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This paper introduces a planar antipodal meander line antenna fabricated using RO3003 substrate. The proposed antenna is designed to radiate in the end-fire direction, achieving a maximum measured gain of 10.43 dBi within its working bandwidth, which ranges from 2.24 GHz to 2.7 GHz, covering long-range WLAN/WiMAX applications. A systematic procedure is adopted in the design process to prove its tunability to cover other application requirements in terms of gain and bandwidth. The proposed design steps show that the bandwidth and the gain can independently be controlled by adjusting specific design parameters such as the number of radiators and the scaling factor. The antenna is fine-tuned using sensitivity analysis and parametric study to guarantee optimum operation at the desired bandwidth. Experimental measurements of the fabricated design demonstrate a high degree of correlation with simulations conducted using CST and HFSS. In comparison to other end-fire antennas presented in the literature, the proposed design manifests its capability to provide high gain for WLAN/WiMAX nodes connectivity. The measurements show that the proposed traveling wave antenna exhibits a high radiation efficiency with maximum value of 99.8% at 2.35 GHz. The measured side lobe level is found to be below - 18 dB and - 20 dB at 2.45 GHz along the E - and H -planes, respectively. Apart from its excellent radiation performance, the antenna is characterized by its low profile and fabrication simplicity.

Condensation of β-Oxo anilide 1 with malononitrile afforded 1,8-naphthyridine derivative 5. The reaction οf 1 with each of cyanothioacetamide and ethyl cyanoacetate yields pyridine derivatives 7 and 10. Also, 1 reacted with each of arylidenecyanothioacetamide or a mixture of acetaledelyde/cyanothioacetamide to yield 5-acetylnicotinonitrile derivatives 15 and 17 respectively. Treatment of 15 with hydrazine hydrate afforded hydrazinonicotinonitrile derivative 18 . Furthermore, compound 15 was reacted with ethyl chloroacetate to afford thieno[2,3– b ]pyridine derivative 20. Compound 17 reacts with elementary sulfur to yield the thienopyridine derivative 21 . Compound 21 reacted with arylidinemalononitrile yielding the isoquinolines 22a , b . Quantum chemical calculation optimization of DFT and frequency of synthesized compounds using Gaussian 09 and B3LYP methods. The basis set 6-31G (d, p) from which the descriptor was obtained explains the reactivity or stability οf the synthesized compounds and their investigation as corrosion inhibitors. The results demonstrate the compound’s potential as effective inhibitors of organic corrosion of some metals.

ObjectiveCalcium metabolism has long been implicated in aortic stenosis (AS). Studies assessing the long-term safety of oral calcium and/or vitamin D in AS are scarce yet imperative given the rising use among an elderly population prone to deficiency. We sought to identify the associations between supplemental calcium and vitamin D with mortality and progression of AS.MethodsIn this retrospective longitudinal study, patients aged ≥60 years with mild-moderate native AS were selected from the Cleveland Clinic Echocardiography Database from 2008 to 2016 and followed until 2018. Groups were stratified into no supplementation, supplementation with vitamin D alone and supplementation with calcium±vitamin D. The primary outcomes were mortality (all-cause, cardiovascular (CV) and non-CV) and aortic valve replacement (AVR), and the secondary outcome was AS progression by aortic valve area and peak/mean gradients.ResultsOf 2657 patients (mean age 74 years, 42% women) followed over a median duration of 69 months, 1292 (49%) did not supplement, 332 (12%) took vitamin D alone and 1033 (39%) supplemented with calcium±vitamin D. Calcium±vitamin D supplementation was associated with a significantly higher risk of all-cause mortality (absolute rate (AR)=43.0/1000 person-years; HR=1.31, 95% CI (1.07 to 1.62); p=0.009), CV mortality (AR=13.7/1000 person-years; HR=2.0, 95% CI (1.31 to 3.07); p=0.001) and AVR (AR=88.2/1000 person-years; HR=1.48, 95% CI (1.24 to 1.78); p<0.001). Any supplementation was not associated with longitudinal change in AS parameters in a linear mixed-effects model.ConclusionsSupplemental calcium with or without vitamin D is associated with lower survival and greater AVR in elderly patients with mild-moderate AS.

A compact and low-profile S-slot antenna for millimeter-wave wireless communication applications is presented in this paper. The antenna employs an S-shaped slot etched within a ground plane and excited by a hook-shaped microstrip feeding line to radiate a linearly polarized wave with a bidirectional broadside radiation beam. The antenna geometrical parameters are optimized to cover the n257 and n261 5G bands of the 5G mobile communications. The proposed antenna is fabricated and measured. Simulated and measured results demonstrate good impedance matching, with a measured fractional bandwidth of 18.3% and a maximum realized gain of 4.8 dBi across the desired operating bandwidth for the S-slot antenna with extended ground plane necessary for the purpose of measurements. The performance remains largely unaffected when the ground plane is reduced, highlighting the antenna’s suitability for compact implementations. Consequently, the proposed antenna is well suited for indoor 5G small-cell deployments and future railway wireless communication systems. Moreover, it can serve as a unit element in MIMO arrays or larger antenna configurations. To further demonstrate scalability and system-level applicability, the antenna element is extended into a compact eight-element MIMO array providing dual linear polarization. The array exhibits low mutual coupling, an envelope correlation coefficient on the order of 10−3, and a diversity gain approaching 10 dB. These results demonstrate highly independent radiation characteristics and reliable MIMO performance in multipath environments.

