Browse publications by year: 2020

  1. Cho J, Kandane-Rathnayake R, Louthrenoo W, Hoi A, Golder V, Chen YH, et al.
    Int J Rheum Dis, 2020 Aug;23(9):1255-1257.
    PMID: 32841510 DOI: 10.1111/1756-185X.13937
    MeSH terms: Adult; Asia/epidemiology; Australia/epidemiology; Female; Health Surveys; Humans; Immunosuppressive Agents/therapeutic use; Lupus Erythematosus, Systemic/drug therapy; Lupus Erythematosus, Systemic/immunology; Lupus Erythematosus, Systemic/epidemiology*; Middle Aged; New Zealand/epidemiology; Opportunistic Infections/immunology; Opportunistic Infections/epidemiology*; Opportunistic Infections/therapy; Immunocompromised Host; Treatment Outcome
  2. Peng W, Ma NL, Zhang D, Zhou Q, Yue X, Khoo SC, et al.
    Environ Res, 2020 12;191:110046.
    PMID: 32841638 DOI: 10.1016/j.envres.2020.110046
    Locusts differ from ordinary grasshoppers in their ability to swarm over long distances and are among the oldest migratory pests. The ecology and biology of locusts make them among the most devastating pests worldwide and hence the calls for actions to prevent the next outbreaks. The most destructive of all locust species is the desert locust (Schistocerca gregaria). Here, we review the current locust epidemic 2020 outbreak and its causes and prevention including the green technologies that may provide a reference for future directions of locust control and food security. Massive locust outbreaks threaten the terrestrial environments and crop production in around 100 countries of which Ethiopia, Somalia and Kenya are the most affected. Six large locust outbreaks are reported for the period from 1912 to 1989 all being closely related to long-term droughts and warm winters coupled with occurrence of high precipitation in spring and summer. The outbreaks in East Africa, India and Pakistan are the most pronounced with locusts migrating more than 150 km/day during which the locusts consume food equivalent to their own body weight on a daily basis. The plague heavily affects the agricultural sectors, which is the foundation of national economies and social stability. Global warming is likely the main cause of locust plague outbreak in recent decades driving egg spawning of up to 2-400,000 eggs per square meter. Biological control techniques such as microorganisms, insects and birds help to reduce the outbreaks while reducing ecosystem and agricultural impacts. In addition, green technologies such as light and sound stimulation seem to work, however, these are challenging and need further technological development incorporating remote sensing and modelling before they are applicable on large-scales. According to the Food and Agriculture Organization (FAO) of the United Nations, the 2020 locust outbreak is the worst in 70 years probably triggered by climate change, hurricanes and heavy rain and has affected a total of 70,000 ha in Somalia and Ethiopia. There is a need for shifting towards soybean, rape, and watermelon which seems to help to prevent locust outbreaks and obtain food security. Furthermore, locusts have a very high protein content and is an excellent protein source for meat production and as an alternative human protein source, which should be used to mitigate food security. In addition, forestation of arable land improves local climate conditions towards less precipitation and lower temperatures while simultaneously attracting a larger number of birds thereby increasing the locust predation rates.
    MeSH terms: Animals; Disease Outbreaks; Grasshoppers*; Humans; India; Kenya; Pakistan; Ecosystem; Global Warming
  3. Basri RS, Rahman RNZRA, Kamarudin NHA, Ali MSM
    Int J Biol Macromol, 2020 Dec 01;164:3155-3162.
    PMID: 32841666 DOI: 10.1016/j.ijbiomac.2020.08.162
    The conversion of aldehydes to valuable alkanes via cyanobacterial aldehyde deformylating oxygenase is of great interest. The availability of fossil reserves that keep on decreasing due to human exploitation is worrying, and even more troubling is the combustion emission from the fuel, which contributes to the environmental crisis and health issues. Hence, it is crucial to use a renewable and eco-friendly alternative that yields compound with the closest features as conventional petroleum-based fuel, and that can be used in biofuels production. Cyanobacterial aldehyde deformylating oxygenase (ADO) is a metal-dependent enzyme with an α-helical structure that contains di‑iron at the active site. The substrate enters the active site of every ADO through a hydrophobic channel. This enzyme exhibits catalytic activity toward converting Cn aldehyde to Cn-1 alkane and formate as a co-product. These cyanobacterial enzymes are small and easy to manipulate. Currently, ADOs are broadly studied and engineered for improving their enzymatic activity and substrate specificity for better alkane production. This review provides a summary of recent progress in the study of the structure and function of ADO, structural-based engineering of the enzyme, and highlight its potential in producing biofuels.
