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  1. Article ; Online: Polarization and incident angle independent multifunctional tunable terahertz metasurface based on graphene.

    Qureshi, Ubaid Ur Rahman / Basir, Shahid / Mallek, Fatma / Hamam, Habib

    Scientific reports

    2024  Volume 14, Issue 1, Page(s) 5118

    Abstract: Motivated by the imperative demand for design integration and miniaturization within the terahertz (THz) spectrum, this study presents an innovative solution to the challenges associated with singular functionality, limited application scope, and ... ...

    Abstract Motivated by the imperative demand for design integration and miniaturization within the terahertz (THz) spectrum, this study presents an innovative solution to the challenges associated with singular functionality, limited application scope, and intricate structures prevalent in conventional metasurfaces. The proposed multifunctional tunable metasurface leverages a hybridized grapheme-metal structure, addressing critical limitations in existing designs. Comprising three distinct layers, namely a graphene-gold resonance layer, a Topas dielectric layer, and a bottom gold film reflective layer, this terahertz metasurface exhibits multifunctionality that is both polarization and incident-angle independent. The metasurface demonstrates a broadband circular dichroism (CD) function when subjected to incident circularly polarized waves. In contrast, under linear incidence, the proposed design achieves functionalities encompassing linear dichroism (LD) and polarization conversion. Remarkably, graphene's chemical potential and the incident light's state can be manipulated to tune each functional aspect's intensity finely. The proposed tunable multifaceted metasurface showcases significant referential importance within the terahertz spectrum, mainly contributing to advancing CD metamirrors, chiral photodetectors, polarization digital imaging systems, and intelligent switches.
    Language English
    Publishing date 2024-03-01
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-024-55676-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: A Miniaturized Arc Shaped Near Isotropic Self-Complementary Antenna for Spectrum Sensing Applications.

    Qureshi, Ubaid Ur Rahman / Basir, Shahid / Subhan, Fazal / Mohsan, Syed Agha Hassnain / Khan, Muhammad Asghar / Marey, Mohamed / Mostafa, Hala

    Sensors (Basel, Switzerland)

    2023  Volume 23, Issue 2

    Abstract: This paper presents the design of an arc-shaped near-isotropic self-complementary antenna for spectrum sensing application. An arc-shaped dipole with horizontal and vertical arms is used to achieve a near isotropic radiation pattern. The radiation ... ...

    Abstract This paper presents the design of an arc-shaped near-isotropic self-complementary antenna for spectrum sensing application. An arc-shaped dipole with horizontal and vertical arms is used to achieve a near isotropic radiation pattern. The radiation pattern improved by adjusting the horizontal and vertical arm lengths. Simulated and experimental results show that the proposed antenna has an impedance bandwidth of 146% (2.4-18.4 GHz) for VSWR ≤ 2 with a good radiation pattern. In order to quantify the antenna performance, antenna gain variation, bandwidth, efficiency, and size have been compared with previously reported designs. It is shown that the proposed arc-shaped antenna can achieve nearly isotropic radiation patterns with a maximum radiation efficiency of 92%. The isotropic performance of the antenna has been characterized by observing the radiation pattern and solid angle. The FR4 substrate is used as a dielectric with relative permittivity 4.4 and loss tangent of 0.02. (εr = 4.4,
    MeSH term(s) Electric Impedance ; Records
    Language English
    Publishing date 2023-01-13
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2052857-7
    ISSN 1424-8220 ; 1424-8220
    ISSN (online) 1424-8220
    ISSN 1424-8220
    DOI 10.3390/s23020927
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: A Novel Monopole Ultra-Wide-Band Multiple-Input Multiple-Output Antenna with Triple-Notched Characteristics for Enhanced Wireless Communication and Portable Systems.

    Basir, Shahid / Qureshi, Ubaid Ur Rahman / Subhan, Fazal / Khan, Muhammad Asghar / Mohsan, Syed Agha Hassnain / Ghadi, Yazeed Yasin / Ouahada, Khmaies / Hamam, Habib / Noor, Fazal

    Sensors (Basel, Switzerland)

    2023  Volume 23, Issue 15

    Abstract: This study introduces a monopole 4 × 4 Ultra-Wide-Band (UWB) Multiple-Input Multiple-Output (MIMO) antenna system with a novel structure and outstanding performance. The proposed design has triple-notched characteristics due to CSRR etching and a C- ... ...

