Displaying publications 1 - 20 of 87 in total

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  1. Islam MM, Faruque MR, Islam MT
    ScientificWorldJournal, 2014;2014:528489.
    PMID: 24971379 DOI: 10.1155/2014/528489
    A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs) is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm(2), and VSWR < 2, observing band elimination of 5.5 GHz WLAN band.
  2. Islam MM, Islam MT, Faruque MR
    ScientificWorldJournal, 2013;2013:378420.
    PMID: 24385878 DOI: 10.1155/2013/378420
    The dual-band operation of a microstrip patch antenna on a Duroid 5870 substrate for Ku- and K-bands is presented. The fabrication of the proposed antenna is performed with slots and a Duroid 5870 dielectric substrate and is excited by a 50 Ω microstrip transmission line. A high-frequency structural simulator (HFSS) is used which is based on the finite element method (FEM) in this research. The measured impedance bandwidth (2 : 1 VSWR) achieved is 1.07 GHz (15.93 GHz-14.86 GHz) on the lower band and 0.94 GHz (20.67-19.73 GHz) on the upper band. A stable omnidirectional radiation pattern is observed in the operating frequency band. The proposed prototype antenna behavior is discussed in terms of the comparisons of the measured and simulated results.
  3. Islam MT, Samsuzzaman M
    ScientificWorldJournal, 2014;2014:673846.
    PMID: 24987742 DOI: 10.1155/2014/673846
    This paper introduces a new configuration of compact, triangular- and diamond-slotted, microstrip-fed, low-profile antenna for C/X band applications on polytetrafluoroethylene glass microfiber reinforced material substrate. The antenna is composed of a rectangular-shaped patch containing eight triangles and two diamond-shaped slots and an elliptical-slotted ground plane. The rectangular-shaped patch is obtained by cutting two diamond slots in the middle of the rectangular patch, six triangular slots on the left and right side of the patch, and two triangular slots on the up and down side of the patch. The slotted radiating patch, the elliptical-slotted ground plane, and the microstrip feed enable the matching bandwidth to be widened. A prototype of the optimized antenna was fabricated on polytetrafluoroethylene glass microfiber reinforced material substrate using LPKF prototyping machine and investigated to validate the proposed design. The simulated results are compared with the measured data, and good agreement is achieved. The proposed antenna offers fractional bandwidths of 13.69% (7.78-8.91 GHz) and 10.35% (9.16-10.19 GHz) where S11 < -10 dB at center frequencies of 8.25 GHz and 9.95 GHz, respectively, and relatively stable gain, good radiation efficiency, and omnidirectional radiation patterns in the matching band.
  4. Samsuzzaman M, Islam MT
    ScientificWorldJournal, 2014;2014:604375.
    PMID: 24895656 DOI: 10.1155/2014/604375
    A novel probe-fed compact inverted S-shaped multifrequency patch antenna is designed. By employing two rectangular slots that change the conventional rectangular patch into an inverted S-shaped patch, the antenna is able to operate in triple frequency in the X-band. The performance criteria of the proposed design have been experimentally verified by fabricating a printed prototype. The measured results show that the -10 dB impedance bandwidth of the proposed antenna at lower band is 5.02% (8.69-9.14 GHz), at middle band is 9.13% (10.47-11.48 GHz), and at upper band is 3.79% (11.53-11.98 GHz). Two elliptical slots are introduced in the ground plane to increase the peak gain. The antenna is excited by a simple probe feeding mechanism. The overall antenna dimension is  0.52λ × 0.60λ × 0.046λ at a lower resonance frequency of 9.08 GHz. The antenna configuration and parametric investigation are conducted with the help of the high frequency structural simulator, and a good agreement is achieved between the simulated and measured data. The stable gain, omnidirectional radiation pattern, and consistent radiation efficiency in the achieved operating band make the proposed antenna a suitable candidate for X-band applications.
  5. Mahmud A, Islam MR
    Int J Community Wellbeing, 2021;4(3):315-321.
