Displaying publications 1 - 20 of 33 in total

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  1. Altharan YM, Shamsudin S, Lajis MA, Al-Alimi S, Yusuf NK, Alduais NAM, et al.
    PLoS One, 2024;19(3):e0300504.
    PMID: 38484005 DOI: 10.1371/journal.pone.0300504
    Direct recycling of aluminum waste is crucial in sustainable manufacturing to mitigate environmental impact and conserve resources. This work was carried out to study the application of hot press forging (HPF) in recycling AA6061 aluminum chip waste, aiming to optimize operating factors using Response Surface Methodology (RSM), Artificial Neural Network (ANN) and Genetic algorithm (GA) strategy to maximize the strength of recycled parts. The experimental runs were designed using Full factorial and RSM via Minitab 21 software. RSM-ANN models were employed to examine the effect of factors and their interactions on response and to predict output, while GA-RSM and GA-ANN were used for optimization. The chips of different morphology were cold compressed into billet form and then hot forged. The effect of varying forging temperature (Tp, 450-550°C), holding time (HT, 60-120 minutes), and chip surface area to volume ratio (AS:V, 15.4-52.6 mm2/mm3) on ultimate tensile strength (UTS) was examined. Maximum UTS (237.4 MPa) was achieved at 550°C, 120 minutes and 15.4 mm2/mm3 of chip's AS: V. The Tp had the largest contributing effect ratio on the UTS, followed by HT and AS:V according to ANOVA analysis. The proposed optimization process suggested 550°C, 60 minutes, and 15.4 mm2 as the optimal condition yielding the maximum UTS. The developed models' evaluation results showed that ANN (with MSE = 1.48%) outperformed RSM model. Overall, the study promotes sustainable production by demonstrating the potential of integrating RSM and ML to optimize complex manufacturing processes and improve product quality.
  2. Chen G, Zhou W, Guan D, Sunarso J, Zhu Y, Hu X, et al.
    Sci Adv, 2017 06;3(6):e1603206.
    PMID: 28691090 DOI: 10.1126/sciadv.1603206
    Perovskite oxides exhibit potential for use as electrocatalysts in the oxygen evolution reaction (OER). However, their low specific surface area is the main obstacle to realizing a high mass-specific activity that is required to be competitive against the state-of-the-art precious metal-based catalysts. We report the enhanced performance of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) for the OER with intrinsic activity that is significantly higher than that of the benchmark IrO2, and this result was achieved via fabrication of an amorphous BSCF nanofilm on a surface-oxidized nickel substrate by magnetron sputtering. The surface nickel oxide layer of the Ni substrate and the thickness of the BSCF film were further used to tune the intrinsic OER activity and stability of the BSCF catalyst by optimizing the electronic configuration of the transition metal cations in BSCF via the interaction between the nanofilm and the surface nickel oxide, which enables up to 315-fold enhanced mass-specific activity compared to the crystalline BSCF bulk phase. Moreover, the amorphous BSCF-Ni foam anode coupled with the Pt-Ni foam cathode demonstrated an attractive small overpotential of 0.34 V at 10 mA cm-2 for water electrolysis, with a BSCF loading as low as 154.8 μg cm-2.
  3. Cheong MW, Chong ZS, Liu SQ, Zhou W, Curran P, Bin Yu
    Food Chem, 2012 Sep 15;134(2):686-95.
    PMID: 23107679 DOI: 10.1016/j.foodchem.2012.02.162
    Volatile compounds in the peel of calamansi (Citrus microcarpa) from Malaysia, the Philippines and Vietnam were extracted with dichloromethane and hexane, and then analysed by gas chromatography-mass spectroscopy/flame ionisation detector. Seventy-nine compounds representing >98% of the volatiles were identified. Across the three geographical sources, a relatively small proportion of potent oxygenated compounds was significantly different, exemplified by the highest amount of methyl N-methylanthranilate in Malaysian calamansi peel. Principal component analysis and canonical discriminant analysis were applied to interpret the complex volatile compounds in the calamansi peel extracts, and to verify the discrimination among the different origins. In addition, four common hydroxycinnamic acids (caffeic, p-coumaric, ferulic and sinapic acids) were determined in the methanolic extracts of calamansi peel using ultra-fast liquid chromatography coupled to photodiode array detector. The Philippines calamansi peel contained the highest amount of total phenolic acids. In addition, p-Coumaric acid was the dominant free phenolic acids, whereas ferulic acid was the main bound phenolic acid.
