Displaying publications 1101 - 1120 of 1808 in total

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  1. Wan KS, Hairi NN, Mustapha F, Ismail M, Mohd Yusoff MF, Moy FM
    PeerJ, 2022;10:e13816.
    PMID: 36317122 DOI: 10.7717/peerj.13816
    BACKGROUND: Patients with diabetes have increased risks of cardiovascular diseases (CVD), and their LDL-cholesterol (LDL-C) has to be treated to target to prevent complications. We aim to determine the LDL-C trend and its predictors among patients with type 2 diabetes (T2D) in Malaysia.

    METHODS: This was a retrospective open cohort study from 2013 to 2017 among T2D patients in public primary health care clinics in Negeri Sembilan state, Malaysia. Linear mixed-effects modelling was conducted to determine the LDL-C trend and its predictors. The LDL-C target for patients without CVD was <2.6 mmol/L, whereas <1.8 mmol/L was targeted for those with CVD.

    RESULTS: Among 18,312 patients, there were more females (55.9%), adults ≥60 years (49.4%), Malays (64.7%), non-smokers (93.6%), and 45.3% had diabetes for <5 years. The overall LDL-C trend reduced by 6.8% from 2.96 to 2.76 mmol/L. In 2017, 16.8% (95% CI: 13.2-21.0) of patients without CVD and 45.8% (95% CI: 44.8-46.8) of patients with CVD achieved their respective LDL-C targets. The predictors for a higher LDL-C trend were younger adults, Malay and Indian ethnicities, females, dyslipidemia, and diabetes treatment with lifestyle modification and insulin. Longer diabetes duration, obesity, hypertension, retinopathy, statin therapy, achievement of HbA1c target and achievement of BP target were independent predictors for a lower LDL-C trend.

    CONCLUSIONS: The LDL-C trend has improved, but there are still gaps between actual results and clinical targets. Interventions should be planned and targeted at the high-risk populations to control their LDL-C.

