Displaying publications 21 - 40 of 392 in total

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  1. Usman A, Chantrapromma S, Fun HK
    Acta Crystallogr C, 2001 Dec;57(Pt 12):1443-6.
    PMID: 11740112
    The title compound, 3,5,7-triaza-1-azoniatricyclo[3.3.1.1(3,7)]decane 2,4-dinitrophenolate monohydrate, C6H13N4+*C6H3N2O5-*H2O, the 1:1 hydrate adduct of hexamethylenetetramine (HMT) and 2,4-dinitrophenol, undergoes a temperature phase transition. In the room-temperature phase, the adduct crystallizes in the monoclinic P2(1)/m space group, whereas in the low-temperature phase, the adduct crystallizes in the triclinic P1 space group. This phase transition is reversible, with the transition temperature at 273 K, and the phase transition is governed by hydrogen bonds and weak interactions. In both these temperature-dependent polymorphs, the crystal structure is alternately layered with sheets of hexamethylenetetramine and sheets of dinitrophenol stacked along the c axis. The hexamethylenetetramine and dinitrophenol moieties are linked by intermolecular hydrogen bonds. The water molecule in the adduct plays an important role, forming O-H...O hydrogen bonds which, together with C-H...O hydrogen bonds, bridge the adducts into molecular ribbons. Extra hydrogen bonds and weak interactions exist for the low-temperature polymorph and these interconnect the molecular ribbons into a three-dimensional packing structure. Also in these two temperature-dependent polymorphs, dinitrophenol acts as a hydrogen-bond acceptor and HMT acts as a hydrogen-bond donor.
  2. Tariq MU, Ismail SB
    Osong Public Health Res Perspect, 2024 Apr;15(2):115-136.
    PMID: 38621765 DOI: 10.24171/j.phrp.2023.0287
    BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic continues to pose significant challenges to the public health sector, including that of the United Arab Emirates (UAE). The objective of this study was to assess the efficiency and accuracy of various deep-learning models in forecasting COVID-19 cases within the UAE, thereby aiding the nation's public health authorities in informed decision-making.

    METHODS: This study utilized a comprehensive dataset encompassing confirmed COVID-19 cases, demographic statistics, and socioeconomic indicators. Several advanced deep learning models, including long short-term memory (LSTM), bidirectional LSTM, convolutional neural network (CNN), CNN-LSTM, multilayer perceptron, and recurrent neural network (RNN) models, were trained and evaluated. Bayesian optimization was also implemented to fine-tune these models.

    RESULTS: The evaluation framework revealed that each model exhibited different levels of predictive accuracy and precision. Specifically, the RNN model outperformed the other architectures even without optimization. Comprehensive predictive and perspective analytics were conducted to scrutinize the COVID-19 dataset.

    CONCLUSION: This study transcends academic boundaries by offering critical insights that enable public health authorities in the UAE to deploy targeted data-driven interventions. The RNN model, which was identified as the most reliable and accurate for this specific context, can significantly influence public health decisions. Moreover, the broader implications of this research validate the capability of deep learning techniques in handling complex datasets, thus offering the transformative potential for predictive accuracy in the public health and healthcare sectors.

