• Journal of Chest Surgery
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• v.21 no.6
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• pp.1084-1094
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• 1988

Conservative management of 3 iatrogenic perforations of intrathoracic esophagus was reviewed. The primary disorders were achalasia in 2 patients and congenital tracheoesophageal fistula in 1 patient. Perforation occurred after treatment of the primary disorders in the distal esophagus in 2 patients and mid-thoracic esophagus in 1 patient. All the perforations appeared late after the previous treatments and the inflammation spread to mediastinum and pleural cavity in all the 3 patients. Conservative management of esophageal perforation was carried out with intraluminal drainage from the perforated site of esophagus[insertion of Levin`s tube and continuous suction], pleural drainage and feeding of liquid diet through gastrostomy tube with Fowler`s position. The patients revealed spontaneous closure of perforated sites about 3 to 4 weeks after this conservative management without open thoracotomy. This result suggests that this conservative management may be accepted as therapeutic method in the thoracic esophageal perforations regardless of cause and time of the perforation.

• Journal of Chest Surgery
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• v.26 no.8
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• pp.633-637
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• 1993

Twenty-five patients with perforation of esophagus were managed at Pusan National University Hospital, from 1981 to 1993. The hospital course of 14 of these patients was evaluated with a special emphasis on the cause and location of perforation, clinical presentation, time elapsed from perforation to treatment, method of treatment, and outcome. Patients with anastomotic leak and cancer were excluded.The perforation was iatrogenic in 7 patients, spontaneous in 5, ingestion of foreign body in 1, and traumatic in 1. There were 7 cervical perforations, 2 upper thoracic perforations, and 5 lower thoracic perforations. Chest pain, fever, and dyspnea were frequent symptoms. Esophagography was most diagnostic [11 patients] but thoracentesis was of little diagnostic aid.Antibiotics were administered intravenously to all patients:hyperalimentation was accomplished intravenously in 11, and nasogastric suction was used in all cases. No patient required any surgical procedure, minor or major.

• Journal of the Korean Wood Science and Technology
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• v.26 no.2
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• pp.24-28
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• 1998

Ray cells with perforations are recorded for the first time in the Korean Celastraceae species of Euonymus sieboldiana and Tripterygium regelii and the Oleaceae species of Abeliophyllum distichum, Forsythia ovata, Ligustrum japonicum, and Osmanthus heterophylla, All these anomalous ray cells have simple perforations, and the vessel elements of all these species have simple perforation plates, Thus, in the Korean Celastraceae and Oleaceae, the perforations of ray cells appear to be identical with the types of perforation plates in the vessel elements of the same wood, The diagnostic value of the perforated ray cells is also discussed.

• Steel and Composite Structures
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• v.44 no.5
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• pp.685-690
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• 2022

In this paper, the equivalent material properties of cellular metamaterials with different types of perforations have been presented using finite element (FE) simulation of tensile test in Abaqus commercial software. To this end, a Representative Volume Element (RVE) has been considered for each type of cellular metamaterial with regular array of circular, square, oval and rectangular perforations. Furthermore, both straight and perpendicular patterns of oval and rectangular perforations have been studied. By applying Periodic Boundary conditions (PBC) on the RVE, the actual behavior of cellular material under uniaxial tension has been simulated. Finally, the effective Young's modulus, Poisson's ratio and mass density of various metamaterials have been presented as functions of relative density of the RVE

• Clinical and Experimental Pediatrics
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• v.58 no.8
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• pp.288-293
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• 2015

Purpose: In this study, we aimed to review the clinical presentation of preterm infants with gastrointestinal perforations and compare the clinical features of gastric perforation with other intestinal perforations. Methods: The medical records of preterm neonates with pneumoperitoneum, admitted to the neonatal intensive care unit (NICU) between January 1994 and December 2013, were retrospectively reviewed. Results: Twenty-one preterm infants underwent exploratory laparotomy to investigate the cause of the pneumoperitoneum. The sample consisted of five patients (23.8%) with gastric perforation and 16 patients (76.2%) with intestinal perforation. No statistical differences were found in the birth history and other perinatal factors between the two groups. Underlying necrotizing enterocolitis, bilious vomiting, and paralytic ileus preceding the perforation were statistically more common in the intestinal perforation group. All preterm infants with gastric perforation survived to discharge; however, six preterm infants with intestinal perforation expired during treatment in the NICU. In the gastric perforation group, sudden pneumoperitoneum was the most common finding, and the mean age at diagnosis was $4.4{\pm}1.7days$ of life. The location and size of the perforations varied, and simple closure or partial gastrectomy was performed. Conclusion: Patients with gastric perforation did not have a common clinical finding preceding the perforation diagnosis. Although mortality in previous studies was high, all patients survived to discharge in the present study. When a preterm infant aged less than one week presents with sudden abdominal distension and pneumoperitoneum, gastric perforation should first be excluded. Prompt exploratory laparotomy will increase the survival rates of these infants.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.3
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• pp.241-249
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• 2007

