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This study introduces a novel metamaterial absorber operating in X-band frequency range, characterized by two resonating peaks. The proposed structure consist of four circular sectors connected by two cross resonators enclosed by a circular strip with the dielectric between them. FR4 is used as a substrate backed by a copper ground plane. Simulation results reveal that the reflection co-efficient remains consistently below -10dB across the entire X-band, ensuring effective absorption of incident electromagnetic waves. Moreover, the absorber achieves 100% absorptivity with the gain of -25dB under normal incidence. The validity of absorber performance is confirmed through impedance plot and Voltage Stand Waving Ration (VSWR) analysis, verifying the accuracy of S11 parameter. Furthermore, the proposed structure has a compact size of 0.1666 λ. The absorber’s robust performance validated through numerical analysis, positions it as a compelling candidate for various X-band applications, including radar systems, communication devices, and stealth technology. This research establishes the proposed metamaterial absorber as a promising solution for X-band electromagnetic wave attenuation needs, offering both superior performance and compact design.

The cyclic loading of foundation structures in sand leads to an accumulation of plastic deformations in the structures. For shallow foundations of high and slender structures such as wind energy converters (WECs), an accumulation of the plastic rotations is expected under cyclic eccentric loading that is imposed by wind loads, which could be crucial for the proof of serviceability. A practical approach to predict the behavior of shallow foundations under high-cycle eccentric loading is under research. In this paper, a numerical approach, the cyclic strain accumulation method (CSAM), which has been validated for cyclically loaded monopiles, is adopted for shallow foundations under eccentric cyclic loading. Modifications to the CSAM are described, which are necessary to apply it to shallow foundations. The results that are gained with the modified method are compared with a medium-scale model test, in which the deformations of a footing with a diameter of 2.0 m under eccentric one-way cyclic loading were investigated. It can be concluded that the CSAM can make realistic predictions and shows satisfying agreement with the measured cyclic behavior. Although more experiments are needed to finally validate the method, the CSAM could be a promising numerical approach to account for the cyclic behavior of shallow foundations under eccentric cyclic loading in sand. [ABSTRACT FROM AUTHOR]

(1) Background: Colon polyps are common protrusions in the colon’s lumen, with potential risks of developing colorectal cancer. Early detection and intervention of these polyps are vital for reducing colorectal cancer incidence and mortality rates. This research aims to evaluate and compare the performance of three machine learning image classification models’ performance in detecting and classifying colon polyps. (2) Methods: The performance of three machine learning image classification models, Google Teachable Machine (GTM), Roboflow3 (RF3), and You Only Look Once version 8 (YOLOv8n), in the detection and classification of colon polyps was evaluated using the testing split for each model. The external validity of the test was analyzed using 90 images that were not used to test, train, or validate the model. The study used a dataset of colonoscopy images of normal colon, polyps, and resected polyps. The study assessed the models’ ability to correctly classify the images into their respective classes using precision, recall, and F1 score generated from confusion matrix analysis and performance graphs. (3) Results: All three models successfully distinguished between normal colon, polyps, and resected polyps in colonoscopy images. GTM achieved the highest accuracies: 0.99, with consistent precision, recall, and F1 scores of 1.00 for the ‘normal’ class, 0.97–1.00 for ‘polyps’, and 0.97–1.00 for ‘resected polyps’. While GTM exclusively classified images into these three categories, both YOLOv8n and RF3 were able to detect and specify the location of normal colonic tissue, polyps, and resected polyps, with YOLOv8n and RF3 achieving overall accuracies of 0.84 and 0.87, respectively. (4) Conclusions: Machine learning, particularly models like GTM, shows promising results in ensuring comprehensive detection of polyps during colonoscopies.

Estimating pile group efficiency for open-ended steel piles in small group arrangements is a challenging task for designers. This paper reports on the large-scale experimental campaign performed for the BorWin gamma offshore converter platform, which involved single piles and two-pile group systems on a scale of 1:10. The experimental works included installation, dynamic end-of-driving tests, dynamic restrike tests, and static load tests of a single pile and a pair of two-pile groups in densely compacted, artificially prepared homogeneous sand. The cone penetration test (CPT) profiles and the blow counts confirmed that the foundation systems are comparable to each other. The experimental results of the single pile system were compared with conventional design methods. Such comparison indicated that CPT-based methods and load-transfer methods are applicable at the considered model scale. The bearing capacity prediction obtained via the Case Pile Wave Analysis Program (CAPWAP) method is conservative with respect to the static capacity. A consistent setup effect can be detected by analyzing the complete dynamic loading session. The pile group efficiency for the given foundation system was found to be less than 1.0 at both very small and very large soil strains, while it equaled 1.0 at failure. Key words: large-scale model tests, offshore platform, pile group. L'estimation de l'efficacite des groupes de pieux pour les pieux d'acier ouverts en petits groupes est une tache difficile pour les concepteurs. Cet article rend compte de la campagne experimentale a grande echelle realisee pour la plateforme de conversion offshore BorWin gamma, qui a implique des pieux simples et des systemes de groupes de deux pieux a l'echelle 1:10. Les travaux experimentaux comprenaient l'installation, des essais dynamiques de fin de battage, des essais dynamiques de reprise et des essais de charge statique d'un seul pieu et d'une paire de groupes de deux pieux dans un sable homogene densement compacte et artificiellement prepare. Les profils de test de penetration au cone (CPT) et les comptes de soufflage ont confirme que les systemes de fondation sont comparables les uns aux autres. Les resultats experimentaux du systeme a pieu unique ont ete compares aux methodes de conception conventionnelles. Cette comparaison indique que les methodes basees sur le CPT et les methodes de transfert de charge sont applicables a l'echelle du modele considere. La prevision de la capacite portante obtenue par la methode CAPWAP (<< Case Pile Wave Analysis Program >>) est conservatrice par rapport a la capacite statique. Un effet de reglage coherent peut etre detecte en analysant la session complete de chargement dynamique. L'efficacite du groupe de pieux pour le systeme de fondation donne s'est averee etre inferieure a 1,0 a la fois pour les tres petites et les tres grandes deformations du sol, tandis qu'elle etait egale a 1,0 a la rupture. [Traduit par la Redaction] Mots-cles : essais sur modele a grande echelle, plate-forme offshore, groupe de pieux., Introduction Pile groups are geotechnical systems typically used to support massive structures such as tall buildings, silos, power plants, and bridge piers. In the offshore sector, pile groups with a [...]