    MeSH terms: Cyanobacteria/enzymology*; Bacterial Proteins/metabolism; Bacterial Proteins/chemistry; Catalysis; Enzymes, Immobilized/metabolism; Enzymes, Immobilized/chemistry; Hot Temperature; Mixed Function Oxygenases/metabolism*; Mixed Function Oxygenases/chemistry*; Silicon Dioxide/chemistry*; Substrate Specificity; 3,4-Dihydroxyphenylacetic Acid/metabolism; Catalytic Domain; Biofuels/analysis; Magnetite Nanoparticles
  4. Samoh N, Peerawaranun P, Jonas KJ, Lim SH, Wickersham JA, Guadamuz TE
    Sex Transm Dis, 2020 Aug 24.
    PMID: 32842048 DOI: 10.1097/OLQ.0000000000001271
    An online assessment among -social media-using YMSM found that 87% were willing to use HIV self-testing with online supervision (HIVSTOS). Correlates included never tested, having higher numbers of sexual partners and seeking partners online. HIVSTOS may be appropriate for YMSM who have high risks and may not access venue-based settings.
    MeSH terms: Humans; Male; Mass Screening; Sexual Partners; HIV Infections; Homosexuality, Male; Social Media
  5. Yusof AAM, Harun MN, Nasruddin FA, Syahrom A
    Int J Sports Med, 2020 Aug 25.
    PMID: 32842154 DOI: 10.1055/a-1231-5268
    According to numerous studies, rowing performance is influenced by several factors including rower's biomechanics, rower's physiology, the force generated and stroke style. However, there is a missing gap linking such factors with rowing performance in the available literature. This paper aims to investigate the rowing mechanism in terms of rower anthropometry and physiology, which can impact its biomechanics and performance. The corresponding hydrodynamic force generated by the oar blade to accelerate the boat is also considered in the current study. To test the objectives, systematical online searching was conducted in search of the inclusion literature criteria. All included studies used Preferred Reporting item for Systematic Review and Meta-analysis (PRISMA) guidelines to obtain the final collection of articles for this review. In order to rate the quality of the articles, risk bias assessment was performed. A total of 35 studies were included in the assessment. The studies discussed the aspects of anthropometry and physiological of the rower, the biomechanics of the rower, corresponding hydrodynamic force on the oar blade and the rowing mechanism concerning boat performance. Based on the information obtained, an understanding of the important aspects of the rowing mechanism was achieved to provide an update for comprehensive improvement.
    MeSH terms: Anthropometry; Ships; Risk Assessment; Stroke; Hydrodynamics
  6. Zhang Y, Zhou L, Zhang C, Show PL, Du A, Fu J, et al.
    Carbohydr Polym, 2020 Nov 01;247:116670.
    PMID: 32829798 DOI: 10.1016/j.carbpol.2020.116670
    With the growing interest in food safety and in environmental protection, it is more attractive to develop novel biodegradable packaging films. In this regard, one new blending film was prepared with curdlan (CD)/polyvinyl alcohol (PVA)/thyme essential oil. Our results demonstrated that the mechanical properties of the blending film were the best when the ratio of the CD and PVA was 4:1. Further, the barrier properties of the film were optimized by incorporating with thyme essential oil. It was proved that not only water vapor permeability was lower, but also the elongation at break was improved, when 2% (w/w) thyme essential oil used. The potential interactions of the film matrix were analyzed by FTIR, XRD and Cryo-scanning electron microscopy. Importantly, both the antioxidant activity and antibacterial activity were improved. Finally, the blending film was employed for the preservation of chilled meat, while the shelf life was extended up to 10 days.
    MeSH terms: Anti-Bacterial Agents; Antioxidants; Conservation of Natural Resources; Meat; Microscopy, Electron, Scanning; Oils, Volatile; Permeability; Polyvinyl Alcohol; Steam; Spectroscopy, Fourier Transform Infrared; Thymus Plant; beta-Glucans; Food Safety
  7. Musa N, Wong TW
    Carbohydr Polym, 2020 Nov 01;247:116673.
    PMID: 32829801 DOI: 10.1016/j.carbpol.2020.116673