    PMID: 34723103 DOI: 10.1007/s42413-020-00071-w
    This commentary looks at the social stigma as a barrier to Covid-19 responses to community well-being in Bangladesh. The Covid-19 in Bangladesh particular the way the people respond this has many dimensions to view from sociological perspective. The main objective of this commentary is to analysis how this response is related to social stigma. Gathering information from the recent literature, results showed that there are number of causes around such stigma that include misinformation, feeling of insecurity, fear of responsibility, administrative malfunction, and lack of trust on treatment. These causes of stigma have number of forms such as humor-prone stigma, residential stigma, organizational stigma, community-stigma, and apathetical stigma. Results also show that there are many effects of stigma such as health-risks, harassment, discrimination, life-insecurity, psychological disorder, loss of social capital and emotional capital, shattering family bond and social solidarity that work as barrier to community well-being. This commentary recommends to overcome the barriers through strengthening and decentralization of the COVID-19 medical facilities including testing, tracing, formal quarantining, and special treatment for coronavirus in coronavirus hospitals by allocating a large figure of the state budget and also by taking initiatives of public-private partnership for health management.
  6. Islam MT, Mahmud MZ, Islam MT, Kibria S, Samsuzzaman M
    Sci Rep, 2019 10 29;9(1):15491.
    PMID: 31664056 DOI: 10.1038/s41598-019-51620-z
    Globally, breast cancer is a major reason for female mortality. Due to the limitations of current clinical imaging, the researchers are encouraged to explore alternative and complementary tools to available techniques to detect the breast tumor in an earlier stage. This article outlines a new, portable, and low-cost microwave imaging (MWI) system using an iterative enhancing technique for breast imaging. A compact side slotted tapered slot antenna is designed for microwave imaging. The radiating fins of tapered slot antenna are modified by etching nine rectangular side slots. The irregular slots on the radiating fins enhance the electrical length as well as produce strong directive radiation due to the suppression of induced surface currents that radiate vertically at the outer edges of the radiating arms with end-fire direction. It has remarkable effects on efficiency and gain. With the addition of slots, the side-lobe levels are reduced, the gain of the main-lobe is increased and corrects the squint effects simultaneously, thus improving the characteristics of the radiation. For experimental validation, a heterogeneous breast phantom was developed that contains dielectric properties identical to real breast tissues with the inclusion of tumors. An alternative PC controlled and microcontroller-based mechanical MWI system is designed and developed to collect the antenna scattering signal. The radiated backscattered signals from the targeted area of the human body are analyzed to reveal the changes in dielectric properties in tissues. The dielectric constants of tumorous cells are higher than that of normal tissues due to their higher water content. The remarkable deviation of the scattered field is processed by using newly proposed Iteratively Corrected Delay and Sum (IC-DAS) algorithm and the reconstruction of the image of the phantom interior is done. The developed UWB (Ultra-Wideband) antenna based MWI has been able to perform the detection of tumorous cells in breast phantom that can pave the way to saving lives.
  7. Abdullah JM, Rafiqul Islam M
    Malays J Med Sci, 2012 Oct;19(4):1-5.
    PMID: 23613643
    Telemetric EEG in the rat's brain has been used for experiments which tests the effects of an antiepileptic compound on it's antiseizures activity. A simple classification correlating epileptiform discharge and Racine's behavioral activity is discussed.
  8. Ahsan MR, Islam MT, Habib Ullah M, Misran N
    ScientificWorldJournal, 2014;2014:856504.
    PMID: 24723832 DOI: 10.1155/2014/856504
    A meandered-microstrip fed circular shaped monopole antenna loaded with vertical slots on a high dielectric material substrate (ε r = 15) is proposed in this paper. The performance criteria of the proposed antenna have been experimentally verified by fabricating a printed prototype. The experimental results show that the proposed antenna has achieved wider bandwidth with satisfactory gain by introducing meandered-microstrip feeding in assistant of partial ground plane. It is observed that, the -10 dB impedance bandwidth of the proposed antenna at lower band is 44.4% (600 MHz-1 GHz) and at upper band is 28% (2.25 GHz-2.95 GHz). The measured maximum gains of -1.18 dBi and 4.87 dBi with maximum radiation efficiencies have been observed at lower band and upper band, respectively. The antenna configuration and parametric study have been carried out with the help of commercially available computer-aided EM simulator, and a good accordance is perceived in between the simulated and measured results. The analysis of performance criteria and almost consistent radiation pattern make the proposed antenna a suitable candidate for UHF RFID, WiMAX, and WLAN applications.