  2. Meena RAA, Sathishkumar P, Ameen F, Yusoff ARM, Gu FL
    Environ Sci Pollut Res Int, 2018 Feb;25(5):4134-4148.
    PMID: 29247419 DOI: 10.1007/s11356-017-0966-2
    With growing population and urbanization, there is an increasing exploitation of natural resources, and this often results to environmental pollution. In this review, the levels of heavy metal in lentic compartments (water, sediment, fishes, and aquatic plants) over the past two decades (1997-2017) have been summarized to evaluate the current pollution status of this ecosystem. In all the compartments, the heavy metals dominated are zinc followed by iron. The major reason could be area mineralogy and lithogenic sources. Enormous quantity of metals like iron in estuarine sediment is a very natural incident due to the permanently reducing condition of organic substances. Contamination of cadmium, lead, and chromium was closely associated with anthropogenic origin. In addition, surrounding land use and atmospheric deposition could have been responsible for substantial pollution. The accumulation of heavy metals in fishes and aquatic plants is the result of time-dependent deposition in lentic ecosystems. Moreover, various potential risk assessment methods for heavy metals were discussed. This review concludes that natural phenomena dominate the accumulation of essential heavy metals in lentic ecosystems compared to anthropogenic sources. Amongst other recent reviews on heavy metals from other parts of the world, the present review is executed in such a way that it explains the presence of heavy metals not only in water environment, but also in the whole of the lentic system comprising sediment, fishes, and aquatic plants.
  3. Kasavan S, Yusoff S, Guan NC, Zaman NSK, Fakri MFR
    Environ Sci Pollut Res Int, 2021 Sep;28(33):44780-44794.
    PMID: 34235692 DOI: 10.1007/s11356-021-15303-5
    Researchers have broadly studied textile waste, but the research topics development and performance trends in this study area are still unclear. A bibliometric analysis was conducted to explore the global scientific literature to determine state of the art on textile waste over the past 16 years. Data of publications output are identified based on the Web of Science (from 2015 to 2020). This study used VOSviewer to analyse collaboration networks among authors, countries, institutions, and author's keywords in identifying five main clusters. A total of 3296 papers in textile waste research were identified. In this study, a total of 10451 authors were involved in textile waste research, and 36 authors among them published more than ten research publications in the period of this study. China has been in a top position in textile waste research moving from 3 output publications in 2005 to 91 output publications in 2020. Indian Institute of Technology System IIT System was ranked first in terms of the total publication number (85 publications, 2.45%). Textile wastewater and adsorption are the most commonly used keywords that reflect the current main research direction in this field and received more attention in recent years. Based on keyword cluster analysis outputs, textile waste research can be categorized into five types of clusters, namely (1) pollutant compositions, (2) component of textile wastewater, (3) treatment methods for textile wastewater, (4) effect mechanism of textile wastewater, and (5) recyclability of textile waste.
  4. Khan AM, Yusoff I, Bakar NKA, Bakar AFA, Alias Y
    Environ Sci Pollut Res Int, 2016 Dec;23(24):25039-25055.
    PMID: 27677993 DOI: 10.1007/s11356-016-7641-x
    A study was carried out to determine the level of rare earth elements (REEs) in water and sediment samples from ex-mining lakes and River in Kinta Valley, Perak, Malaysia. Surface water and sediments from an ex-mining lake and Kinta River water samples were analyzed for REEs by inductively coupled plasma mass spectrometry. The total concentration of REEs in the ex-mining lake water samples and sediments were found to be 3685 mg/l and 14159 mg/kg, respectively, while the total concentration of REEs in Kinta River water sample was found to be 1224 mg/l. REEs in mining lake water were found to be within 2.42 mg/l (Tb) to 46.50 mg/l (Ce), while for the Kinta River, it was 1.33 mg/l (Ho) to 29.95 mg/l (Ce). Sediment samples were also found with REEs from 9.81 mg/kg (Ho) to 765.84 mg/kg (Ce). Ce showed the highest average concentrations for mining lake (3.88 to 49.08 mg/l) and Kinta River (4.44 to 33.15 mg/l) water samples, while the concentration of La was the highest (11.59 to 771.61 mg/kg) in the mining lake sediment. Lu was shown to have the highest enrichment of REEs in ex-mining lake sediments (107.3). Multivariate statistical analyses such as factor analysis and principal component analysis indicated that REEs were associated and controlled by mixed origin, with similar contributions from anthropogenic and geogenic sources. The speciation study of REEs in ex-tin mining sediments using a modified five-stage sequential extraction procedure indicated that yttrium (Y), gadolinium (Gd), and lanthanum (La) were obtained at higher percentages from the adsorbed/exchanged/carbonate fraction. The average potential mobility of the REEs was arranged in a descending order: Yb > Gd > Y = Dy > Pr > Er > Tm > Eu > Nd > Tb > Sc > Lu > Ce > La, implying that under favorable conditions, these REEs could be released and subsequently pollute the environment.
