Electromagnetic Wave Theory and Applications

Contains table of contents for Section 3, reports on four research projects and a list of publications.National Aeronautics and Space Administration Grant NAGW-1617National Aeronautics and Space Administration Agreement 958461National Aeronautics and Space Administration Grant NAGW-1272U.S. Army Corp of Engineers Contract DACA39-87-K-0022U.S. Navy - Office of Naval Research Grant N00014-89-J-1107U.S. Navy - Office of Naval Research Grant N00014-92-J-1616Digital Equipment CorporationJoint Services Electronics Program Contract DAAL03-92-C-0001U.S. Navy - Office of Naval Research Grant N00014-90-J-1002U.S. Navy - Office of Naval Research Grant N00014-89-J-1019U.S. Department of Transportation Agreement DTRS-57-88-C-00078TTD13U.S. Department of Transportation Agreement DTRS-57-88-C-00078TTD30U.S. Department of Transportation Agreement DTRS-57-92-C-00054TTD1DARPA/Consortium for Superconducting Electronics Contract MDA972-90-C-0021National Science Foundation Fellowship MIP 88-5876

Risk of acute myocardial infarction in patients with gastroesophageal reflux disease: A nationwide population-based study

Objective Gastroesophageal reflux disease (GERD) is a common disease which can cause troublesome symptoms and affect quality of life. In addition to esophageal complications, GERD may also be a risk factor for extra-esophageal complications. Both GERD and coronary artery disease (CAD) can cause chest pain and frequently co-exist. However, the association between GERD and acute myocardial infarction (AMI) remain unclear. The purpose of the study was to compare the incidence of acute myocardial infarction in GERD patients with an age-, gender-, and comorbidity matched population free of GERD. We also examine the association of the risk of AMI and the use of acid suppressing agents in GERD patients. Methods We identified patients with GERD from the Taiwan National Health Insurance Research Database. The study cohort comprised 54,422 newly diagnosed GERD patients; 269,572 randomly selected age-, gender-, comorbidity-matched subjects comprised the comparison cohort. Patients with any prior CAD, AMI or peripheral arterial disease were excluded. Incidence of new AMI was studied in both groups. Results A total 1,236 (0.5%) of the patients from the control group and 371 (0.7%) patients from the GERD group experienced AMI during a mean follow-up period of 3.3 years. Based on Cox proportional-hazard model analysis, GERD was independently associated with increased risk of developing AMI (hazard ratio (HR) = 1.48; 95% confidence interval (CI): 1.31–1.66, P < 0.001). Within the GERD group, patients who were prescribed proton pump inhibitors (PPIs) for more than one year had slightly decreased the risk of developing AMI, compared with those without taking PPIs (HR = 0.57; 95% CI: 0.31–1.04, P = 0.066). Conclusions This large population-based study demonstrates an association between GERD and future development of AMI, however, PPIs use only achieved marginal significance in reducing the occurrence of AMI in GERD patients. Further prospective studies are needed to evaluate whether anti-reflux medication may reduce the occurrence of acute ischemic event in GERD patients.Yeshttp://www.plosone.org/static/editorial#pee

Differences in the Control of Secondary Peristalsis in the Human Esophagus: Influence of the 5-HT4 Receptor versus the TRPV1 Receptor

Objective Acute administration of 5-hydroxytryptamine4 (5-HT4) receptor agonist, mosapride or esophageal infusion of the transient receptor potential vanilloid receptor-1 (TRPV1) agonist capsaicin promotes secondary peristalsis. We aimed to investigate whether acute esophageal instillation of capsaicin-containing red pepper sauce or administration of mosapride has different effects on the physiological characteristics of secondary peristalsis. Methods Secondary peristalsis was induced with mid-esophageal air injections in 14 healthy subjects. We compared the effects on secondary peristalsis subsequent to capsaicin-containing red pepper sauce (pure capsaicin, 0.84 mg) or 40 mg oral mosapride. Results The threshold volume for generating secondary peristalsis during slow air distensions was significantly decreased with capsaicin infusion compared to mosapride (11.6 ± 1.0 vs. 14.1 ± 0.8 mL, P = 0.02). The threshold volume required to produce secondary peristalsis during rapid air distension was also significantly decreased with capsaicin infusion (4.6 ± 0.5 vs. 5.2 ± 0.6 mL, P = 0.02). Secondary peristalsis was noted more frequently in response to rapid air distension after capsaicin infusion than mosapride (80% 60–100% vs. 65% 5–100%, P = 0.04). Infusion of capsaicin or mosapride administration didn’t change any parameters of primary or secondary peristalsis. Conclusions Esophageal infusion with capsaicin-containing red pepper sauce suspension does create greater mechanosensitivity as measured by secondary peristalsis than 5-HT4 receptor agonist mosapride. Capsaicin-sensitive afferents appear to be more involved in the sensory modulation of distension-induced secondary peristalsis.Yeshttp://www.plosone.org/static/editorial#pee

A Smart 3D RT Method: Indoor Radio Wave Propagation Modelling at 28 GHz

This paper describes a smart ray-tracing method based on the ray concept. From the literature review, we observed that there is still a research gap on conventional ray-tracing methods that is worthy of further investigation. The herein proposed smart 3D ray-tracing method offers an efficient and fast way to predict indoor radio propagation for supporting future generation networks. The simulation data was verified by measurements. This method is advantageous for developing new ray-tracing algorithms and simulators to improve propagation prediction accuracy and computational speed

An efficient 3-D ray tracing method: prediction of indoor radio propagation at 28 GHz in 5G network

Millimeter wave technology will be dominating the fifth-generation networks due to the clear advantage of higher frequency bands and hence wider spectrum. In this paper, the indoor radio wave propagation at 28 GHz is studied by developing an efficient three-dimensional ray tracing (ETRT) method. The simulation software based on the ETRT model has been verified by measurement data. The received signal strength indication and path loss have shown significant agreement between simulation and measurement. Compared with the conventional shooting bouncing ray tracing method, the proposed ETRT method has better agreement with measurement data

Review of Indoor Positioning: Radio Wave Technology

The indoor positioning system (IPS) is becoming increasing important in accurately determining the locations of objects by the utilization of micro-electro-mechanical-systems (MEMS) involving smartphone sensors, embedded sources, mapping localizations, and wireless communication networks. Generally, a global positioning system (GPS) may not be effective in servicing the reality of a complex indoor environment, due to the limitations of the line-of-sight (LoS) path from the satellite. Different techniques have been used in indoor localization services (ILSs) in order to solve particular issues, such as multipath environments, the energy inefficiency of long-term battery usage, intensive labour and the resources of offline information collection and the estimation of accumulated positioning errors. Moreover, advanced algorithms, machine learning, and valuable algorithms have given rise to effective ways in determining indoor locations. This paper presents a comprehensive review on the positioning algorithms for indoors, based on advances reported in radio wave, infrared, visible light, sound, and magnetic field technologies. The traditional ranging parameters in addition to advanced parameters such as channel state information (CSI), reference signal received power (RSRP), and reference signal received quality (RSRQ) are also presented for distance estimation in localization systems. In summary, the recent advanced algorithms can offer precise positioning behaviour for an unknown environment in indoor locations