  9. Samsuzzaman M, Islam MT, Mandeep JS, Misran N
    ScientificWorldJournal, 2014;2014:804068.
    PMID: 24696661 DOI: 10.1155/2014/804068
    This paper presents a printed wide-slot antenna design and prototyping on available low-cost polymer resin composite material fed by a microstrip line with a rotated square slot for bandwidth enhancement and defected ground structure for gain enhancement. An I-shaped microstrip line is used to excite the square slot. The rotated square slot is embedded in the middle of the ground plane, and its diagonal points are implanted in the middle of the strip line and ground plane. To increase the gain, four L-shaped slots are etched in the ground plane. The measured results show that the proposed structure retains a wide impedance bandwidth of 88.07%, which is 20% better than the reference antenna. The average gain is also increased, which is about 4.17 dBi with a stable radiation pattern in the entire operating band. Moreover, radiation efficiency, input impedance, current distribution, axial ratio, and parametric studies of S11 for different design parameters are also investigated using the finite element method-based simulation software HFSS.
  10. Islam MR, Abdullah JM, Atoji Y
    Anat Histol Embryol, 2013 Aug;42(4):257-65.
    PMID: 22994540 DOI: 10.1111/ahe.12009
    Bioassay and immunohistochemical studies have detected the presence of prosaposin in the central nervous system (CNS) of mammals. Here, first time, we have determined the partial cDNA sequence of pigeon prosaposin and mapped the distribution of its mRNA in the pigeon CNS. The predicted amino acid sequence of pigeon prosaposin showed 93 and 60% identity to chicken and human prosaposin, respectively. In situ hybridization, autoradiograms showed that the prosaposin mRNA expression was found in the olfactory bulb, prepiriform cortex, Wulst, mesopallium, nidopallium, hippocampal formation, thalamus, tuberis nucleus, pre-tectal nucleus, nucleus mesencephalicus lateralis, pars dorsalis, nucleus isthmi, pars parvocellularis and magnocellularis, Edinger-Westphal nucleus, optic tectum, cerebellar cortex and nuclei, vestibular nuclei and gray matter of the spinal cord. These results suggest that the cDNA sequence of pigeon prosaposin is comparable to other vertebrates, and the general distribution pattern of prosaposin mRNA resembles those are found in mammals.
  11. Jawad AH, Azharul Islam M, Hameed BH
    Int J Biol Macromol, 2017 Feb;95:743-749.
    PMID: 27914966 DOI: 10.1016/j.ijbiomac.2016.11.087
    Fabrication of an immobilized cross-linked chitosan-epichlorohydrine thin film (CLCETF) onto glass plate for adsorption of reactive orange 16 (RO16) dye was successfully studied using the direct casting technique. Adsorption experiments were performed as a function of contact time, initial dye concentration (25mg/L to 350mg/L), and pH (3-11). The adsorption isotherm followed the Langmuir model. The adsorption capacity of CLECTF for RO16 was 356.50mg/g at 27±2°C. The kinetics closely followed the pseudo-second-order model. Results supported the potential use of an immobilized CLECTF as effective adsorbent for the treatment of reactive dye without using filtration process.
  12. Rezaul Islam M, Wahab HA, Anggum LA
    Heliyon, 2020 Feb;6(2):e03370.
