RESUMO
Frequency lock-in-induced deadband phenomena are major problems of ring laser gyroscopes (RLGs), which deteriorate linear responses to changes in the applied rotation rate. In this work, the frequency lock-in phenomenon occurring in the RLG was successfully investigated by compensating for the Sagnac effect through frequency analysis using a newly defined error function. Integrative and generalized viewpoints from the analyzed results provide new possibilities for relevant performance improvements of optical gyroscopes, as well as a deeper understanding of locked states in principle aspects.
RESUMO
The relationships between the microstructure and the dielectric properties of sol-gel prepared Y2O3 films with various Gd3+ doping were systematically investigated. Robust solution processed lanthanide films, (Y1-xGdx)2O3 (0 < x ≤ 0.5), are demonstrated as high-k gate insulators for low voltage-driven oxide thin film transistors and their optimized composition is presented. With the proper amount of Gd3+ doping, the corresponding thin film insulators exhibit low leakage current with increased dielectric constant. The resultant Zn-Sn-O/(Y, Gd)2O3 TFT exhibits enhanced performance, by a factor of 10.7 compared with TFTs using a SiO2 insulator, with a field-effect mobility of ~3.15 cm²V-1s-1 and an exceptionally low operating voltage <15 V.
RESUMO
PURPOSE: In patients with independent mobility, full hip range of motion and sufficient muscle strength for daily life without cognitive impairment, treatment of a femoral neck fracture with total hip arthroplasty (THA) may be a better option compared to bipolar hip hemiarthroplasty. Here, functional outcomes and complications in patients who underwent THA for femoral neck fracture based on their comorbidity status were analyzed. MATERIALS AND METHODS: Between January 2013 and December 2018, 110 patients were treated with THA for femoral neck fractures at our institution. These patients were retrospectively analyzed for clinical outcomes at final follow-up (mean=24.4 months, range: 6-81 months) using the Harris hip score (HHS) and the presence or absence of two potential comorbidities: i) diabetes mellitus (DM; 35 with and 75 without) and ii) hypertension (HTN; 50 with and 60 without). RESULTS: The incidence of superficial infections at the surgical site in patients with DM was significantly higher compared with patients without DM (P=0.024). There were no significant differences in other potential complications based on DM status. HHS at final follow-up between patients with and without DM and with and without HTN were not significantly different (83.3 vs. 81.0, P=0.39 and 81.6 vs. 82.4, P=0.75, respectively). CONCLUSION: Superficial infections occurred more frequently in patients with DM compared with patients without DM. DM and HTN status are not correlated with HHS.
RESUMO
BACKGROUND: The Korean Shoulder Scoring System (KSS) is a reliable and valid procedure for discriminative assessment of the clinical status of patients with rotator cuff tears. This study evaluates the correlation between the preoperative KSS and factors in patients with rotator cuff tears. METHODS: From November 2009 to June 2016, 970 patients who underwent arthroscopic rotator cuff repair were retrospectively evaluated. A total of 490 patients met the study criteria. Preoperative factors included age, sex, symptom duration, mediolateral (ML) and anteroposterior (AP) tear size, acromiohumeral distance (AHD), tangent sign, tendon involvement (type I, supraspinatus; type II, supraspinatus and subscapularis; type III, supraspinatus and infraspinatus; type IV, all 3 tendons), fatty infiltration of rotator cuff muscles (group I, Goutallier stages 0 and 1; group II, Goutallier stages 2, 3, and 4), and KSS. RESULTS: Old age, ML tear size, and AP tear size negatively correlated with the preoperative KSS (p<0.001). AHD showed a positive correlation with the preoperative KSS (p<0.001). A significantly inferior preoperative KSS was found in females and type III tendon involvement (p<0.001). For supraspinatus and infraspinatus, the preoperative KSS of group II fatty infiltration showed a significantly lower score than group I fatty infiltration (p<0.05). CONCLUSIONS: A relatively lower preoperative KSS was associated with old age, large tear size, narrow AHD, female, type III tendon involvement, and group II fatty infiltration of the supraspinatus and infraspinatus. Our study indicates that preoperative KSS can be a good measurement for the preoperative status of patients with rotator cuff tears.
RESUMO
PURPOSE: We compared adductor canal block (ACB) alone and a combination of ACB and sciatic nerve block (SNB) to control early postoperative pain after total knee arthroplasty. MATERIALS AND METHODS: One hundred patients received continuous ACB alone (group A), and another 100 patients received continuous ACB and single popliteal SNB (group B). Pain was evaluated at rest and 45° knee flexion using the numeric rating scale (NRS). The number of times the patient pressed the intravenous patient-controlled analgesia (PCA) button, total PCA volume infused, and the total dosage of additional analgesics were evaluated. We also investigated complications associated with each pain control technique. RESULTS: The NRS score on postoperative day 1 was significantly lower in group B than in group A. The number of times patients pressed the PCA button on postoperative day 1 and the total infused volume were significantly lower in group B than in group A. Thirty-five (35%) patients in group B developed foot drop immediately after surgery; but they all fully recovered on postoperative day 1. CONCLUSIONS: SNB can be effective for management of early postoperative pain that persists even after ACB. Further research is needed to determine the proper dosage and technique for reducing the incidence of foot drop.
RESUMO
Popliteal artery compression rarely occurs after posterior cruciate ligament (PCL) reconstruction using the tibial inlay technique that allows for direct visualization of the surgical field. However, we experienced a popliteal artery compression after PCL reconstruction performed using the technique, which eventually required re-operation. Here, we report this rare case and discuss reasons of popliteal artery compression.