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1.
Microsyst Nanoeng ; 8: 28, 2022.
Article in English | MEDLINE | ID: mdl-35310512

ABSTRACT

Radiofrequency identification (RFID), particularly passive RFID, is extensively employed in industrial applications to track and trace products, assets, and material flows. The ongoing trend toward increasingly miniaturized RFID sensor tags is likely to continue as technology advances, although miniaturization presents a challenge with regard to the communication coverage area. Recently, efforts in applying metamaterials in RFID technology to increase power transfer efficiency through their unique capacity for electromagnetic wave manipulation have been reported. In particular, metamaterials are being increasingly applied in far-field RFID system applications. Here, we report the development of a magnetic metamaterial and local field enhancement package enabling a marked boost in near-field magnetic strength, ultimately yielding a dramatic increase in the power transfer efficiency between reader and tag antennas. The application of the proposed magnetic metamaterial and local field enhancement package to near-field RFID technology, by offering high power transfer efficiency and a larger communication coverage area, yields new opportunities in the rapidly emerging Internet of Things (IoT) era.

2.
Commun Phys ; 2(1)2019 Dec.
Article in English | MEDLINE | ID: mdl-31673637

ABSTRACT

Magnetic resonance imaging (MRI) represents a mainstay among the diagnostic imaging tools in modern healthcare. Signal-to-noise ratio (SNR) represents a fundamental performance metric of MRI, the improvement of which may be translated into increased image resolution or decreased scan time. Recently, efforts towards the application of metamaterials in MRI have reported improvements in SNR through their capacity to interact with electromagnetic radiation. While promising, the reported applications of metamaterials to MRI remain impractical and fail to realize the full potential of these unique materials. Here, we report the development of a magnetic metamaterial enabling a marked boost in radio frequency field strength, ultimately yielding a dramatic increase in the SNR (~ 4.2X) of MRI. The application of the reported magnetic metamaterials in MRI has the potential for rapid clinical translation, offering marked enhancements in SNR, image resolution, and scan efficiency, thereby leading to an evolution of this diagnostic tool.

3.
Heart Rhythm ; 8(10): 1555-9, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21699835

ABSTRACT

BACKGROUND: Large-scale electrocardiographic (ECG) screening of young athletes has been shown to reduce the incidence of sudden cardiac death in Italy. Debate exists regarding the feasibility and benefits of such a program in the United States. OBJECTIVE: The purpose of this study was to describe implementation and results of a large-scale high school ECG screening program (Young Hearts for Life [YH4L]) developed in the Chicago area. METHODS: A retrospective cohort study of 32,561 high school students from 38 ECG screenings was performed between September 2006 and May 2009. Screenings were performed by the YH4L program, which consisted of a core group of administrators, cardiologists, and community volunteers who underwent specialized training and quality review. The rates of abnormal ECGs requiring further evaluation and unacceptable ECGs due to poor quality were determined. RESULTS: Of the 32,561 students screened, 817 (2.5%) had abnormal ECGs requiring further evaluation. The majority of abnormal ECGs occurred in males (66%). Only 0.81% of ECGs were determined to be technically inadequate, requiring repeat ECGs on the same day of the screening. The prevalence of left ventricular hypertrophy and abnormal ST-T wave changes was lower in our study than in the rates reported in an Italian registry, possibly due to the lower frequency of men and highly trained athletes in our study. CONCLUSION: Large-scale ECG screening of U.S. high school students is feasible and identifies ECGs requiring further evaluation in 2.5% of individuals. These findings have implications for implementing screening and preventing sudden cardiac death in U.S. youth.


Subject(s)
Electrocardiography , Heart Diseases/diagnosis , Mass Screening , Adolescent , Chi-Square Distribution , Chicago/epidemiology , Feasibility Studies , Female , Heart Diseases/epidemiology , Humans , Incidence , Male , Prevalence , Retrospective Studies , Students , Young Adult
4.
Emerg Radiol ; 17(1): 21-9, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19381700

ABSTRACT

Computed tomography (CT) has been shown to be increasingly useful in the evaluation of blunt trauma patients with suspected abdominopelvic vascular injuries. CT findings of abdominopelvic vascular insult may be broadly characterized as end-organ abnormalities or direct evidence of vascular injury. End-organ abnormalities implying an underlying vascular insult include identifying an area of relative hypoperfusion in solid organ injury. Direct evidence of a vascular injury includes identifying an irregular or thrombosed vessel or an area of active hemorrhage, among other findings. This review article aims to review and illustrate these findings of blunt abdominopelvic vascular trauma. Also, evolving lessons from our level I trauma center in the use of multiphasic imaging to further characterize sources of a vascular blush and the differentiation of arterial from venous sources of active hemorrhage are discussed.


Subject(s)
Abdominal Injuries/diagnostic imaging , Blood Vessels/injuries , Pelvis/injuries , Tomography, X-Ray Computed/methods , Wounds, Nonpenetrating/diagnostic imaging , Humans , Pelvis/blood supply
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