Browse publications by year: 2022

  1. Du C, Adjepong M, Zan MCH, Cho MJ, Fenton JI, Hsiao PY, et al.
    Nutrients, 2022 Sep 20;14(19).
    PMID: 36235535 DOI: 10.3390/nu14193882
    We thank Kuo et al. for their comments [...].
    MeSH terms: Feeding Behavior*; Sex Factors; Sleep; Stress, Psychological; Body Mass Index
  2. Shyam S, Lee KX, Tan ASW, Khoo TA, Harikrishnan S, Lalani SA, et al.
    Nutrients, 2022 Oct 02;14(19).
    PMID: 36235756 DOI: 10.3390/nu14194104
    Personalized nutrition is an approach that tailors nutrition advice to individuals based on an individual's genetic information. Despite interest among scholars, the impact of this approach on lifestyle habits and health has not been adequately explored. Hence, a systematic review of randomized trials reporting on the effects of personalized nutrition on dietary, physical activity, and health outcomes was conducted. A systematic search of seven electronic databases and a manual search resulted in identifying nine relevant trials. Cochrane's Risk of Bias was used to determine the trials' methodological quality. Although the trials were of moderate to high quality, the findings did not show consistent benefits of personalized nutrition in improving dietary, behavioral, or health outcomes. There was also a lack of evidence from regions other than North America and Europe or among individuals with diseases, affecting the generalizability of the results. Furthermore, the complex relationship between genes, interventions, and outcomes may also have contributed to the scarcity of positive findings. We have suggested several areas for improvement for future trials regarding personalized nutrition.
    MeSH terms: Diet*; Humans; Life Style; Nutritional Status; Exercise*; Randomized Controlled Trials as Topic
  3. Amaechi CV, Reda A, Kgosiemang IM, Ja'e IA, Oyetunji AK, Olukolajo MA, et al.
    Sensors (Basel), 2022 Sep 25;22(19).
    PMID: 36236369 DOI: 10.3390/s22197270
    Recent activities in the oil and gas industry have shown an increasing need for monitoring engagements, such as in shipping, logistics, exploration, drilling, or production. Hence, there is a need to have asset management of these offshore assets (or facilities). Much of the offshore infrastructure is currently approaching or past its operational life expectancy. The study presents an overview on asset management of offshore facilities towards monitoring, safe practices, maintenance, and sustainability. This study outlines the major considerations and the steps to take when evaluating asset life extensions for an aging offshore structure (or asset). The design and construction of offshore structures require some materials that are used to make the structural units, such as offshore platform rigs, ships, and boats. Maintaining existing assets in the field and developing new platforms that are capable of extracting future oil and gas resources are the two key issues facing the offshore sector. This paper also discusses fault diagnosis using sensors in the offshore facilities. The ocean environment is constantly corrosive, and the production activities demand extremely high levels of safety and reliability. Due to the limited space and remote location of most offshore operations, producing cost-effective, efficient, and long-lasting equipment necessitates a high level of competence. This paper presents the guidelines on asset monitoring, sustainable maintenance, and safety practices for offshore structures. In this study, the management of offshore structures were also presented with some discussions on fault monitoring using sensors. It also proposes sustainable asset management approaches as guidelines that are advised, with policy implications.
    MeSH terms: Caustics*; Industry; Ships; Reproducibility of Results
  4. Aziz NA, Long F, Bhuiyan MA, Rahman MK
    Front Psychol, 2022;13:961464.
