MyMedR

Displaying all 11 publications

Abstract:

Sort:

Vaginal Brenner tumor with literature review: does this tumour originate from Walthard nests?

Park S, Cho MS

Malays J Pathol, 2017 Apr;39(1):89-93.
PMID: 28413211

Vaginal Brenner tumor is extremely rare. Only five cases have been reported in the English literature to date. Here we report a vaginal Brenner tumor in a 76-year old postmenopausal woman, who presented with a 2.5cm-sized sessile vaginal polyp. Microscopically, it showed characteristic features of Brenner tumor consisting of three components; transitional islands, glands, and dense fibrous stroma. The epithelial tumor cells were positive for GATA-3, p63 and ER, but negative for PAX8. The origin of Brenner tumors in the vagina is unclear, but previous reports suggested of Müllerian origin. However, our case revealed that vaginal Walthard nests could be possible precursor lesions based on their immunohistochemical staining results.
Fulltext Near-zero metamaterial inspired UHF antenna for nanosatellite communication system

Alam T, Islam MT, Cho M

Sci Rep, 2019 Mar 05;9(1):3441.
PMID: 30837629 DOI: 10.1038/s41598-019-40207-3

Epsilon-and-mu-near-zero (EMNZ) metamaterial structure inspired UHF antenna for nanosatellite has been proposed in this paper. The antenna consists of 3 × 2-unit cell array on the ground plane and a meander line radiating patch. Coaxial probe feeding technique has been obtained to excite the antenna. The meander line enables the antenna to resonate at lower UHF band and the metamaterial array is used to make the resonant frequency stable by reducing the coupling effect with metallic nanosatellite structure. The metamaterial structure exhibits EMNZ characteristics from 385 MHz to 488.5 MHz, which facilitates stable resonant frequency and higher antenna efficiency when embedded with nanosatellite structure. The proposed EMNZ inspired antenna has achieved measured impedance bandwidth (S11
Fulltext Metamaterial array based meander line planar antenna for cube satellite communication

Alam T, Almutairi AF, Samsuzzaman M, Cho M, Islam MT

Sci Rep, 2021 Jul 08;11(1):14087.
PMID: 34238984 DOI: 10.1038/s41598-021-93537-6

This research article presents a design and performance analysis of a metamaterial inspired ultra-high frequency (UHF) compact planar patch antenna for the CubeSat communication system that could be smoothly integrated with commercially available 2U Cube Satellite structure and onboard subsystem. The proposed antenna consists of two layers, one is two different width meander line antenna patch with partial ground plane and another layer is 3 × 2 near-zero-indexed metamaterial (NZIM) metamaterial array structure with ground plane. The NZIM array layer has been utilized to minimize the coupling effect with Cube Satellite structure and improve the frequency stability with enhanced antenna gain and efficiency. The fabricated antenna can operate within the lower UHF frequency band of 443.5-455 MHz. with an average peak gain of 2.5 dB. The designed antenna impedance stability characteristic has been explored after integration with the 2U Cube Satellite body layout. Besides, the antenna communication performance has been verified using 2U Cube Satellite free space path loss investigation. Small antenna volume with trade-off between the antenna size and performance are the key advantages of the proposed design, as the antenna occupies only 80 × 40 × 3.35 mm3 space of the 2U Cube Satellite body structure and the geometrical parameters can be designed to provide the best performance between 449 and 468.5 MHz.
Fulltext A Solar Panel-Integrated Modified Planner Inverted F Antenna for Low Earth Orbit Remote Sensing Nanosatellite Communication System

Alam T, Islam MT, Ullah MA, Cho M

Sensors (Basel), 2018 Jul 31;18(8).
PMID: 30065233 DOI: 10.3390/s18082480

One of the most efficient methods to observe the impact of geographical, environmental, and geological changes is remote sensing. Nowadays, nanosatellites are being used to observe climate change using remote sensing technology. Communication between a remote sensing nanosatellite and Earth significantly depends upon antenna systems. Body-mounted solar panels are the main source of satellite operating power unless deployable solar panels are used. Lower ultra-high frequency (UHF) nanosatellite antenna design is a crucial challenge due to the physical size constraint and the need for solar panel integration. Moreover, nanosatellite space missions are vulnerable because of antenna and solar panel deployment complexity. This paper proposes a solar panel-integrated modified planner inverted F antenna (PIFA) to mitigate these crucial limitations. The antenna consists of a slotted rectangular radiating patch with coaxial probe feeding and a rectangular ground plane. The proposed antenna has achieved a -10 dB impedance bandwidth of 6.0 MHz (447.5 MHz⁻453.5 MHz) with a small-sized (80 mm× 90 mm× 0.5 mm) radiating element. In addition, the antenna achieved a maximum realized gain of 0.6 dB and a total efficiency of 67.45% with the nanosatellite structure and a solar panel. The challenges addressed by the proposed antenna are to ensure solar panel placement between the radiating element and the ground plane, and provide approximately 55% open space to allow solar irradiance into the solar panel.
Fulltext Flexible Radio-Frequency Identification (RFID) Tag Antenna for Sensor Applications