    Microencapsulation of polysaccharidic nanoparticles is met with nanoscale and biological performance changes. This study designs soft agglomerates as nanoparticle vehicle without nanoparticles undergoing physical processes that alter their geometry. The nanoparticles were made of high molecular weight chitosan/pectin with covalent 5-fluorouracil/folate. Nanoparticle aggregation vehicle was prepared from low molecular weight chitosan. The nanoparticles and aggregation vehicle were blended in specific weight ratios to produce soft agglomerates. Nanoparticles alone are unable to agglomerate. Adding aggregation vehicle (< 2 μm) promoted soft agglomeration with nanoparticles deposited onto its surfaces with minimal binary coalescence. The large and rough-surfaced aggregation vehicle promoted nanoparticles deposition and agglomeration. A rounder vehicle allowed assembly of nanoparticles-on-aggregation vehicle into agglomerates through interspersing smaller between larger populations. Soft agglomeration reduced early drug release, and was responsive to intracapsular sodium alginate coat to further sustain drug release. The soft agglomerates can serve as a primary oral colon-specific vehicle.
    MeSH terms: Alginates; Colon; Excipients; Fluorouracil; Folic Acid; Molecular Weight; Pectins; Chitosan; Nanoparticles; Physical Phenomena; Drug Liberation
  8. Chieng CCY, Daud HM, Yusoff FM, Thompson KD, Abdullah M
    J Fish Dis, 2020 Oct;43(10):1249-1258.
    PMID: 32830331 DOI: 10.1111/jfd.13222
    Groupers are popular aquaculture species in South-East Asia, but their cultivation is affected by infectious disease outbreaks. Mucosa-associated lymphoid tissues provide a first-line defence against pathogens; however, few studies are available relating to cellular or proteomic responses of mucosal immunity in grouper. Skin, gill and intestine were sampled from brown-marbled grouper Epinephelus fuscoguttatus (Forsskål, 1775) at 4 and 96 hr post-infection (hpi) and 7 days post-infection (dpi) following intraperitoneal infection with Vibrio harveyi, and stained with haematoxylin/eosin and Alcian Blue/periodic acid-Schiff. Skin mucus was analysed by 2D-gel electrophoresis, and proteins modulated by the bacterial infection identified. In the infected fish, significant increases in sacciform cells in skin and increased levels of nucleoside diphosphate kinase in mucus were detected at 4 hpi. At 96 hpi, goblet cells containing acidic mucins significantly increased in the intestine, while those containing mixed mucins increased in skin and gills of infected fish. Proteasome subunit alpha type-I and extracellular Cu/Zn superoxide dismutase levels also increased in mucus. Rodlet and mast cells did not appear to respond to the infection. Mucosal tissues of grouper appeared actively involved in response to Vibrio infection. This information may help future research on improving grouper health, production and vaccine development.
    MeSH terms: Alcian Blue; Animals; Eosine Yellowish-(YS); Gills; Hematoxylin; Mast Cells; Mucins; Nucleoside-Diphosphate Kinase; Periodic Acid; Vibrio Infections; Immunity, Mucosal; Goblet Cells; Proteomics; Proteasome Endopeptidase Complex; Superoxide Dismutase-1
  9. Abd Razak N, Yeap SK, Alitheen NB, Ho WY, Yong CY, Tan SW, et al.
    Integr Cancer Ther, 2020 8 25;19:1534735420935625.
    PMID: 32830560 DOI: 10.1177/1534735420935625
    Eupatorin is a polymethoxy flavone extracted from Orthosiphon stamineus and was reported to exhibit cytotoxic effects on several cancer cell lines. However, its effect as an anti-breast cancer agent in vivo has yet to be determined. This study aims to elucidate the potential of eupatorin as an anti-breast cancer agent in vivo using 4T1 challenged BALB/c mice model. In this article, BALB/c mice (20-22 g) challenged with 4T1 cells were treated with 5 mg/kg or 20 mg/kg eupatorin, while the untreated and healthy mice were fed with olive oil (vehicle) via oral gavage. After 28 days of experiment, the mice were sacrificed and blood was collected for serum cytokine assay, while tumors were harvested to extract RNA and protein for gene expression assay and hematoxylin-eosin staining. Organs such as spleen and lung were harvested for immune suppression and clonogenic assay, respectively. Eupatorin (20 mg/kg) was effective in delaying the tumor development and reducing metastasis to the lung compared with the untreated mice. Eupatorin (20 mg/kg) also enhanced the immunity as the population of NK1.1+ and CD8+ in the splenocytes and the serum interferon-γ were increased. Concurrently, eupatorin treatment also has downregulated the expression of pro-inflammatory and metastatic related genes (IL-1β. MMP9, TNF-α, and NF-κB). Thus, this study demonstrated that eupatorin at the highest dosage of 20 mg/kg body weight was effective in delaying the 4T1-induced breast tumor growth in the animal model.
    MeSH terms: Animals; Female; Flavonoids; Humans; Mice, Inbred BALB C; Cell Line, Tumor; Mice
  10. Hamdan NKA, Lean QY, Neoh CF, Abdullah AH, Lim SM, Ramasamy K, et al.
    PMID: 32831870 DOI: 10.1155/2020/5713134
    Introduction: Facial candling is a traditional method used for relieving symptoms of allergic rhinitis (AR). This study aims to investigate the knowledge and perception of facial candling in a sample of staff and students in a public university in Malaysia.

