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International audience; Unlabelled - The study was aimed at the identification of a potential anti-cancer compound from the leaf extract of , against pancreatic cancer cells (PANC-1). Out of different extracts tested, methanolic extract showed significant cytotoxicity at an IC of 289.5 ± 0.03 µg/mL after 24 h (MTT assay). The safety of the extract was ascertained using normal pancreatic cells (hTERT-HPNE). Methanolic extract was able to induce apoptosis in 28.9 ± 0.01% of PANC-1 cells as determined by flow cytometry. RT-PCR analysis of PANC-1 cells also recorded an increase in the mRNA expression of pro-apoptotic genes i.e., (12.82 folds), (10 folds) and (8.74 folds) after treatment. Expression of other pro-apoptotic genes such as and was also upregulated by 4.04 and 4.01 folds, respectively. However, the mRNA expression of anti-apoptotic genes, , and was found to be downregulated. The bioactive extract was then fractionated on preparative silica gel plates into 24 bands. Out of these, band fraction 9 exhibited significant cytotoxicity (IC 219 ± 0.04 µg/mL) on the PANC-1 cells. The mass spectral (HPLC-MS) and FTIR analysis of the fraction indicated the bioactive compound to be a derivative of Diosgenin, which can be a possible candidate for cancer therapeutics in future. Supplementary information - The online version contains supplementary material available at 10.1007/s13205-022-03155-w.

A new small high-gain wideband rectangular patch antenna is proposed in this paper. The antenna has a simple structure where the dimensions are about 11 mm by 7 mm by 1.58 mm leading to a good bandwidth. The antenna structure is optimized and simulated using electromagnetic commercial software, and the measured bandwidth defined by return loss

Artificial intelligence has had an impact on a variety of fields, including medicine and, most importantly, cardiovascular diseases. Indeed, early diagnosis of many disorders is a serious medical issue. In this article, we will compare various machine learning algorithms in order to select the optimal one for diagnosing people who might suffer from heart disease based on a variety of clinical data from patients. The effort in this article is focused on studying the dataset using data mining algorithms, and also explaining the used machine learning algorithms in predicting heart disease, in order to assist future researchers in getting the most out of these skills.

International audience; In this work, a new patch antenna array containing 16-elements, Parallel-series Feed operated at millimeter waves, for 5G mobile wireless applications have been designed and realized. The proposed antenna contains 16-elements excited by one port, through a Y-Junction power divider. The array has a bandwidth of 27.5 to 28. 35GHz and a high gain of 17.5dBi. © 2019 IEEE.

In this work, we study the performance of an antenna in microstrip technology designed especially for micro-cellular applications in a real context of mobile radio-telephony. To accomplish this, we designed an indoor cellular test network and implemented basic functions of the GSM protocol, by using Open Base Transceiver Station (OpenBTS): an open-source cellular infrastructure that uses Software Defined Radio (SDR) as a platform. Our proposed prototype is based on the Universal Software Radio Peripheral (USRP) device from National Instrument that is designed to operate in the sub-6 GHz band. Finally, a preliminary test of the Quality of Service (QoS) has been quarried-out by measuring the Receive Signal Strength Indicator (RSSI) between the deployed Base Station and the connected mobile stations (MS), and that for different scenarios and distances.

Microwave imaging is the most attractive diagnostic technique for medical imaging interested by different scientific research teams. This paper proposes an algorithm namely Confocal Microwave Imaging (CMI) for detecting and locating a tumor by analyzing different electromagnetic signals. Firstly, an UWB antenna is designed and optimized to obtain a good impedance match over the required frequency range (3.1 GHz to 14 GHz) according to the FCC. Finally, the confocal microwave imaging (CMI) algorithm has been implemented and applied to create an image of tumor. The results obtained proved the feasibility of detecting breast tumors using CMI method.