    PMID: 36237672 DOI: 10.3389/fpsyg.2022.961464
    The COVID-19 pandemic has deeply influenced the tourism and hospitality industry, and it has also reshaped people's travel preferences and related behaviors. As a result, how prospective travelers perceive travel constraints and their effects on future travel behaviors may have changed to some extent. Besides, such perception arguably varies across gender. Therefore, this research examines the interplay between travel constraints, gender, and travel intentions for facilitating robust tourism recovery by revisiting the Leisure Constraints Model (LCM) from a gender perspective. Data were collected through a survey from 357 Malaysian prospective travelers. By conducting path analysis and multigroup analysis (MGA), it is found that structural and interpersonal constraints impose indirect effects on travel intentions (mediated by intrapersonal constraints), and gender moderating the effect of structural cost on intrapersonal constraints and effect of intrapersonal constraints on travel intentions. Based on these findings, this research provides theoretical and practical implications into how to adjust their marketing strategies and travel products during the era of "new normal" for tourism policy makers, destination marketers, and related businesses.
  5. Alajmi B, Karobari MI, Aldowah O
    Clin Case Rep, 2022 Oct;10(10):e6405.
    PMID: 36237942 DOI: 10.1002/ccr3.6405
    Proper removal of the diseased tissue, debriding the canal system, and sealing the defect or cavity, the surgeon prevents or reduces the spread of microorganisms within the periradicular tissues. Treatment modalities following the failure of root canal treatment (RCT) are root canal retreatment (ReRCT). Regeneration of periapical defects may have a significant problem in periradicular surgery. In such circumstances, the gingival connective tissue can proliferate, or the oral epithelium can migrate into the defect, preventing the development of normal trabecular bone. Hard tissue can be restored using guided tissue regeneration (GTR) in conjunction with endodontic treatment for endodontic-periodontal lesions. Treatment of large periapical defects using GTR increases overall treatment success.
  6. Li D, Luque A, Lehtinen NG, Gordillo-Vázquez FJ, Neubert T, Lu G, et al.
    Geophys Res Lett, 2022 Jul 16;49(13):e2022GL098938.
    PMID: 36245952 DOI: 10.1029/2022GL098938
    How lightning initiates inside thunderclouds remains a major puzzle of atmospheric electricity. By monitoring optical emissions from thunderstorms, the Atmosphere-Space Interactions Monitor (ASIM) onboard the International Space Station is providing new clues about lightning initiation by detecting Blue LUminous Events (BLUEs), which are manifestations of electrical corona discharges that sometimes precedes lightning. Here we combine optical and radio observations from a thunderstorm near Malaysia to uncover a new type of event containing multiple optical and radio pulses. We find that the first optical pulse coincides with a strong radio signal in the form of a Narrow Bipolar Event (NBE) but subsequent optical pulses, delayed some milliseconds, have weaker radio signals, possibly because they emanate from a horizontally oriented electrical discharges which does not trigger full-fledged lightning. Our results cast light on the differences between isolated and lightning-initiating electrical discharges.
  7. Salman NH, Mok Sam L, Ador K, Binjamin B, Johny-Hasbulah MIJ, Benedick S
    J Toxicol, 2022;2022:4478082.
    PMID: 36246191 DOI: 10.1155/2022/4478082
    Honey is a natural product of bees, and its chemical composition depends on the nectar sources of the surrounding flora as well as environmental factors. However, keeping hives in areas polluted with heavy metals can affect the quality of bee products such as honey. To date, there have been very few studies on the health risks of consuming honey at various locations in the Malaysian state of Sabah, Borneo, in relation to food standards and heavy metal contamination of honey from the stingless bee, Heterotrigona itama in association with pollutant sources. A total of 63 samples of raw and unprocessed honey were collected directly from beekeepers producing honey at five sites in the industrial areas. All selected heavy metals were measured using an inductively coupled plasma optical emission spectrophotometer (ICP-OES). Overall, the most frequently detected element was Zn (0.090 mg/kg), followed by Pb (0.012 mg/kg), As (0.004 mg/kg), and Cr (0.003 mg/kg), while Cd (0.001 mg/kg) was the lowest element in honey from all areas. With the exception of Cr and Zn, a significant correlation was found between PCA factor score 1 and heavy metal concentration in honey for Pb, Cd, and As, suggesting that the source of pollution for these metal elements was from hives closer to major roads, cities/town, petrochemical hub, and power plants. Although the heavy metal concentrations in the honey samples did not exceed the food standard limits and therefore do not pose a health risk, the observed increase in heavy metal concentrations in honey in industrial areas could pose a potential risk in the future due to the growing interest in rearing of stingless bees for honey production in these areas of Sabah.
