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Catechin-rich oil palm leaf extract enhances bone calcium content of estrogen-deficient rats

Bakhsh A, Mustapha NM, Mohamed S

Nutrition, 2013 Apr;29(4):667-72.
PMID: 23290096 DOI: 10.1016/j.nut.2012.09.005

Postmenopausal estrogen deficiency often causes bone density loss and osteoporosis. This study evaluated the effects of an oral administration of oil palm leaf extract (OPL) on bone calcium content and structure, bone density, ash weights, and serum total alkaline phosphatase (T-ALP) of estrogen-deficient ovariectomized (OVX) rats.
Ficus carica and bone health: a systematic review

Ruszymah Idrus, Nur Qisya Afifah Veronica Sainik, Ayu Suraya Ansari, Rabiatul Adawiyah Razali, Abid Nordin, Aminuddin Saim, et al.

Sains Malaysiana, 2018;47:2741-2755.

Ficus carica, a native plant to the Middle East and Western Asia, is of high value in folk medicine. The therapeutic potential
of Ficus carica has led to the extensive studies in recent years, focusing on evaluating and validating its pharmacological
effect. The present systematic review summarizes the effectiveness of Ficus carica on promoting bone health focusing on
osteoporosis and rheumatoid arthritis via mineral contents and RANKL pathway. The search was done with Medline via
Ebscohost, Scopus and Google Scholar databases to obtain relevant articles published between 1946 and December
2016. The main inclusion criteria were research articles published in English that reported effect of Ficus carica on
bone health. The literature search returned 716 potentially relevant articles, whereby 5 met the inclusion criteria. This
systematic review concludes Ficus carica plays an important role in the promotion of bone health and can be a potential
pharmaceutical product in the future.
Scopoletin-standardized Morinda elliptica leaf extract suppressed inflammation and cartilage degradation to alleviate osteoarthritis: A preclinical study

Wan Osman WN, Lau SF, Mohamed S

Phytother Res, 2017 Dec;31(12):1954-1961.
PMID: 29067744 DOI: 10.1002/ptr.5949

The effect of scopoletin-standardized Morinda elliptica leaf extract against osteoarthritis was investigated in ex vivo explant culture and preclinical rodent model. Thirty male rats were grouped (n = 6) into untreated osteoarthritis (OA), OA + Diclofenac (5 mg/kg), and OA + extract (200 and 400 mg/kg) and compared with healthy control. Monosodium iodoacetate were injected into the right intra-articular knee joints to induce OA. The rats were evaluated for OA severity via physical (micro-CT and histological observations), biochemical, ELISA, and mRNA expression analysis (for inflammation and cartilage degradation biomarkers), after 28 days of treatment. The extract suppressed glycosaminoglycan release from the cartilage explant in the presence of Interleukin-1β. The 200 mg/kg dose appeared better than 400 mg/kg dose, at reducing cartilage and subchondral bone erosions in OA-induced rats, by significantly down-regulating the collagenases and aggrecanase. The extract dose-dependently reduced serum inflammation biomarkers and increased bone formation biomarkers to near normal levels in the OA-induced rats. M. elliptica leaf scopoletin-standardised extract alleviated OA progression and articular cartilage structure, by ameliorating cartilage degradation, nitric oxide levels, inflammation, bone /cartilage homeostasis, collagenase/aggrecanase activities, chondrocytes survival, subchondral bone structure and integrity.
Orthosiphon stamineus (Misai Kucing) ameliorated postmenopausal osteoporosis in rat model

Bokhari RA, Lau SF, Mohamed S

Menopause, 2018 02;25(2):202-210.
PMID: 28926512 DOI: 10.1097/GME.0000000000000980

OBJECTIVE: Orthosiphon stamineus (OS) or Misai Kucing (Java tea) is a popular herbal supplement from Southeast Asia for various metabolic, age-related diseases. This study investigated the potential use of OS leaf extracts to ameliorate osteoporosis in ovariectomized rats.
METHODS: Fifty-six female Sprague-Dawley rats were randomly allocated into eight groups (n = 7): SHAM (healthy sham control); OVX (ovarietomized) nontreated rats (negative control); OVX + Remifemin (100 mg/kg body weight), and 2% green tea extract (positive controls); OVX + OS 50% ethanolic and aqueous extracts, both at either 150 or 300 mg/kg. After 16 weeks, the rats' bones and blood were evaluated for osteoporosis indicators (protein and mRNA expressions), micro-computed tomography for bone histomorphometry, and three-point bending test for tibia mechanical strength.
RESULTS: The extracts dose-dependently and significantly (P
Fulltext Cytomegalovirus Retinitis in Primary Immune Deficiency Disease