  5. Kamaruddin MA, Yusoff MS, Rui LM, Isa AM, Zawawi MH, Alrozi R
    Environ Sci Pollut Res Int, 2017 Dec;24(35):26988-27020.
    PMID: 29067615 DOI: 10.1007/s11356-017-0303-9
    Currently, generation of solid waste per capita in Malaysia is about 1.1 kg/day. Over 26,500 t of solid waste is disposed almost solely through 166 operating landfills in the country every day. Despite the availability of other disposal methods, landfill is the most widely accepted and prevalent method for municipal solid waste (MSW) disposal in developing countries, including Malaysia. This is mainly ascribed to its inherent forte in terms cost saving and simpler operational mechanism. However, there is a downside. Environmental pollution caused by the landfill leachate has been one of the typical dilemmas of landfilling method. Leachate is the liquid produced when water percolates through solid waste and contains dissolved or suspended materials from various disposed materials and biodecomposition processes. It is often a high-strength wastewater with extreme pH, chemical oxygen demand (COD), biochemical oxygen demand (BOD), inorganic salts and toxicity. Its composition differs over the time and space within a particular landfill, influenced by a broad spectrum of factors, namely waste composition, landfilling practice (solid waste contouring and compacting), local climatic conditions, landfill's physico-chemical conditions, biogeochemistry and landfill age. This paper summarises an overview of landfill operation and leachate treatment availability reported in literature: a broad spectrum of landfill management opportunity, leachate parameter discussions and the way forward of landfill leachate treatment applicability.
  6. Jumin E, Basaruddin FB, Yusoff YBM, Latif SD, Ahmed AN
    Environ Sci Pollut Res Int, 2021 Jun;28(21):26571-26583.
    PMID: 33484461 DOI: 10.1007/s11356-021-12435-6
    Reliable and accurate prediction model capturing the changes in solar radiation is essential in the power generation and renewable carbon-free energy industry. Malaysia has immense potential to develop such an industry due to its location in the equatorial zone and its climatic characteristics with high solar energy resources. However, solar energy accounts for only 2-4.6% of total energy utilization. Recently, in developed countries, various prediction models based on artificial intelligence (AI) techniques have been applied to predict solar radiation. In this study, one of the most recent AI algorithms, namely, boosted decision tree regression (BDTR) model, was applied to predict the changes in solar radiation based on collected data in Malaysia. The proposed model then compared with other conventional regression algorithms, such as linear regression and neural network. Two different normalization techniques (Gaussian normalizer binning normalizer), splitting size, and different input parameters were investigated to enhance the accuracy of the models. Sensitivity analysis and uncertainty analysis were introduced to validate the accuracy of the proposed model. The results revealed that BDTR outperformed other algorithms with a high level of accuracy. The funding of this study could be used as a reliable tool by engineers to improve the renewable energy sector in Malaysia and provide alternative sustainable energy resources.
  7. Qureshi MI, Yusoff RM, Hishan SS, Alam AF, Zaman K, Rasli AM
    Environ Sci Pollut Res Int, 2019 May;26(15):15496-15509.
    PMID: 30937745 DOI: 10.1007/s11356-019-04866-z
    The natural catastrophic events largely damage the country's sustainability agenda through massive human fatalities and infrastructure destruction. Although it is partially supported the economic growth through the channel of "Schumpeter creative destruction" hypothesis, however, it may not be sustained in the long-run. This study examined the long-run and causal relationships between natural disasters (i.e., floods, storm, and epidemic) and per capita income by controlling FDI inflows and foreign aid in the context of Malaysia, during the period of 1965-2016. The study employed time series cointegration technique, i.e., autoregressive distributed lag (ARDL)-bounds testing approach for robust inferences. The results show that flood, storm, and epidemic disasters substantially decrease the country's per capita income, while FDI inflows and foreign aid largely supported the country's economic growth in the short-run. These results are disappeared in the long-run, where flood and storm disasters exhibit the positive association with the economic growth to support the Schumpeter creative destruction hypothesis. The foreign aid decreases the per capita income and does not maintain the "aid-effectiveness" hypotheses in a given country. The causality estimates confirmed the disaster-led growth hypothesis, as the causality estimates running from (i) storm to per capita income, (ii) epidemic to per capita income, and (iii) storm to foreign aid. The results emphasized for making disaster action plans to reduce human fatalities and infrastructure for sustainable development.