In this paper a new design of a dual small band small elliptical microstrip antenna is proposed for Ku and K band satellite applications. The basic antenna structure is an elliptical patch with inset-feed, which is modified by adding two rectangular slots in the radiation patch. The proposed antenna has been designed and fabricated on 1.58 mm thick FR4 substrate whose dielectric constant is 4.4, with dimensions of about 10×12×1.58 mm³. The antenna structure was validated using two different electromagnetic solvers and by measuring the results using a Vector Network Analyzer (VNA). The measured and simulated results show two resonant frequencies that define two bandwidths. Moreover, the proposed antenna frequency bands and the consistent and symmetrical radiation patterns make it an appropriate candidate for many applications such as the Ku/K band satellite application and wireless communications.

Breast cancer affects many women in many ways. Early diagnosis is the most important key for detecting malignant tissue. In this paper, we present the design of a microstrip patch antenna for ultra wide band (UWB) biomedical applications covering the full range of FCC frequencies (3.1 GHz to 14 GHz). We have used a single antenna with various positions to scan the whole breast phantom. A confocal microwave imaging (CMI) algorithm has been implemented and applied to create a 2D image of the tumor. The results obtained suggest the feasibility of using CMI method for detecting small breast tumors with high precision and more safety .

In this paper, a new 16-elements, Corporate-series Feed Rectangular Patch Antenna Array operated at 28GHz, for 5G mobile wireless applications have been designed and simulated. The proposed array contains 16-elements excited by one port, through a Y-Junction power divider. The array has a wide bandwidth from 26.42 to 28.94GHz and a high gain of 17.1dB with a radiation efficiency of 92%. The simulations are based using both HFSS (High-Frequency Structure Simulator) and CST Microwave Studio Software.

This paper describes the detection of tumors in human breast tissues using an UWB planar antenna operating at a frequency recommended by FCC. The antenna has a measured bandwidth from 3.92 GHz to 11.32 GHz for |S11

In this work a new design and development of a $\pmb{4\text{x}2}$ microstrip patch antenna array with circular polarized elements. The basic antenna structure is a rectangular patch antenna with truncated corners. He is designed on 1.58 mm thick FR4 substrate whose dielectric constant is 4.4, with dimensions of about $\pmb{12\times 15\times 1.58\ \text{mm}^{3}}$ . The array dimensions of about $\pmb{60\text{x}30\text{x}1.58\ \text{mm}^{3},}$ he is fed by 50 ohm line, and he consists of two symmetrical array of microstrip subarrays, each subarray is a $\pmb{2\text{x}2}$ patches element microstrip. Each array comprised 4 elements of patch.

Interference management is the key point in the deployment of ultra-dense networks. Several techniques in physical and data-link layers have been discussed and proposed to provide lower power and better network capacity, while minimizing the cost and complexity of FemtoCell deployment. The applicability of an antenna with microstrip technology that employs multiple elements is developed here for coverage enhancement of FemtoCell network. The antenna proposed in this research has a size of 35 x 35 x 1.58 mm 3 , it is printed on a commercially available FR4 dielectric substrate and designed for the frequency band from 1.9 GHz to 3.5 GHz. The different results obtained of the studied antenna in the FemtoCell scenario are discussed.

In this article, a miniaturized rectangular printed antenna that meets the ultrawideband (UWB) characteristics in terms of bandwidth and reflection coefficient is proposed. The designed antenna with dimension of 25×16 mm2 (L × W) was fabricated on FR-4 epoxy dielectric with relative permittivity of 4.4. SMA female connector is used for feeding with characteristic impedance of 50 Ω. The antenna exhibits good UWB characteristics and has the capability of operating between 3.92 to 11.32 GHz. The proposed antenna has omnidirectional radiation pattern on most of the operating band. The measured reflection coefficient of the proposed antenna is compared with the simulated one; good agreement is observed. Also, radiation pattern and gain of the antenna are presented. All simulations are carried out using the EM commercial simulators, HFSS, and CST. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:460–463, 2015

In this paper, a comparative study of dipole and patch antennas commonly used in portable telephones is investigated. The two models antennas are considered working at 900, 1800 and 2450 MHz bands. Thus, we have included different distances between the mobile phone and the human head model. This study shows the effects of electromagnetic waves on the human head model. The objective is to evaluate the SAR in simulation anatomic based model of the human head for different antenna-head distances and in many frequencies. All numerical simulations results are performed using Ansoft HFSS software.