    Methods: An online questionnaire survey method was used. Based on sample size calculation, a total of 1,508 UiTM staff and students from ten selected campuses of Universiti Teknologi MARA (UiTM) were invited to participate in this survey. An up-to-date e-mail list of staff in the selected campuses was used as the sampling frame for the study, whereas the students were recruited from the official university student Facebook portal.

    Results: A total of 788 respondents participated in this survey, 72.2% of them knew about facial candling, though only 35.4% had tried the treatment. Approximately one-fifth of respondents agreed that facial candling might treat AR. It was found that a higher number of users than nonusers agreed that facial candling was a traditional medicine (78.9% vs 55.0%); could be used on the face and ears (83.5% vs 45.4%); and could be self-administered at home (83.5 vs 45.4%). Interestingly, more than half of them were uncertain about its long-term effects and adverse reactions.

    Conclusion: This study confirms the facial candling use among patients with AR although the percentage is low. The patients and general public need to be better informed about the use of facial candling in AR and its associated risks.

    MeSH terms: Humans; Malaysia; Medicine, Traditional; Surveys and Questionnaires; Students; Universities; Sample Size; Electronic Mail; Social Media; Rhinitis, Allergic
  11. Mohd Dom NS, Yahaya N, Adam Z, Nik Abd Rahman NMA, Hamid M
    PMID: 32831872 DOI: 10.1155/2020/6374632
    The present study aimed to evaluate the potential of standardized methanolic extracts from seven Ficus deltoidea varieties in inhibiting the formation of AGEs, protein oxidation, and their antioxidant effects. The antiglycation activity was analyzed based on the inhibition of AGEs, fructosamine, and thiol groups level followed by the inhibition of protein carbonyl formation. The antioxidant activity (DPPH radical scavenging activity and reducing power assay) and total phenolic contents were evaluated. After 28 days of induction, all varieties of Ficus deltoidea extracts significantly restrained the formation of fluorescence AGEs by 4.55-5.14 fold. The extracts also reduced the fructosamine levels by 47.0-86.5%, increased the thiol group levels by 64.3-83.7%, and inhibited the formation of protein carbonyl by 1.36-1.76 fold. DPPH radical scavenging activity showed an IC50 value of 66.81-288.04 μg/ml and reducing power activity depicted at 0.02-0.24 μg/ml. The extent of phenolic compounds present in the extracts ranged from 70.90 to 299.78 mg·GAE/g. Apart from that, correlation studies between the activities were observed. This study revealed that seven varieties of Ficus deltoidea have the potential to inhibit AGEs formation and possess antioxidant activity that might be attributed to the presence of phenolic compounds.
    MeSH terms: Methanol; Antioxidants; Fluorescence; Oxidation-Reduction; Phenols; Plant Extracts; Reference Standards; Sulfhydryl Compounds; Fructosamine; Inhibitory Concentration 50; Ficus; Protein Carbonylation
  12. Seal A, Reddy PPN, Chaithanya P, Meghana A, Jahnavi K, Krejcar O, et al.
    Comput Math Methods Med, 2020;2020:8303465.
    PMID: 32831902 DOI: 10.1155/2020/8303465
