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1.
Sensors (Basel) ; 23(7)2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-37050434

RESUMEN

A significant innovation for future indoor wireless networks is the use of the mmWave frequency band. However, an important challenge comes from the restricted propagation conditions in this band, which necessitates the use of beamforming and associated beam management procedures, including, for instance, beam tracking or beam prediction. A possible solution to the beam management problem is to use artificial-intelligence-based procedures to learn the hidden spatial propagation patterns of the channel and to use this knowledge to predict the best beam directions. In this paper, we present a deep-neural-network-based method that has memory that can be used to predict the best reception directions for moving users. The best direction is the highest expected signal level at the next moment. The resulting method allows for a user-side antenna management system. The result was evaluated using three different metrics, thus detailing not only its predictive ability, but also its usability.

2.
Ann Noninvasive Electrocardiol ; 21(2): 161-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26105057

RESUMEN

BACKGROUND: In coronary artery disease (CAD), body surface potential mapping (BSPM) may reveal minor electrical potential changes appearing in the depolarization phase even if pathological changes are absent on the conventional 12-lead ECG. We hypothesized that a simple BSPM parameter, Max/Min signifies successful percutaneous coronary intervention (PCI). METHODS: Ninety-two adult Caucasian patients with stable CAD and positive exercise test underwent coronary angiography. Seventy patients (age, 59 ± 8; 46 males) were revascularized by PCI (left anterior descending [LAD] in 38, right [RCA] in 17 and left circumflex [LCX] coronary artery in 15). Control groups contained 22 patients (age, 60 ± 8; 14 males) without intervention and 35 healthy subjects (age, 58 ± 2; 15 males). Left ventricular ejection fraction (LVEF, transthoracic echocardiography) and Max/Min BSPM parameter (63-lead Montreal system) were evaluated before and 4-40 days following coronary angiography. Max/Min was defined by the ratio of the highest maximum to the deepest minimum potential of all leads recorded by BSPM. RESULTS: Before PCI, Max/Min value of patients with LAD lesion (0.83 [0.74; 0.93]) was significantly lower while that with RCA lesion (1.63 [1.35; 1.99]) was significantly higher than that of healthy group (1.01 [0.970; 1.13]) (P < 0.05) and LVEF was significantly lower in LAD lesion (46.50% [43.00; 51.00]) than in the healthy group (55.00% [50.00; 58.75]) (P < 0.01). Max/Min value significantly increased from 0.83 [0.74; 0.93] to 0.92 [0.82; 0.99] (P < 0.01) following LAD PCI while significantly decreased from 1.63 [1.35; 1.98] to 1.35 [1.21; 1.43] (P < 0.01) post-RCA PCI. It did not vary significantly, however, either following LCX PCI or without intervention. LVEF significantly increased (from 46.50% [43.00; 51.00] to 49.00% [46.00; 51.00]) only after LAD PCI. CONCLUSION: Max/Min parameter is suitable to follow patients after LAD and RCA PCI.


Asunto(s)
Mapeo del Potencial de Superficie Corporal/métodos , Mapeo del Potencial de Superficie Corporal/estadística & datos numéricos , Enfermedad de la Arteria Coronaria/cirugía , Intervención Coronaria Percutánea/métodos , Intervención Coronaria Percutánea/estadística & datos numéricos , Electrocardiografía/métodos , Electrocardiografía/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad
3.
ScientificWorldJournal ; 2014: 841680, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24558338

RESUMEN

This paper investigates filter bankmulticarrier (FBMC), a multicarrier modulation technique exhibiting an extremely low adjacent channel leakage ratio (ACLR) compared to conventional orthogonal frequency division multiplexing (OFDM) technique. The low ACLR of the transmitted FBMC signal makes it especially favorable in cognitive radio applications, where strict requirements are posed on out-of-band radiation. Large dynamic range resulting in high peak-to-average power ratio (PAPR) is characteristic of all sorts of multicarrier signals. The advantageous spectral properties of the high-PAPR FBMC signal are significantly degraded if nonlinearities are present in the transceiver chain. Spectral regrowth may appear, causing harmful interference in the neighboring frequency bands. This paper presents novel clipping based PAPR reduction techniques, evaluated and compared by simulations and measurements, with an emphasis on spectral aspects. The paper gives an overall comparison of PAPR reduction techniques, focusing on the reduction of the dynamic range of FBMC signals without increasing out-of-band radiation. An overview is presented on transmitter oriented techniques employing baseband clipping, which can maintain the system performance with a desired bit error rate (BER).