  8. Alwi A, Zulkifli NW, Sukiman NL, Yusoff A, Zakaria Z, Jamshaid M, et al.
    Environ Sci Pollut Res Int, 2019 Apr;26(12):11815-11826.
    PMID: 30811022 DOI: 10.1007/s11356-019-04603-6
    The availability of natural energy resources and the environmental issues are the most significant issues that are often highlighted by the world communities. With regard to these problems, isobutanol is a higher chain alcohol with four carbons which can be derived from biomass resources and it is potential to become an alternative fuel source besides the biodiesel for a diesel engine. The aim of this study is to evaluate the effect of isobutanol with Calophyllum inophyllum methyl ester and diesel as the ternary blend on physicochemical properties, engine performance, and emission characteristics. Five different fuel blends containing Calophyllum inophyllum biodiesel and isobutanol were tested on a single-cylinder direct injection diesel engine at different engine load of brake mean effective pressure. The physicochemical properties of the fuel blends were measured and then compared with neat diesel. The results indicate that the blend containing isobutanol and CIME gives a slight increase in BSEC and EGT and a minimal drop in BTE as compared to that of neat diesel. Besides that, the tested blends show a reduction of carbon monoxide and unburned hydrocarbon emissions. Meanwhile, all the fuel blends show a minimal increase in carbon dioxide and nitrogen oxides emissions, compared to that of neat diesel. Isobutanol can be proved as a preferred substitute for biodiesel and diesel fuels to achieve desired engine performance and emissions level.
  9. Khahro SH, Memon ZA, Yusoff NIM, Gungat L, Yazid MRM
    Environ Sci Pollut Res Int, 2022 Feb;29(7):10771-10781.
    PMID: 34613546 DOI: 10.1007/s11356-021-16499-2
    Roads play a pivotal role in the overall economic growth of any country. Developed countries allocated sufficient budget to make new roads and to maintain the existing roads. They also have a proper pavement management system (PMS) in practice to manage roads, whereas developing countries suffer from budgetary issues to make new roads and maintain the existing road network. Therefore, this paper explores the awareness of PMS via direct and indirect methods in Pakistan with a proposed framework of the low-cost model and pavement maintenance indicators for developing countries. This paper also performs a scientometric assessment of PMS. A detailed literature review has been carried out for this study, followed by a quantitative study from experienced professionals. The scientometric data is collected from the Scopus database from 1975 to 2020, whereas the data for PMS awareness assessment has been collected using questionnaires from different experts working directly and indirectly in the road management sector. The data has been analyzed using the arithmetic mean because of the nature of the questions and scope of the study. The direct method results show that experts are aware of PMS for a new road, but they have no PMS to rehabilitate roads. The indirect method results show that the authorities are applying various components of PMS, but there is no proper PMS in practice. This paper helps decision-makers to make better decisions and policies for improved road maintenance and rehabilitation. The proposed framework in the study can significantly assist the UN-SDG 9 (Facilitate Sustainable Infrastructure in Developing Countries) and 11 (Affordable and Sustainable Transport System).
  10. Wadi MM, Yusoff MSB, Taha MH, Shorbagi S, Nik Lah NAZ, Abdul Rahim AF
    BMC Med Educ, 2023 Apr 05;23(1):213.
    PMID: 37016407 DOI: 10.1186/s12909-023-04177-5
    BACKGROUND: Burnout and depression among health professions education (HPE) students continue to rise, leading to unwanted effects that ultimately jeopardise optimal medical care and patient health. Promoting the resilience of medical students is one solution to this issue. Several interventions have been implemented to foster resilience, but they focus on aspects other than the primary cause: the assessment system. The purpose of this study is to develop a framework to promote resilience in assessment planning and practice.