  8. Washif JA, Pyne DB, Sandbakk Ø, Trabelsi K, Aziz AR, Beaven CM, et al.
    Biol Sport, 2022 Oct;39(4):1103-1115.
    PMID: 36247962 DOI: 10.5114/biolsport.2022.117576
    Ramadan intermittent fasting during the COVID-19 lockdown (RIFL) may present unique demands. We investigated training practices (i.e., training load and training times) of athletes, using pre-defined survey criteria/questions, during the 'first' COVID-19 lockdown, comparing RIFL to lockdown-alone (LD) in Muslim athletes. Specifically, a within-subject, survey-based study saw athletes (n = 5,529; from 110 countries/territories) training practices (comparing RIFL to LD) explored by comparative variables of: sex; age; continent; athlete classification (e.g., world-class); sport classification (e.g., endurance); athlete status (e.g., professional); and level of training knowledge and beliefs/attitudes (ranked as: good/moderate/poor). During RIFL (compared to LD), athlete perceptions (ranges presented given variety of comparative variables) of their training load decreased (46-62%), were maintained (31-48%) or increased (2-13%). Decreases (≥ 5%, p < 0.05) affected more athletes aged 30-39 years than those 18-29 years (60 vs 55%); more national than international athletes (59 vs 51%); more team sports than precision sports (59 vs 46%); more North American than European athletes (62 vs 53%); more semi-professional than professional athletes (60 vs 54%); more athletes who rated their beliefs/attitudes 'good' compared to 'poor' and 'moderate' (61 vs 54 and 53%, respectively); and more athletes with 'moderate' than 'poor' knowledge (58 vs 53%). During RIFL, athletes had different strategies for training times, with 13-29% training twice a day (i.e., afternoon and night), 12-26% at night only, and 18-36% in the afternoon only, with ranges depending on the comparative variables. Training loads and activities were altered negatively during RIFL compared to LD. It would be prudent for decision-makers responsible for RIFL athletes to develop programs to support athletes during such challenges.
  9. Said MAM, Wellun Z, Khamis NK
    Iran J Public Health, 2022 Aug;51(8):1706-1717.
    PMID: 36249108 DOI: 10.18502/ijph.v51i8.10251
    BACKGROUND: Occupational noise exposure is one of the environmental factors that pose safety and health risks among workers in factories. This systematic review focuses on the activities that cause noise hazards toward workers' heart rate, other physiological conditions, and strategies to prevent noise exposure in the manufacturing industry.

    METHODS: Through a comprehensive literature review, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Cochrane method were used. The appraisal of quality was conducted by using the Critical Appraisal Skills Programme (CASP) to fulfil the selected keywords.

    RESULTS: Occupational noise exposure not only affects the workers' most common issues, such as heart rate, but also other physiological factors, such as blood pressure. The outcome showed that different level of continuous noise exposure with high intensity decibels affects the heart rate of the workers. Source, path, receiver was recommended strategies for basic noise prevention in engineering control.

    CONCLUSION: Therefore, noise give significant effects towards human workers in related industry. Study related to noise effects towards heart rate performance led to future prevention and innovation.

  10. Khan J, E N, Mariatti M, Vilay V, Todo M
    J Ind Text, 2022 Jun;52:15280837221111175.
