• Title/Summary/Keyword: full-thickness

Search Result 942, Processing Time 0.021 seconds

Experimental studies on behaviour of bolted ball-cylinder joints under axial force

  • Guo, Xiaonong;Huang, Zewei;Xiong, Zhe;Yang, Shangfei;Peng, Li
    • Steel and Composite Structures
    • /
    • v.21 no.1
    • /
    • pp.137-156
    • /
    • 2016
  • Due to excellent advantages such as better illuminative effects, considerable material savings and ease and rapidness of construction, the bolted ball-cylinder joint which is a new type joint system has been proposed in space truss structures. In order to reveal more information and understanding on the behaviour of bolted ball-cylinder joints, full-scale experiments on eight bolted ball-cylinder joint specimens were conducted. Five joint specimens were subjected to axial compressive force, while another three joint specimens were subjected to axial tensile force. The parameters investigated herein were the outside diameter of hollow cylinders, the height of hollow cylinders, the thickness of hollow cylinders, ribbed stiffener and axial force. These joint specimens were collapsed by excessive deformation of hollow cylinders, punching damage of hollow cylinders, evulsion of bolts, and weld cracking. The strain distributions on the hollow cylinder opening were mainly controlled by bending moments. To improve the ultimate bearing capacity and axial stiffness of bolted ball-cylinder joints, two effective measures were developed: (1) the thickness of the hollow cylinder needed to be thicker; (2) the ribbed stiffener should be adopted. In addition, the axial stiffness of bolted ball-cylinder joints exhibited significant non-linear characteristics.

Animal Skin Pigmentation Model Using Full Thickness Skin Graft in C57BL/6 Mouse (C57BL/6 마우스의 등에 시행한 자가 전층피부이식편을 이용한 색소침착 동물모델)

  • Lee, Hong-Ki;Park, Jong-Lim;Heo, Eun-Ju;Kim, Suk-Wha
    • Archives of Plastic Surgery
    • /
    • v.38 no.6
    • /
    • pp.725-732
    • /
    • 2011
  • Purpose: Skin grafting is one of the most commonly used methods in reconstructive plastic surgery field, but complications such as color change, contracture or hypertrophy are common problems. However, pathophysiology of the color change after skin graft is not yet determined and no animal model is established. Methods: Full thickness skin grafts were performed on the dorsum of C57BL/6 mice. Serial chronological gross inspection for color change and pigmentation were examined. Melanin pigments were traced by Fontana-Masson staining and semi-quantitative analysis was performed. In addition, immunohistochemical staining of S-100, Micropthalmia related Transcription Factor (MITF) and Melan-A antibodies were also performed to observe melanocytes and their changes. Results: After skin graft, color change and pigment spots were observed in the graft. Fontana-Masson staining showed melanin pigments in the epidermal and dermal layers in all mice. Immunohistochemistry staining to S-100, MITF, Melan-A antibodies showed melanocytes at the basal layer of epidermis and dermis. Conclusion: In conclusion, we have established an animal model for skin pigmentation after skin graft. We believe this study may be useful in understanding of the behavior of melanocytes after skin graft.

Clinical Application of Autologous Platelet-Rich Plasma (PRP) on Delayed Wound Healing of a Dog with Burns

  • Lee, Shinho;Cheong, Jongtae;Lee, Joo-Myoung
    • Journal of Veterinary Clinics
    • /
    • v.35 no.5
    • /
    • pp.229-232
    • /
    • 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.

The effects of special metallic dampers on the seismic behavior of a vulnerable RC frame

  • Ozkaynak, Hasan
    • Structural Engineering and Mechanics
    • /
    • v.61 no.4
    • /
    • pp.483-496
    • /
    • 2017
  • Earthquake excitations may induce important amount of seismic energy into structures. Current design philosophy mainly deals with the plastic deformations of replaceable energy dissipating devices rather than damages accumulated on structural members. Since earthquake damage is substantially concentrated on these devices they could be replaced after severe earthquakes. In this study, the efficiency of steel cushion (SC) on seismic improvement of a vulnerable reinforced concrete (RC) frame is determined by means of several numerical simulations. The cyclic shear behaviors of SCs were determined by performing quasi-static tests. The test results were the main basis of the theoretical model of SCs which were used in the numerical analysis. These analyses were performed on three types of RC frames namely bare frame (BF), full-braced frame (F-BF) and semi-braced frame (S-BF). According to analysis results; implementation of SCs has considerable effects in reducing the storey shear forces and storey drifts. Moreover plastic energy demands of structural elements were reduced which indicates a significant improvement in seismic behavior of the RC frame preventing damage accumulation on structural elements. Full-braced frame having SCs with the thickness of 25 mm has better performance than semi-braced frame interms of energy dissipation. However, global energy dissipation demand of S-BF and F-BF having SCs with the thickness of 18 mm are almost similar.

