399 research outputs found
Creating Three-Dimensional Polymeric Microstructures by Multi-Beam Interference Lithography
It is attractive to produce true three-dimensional (3D) microstructures both rapidly and economically over a large area with negligible defects for a wide range of applications. Multi-beam interference lithography is one of the promising techniques that can create periodic microstructures in polymers without extensive lithography and etching steps. This review discusses the formation of interference patterns, their dependence on beam parameters, the lithographic process, and the applications to the formation of photonic crystals. Various photoresist systems, including thick films of negative-tone and positive-tone photoresists, liquid resins, organic-inorganic hybrids, and holographic polymer-dispersed liquid crystals, are also reviewed
Photonic Bandgap Structures of Core-Shell Simple Cubic Crystals from Holographic Lithography
We report the investigation of photonic bandgap properties of a core-shell simple cubic structure (air core with a dielectric shell) using a two-parameter level-set approach. The proposed structure can be obtained by partially backfilling high refractive index materials into a polymeric template fabricated by multi-beam interference lithography. We find that the shell formation in the inverted simple cubic structure increases the complete photonic bandgap width by 10–20% in comparison to that of a completely filled structure. The bandgap between the 5th and 6th bands begins to appear at a refractive index contrast of 2.7. This study suggests the importance to investigate the core-shell formation in three-dimensional photonic crystals through backfilling, which may offer an additional control over their photonic bandgap properties
Fabricating Three-Dimensional Polymeric Photonic Structures by Multi-Beam Interference Lithography
The fabrication of true three-dimensional (3D) microstructures both rapidly and economically over a large area with negligible defects is attractive for a wide range of applications. In particular, multi-beam interference lithography is one of the promising techniques that can mass-produce polymeric 3D photonic crystals defect-free over a large area. This review discusses the relationship between beam geometry and the symmetry of the interference patterns, the lithographic process, and various types of photoresist systems, including thick films of negative-tone and positive-tone photoresists, organic-inorganic hybrids, hydrogels, and holographic polymer-dispersed liquid crystals
Triply periodic bicontinuous structures as templates for photonic crystals: a pinch-off problem
Photonic band-gap structures of core-shell simple cubic crystals from holographic lithography
Morphological changes of the lateral meniscus in end-stage lateral compartment osteoarthritis of the knee.
OBJECTIVE: The aim of this study was to evaluate the morphological changes of the lateral meniscus in end-stage lateral compartment osteoarthritis (OA) of the knee. METHODS: One hundred fifty-eight knee joints from 133 patients that subsequently underwent total knee joint arthroplasty from January 2008 to December 2009 were enrolled. There were 26 men and 107 women. Their ages ranged from 56 to 81 (mean 67.4 + 6.5 years). All study participants had complete obliteration of the lateral joint space identified by weight-bearing radiography. Meniscal position was assessed by measuring meniscal subluxation and meniscal height. The meniscal morphology was assessed using a modification of the whole-organ magnetic resonance imaging score (WORMS). The frequency of different meniscal morphology and their respective positions was calculated. RESULTS: The predominant type (42.4%, 53.8% and 52.5% in the anterior horn, mid-body and posterior horn, respectively) of abnormal meniscal morphology was a complete maceration/destruction or complete resection. The anterior horn of non-macerated lateral meniscus was more subluxed than that of the non-macerated medial meniscus in patients with lateral OA. CONCLUSION: This study suggests that the lateral meniscus in persons with end-stage lateral OA are mostly macerated or destroyed. Also, unlike isolated end-staged medial compartment OA, the anterior horn of the lateral meniscus in isolated end-stage lateral OA is commonly affected. Copyright 2011 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved
A Xiphoid Elongation Following a Trauma Laparotomy: A Case Report
Xiphoid elongation is a rare phenomenon where the xiphoid process elongates after stimuli such as surgery, physical therapy, or trauma. We report on a 47-year-old male involved in a traffic accident who went into cardiac arrest. He received ongoing cardiopulmonary resuscitation for nine minutes before recovery of cardiac rhythm, and transfer from a local hospital to the trauma center. He received management for hypotensive shock which was temporarily corrected using Resuscitative Endovascular Balloon Occlusion of the Aorta, and underwent trauma laparotomy in which ileocolic artery ligation and a splenectomy were performed. Six months later, the patient reported epigastric discomfort when he bent over. A hard, linear mass was palpated along the upper midline incision scar and a computed tomography scan showed an elongated xiphoid process (10 cm). The patient underwent surgical excision, and electrocauterization of the xiphoid process. This is a rare case of xiphoid elongation following multiple stimuli to the xiphoid process
Fabrication of Photonic Crystals with high refractive index
• Complete photonic bandgap • High contrast of refractive index (RI) • Polymer material with a low RI • Inorganic material with a higher RI, such as silicon, titania. • Fabrication of diamond-like PCs by MBIL, • Fabrication of high RI inorganic PCs via double templating, • Core-shell morphology of replica • Pinch-off problem • Development of combined level-surface to address pinch-off problem • Electrodeposition of titania 3D structure • Electrophoretic deposition of surface charged nanoparticle
Hormonal responses upon return of spontaneous circulation after cardiac arrest: a retrospective cohort study
Age group characteristics of children who visited the emergency department with acute poisoning by ingestion
Purpose To investigate the age group characteristics of children who visited the emergency department with acute poisoning by ingestion. Methods We reviewed children under 19 years who visited the emergency department for acute poisoning by ingestion from 2012 to 2017. The children were divided into 3 age groups; infants (0-1 years), preschoolers (2-5 years), and schoolers (6-18 years). Clinical characteristics, intentional ingestion, involved substances (drugs, household products, artificial substances, and pesticides), decontamination and antidote therapy, and outcomes of the 3 age groups were compared. We also performed multivariable logistic regression analysis to identify factors associated with hospitalization. Results A total of 622 children with acute poisoning by ingestion were analyzed. Their annual proportions to overall pediatric emergency patients ranged from 0.3% to 0.4%. Age distribution showed bimodal peaks at 0-2 years and 15-17 years. The infants showed lower frequency of girls, intentional ingestion, ingestion of drugs, performance of decontamination and antidote therapy, and hospitalization than 2 older groups (P < 0.001). Most decontamination, antidote therapy, and hospitalization occurred in the schoolers (P < 0.001). The most frequently reported substances were household cleaning substances in the infants (18.2%), antihistamines in the preschoolers (15.8%), and analgesics in the schoolers (37.5%). The factors associated with hospitalization were intentional ingestion (adjusted odds ratio [aOR], 7.08; 95% confidence interval [CI], 2.85-17.61; P = 0.001) and schoolers (aOR, 2.33; 95% CI, 1.10-7.53; P = 0.031; compared with infants). Only 1 in-hospital mortality was found in a boy aged 2 years who ingested methomyl. Conclusion Infants may experience non-intentional ingestion, ingestion of non-pharmacologic substances (especially household cleaning substances), discharge without decontamination and antidote therapy more frequently than older children. Thus, we need age group-specific, preventive and therapeutic plans for children with acute poisoning
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