• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.367-374
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• 2021

In this study, the applicability of mechanochemical process for the manufacture of self-healing admixtures and the effect of mechanochemical process on the self-healing performance were evaluated. The self-healing admixtures were adopted as a highly reactive materials(expansive agent, swelling material and crystal growth agent) for mechanochemical processes. The self-healing admixtures for the mechanochemical process application were evaluated by X-Ray Diffraction and Fourier Transform Infrared Spectroscopy analysis, water permeability performance was used to evaluate self-healing performance of mortar. As a result of the evaluation, the self-healing performance of the WM(With-Mortar)3 sample to which mechanochemical process increased by 4.1% compared to the WM1 sample that was not treated, and the average healing index was 94.3%.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.531-538
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• 2022

In this study, the self-healing hybrid capsules were prepared, were mixed with 3 %, 5 %, and 7 % based on cement mass. The healing performance were evaluated according to mixing ratio self-healing hybrid capsule. As a result of the experiment, it was found that the crack healing performance improved as the mixing rate of the self-healing hybrid capsule increased, but the quality performance tended to decrease. Therefore, it is judged that using the mixing ratio of the hybrid capsule within 5 % reduces the quality performance to within about 10 % and secures about 90 % or more of the healing performance.

• The Journal of the Korean dental association
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• v.10 no.12
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• pp.813-816
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• 1972

The authors have observed 207 cases on the results of pulp healing after pulp capping. The results are as follows: 1) We could have success-rate of 70% in 207 cases at the ages from 14 to 59. 2) The success-rate in male is 72.4% in 87 cases, and female is 67.5% in 120 cases. So we observed that success-rate was slightly higher in male than female. 3) In view of age group, it was observed that success-rate was 79% in 129 cases at 30 ages below, 62.5% in 40 cases at 30-40 ages, 47.3% in 38 cases at 40 ages over. So we found that the failure-rate was increased by aging.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.561-568
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• 2022

In this study, the mechanical properties and self-healing performance of cement mortar containing clinker binder, calcium sulfoaluminate(CSA), and sodium sulfate(Na₂SO₄) were evaluated. The mechanical properties of cement mortar were investigated by measuring compressive strength and flexural strength, and the healing performance was evaluated through hydrostatic water permeability test and gas diffusion test. In addition, the healing products precipitated in the cracks were visually observed through an optical microscope and a scanning electron microscope(SEM). As a result, the incorporation of the clinker binder-based inorganic additives improved the initial and 28-day strength by about 20 %. Depending on the healing performance evaluation method, there was a difference in the healing rate, and the healing rate showed a tendency to be underestimated. Nevertheless, CaCO₃ was precipitated as the main healing product inside the 0.3 mm crack when the inorganic additives were mixed with cement mortar, improving the self-healing performance.

• Journal of the Korean Society for Precision Engineering
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• v.3 no.1
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• pp.40-49
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• 1986

Crack, craze and void are common defects which may be found in the bulk of polymeric materials such as either themoplastics or thermosets. The healing phenomena, autohesion, of these defects are known to be a intrinsic material property of various polymeric materials. However, only a few experimental and theoretical investigations on crack, void and craze healing phenomena for various polymeric materials have been reported up to date [1, 2, 3]. This may be partly due to the complications of healing processes and lacking of appropriate theoretical developments. Recently, some investigators have been urged to study the healing phenomena of various polymenic materials since the significance of the use of polymer based alloys or composites has been raised in terms of specific strength and energy saving. In the earlier published reports [1, 2, 3, 4], the crack and void healing velocity, healing toughness and some other healing mechanical and physical properties were measured experimentally and compared with predicted values by utilizing a simple model such as the reptation model under some resonable assumptions. It seems, however, that the general acceptance of the proposed modeling analyses is yet open question. The crack healing processes seem to be complicate and highly dependent on the state of virgin material in terms of mechanical and physical properties. Furthermore, it is also strongly dependent on the histories of crack, craze and void development including fracture suface morphology, the shape of void and the degree of disentanglement of fibril in the craze. The rate of crack healing may be a function of environmental factors such as healing temperature, time and pressure which gives different contact configurations between two separated surfaces. It seems to be reasonable to assume that the crack healing processes may be divided in several distinguished steps like stress relaxation with molecular chain arrangement, surface contact (wetting), inter- diffusion process and com;oete healing (to obtain the original strength). In this context, it is likely that we no longer have to accept the limitation of cumulative damage theories and fatigue life if it is probable to remove the defects such as crack, craze and void and to restore the original strength of polymers or polymer based compowites by suitable choice of healing histories and methods. In this paper, we wish to present a very simple and intuitive theoretical model for the prediction of healed fracture toughness of cracked or defective polymeric components. The central idea of this investigation, thus, may be the modeling of behavior of chain molecules under healing conditions including the effects of chain scission on the healing processes. The validity of this proposed model will be studied by making comparisons between theoretically predicted values and experimentally determined results in near future and will be reported elsewhere.

