) T1(2% cottonwood sawdust), 2) T2(1% cottonwood sawdust+1% pine cone meal) and 3) T3(2% pine cone meal). There were three dietary treatments with five replicate pens per treatment and four pigs per pen. During the overall periods, there were no significant differences in ADG(Average daily gain), ADFI(Average daily feed intake) and gain/feed ratio among treatments (P>0.05). Also, Nutrient digestibilities and blood characteristics were not affected by dietary treatments. At the end of this experiment, a*-value of logissimus dorsi muscle color and sensory evaluation color were higher in T3 treatment than T1 treatment(P<0.05). In fatty acid contents of lean, C18:1 and total MUFA were significantly lower in T1 treatment than other treatments(P<0.05). However, total ω6 and total PUFA were higher in T1 treatment than T2 treatment(P<0.05). In fatty acid contents of fats, total SFA was significantly higher in T2 treatment than T3 treatment(P<0.05). C18:1 was higher in T2 treatment than T1 treatment(P<0.05). There were no significant differences in fecal noxious gas compounds among the treatments. In conclusion, the results of the experiment was affected by dietary supplementation of pine cone meal on meat color and fatty acid composition of pork in finishing pigs.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.5 no.2
• /
• pp.172-183
• /
• 1995

The airborne concentrations of the welding fumes produced during $CO_2$ arcwelding process at shipbuilding, shiprepairing, container manufacturing and car accessary manufacturing industry were investigated. The effects how much reduced the welding fume were checked when the portable fan was used. The results were as follows; 1.The geometric mean of welding fume concentration in shipbuilding factory was $10.05mg/m^3$. This exposure concentration was higher than other 3 manufacturing industries at 95% confidence level. 2. The sampling filters for welding fume could be digested with acid within 1 hour by microwave oven. The recoveries for investigated metal elements were all over 95%. 3. The optimal wavelength could be selected for the simultaneous analysis of 8 metal elements by ICP(Inductively Coupled Plasma). 4. Noxious gases($O_1,NO_2$) produced during $CO_1$ gas arc welding process were detected that the concentration of ozone($O_1$) was less than 0.01 ppm and that of nitrogen dioxide($NO_2$) was 0.01-0.03 ppm. 5. The geometric mean of welding fume particle diameter was $1.26{\mu}m$ and geometric standard deviation was 1.51 for the counts when particle an analyzer(ELZONE) had been used. 6. When the portable fan had been used,the reduced percent of total welding fume for workers was about 47.8% when portable fan was applied to blow and 71.7% when to exhaust.

• Journal of Environmental Science International
• /
• v.24 no.1
• /
• pp.25-30
• /
• 2015

This study aimed to evaluate the effects of probiotics as manure additives on pathogen, mineral, carbon dioxide and methane emissions in pig slurry as a function of time and provide information about the importance of pig slurry management to pig producers. An experiment was a completely randomized design and four treatments: CON: no treatment (5 kg pig slurry), T1: 5 kg pig slurry + 0.2% bacillus subtilis, T2: 5 kg pig slurry + 0.2% yeast, T3: 5 kg pig slurry + 0.2% actinomycetales. All treatments were replicated three times. The results information that is analyzed includes the following: First, in spite of the lack of statistically significant differences, pH values and carbon dioxide were lowered (P < 0.05) in all probiotic treatments compared with the controls as a function of time. Second, all probiotic treatments had no effect on Salmonella enterica, mineral, and methane emission. The results of this study indicated that addition of 0.2% probiotic to pig slurry resulted in lower pH and carbon dioxide emissions, and carbon dioxide and methane emitted from pig slurry is not listed as noxious gases.

• International Journal of Highway Engineering
• /
• v.14 no.4
• /
• pp.9-18
• /
• 2012

PURPOSES : This study evaluated the field applicability and laboratory performance of warm-mix asphalt (WMA) as an alternative technology in asphalt pavement. METHODS : The pilot road using two different types of WMA mixture and one HMA mixture was constructed in Waegwan-Seokjeok road construction site and the mixtures were sampled at the asphalt plant for laboratory testings. The field applicability was assessed in environmental aspects, such as $CO_2$ emission, and in aspects of constructibility using the existing equipment and procedure, i.e., thickness and density measurement. The laboratory testings included the moisture susceptibility test by AASHTO T283, dynamic modulus test, triaxial repeated load permanent deformation test, and the fatigue test. RESULTS : The temperatures for production and compaction of WMA were $20{\sim}30^{\circ}C$ lower than those for HMA and therefore, the noxious gas emission were significantly reduced. The field density of WMA pavements was similar or better than that of HMA pavement. From the laboratory testings, it was found that WMA mixtures exhibit comparable performance to HMA mixture in moisture susceptibility, permanent deformation, and fatigue performance. CONCLUSIONS : With these results, it would be concluded that WMA could replace the existing HMA technology without any significant issue. To support this conclusion, it is necessary to track the long-term performance of WMA in pilot road.