    PMID: 36249720 DOI: 10.1177/15280837221111175
    The coronavirus pandemic (COVID-19) is currently the biggest threat to human lives due to its rapid transmission rate causing severe damage to human health and economy. The transmission of viral diseases can be minimized at its early stages with proper planning and preventive practices. The use of facemask has proved to be most effective measure to curb the spread of virus along with social distancing and good hygiene practices. This necessitates more research on facemask technology to increase its filtration efficiencies and proper disposal, which can be accelerated with knowledge of the current manufacturing process and recent research in this field. This review article provides an overview of the importance of facemask, fundamentals of nonwoven fabrics, and its manufacturing process. It also covers topics related to recent research reported for improved facemask efficiencies and testing methods to evaluate the performance of facemask. The plastic waste associated with the facemask and measures to minimize its effect are also briefly described. A systematic understanding is given in order to trigger future research in this field to ensure that we are well equipped for any future pandemic.
  11. Arip M, Selvaraja M, R M, Tan LF, Leong MY, Tan PL, et al.
    Front Pharmacol, 2022;13:879495.
    PMID: 36249774 DOI: 10.3389/fphar.2022.879495
    Antimicrobial resistance (AMR) occurs when microbes no longer respond to any pharmacological agents, rendering the conventional antimicrobial agents ineffective. AMR has been classified as one of the top 10 life-threatening global health problems needed multilevel attention and global cooperation to attain the Sustainable Development Goals (SDGs) according to the World Health Organization (WHO), making the discovery of a new and effective antimicrobial agent a priority. The recommended treatments for drug-resistant microbes are available but limited. Furthermore, the transformation of microbes over time increases the risk of developing drug resistance. Hence, plant metabolites such as terpenes, phenolic compounds and alkaloids are widely studied due to their antibacterial, antiviral, antifungal and antiparasitic effects. Plant-derived antimicrobials are preferred due to their desirable efficacy and safety profile. Plant metabolites work by targeting microbial cell membranes, interfering with the synthesis of microbial DNA/RNA/enzymes and disrupting quorum sensing and efflux pump expression. They also work synergistically with conventional antibiotics to enhance antimicrobial effects. Accordingly, this review aims to identify currently available pharmacological therapies against microbes and AMR, as well as to discuss the importance of plant and secondary metabolites as a possible solution for AMR together with their mechanisms of action. All the information was obtained from government databases, WHO websites, PubMed, Springer, Google Scholar and Science Direct. Based on the information obtained, AMR is regarded as a significant warning to global healthcare. Plant derivatives such as secondary metabolites may be considered as potential therapeutic targets to mitigate the non-ending AMR.
  12. Esfahani A, Mohammadi Nafchi A, Baghaei H, Nouri L
    Food Sci Nutr, 2022 Oct;10(10):3293-3301.
    PMID: 36249982 DOI: 10.1002/fsn3.2918
    Nowadays, the development of pH-sensitive smart edible films using biopolymers and natural plant extracts (especially those rich in anthocyanins) has attracted much attention. Therefore, in this study, the intelligent edible film was produced and characterized using cassava starch and pomegranate peel powder (PPP) and the possibility of using production films to monitor the freshness of lamb meat. The smart films were prepared using different concentrations of PPP (2, 4, 6, and 8% w/w) and the solvent casting method. The results showed that the incorporation of PPP had a significant effect on the mechanical parameters of the starch films. With increasing the levels of PPP, the color of the films became darker and redder. Increasing the PPP levels also led to an increase in total phenol content (TPC) (from 0 to 13 mg GAE (gallic acid equivalent)/g) and antioxidant activity (from 0% to 70% DPPH (1,1-diphenyl-2-picryl hydrazyl) radical scavenging) of the produced films (p 
  13. Ismail NA, Shameli K, Mohamad Sukri SNA, Hara H, Teow SY, Moeini H
    Front Mol Biosci, 2022;9:995853.