  3. Tariq MU, Ismail SB
    PLoS One, 2024;19(3):e0294289.
    PMID: 38483948 DOI: 10.1371/journal.pone.0294289
    The COVID-19 pandemic has had a significant impact on both the United Arab Emirates (UAE) and Malaysia, emphasizing the importance of developing accurate and reliable forecasting mechanisms to guide public health responses and policies. In this study, we compared several cutting-edge deep learning models, including Long Short-Term Memory (LSTM), bidirectional LSTM, Convolutional Neural Networks (CNN), hybrid CNN-LSTM, Multilayer Perceptron's, and Recurrent Neural Networks (RNN), to project COVID-19 cases in the aforementioned regions. These models were calibrated and evaluated using a comprehensive dataset that includes confirmed case counts, demographic data, and relevant socioeconomic factors. To enhance the performance of these models, Bayesian optimization techniques were employed. Subsequently, the models were re-evaluated to compare their effectiveness. Analytic approaches, both predictive and retrospective in nature, were used to interpret the data. Our primary objective was to determine the most effective model for predicting COVID-19 cases in the United Arab Emirates (UAE) and Malaysia. The findings indicate that the selected deep learning algorithms were proficient in forecasting COVID-19 cases, although their efficacy varied across different models. After a thorough evaluation, the model architectures most suitable for the specific conditions in the UAE and Malaysia were identified. Our study contributes significantly to the ongoing efforts to combat the COVID-19 pandemic, providing crucial insights into the application of sophisticated deep learning algorithms for the precise and timely forecasting of COVID-19 cases. These insights hold substantial value for shaping public health strategies, enabling authorities to develop targeted and evidence-based interventions to manage the virus spread and its impact on the populations of the UAE and Malaysia. The study confirms the usefulness of deep learning methodologies in efficiently processing complex datasets and generating reliable projections, a skill of great importance in healthcare and professional settings.
  4. Shafiullah M, Khalid U, Shahbaz M
    Environ Sci Pollut Res Int, 2021 Mar;28(9):11415-11429.
    PMID: 33118073 DOI: 10.1007/s11356-020-11331-9
    This study empirically investigates the effect of meat consumption on greenhouse gas emissions (carbon dioxide, methane, and nitrous oxide) in the USA. The impact of meat consumption on greenhouse gas emissions is examined by controlling for economic growth and energy consumption. The empirical analysis finds that all these variables are cointegrated for the long run. Moreover, meat consumption aggravates greenhouse gas emissions. Specifically, meat consumption (except for beef) has a U-shaped relationship with carbon emissions and an inverted U-shaped relationship with methane and nitrous oxide emissions. The causality analysis indicates a unidirectional causality running from meat consumption to greenhouse gas emissions. These empirical findings indicate that the US livestock sector has the potential to become more environmentally friendly with careful policy formulation and implementation.
  5. Abubakar U, Sulaiman SAS
    J Infect Public Health, 2018;11(6):763-770.
    PMID: 29933910 DOI: 10.1016/j.jiph.2018.05.013
    BACKGROUND: Evidence to demonstrate the prevalence and trend of Methicillin Resistant Staphylococcus aureus (MRSA) infection in Nigeria is scarce. This review evaluates the prevalence, trend and antimicrobial susceptibility of clinical MRSA isolates reported in published studies.

    METHOD: Electronic search (PubMed, Scopus and Google scholar) was conducted using the following search terms: "MRSA OR Methicillin Resistant Staphylococcus aureus AND Nigeria." Reference list of selected studies was scanned to identify more studies. Studies published between 2007 and 2017 that tested at least 30 non-duplicate S. aureus isolates were selected. An independent reviewer extracted data from the studies using a standardized form.

    RESULTS: Twelve studies were included in this review. Overall, prevalence of MRSA infection increased from 18.3% (2009) to 42.3% (2013). The prevalence of MRSA infection was less than 50% in all the regions during the period under review. There was a decline in the prevalence of MRSA infection in the North-East (from 12.5% to 8.0%) between 2007 and 2012, and an increase in the South-West (from 20.2% to 47.4%) between 2006 and 2010. Wound, blood and urine specimens had the highest proportion of MRSA isolates. Non-susceptibility of MRSA strains to cotrimoxazole and tetracycline was greater than 85%.

    CONCLUSION: Prevalence of MRSA infection in Nigeria is rising, albeit regional variations. Non-susceptibility to commonly prescribed, orally available and inexpensive antibiotics was high. Antimicrobial resistance surveillance system, infection control, and antimicrobial stewardship interventions are recommended.