    Human emotion recognition has been a major field of research in the last decades owing to its noteworthy academic and industrial applications. However, most of the state-of-the-art methods identified emotions after analyzing facial images. Emotion recognition using electroencephalogram (EEG) signals has got less attention. However, the advantage of using EEG signals is that it can capture real emotion. However, very few EEG signals databases are publicly available for affective computing. In this work, we present a database consisting of EEG signals of 44 volunteers. Twenty-three out of forty-four are females. A 32 channels CLARITY EEG traveler sensor is used to record four emotional states namely, happy, fear, sad, and neutral of subjects by showing 12 videos. So, 3 video files are devoted to each emotion. Participants are mapped with the emotion that they had felt after watching each video. The recorded EEG signals are considered further to classify four types of emotions based on discrete wavelet transform and extreme learning machine (ELM) for reporting the initial benchmark classification performance. The ELM algorithm is used for channel selection followed by subband selection. The proposed method performs the best when features are captured from the gamma subband of the FP1-F7 channel with 94.72% accuracy. The presented database would be available to the researchers for affective recognition applications.
    MeSH terms: Machine Learning; Algorithms*; Brain/anatomy & histology; Brain/physiology; Electroencephalography/methods*; Electroencephalography/statistics & numerical data; Emotions/classification*; Emotions/physiology; Female; Humans; Male; Photic Stimulation; Video Recording; Databases, Factual; Neural Networks (Computer); Computational Biology; Benchmarking; Mathematical Concepts; Brain Waves/physiology
  13. Kong BH, Teoh KH, Tan NH, Tan CS, Ng ST, Fung SY
    PeerJ, 2020;8:e9650.
    PMID: 32832273 DOI: 10.7717/peerj.9650
    Background: Lignosus tigris, a recently discovered species of the unique Lignosus family, has been traditionally used by the indigenous communities in Peninsular Malaysia to treat various ailments and as an alternative medicine for cancer treatment. The L. tigris cultivar sclerotia (Ligno TG-K) was found to contain numerous bioactive compounds with beneficial biomedicinal properties and the sclerotial extract exhibited potent antioxidant activity. However, the anticancer property of the Ligno TG-K including in vitro and in vivo antitumor effects as well as its anticancer active compounds and the mechanisms has yet to be investigated.

    Methods: The cytotoxicity of the Ligno TG-K against human breast (MCF7), prostate (PC3) and lung (A549) adenocarcinoma cell lines was evaluated using MTT cytotoxicity assay. The cytotoxic mechanisms of the active high molecular weight proteins (HMWp) fraction were investigated through detection of caspases activity and apoptotic-related proteins expression by Western blotting. The in vivo antitumor activity of the isolated HMWp was examined using MCF7 mouse xenograft model. Shotgun LC-MS/MS analysis was performed to identify the proteins in the HMWp.

    Results and Discussion: Cold water extract of the sclerotia inhibited proliferation of MCF7, A549 and PC3 cells with IC50 ranged from 28.9 to 95.0 µg/mL. Bioassay guided fractionation of the extract revealed that HMWp exhibited selective cytotoxicity against MCF7 cells via induction of cellular apoptosis by the activation of extrinsic and intrinsic signaling pathways. HMWp activated expression of caspase-8 and -9 enzymes, and pro-apoptotic Bax protein whilst inhibiting expression of tumor survivor protein, Bcl-2. HMWp induced tumor-cell apoptosis and suppressed growth of tumor in MCF-7 xenograft mice. Lectins, serine proteases, RNase Gf29 and a 230NA deoxyribonuclease are the major cytotoxic proteins that accounted for 55.93% of the HMWp.

    Conclusion: The findings from this study provided scientific evidences to support the traditional use of the L. tigris sclerotia for treatment of breast cancer. Several cytotoxic proteins with high abundance have been identified in the HMWp of the sclerotial extract and these proteins have potential to be developed into new anticancer agents or as adjunct cancer therapy.

