7 research outputs found

    Evidence of apoptosis in some cell types due to pentachlorophenol (PCP) in Heteropneustes fossilis

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    AbstractThe study aimed to clarify the role of apoptosis in pentachlorophenol (PCP) induced testicular, ovarian and renal cell genotoxicity of Heteropneustes fossilis. It was further intended to find the target germ cell type and assess the cellular and nuclear damage. Treatment of PCP was used for multiduration on the germinal tissues and they were processed to detect structural changes by light and electron microscopic evaluation and kidney cells for subsequent detection of DNA fragmentation by agarose gel electrophoresis. Findings suggest functional and morphological changes in the tissues are due to apoptosis, as evidenced by some biochemical and cytological signs. Histological observation on germinal epithelium reveals cell suicidal symptoms such as vacuolization, liquefied regions in the cytoplasm of oocytes, margination of nuclei, clumping of chromatin, and compaction of cytoplasmic organelle. Biochemical manifestation concurrent to this, is; cleavage of kidney cell DNA into low molecular weight fragments confirming apoptosis. Subsequently, it is further cleaved into nucleosome size fragments or its multiples. Ultra-structural histopathology and DNA studies conclusively lead to the PCP induced apoptosis in the exposed cell types. Results further support the usefulness of this assay in the related studies and its feasibility in generating a base line data

    Electronically reconfigurable and conformal triband antenna for wireless communications systems and portable devices

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    This paper presents the design of a triband antenna that can be electronically configured to operate at different frequencies. The proposed antenna is design to operate at sub-6GHz bands at 2.45 GHz (ISM, Wi-Fi, and WLAN), 3.3, 3.5 - 3.9 GHz (WiMAX), and 4.1 - 4.9 GHz (4G - 5G). This is achieved by connecting two open-ended stubs to a modified triangular patch radiator using PIN diodes. The antenna's performance was optimized using a 3D electromagnetic solver and its performance was verified through measurements. Moreover, the conformal analysis done on the antenna shows that the proposed technique can be used in moderately flexible wireless devices without compromising the antenna's gain, radiation efficiency and radiation patterns. These characteristics makes the proposed antenna applicable for various wireless communication systems and devices.Funding: Funder1: Universidad Carlos III de Madrid Award Number: 801538 Grant Recipient: Mohammad Alibakhshikenari Grant Recipient: Mohammad Alibakhshikenari Funder 2: HORIZON EUROPE Marie Sklodowska-Curie Actions Award Number: 801538 Grant Recipient: Mohammad Alibakhshikenari Funder 3: Ministerio de Ciencia e Innovación Award Number: MCIU/AEI/FEDER, UE Grant Recipient: Francisco Falcone The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Recent studies on Indian primates show declining population trends, even in protected areas

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    Population size and geographical range are the key quantitative criteria used by the IUCN to assess the conservation status of a species. However, such information is often incomplete and inconsistent, even for seemingly abundant species. To assess the population and conservation status of Indian primates, we conducted a systematic review of recent research using the searching, appraisal, synthesis and analysis (SALSA) approach. We reviewed a total of 41 studies on Indian primates conducted during the last 2 decades (2000–2021) for information on various parameters that influence their conservation. We found that 20 out of a total of 26 primate species were evaluated for their population status, and the majority of these studies (71%) showed an overall declining population trend. Remarkably, all but one of the studies conducted exclusively within protected areas revealed declining population trends, whereas trends were more variable for primate populations in non-protected areas. Our data indicate that only 27% (n = 7) of Indian primate species have been surveyed or re-surveyed to assess their population status within the last 5 years. Although threats vary in time and space from species to species, 78% of the studies recorded natural system modifications including habitat loss and fragmentation among the main threats to the survival of Indian primates. Most studies on the population status of Indian primates have either been spatially limited or used outdated methods. We recommend that future studies adopt robust techniques to estimate populations and work across larger geographical scales to develop effective management strategies for the conservation of primates in India