    PMID: 32072057 DOI: 10.1016/j.heliyon.2020.e03370
    This study aimed to examine the influence of the traditional leadership qualities towards to develop community cohesion in the Iban community in Malaysia. A quantitative approach was used to conduct this study, where data were collected through a self-administered survey questionnaire from 210 chiefs in the Iban longhouse at the Pakan District in Sarawak, Malaysia. A pre-tested questionaire was administrered to the respondents using a simple random sampling in the District of Pakan, Sarawak. The leadership quality was measured based on the leadership traits, leadership style, leadership behaviour, situational leadership, and trsnformational leadership; while the community cohesion was measured by a sense of belonging, social alienation, social support, rootedness, social solidarity, and social ties. The results of the correlation and regression analysis showed that the traditional leadership qualities had a significant correlation with the development of social cohesion. The findings proved that the traditional leadership is essential to increase community cohesion in the Iban community. The findings would be important guideline to the development thinkers, practitioners, community leaders, and development institutions.
  13. Ngozi Nwaefulu O, Rao Sagineedu S, Kaisarul Islam M, Stanslas J
    Eur Rev Med Pharmacol Sci, 2022 Jan;26(2):367-381.
    PMID: 35113412 DOI: 10.26355/eurrev_202201_27861
    OBJECTIVE: Pancreatic cancer (PaCa) is a disease that is extremely difficult to treat and is associated with a high fatality rate. The majority of patients present to hospitals with metastatic or end-stage cancer, making the ultimate cure impossible. End-stage PaCa has no specific treatment, though surgery, irradiation, and chemotherapy can help patients live longer. Consequently, it is vital to accumulate all information on potential targeted therapies for this cancer into a single report.

    MATERIALS AND METHODS: This review has been compiled using relevant keywords and a thorough web search utilising PubMed, ScienceDirect, GoogleScholar, Scopus, MEDLINE, and SpringerLink.

    RESULTS: Conventional medicines that target various biological processes have a significant negative impact on normal cells. As a result, targeted therapies are required, which include the use of small-molecule inhibitors and monoclonal antibodies to target cancer cell surface receptors, growth factors, and other proteins involved in disease progression. In this review, we summarize the known targeted PaCa therapies, which include inhibitors of the KRAS, mTOR, and PI3K/AKT signaling pathways, as well as PARP, hedgehog, EGFR/ErbB, and TGF-β signaling pathways, along with inhibitors of the neurotrophic tropomyosin receptor kinase (NTRK).

    CONCLUSIONS: An adequate understanding of PaCa pathogenesis and the adoption of tailored medicines can increase patients' overall survival. We believe targeted therapy can help patients with PaCa to have a better prognosis. As such, more research is needed to find appropriate biomarkers to aid in early tumor diagnosis and to discover novel prospective therapeutics based on the drugs listed in this article.

  14. Islam M, Mohamed Z, Assenov Y
    Int J Genomics, 2017;2017:2913648.
    PMID: 28713819 DOI: 10.1155/2017/2913648
    Acute myeloid leukemia (AML) is a haematological malignancy characterized by the excessive proliferation of immature myeloid cells coupled with impaired differentiation. Many AML cases have been reported without any known cytogenetic abnormalities and carry no mutation in known AML-associated driver genes. In this study, 200 AML cases were selected from a publicly available cohort and differentially analyzed for genetic, epigenetic, and cytogenetic abnormalities. Three genes (FLT3, DNMT3A, and NPMc) are found to be predominantly mutated. We identified several aberrations to be associated with genome-wide methylation changes. These include Del (5q), T (15; 17), and NPMc mutations. Four aberrations-Del (5q), T (15; 17), T (9; 22), and T (9; 11)-are significantly associated with patient survival. Del (5q)-positive patients have an average survival of less than 1 year, whereas T (15; 17)-positive patients have a significantly better prognosis. Combining the methylation and mutation data reveals three distinct patient groups and four clusters of genes. We speculate that combined signatures have the better potential to be used for subclassification of AML, complementing cytogenetic signatures. A larger sample cohort and further investigation of the effects observed in this study are required to enable the clinical application of our patient classification aided by DNA methylation.
  15. Faruque MR, Islam MT, Misran N
    Med Eng Phys, 2011 Jun;33(5):646-52.