    METHODS: We followed the guidelines suggested by Whetten for constructing a theoretical model for framework development. There were four phases in the model development. In the first phase, different literature review methods were used, and additional students' perspectives were collected through focus group discussions. Then, using the data, we constructed the theoretical model in the second phase. In the third phase, we validated the newly developed model and its related guidelines. Finally, we performed response process validation of the model with a group of medical teachers.

    RESULTS: The developed systematic assessment resilience framework (SAR) promotes four constructs: self-control, management, engagement, and growth, through five phases of assessment: assessment experience, assessment direction, assessment preparation, examiner focus, and student reflection. Each phase contains a number of practical guidelines to promote resilience. We rigorously triangulated each approach with its theoretical foundations and evaluated it on the basis of its content and process. The model showed high levels of content and face validity.

    CONCLUSIONS: The SAR model offers a novel guideline for fostering resilience through assessment planning and practice. It includes a number of attainable and practical guidelines for enhancing resilience. In addition, it opens a new horizon for HPE students' future use of this framework in the new normal condition (post COVID 19).

  11. Wadi M, Yusoff MSB, Abdul Rahim AF, Lah NAZN
    BMC Psychol, 2022 Jan 06;10(1):8.
    PMID: 34991718 DOI: 10.1186/s40359-021-00715-2
    BACKGROUND: Medical students are vulnerable to test anxiety (TA), which impacts their professional lives and jeopardizes the optimal health care of their patients. The qualitative exploration of TA among medical students is crucial to understanding the problem. Hence, this study examined medical students' insights into TA and their suggestions on how to reduce it.

    METHODS: We conducted a phenomenological study on medical students at a public university. We utilized focus group discussions (FGDs) to investigate their experiences of TA. The FGDs were transcribed verbatim, and these transcripts were analyzed using Atlas.ti software. The thematic analysis followed the recommended guidelines.

    RESULTS: Seven FGD sessions were conducted with 45 students. Three major themes emerged: the students, their academic resources, and the examiner. Each theme comprised mutually exclusive subthemes. The "students" theme was divided into negative vs. positive thoughts and self-negligence vs. self-care, "academic recources" into heavy curriculum vs. facilitative curricular aids, and "examiner" into criticism vs. feedback and strict vs. kind approaches.

    CONCLUSION: This study provides a solid foundation for policymakers and decision makers in medical education to improve current assessment practices and student well-being. Medical students will be able to significantly alter and reduce TA if they are provided with additional psychological support and their examiners are trained on how to deal with examinees.

  12. Guraya SS, Guraya SY, Harkin DW, Ryan Á, Mat Nor MZB, Yusoff MSB
    Med Educ Online, 2021 Dec;26(1):1983926.
    PMID: 34775927 DOI: 10.1080/10872981.2021.1983926
    BACKGROUND: Medical professionalism education intends to produce virtuous and humanistic healthcare professionals who demonstrate perseverance and professional integrity. However, today's medicine has embodied a mammoth transformation of medical practice towards sns and the digital realm. Such paradigm shift has challenged the medical professional's values, behaviors, and identities, and the distinct boundaries between personal and professional lives are blurred. This study aims to develop a framework for healthcare professionals coping with the challenges of medical professionalism in the digital realm.

    METHODS: We followed a systematic approach for the development of a framework about e-professionalism. Qualitative data was collected from a systematic review and a delphi study, while quantitative data was collected by administering a validated questionnaire social networking sites for medical education (snsme). Subsequently, categorization of the selected data and identifying concepts, deconstruction and further categorizing concepts (philosophical triangulation), integration of concepts (theoretical triangulation), and synthesis and resynthesis of concepts were performed.

    RESULTS: The initial process yielded six overlapping concepts from personal, professional, character (implicit) and characteristic (explicit) domains: environment, behavior, competence, virtues, identity, and mission. Further integration of data was done for the development of the medical education e-professionalism (meep) framework with a central concept of a commitment to mission. The mission showed deep connections with values (conformity, beneficence, universalism, and integrity), behaviours (communication, self-awareness, tolerance, power), and identity (reflection, conscientiousness, self-directed, self-actualization). The data demonstrated that all medical professionals require updated expertise in sns participation.

    CONCLUSION: The meep framework recognises a mission-based social contract by the medical community. This mission is largely driven by professional values, behaviors and identity. Adherence to digital standards, accountability, empathy, sensitivity, and commitment to society are essential elements of the meep framework.