    Design of an integrated sub-6 GHz and mmWave MIMO antenna for 5G handheld devices

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    The authors appreciate financial support from Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant Agreement No 801538. As well as, this work was partially supported by the Antenna and Wireless Propagation Group (https://sites.google.com/view/awpgrp/home accessed on 16 June 2021) and from the Researchers Supporting Project number (RSP-2021/58), King Saud University, Riyadh, Saudi Arabia

    Electronically reconfigurable and conformal triband antenna for wireless communications systems and portable devices

    Get PDF
    This paper presents the design of a triband antenna that can be electronically configured to operate at different frequencies. The proposed antenna is design to operate at sub-6GHz bands at 2.45 GHz (ISM, Wi-Fi, and WLAN), 3.3, 3.5 & 3.9 GHz (WiMAX), and 4.1 & 4.9 GHz (4G & 5G). This is achieved by connecting two open-ended stubs to a modified triangular patch radiator using PIN diodes. The antenna’s performance was optimized using a 3D electromagnetic solver and its performance was verified through measurements. Moreover, the conformal analysis done on the antenna shows that the proposed technique can be used in moderately flexible wireless devices without compromising the antenna’s gain, radiation efficiency and radiation patterns. These characteristics makes the proposed antenna applicable for various wireless communication systems and devices

    Design and realization of a frequency reconfigurable antenna with wide, dual, and single-band operations for compact sized wireless applications

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    This article belongs to the Special Issue Ultra-Wideband Microwave/MM-Wave Components and Packaging.This paper presents a compact and simple reconfigurable antenna with wide-band, dual-band, and single-band operating modes. Initially, a co-planar waveguide-fed triangular monopole antenna is obtained with a wide operational frequency band ranging from 4.0 GHz to 7.8 GHz. Then, two additional stubs are connected to the triangular monopole through two p-i-n diodes. By electrically switching these p-i-n diodes ON and OFF, different operating frequency bands can be attained. When turning ON only one diode, the antenna offers dual-band operations of 3.3–4.2 GHz and 5.8–7.2 GHz. Meanwhile, the antenna with single-band operation from 3.3 GHz to 4.2 GHz can be realized when both of the p-i-n diodes are switched to ON states. The proposed compact size antenna with dimensions of 0.27λ0 × 0.16λ0 × 0.017λ0 at the lower operating frequency (3.3 GHz) can be used for several wireless applications such as worldwide interoperability for microwave access (WiMAX), wireless access in the vehicular environment (WAVE), and wireless local area network (WLAN). A comparative analysis with state-of-the-art works exhibits that the presented design possesses advantages of compact size and multiple operating modes.This work is partially supported by Antenna and Wireless Propagation Group (AWPG); https://sites.google.com/view/awpgrp

    Design and Realization of a Frequency Reconfigurable Antenna with Wide, Dual, and Single-Band Operations for Compact Sized Wireless Applications

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    This paper presents a compact and simple reconfigurable antenna with wide-band, dual-band, and single-band operating modes. Initially, a co-planar waveguide-fed triangular monopole antenna is obtained with a wide operational frequency band ranging from 4.0 GHz to 7.8 GHz. Then, two additional stubs are connected to the triangular monopole through two p-i-n diodes. By electrically switching these p-i-n diodes ON and OFF, different operating frequency bands can be attained. When turning ON only one diode, the antenna offers dual-band operations of 3.3–4.2 GHz and 5.8–7.2 GHz. Meanwhile, the antenna with single-band operation from 3.3 GHz to 4.2 GHz can be realized when both of the p-i-n diodes are switched to ON states. The proposed compact size antenna with dimensions of 0.27λ0 × 0.16λ0 × 0.017λ0 at the lower operating frequency (3.3 GHz) can be used for several wireless applications such as worldwide interoperability for microwave access (WiMAX), wireless access in the vehicular environment (WAVE), and wireless local area network (WLAN). A comparative analysis with state-of-the-art works exhibits that the presented design possesses advantages of compact size and multiple operating modes
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