    PMID: 21216175 DOI: 10.1016/j.medengphy.2010.12.004
    The purpose of this paper is to calculate the specific absorption rate (SAR) reduction in a muscle cube with metamaterial attachment. The finite-difference time-domain (FDTD) method has been used to evaluate the SAR in a realistic anatomically based model of the muscle cube. In this paper, we have designed the single-negative metamaterials from a periodic arrangement of split ring resonators (SRRs). By properly designing the structural parameter of the SRRs, the effective medium parameter can be tuned negative at the 900 MHz and 1800 MHz bands. Numerical results concerning the SAR values in the muscle cube in the presence of resonators exhibit significant SAR reduction. These results can provide useful information when designing safety-compliant mobile communication equipment.
  16. Hassan HA, Muhammed SS, Al-Khdhairawi A, Abdelwahab SF, Abdel-Rahman IM, Abdelhamid MM
    J Biomol Struct Dyn, 2023 Aug 16.
    PMID: 37584104 DOI: 10.1080/07391102.2023.2246563
    Extracellular signal-regulated kinase 2 (ERK-2) is a serine/threonine protein kinase in eukaryotic cells and belongs to the mitogen-activated protein kinase (MAPK) family. An activated form of ERK-2 phosphorylates substrates in the nucleus or cytoplasm and causes specific proteins to be expressed or activated, regulating cell proliferation, differentiation and other functions. Caffeic acid (3,4 - dihydroxy cinnamic acid), as previously reported, directly interacts with ERK-2 and reduces its effects in vitro. It is also reported to have a variety of pharmacological effects, including anti-inflammatory, immunomodulatory, antioxidant and anticancer activities. In the current study, a deep-learning protocol was employed to develop effective 100 compounds by modifying the chemical structure of DHC to improve its inhibitory performance against ERK-2. Calculations of physicochemical properties for those compounds revealed that 20 compounds had drug scores better than DHC (≥ 80%). Following that, molecular docking calculations were performed on the selected compounds and DHC. The obtained data revealed that five compounds had docking scores better than DHC (≥ -5.9 kcal/mol). Moreover, data from molecular mechanics and the Poisson - Boltzmann surface area (MM/PBSA) binding energy over 200 ns MD simulation confirmed that Cmd-1 and Cmd-4 exhibited higher stability with ΔGbinding of -40.8 and -49.1 kcal/mol, respectively, which is better than DHC (-35.1 kcal/mol). Finally, various energetic and structural studies showed the high stability of the two generated compounds within the active site of ERK-2. This study highlights the potential use of Cmd-1 and Cmd-4 as promising anti-ERK-2 drug candidates.Communicated by Ramaswamy H. Sarma.
  17. Samiul Islam M, Sobayel K, Al-Kahtani A, Islam MA, Muhammad G, Amin N, et al.
    Nanomaterials (Basel), 2021 May 05;11(5).
    PMID: 34063020 DOI: 10.3390/nano11051218
    Recent achievements, based on lead (Pb) halide perovskites, have prompted comprehensive research on low-cost photovoltaics, in order to avoid the major challenges that arise in this respect: Stability and toxicity. In this study, device modelling of lead (Pb)-free perovskite solar cells has been carried out considering methyl ammonium tin bromide (CH3NH3SnBr3) as perovskite absorber layer. The perovskite structure has been justified theoretically by Goldschmidt tolerance factor and the octahedral factor. Numerical modelling tools were used to investigate the effects of amphoteric defect and interface defect states on the photovoltaic parameters of CH3NH3SnBr3-based perovskite solar cell. The study identifies the density of defect tolerance in the absorber layer, and that both the interfaces are 1015 cm-3, and 1014 cm-3, respectively. Furthermore, the simulation evaluates the influences of metal work function, uniform donor density in the electron transport layer and the impact of series resistance on the photovoltaic parameters of proposed n-TiO2/i-CH3NH3SnBr3/p-NiO solar cell. Considering all the optimization parameters, CH3NH3SnBr3-based perovskite solar cell exhibits the highest efficiency of 21.66% with the Voc of 0.80 V, Jsc of 31.88 mA/cm2 and Fill Factor of 84.89%. These results divulge the development of environmentally friendly methyl ammonium tin bromide perovskite solar cell.