    MeSH terms: Animals; Antioxidants; Breast Neoplasms; Chromatography, Liquid; Humans; Male; Molecular Weight; Prostate; Ribonucleases; Inhibitory Concentration 50; Lectins; bcl-2-Associated X Protein; Mice; Caspase 8; Serine Proteases; MCF-7 Cells; Heterografts
  14. Chuah R, Gopinath SCB, Anbu P, Salimi MN, Yaakub ARW, Lakshmipriya T
    3 Biotech, 2020 Aug;10(8):364.
    PMID: 32832325 DOI: 10.1007/s13205-020-02365-4
    In this study, biological deoxygenation of graphene oxide (GO) using an Eclipta prostrata phytoextract was performed via the infusion method. The presence of oxide groups on the surface of graphene and removal of oxides groups by reduction were characterized through morphological and structural analyses. Field emission scanning electron microscopy images revealed that the synthesized GO and rGO were smooth and morphologically sound. Transmission electron microscopy images showed rGO developing lattice fringes with smooth edges and transparent sheets. Atomic force microscopy images showed an increase in the surface roughness of graphite oxide (14.29 nm) compared with that of graphite (1.784 nm) due to the presence of oxide groups after oxidation, and the restoration of surface roughness to 2.051 nm upon reduction. Energy dispersive X-ray analysis indicated a difference in the carbon/oxygen ratio between GO (1.90) and rGO (2.70). Fourier-transform infrared spectroscopy spectrum revealed peak stretches at 1029, 1388, 1578, and 1630 cm-1 for GO, and a decrease in the peak intensity after reduction that confirmed the removal of oxide groups. X-ray photoelectron microscopy also showed a decrease in the intensity of oxygen peak after reduction. In addition, thermogravimetric analysis suggested that rGO was less thermally stable than graphite, graphite oxide, and GO, with rGO decomposing after heating at temperatures ranging from room temperature to 600 °C.
  15. Mei CF, Faller EM, Chuan LX, Gabriel JS
    Ann Glob Health, 2020 08 03;86(1):90.
    PMID: 32832384 DOI: 10.5334/aogh.2859
    Background and Purpose: Food insecurity exists whenever accessibility to nutritious food is limited. It affects a person's health with regards to nutritional status, indicated by malnourishment or overnutrition. This study aims to study the relationship between household income, household food insecurity, and weight status of migrant workers in Klang Valley, Selangor.

    Method: A cross-sectional study involving a convenience sampling of 125 documented migrant workers from five selected countries was conducted. A researcher-administered questionnaire consisting of socio-demographic questions, three-day 24-hour dietary recall (3DR), and nine-item Household Food Insecurity Access Scale was used. Anthropometric measurements, including body weight, height, and waist circumference, were taken.

    Findings: About 57.6% of the households studied were food insecure (24.8% mildly, 29.6% moderately, and 3.2% severely). Burmese were found to have the highest rate of household food insecurity (96%). The majority of the migrant workers were of normal weight (68.0%). No significant relationship was found between monthly household income and household food security status (p = 0.475), as well as between household food security status and weight status (p = 0.535).

    Conclusion: Results imply that food security status affects certain nutrient intake among migrant workers. There were no significant associations between variables. Interventions focusing on nutritional education on food choices and implementation on health policy are recommended. Further studies should consider the accessibility, nutritional-related diseases, and dietary aspects of migrant workers, which are risk factors for food insecurity.