    PMID: 36250022 DOI: 10.3389/fmolb.2022.995853
    The combination of graphene-based materials and inorganic nanoparticles for the enhancement of the nanomaterial properties is extensively explored nowadays. In the present work, we used a sonochemical method to synthesize a copper/reduced graphene oxide (Cu/RGO) nanocomposite using Australian honey and vitamin C as capping and reducing agents, respectively. The honey-mediated copper/reduced graphene oxide (H/Cu/RGO) nanocomposite was then characterized through UV-visible, XRD, HRTEM, and FTIR analysis. The copper nanoparticles (Cu-NPs) in the nanocomposite formed uniform spherical shapes with a size of 2.20 ± 0.70 nm, which attached to the reduced graphene oxide (RGO) layers. The nanocomposite could suppress bacterial growth in both types of bacteria strains. However, in this study, the nanocomposite exhibited good bactericidal activity toward the Gram-positive bacteria than the Gram-negative bacteria. It also showed a cytotoxic effect on the cancer colorectal cell line HCT11, even in low concentrations. These results suggested that the H/Cu/RGO nanocomposite can be a suitable component for biomedical applications.
  14. Wong QYA, Lim JJ, Ng JY, Malipeddi P, Teo WY, Lim YYE, et al.
    World Allergy Organ J, 2022 Oct;15(10):100704.
    PMID: 36267097 DOI: 10.1016/j.waojou.2022.100704
    BACKGROUND: Allergic rhinitis (AR) is characterized by the occurrence of at least 2 symptoms of nasal itching, nasal blockage, rhinorrhea, and sneezing, when not afflicted with a cold or flu, with defined atopic sensitization demonstrated by skin prick test or specific IgE responses. Besides the detriment to standard of living and economic burden of AR, both multicentre and single-cohort studies have observed an increase in AR prevalence in Asia over time.

    METHODS: In total, 12 872 individuals, with mean age 22.1 years (SD = 4.8), were recruited from universities in Singapore and Malaysia. Each participant provided epidemiological data based on an investigator-administered questionnaire adapted from the validated International Study of Allergies and Asthma in Childhood (ISAAC) protocol, and atopy status was determined using a skin prick test (SPT) performed by qualified staff. AR was diagnosed according to Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines and a positive SPT result.

    RESULTS: Sensitization (determined by SPT) to either Blomia tropicalis or Dermatophagoides pteronyssinus was prevalent in 66.5% of the cohort. Current rhinitis (manifesting ≥2 rhinitis symptoms, within the past 12 months) was observed in 48.9% of our population, while AR, which included atopy status, was estimated at 39.4%. Sneezing and rhinorrhea were the most common symptoms among AR cases. AR prevalence decreased with increasing age (OR: 0.979; 95% CI: 0.969-0.989), while male gender (OR: 2.053; 95% CI: 1.839-2.294), and a parental history of allergic diseases (OR: 2.750; 95% CI: 2.284-3.316) were significant risk factors for AR. Upon adjustment for age, gender, and parental history, housing type (OR: 0.632; 95% CI: 0.543-0.736) and income level (>$6000 vs

  15. Mohamad Alwi MA, Ahmad MN, Misnon II, Pauzi H, Normaya E
    RSC Adv, 2022 Sep 28;12(43):27793-27808.
    PMID: 36320253 DOI: 10.1039/d2ra05192c
    Thiosemicarbazone-linked 3-acetylpyridine (T3AP), was synthesized and tested on copper strips in hydrochloric acid. Gravimetric measurements and electrochemical impedance spectroscopy were used to investigate the optimized inhibitory behavior of T3AP using the response surface methodology (RSM), with the optimized result obtained using a temperature of 42.90 °C, acid concentration of 2.38 M, inhibitor concentration of 3.80 mM, and time of 18.97 h, with inhibition efficiency up to approximately 93%. Validation of the experimental and predicted RSM showed that no significant difference in the inhibition efficiency with the confidence level value up to 97% was obtained. The isotherm study shows that T3AP obeys the Langmuir isotherm adsorption model, with physisorption and chemisorption adsorption mechanisms. The effectiveness of inhibitor performance of T3AP can be visually observed using scanning electron microscopy and X-ray photoelectron spectroscopy. The characterization revealed that the reactive S and N atoms in the T3AP inhibitor form strong chemical adsorption through N-Cu and Cu-S bonds on the copper surface. Computational analysis was also carried out, and we found that the stable energy gap between the occupied and unoccupied molecular orbitals (4.6891 eV) and high binding energy (540.962 kJ mol-1) adsorption from molecular dynamics were in agreement with the experimental findings.
