• Journal of Pharmaceutical Investigation
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• v.2 no.1
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• pp.5-13
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• 1972

There are some repels in which they studied on the change of acid-consuming capacity of aluminium hydroxide resulted from the passing of time. However, the relationship between grain sizes(particle sizes) and the acid-consuming capacity of dried aluminium hydroxide gel was not been studied. And studies on the grain sizes of aluminium hydroxide gel qualified by pharmacopoeia of Korea has not been reported. For the purpose of studying these two problems, the author prepared two-kinds of aluminium hydroxide gel as follows : $Na_2OAl_2O_3+CO_2------{\longrightarrow}Al(OH)_3{\cdots}{\cdots}{\cdots}$sample 1 $Al_2(SO_4)_318H_2O+6NaHCO_3{\longrightarrow}Al(OH)_3{\cdots}{\cdots}{\cdots}$sample 2 Both of sample 1 and 2 are found to be amorphous by X-ray diffraction methods, and their acid-consuming capacities were determined by the method of pharmacopeia of Korea. The grain size was measured by X-ray diffraction method, the particle sizes observed by electron microscopy, and the change of acid-consuming capacity with passing of time was determined by the method of pharmacopoeia of Korea. The results of these studies are summerized as follows: 1. The grain size was linearly enlarged as the time goes by. The aluminium hydroxide gel gradually crystallized in a certain period of time. 2. The acid-consuming capacity was in exponential function, decreased as the grain size of them enlarged. 3. One particle consists of tens of grains.4. Grinding the Sample obtained in any period of testing time in mortar did not change both their grain size and their acid-consuming capacity. 5. The grain size of dried aluminium hydroxide gel ought to be micronized less than $100{\AA}$ for maintaining the ability such as consumes 250m1 of 0. 1N-HC1 solution per Is of $Al(OH)_3$ described in pharmacopoeia of Korea.

• Animal Bioscience
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• v.35 no.12
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• pp.1817-1826
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• 2022

Public concern on the methods of raising food-producing animals has increased, especially in the last two decades, leading to voluntary and mandated changes in the animal production methods. The primary objective of these changes is to improve the welfare of farm animals. The use of gestational stalls is currently a major welfare issue in swine production. Several studies assessed the welfare of alternative housing systems for gestating sows. A comparative study was performed with gestating sows housed in either individual stalls or in groups in a pen with an electronic sow feeder. This review assessed the welfare of each housing system using physiological, behavioral, and reproductive performance criteria. The current review identified clear advantages and disadvantages of each housing system. Individual stall housing allowed each sow to be given an individually tailored diet without competition, but the sows had behavioral restrictions and showed stereotypical behaviors (e.g., bar biting, nosing, palate grinding, etc.). Group-housed sows had increased opportunities to display such behavior (e.g., ability to move around and social interactions); however, a higher prevalence of aggressive behavior, especially first mixing in static group type, caused a negative impact on longevity (more body lesions, scratch and bite injuries, and lameness, especially in subordinate sows). Conclusively, a more segmented and diversified welfare assessment could be beneficial for a precise evaluation of each housing system for sows. Further efforts should be made to reduce aggression-driven injuries and design housing systems (feeding regimen, floor, bedding, etc.) to improve the welfare of group-housed sows.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.2
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• pp.121-130
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• 2014

Purpose: To assess the surface profile of dentinal wall, dentin chips and smear layer during the canal shaping with rotary (ProTaper) and ProFile and reciprocating (WaveOne) nickel-titanium file. Materials and Methods: Sixty human extracted mandibular premolars and incisors with single canals were randomly selected. Three experimental groups (n = 20) were instrumented with ProTaper (F2), ProFile (25/.06), WaveOne (25/.08) with irrigation of 2.5% NaOCl. The dentin chips were collected from flute of file during each canal preparation. After canal preparation, roots were grinded and each group was divided into two subgroups (n = 10) for surface profile and smear layer of dentinal wall of shaped root canal. Each specimen was observed under scanning electron microscope for evaluating size of dentin chips, root canal surface recessions and smear layer. Scores of Smear layer were statistically analyzed using Kruskal Wallis test and Mann Whitney test at P = 0.05 level. Results: The size of dentin chips from ProFile, ProTaper and WaveOne was up to $7{\mu}m$, $6.5{\mu}m$, and$4{\mu}m$, respectively. In the surface profile, the width of surface irregularity was measured and Profile, ProTaper and WaveOne was up to $150{\mu}m$, $70{\mu}m$, and $80{\mu}m$, respectively. Completely cleaned root canals were not found. In the middle and apical third of the canals, WaveOne group showed higher smear layer score than ProFile and ProTaper groups (P < 0.05). Conclusion: Within limits of this study, reciprocating motion WaveOne group was not significant difference of shaping ability with the full-sequence ProFile and ProTaper systems except canal clearness of middle and apical third of root canal. When using WaveOne to shaping root canal, thorough root canal irrigation is recommended.