Ngai JJ, Chong KL, Oli Mohamed S

Case Rep Ophthalmol Med, 2018;2018:8125806.
PMID: 30327738 DOI: 10.1155/2018/8125806

INTRODUCTION: To report an unusual case of CMV retinitis in Primary Immune Deficiency Disease (PIDD).
CASE REPORT: 13-year-old child with combined T and B cell deficiencies was diagnosed of bilateral zone 1 CMV retinitis. Intravitreal injections were unable to be given in a regular and timely manner under general anaesthesia due to her underlying systemic disease. The child was treated with intravenous ganciclovir for 8 weeks until eventual resolution of the retinitis. However, visual acuity deteriorated due to progressive optic nerve involvement.
CONCLUSION: Paediatric patients often do not notice subtle symptoms of CMV retinitis. Although ocular manifestations are uncommon in PIDD, recognition and high index of suspicion will allow for timely referral, diagnosis, and treatment to be instituted for better visual outcomes.
Fulltext The Pharmacological Potential of Oil Palm Phenolics (OPP) Individual Components

Syarifah-Noratiqah SB, Zulfarina MS, Ahmad SU, Fairus S, Naina-Mohamed I

Int J Med Sci, 2019;16(5):711-719.
PMID: 31217739 DOI: 10.7150/ijms.29934

The oil palm tree (Elaeis guineensis) from the family Arecaceae is a high oil-producing agricultural crop. A significant amount of vegetation liquor is discarded during the palm oil milling process amounting to 90 million tons per year around the world. This water-soluble extract is rich in phenolic compounds known as Oil Palm Phenolics (OPP). Several phenolic acids including the three isomers of caffeoylshikimic acid (CFA), p-hydroxybenzoic acid (PHBA), protocatechuic acid (PCA) and hydroxytyrosol are among the primary active ingredients in the OPP. Previous investigations have reported several positive pharmacological potentials by OPP such as neuroprotective and atheroprotective effects, anti-tumor and reduction in Aβ deposition in Alzheimer's disease model. In the current review, the pharmacological potential for CFA, PHBA, PCA and hydroxytyrosol is carefully reviewed and evaluated.
From farm to fork: identical clones and Tn6674-like elements in linezolid-resistant Enterococcus faecalis from food-producing animals and retail meat

Elghaieb H, Tedim AP, Abbassi MS, Novais C, Duarte B, Hassen A, et al.

J Antimicrob Chemother, 2020 01 01;75(1):30-35.
PMID: 31605129 DOI: 10.1093/jac/dkz419

OBJECTIVES: Increasing numbers of linezolid-resistant Enterococcus carrying optrA are being reported across different niches worldwide. We aimed to characterize the first optrA-carrying Enterococcus faecalis obtained from food-producing animals and retail meat samples in Tunisia.
METHODS: Seven optrA-carrying E. faecalis obtained from chicken faeces (n=3, August 2017) and retail chicken meat (n=4, August 2017) in Tunisia were analysed. Antimicrobial susceptibility was determined by disc diffusion, broth microdilution and Etest against 13 antibiotics, linezolid and tedizolid, respectively (EUCAST/CLSI). optrA stability (∼600 bacterial generations), transfer (filter mating) and location (S1-PFGE/hybridization) were characterized. WGS (Illumina-HiSeq) was done for four representatives that were analysed through in silico and genomic mapping tools.
RESULTS: Four MDR clones carrying different virulence genes were identified in chicken faeces (ST476) and retail meat (the same ST476 clone plus ST21 and ST859) samples. MICs of linezolid and tedizolid were stably maintained at 8 and 1-2 mg/L, respectively. optrA was located in the same transferable chromosomal Tn6674-like element in ST476 and ST21 clones, similar to isolates from pigs in Malaysia and humans in China. ST859 carried a non-conjugative plasmid of ∼40 kb with an impB-fexA-optrA segment, similar to plasmids from pigs and humans in China.
CONCLUSIONS: The same chromosomal and transferable Tn6674-like element was identified in different E. faecalis clones from humans and animals. The finding of retail meat contaminated with the same linezolid-resistant E. faecalis strain obtained from a food-producing animal highlights the potential role of the food chain in the worrisome dissemination of optrA that can be stably maintained without selective pressure over generations.
The Effects of Palm Oil on Plasma and Serum Lipid Parameters: A Systematic Review on Animal Intervention Studies