    Abstract This study introduces a monopole 4 × 4 Ultra-Wide-Band (UWB) Multiple-Input Multiple-Output (MIMO) antenna system with a novel structure and outstanding performance. The proposed design has triple-notched characteristics due to CSRR etching and a C-shaped curve. The notching occurs in 4.5 GHz, 5.5 GHz, and 8.8 GHz frequencies in the C-band, WLAN band, and satellite network, respectively. Complementary Split-Ring Resonators (CSRR) are etched at the feed line and ground plane, and a C-shaped curve is used to reduce interference between the ultra-wide band and narrowband. The mutual coupling of CSRR enables the MIMO architecture to achieve high isolation and polarisation diversity. With prototype dimensions of (60.4 × 60.4) mm
    Language English
    Publishing date 2023-08-06
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2052857-7
    ISSN 1424-8220 ; 1424-8220
    ISSN (online) 1424-8220
    ISSN 1424-8220
    DOI 10.3390/s23156985
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Outbreak of novel Corona virus (2019-nCoV); implications for travelers to Pakistan.

    Rahman Qureshi, Ubaid Ur / Saleem, Sadia / Khan, Aisha / Afzal, Muhammad Sohail / Ali, Muhammad Shahzad / Ahmed, Haroon

    Travel medicine and infectious disease

    2020  Volume 34, Page(s) 101571

    MeSH term(s) Airports ; Betacoronavirus ; COVID-19 ; China ; Commerce ; Coronavirus Infections/epidemiology ; Coronavirus Infections/prevention & control ; Humans ; Pakistan/epidemiology ; Pandemics/prevention & control ; Pneumonia, Viral/epidemiology ; Pneumonia, Viral/prevention & control ; Quarantine ; SARS-CoV-2 ; Travel
    Keywords covid19
    Language English
    Publishing date 2020-02-04
    Publishing country Netherlands
    Document type Letter
    ZDB-ID 2170891-5
    ISSN 1873-0442 ; 1477-8939
    ISSN (online) 1873-0442
    ISSN 1477-8939
    DOI 10.1016/j.tmaid.2020.101571
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Outbreak of novel Corona virus (2019-nCoV); implications for travelers to Pakistan

    Rahman Qureshi, Ubaid Ur / Saleem, Sadia / Khan, Aisha / Afzal, Muhammad Sohail / Ali, Muhammad Shahzad / Ahmed, Haroon

    Travel Med Infect Dis

    Keywords covid19
    Publisher WHO
    Document type Article
    Note WHO #Covidence: #218
    Database COVID19

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  6. Article ; Online: Community-Based Assessment of Knowledge, Attitude, Practices and Risk Factors Regarding COVID-19 Among Pakistanis Residents During a Recent Outbreak: A Cross-Sectional Survey.

    Afzal, Muhammad Sohail / Khan, Aisha / Qureshi, Ubaid Ur Rahman / Saleem, Sadia / Saqib, Muhammad Arif Nadeem / Shabbir, Rana Muhammad Kamran / Naveed, Muhammad / Jabbar, Muhammad / Zahoor, Sarmad / Ahmed, Haroon

    Journal of community health

    2020  Volume 46, Issue 3, Page(s) 476–486

    Abstract: Exceptional precautionary measures have been adopted to stop the transmission and control of COVID-19 through the world and Pakistan is facing lockdown in this scenario. Public loyalty to precautionary measures is affected by their knowledge, attitude, ... ...