  6. Ji X, Usman A, Razalli NH, Sambanthamurthi R, Gupta SV
    Anticancer Res, 2015 Jan;35(1):97-106.
    PMID: 25550539
    Oil palm phenolics (OPP) or Palm Juice (PJ), a water soluble extract from the palm fruit (Elaies guineensis) has been documented to have anti-carcinogenic activities in various cancer types.
  7. Usman J, McIntosh AS, Quarrie K, Targett S
    J Sci Med Sport, 2015 Sep;18(5):529-33.
    PMID: 25156881 DOI: 10.1016/j.jsams.2014.07.020
    Shoulder injuries in rugby union football have been the focus of few in-depth studies, despite their frequency and severity. The study's objective was to describe the incidence, patterns and mechanisms of shoulder injuries in rugby.
  8. Das NS, Usman J, Choudhury D, Abu Osman NA
    PLoS One, 2014;9(6):e100028.
    PMID: 24927127 DOI: 10.1371/journal.pone.0100028
    Cricket has over the years gained much popularity in Asia, thus the number of cricket players has also grown in tandem. However, cricket players are not as fortunate as other athletes as they do not always have a standard cricket infrastructure to practice; therefore, the injury prevalence is expected to be high. Unfortunately, very few studies have been conducted to investigate the nature and pattern of cricket injuries prevalent to cricketers in this region. Therefore, a prospective cohort injury surveillance study was conducted during the Asian Cricket Council (ACC) Under-19 Elite Cup held in June 2013 in order to gather more data on the type of injuries sustained by cricket players. Overall, 31 injuries occurred to 28 players throughout the tournament, of which 7 injuries happened during practice sessions. The overall injury incidence rate (IIR) was 292.0 per 10,000 player hours (95% CI 176.9-407.1) and 10.4 per 10,000 balls faced and 2.6 per 1000 overs bowled delivered during batting and bowling, respectively. Injuries to the lower limb (IIR: 146; 95% CI 1.8-98.2) were the most frequent, followed by injuries to the upper limb (97.3;95% CI 30.2-164.5) and to the trunk and back (IIR: 36.5;95% CI 0.0-77.7). Sprain/strains (IIR 109.5;95% CI 38.4-180.7) to muscle/tendon and joint/ligament were the most commonly reported nature of injury. This is the first study investigating injury incidence among the players of the ACC. It provides an overview of injuries sustained by elite players' under-19 years of age from 10 Asian countries. The overall IIR is similar to earlier studies conducted in well-established cricket playing nations.
  9. Usman AS, Mustaffa R, Ramli N, Diggi SA
    Asian J Transfus Sci, 2013 Jan;7(1):84-5.
    PMID: 23559775 DOI: 10.4103/0973-6247.106750
    OBJECTIVE: Maternal allo-antibody production is stimulated when fetal red blood cells are positive for an antigen absent on the mother's red cells. The maternal IgG antibodies produced will pass through the placenta and attack fetal red cells carrying the corresponding antigen. Allo-immune hemolytic disease of the fetus and newborn caused by anti-E rarely occurs.

    CASE SUMMARY: We report two cases of anti-E hemolytic diseases in neonates. One of the neonates had severe hemolysis presenting with severe anemia, thrombocytopenia, and conjugated hyperbilirubinemia, while the other had moderate anemia and unconjugated hyperbilrubinemia. Although both the neonates were treated by phototherapy and intravenous immunoglobulin, one of them received double volume exchange transfusion.

    CONCLUSION: There appeared to be an increase in the occurrence of hemolytic disease of the fetus and newborn caused by Rh antibodies other than anti-D. In this case report, both patients presented with anemia and hyperbilirubinemia but were successfully treated, with a favorable outcome.

  10. Bello I, Usman NS, Mahmud R, Asmawi MZ
    J Ethnopharmacol, 2015 Dec 4;175:422-31.
    PMID: 26429073 DOI: 10.1016/j.jep.2015.09.031
    Alstonia scholaris has a long history of use in the Ayurveda traditional treatment of various ailments including hypertension. We have reported the blood pressure lowering activity of the extract of A. scholaris. The following research aim to delineate the pharmacological mechanism involve in the antihypertensive action.
  11. Usman MG, Rafii MY, Martini MY, Oladosu Y, Kashiani P
    J Sci Food Agric, 2017 Mar;97(4):1164-1171.
    PMID: 27290898 DOI: 10.1002/jsfa.7843
    BACKGROUND: Studies on genotypic and phenotypic correlations among characters of crop plants are useful in planning, evaluating and setting selection criteria for the desired characters in a breeding program. The present study aimed to estimate the phenotypic correlation coefficients among yield and yield attributed characters and to work out the direct and indirect effects of yield-related characters on yield per plant using path coefficient analysis. Twenty-six genotypes of chili pepper were laid out in a randomized complete block design with three replications.