  16. K A, Sharma A, Kumar D, Singh SK, Gupta G, Chellappan DK, et al.
    J Med Virol, 2022 Oct;94(10):4628-4643.
    PMID: 35705439 DOI: 10.1002/jmv.27936
    The global pandemic of COVID-19 began in December 2019 and is still continuing. The past 2 years have seen the emergence of several variants that were more vicious than each other. The emergence of Omicron (B.1.1.529) proved to be a huge epidemiological concern as the rate of infection of this particular strain was enormous. The strain was identified in South Africa on November 24, 2021 and was classified as a "Variant of Concern" on November 26, 2021. The Omicron variant possessed mutations in the key RBD region, the S region, thereby increasing the affinity of ACE2 for better transmission of the virus. Antibody resistance was found in this variant and it was able to reduce vaccine efficiency of vaccines. The need for a booster vaccine was brought forth due to the prevalence of the Omicron variant and, subsequently, this led to targeted research and development of variant-specific vaccines and booster dosage. This review discusses broadly the genomic characters and features of Omicron along with its specific mutations, evolution, antibody resistance, and evasion, utilization of CRISPR-Cas12a assay for Omicron detection, T-cell immunity elicited by vaccines against Omicron, and strategies to decrease Omicron infection along with COVID-19 and it also discusses on XE recombinant variant and on infectivity of BA.2 subvariant of Omicron.
    MeSH terms: Humans; Pandemics
  17. Wong LP, Alias H, Seheli FN, Zimet GD, Hu Z, Lin Y
    Hum Vaccin Immunother, 2022 Nov 30;18(5):2076525.
    PMID: 35714272 DOI: 10.1080/21645515.2022.2076525
    INTRODUCTION: This study aimed to investigate HPV vaccination intention among adult married women aged 27 to 45 years and its associated factors, and their spouse/partner's influence on HPV vaccination decision-making.

    METHODS: This is a cross-sectional, questionnaire-based study. Study participants were recruited through simple random sampling of patients attending obstetrics and gynecology outpatient clinics in a university teaching hospital. Participants were selected based on a computer-generated list of a random list of patients attending the clinic.

    RESULTS: A total of 794 complete responses were received (response rate 88.2%). The mean age of the respondents was 32.2 years with a standard deviation (SD) of ±3.9 years.The vast majority (85.3%) would communicate with their spouse/partner with regard to HPV vaccination decision-making. Nearly 30% (over half were of the Malay ethnic group) perceived their spouse/partner would not consent to their HPV vaccination. Over half (54.9%) reported joint decision-making, and 9.1% (the majority of whom were Malay) reported that HPV vaccination was dependent on their spouse/partner's decision. Intention to vaccinate against HPV was high (74.5%). Factors influencing HPV vaccination intention were spouse/partner's consent to HPV vaccination (odds ratio [OR] = 4.51; 95% confidence interval [CI], 3.08-6.62), being a postgraduate student (OR = 4.55; 95% CI, 2.13-9.72 vs. unemployed/housewife), average household income MYR2000-4000 (OR = 2.09; 95%CI, 1.16-3.78 vs. below MYR2000), and an HPV-related knowledge score of 9-20 (OR = 1.60; 95% CI, 1.10-2.32 vs. score 0-8).

    CONCLUSION: Findings highlight the importance of culture-centered interventions to enhance male partner's awareness and support for the HPV vaccination of married women.

