• Carbon letters
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• v.11 no.1
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• pp.13-21
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• 2010

Coconut shell activated carbon (CSAC) was investigated for its ability in the removal of two neutral chlorinated organic compounds, namely trichloroethylene (TCE) and dichloromethane (DCM) from aqueous solution using a packed bed column. The efficiency of the prepared activated carbon was also compared with a commercial activated carbon (CAC). The important design parameters such as flow rate and bed height were studied. In all the cases the lowest flow rate (5 mL/min) and the highest bed height (25 cm) resulted in maximum uptake and per cent removal. The experimental data were analysed using bed depth service time model (BDST) and Thomas model. The regeneration experiments including about five adsorption-desorption cycles were conducted. The suitable elutant selected from batch regeneration experiments (25% isopropyl alcohol) was used to desorb the loaded activated carbon in each cycle.

• Journal of Plant Biotechnology
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• v.3 no.1
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• pp.27-31
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• 2001

New types of cytoplasmic male sterility in Brassica species would be very useful for the production of F$_1$, hybrid seeds. Leaves and stems of rapid cycling stock of B.juncea (CrGC4-3) containing Anand CMS were used as experimental materials for plant regeneration from protoplast culture. Very high plant regeneration rate (85%) was found in the Kao & Michayluk medium supplemented with 2 mg/L zeatin, 0.5 mg/L BAP, and 1 mg/L NAA when only leaf, not stem, segments were cultured. Protoplasts were isolated from leaves using mixtures of enzymes (1% Cellulycin, 0.5% Macerozyme) in 0.4 M mannitol and 50 mM $CaCl_2$.$2H_2$O. Mcrocalli induced from protoplasts were transferred to the shoot regeneration medium containing 2 mg/L BAP, 2 mg/L zeatin, and 0.5 mg/L NAA. After 60 days of initial protoplast culture, regenerated plantlets were obtained, acclimatized, transplanted into the pots, and grown up to the flowering stage.

• Korean Journal of Medicinal Crop Science
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• v.14 no.6
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• pp.367-370
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• 2006

The study was carried out to establish an improved protocol for shoot organogenesis and plant regeneration from leaf explant cultures of Scrophularia buergeriana M. with the treatment of ethylene inhibitors [silver nitrate (AgNO$_3$), aminoethox-yvinylglycine (AVG), Cobalt chloride (CoCl$_2$)]. The regenerated shoots obtained from leaf explant cultures on MS medium containing 2 mg/l BAP, The additions of AgNO$_3$. AVG and CoC1$_2$ substantially improved the shoot regeneration frequency, at the optimal concentration of 7 mg/L, 7 mg/L, and 3 mg/L respectively, The regenerated shoots could be easily rooted with 0.1 mg/L IBA treatment. The noted plants were hardened and transferred to vermiculite with a 85% survival rate where they grew normally.

• Journal of Plant Biology
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• v.35 no.1
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• pp.17-23
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• 1992

Effects of polyamines and their biosynthetic inhibitors on adventitions shoot regeneration of Populus leaf segments were investigated. Polyamine inhibitors such as difluoromethyl arginine (DFMA), difluoromethyl ornithine (DFMO), and dicyclohexylamine (DCHA) decreased the fresh weight of cultured leaf segment and the rate of adventitious shoot regeneration. The inhibitory effects of DCHA were stronger than any other oplyamine inhibitors, and the rest were in the order of DFMO and DFMA. The inhibitory effects of these inhibitors were lessened or disappeared by the addition of polyamines, among which spermidine was the highest in its effect. Therefore, it is suggested that the spermidine may be related to the adventitious shoot regeneration of Populus leaf segments.gments.