    Abstract Exceptional precautionary measures have been adopted to stop the transmission and control of COVID-19 through the world and Pakistan is facing lockdown in this scenario. Public loyalty to precautionary measures is affected by their knowledge, attitude, risk factors and practices (KAP) towards COVID-19. The present study was conducted among the Pakistani residents to observe the knowledge, attitude, practices and risk factors towards COVID-19 outbreak in Pakistan. A questionnaire was designed, and a cross-sectional survey was conducted among participants of the study area. Participants were asked the questions regarding knowledge, attitude, practices and risk factors towards COVID-19. Data were analyzed by SPSS and t/F test and correlation was applied among the knowledge, attitude, risk factors and practices. A total of 1060 questionnaires were received. 1004 were included while 56 were excluded. The highest representation was from Punjab province (65.6%), female (63%) and age group of 21-30 years (62.1%). Most participants were single (85%), Muslim (99.4%), Urdu speaking (45.6%) and were graduates (51.5%). Most of the participants were students (52.9%) and were from economically middle-class families (40.8%). The knowledge was positively correlated with attitude and practices whereas negatively correlated with risk factors (P < 0.05). The attitude was negatively correlated with risk factor and positively correlated with practices. The risk factors and practices were positively correlated with each other. Health education program to improve the COVID-19 knowledge, attitude, practices and risk factors should be initiated to combat current health challenge.
    MeSH term(s) Adult ; COVID-19/epidemiology ; COVID-19/prevention & control ; Cross-Sectional Studies ; Disease Outbreaks ; Female ; Health Knowledge, Attitudes, Practice ; Humans ; Male ; Pakistan/epidemiology ; Risk Factors ; Surveys and Questionnaires ; Young Adult
    Keywords covid19
    Language English
    Publishing date 2020-07-13
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 426631-6
    ISSN 1573-3610 ; 0094-5145
    ISSN (online) 1573-3610
    ISSN 0094-5145
    DOI 10.1007/s10900-020-00875-z
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Community-Based Assessment of Knowledge, Attitude, Practices and Risk Factors Regarding COVID-19 Among Pakistanis Residents During a Recent Outbreak

    Afzal, Muhammad Sohail / Khan, Aisha / Qureshi, Ubaid Ur Rahman / Saleem, Sadia / Saqib, Muhammad Arif Nadeem / Shabbir, Rana Muhammad Kamran / Naveed, Muhammad / Jabbar, Muhammad / Zahoor, Sarmad / Ahmed, Haroon

    Journal of Community Health ; ISSN 0094-5145 1573-3610

    A Cross-Sectional Survey

    2020  

    Keywords Public Health, Environmental and Occupational Health ; Health(social science) ; covid19
    Language English
    Publisher Springer Science and Business Media LLC
    Publishing country us
    Document type Article ; Online
    DOI 10.1007/s10900-020-00875-z
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article: Community-Based Assessment of Knowledge, Attitude, Practices and Risk Factors Regarding COVID-19 Among Pakistanis Residents During a Recent Outbreak: A Cross-Sectional Survey

    Afzal, Muhammad Sohail / Khan, Aisha / Qureshi, Ubaid Ur Rahman / Saleem, Sadia / Saqib, Muhammad Arif Nadeem / Shabbir, Rana Muhammad Kamran / Naveed, Muhammad / Jabbar, Muhammad / Zahoor, Sarmad / Ahmed, Haroon

    J. community health

    Abstract: Exceptional precautionary measures have been adopted to stop the transmission and control of COVID-19 through the world and Pakistan is facing lockdown in this scenario. Public loyalty to precautionary measures is affected by their knowledge, attitude, ... ...

    Abstract Exceptional precautionary measures have been adopted to stop the transmission and control of COVID-19 through the world and Pakistan is facing lockdown in this scenario. Public loyalty to precautionary measures is affected by their knowledge, attitude, risk factors and practices (KAP) towards COVID-19. The present study was conducted among the Pakistani residents to observe the knowledge, attitude, practices and risk factors towards COVID-19 outbreak in Pakistan. A questionnaire was designed, and a cross-sectional survey was conducted among participants of the study area. Participants were asked the questions regarding knowledge, attitude, practices and risk factors towards COVID-19. Data were analyzed by SPSS and t/F test and correlation was applied among the knowledge, attitude, risk factors and practices. A total of 1060 questionnaires were received. 1004 were included while 56 were excluded. The highest representation was from Punjab province (65.6%), female (63%) and age group of 21-30 years (62.1%). Most participants were single (85%), Muslim (99.4%), Urdu speaking (45.6%) and were graduates (51.5%). Most of the participants were students (52.9%) and were from economically middle-class families (40.8%). The knowledge was positively correlated with attitude and practices whereas negatively correlated with risk factors (P < 0.05). The attitude was negatively correlated with risk factor and positively correlated with practices. The risk factors and practices were positively correlated with each other. Health education program to improve the COVID-19 knowledge, attitude, practices and risk factors should be initiated to combat current health challenge.
    Keywords covid19
    Publisher WHO
    Document type Article
    Note WHO #Covidence: #640798
    Database COVID19

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