Syarifah-Noratiqah SB, Fairus S, Zulfarina MS, Nasrullah Z, Qodriyah HMS, Naina-Mohamed I

Front Vet Sci, 2020;7:303.
PMID: 32775343 DOI: 10.3389/fvets.2020.00303

Background: Accumulative evidences on the beneficial effects of palm oil are progressively reported; however, there are still several controversies related to their effects on the risks of cardiovascular disease (CVD). This review explores the effects of palm oil and its liquid fraction namely palm olein, which is commonly used as cooking oil on four lipid parameters; total cholesterol (TC), triglyceride (TG), high-density lipoprotein-cholesterol (HDL-C) and low-density lipoprotein-cholesterol (LDL-C), which play an important role as CVD-related biomarkers. A systematic review of the literature was conducted to identify the relevant studies on palm oil and the lipid parameters specifically focusing on the in-vivo animal model. Methods: A comprehensive search was conducted in Medline via EBSCOhost, Medline via OVID and Scopus. Studies were limited to the English language published between the years of 2000 and 2019. The main inclusion criteria were as follows: (1) Study with in-vivo animal experiments [the animal should be limited to mammals] (2) Study should have evaluated the effects of palm oil or palm olein on plasma or serum lipid parameter (3) Study should have used palm oil or palm olein in the form of pure or refined oil (4) The treatment of palm oil or palm olein was assessed using the following outcomes: plasma or serum TC, TG, HDL-C, and LDL-C concentration (5) Study should have control group and (6) studies on specific fatty acid, fraction enriched tocotrienol and tocopherol, crude palm oil, kernel oil, red palm oil, thermally oxidized palm oil, hydrogenated palm oil, and palm oil or palm olein based products namely margarine, palm milk, butter and cream were excluded. The quality and the risk of bias on the selected studies were assessed using the ARRIVE Guideline and SYRCLE's Risk of Bias tools, respectively. Results: The literature search successfully identified 17 potentially relevant articles, whereby nine of them met the inclusion criteria. All research articles included in this review were in vivo studies comprising seven rats, one hamster and one mice model. Conclusion: Significant positive outcomes were observed in several lipid parameters such as TC and LDL-C. The evidence from this review supported that palm oil and palm olein possess high potential as lipid-lowering agents.
Natural Polyphenols in the Treatment of Alzheimer's Disease

Syarifah-Noratiqah SB, Naina-Mohamed I, Zulfarina MS, Qodriyah HMS

Curr Drug Targets, 2018;19(8):927-937.
PMID: 28356027 DOI: 10.2174/1389450118666170328122527

Neurodegenerative disease is an incurable disease which involves the degeneration or death of the nerve cells. Alzheimer's Disease (AD) is a neurodegenerative disease discovered in 1906 by Alois Alzheimer, a German clinical psychiatrist and neuroanatomist. The main pathological hallmarks of this disease are the formation of extracellular amyloid β (Aβ) plaques and intracellular neurofibrillary tangle (NFT). The accumulation of the amyloid protein aggregates in the brain of AD patients leads to oxidative stress and inflammation. Other postulated reasons for the development of this disease are cholinergic depletion and excessive glutamatergic neurotransmission. The current drugs approved and marketed for the treatment of AD are cholinesterase inhibitors (ChEIs) and N-methyl-Daspartate (NMDA) receptor antagonists. The function of ChEIs is to avoid cholinergic depletion; whereas the function of NMDA receptor antagonist is to block excessive glutamatergic neurotransmission. Unfortunately, the current drugs prescribed for AD show only modest improvement in terms of symptomatic relief and delay the progression of the disease. This review will discuss about several polyphenolic compounds as potential natural treatment options for AD. Three compounds are highlighted in this review - Curcumin (Cur), Resveratrol (Rsv) and Epigallocatechin-3- gallate (EGCG). These compounds have huge potential for AD treatment, especially due to their low frequency of adverse events. However, the current conventional pharmaceutical drugs remain as the mainstay of treatment for AD.
Attention, Impulsiveness, and Gender in Academic Achievement Among Typically Developing Children