  4. Cheong MW, Zhu D, Sng J, Liu SQ, Zhou W, Curran P, et al.
    Food Chem, 2012 Sep 15;134(2):696-703.
    PMID: 23107680 DOI: 10.1016/j.foodchem.2012.02.139
    Calamansi juices from three countries (Malaysia, the Philippines and Vietnam) were characterised through measuring volatiles, physicochemical properties and non-volatiles (sugars, organic acids and phenolic acids). The volatile components of manually squeezed calamansi juices were extracted using dichloromethane and headspace solid-phase microextraction, and then analysed using gas chromatography-mass spectrometry/flame ionisation detector, respectively. A total of 60 volatile compounds were identified. The results indicated that the Vietnam calamansi juice contained the highest amount of volatiles. Two principal components obtained from principal component analysis (PCA) represented 89.65% of the cumulative total variations of the volatiles. Among the non-volatile components, these three calamansi juices could be, to some extent, differentiated according to fructose and glucose concentrations. Hence, this study of calamansi juices could lead to a better understanding of calamansi fruits.
  5. He J, Sunarso J, Miao J, Sun H, Dai J, Zhang C, et al.
    J Hazard Mater, 2019 05 05;369:699-706.
    PMID: 30831522 DOI: 10.1016/j.jhazmat.2019.02.070
    Effective regulation of p-phenylenediamine (PPD), a widely used precursor of hair dye that is harmful to human health in large concentration, relies upon an accurate yet simple detection of PPD. In this context, amperometric electrode sensor based on perovskite oxide becomes attractive given its portability, low cost, high sensitivity, and rapid processing time. This work reports the systematic characterization of a series of Sr-doped PrCoO3-δ perovskite oxides with composition of Pr1-xSrxCoO3-δ(x = 0, 0.2, 0.4, 0.6, 0.8, and 1) for PPD detection in an alkaline solution. PSC82 deposited onto glassy carbon electrode (PSC82/GCE) generates the highest redox currents which correlates with the highest hydrogen peroxide intermediates (HO2-) yield and the σ*-orbital (eg) filling of Co that is closest to unity for PSC82. PSC82/GCE provides the highest sensitivities of 655 and 308 μA mM-1 cm-2 in PPD concentration range of 0.5-2,900 and 2,900-10,400 μM, respectively, with a limit of detection of 0.17 μM. PSC82/GCE additionally demonstrates high selectivity to PPD and long term stability during 50 consecutive cyclic voltammetry scans and over 1-month storage period. The potential applicability of PSC82/GCE was also demonstrated by confirming the presence of very low concentration of PPD of below 0.5% in real hair dyes.
  6. Hu T, Qiu W, He B, Zhang Y, Yu J, Liang X, et al.
    BMC Microbiol, 2014;14:293.
    PMID: 25433675 DOI: 10.1186/s12866-014-0293-4
    In recent years novel human respiratory disease agents have been described for Southeast Asia and Australia. The causative pathogens were classified as pteropine orthoreoviruses with a strong phylogenetic relationship to orthoreoviruses of bat origin.
  7. Hu T, Zheng Y, Zhang Y, Li G, Qiu W, Yu J, et al.
    BMC Microbiol, 2012;12:305.
    PMID: 23268691 DOI: 10.1186/1471-2180-12-305
    The identification of new virus strains is important for the study of infectious disease, but current (or existing) molecular biology methods are limited since the target sequence must be known to design genome-specific PCR primers. Thus, we developed a new method for the discovery of unknown viruses based on the cDNA--random amplified polymorphic DNA (cDNA-RAPD) technique. Getah virus, belonging to the family Togaviridae in the genus Alphavirus, is a mosquito-borne enveloped RNA virus that was identified using the Virus-Discovery-cDNA RAPD (VIDISCR) method.
  8. Jani P, Mishra U, Buchmayer J, Walker K, Gözen D, Maheshwari R, et al.
    Pediatr Res, 2023 May;93(6):1701-1709.
    PMID: 36075989 DOI: 10.1038/s41390-022-02297-0
    BACKGROUND: Are thermoregulation and golden hour practices in extremely preterm (EP) infants comparable across the world? This study aims to describe these practices for EP infants based on the neonatal intensive care unit's (NICUs) geographic region, country's income status and the lowest gestational age (GA) of infants resuscitated.

