ABSTRACT
On-demand NW light sources in a photonic integrated circuit (PIC) have faced several practical challenges. Here, we report on an all-graphene-contact, electrically pumped, on-demand transferrable NW source that is fabricated by implementing an all-graphene-contact approach in combination with a highly accurate microtransfer printing technique. A vertically p-i-n-doped top-down-fabricated semiconductor NW with optical gain structures is electrically pumped through the patterned multilayered graphene contacts. Electroluminescence (EL) spectroscopy results reveal that the electrically driven NW device exhibits strong EL emission between the contacts and displays waveguiding properties. Further, a single NW device is precisely integrated into an existing photonic waveguide to perform light coupling and waveguiding experiments. Three-dimensional numerical simulation results show a good agreement with experimental observations. We believe that our all-graphene-contact approach is readily applicable to various micro/nanostructures and devices, which facilitates stable electrical operation and thus extends their practical applicability in compact integrated circuits.
ABSTRACT
PURPOSE: This study attempted to evaluate a series of patients with hereditary multiple exostoses (HME) who could not be categorized according to the widely accepted Masada classification and to identify radiographic variables such as radial bowing, ulnar shortening, ulnar variance, radial articular angle, and carpal slip predictive of deformity. METHODS: We retrospectively reviewed data on 102 upper limbs of 53 pediatric patients with HME. Demographics, site of forearm involvement, and radiographic parameters were documented. Patients with exostoses of the forearms were categorized into 6 groups based on location of the exostoses and presence or absence of a dislocated radial head. Proportional ulnar shortening was calculated as the ratio of ulnar length to radial length. RESULTS: According to the Masada classification, 4 limbs were normal, 10 were type I, 2 were type II, and 24 were type III. Sixty-six limbs were unclassifiable. We classified those 66 limbs using a modification of the Masada classification. Of the 106 limbs, 11 (10.3%) had a dislocated radial head. Based on the radiographic analysis, patients with proportional ulnar shortening of less than 0.9 had a higher risk of radial head dislocation than did those with proportional ulnar shortening of 0.9 or greater. Patients with radial bowing greater than 8.1% showed a higher frequency of radial head dislocation than did those with radial bowing of 8.1% or less. Exostoses of both the distal radius and ulna tended to increase the rate of radial head dislocation. A greater amount of negative ulnar variance caused more radial bowing and a greater radioarticular angle. CONCLUSIONS: We propose a new comprehensive forearm classification for patients with HME. Proportional ulnar shortening less than 0.9 and radial bowing 8.1% or greater can be used to predict the risk of radial head dislocation. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.
Subject(s)
Exostoses, Multiple Hereditary/diagnostic imaging , Forearm/abnormalities , Joint Dislocations/diagnostic imaging , Radius/diagnostic imaging , Upper Extremity Deformities, Congenital/classification , Upper Extremity Deformities, Congenital/diagnostic imaging , Adolescent , Adult , Child , Child, Preschool , Exostoses, Multiple Hereditary/complications , Female , Forearm/diagnostic imaging , Humans , Male , Radius/abnormalities , Retrospective Studies , Ulna/abnormalities , Ulna/diagnostic imaging , Wrist Joint/diagnostic imaging , Young AdultABSTRACT
Coupled optical cavities are an attractive on-chip optical platform for realizing quantum mechanical concepts in electrodynamics and further developing non-Hermitian photonics. In such systems, an intercavity interaction is often considered as a key parameter to understand the system's behaviors but its estimation/calculation is typically limited for some simplified systems owing to extended complexities. For example, multi-coupled photonic crystal (PhC) nanocavities exhibiting strong resonances with a large free spectral range can serve as an excellent test-bed to study non-Hermitian optical properties when spatially non-uniform gain is introduced. However, the detailed quantitative analysis such as spectral tracing of cavity normal modes is often limited in commercially available numerical tools because of the required massive computation resources. Herein, we report on a concept of spatial overlap integrals (SOIs) between the eigenmodes in non-coupled PhC nanocavities and utilize them to obtain the intercavity interactions in passively coupled PhC nanocavity systems. With the help of coupling strength factors calculated from SOIs, we were able to fully exploit the coupled mode theory (CMT) and readily trace the detailed spectral behaviors of normal modes in various multi-coupled PhC nanocavities. Full-wave numerical simulation results verified the proposed method, revealing that the characteristics of original eigenmodes from non-coupled PhC nanocavities can act as key building blocks for analyzing the normal modes of multi-coupled PhC nanocavities. We further applied this SOI method to various multi-coupled PhC nanocavities with non-symmetric optical gain/loss distributions and successfully observed the unusual spectral evolution of normal modes and the correspondingly occurring unique non-Hermitian behaviors.
ABSTRACT
BACKGROUND: First rib resection is a surgical treatment for decompressing the neurovascular structures in thoracic outlet syndrome (TOS). Historically, extrathoracic approaches have used a posterior, supraclavicular, or transaxillary incision to remove the first rib. In this report, we demonstrate video-assisted thoracoscopic surgery for intrathoracic first rib resection (VATS-IFRR). METHODS: Between 2009 and 2014, eight patients underwent VATS-IFRR for TOS. Surgery was performed through two 5-mm ports and one 10-mm port. Endoscopic graspers, a hook-type electrocautery probe, a long peapod intervertebral disc rongeur, and Kerrison punches were used. The types of disease, operative times, chest tube indwelling days, lengths of hospital stay after operation, perioperative complications, postoperative pain scale ratings, and postoperative symptom recurrence rates at provocation tests were reviewed. The surgical outcomes were compared to published outcomes of extrathoracic approaches and other VATS approaches. RESULTS: The eight patients (3 right ribs, 5 left ribs) exhibited neurogenic (1 patient), combined type (2 patients), arterial (4 patients), and venous type (1 patient) TOS. The mean operative time was 190 (range 155-310) minutes. No mortalities or major complications occurred. The mean chest tube indwelling duration was 6 (range 3-10) days, and the mean postoperative hospital stay was 9 (range 4-21) days. The mean immediate postoperative pain numeric rating scale (NRS) score was 2.7/10 (range 2-4). No recurrence was observed during follow-up (median 25.5 months, range 10-64 months) in any patient. CONCLUSIONS: VATS-IFRR was safe and had several advantages. Thus, VATS-IFRR is a minimally invasive surgical option suitable for treating selective cases of TOS.