    MeSH terms: Body Weight; Energy Intake; Cross-Sectional Studies; Diet; Food Supply; Health Policy; Humans; Nutritional Status; Surveys and Questionnaires; Risk Factors; Transients and Migrants; Malnutrition; Overnutrition; Waist Circumference
  16. Pal A, Roy S, Kumar A, Mahmood S, Khodapanah N, Thomas S, et al.
    ACS Omega, 2020 Aug 18;5(32):19968-19977.
    PMID: 32832751 DOI: 10.1021/acsomega.0c01228
    This present study investigated the effect of Captisol, a chemically modified cyclodextrin, on the in vitro dissolution of glimepiride. We prepared glimepiride-Captisol complexes of different mass ratios (1:1, 1:2, and 1:3 w/w) by a physical mixing or freeze-drying technique, and found that complexation with Captisol enhanced the water solubility of glimepiride. Molecular docking and dynamic simulation predicted complex formation; at the same time, Fourier transform infrared spectroscopy, differential scanning calorimetry, powder X-ray diffractometry, and scanning electron microscope indicated molecular interactions that support complexation. We also found that an inclusion complex was better than a physical mixture in enhancing the complexation of glimepiride with Captisol and enhancing water solubility. Phase solubility study of the glimepiride-Captisol complex showed an AL-type profile, implying the formation of a 1:1 inclusion complex. The study also revealed that pH influenced the stability of the complex because the stability constant of the glimepiride-Captisol complex was higher in distilled water of pH ∼6.0 than in phosphate buffer of pH 7.2.
    MeSH terms: Calorimetry, Differential Scanning; Cyclodextrins; Freeze Drying; Hydrogen-Ion Concentration; Microscopy, Electron, Scanning; Phosphates; Solubility; Sulfonylurea Compounds; X-Rays; Spectroscopy, Fourier Transform Infrared; beta-Cyclodextrins; Molecular Docking Simulation
  17. Abdulelah H, Negash BM, Yekeen N, Al-Hajri S, Padmanabhan E, Al-Yaseri A
    ACS Omega, 2020 Aug 18;5(32):20107-20121.
    PMID: 32832765 DOI: 10.1021/acsomega.0c01738
    The influence of an anionic surfactant, a cationic surfactant, and salinity on adsorbed methane (CH4) in shale was assessed and modeled in a series of systematically designed experiments. Two cases were investigated. In case 1, the crushed Marcellus shale samples were allowed to react with anionic sodium dodecyl sulfate (SDS) and brine. In case 2, another set of crushed Marcellus shale samples were treated with cetyltrimethylammonium bromide (CTAB) and brine. The surfactant concentration and salinity of brine were varied following the Box-Behnken experimental design. CH4 adsorption was then assessed volumetrically in the treated shale at varying pressures (1-50 bar) and a constant temperature of 30 °C using a pressure equilibrium cell. Mathematical analysis of the experimental data yielded two separate models, which expressed the amount of adsorbed CH4 as a function of SDS/CTAB concentration, salinity, and pressure. In case 1, the highest amount of adsorbed CH4 was about 1 mmol/g. Such an amount was achieved at 50 bar, provided that the SDS concentration is kept close to its critical micelle concentration (CMC), which is 0.2 wt %, and salinity is in the range of 0.1-20 ppt. However, in case 2, the maximum amount of adsorbed CH4 was just 0.3 mmol/g. This value was obtained at 50 bar and high salinity (∼75 ppt) when the CTAB concentration was above the CMC (>0.029 wt %). The findings provide researchers with insights that can help in optimizing the ratio of salinity and surfactant concentration used in shale gas fracturing fluid.
    MeSH terms: Adsorption; Anions; Methane; Micelles; Pulmonary Surfactants; Research Design; Salts; Sodium Dodecyl Sulfate; Surface-Active Agents; Temperature; Salinity; Natural Gas
  18. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2020;80(8):718.
    PMID: 32834020 DOI: 10.1140/epjc/s10052-020-8166-5
    Central exclusive and semiexclusive production of pairs is measured with the CMS detector in proton-proton collisions at the LHC at center-of-mass energies of 5.02 and 13TeV. The theoretical description of these nonperturbative processes, which have not yet been measured in detail at the LHC, poses a significant challenge to models. The two pions are measured and identified in the CMS silicon tracker based on specific energy loss, whereas the absence of other particles is ensured by calorimeter information. The total and differential cross sections of exclusive and semiexclusive central production are measured as functions of invariant mass, transverse momentum, and rapidity of the system in the fiducial region defined as transverse momentum and pseudorapidity . The production cross sections for the four resonant channels , , , and are extracted using a simple model. These results represent the first measurement of this process at the LHC collision energies of 5.02 and 13TeV.
  19. Bukar AL, Tan CW, Yiew LK, Ayop R, Tan WS
    Energy Convers Manag, 2020 Oct 01;221:113161.
    PMID: 32834297 DOI: 10.1016/j.enconman.2020.113161
    Off-grid electrification of remote communities using sustainable energy systems (SESs) is a requisite for realizing sustainable development goals. Nonetheless, the capacity planning of the SESs is challenging as it needs to fulfil the fluctuating demand from a long-term perspective, in addition to the intermittency and unpredictable nature of renewable energy sources (RESs). Owing to the nonlinear and non-convex nature of the capacity planning problem, an efficient technique must be employed to achieve a cost-effective system. Existing techniques are, subject to some constraints on the derivability and continuity of the objective function, prone to premature convergence, computationally demanding, follows rigorous procedures to fine-tune the algorithm parameters in different applications, and often do not offer a fair balance during the exploitation and exploration phase of the optimization process. Furthermore, the literature review indicates that researchers often do not implement and examine the energy management scheme (EMS) of a microgrid while computing for the capacity planning problem of microgrids. This paper proposes a rule-based EMS (REMS) optimized by a nature-inspired grasshopper optimization algorithm (GOA) for long-term capacity planning of a grid-independent microgrid incorporating a wind turbine, a photovoltaic, a battery (BT) bank and a diesel generator (