  18. Faruque MR, Hossain MI, Misran N, Singh M, Islam MT
    PLoS One, 2015;10(11):e0142663.
    PMID: 26599584 DOI: 10.1371/journal.pone.0142663
    A metamaterial-embedded planar inverted-F antenna (PIFA) is proposed in this study for cellular phone applications. A dual-band PIFA is designed to operate both GSM 900 MHz and DCS 1800 MHz. The ground plane of a conventional PIFA is modified using a planar one-dimensional metamaterial array. The investigation is performed using the Finite Integration Technique (FIT) of CST Microwave Studio. The performance of the developed antenna was measured in an anechoic chamber. The specific absorption rate (SAR) values are calculated considering two different holding positions: cheek and tilt. The SAR values are measured using COMOSAR measurement system. Good agreement is observed between the simulated and measured data. The results indicate that the proposed metamaterial-embedded antenna produces significantly lower SAR in the human head compared to the conventional PIFA. Moreover, the modified antenna substrate leads to slight improvement of the antenna performances.
  19. Islam MJ, Reza AW, Kausar AS, Ramiah H
    ScientificWorldJournal, 2014;2014:306270.
    PMID: 25133220 DOI: 10.1155/2014/306270
    The advent of technology with the increasing use of wireless network has led to the development of Wireless Body Area Network (WBAN) to continuously monitor the change of physiological data in a cost efficient manner. As numerous researches on wave propagation characterization have been done in intrabody communication, this study has given emphasis on the wave propagation characterization between the control units (CUs) and wireless access point (AP) in a hospital scenario. Ray tracing is a tool to predict the rays to characterize the wave propagation. It takes huge simulation time, especially when multiple transmitters are involved to transmit physiological data in a realistic hospital environment. Therefore, this study has developed an accelerated ray tracing method based on the nearest neighbor cell and prior knowledge of intersection techniques. Beside this, Red-Black tree is used to store and provide a faster retrieval mechanism of objects in the hospital environment. To prove the superiority, detailed complexity analysis and calculations of reflection and transmission coefficients are also presented in this paper. The results show that the proposed method is about 1.51, 2.1, and 2.9 times faster than the Object Distribution Technique (ODT), Space Volumetric Partitioning (SVP), and Angular Z-Buffer (AZB) methods, respectively. To show the various effects on received power in 60 GHz frequency, few comparisons are made and it is found that on average -9.44 dBm, -8.23 dBm, and -9.27 dBm received power attenuations should be considered when human, AP, and CU move in a given hospital scenario.
  20. Samsuzzaman M, Islam MT, Arshad H, Mandeep JS, Misran N
    ScientificWorldJournal, 2014;2014:345190.
    PMID: 24982943 DOI: 10.1155/2014/345190
    Circularly polarized (CP) dual frequency cross-shaped slotted patch antenna on 1.575 mm thick glass microfiber reinforced polytetrafluoroethylene (PTFE) composite material substrate is designed and fabricated for satellite applications. Asymmetric cross-shaped slots are embedded in the middle of the square patch for CP radiation and four hexagonal slots are etched on the four sides of the square patch for desired dual frequency. Different substrate materials have been analysed to achieve the desired operating band. The experimental results show that the impedance bandwidth is approximately 30 MHz (2.16 GHz to 2.19 GHz) for lower band and 40 MHz (3.29 GHz to 3.33 GHz) for higher band with an average peak gain of 6.59 dBiC and 5.52 dBiC, respectively. Several optimizations are performed to obtain the values of the antenna physical parameters. Moreover, the proposed antenna possesses compactness, light weight, simplicity, low cost, and circularly polarized. It is an attractive candidate for dual band satellite antennas where lower band can be used for uplink and upper band can be used for downlink.
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