  13. Wan Yusoff WSY, Abdul Zuki FA, Abu MN, Md Saad WM
    J Cytol, 2024;41(2):75-83.
    PMID: 38779605 DOI: 10.4103/joc.joc_110_23
    BACKGROUND AND OBJECTIVE: Trichomonas vaginalis is a causative agent of trichomoniasis, a sexually transmitted disease. In the cytology course context, students are taught to identify the cytomorphological characteristics of this organism. However, the limited learning period hinders their ability to recognize this infection effectively. This study intended to evaluate the efficacy of gamification by utilizing a web-based online game to enhance students' capacity to recognize Trichomonas vaginalis infection in cytology.

    MATERIALS AND METHODS: The study involved 50 Medical Laboratory Technology students who were randomly assigned to three groups. Group 1 (G1) participants received an interactive web-based online game called CytoUniverse, which comprised three components: a story-based game, a cytomorphology game, and a quiz focusing on Trichomonas vaginalis infection in cytology. Group 2 (G2) participants received the same information from a video lecture. Group 3 (G3) received both the web-based online game and the video lecture. The participants were assessed before the intervention (T1) and after the intervention (T2) to measure the effectiveness of the respective learning methods. IBM SPSS version 28 and GraphPad Prism version 9.0 were used to collect, tabulate, and analyze the data. By using descriptive analysis, the normality of the data was checked. Knowledge score and age were described as mean and standard deviation (SD) for numerical data. On the contrary, the categorical data, such as gender and group categories, were reported as frequencies and percentages. Fisher's exact test, paired t-test, and one-way ANOVA test were used in this study to determine the significance between groups.

    RESULTS: The study's results indicated a statistically significant improvement (P < 0.05) in knowledge scores at T2 compared to T1 for both G1 and G2 when compared to G3. However, there were no significant differences in knowledge scores between all groups for T1 or T2.

    CONCLUSIONS: In conclusion, gamification through a web-based online game may improve understanding of Trichomonas vaginalis infection. It looks to be a promising strategy for boosting students' knowledge and awareness to recognize Trichomonas vaginalis infection in cytology.

