A compact and low-profile tunable loop antenna integrated with inductors

We present a frequency-tunable, compact loop antenna which consists of a transmission line on a ground plane, two shorting posts, and two inductors which are serially connected between the posts and the edge of the transmission line. By properly choosing the inductance of the inductors, the operating frequency of the antenna can be controlled without seriously sacrificing fractional bandwidth. To demonstrate the operating mechanism, the equivalent circuit of this antenna is included. The characteristics of the antenna with various inductors integrated are also investigated. Fabricated antennas show that the operating frequency can be shifted from 2.07 GHz to 1.2 GHz using off-the-shelf inductors. Using two 33-nH inductors achieves an antenna with an electrical size as small as 0.118lambda times 0.013lambda times 0.047lambda. The validity of this antenna is demonstrated by experimental results

Compact and low-profile frequency agile loop antenna integrated with inductors

We present a frequency agile loop antenna which consists of a suspended transmission line and two inductors. Using appropriate inductors, the operating frequency of the antenna can be controlled without seriously sacrificing its performance. We derived an equivalent circuit of this proposed compact and low-profile antenna. Results from some prototypes showed that a frequency tuning range as high as 870 MHz can be achieved using off-the shelf inductors. In the case of integrating two inductors of 33 nH, an electrical size of the antenna as small as 0.118 λ × 0.013 λ × 0.047 λ is achieved

Recurrent Catecholamine-Induced Cardiomyopathy in a Patient With a Pheochromocytoma

Pheochromocytomas presents with variable clinical manifestations. Cardiomyopathy caused by a pheochromocytoma is well known. We report the case of a 62-year-old woman with recurrent left ventricular dysfunction, who was subsequently found to have a pheochromocytoma. The patient had two different patterns of cardiomyopathy. Patients with a cardiomyopathy, of non-specific origin, should have a pheochromocytoma ruled out

Complications of 2-D Echocardiography Guided Transfemoral Right Ventricular Endomyocardial Biopsy

Endomyocardial biopsy (EMBx) is a useful tool for diagnosing various cardiac pathologies. However, the routine use of EMBx has not gained widespread acceptance due to the possible complications related to the EMBx. Thus, not much information is available on the complications related to the EMBx. We prospectively evaluated 90 consecutive patients who underwent 2-D echocardiography guided transfemoral right ventricular EMBx at Kyungpook National University Hospital between March 2002 and November 2005 to determine the incidence, nature and subsequent management of complications related to EMBx. The clinical diagnoses before the EMBx were arrhythmogenic right ventricular dysplasia in 54, dilated cardiomyopathy in 19, Brugada syndrome in 9, myocarditis in 6 and miscellaneous in 2 patients. The overall major complication rate was 5.6% and no procedure-related mortality occurred. Myocardial perforation (n=3), which was the most frequent complication, did not progress to cardiac tamponade requiring pericardiocentesis in any patient. Hemodynamically unstable ventricular tachycardia occurred in 1 patient. New and persistent right bundle branch block occurred in another. Our findings suggest that 2-D echocardiography guided transfemoral right ventricular EMBx is a relatively safe procedure

Survival impact of additional chemotherapy after adjuvant concurrent chemoradiation in patients with early cervical cancer who underwent radical hysterectomy

Background To determine whether additional chemotherapy after concurrent chemoradiation (CCRT) improves survival outcomes in patients with early cervical cancer who undergo radical hysterectomy (RH). Methods We included high- or intermediate-risk patients from two institutions, with 2009 FIGO stage IB–IIA, who underwent primary RH and pelvic lymphadenectomy between January 2007 and June 2020, and had completed adjuvant CCRT. Survival outcomes were compared between patients who received additional chemotherapy (study group) and those who did not (control group). Results A total of 198 patients were included in this analysis. The study (n = 61) and control groups (n = 137) had similar patient age, histologic cancer type, 2009 FIGO stage, and tumor size. However, minimally invasive surgery was performed less frequently in the study group than in the control group (19.7% vs. 46.0%, P < 0.001). The presence of pathologic risk factors was similar, except for lymph node metastasis, which was more frequent in the study group (72.1% vs. 46.0%; P = 0.001). In survival analyses, no differences in the disease-free survival (DFS; P = 0.539) and overall survival (OS; P = 0.121) were observed between the groups. Multivariate analyses adjusting for surgical approach and other factors revealed that additional chemotherapy was not associated with DFS (adjusted HR, 1.149; 95% CI, 0.552–2.391; P = 0.710) and OS (adjusted HR, 1.877; 95% CI, 0.621–5.673; P = 0.264). The recurrence patterns did not differ with additional chemotherapy. Consistent results were observed in a subset of high-risk patients (n = 139). Conclusions Additional chemotherapy after CCRT might not improve survival outcomes in patients with early cervical cancer who undergo RH.This work was supported by the Korea Medical Device Development Fund grants funded by the Korea government: the Ministry of Trade, Industry and Energy (Project Number: 9991007086) and the Ministry of Science and ICT (Project Number: 9991007274)