Alavi M, Seng JH, Mustaffa MS, Ninggal MT, Amini M, Latif AA

Percept Mot Skills, 2018 Nov 14.
PMID: 30426868 DOI: 10.1177/0031512518809163

Although several studies have examined the relationships among attention, impulse control, gender, and academic achievement, most have focused on clinical samples and have considered only one or two academic subjects. This study investigated these relationships among typically developing children using general achievement measures (academic scores and grades). Our participants were 270 typically developing primary school students (142 boys and 128 girls) of different nationalities living in Malaysia, recruited with purposive sampling with a mean age of 9.75 years. We found that both attention and impulse control significantly predicted academic achievement. Girls had a higher level of attention and impulse control than boys, but gender was not a significant moderator between either attention or impulse control and academic achievement. We discuss the implications of these findings and the need for further research.
Fulltext Pharmacological Therapy in Panic Disorder: Current Guidelines and Novel Drugs Discovery for Treatment-resistant Patient

Zulfarina MS, Syarifah-Noratiqah SB, Nazrun SA, Sharif R, Naina-Mohamed I

Clin Psychopharmacol Neurosci, 2019 May 31;17(2):145-154.
PMID: 30905115 DOI: 10.9758/cpn.2019.17.2.145

Panic disorder (PD) being one of the most intensively investigated anxiety disorders is considered a heterogeneous psychiatric disease which has difficulties with early diagnosis. The disorder is recurrent and usually associated with low remission rates and high rates of relapse which may exacerbated social and quality of life, causes unnecessary cost and increased risk for complication and suicide. Current pharmacotherapy for PD are available but these drugs have slow therapeutic onset, several side effects and most patients do not fully respond to these standard pharmacological treatments. Ongoing investigations indicate the need for new and promising agents for the treatment of PD. This article will cover the importance of immediate and proper treatment, the gap in the current management of PD with special emphasis on pharmacotherapy, and evidence regarding the novel anti-panic drugs including the drugs in developments such as metabotropic glutamate (mGlu 2/3) agonist and levetiracetam. Preliminary results suggest the anti-panic properties and the efficacy of duloxetine, reboxetine, mirtazapine, nefazodone, risperidone and inositol as a monotherapy drug. Apart for their effectiveness, the aforementioned compounds were generally well tolerated compared to the standard available pharmacotherapy drugs, indicating their potential therapeutic usefulness for ambivalent and hypervigilance patient. Further strong clinical trials will provide an ample support to these novel compounds as an alternative monotherapy for PD treatment-resistant patient.
Fulltext Polarization insensitive symmetrical structured double negative (DNG) metamaterial absorber for Ku-band sensing applications

Hakim ML, Alam T, Soliman MS, Sahar NM, Baharuddin MH, Almalki SHA, et al.

Sci Rep, 2022 Jan 10;12(1):479.
PMID: 35013437 DOI: 10.1038/s41598-021-04236-1

Metamaterial absorber (MMA) is now attracting significant interest due to its attractive applications, such as thermal detection, sound absorption, detection for explosive, military radar, wavelength detector, underwater sound absorption, and various sensor applications that are the vital part of the internet of things. This article proposes a modified square split ring resonator MMA for Ku-band sensing application, where the metamaterial structure is designed on FR-4 substrate material with a dielectric constant of 4.3 and loss tangent of 0.025. Perfect absorption is realized at 14.62 GHz and 16.30 GHz frequency bands, where peak absorption is about 99.99% for both frequency bands. The proposed structure shows 70% of the average absorption bandwidth of 420 MHz (14.42-14.84 GHz) and 480 MHz (16.06-16.54 GHz). The metamaterial property of the proposed structure is investigated for transverse electromagnetic mode (TEM) and achieved negative permittivity, permeability, and refractive index property for each absorption frequency band at 0°, 45°, and 90° polarization angles. Interference theory is also investigated to verify the absorption properties. Moreover, the permittivity sensor application is investigated to verify the sensor performance of the proposed structure. Finally, a comparison with recent works is performed, which shows that the proposed MMA can be a good candidate for Ku-band perfect absorber and sensing applications.
Fulltext Microwave brain imaging system to detect brain tumor using metamaterial loaded stacked antenna array

Hossain A, Islam MT, Beng GK, Kashem SBA, Soliman MS, Misran N, et al.