  14. Razak MR, Wee SY, Yusoff FM, Yusof ZNB, Aris AZ
    Environ Res, 2024 May 03;252(Pt 3):119045.
    PMID: 38704014 DOI: 10.1016/j.envres.2024.119045
    Endocrine disrupting compounds (EDCs) pose a significant ecological risk, particularly in aquatic ecosystems. EDCs have become a focal point in ecotoxicology, and their identification and regulation have become a priority. Zooplankton have gained global recognition as bioindicators, benefiting from rigorous standardization and regulatory validation processes. This review aims to provide a comprehensive summary of zooplankton-based adverse outcome pathways (AOPs) with a focus on EDCs as toxicants and the utilisation of freshwater zooplankton as bioindicators in ecotoxicological assessments. This review presents case studies in which zooplankton have been used in the development of AOPs, emphasizing the identification of molecular initiating events (MIEs) and key events (KEs) specific to zooplankton exposed to EDCs. Zooplankton-based AOPs may become an important resource for understanding the intricate processes by which EDCs impair the endocrine system. Furthermore, the data sources, experimental approaches, advantages, and challenges associated with zooplankton-based AOPs are discussed. Zooplankton-based AOPs framework can provide vital tools for consolidating toxicological knowledge into a structured toxicity pathway of EDCs, offering a transformative platform for facilitating enhanced risk assessment and chemical regulation.
  15. Iorember PT, Mohamed Yusoff NY, Abachi PT, Usman O, Alola AA
    Heliyon, 2024 May 15;10(9):e30138.
    PMID: 38707373 DOI: 10.1016/j.heliyon.2024.e30138
    The agricultural value chain is underpinned by the interdependence of agricultural value added, household consumption and domestic investment. Understanding the complex interactions between these microeconomic outcomes and the uncertainties in the macroeconomic variables of exchange rates, energy prices and sectoral spending remains under-researched. Therefore, this study examines the impact of exchange rate, energy prices and sectoral spending on agricultural value added, household consumption and domestic investment in Nigeria from 1981 to 2020. Using Kernel regularized least squares (KRLS), the results show that the average pointwise marginal effects of exchange rate and agricultural spending are positive, while the average pointwise marginal effect of energy price is significantly negative for the agricultural value-added model. The results also show that the exchange rate, energy prices and agricultural expenditure all have a positive effect on household consumption. Regarding domestic investment, the effect of the exchange rate is positive and statistically insignificant, while the effects of energy prices and agricultural expenditure are negative and statistically significant. The study recommends the need to strengthen the social safety nets currently in place in Nigeria to support households that are vulnerable to exchange rate fluctuations. In addition, incentives should be given to households and farmers to help use renewable energy sources such as solar or wind power for agricultural activities. Also, investment in value chains and agribusiness initiatives should be encouraged rather than just in crop production.
  16. Tan YP, Ling TC, Tan WS, Yusoff K, Tey BT
    Protein Expr Purif, 2006 Mar;46(1):114-21.
    PMID: 16139513
    In the present work, a single-step purification of recombinant nucleocapsid protein (NP) of the Newcastle disease virus (NDV) directly from unclarified feedstock using an expanded bed adsorption chromatography (EBAC) was developed. Streamline 25 column (ID = 25 mm) was used as a contactor and Streamline chelating adsorbent immobilized with Ni2+ ion was used as affinity adsorbent. The dynamic binding capacity of Ni2+ -loaded Streamline chelating adsorbent for the NP protein in unclarified feedstock was found to be 2.94 mg ml(-1) adsorbent at a superficial velocity of 200 cm h(-1). The direct purification of NP protein from unclarified feedstock using expanded bed adsorption has resulted in a 31% adsorption and 9.6% recovery of NP protein. The purity of the NP protein recovered was about 70% and the volume of processing fluid was reduced by a factor of 10. The results of the present study show that the IMA-EBAC developed could be used to combine the clarification, concentration and initial purification steps into a single-step operation.
  17. Musaed AA, Al-Bawri SS, Abdulkawi WM, Aljaloud K, Yusoff Z, Islam MT
    Sci Rep, 2024 Jan 02;14(1):290.
    PMID: 38168653 DOI: 10.1038/s41598-023-50544-z
    A 16-port massive Multiple-Input-Multiple-Output (mMIMO) antenna system featuring a high gain and efficiency is proposed for millimeter-wave applications. The antenna system consists of 64 elements with a total size of 17 λo × 2.5λo, concerning the lowest frequency. Each 2 × 2 (radiating patch) subarray is designed to operate within the 25.5-29 GHz frequency range. The antenna's performance in terms of isolation, gain, and efficiency has been significantly improved by utilizing the proposed unique double and epsilon negative (DNG/ENG) metamaterials. The array elements are positioned on top of a Rogers RT5880 substrate, with ENG metamaterial unit cells interposed in between to mitigate coupling effects. Additionally, the DNG metamaterial reflector is positioned at the rear of the antenna to boost the gain. As a result, the metamaterial-based mMIMO antenna offers lower measured isolation reaching 25 dB, a maximum gain of 20 dBi and an efficiency of up to 99%. To further analyze the performance of the MIMO antenna, the diversity gain and enveloped correlation coefficient are discussed in relation to the MIMO parameters.
  18. Choo SW, Yusoff AM, Wong YL, Wee WY, Ong CS, Ng KP, et al.
    J Bacteriol, 2012 Sep;194(18):5128.
    PMID: 22933758 DOI: 10.1128/JB.01096-12
    The genome of Mycobacterium massiliense M172, isolated from a human sputum sample, was sequenced using Illumina GA IIX technology and found to contain 5,204,460 bp, including putative genes for virulence and antibiotic resistance as well as a 92-kb genomic region most likely to correspond to a mycobacteriophage.
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