• Journal of Veterinary Clinics
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• v.35 no.5
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• pp.229-232
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• 2018

A 9-year-old intact female Poodle (weighing 3.6 kg) was presented for the treatment of a partial and full thickness burn that covering 45% of body including bilateral thigh and sacrolumbar region. Autologous platelet-rich plasma (PRP) stimulates angiogenesis, promoting vascular in-growth and fibroblast proliferation. On the unrecovered right thigh of the dog, autologous PRP was injected into the lesion after application of micro-needles. For macroscopic evaluation digital, photographs were taken from wounds at days 0, 3, 5, 13, 21, and 28. On the $3^{rd}$ day after PRP application, epithelialization was accelerated. Application of autologous PRP accelerated wound-healing rate and healing time in full thickness burns as well as secondary complications originating from unrecovered wounds. The delayed lesion was completely healed on the $28^{th}$ day by autologous PRP treatment. In human, PRP was increasingly used in the treatment of a variety of soft tissue in the management of chronic non-healing wounds. This study has shown that PRP treatment can be a valuable and effective aid on intractable wound healing in the dog with burns.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.585-589
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• 2011

Purpose: Microcirculation of diabetic patients is commonly comporomised, regardless of the condition of the macrocirculation. Therefore, direct tissue oxygenation measurement is recommended in determining tissue viability and predicting wound healing potential. This study was designed to determine cut-off value of the tissue oxygenation in predicting wound healing in diabetic foot patients. Methods: This study included 41 feet of 41 diabetic foot patients who were treated in the Diabetic Wound Center of author's institution between January and June, 2009. Main inclusion criteria were type 1 or 2 diabetes and a foot ulcer (duration > 3 weeks) and ulcer area (from 1 $cm^2$ to 4 $cm^2$). Measurements of the area of diabetic foot ulcer were carried out before treatment. Transcutaneous oxygen pressure ($TcpO_2$) was measured at adjacent site of ulcer. The healing wound was defined as complete wound closure within 12 weeks. Results: Average diabetic foot ulcer areas with healing and nonhealing wounds were $2.67{\pm}0.76$ and $2.59{\pm}0.75\;cm^2$, respectively. There was no significant difference in the wound area between the groups. Average foot $TcpO_2$ in healing and nonhealing wounds were $68.56{\pm}23.07$ and $30.98{\pm}16.66$ mmHg, respectively ($p$ <0.01). The rate of healing wound increased as $TcpO_2$ increased. In particular, $TcpO_2$ lower than 40 mmHg and higher than 40 mmHg showed the most significant difference (wound healing rates of 25% and 71%, respectively). Conclusion: Based on the results of the study, the minimal $TcpO_2$ value thought to be required for adequate wound healing in diabetic wounds (cut-off value) is 40 mmHg.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.59-66
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• 2020

In this study, self - healing solid capsules of crystal growth type which can be mixed directly with repair mortar were prepared, and the quality and crack healing performance of repair mortar with self - healing solid capsules were evaluated. The table flow and the air flow rate of the repair mortar material mixed with self-healing solid capsules were found to have no significant influence on table flow and air volume regardless of mixing ratio. Compressive strength tended to decrease with increasing capsule mixing ratio. As a result of evaluation of crack healing properties according to constant water head permeability test, initial water permeability decreased, and reaction products were generated over time and cracks were healed.

• Journal of Korean Foot and Ankle Society
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• v.23 no.1
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• pp.18-23
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• 2019

Purpose: This study compared and analyzed the risk factors that affect a wound healing group and healing failure group. Materials and Methods: From 2010 to 2018, 39 patients who had suffered a single toe amputation were evaluated retrospectively. The patients were divided into two groups (wound healing group and healing failure group - within at least 3 months following the amputation). Regarding the possible risk factors, age, gender, Wagner and Brodsky classifications, duration of diabetes mellitus, whether the patient had peripheral arterial occlusive disease (PAOD) or cardiovascular disease, body mass index, HbA1c, total cholesterol, estimated glomerular filtration rate (eGFR), blood urea nitrogen (BUN), smoking, and alcohol were investigated. Results: The mean duration of diabetes mellitus was 140 months in the healing group and 227 months in the healing failure group, and the duration of diabetes was significantly longer in the failure group (p=0.009). A significant difference in eGFR was observed between the two groups ($59.17mL/min/1.73m^2$ in the healing group and $31.1mL/min/1.73m^2$ in the failure group) (p=0.022). Sixteen patients with PAOD were found, all 10 patients in the healing failure group were PAOD patients. Conclusion: To reduce the additional complications in single toe amputation patients, the underlying disease and appropriate treatment are the most important factors. In addition, a more proximal level of amputation also should be considered in cases of patients with PAOD, high BUN and low eGFR, and patients with long-term diabetes.

• Journal of Naturopathy
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• v.8 no.2
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• pp.88-92
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• 2019

Purpose: The purpose of this study was to study the efficacy of qigong therapy for various illnesses. Methods: Healing of a variety of patients and people connected to a hospital at the East-West Medical Hospital in Vienna, Austria, was carried out. A total of 38 healers healed from 1,131 people in a total of 3 times in the hospital, and the evaluation of healing efficiency conducted by 134 physician evaluation teams in the hospital itself. Results: In 2002, 80% of the patients had a "good" healing efficiency for 96 patients treated at the first session in the hospital. In the second round of 2004, the satisfaction rate of healing efficiency was over 75%. In the third session in 2006, 71.6% were satisfied with the satisfaction level of "Good," and 1,131 people evaluated with an average of 75.5%. This result suggests that qigong healing is very efficient. Conclusions: The average healing efficiency of soojung qigong for various diseases was 75.5% or higher, indicating that qigong is one of the best natural healing therapies.