Sci Rep, 2022 Oct 01;12(1):16478.
PMID: 36183039 DOI: 10.1038/s41598-022-20944-8

In this paper, proposes a microwave brain imaging system to detect brain tumors using a metamaterial (MTM) loaded three-dimensional (3D) stacked wideband antenna array. The antenna is comprised of metamaterial-loaded with three substrate layers, including two air gaps. One 1 × 4 MTM array element is used in the top layer and middle layer, and one 3 × 2 MTM array element is used in the bottom layer. The MTM array elements in layers are utilized to enhance the performance concerning antenna's efficiency, bandwidth, realized gain, radiation directionality in free space and near the head model. The antenna is fabricated on cost-effective Rogers RT5880 and RO4350B substrate, and the optimized dimension of the antenna is 50 × 40 × 8.66 mm3. The measured results show that the antenna has a fractional bandwidth of 79.20% (1.37-3.16 GHz), 93% radiation efficiency, 98% high fidelity factor, 6.67 dBi gain, and adequate field penetration in the head tissue with a maximum of 0.0018 W/kg specific absorption rate. In addition, a 3D realistic tissue-mimicking head phantom is fabricated and measured to verify the performance of the antenna. Later, a nine-antenna array-based microwave brain imaging (MBI) system is implemented and investigated by using phantom model. After that, the scattering parameters are collected, analyzed, and then processed by the Iteratively Corrected delay-multiply-and-sum algorithm to detect and reconstruct the brain tumor images. The imaging results demonstrated that the implemented MBI system can successfully detect the target benign and malignant tumors with their locations inside the brain.
Phytoremediation of bauxite wastewater potentiality by Jatropa curcas

Kristanti RA, Mardarveran P, Almaary KS, Elshikh MS, AbdelGawwad MR, Tang DKH

Bioprocess Biosyst Eng, 2023 Mar;46(3):373-379.
PMID: 35773493 DOI: 10.1007/s00449-022-02745-5

Bauxite wastewater creates soil contamination and produces toxic effects on human health such as respiratory and skin rash problems. In this study, we investigated the phytoremediation ability of Jatropha curcas to remove bauxite wastewater from soil. Pot experiments were conducted to investigate the bauxite wastewater on the phytoremediation potential of J. curcas grown in contaminated soils. J. curcas exhibited a significant increase in plant growth leaf, root activity, plant height, and plant shoot when grown in bauxite contaminated soils compared with J. curcas grown in uncontaminated soils after 30 d treatment. Under bauxite exposure, a higher aluminium removal (88.5%) was observed in soils planted with J. curcas than unplanted soils (39.6%). The bioconcentration factor was also found to be 5.62, indicating that J. curcas have great tolerance and hyperaccumulator of aluminium under high aluminium concentrations and are capable of phytoextraction of soil contaminated with bauxite wastewater.
Fulltext Metamaterial based on an inverse double V loaded complementary square split ring resonator for radar and Wi-Fi applications

Islam MR, Islam MT, Soliman MS, Baharuddin MH, Mat K, Moubark AM, et al.

Sci Rep, 2021 Nov 05;11(1):21782.
PMID: 34741089 DOI: 10.1038/s41598-021-01275-6

In this research paper, an inverse double V loaded complementary square split ring resonator based double negative (DNG) metamaterial has been developed and examined numerically and experimentally. The electromagnetic (EM) properties of the proposed inverse double V-structure were calculated using computer simulation technology (CST-2019) and the finite integration technique (FIT). The designed metamaterial provides three resonance frequencies are 2.86, 5, and 8.30 GHz, covering S-, C-, and X-bands. The total size of the recommended unit cell is 8 [Formula: see text] 8 [Formula: see text] 1.524 mm3, and a high effective medium ratio (EMR) value of 13.11 was found from it. The - 10 dB bandwidths of this structure are 2.80 to 2.91, 4.76 to 5.17, and 8.05 to 8.42 GHz. The proposed structure's novelty is its small size, simple resonator structure, which provides double negative characteristics, high EMR, maximum coverage band, and required resonance frequencies. Wi-Fi network speeds are generally faster when frequencies in the 5 GHz band are used. Since the proposed structure provides a 5 GHz frequency band, hence the suggested metamaterial can be used in Wi-Fi for high bandwidth and high-speed applications. The marine radars operate in X-band, and weather radar works in S-band. Since the designed cell provides two more resonance frequencies, i.e., 2.86 GHz (S-band) and 8.30 GHz (X-band), the proposed metamaterial could be used in weather radar and marine radar. The design process and various parametric studies have been analyzed in this article. The equivalent circuit is authenticated using the advanced design system (ADS) software compared with CST simulated result. The surface current, E-field, and H-field distributions have also been analyzed. Different types of array structure, i.e., 1 [Formula: see text] 2, 2 [Formula: see text] 2, 3 [Formula: see text] 3, 4 [Formula: see text] 4, and 20 [Formula: see text] 25 is examined and validated by the measured result. The simulated and measured outcome is an excellent agreement for the inverse double V loaded CSSRR unit cell and array. We showed the overall performance of the suggested structure is better than the other structures mentioned in the paper. Since the recommended metamaterial unit cell size is small, provides desired resonance frequency, gives a large frequency band and high EMR value; hence the suggested metamaterial can be highly applicable for Radar and Wi-Fi.
Fulltext Machine learning assisted hepta band THz metamaterial absorber for biomedical applications