• Journal of the Korean Solar Energy Society
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• v.23 no.3
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• pp.7-14
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• 2003

Absorption potential of desiccant solution significantly decreases after absorbing moisture from humid air, and a regeneration process requires a great amount of energy to recover absorption potential of desiccant solution. In an effort to develop an energy efficient regenerator, this study examines a regeneration process using hot air heated by solar radiation to recover absorption potential by evaporating moisture in liquid desiccant. More specifically, this study is aimed at finding the optimum operating condition of the regenerator by utilizing a well-established statistical tool, so-called response surface methodology(RSM), which may provide a functional relationship between independent and dependent variables. It is demonstrated that an optimization model to find the optimum operating condition can be obtained using the functional relationship between regeneration rate and affecting factors which is approximated on the basis experimental results.

• FOCUS: LIFE SCIENCE
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• no.1
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• pp.5.1-5.3
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• 2024

The document discusses the regeneration of Partisil/Partisphere ion-exchange columns in chromatography. It mentions that column efficiency can diminish with use due to the accumulation of sample and/or mobile phase impurities at the head of the column. This can lead to a change in back pressure, lower column efficiency, and sometimes a change in selectivity. The document outlines a procedure that may restore column performance. The document also provides everyday practices to enhance the lifetime of a column. These include using only high-purity HPLC solvents and buffers, using freshly prepared mobile phases and buffers, filtering mobile phases to remove particulates, using appropriate sample clean-up procedures, using a guard column or pre-column filter, and working within the pressure and flow rate limitations of the column. For the regeneration of Partisil/Partisphere SAX, SCX, WAX, and WCX columns, the document suggests passing 20 column volumes of various mobile phases through the column. These include a buffer wash, distilled water, an acid wash, a chelating wash, a methanol wash, and a buffer for separation. The document emphasizes that not all of these wash steps are required for every column clean-up and that some chromatographers require only a combination of certain steps.

• Journal of Periodontal and Implant Science
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• v.44 no.1
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• pp.13-19
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• 2014

Purpose: The purpose of this study was to retrospectively evaluate the survival of periodontally hopeless teeth that were intentionally extracted and replanted after a delay and to compare the radiographic characteristics of the survival group with those of the failure group. Methods: The clinical and radiographic data from patients who underwent delayed intentional replantation between March 2000 and July 2010 were reviewed. Twenty-seven periodontally hopeless teeth were extracted and preserved in medium supplemented with antibiotics for 10-14 days. The teeth were then repositioned in the partially healed extraction socket and followed for 3 to 21 months. The radiographic parameters were analyzed using a paired t test and the cumulative survival rate was analyzed using Kaplan-Meier analysis. Results: Seven replanted teeth failed and the overall cumulative survival rate was 66.4%. In the survival group, the amount of bone loss was reduced from 68.45% to 34.66% three months after replantation. There was radiologic and clinical evidence of ankylosis with 5 teeth. However, no root resorption was found throughout the follow-up period. In the failure group, bone formation occurred from the bottom of the socket. However, a remarkable radiolucent line along the root of a replanted tooth existed. The line lengthened and thickened as time passed. Finally, in each case of failure, the tooth was extracted due to signs of inflammation and increased mobility. Conclusions: Delayed intentional replantation has many advantages compared to immediate intentional replantation and could serve as an alternative treatment for periodontally involved hopeless teeth. However, techniques for maintaining the vitality of periodontal structures on the tooth surface should be developed for improved and predictable results.

• Journal of Periodontal and Implant Science
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• v.35 no.3
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• pp.597-608
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• 2005