Background Pneumoperitoneum poses an important diagnostic sign determining the urgency of management of patients in an emergency department. Chilaiditi sign is a rare radiologic finding of large intestines transposition between the diaphragm and the liver. If the patient becomes symptomatic, then the condition is called Chilaiditi syndrome. Case presentation We present a rare case of a 49-year-old Egyptian man who presented to our emergency department complaining of cough and vague abdominal discomfort who was found to have Chilaiditi syndrome diagnosed radiologically by computed tomography scan. He was conservatively managed rather than undergoing invasive non-warranted diagnostic and therapeutic testing that may have resulted in increased morbidity. Conclusions A review of the current literature on Chilaiditi syndrome is provided with a focus on increasing the familiarity of health care professionals with the conditions and stressing the importance of a physical examination in evaluating patients with what appears to be air under the diaphragm.

Pyrazolylphthalimide derivative 4 was synthesized and reacted with different reagents to afford the target compounds imidazopyrazoles 5-7, pyrazolopyrimidines 9, 12, 14 and pyrazolotriazines 16, 17 containing phthalimide moiety. The prepared compounds were established by different spectral data and elemental analyses. Additionally, all synthesized derivatives were screened for their antibacterial activity against four types of Gram + ve and Gram-ve strains, and for antifungal activity against two fungi micro-organisms by well diffusion method. Moreover, the antiproliferative activity was tested for all compounds against human liver (HepG-2) cell line in comparison with the reference vinblastine. Moreover, drug-likeness and toxicity risk parameters of the newly synthesized compounds were calculated using in silico studies. The data from structure-actvity relationship (SAR) analysis suggested that phthalimide derivative bearing 3-aminopyrazolone moiety, 4 illustrated the best antimicrobial and antitumor activities and might be considered as a lead for further optimization. To investigate the mechanism of the antimicrobial and anticancer activities, enzymatic assay and molecular docking studies were carried out on E. coli topoisomerase II DNA gyrase B and VEGFR-2 enzymes.

A novel series of pyrazole analogues including hydrazones, pyrazolo[4,3-c]-pyridazines, pyrazolo[3,4-e][1,2,4]triazine and pyrazolo[3,4-d][1,2,3]triazoles was designed, synthesised and screened for their in vitro antimicrobial and DHFR inhibition activity. Compounds bearing benzenesulphonamide moiety incorporated with 3-methyl-5-oxo-1H-pyrazol-4(5H)-ylidene) hydrazine 3a or 6-amino-7-cyano-3-methyl-5H-pyrazolo[4,3-c]pyridazine 6a revealed excellent and broad spectrum antimicrobial activity comparable to ciprofloxacin and amphotericin B as positive antibiotic and antifungal controls, respectively. Furthermore, these derivatives proved to be the most active DHFR inhibitors with IC 50 values 0.11 ± 1.05 and 0.09 ± 0.91 µM, in comparison with methotrexate (IC 50 = 0.14 ± 1.25 µM). The in silico studies were done to calculate the drug-likeness and toxicity risk parameters of the newly synthesised derivatives. Additionally, the high potency of the pyrazole derivatives bearing sulphonamide against DHFR was confirmed with molecular docking and might be used as an optimum lead for further modification.

BackgroundRandomised trials evaluating the efficacy and safety of fractional flow reserve (FFR)-guided versus angiography-guided revascularisation among patients with obstructive coronary artery disease (CAD) have yielded mixed results.AimsTo examine the comparative efficacy and safety of FFR-guided versus angiography-guided revascularisation among patients with obstructive CAD.MethodsAn electronic search of MEDLINE, SCOPUS and Cochrane databases without language restrictions was performed through November 2021 for randomised controlled trials that evaluated the outcomes of FFR-guided versus angiography-guided revascularisation. The primary outcome was major adverse cardiac events (MACE). Data were pooled using a random-effects model.ResultsThe final analysis included seven trials with 5094 patients. The weighted mean follow-up duration was 38 months. Compared with angiography guidance, FFR guidance was associated with fewer number of stents during revascularisation (standardised mean difference=−0.80; 95% CI −1.33 to −0.27), but no difference in total hospital cost. There was no difference between FFR-guided and angiography-guided revascularisation in long-term MACE (13.6% vs 13.9%; risk ratio (RR) 0.97, 95% CI 0.85 to 1.11). Meta-regression analyses did not reveal any evidence of effect modification for MACE with acute coronary syndrome (p=0.36), proportion of three-vessel disease (p=0.88) or left main disease (p=0.50). There were no differences between FFR-guided and angiography-guided revascularisation in the outcomes all-cause mortality (RR 1.16, 95% CI 0.80 to 1.68), cardiovascular mortality (RR 1.27, 95% CI 0.50 to 3.26), repeat revascularisation (RR 0.99, 95% CI 0.81 to 1.21), recurrent myocardial infarction (RR 0.92, 95% CI 0.74 to 1.14) or stent thrombosis (RR 0.61, 95% CI 0.31 to 1.21).ConclusionAmong patients with obstructive CAD, FFR-guided revascularisation did not reduce the risk of long-term adverse cardiac events or the individual outcomes. However, FFR-guided revascularisation was associated with fewer number of stents.PROSPERO registration numberCRD42021291596.