Jain P, Chhabra H, Chauhan U, Prakash K, Gupta A, Soliman MS, et al.

Sci Rep, 2023 Jan 31;13(1):1792.
PMID: 36720922 DOI: 10.1038/s41598-023-29024-x

A hepta-band terahertz metamaterial absorber (MMA) with modified dual T-shaped resonators deposited on polyimide is presented for sensing applications. The proposed polarization sensitive MMA is ultra-thin (0.061 λ) and compact (0.21 λ) at its lowest operational frequency, with multiple absorption peaks at 1.89, 4.15, 5.32, 5.84, 7.04, 8.02, and 8.13 THz. The impedance matching theory and electric field distribution are investigated to understand the physical mechanism of hepta-band absorption. The sensing functionality is evaluated using a surrounding medium with a refractive index between 1 and 1.1, resulting in good Quality factor (Q) value of 117. The proposed sensor has the highest sensitivity of 4.72 THz/RIU for glucose detection. Extreme randomized tree (ERT) model is utilized to predict absorptivities for intermediate frequencies with unit cell dimensions, substrate thickness, angle variation, and refractive index values to reduce simulation time. The effectiveness of the ERT model in predicting absorption values is evaluated using the Adjusted R2 score, which is close to 1.0 for nmin = 2, demonstrating the prediction efficiency in various test cases. The experimental results show that 60% of simulation time and resources can be saved by simulating absorber design using the ERT model. The proposed MMA sensor with an ERT model has potential applications in biomedical fields such as bacterial infections, malaria, and other diseases.
Fulltext Quality of energy intake in Malaysian adolescents: prevalence, characteristics, determinants and impact of implausible reporters

Zulfarina MS, Sharif R, Sharkawi AM, Mokhtar SA, Shuid AN, Naina-Mohamed I

Public Health Nutr, 2023 Jan;26(1):122-131.
PMID: 35321764 DOI: 10.1017/S1368980022000726

OBJECTIVE: Misreporting of energy intake (EI) in nutritional epidemiology is common and even severe among adolescents. Thus, the current study aims to examine the presence, bias and impact introduced by implausible reporters.
DESIGN: Cross-sectional.
SETTING: Central and eastern regions of Peninsular Malaysia.
PARTICIPANTS: A stratified random sampling was employed to select 917 secondary school-going adolescents (aged 15-17 years).
RESULTS: The prevalence of under-reporters was 17·4 %, while no over-reporters were identified. Under-reporters had higher body composition and lower dietary intakes (except for vitamin C, Cr and Fl) compared with plausible reporters (P < 0·05). Adolescents with overweight and obesity had a higher odds of under-reporting compared with under-/normal weight adolescents (P < 0·001). In model 3, the highest regression coefficient (R2 = 0·404, P < 0·001) was obtained after adjusting for reporting status.
CONCLUSIONS: Overweight and obese adolescents were more likely to under-report their food intake and consequently affect nutrient intakes estimates. Future analyses that include nutrient intake data should adjust for reporting status so that the impact of misreporting on study outcomes can be conceded and consequently improve the accuracy of dietary-related results.
Experimental study and theoretical prediction of mechanical properties of ultra-high-performance concrete incorporated with nanorice husk ash burning at different temperature treatments