Asunto(s)
Simulación por Computador , Diseño de Equipo/métodos , Procesamiento de Señales Asistido por Computador , Telecomunicaciones , Simulación por Computador/normas , Diseño de Equipo/normas , Telecomunicaciones/normas
4.
J Clin Med ; 13(11)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38892910

RESUMEN

Background: Psoas muscle abscess (PMA) is an uncommon yet severe condition characterized by diagnostic and therapeutic challenges due to its varied etiology and nonspecific symptoms. This study aimed to evaluate the effectiveness and accuracy of various imaging techniques used in the image-guided percutaneous drainage (PD) of PMA. Methods: A systematic review was conducted following the PRISMA guidelines. We searched PubMed, Google Scholar, and Science Direct for studies published in English from 1998 onwards that reported on the use of PD in treating PMA, detailing outcomes and complications. Imaging modalities guiding PD were also examined. Results: We identified 1570 articles, selecting 39 for full review. Of these, 23 met the inclusion criteria; 19 were excluded due to unspecified PMA, absence of imaging guidance for PD, or inconclusive results. Eleven studies utilized computed tomography (CT) for PD, with six also using magnetic resonance imaging (MRI). Ten studies implemented ultrasound (US)-guided PD; variations in diagnostic imaging included combinations of US, CT, and MRI. A mixed approach using both CT and US was reported in two articles. Most studies using CT-guided PD showed complete success, while outcomes varied among those using US-guided PD. No studies employed MRI-guided PD. Conclusions: This review supports a multimodal approach for psoas abscess management, using MRI for diagnosis and CT for drainage guidance. We advocate for Cone Beam CT (CBCT)-MRI fusion techniques with navigation systems to enhance treatment precision and outcomes, particularly in complex cases with challenging abscess characteristics.

5.
Magy Onkol ; 67(4): 304-313, 2023 Dec 18.
Artículo en Húngaro | MEDLINE | ID: mdl-38109509

RESUMEN

Recent advances in molecular diagnostics are transforming the classification of malignant tumours, it has long played a major role in the field of CNS tumours. Examination of 1p/19q codeletion is indispensable in case of diffuse gliomas. Glioblastoma may be diagnosed even in the absence of characteristic morphological features, when EGFR amplification, TERT promoter mutation or +7/-10 copy number abnormalities are present. The number of entities defined by a genetic abnormality is growing. Comprehensive analysis of DNA methylation may be of considerable help in addition to histology and basic molecular studies, especially in case of small samples. Keeping up with the ever-expanding diagnostic repertoire is difficult, however, advantages and disadvantages of these methods and the context in which they may be useful should be understood by those who are involved in the diagnosis of CNS tumours. This summary provides a general overview of the main methods used in molecular diagnostics.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Sistema Nervioso Central , Glioma , Humanos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Patología Molecular , Neoplasias del Sistema Nervioso Central/genética , Glioma/genética , Aberraciones Cromosómicas , Isocitrato Deshidrogenasa/genética , Mutación
6.
Orv Hetil ; 160(24): 944-951, 2019 Jun.
Artículo en Húngaro | MEDLINE | ID: mdl-31433233

RESUMEN

Introduction: Plasma cell myeloma is a hematological malignancy with heterogeneous genomic landscape and diverse clinical course. Recurrent chromosomal and subchromosomal aberrations commonly occur in this entity and are associated with the pathogenesis and progression of the disease. The identification of these alterations aids genetic characterization, classification and prognostication of patients. Aim: Molecular cytogenetic investigations of plasma cell myeloma patients treated at the University of Pécs Clinical Center and János Balassa County Hospital of Tolna County, Szekszárd, between 2005 and 2018 were evaluated in our study. Method: 231 patients were screened for genetic aberrations using fluorescence in situ hybridization. Translocations involving the immunoglobulin heavy chain gene, losses of 1p and 17p chromosome arms, gains of 1q chromosome arm and unbalanced aberrations of chromosome 13 were investigated. Losses and gains of 1p, 1q, 5q, 12p, 13q, 16q and 17p chromosome arms were analyzed using multiplex ligation-dependent probe amplification in 42 patients. During the investigated period, 116 bone marrow karyotyping was also performed. Results: In total, 233 genetic aberrations were identified using our targeted approaches; the frequency of specific aberrations correlated with data of the recent literature. Concordance of results gained by fluorescence in situ hybridization and multiplex ligation-dependent probe amplification was 96.2% by analyzing the same chromosome arms. The latter technique revealed 21 additional genetic aberrations in 16/42 patient samples (38%) as compared to fluorescence in situ hybridization. Conclusions: Our results suggest that the combined application of the two molecular cytogenetic methods may facilitate a more detailed characterization of genetic aberrations of plasma cell myeloma patients in Hungary. Orv Hetil. 2019; 160(24): 944-951.


Asunto(s)
Aberraciones Cromosómicas , Análisis Citogenético/métodos , Mieloma Múltiple/genética , Humanos , Hungría/epidemiología , Hibridación Fluorescente in Situ , Mieloma Múltiple/epidemiología , Mieloma Múltiple/patología
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