    RESULTS: Yield per plant showed positive and highly significant (P ≤ 0.01) correlations with most of the characters studied at both the phenotypic and genotypic levels. By contrast, disease incidence and days to flowering showed a significant negative association with yield. Fruit weight and number of fruits exerted positive direct effect on yield and also had a positive and significant (P ≤ 0.01) correlation with yield per plant. However, fruit length showed a low negative direct effect with a strong and positive indirect effect through fruit weight on yield and had a positive and significant association with yield.

    CONCLUSION: Longer fruits, heavy fruits and a high number of fruits are variables that are related to higher yields of chili pepper under tropical conditions and hence could be used as a reliable indicator in indirect selection for yield. © 2016 Society of Chemical Industry.

  12. Usman A, Chantrapromma S, Fun HK, Poh BL, Karalai C
    Acta Crystallogr C, 2002 Mar;58(Pt 3):o136-8.
    PMID: 11870305
    In the title 1/2/2 adduct, C(4)H(12)N(2)(2+) x 2C(6)H(3)N(2)O(5)(-) x 2H(2)O, the dication lies on a crystallographic inversion centre and the asymmetric unit also has one anion and one water molecule in general positions. The 2,4-dinitrophenolate anions and the water molecules are linked by two O-H...O and two C-H...O hydrogen bonds to form molecular ribbons, which extend along the b direction. The piperazine dication acts as a donor for bifurcated N-H...O hydrogen bonds with the phenolate O atom and with the O atom of the o-nitro group. Six symmetry-related molecular ribbons are linked to a piperazine dication by N---H.O and C---H.O hydrogen bonds.
  13. Chantrapromma S, Usman A, Fun HK, Poh BL, Karalai C
    Acta Crystallogr C, 2002 Sep;58(Pt 9):o589-90.
    PMID: 12205398
    In the title ternary complex, C(10)H(9)N(2)(+).C(7)H(3)N(2)O(6)(-).C(7)H(4)N(2)O(6), the pyridinium cation adopts the role of the donor in an intermolecular N-H.O hydrogen-bonding interaction with the carboxylate group of the 3,5-dinitrobenzoate anion. The molecules of the ternary complex form molecular ribbons perpendicular to the b direction, which are stabilized by one N-H.O, one O-H.O and five C-H.O intermolecular hydrogen bonds. The ribbons are further interconnected by three intermolecular C-H.O hydrogen bonds into a three-dimensional network.
  14. Chantrapromma S, Usman A, Fun HK, Poh BL, Karalai C
    Acta Crystallogr C, 2002 Nov;58(Pt 11):o675-7.
    PMID: 12415179
    In the title adduct, 1,3,5,7-tetraazatricyclo[3.3.1.1(3,7)]decane-4-nitrobenzene-1,2-diol-water (1/2/1), C(6)H(12)N(4).2C(6)H(5)NO(4).H(2)O, the hexamethylenetetramine molecule acts as an acceptor of intermolecular O-H.N hydrogen-bonding interactions from the water molecule and the hydroxy groups of one of the two symmetry-independent 4-nitrocatechol molecules. The structure is built from molecular layers which are stabilized by three intermolecular O-H.O, two intermolecular O-H.N and four intermolecular C-H.O hydrogen bonds. The layers are further interconnected by one additional intermolecular O-H.N and two intermolecular C-H.O hydrogen bonds.
  15. Rahman AA, Usman A, Chantrapromma S, Fun HK
    Acta Crystallogr C, 2003 Sep;59(Pt 9):i92-4.
    PMID: 12944636