Mostafa SA, Ahmed N, Almeshal I, Tayeh BA, Elgamal MS

Environ Sci Pollut Res Int, 2022 Oct;29(50):75380-75401.
PMID: 35655017 DOI: 10.1007/s11356-022-20779-w

This research aimed to investigate the effect of nanorice husk ash (NRHA) prepared using different thermal treatment methods on ultra-high-performance concrete (UHPC) behaviour. NRHA was prepared by two methods: (1) burning for 3 h at 300, 500, 700 and 900 °C and (2) burning for different durations (9, 7, 5 and 3 h) at 300, 500, 700 and 900 °C. NRHA was added to UHPC to make 25 mixtures with three dosages (1%, 3% and 5%). Density, compressive strength, tensile strength, flexure strength and ultrasonic pulse velocity tests were performed at the experimental level. Moreover, full microstructure analysis, including X-ray diffractometry, Brunauer-Emmett-Teller surface area analysis, thermogravimetric analysis, scanning electron microscopy and energy-dispersive X-ray spectroscopy, was performed. The best performances in in the first method (constant duration, different temperatures) were obtained by 1% NRHA burned at 900 °C with 12.5% compressive strength and 1% NRHA burned at 700 °C with increased ratio (10%). Moreover, the best performance in the second method (different burning durations and temperatures) was obtained by 3% NRHA with a ratio of 22.5% at 700 °C for 5 h. Burning rice husk ash improved the compressive strength. It also remarkably improved the splitting tensile strength and flexure strength by 32% and 47%, respectively, at 3% NRHA treated at 700 °C for 3 h. The microstructural analysis showed the efficient role of NRHA in the compactness of concrete sections. It improved the formation of new calcium silicate hydrate gel; decreased the cracks, voids, CaCO3 and Ca(OH)2; and increased the Ca/Si composition. The obtained experimental results were used to build an artificial neural network (ANN) to predict UHPC properties. The ANN model was used as a validation tool to determine the correlation between results. Results showed a remarkable improvement in the mechanical properties of UHPC incorporating NRHA for all mixtures. The ANN model indicated a reliable correlation between input and output variables. The R2 values for the training, validation and testing steps were all 0.99.
Fulltext Double-negative metamaterial square enclosed Q.S.S.R For microwave sensing application in S-band with high sensitivity and Q-factor

Khalil MA, Yong WH, Islam MT, Hoque A, Islam MS, Leei CC, et al.

Sci Rep, 2023 May 05;13(1):7373.
PMID: 37147337 DOI: 10.1038/s41598-023-34514-z

Metamaterials have gained much attention due to their exciting characteristics and potential uses in constructing valuable technologies. This paper presents a double negative square resonator shape metamaterial sensor to detect the material and its thickness. An innovative double-negative metamaterial sensor for microwave sensing applications is described in this paper. It has a highly sensitive Q-factor and has good absorption characteristics approximately equal to one. For the metamaterial sensor, the recommended measurement is 20 by 20 mm. Computer simulation technology (C.S.T.) microwave studios are used to design the metamaterial structure and figure out its reflection coefficient. Various parametric analyses have been performed to optimize the design and size of the structure. The experimental and theoretical results are shown for a metamaterial sensor that is attached to five different materials such as, Polyimide, Rogers RO3010, Rogers RO4350, Rogers RT5880, and FR-4. A sensor's performance is evaluated using three different thicknesses of FR-4. There is a remarkable similarity between the measured and simulated outcomes. The sensitivity values for 2.88 GHz and 3.5 GHz are 0.66% and 0.19%, respectively, the absorption values for both frequencies are 99.9% and 98.9%, respectively, and the q-factor values are 1413.29 and 1140.16, respectively. In addition, the figure of merit (FOM) is analyzed, and its value is 934.18. Furthermore, the proposed structure has been tested against absorption sensor applications for the purpose of verifying the sensor's performance. With a high sense of sensitivity, absorption, and Q-factor, the recommended sensor can distinguish between thicknesses and materials in various applications.
Fulltext Author Correction: Double-negative metamaterial square enclosed Q.S.S.R For microwave sensing application in S-band with high sensitivity and Q-factor

Khalil MA, Yong WH, Islam MT, Hoque A, Islam MS, Leei CC, et al.

Sci Rep, 2023 May 22;13(1):8248.
PMID: 37217777 DOI: 10.1038/s41598-023-35422-y

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