Context: The context of this study was acute coronary syndrome. Aims: The purpose of the study was to evaluate left ventricular ejection fraction (LVEF) recovery in postprimary percutaneous coronary intervention (PPCI) patients under the age of 40 years. Settings and Design: Observational study, Hyderabad Satellite Center of National Institute of Cardiovascular Disease (NICVD), Pakistan. Subjects and Methods: This study was conducted on 104 patients at “NICVD, Hyderabad Satellite Center.” ST segment elevation myocardial infarction (STEMI) patients of both genders, between 18 and 40 years of age, and those who underwent coronary angiography were included in this study. LVEF of post-PPCI patients was assessed at admission, 40 and 90 days post-PPCI. Statistical Analysis Used: The McNemar–Bowker test was conducted to assess the variations in the distribution of LVEF at 40 and 90 days as compared to the baseline. Results: A total of 104 patients were included in this study. The mean age of the patients was 34.84 ± 4.82 years. The most common risk factors were hypertension 38.5% (40) and smoking 18.3% (19). At 6 weeks, 18.3% of patient's EF was 40%–50%. At 90 days, 23.1% EF was at 40%–50%. Maximum improvement in EF was seen in patients who timely underwent PPCI. Conclusion: A significant improvement in LVEF was observed in young STEMI patients after 40 and 90 days of PPCI. Timely intervention by PPCI not only preserves LV function at baseline but is also associated with better improvement in the short term in premature STEMI patients.

Objective: The need for telemedicine was felt more than ever during the COVID-19 pandemic, which impacted health care worldwide. Therefore, this study aimed to determine the difficulties faced by patients in visiting the cardiac outpatient department during COVID-19, along with assessing the awareness and acceptability of telemedicine. Methods: In this cross-sectional study, selected patients presenting to outpatient department of a tertiary care cardiac hospital were interviewed regarding the difficulties faced by patients in visiting the outpatient department during COVID-19 and their awareness and acceptability of telemedicine using a self-designed structured questionnaire. Results: Of the 403 patients, 58.3% were male, the mean age was 53.04 ± 11.73 years, and most (77.7%) were urban residents. Ischemic heart disease was present in 69.5%, followed by hypertension (38.7%) and heart failure (29.3%). A total of 26.6% required emergency room visits. Limited appointments (55.6%) was the most common problem faced by patients during COVID-19, followed by financial issues (17.1%), fear of acquiring infection (13.4%), and limited mobility due to lockdown (22.6%). Only 12.2% were aware of telemedicine, 4.5% had previously used it, and 41.2% were willing to opt for telemedicine in the future. No internet access (39.2%) was the key barrier to the usage of telemedicine, followed by a lack of free medicine (39%) and a lack of a smart device (31.5%). Conclusion: Limited appointments due to COVID-19 restrictions has made it difficult for patients to visit the clinics, which has led to increased emergency room visits. Telemedicine awareness was found to be limited; however, many patients were willing to adopt it provided their limitations could be overcome.

Background: This study compared the open reduction and internal fixation of acetabular fractures by the ilioinguinal and modified Stoppa approaches among patients presented to Zagazig University Hospitals from December 2019 to December 2021. Methods: All patients were operated upon from the second day to the thirteen-day after trauma. Spinal anesthesia was used for 4 patients, the rest by general anesthesia. Plain x- rays, Judet views, and CT scans were obtained for all patients. The reduction was graded on all 3 radiographic views using the scoring system published by Matta. Displacement greater than 3 mm on plain radiographic view indicated poor reduction. Displacement of 1-3mm or less was defined as a satisfactory reduction, and an anatomical reduction had 1mm or less displacement. Functional outcome was performed using the Modified Merle D’Aubigné score. Results: The study included 40 patients with a mean age of 36.4 years (±10.9), divided into two groups. There was no statistically significant difference in the preoperative time delay between the two groups (p= 0.772). The mean operation time and intraoperative blood loss were significantly higher among the ilioinguinal group than in the modified Stoppa group (all p<0 .001). The needed units were significantly higher in the Ilioinguinal group than in the modified Stoppa group (p= 0.005). The mean Merle d’aubigné score was 16.4 (±1.67) among the Ilioinguinal group and 16.6 (±1.53) among the modified Stoppa group, with no statistically significant difference between both groups. Conclusions: The modified Stoppa approach may be an excellent alternative to the classic ilioinguinal approach in treating anterior acetabular fractures. [ABSTRACT FROM AUTHOR]