An augmentation of the maxillary sinus floor facilitates placement of dental implants in the posterior atrophic maxilla. However, a maxillary sinus augmentation has potential complications that can lead to early failure and loss of the bone graft. One specific complication is sinus membrane perforation. Especially, large perforations may cause loss of the graft materials into the sinus and infection, so, early failure of the sinus lift. Attempts at managing sinus membrane perforations are difficult because of the limited access to them and friability of the thin Schneiderian membrane. Repair of sinus membrane perforations intraoperatively may be performed using a variety of techniques and materials, including sutures, collagen membranes, fibrin glue. Inspite of various repair technique, as has been reported extensively in the literature, large perforations represent an absolute contraindication to the continuation of surgery. But, we obtained clinically favorable results in cases that show repair of the perforated sinus membrane with a micro-suture technique by 4X Loupe ($Surgitel^{(R)}$ Loupe, General Scientific Corporation) in large perforation. The objective of this presentation is to report of several cases of repair of the perforated sinus membrane with micro-suture technique using 7.0 or 8.0 suture materials, to make a brief review of the literature about various technique managing perforated sinus membrane.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.11 no.1
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• pp.80-83
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• 2008

Behcet's disease (BD) is a multisystem inflammatory disorder dominated clinically by recurrent oral and genital ulceration, uveitis and erythema nodosum. BD is very rare in children, especially those less than 10 years of age, who account for only an estimated 5% of all cases. Gastrointestinal ulcers, in patients with Behcet's disease with intestinal involvement are rare and have been reported in only 1-2% of all cases. The intestinal ulcers of Behcet's disease are usually multiple and scattered and tend to cause perforations associated with significant morbidity. Patients with BD and abdominal symptoms must be evaluated thoroughly for potential perforation of the gastrointestinal tract. Here we report the case of a 4 year 9 month old child with multiple perforations of the gastrointestinal tract associated with BD.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.4
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• pp.188-194
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• 2014

For large membrane perforations that develop during sinus-bone grafting, we performed repairs using a pedicled buccal fat pad and a resorbable collagen membrane simultaneously with the bone graft. This study included eight patients. Postoperative maxillary sinusitis developed in two patients, which we managed with incision and drainage, and antibiotics. Ultimately, six patients received 12 implants, three of which failed (75% success). Implant replacement was performed after the removal of the failed replacement, at which point the prosthetic treatment was considered complete. In all of the six cases that we were able to follow-up with, the sinus-bone graft was healing favorably. We observed that the sinus bone height decreased gradually with time. Based on these case series, we conclude that our procedure of repairing large sinus-membrane perforations with a pedicled buccal fat pad and a collagen membrane is a reliable technique.

• Steel and Composite Structures
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• v.16 no.6
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• pp.657-679
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• 2014

This paper describes a series of compression tests performed on cold-formed steel channel sections with perforations in the web (thermal studs) fabricated from a galvanized steel plate whose thickness ranged from 1.0 mm to 1.6 mm and nominal yield stress was 295 MPa. The structural behavior and performance of thermal studs undergoing local, distortional, or flexural-torsional buckling were investigated experimentally and analytically. The compression tests indicate that the slits in the web had significant negative effects on the buckling and ultimate strength of thin-walled channel section columns. The compressive strength of perforated thermal studs was estimated using equivalent solid channel sections of reduced thickness instead of the studs. The direct strength method, a newly developed and adopted alternative to the effective width method for designing cold-formed steel sections in the AISI Standard S100 (2004) and AS/NZS 4600 (Standard Australia 2005), was calibrated to the test results for its application to cold-formed channel sections with slits in the web. The results verify that the DSM can predict the ultimate strength of channel section columns with slits in the web by substituting equivalent solid sections of reduced thickness for them.

• Advances in aircraft and spacecraft science
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• v.10 no.2
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• pp.179-202
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• 2023

This article presents a numerical analysis to investigate the natural frequencies and harmonic response of a perforated cantilever beam attached to two layers of piezoelectric materials by using the finite element method for the first time. The bimorph piezoelectric is composed of 3 layers; two of them at the outer are piezoelectric, and the inner isotropic material. A higher order 3-D 20-node solid element that exhibits quadratic displacement behavior is exploited to discretize the isotropic layer, and coupled piezoelectric 3D element with twenty nodes is used to mesh the top and bottom layers. CIRCU94 element is added to act as a resistor part of the model. The proposed model is validated with previous works. The numerical parametric studies are presented to illustrate the effects of perforation geometry, the number of rows, the resistance on the natural frequencies, frequency response, and power. It is found that the thickness has a positive relationship with the natural frequency. Perforations help in producing higher voltage, and the best shape is rectangular perforations, and to produce higher voltage, two rows of rectangular perforations should be applied.