    METHODS: The Director of each NICU was requested to complete the e-questionnaire between February 2019 and August 2021.

    RESULTS: We received 848 responses, from all geographic regions and resource settings. Variations in most thermoregulation and golden hour practices were observed. Using a polyethylene plastic wrap, commencing humidity within 60 min of admission, and having local protocols were the most consistent practices (>75%). The odds for the following practices differed in NICUs resuscitating infants from 22 to 23 weeks GA compared to those resuscitating from 24 to 25 weeks: respiratory support during resuscitation and transport, use of polyethylene plastic wrap and servo-control mode, commencing ambient humidity >80% and presence of local protocols.

    CONCLUSION: Evidence-based practices on thermoregulation and golden hour stabilisation differed based on the unit's region, country's income status and the lowest GA of infants resuscitated. Future efforts should address reducing variation in practice and aligning practices with international guidelines.

    IMPACT: A wide variation in thermoregulation and golden hour practices exists depending on the income status, geographic region and lowest gestation age of infants resuscitated. Using a polyethylene plastic wrap, commencing humidity within 60 min of admission and having local protocols were the most consistent practices. This study provides a comprehensive description of thermoregulation and golden hour practices to allow a global comparison in the delivery of best evidence-based practice. The findings of this survey highlight a need for reducing variation in practice and aligning practices with international guidelines for a comparable health care delivery.

  9. Li B, He Z, Peters R, Allender S, Zou Y, Zhou W, et al.
    Int J Behav Nutr Phys Act, 2023 Sep 18;20(1):111.
    PMID: 37723534 DOI: 10.1186/s12966-023-01510-5
    BACKGROUND: Group Model Building (GMB) is a participatory system dynamics method increasingly used to address complex public health issues like obesity. GMB represents a set of well-defined steps to engage key stakeholders to identify shared drivers and solutions of a given problem. However, GMB has not yet been applied specifically to develop multi-duty interventions that address multiple inter-related issues such as malnutrition in all its forms (MIAIF). Moreover, a recent systematic review of empirical applications of a systems approach to developing obesity interventions found no published work from non-western, low- and middle-income countries (LMICs). In this paper we describe adaptations and innovations to a common GMB process to co-develop systemic MIAIF interventions with Chinese decision-makers.

    METHODS: We developed, piloted and implemented multiple cultural adaptations and two methodological innovations to the commonly used GMB process in Fang Cheng Gang city, China. We included formal, ceremonial and policy maker engagement events before and between GMB workshops, and incorporated culturally tailored arrangements during participant recruitment (officials of the same seniority level joined the same workshop) and workshop activities (e.g., use of individual scoring activities and hand boards). We made changes to the commonly used GMB activities which enabled mapping of shared drivers of multiple health issues (in our case MIAIF) in a single causal loop diagram. We developed and used a 'hybrid' GMB format combining online and in person facilitation to reduce travel and associated climate impact.

    RESULTS: Our innovative GMB process led to high engagement and support from decision-makers representing diverse governmental departments across the whole food systems. We co-identified and prioritised systemic drivers and intervention themes of MIAIF. The city government established an official Local Action Group for long-term, inter-departmental implementation, monitoring and evaluation of the co-developed interventions. The 'hybrid' GMB format enabled great interactions while reducing international travel and mitigating limitations of fully online GMB process.

    CONCLUSIONS: Cultural and methodological adaptations to the common GMB process for an Asian LMIC setting were successful. The 'hybrid' GMB format is feasible, cost-effective, and more environmentally friendly. These cultural adaptations could be considered for other Asian settings and beyond to address inter-related, complex issues such as MIAIF.

  10. Li JH, Vicknasingam B, Cheung YW, Zhou W, Nurhidayat AW, Jarlais DC, et al.
    Subst Abuse Rehabil, 2011;2:11-20.
    PMID: 24474851 DOI: 10.2147/SAR.S15458
    Ketamine, a derivative of phencyclidine that was developed in the 1960s, is an anesthetic and analgesic with hallucinogenic effects. In this paper, the pharmacological and toxicological effects of ketamine are briefly reviewed. Ketamine possesses a wide safety margin but such a therapeutic benefit is somewhat offset by its emergence phenomenon (mind-body dissociation and delirium) and hallucinogenic effects. The increasing abuse of ketamine, initially predominantly in recreational scenes to experience a "k-hole" and other hallucinatory effects but more recently also as a drug abused during the workday or at home, has further pushed governments to confine its usage in many countries. Recently, urinary tract dysfunction has been associated with long-term ketamine use. In some long-term ketamine users, such damage can be irreversible and could result in renal failure and dialysis. Although ketamine has not yet been scheduled in the United Nations Conventions, previous studies using different assessment parameters to score the overall harms of drugs indicated that ketamine may cause more harm than some of the United Nations scheduled drugs. Some countries in Southeast and East Asia have reported an escalating situation of ketamine abuse. Dependence, lower urinary tract dysfunction, and sexual impulse or violence were the most notable among the ketamine-associated symptoms in these countries. These results implied that the danger of ketamine may have been underestimated previously. Therefore, the severity levels of the ketamine-associated problems should be scrutinized more carefully and objectively. To prevent ketamine from being improperly used and evolving into an epidemic, a thorough survey on the prevalence and characteristics of illicit ketamine use is imperative so that suitable policy and measures can be taken. On the other hand, recent findings that ketamine could be useful for treating major depressive disorder has given this old drug a new impetus. If ketamine is indeed a remedy for treating depression, more research on the risks and benefits of its clinical use will be indispensable.
  11. Lin XF, Wong SY, