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We present a general approach for antenna design and optimization based on consensus of results from a number of independently trained deep neural networks (DNNs). The aim of using the consensus is to reduce the uncertainty of results from a single DNN. The approach leads to several orders of magnitude faster antenna optimization and design compared to the optimization based on a full-wave solver and allows a compromise between the analysis speed and its accuracy. The used DNNs are multilayer perceptrons (MLP) with multiple fully connected hidden layers. As an example, we consider the Yagi–Uda antenna with four design parameters and optimize it for the maximal forward gain. The training of neural networks is done on datasets of several sizes, up to 1 million antenna samples. The samples are generated either randomly or at a uniform grid over the design space using the method of moments. [ABSTRACT FROM AUTHOR]

Paediatric and Adolescent Gynaecology (PAG) is a subspecialty under the umbrella of Obstetrics and Gynaecology but linked to other branches of medicine including Paediatrics, Surgery, Endocrinology and Urology. Therefore future developments in clinical care and education requires a multidisciplinary approach combining aspects of all the above medical specialties, and also with inputs from Public Health, Genetics, Radiology and Psychology. A multidisciplinary collaboration among different specialists is as important as the establishment and adoption of standards in education, training and management. PAG in Europe has evolved from its first steps and it is still growing with the aim of providing increasing protection of the gynaecological and reproductive health of female children and adolescents. In fact, without proper advice and care, inappropriate management of gynaecological issues in childhood and adolescence can be expected to have significant repercussions throughout later years, and into adulthood. The aim of this third paper in this mini-symposium is to explore how PAG should develop in Europe in the near future. [ABSTRACT FROM AUTHOR]

This article proposes a neural network-based approach to increase accuracy of two-dimensional direction of arrival (DOA) estimation of an electromagnetic signal. The proposed method combines two neural networks developed using simulated and small amount of empirical data, respectively. The output of the simulation-based neural network represents approximate information on DOAs. It is then considered as a priori knowledge for the small empirical network that is crucial for obtaining more accurate DOA estimates. The developed cascade-connected model is validated using real data from a rectangular antenna array. Improvements in terms of accuracy and reliability are obtained and compared with the MUSIC algorithm. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives: To assess changes in portal and splanchnic arterial haemodynamics in patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) using four-dimensional (4D) flow MRI, a non-invasive, non-contrast imaging technique. Methods: Eleven patients undergoing TIPS implantation were enrolled. K-t GRAPPA accelerated non-contrast 4D flow MRI of the liver vasculature was applied with acceleration factor R = 5 at 3Tesla. Flow analysis included three-dimensional (3D) blood flow visualization using time-resolved 3D particle traces and semi-quantitative flow pattern grading. Quantitative evaluation entailed peak velocities and net flows throughout the arterial and portal venous (PV) systems. MRI measurements were taken within 24 h before and 4 weeks after TIPS placement. Results: Three-dimensional flow visualization with 4D flow MRI revealed good image quality with minor limitations in PV flow. Quantitative analysis revealed a significant increase in PV flow (562 ± 373 ml/min before vs. 1831 ± 965 ml/min after TIPS), in the hepatic artery (176 ± 132 ml/min vs. 354 ± 140 ml/min) and combined flow in splenic and superior mesenteric arteries (770 ml/min vs. 1064 ml/min). Shunt-flow assessment demonstrated stenoses in two patients confirmed and treated at TIPS revision. Conclusions: Four-dimensional flow MRI might have the potential to give new information about the effect of TIPS placement on hepatic perfusion. It may explain some unexpected findings in clinical observation studies. Key Points: • 4D flow MRI, a non-invasive, non-contrast imaging technique, is feasible after TIPS. • Provides visualization and quantification of hepatic arterial, portal venous, collateral and TIPS haemodynamics. • Better understanding of liver blood flow changes after TIPS and patient management. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents development and validation of an artificial neural network (ANN)-based model for accurate two-dimensional direction of arrival estimation of two coherent sources. The ANN model is developed using simulated signals and its performance is evaluated by measurements inside an anechoic chamber. Simulations and experiments show good agreement in estimating both azimuth and elevation angles of coherent sources. The proposed model demonstrates ability to separate two closely spaced sources and outperforms MUSIC with spatial smoothing preprocessing in the case of small number of signal snapshots. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2558-2562, 2014 [ABSTRACT FROM AUTHOR]

The article discusses the importance of four-dimensional (4D) magnetic resonance imaging (MRI) flow imaging in controlling transjugular intrahepatic portosystemic shunt (TIPS) function. It describes the case of a 50-year-old woman with alcohol-induced Child-Pugh B liver cirrhosis. It suggests that 4D MRI allows complete volumetric coverage with access to the stent lumen in patients after covered TIPS stent graft implantation.

Purpose: To evaluate short- and long-term effects of structured exercise program in euthyroid patients with Graves' disease. Methods: The study employed a retrospective case-control design. The exercise group (n = 62) underwent 3 weeks of structured exercise program consisting of daily walking, strengthening, and stretching exercises while the control group (n = 62) participated in leisure activities. Thyroid profile, aerobic capacity, and perceived fatigue were evaluated on in-patient admission and discharge. Time to discontinuation of anti-thyroid medication after discharge and time to relapse of symptoms were determined. Results: The exercise group increased estimated peak oxygen consumption (significant group-by-time ANOVA interaction, P < 0.001), decreased serum thyroxin (P = 0.038), increased serum thyrotropin (P = 0.071), and reported less fatigue (Fisher's exact test, p < 0.001) from admission to discharge. The anti-thyroid medication was withdrawn within 6 months of discharge in significantly greater proportion of subjects in the exercise than control group (84% vs. 18%). Conversely, the rate of relapse within 12 months of medication withdrawal was smaller in the exercise (29%) than control group (72%). Conclusions: The results suggest that structured exercise program may normalize thyroid profile, improve aerobic capacity, and reduce fatigue on the short-term basis as well as reduce the need for anti-thyroid medication on the long-term basis. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to investigate 3D flow patterns and vessel wall parameters in patients with dilated ascending aorta, age-matched subjects, and healthy volunteers. Methods: Thoracic time-resolved 3D phase contrast CMR with 3-directional velocity encoding was applied to 33patients with dilated ascending aorta (diameter ≥40 mm, age=60±16 years), 15 age-matched normal controls (diameter ≤37 mm, age=68±7.5 years) and 15 young healthy volunteers (diameter ≤30 mm, age=23±2 years). 3D blood flow was visualized and flow patterns were graded regarding presence of supra-physiologic-helix and vortex flow using a semi-quantitative 3-point grading scale. Blood flow velocities, regional wall shear stress (WSS), and oscillatory shear index (OSI) were quantified. Results: Incidence and strength of supra-physiologic-helix and vortex flow in the ascending aorta (AAo) was significantly higher in patients with dilated AAo (16/33 and 31/33, grade 0.9±1.0 and 1.5±0.6) than in controls (2/15 and 7/15, grade 0.2 ± 0.6 and 0.6 ± 0.7, P<.05) or healthy volunteers (1/15 and 0/15, grade 0.1 ± 0.3 P<.05). Greater strength of the ascending aortic helix and vortex flow were associated with significant differences in AAo diameters (P<.05). Peak systolic WSS in the ascending aorta and aortic arch was significantly lower in patients with dilated AAo (P<.0157-.0488). AAo diameter positively correlated to time to peak systolic velocities (r=0.30-0.53, P<.04), OSI (r=0.33-0.49, P<0.02) and inversely correlated to peak systolic WSS (r=0.32-0.40, P<.03). Peak systolic WSS was significantly lower in AAo aneurysms at the right and outer curvature within the AAo and proximal arch (P<.01-.05). Conclusions: Increase in AAo diameter is significantly correlated with the presence and strength of supra-physiologic-helix and vortex formation in the AAo, as well with decrease in systolic WSS and increase in OSI. [ABSTRACT FROM AUTHOR]

Introduction: Auron Misheil Therapy was developed based on similarities between carcinogenesis and inflammation. Auron Misheil Therapy is a combination of natural and synthetic compounds, including anti-inflammatory drugs and insulin, expected to exhibit synergistic effects.Case Presentation: Here, we report the case of a 78-year-old Caucasian male patient who presented with multifocal hepatocellular carcinoma and chronic hepatitis C virus infection. Over a four-year period our patient was treated with radiofrequency ablation and transarterial chemoembolization. After these treatments there was tumor progression, with new hyperperfused lesions without evidence of extrahepatic tumor involvement. Our patient refused sorafenib therapy. Therefore, he received twice daily intramuscular injections of Auron Misheil Therapy on an outpatient basis for two months. Partial remission of the hepatic lesions was observed eight weeks after the start of treatment, and confirmed four weeks later. Unfortunately, at that time our patient refused therapy due to dizziness. During follow-up two target lesions remained stable, but one lesion increased in size. At the latest follow-up, one year later, there was still tumor control.Conclusion: While the mechanisms underlying the antitumor effects of Auron Misheil Therapy are not fully understood, stable disease and remissions have been observed in different types of tumors, including hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

To assess the role of fluid aspiration in ovarian preservation from a great anechoic cystic adnexal mass. In addition, the diagnostic value of fluid levels of estradiol and CA 125 were examined. A prospective longitudinal study using clinical and ultrasound data collected for all patients under 19 years of age with clear cystic adnexal masses and ultrasonographic presence of the ipsilateral normal ovarian tissue, or the ovarian crescent sign (OCS) as a predictor of benign origin, with volume ≥200 ml, managed between January 2006 and November 2022. Aspiration was performed before surgery with the aim of strengthening the normal ovarian tissue to be whole preserved during laparoscopic stripping. In patients with suspicious for torsion samples was taken during laparoscopy. Pediatric and Adolescent Gynecology Departments in hospitals in three European countries. Surgical treated 92 patients with anechoic cystic adnexal masses. Ovarian volume, the presence of OCS and anechoic content were reported. From first syringe, fluid level of estradiol in pg/l and CA 125 in IU/ml were measured and correlated with postoperative histologic findings. The median cyst volume was 570 ml (range between 200 and 7600 ml). The normal ovarian tissue was reported, and no malignancy was found in all of 92 patients laparoscopically treated. Paraovarian cysts was considered on ultrasonography in 39 patients, but in four of them intrafilamentary ovarian cystadenomas was confirmed during laparoscopy. With laparoscopic stripping, the whole ovaries were preserved in nine patients with cystic mature teratomas and in 42 patients with serous cystadenomas including largest of 7600 ml. Torsion was reported in three of previous mentioned paraovarian cysts and in six ovarian cystic masses. Fluid levels of estradiol and CA 125 were successfully measured in all cystic masses except two ovarian torsions. CA 125 was significantly elevated in all serous cystadenomas and paraovarian cysts, Table 1, but estradiol was elevated only in four of functional ovarian cysts. In all large cystic mature teratomas both fluid markers remained low. Ovarian volume recovered to normal value within three months, as previous reported. ▪ Aspiration of cyst fluid before surgery in clearly defined patients may be very helpful to insuring ovarian tissue preservation in large cystic masses. Fluid levels of estradiol and CA 125 correlate with histology diagnosis and can be useful in distinguishing functional cysts from serous cystadenomas and paraovarian cyst, and cystic mature teratomas. [ABSTRACT FROM AUTHOR]

Background: Over the last decades, time domain heart rate (HR) variability analysis has been explored in different pediatric clinical settings to obtain information on the cardiac autonomic tone. However, the consistency over time of 24 h time domain HRV measurements in children is not well-known. Methods: We investigated the reproducibility of 24 h HRV time-domain indices (1 day apart), from 39 healthy children (9.5 ± 5.3 years, 56.4% girls). The parameters analysed included: standard deviation of all the adjacent NN intervals, standard deviation of the averages of NN intervals (the intervals between normal R-peaks) in all 5-min segments, and square root of the mean of the sum of the squares of the differences between adjacent NN intervals, uncorrected and corrected for HR. Reproducibility between two 24-h ECG recordings was evaluated by intraclass correlation coefficients, standard error of measurement, coefficients of variation and Bland-Altman plots. Results: For the analyzed time-domain indices, standard deviation of all the adjacent NN intervals corrected for HR showed best reproducibility with the highest intraclass correlation coefficient (0.987), the lowest coefficients of variation (5.5%) and the best level of agreement between two recordings as assessed by Bland-Altman plots. Conclusions: Our results indicate that the standard deviation of all the adjacent NN intervals corrected for the HR parameter obtained from 24-h ambulatory recordings in children is consistent and reproducible over time, thus allowing reliable identification of cardiac autonomic tone in this age group. [ABSTRACT FROM AUTHOR]

Background Thoracic and abdominal 4D flow MRI is typically acquired in combination with navigator respiration control which can result in highly variable scan efficiency (S eff ) and thus total scan time due to inter-individual variability in breathing patterns. The aim of this study was to test the feasibility of an improved respiratory control strategy based on diaphragm navigator gating with fixed S eff , respiratory driven phase encoding, and a navigator training phase. Methods 4D flow MRI of the thoracic aorta was performed in 10 healthy subjects at 1.5 T and 3 T systems for the in-vivo assessment of aortic time-resolved 3D blood flow velocities. For each subject, four 4D flow scans (1: conventional navigator gating, 2–4: new implementation with fixed S eff = 60%, 80% and 100%) were acquired. Data analysis included semi-quantitative evaluation of image quality of the 4D flow magnitude images (image quality grading on a four point scale), 3D segmentation of the thoracic aorta, and voxel-by-voxel comparisons of systolic 3D flow velocity vector fields between scans. Results Conventional navigator gating resulted in variable S eff = 74 ± 13% (range = 56%–100%) due to inter-individual variability of respiration patterns. For scans 2–4, the new navigator implementation was able to achieve predictable total scan times with stable S eff, only depending on heart rate. Semi- and fully quantitative analysis of image quality in 4D flow magnitude images was similar for the new navigator scheme compared to conventional navigator gating. For aortic systolic 3D velocities, good agreement was found between all new navigator settings (scan 2–4) with the conventional navigator gating (scan 1) with best performance for S eff = 80% (mean difference = − 0.01 m/s; limits of agreement = 0.23 m/s, Pearson's ρ = 0.89, p < 0.001). No significant differences for image quality or 3D systolic velocities were found for 1.5 T compared to 3 T. Conclusions The findings of this study demonstrate the feasibility of the new navigator scheme to acquire 4D flow data with more predictable scan time while maintaining image quality and 3D velocity information, which may prove beneficial for clinical applications. [ABSTRACT FROM AUTHOR]

In order to provide a constant and complete operational picture of the maritime situation in the Exclusive Economic Zone (EEZ) at over the horizon (OTH) distances, a network of high frequency surface-wave-radars (HFSWR) slowly becomes a necessity. Since each HFSWR in the network tracks all the targets it detects independently of other radars in the network, there will be situations where multiple tracks are formed for a single vessel. The algorithm proposed in this paper utilizes radar tracks obtained from individual HFSWRs which are already processed by the multi-target tracking algorithm at the single radar level, and fuses them into a unique data stream. In this way, the data obtained from multiple HFSWRs originating from the very same target are weighted and combined into a single track. Moreover, the weighting approach significantly reduces inaccuracy. The algorithm is designed, implemented, and tested in a real working environment. The testing environment is located in the Gulf of Guinea and includes a network of two HFSWRs. In order to validate the algorithm outputs, the position of the vessels was calculated by the algorithm and compared with the positions obtained from several coastal sites, with LAIS receivers and SAIS data provided by a SAIS provider. [ABSTRACT FROM AUTHOR]