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    ). In which, a rule-based algorithm is used to implement an EMS to prioritize the usage of RES and coordinate the power flow of the proposed microgrid components. Subsequently, an attempt is made to explore and confirm the efficiency of the proposed REMS incorporated with GOA. The ultimate goal of the objective function is to minimize the cost of energy (COE) and the deficiency of power supply probability (DPSP). The performance of the REMS is examined via a long-term simulation study to ascertain the REMS resiliency and to ensure the operating limit of the BT storage is not violated. The result of the GOA is compared with particle swarm optimization (PSO) and a cuckoo search algorithm (CSA). The simulation results indicate that the proposed technique's superiority is confirmed in terms of convergence to the optimal solution. The simulation results confirm that the proposed REMS has contributed to better adoption of a cleaner energy production system, as the scheme significantly reduces fuel consumption,


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    2

    emission and COE by 92.4%, 92.3% and 79.8%, respectively as compared to the conventional

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    . The comparative evaluation of the algorithms shows that REMS-GOA yields a better result as it offers the least COE (objective function), at $0.3656/kW h, as compared to the REMS-CSA at $0.3662/kW h and REMS-PSO at $0.3674/kW h, for the desired DPSP of 0%. Finally, sensitivity analysis is performed to highlight the effect of uncertainties on the system inputs that may arise in the future.
    MeSH terms: Algorithms; Animals; Cost-Benefit Analysis; Goals; Grasshoppers; Electric Power Supplies; Probability; Uncertainty; Renewable Energy
  20. Yekeen N, Malik AA, Idris AK, Reepei NI, Ganie K
    J Pet Sci Eng, 2020 Dec;195:107591.
    PMID: 32834477 DOI: 10.1016/j.petrol.2020.107591
    In this study, a natural surfactant, saponin was isolated from soapnut (Sapindus Mukorossi). The extracted surfactant was characterized by Fourier-transform infrared spectroscopy (FTIR) analysis. The effectiveness of the isolated surfactant as EOR agent was evaluated from foam generation/stabilization properties, wettability alteration of the rock surfaces, as well as oil-water interfacial tension (IFT) reduction characteristics. The performance of the extracted saponin was compared with that of a commercial saponin and sodium dodecyl sulfate (SDS). The foaming properties of the saponin with carbon dioxide (CO2) was characterized using Teclis Foamscan instrument at room condition and 60 °C. The IFT and contact angles at room conditions and reservoir conditions were measured using KRŰSS Drop Shape Analyzer (DSA 25 and DSA 100) via pendant drop and sessile drop techniques respectively. The foamability of the saponin-stabilized foam was good at ambient condition and 60 °C. Moreover, the time taken for almost 100% liquid drainage was higher in saponin-stabilized foam than the SDS-stabilized foam. The optimum concentration for attaining maximum foam stability decreased from 0.4 wt% at room temperature to 0.1 wt% at 60 °C. Signifying that the quantity of the surfactant to be used in foam generation could reduce at high temperature. The isolated saponin exhibited relatively good interfacial activities individually and in synergistic interaction with silicon dioxide (SiO2) nanoparticles at reservoir conditions. Precisely, at 8 MPa and 80 °C, the crude-oil water IFT was reduced from 23.24 mN/m to 1.59 mN/m (about 93.2%) by 0.2 wt% saponin concentration. The IFT was further reduced to 0.87 mN/m (about 96.3%) by a mixed system of 0.5 wt% saponin and 0.05 wt% SiO2 nanoparticles concentration. Increasing IFT with increasing temperature were observed at very high temperature due to phase separation resulting from clouding phenomenon. However, the clouding temperature increased with 0.1 wt% saponin concentration, and in presence of SiO2 nanoparticles (0.05 wt% and 0.1 wt%). The study suggests that the extracted saponin could be considered as supplementary alternative to conventional EOR surfactants.
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