Wound Healing Effects of Allium Cepa L. in Dogs (개에서 Allium cepa L.의 창상치유효과)

  • Moon, Kyoung-Ha;Park, Hyun-Jeong
    • Journal of Veterinary Clinics
    • /
    • v.27 no.4
    • /
    • pp.382-385
    • /
    • 2010
  • This study was performed to investigate the wound healing effects of Allium cepa L. on Staphylococcus intermedius contaminated wound. 4 full-thickness skin wounds ($2\;cm{\times}2\;cm$) were made in the back and Staphylococcus intermedius was inoculated in seven dogs. In each dog, the wounds were treated with onion extract (experimental group) and normal saline (control group), respectively. The wound contraction rate of the experimental group was higher than that of the control group during the experimental period. The occupation rate showed that the wounds of the experimental groups contracted more vigorously than that of the control group in the early period of wound healing. The mean value of tensile strength on the 22 day after wounding was $4,741{\pm}848\;g/cm^2$ in the experimental group and $2,400{\pm}397\;g/cm^2$ in the control group. The number of S. intermedius in the experimental groups was decreased more rapidly than that of the control group. These results suggest that application of activated onion extract in like full-thickness skin wounds promote wound healing.

RECONSTRUCTION OF LOWER EYELID DEFECT ; REPORT OF A CASE (하안검 전충결손의 재건의 치험례)

  • Oh, Choong-Won;Yeo, Hwan-Ho;Lee, Chul-Woo;Yang, In-Seok;Shin, Kang-Soo;Park, Cheung-Yeoul
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.14 no.3
    • /
    • pp.201-206
    • /
    • 1992
  • The eyelids perform many complex functions and are esthetically important, since eye is focal point of face. Tumor extirpation or trauma can lead to full-thickness eyelid defect, which Should be reconstructed as soon as possible There are a number of operation methods for lower lid reconstruction, and among them, Hughes procedure is a time-honored method. Its advantages are good cosmetic result and conjunctival repair by using eyelid structures to rebuild eyelid structures. However, this is a two-staged procedure in which the vision of the affected eye is obstructed during the interval between the operations. We experienced a case of trauma-induced full-thickness lower lid defect extending over one-third of lid length treated by Hughes method. The cosmetic and functional result was good and there was no donor site morbidity, and now we report this case with review of literatures.

  • PDF

Biomechanical Test for Repair Technique of Full-thickness Rotator Cuff Tear

  • Lim, Chae-Ouk;Park, Kyoung-Jin
    • Clinics in Shoulder and Elbow
    • /
    • v.19 no.1
    • /
    • pp.51-58
    • /
    • 2016
  • The arthroscopic rotator cuff repair is now considered a mainstream technique with highly satisfactory clinical results. However, concerns remain regarding healing failures for large and massive tears and high revision rate. In recent decades, various repair strategies and construct configurations have been developed for rotator cuff repair with the understanding that many factors contribute to the structural integrity of the repaired construct. The focus of biomechanical test in arthroscopic repair has been on increasing fixation strength and restoration of the footprint contact characteristics to provide early rehabilitation and improve healing. These include repaired rotator cuff tendon-footprint motion, increased tendon-footprint contact area and pressure, and tissue quality of tendon and bone. Recent studies have shown that a transosseous tunnel technique provides improved contact area and pressure between rotator cuff tendon and insertion footprint, and the technique of using double rows of suture anchors to recreate the native footprint attachment has been recently described. The transosseous equivalent suture bridge technique has the highest contact pressure and fixation force. In this review, the biomechanical tests about repair techniques of rotator cuff tear will be reviewed and discussed.