The aim of this study is to determine whether full-mouth disinfection therapy(FMT) in our clinical setting would show better improvement of clinical parameters than partial mouth disinfection therapy(PMT) in chronic periodontitis and aggressive periodontitis patients. Among 12 patients, 6 were treated FMT and other 6 were treated PMT. Clinical parameters were calculated 3 months and 6 months after initial therapy. 1. There were no statistically significant differences between FMT and PMT in the reduction rate of bleeding on probing after 3 months, 6 months 2. Initial probing depth was 4-6mm, the mean probing depth after 3 months was 2.2mm vs 2.5mm(FMT vs PMT), after 6 months was 2.4mm vs 2.8mm. This was significantly lower in the FMT groups. 3. Initial probing depth was ${\geqq}$ 7mm, the reduction rate of mean probing depth during first 3 months was 4.8mm vs 4.1mm(FMT vs PMT), and 3 to 6 months was 0.5mm vs 0.3mm. This was significantly larger in the FMT groups. 4. Initial probing depth was 4-6mm, the mean clinical attachment level after 3 months was 2.3mm vs 2.7mm(FMT vs PMT), after 6 months was 2.7mm vs 3.0mm. This was significantly lower in the FMT groups. 5. Initial probing depth was ${\geqq}$ 7mm, the reduction rate of mean probing depth during first 3 months was 4.0mm vs 3.0mm(FMT vs PMT), and 3 to 6 months was 0mm vs -0.1mm. This was significantly larger in the FMT groups. Although the results provided us with succeccful clinical improvement in aggressive periodontitis, further research is needed to prove its additional benefit in the treatment of chronic periodontitis

• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.673-691
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• 2003

The current interest in periodontal tissue regeneration has lead to research in bone graft, root surface treatments, guided-tissue regeneration, and the administration of growth factors as possible means of regenerating lost periodontal tissue. Several studies have shown that a strong correlation between platelet-rich plasma and the stimulation of remodeling and remineralization of grafted bone exists, resulting in a possible increase of 15-30% in the density of bone trabeculae. The purpose of this study was to study the histopathological correlation between the use of platelet-rich plasma and a bone xenograft used in conjunction with a non-resorbable guided-tissue membrane, e-PTFE, compared to a control group with regards to bone regeneration at the implant fixture site. Implant fixtures were inserted and graft materials placed into the left femur of in the experimental group, while the control group received only implant fixtures. In the first experimental group, platelet-rich plasma and BBP xenograft were placed at the implant fixture site, and the second experimental group had platelet-rich plasma, BBP xenograft, and the e-PTFE membrane placed at the fixture site. The degree of bone regeneration adjacent to the implant fixture was observed and compared histopathologically at 2 , 4, and 8 weeks after implant fixture insertion. The results of the experiment are as follows: 1. The rate of osseointegration to the fixture threads was found to be greater in the first experimental group compared to the control group. 2. The histopathological findings of the second experimental group showed rapid resorption of BBP with subsequent new bone formation replacing the resorbed BBP. 3. The second experimental group showed new bone formation in the area adjacent to the fixture threads beginning two weeks after fixture implantation, with continued bone remodeling in the areas mesial and distal to the fixture. 4. Significant new bone formation and bone remodeling was observed in both experimental groups near the implant fixture sites. 5. The rate of osseointegration at the fixture threads was greater in the second experimental group compared to the first group, and the formation of new bone and trabeculae around the fixture site occurred after the fourth week in the second experimental group. The results of the experiment suggest that a greater degree of new bone formation and osseointegration can occur at the implant fixture site by utilizing platelet-rich plasma and bone xenografts, and that these effects can be accelerated and enhanced by concurrent use of a non-resorbable guided tissue membrane.

• The Korean Journal of Mycology
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• v.14 no.3
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• pp.215-223
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• 1986

Protoplasts of P. cornucopiae were reverted to normal hyphal growth and reversion frequency was $0.04{\sim}19%$. The complete medium stabilized with 0.6 M sucrose was most effective for regeneration of protoplasts. When hypertonic mushroom complete medium not containing agar was overlaid, regeneration frequency of protoplasts was the highest rate among the others of topagar. The protoplast reversion frequency and mycelial growth of P. cornucopiae were increased when various amino acids, nucleic acid components and vitamin compound were added to the hypertonic minimal medium. The relation between sources increasing reversion frequency and sources accelerating mycelial growth was similar in amino acids and nucleic acid components but it was different in vitamins. The protoplast reversion frequency showed the highest rate when all sources were added to the regeneration minimal medium. Microscopically, regeneration patterns of protoplasts showed formation of a bud-like structure, direct germination, yeast-like cell chain of the protoplast, and the production of both direct germ tube and yeast-like cell chain from a protoplast.