Microwave imaging is explored as an imaging modality for early detection of breast cancer. When exposed to electromagnetic waves, the breast tumor has electrical properties that are substantially different from those of healthy breast tissue. This paper for the detection of breast cancer. We examine the ability to detect tumors by a UWB microstrip antenna operating at 6 GHz. Using a simple model in the form of a cone. This model consists of the breast skin, fat, and tumor tissues. The study is done according to several distances between the patch antenna and the model of the breast. Simulation and measured results are presented, namely, reflection coefficient, gain and radiation pattern of the antenna and the current density in the breast skin, fatty tissue and the tumor to give us a clear insight into the concept studied.

A Compact microstrip antenna with rectangular slotted radiating element has been developed. Four slots have been introduced on the radiating element with the use of a partial ground plane and a wideband response has been obtained. The bandwidth of the proposed antenna is 1.7 GHz with a percentage bandwidth of 71%. A low-cost dielectric (FR4_EPOXY) has been considered in the development of the proposed antenna. The obtained frequency band is from 1.9 GHz to 3.6 GHz. To investigate the robustness of our modelled antenna the simulation process has been carried out using two different solvers (Finite Element Method and Finite Integration Technique). In addition, the designed antenna was realized and these results were compared with those of the simulation. The proposed antenna is suitable for many LTE bands {1, 3, 7… 38, 40} broadly deployed in European, South American, Asian, and African countries, Wi-Fi (2.4 GHz), and WiMAX technology (3.5 GHz).

This paper presents an original elliptical microstrip patch antenna is proposed for Ku/K band satellite applications. The proposed antenna has a simple structure, small size with dimensions of about 10×12×1.58 mm³. The antenna has been designed and simulated on an FR4 substrate with dielectric constant 4.4 and thickness of 1.58 mm. The design is simulated by two different electromagnetic solvers. The results from the measured data show that the antenna has two resonant frequencies that define 2 bandwidths, defined by a return loss of less than -10 dB, and are: (14.44 GHz, 829 MHz) and (21.05 GHz, 5126 MHz),with the gain 5.59 dB and 5.048 dB respectively. The proposed antenna can be used in many applications such as in satellite, and wireless communications.

A new measurement technique is presented to determine the complex permittivity of a dielectric material. The dielectric sample is loaded in a short-circuited rectangular waveguide. The reflection coefficient of the waveguide is measured by Network analyzer and calculated as a function of the complex permittivity using finite difference time domain method (FDTD). The Newton–Raphson method is then used to determine complex permittivity by matching the calculated value with the measured value. A comparison of determined values of the dielectric constant obtained from the Nicholson–Ross technique and the FDTD method is presented. Numerical resultants for complex permittivity of Teflon and Plexiglass measured at the microwave frequencies are presented. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1964–1968, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22611

In this paper, a simple waveguide measurement technique is presented to determine the complex permittivity of a dielectric material. The dielectric sample is loaded in a short-circuited rectangular waveguide. The reflection coefficient of the waveguide is measured by Network analyser and calculated as a function of the complex permittivity using theory of transmissions lines. The Newton Raphson method is then used to determine de complex permittivity by matching the calculated value with the measured value. The results obtained using Newton Raphson are in good agreement with the results obtained by the Nicholson-Ross technique.