    MeSH terms: Adult; Cross-Sectional Studies; Female; Humans; Health Knowledge, Attitudes, Practice; Malaysia; Male; Patient Acceptance of Health Care; Surveys and Questionnaires; Vaccination; Intention; Alphapapillomavirus*; Papillomavirus Vaccines*
  18. Gupta V, Jain N, Sachdeva J, Gupta M, Mohan S, Bajuri MY, et al.
    Multimed Tools Appl, 2022;81(26):37657-37680.
    PMID: 35968409 DOI: 10.1007/s11042-022-13509-4
    The novel coronavirus disease, which originated in Wuhan, developed into a severe public health problem worldwide. Immense stress in the society and health department was advanced due to the multiplying numbers of COVID carriers and deaths. This stress can be lowered by performing a high-speed diagnosis for the disease, which can be a crucial stride for opposing the deadly virus. A good large amount of time is consumed in the diagnosis. Some applications that use medical images like X-Rays or CT-Scans can pace up the time used in diagnosis. Hence, this paper aims to create a computer-aided-design system that will use the chest X-Ray as input and further classify it into one of the three classes, namely COVID-19, viral Pneumonia, and healthy. Since the COVID-19 positive chest X-Rays dataset was low, we have exploited four pre-trained deep neural networks (DNNs) to find the best for this system. The dataset consisted of 2905 images with 219 COVID-19 cases, 1341 healthy cases, and 1345 viral pneumonia cases. Out of these images, the models were evaluated on 30 images of each class for the testing, while the rest of them were used for training. It is observed that AlexNet attained an accuracy of 97.6% with an average precision, recall, and F1 score of 0.98, 0.97, and 0.98, respectively.
  19. Lozano AI, García-Abenza A, Blanco Ramos F, Hasan M, Slaughter DS, Weber T, et al.
    J Phys Chem A, 2022 Sep 15;126(36):6032-6046.
    PMID: 36069053 DOI: 10.1021/acs.jpca.2c05005
    In this Review, we present a comparative study between electron and positron scattering cross sections from CO2 molecules over a broad impact energy range (0.1-5000 eV). For electron scattering, new total electron scattering cross sections (e-TCS) have been measured with a high resolution magnetically confined electron beam transmission system from 1 to 200 eV. Dissociative electron attachment processes for electron energies from 3 to 52 eV have been analyzed by measuring the relative O- anion production yield. In addition, elastic, inelastic, and total scattering cross section calculations have been carried out in the framework of the Independent Atom Model by using the Screening Corrected Additive Rule, including interference effects (IAM-SCARI). Based on the previous cross section compilation from Itikawa ( J. Phys. Chem. Ref. Data, 2002, 31, 749-767) and the present measurements and calculations, an updated recommended e-TCS data set has been used as reference values to obtain a self-consistent integral cross section data set for the elastic and inelastic (vibrational excitation, electronic excitation, and ionization) scattering channels. A similar calculation has been carried out for positrons, which shows important differences between the electron scattering behavior: e.g., more relevance of the target polarization at the lower energies, more efficient excitation of the target at intermediate energies, but a lower total scattering cross section for increasing energies, even at 5000 eV. This result does not agree with the charge independence of the scattering cross section predicted by the first Born approximation (FBA). However, we have shown that the inelastic channels follow the FBA's predictions for energies above 500 eV while the elastic part, due to the different signs of the scattering potential constituent terms, remains lower for positrons even at the maximum impact energy considered here (5000 eV). As in the case of electrons, a self-consistent set of integral positron scattering cross sections, including elastic and inelastic (vibrational excitation, electronic excitation, positronium formation, and ionization) channels is provided. Again, to derive these data, positron scattering total cross sections based on a previous compilation from Brunger et al. ( J. Phys. Chem. Ref. Data, 2017, 46, 023102) and the present calculation have been used as reference values. Data for the main inelastic channels, i.e. direct ionization and positronium formation, derived with this procedure, show excellent agreement with the experimental results available in the literature. Inconsistencies found between different model potential calculations, both for the elastic and inelastic collision processes, suggest that new calculations using more sophisticated methods are required.
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