Islam MT, Alam T, Yahya I, Cho M

Sensors (Basel), 2018 Nov 30;18(12).
PMID: 30513701 DOI: 10.3390/s18124212

In this paper, an inkjet-printed flexible Radio-Frequency Identification (RFID) tag antenna is proposed for an ultra-high frequency (UHF) sensor application. The proposed tag antenna facilitates a system-level solution for low-cost and faster mass production of RFID passive tag antenna. The tag antenna consists of a modified meander line radiator with a semi-circular shaped feed network. The structure is printed on photo paper using silver nanoparticle conductive ink. The generic design outline, as well as tag antenna performances for several practical application aspects are investigated. The simulated and measured results verify the coverage of universal UHF RFID band with an omnidirectional radiation pattern and a long-read range of 15 ft. In addition, the read range for different bending angles and lifetimes of the tag antenna are also demonstrated.
Fulltext HIV/AIDS-related knowledge, attitudes and perceptions: a cross-sectional household survey

Naing CM, Hakim M, Yee DA, Mun KR, Yung TC, Jian KK, et al.

Southeast Asian J. Trop. Med. Public Health, 2010 Jul;41(4):952-60.
PMID: 21073071

This study aimed to assess knowledge of and attitudes toward HIV/AIDS among a community in a semi-urban setting in Malaysia, to determine factors affecting perceptions toward people living with HIV in the community, and to provide baseline information for planning preventive measures against HIV/AIDS. This cross-sectional study was conducted in August 2009. Two hundred sixty-two household members were interviewed with a semi-structured questionnaire. Most respondents (232; 88.5%) had heard of HIV/AIDS. Only a few respondents (6; 2.6%) could correctly answer all the questionnaire items. Misconceptions about disease transmission were seen among surveyed participants, such as the belief HIV/AIDS can be contracted from saliva (104; 44.8%), mosquito bites (95; 40.9%) or casual touch (86; 37.1%). A multivariate linear regression model showed better perceptions towards people living with HIV depend on an improved knowledge of HIV/AIDS transmission. Current data emphasize the need to scale up HIV/AIDS education incorporating the mode of disease transmission.
Fulltext Understanding, perceptions and self-use of complementary and alternative medicine (CAM) among Malaysian pharmacy students

Hasan SS, Yong CS, Babar MG, Naing CM, Hameed A, Baig MR, et al.

BMC Complement Altern Med, 2011 Oct 13;11:95.
PMID: 21992582 DOI: 10.1186/1472-6882-11-95

BACKGROUND: In recent times the basic understanding, perceptions and CAM use among undergraduate health sciences students have become a topic of interest. This study was aimed to investigate the understanding, perceptions and self-use of CAM among pharmacy students in Malaysia.
METHODS: This cross-sectional study was conducted on 500 systematically sampled pharmacy students from two private and one public university. A validated, self-administered questionnaire comprised of seven sections was used to gather the data. A systematic sampling was applied to recruit the students. Both descriptive and inferential statistics were applied using SPSS® version 18.
RESULTS: Overall, the students tend to disagree that complementary therapies (CM) are a threat to public health (mean score = 3.6) and agreed that CMs include ideas and methods from which conventional medicine could benefit (mean score = 4.7). More than half (57.8%) of the participants were currently using CAM while 77.6% had used it previously. Among the current CAM modalities used by the students, CM (21.9%) was found to be the most frequently used CAM followed by Traditional Chinese Medicine (TCM) (21%). Most of the students (74.8%) believed that lack of scientific evidence is one of the most important barriers obstructing them to use CAM. More than half of the students perceived TCM (62.8%) and music therapy (53.8%) to be effective. Majority of them (69.3%) asserted that CAM knowledge is necessary to be a well-rounded professional.
CONCLUSIONS: This study reveals a high-percentage of pharmacy students who were using or had previously used at least one type of CAM. Students of higher professional years tend to agree that CMs include ideas and methods from which conventional medicine could benefit.
Fabrication of biodegradable Zn-Al-Mg alloy: Mechanical properties, corrosion behavior, cytotoxicity and antibacterial activities

Bakhsheshi-Rad HR, Hamzah E, Low HT, Kasiri-Asgarani M, Farahany S, Akbari E, et al.