This paper presents a simple waveguide measurement technique to evaluate the complex permittivity of a homogenous dielectric material. The dielectric sample is loaded in the transmission line rectangular waveguide WR90. The S-parameters of the waveguide are measured by Network analyzer and calculated as a function of the complex permittivity using theory of transmissions lines. Using the MatLab Optimization Tools simple MatLab scripts are written to search for complex permittivity of a dielectric material so as to match the measured and calculated values of S-parameters. The complex permittivity of Teflon and Nylon at the X-band frequencies are then determined.

This paper presents a new method to analyze the discontinuity of a multilayer dielectric material. The multilayer material sample is loaded in an X-band rectangular waveguide and its two port S-parameters are simulated as a function of frequency using the software Ansoft HFSS. Also, by applying the mode matching technique, expressions for the S-parameters of the multilayer dielectric material as a function of complex permittivity of individual layers are developed. A single layer material formed by using materials such as Teflon, a number of two layer materials formed by combinations of plexiglass and Teflon and sample of three layer materials are also presented.

This article describes in the first, the design of a new microstrip patch antenna for WIFI/WLAN applications (IEEE 802.11 b/g/n). Secondly, the article presents the effect of electromagnetic waves on a model of the human head exposed to the antenna designed in the ISM2450 band. By adopting a model tissue to seven layers of an adult. The objective is to evaluate the specific absorption rate (SAR) due to the propagation of electromagnetic waves along a human head for different antenna-head distances in simulation anatomic based model of the human head at a frequency of 2450MHz. All results, reflection coefficient, VSWR, radiation pattern, SAR and field distributions are presented. The simulation analysis was performed using the HFSS software. MGI-L�z for homogeneous wireless sensor networks based upon the framework of LEACH such as the network is divided into multi groups to prevent the concentration of cluster head in a particular area of ​​the network, and the cluster head selection is based on high residual energy and a short distance from the base station (BS) in each communication round, which minimizes the communication energy of wireless sensor nodes, and hence, increases lifetime of the whole network. Simulations using MATLAB software show improved lifetime in different levels of Grouping compared to the classical algorithm LEACH.

This article presents the design of a miniaturized multilayer patch antenna for microwave medical imaging applications. We propose a miniature multilayer printed antenna that meets the UWB characteristics in terms of bandwidth and reflection coefficient. This antenna is designed for a system to detect malignant tumors by microwave imaging. The structure of the antenna is nearly the same with the traditional microstrip patch antenna except the feeding method. By using T-probe and multilayer structure. The result shows that the impedance bandwidth (VSWR ≤ 2) of the proposed antenna is 6.40GHz (5.12 GHz to 11.52 GHz), which is equivalent to 76.93%. The gain of the antenna is almost 6.5dB across the operating bandwidth.

A new technique is presented to determine the complex permittivity of each layer for a bi-layer dielectric material. The bi-layer material sample is loaded in a Ku-band rectangular waveguide and its two port S-parameters are measured as a function of frequency using the E8634A Network Analyzer. Also, by applying the mode matching technique, expressions for the S-parameters of the bi-layer dielectric material as a function of complex permittivity of each layer are developed. To estimate the complex permittivity of each layer’s dielectric material, the square sums of errors between the measured and calculated S-parameters are minimised using a nonlinear optimization algorithm. The complex permittivity of each layer for a bi-layer dielectric material such as FR4-Teflon, FR4-Delrin and Delrin-Teflon are determined at the Ku-band frequencies, and the average relative errors between the individual dielectric materials and those of each individual layer of the bi-layer dielectric materials are calculated.

Les auteurs decrivent une installation d'irradiation des catalyseurs permettant d'etudier leur comportement sous champ electromagnetique microonde intense. Ils discutent les conditions qu'ils ont imposees pour que les catalyseurs soient irradies de facon homogene, et les precautions prises pour mesurer la temperature en presence du champ electromagnetique. Ils decrivent le systeme de contre reaction qui stabilise celle-ci autour d'une valeur de consigne choisie a l'avance. L'efficacite et la precision du servo-mecanisme sont illustrees par plusieurs exemples.