    A sample of hydronium perchlorate, H(3)O(+) x ClO(4)(-), crystallized from ethanol at ambient temperature, was found to be orthorhombic (space group Pnma) at both 193 and 293 K, with no phase transition observed in this temperature range. This contrasts with the earlier observation [Nordman (1962). Acta Cryst. 15, 18-23] of a monoclinic phase (space group P2(1)/n) at 193 K for crystals grown at that temperature from perchloric acid. The hydronium and perchlorate ions lie across a mirror plane but it is not possible to define at either temperature a simple description of the H-atom positions due to the three-dimensional tumbling of the hydronium cation.
  16. Usman A, Chantrapromma S, Fun HK, Poh BL, Karalai C
    Acta Crystallogr C, 2002 Jan;58(Pt 1):o48-50.
    PMID: 11781494
    In the title complex, C6H12N4*C8H8O3, the hexamethylenetetramine molecule accepts a single intermolecular O-H...N hydrogen bond from the hydroxy group of the 4-hydroxy-3-methoxybenzaldehyde moiety. The non-centrosymmetric crystal structure is built from alternating molecular sheets of 4-hydroxy-3-methoxybenzaldehyde and hexamethylenetetramine molecules, and is stabilized by intermolecular O-H...N, C-H...O and C-H...pi interactions.
  17. Usman A, Chantrapromma S, Fun HK, Poh BL, Karalai C
    Acta Crystallogr C, 2002 Jan;58(Pt 1):o46-7.
    PMID: 11781493
    In the title complex, the 1:1 ionic adduct of hexamethylenetetraminium and 2,4,6-trinitrophenolate, C6H13N4+*C6H2N3O7-, the cation acts as a donor for bifurcated hydrogen bonds to the O atoms of the phenolate and one of the nitro groups of the 2,4,6-trinitrophenolate anion. The crystal structure is built from sheets of cations and anions, and is stabilized by intermolecular C-H...O and C-H...pi interactions.
  18. Usman A, Fun HK, Wang L, Zhang Y, Xu JH
    Acta Crystallogr C, 2003 Jun;59(Pt 6):o305-7.
    PMID: 12794346
    In the title compounds, C(21)H(18)N(2)O(4) and C(25)H(18)N(2)O(4), respectively, the five-membered ring of the indole system is almost planar. The oxetane and oxazole rings are individually planar. The orientations of the indole, oxetane, oxazole and phenyl moieties are conditioned by the sp(3) nature of the spiro-C atoms. In both compounds, the relative orientation of the indole and oxazole rings is opposite.
  19. Usman A, Fun HK, Li Y, Xu JH
    Acta Crystallogr C, 2003 Jun;59(Pt 6):o308-10.
    PMID: 12794347
    9,10-Diphenyl-9,10-epidioxyanthracene, C(26)H(18)O(2), (I), was accidentally used in a photooxygenation reaction that produced 9,10-dihydro-10,10-dimethoxy-9-phenylanthracen-9-ol, C(22)H(20)O(3), (II). In both compounds, the phenyl rings are approximately orthogonal to the anthracene moiety. The conformation of the anthracene moiety differs as a result of substitution. Intramolecular C-H.O interactions in (I) form two approximately planar S(5) rings in each of the two crystallographically independent molecules. The packing of (I) and (II) consists of molecular dimers stabilized by C-H.O interactions and of molecular chains stabilized by O-H.O interactions, respectively.
  20. Fun HK, Kannan S, Usman A, Abdul-Razak I, Chantrapromma S
    Acta Crystallogr C, 2002 Jul;58(Pt 7):m368-70.
    PMID: 12094029
    In the title compound, [UO(2)(C(15)H(11)O(2))(2)(C(14)H(14)OS)], the U(VI) atom is coordinated by seven O atoms in a distorted pentagonal-bipyramidal geometry. Both diphenylpropane-1,3-dionate systems are nearly planar. The sulfoxide moiety is in a distorted tetrahedral geometry, while its two aromatic rings are nearly orthogonal to one another. The crystal packing is stabilized by two bifurcated hydrogen-bonding interactions involving both uranyl O atoms.
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