Mater Sci Eng C Mater Biol Appl, 2017 Apr 01;73:215-219.
PMID: 28183601 DOI: 10.1016/j.msec.2016.11.138

In this work, binary Zn-0.5Al and ternary Zn-0.5Al-xMg alloys with various Mg contents were investigated as biodegradable materials for implant applications. Compared with Zn-0.5Al (single phase), Zn-0.5Al-xMg alloys consisted of the α-Zn and Mg2(Zn, Al)11 with a fine lamellar structure. The results also revealed that ternary Zn-Al-Mg alloys presented higher micro-hardness value, tensile strength and corrosion resistance compared to the binary Zn-Al alloy. In addition, the tensile strength and corrosion resistance increased with increasing the Mg content in ternary alloys. The immersion tests also indicated that the corrosion rates in the following order Zn-0.5Al-0.5Mg
Fulltext Microwave Imaging Sensor Using Low Profile Modified Stacked Type Planar Inverted F Antenna

Islam MT, Ullah MA, Alam T, Singh MJ, Cho M

Sensors (Basel), 2018 Sep 05;18(9).
PMID: 30189632 DOI: 10.3390/s18092949

Microwave imaging is the technique to identify hidden objects from structures using electromagnetic waves that can be applied in medical diagnosis. The change of dielectric property can be detected using microwave antenna sensor, which can lead to localization of abnormality in the human body. This paper presents a stacked type modified Planar Inverted F Antenna (PIFA) as microwave imaging sensor. Design and performance analysis of the sensor antenna along with computational and experimental analysis to identify concealed object has been investigated in this study. The dimension of the modified PIFA radiating patch is 40 × 20 × 10 mm³. The reflector walls used, are 45 mm in length and 0.2-mm-thick inexpensive copper sheet is considered for the simulation and fabrication which addresses the problems of high expenses in conventional patch antenna. The proposed antenna sensor operates at 1.55⁻1.68 GHz where the maximum realized gain is 4.5 dB with consistent unidirectional radiation characteristics. The proposed sensor antenna is used to identify tumor in a computational human tissue phantom based on reflection and transmission coefficient. Finally, an experiment has been performed to verify the antenna's potentiality of detecting abnormality in realistic breast phantom.
Fulltext Ultra-Wideband (UWB) Antenna Sensor Based Microwave Breast Imaging: A Review

Mahmud MZ, Islam MT, Misran N, Almutairi AF, Cho M

Sensors (Basel), 2018 Sep 05;18(9).
PMID: 30189633 DOI: 10.3390/s18092951

Globally, breast cancer is reported as a primary cause of death in women. More than 1.8 million new breast cancer cases are diagnosed every year. Because of the current limitations on clinical imaging, researchers are motivated to investigate complementary tools and alternatives to available techniques for detecting breast cancer in earlier stages. This article presents a review of concepts and electromagnetic techniques for microwave breast imaging. More specifically, this work reviews ultra-wideband (UWB) antenna sensors and their current applications in medical imaging, leading to breast imaging. We review the use of UWB sensor based microwave energy in various imaging applications for breast tumor related diseases, tumor detection, and breast tumor detection. In microwave imaging, the back-scattered signals radiating by sensors from a human body are analyzed for changes in the electrical properties of tissues. Tumorous cells exhibit higher dielectric constants because of their high water content. The goal of this article is to provide microwave researchers with in-depth information on electromagnetic techniques for microwave imaging sensors and describe recent developments in these techniques.
Fulltext Design and compatibility analysis of a solar panel integrated UHF antenna for nanosatellite space mission

Alam T, Islam MT, Ullah MA, Rahmatillah R, Aheieva K, Lap CC, et al.

PLoS One, 2018;13(11):e0205587.
PMID: 30427842 DOI: 10.1371/journal.pone.0205587

A compact UHF antenna has been presented in this paper for nanosatellite space mission. A square ground plane with slotted rectangular radiating element have been used. Coaxial probe feeding is used to excite. The rectangular slot of the radiating patch is responsible for resonating at lower UHF bands. One of the square faces of the nanosatellite structure works as the ground plane for the slotted radiating element. The fabricated prototype of the proposed antenna has achieved an impedance bandwidth (S11< -10dB) of 7.0 MHz (398 MHz- 405 MHz) with small size of 97 mm× 90 mm radiating element. The overall ground plane size is 100 mm × 100 mm × 0.5 mm. The proposed antenna has achieved a gain of 1.18 dB with total efficiency of 62.5%. The proposed antenna addresses two design challenges of nanosatellite antenna, (a) assurance of the placement of solar panel beneath the radiating element; (b) providing about 50% open space for solar irradiance to pass onto the solar panel, enabling the solar panel to achieve up to 93.95% of power under of normal conditions.