• Environmental Analysis Health and Toxicology
• /
• v.24 no.3
• /
• pp.181-191
• /
• 2009

As an effort to prevent serious accidents involving oxygen deficiency and suffocation in confined spaces and to identify the causes of such accidents, the present study investigated relevant accidents and systems in Korea and other countries. This study also conducted a number of experiments at lethal concentration levels of oxygen deficiency using SD rats and observed the changes of experimental animals with humidity, organic gas (toluene), hydrogen sulfide, carbon monoxide and so on at the oxygen deficient environment. The results of the study are as follows. 1. The results from the experiment conducted using SD rats at lethal concentration levels of oxygen showed that there were no casualties at the 7% oxygen concentration level, but the mortality increase to 20% at 6% oxygen, it was jumped to 90% at 5% oxygen, and it was also dramatically reached 100% at 4% oxygen concentration. Therefore, 5.5% was calculated as the $LC_{50}$ (rat, 4hr) from these dose-response experiments with oxygen deficiency. 2. When we changed the level of toluene, $H_2S$, CO, humidity, and so on, in an oxygen deficient environment, it was observed that the small concentrations of $H_2S$ and CO make the highest effect on animals. In case of 350 ppm $H_2S$, it resulted in 30% mortality, and the 100% mortality was shown in 1,200 ppm CO concentration. The mortality increased as an oxygen deficient condition. However in the case of toluene up to 1,000 ppm, it were not affected with oxygen deficiency, and it did not indicate any significant differences in mortality as 20%, 90% humidities.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.8
• /
• pp.1202-1208
• /
• 2015

The effects of daily dietary Bacillus subtilis (Bs), and adding L-tryptophan, fructan, or casein to fecal fermentation broths were investigated as means to reduce the production of noxious gas during manure fermentation caused by ammonia, hydrogen sulfide ($H_2S$), and 3-methylindole (skatole). Eighty swine ($50.0{\pm}0.5kg$) were equally apportioned to an experimental group given Bs in daily feed, or a control group without Bs. After 6 weeks, fresh manure was collected from both groups for fermentation studies using a $3{\times}3$ orthogonal array, in which tryptophan, casein, and fructan were added at various concentrations. After fermentation, the ammonia, $H_2S$, L-tryptophan, skatole, and microflora were measured. In both groups, L-tryptophan was the principle additive increasing skatole production, with significant correlation (r = 0.9992). L-tryptophan had no effect on the production of ammonia, $H_2S$, or skatole in animals fed Bs. In both groups, fructan was the principle additive that reduced $H_2S$ production (r = 0.9981). Fructan and Bs significantly interacted in $H_2S$ production (p = 0.014). Casein was the principle additive affecting the concentration of ammonia, only in the control group. Casein and Bs significantly interacted in ammonia production (p = 0.039). The predominant bacteria were Bacillus spp. CWBI B1434 (26%) in the control group, and Streptococcus alactolyticus AF201899 (36%) in the experimental group. In summary, daily dietary Bs reduced ammonia production during fecal fermentation. Lessening L-tryptophan and increasing fructan in the fermentation broth reduced skatole and $H_2S$.

• Composites Research
• /
• v.29 no.5
• /
• pp.256-261
• /
• 2016

In this work, we have prepared the filter papers with the pitch-based activated carbon fibers and the binder fibers using wet-laid process. The influence of the binder fiber on the porosity of the filter papers has been investigated by using nitrogen adsorption isotherms at 77 K and a scanning electron microscope (SEM). As a result, the specific surface area has increased with an decrease in the content of binder fiber. It has been shown that the optimum ratio of pitch-based activated carbon fibers and the binder fibers is 70:30, resulting in high porosity, excellent bonding strength, large specific surface area ($650.4m^2/g$) and high noxious gas removal efficiency (86.9%). In addition, it has been observed that the mean pore size distribution of the fiber papers has not been affected by the binder fiber.