Closure of a full-thickness scalp burn that occurred during hair coloring using a simple skin-stretching method: A case report and review of the literature

  • Oh, Suk Joon
    • Archives of Plastic Surgery
    • /
    • v.46 no.2
    • /
    • pp.167-170
    • /
    • 2019
  • Full-thickness scalp burns secondary to hair coloring are rare; however, such defects can be large and complex reconstruction of hair-bearing tissue may be necessary. Many skin-stretching devices that use gradual traction have been applied to take advantage of the viscoelastic properties of the skin. A 21-year-old female patient was seen with a burn defect on her occipital scalp leading to exposed subcutaneous tissue after chemical application of hair coloring in a salon. The dimensions of the wound were $10cm{\times}5cm$, and a skin graft or flap would have been necessary to close the defect. Two long transfixing K-wires (1.4 mm) and paired 3-wire threads (23 gauge), which are readily available in most hospitals, were applied over a period of 12 days for trichophytic closure of the defect. The remaining scalp scars after primary trichophytic closure with this skin-stretching method were refined with hair follicle transplantation. This skin-stretching method is simple to apply and valuable for helping to close problematic areas of skin shortage that would otherwise require more complicated procedures. This case shows a relatively unknown complication of hair coloring and its treatment.

Choice of LECS Procedure for Benign and Malignant Gastric Tumors

  • Min, Jae-Seok;Seo, Kyung Won;Jeong, Sang-Ho
    • Journal of Gastric Cancer
    • /
    • v.21 no.2
    • /
    • pp.111-121
    • /
    • 2021
  • Laparoscopic endoscopic cooperative surgery (LECS) refers to the endoscopic dissection of the mucosal or submucosal layers with laparoscopic seromuscular resection. We recommend a treatment algorithm for the LECS procedure for gastric benign tumors according to the protruding type. In the exophytic type, endoscopic-assisted wedge resection can be performed. In the endophytic type, endoscopic-assisted wedge resection of the anterior wall is relatively easy to perform, and endoscopic-assisted transgastric resection, laparoscopic-assisted intragastric surgery, or single-incision intragastric resection in the posterior wall and esophagogastric junction (EG Jx) can be attempted. We propose an algorithm for the LECS procedure for early gastric cancer according to the tumor location. The endoscopic submucosal dissection (ESD) procedure can be adapted for all areas of the stomach, and single-incision ESD can be performed in the mid to high body and the EG Jx. In full-thickness gastric resection, laparoscopy-assisted endoscopic full-thickness resection can be adapted for the entire area of the stomach, but it cannot be applied to the pyloric and EG Jx. In conclusion, surgeons need to select the LECS procedure according to tumor type, tumor location, the surgeon's individual experience, and the situation of the institution while also considering the advantages and disadvantages of each procedure.

Chondrocutaneous posterior auricular artery perforator free flap for single-stage reconstruction of the nasal tip: a case report

  • Lee, Jun Yong;Seo, Jeong Hwa;Jung, Sung-No;Seo, Bommie Florence
    • Archives of Craniofacial Surgery
    • /
    • v.22 no.6
    • /
    • pp.337-340
    • /
    • 2021
  • Full-thickness nasal tip reconstruction is a challenging process that requires provision of ample skin and soft tissue, and intricate cartilage structure that maintains its architecture in the long term. In this report, we describe reconstruction of a full-thickness nasal tip and ala defect using a posterior auricular artery perforator based chondrocutaneous free flap. The flap consisted of two lay ers of skin covering conchal cartilage, and was based on a perforating branch of the posterior auricular artery. A superficial vein was secured at the posterior margin. The donor perforator was anastomosed to a perforating branch of the lateral nasal artery. The superficial vein was connected to a superficial vein of the surrounding soft tissue. The donor healed well after primary closure. The flap survived without complications, and the contour of the nasal rim was sustained at follow-up 6 months later. As opposed to combined composite reconstructions using a free cartilage graft together with a small free flap or pedicled nasolabial flap, the posterior auricular artery perforator free flap encompasses all required tissue types, and is similar in contour to the alar area. This flap is a useful option in single-stage reconstruction of nasal composite defects.