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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

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 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 paper, a simple microstrip antenna for the radio frequency identification (RFID) applications and wireless local area network (WLAN) is presented. The antenna has two operating bands at 2.45 and 5.8 GHz, which are reserved for RFID applications and WLAN applications. The studied antenna design, analysis and characterization have been performed using CST electromagnetic simulation software. The antenna was analyzed with FR4 substrate. Reflection coefficient, VSWR and directivity results were simulated, presented and discussed. The designed antenna was fabricated on ArlonAD320 dielectric with relative permittivity of 3.2. SMA female connector is used for feeding with characteristic impedance of 50 Ω. The measured reflection coefficient of the proposed antenna is compared with the simulated one, good agreement is observed. The proposed antenna is simple in design and compact in size, providing broadband impedance matching, consistent omnidirectional radiation patterns and appropriate gain characteristics (>1.5 dBi) in the RFID frequencies regions.

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.

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.

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.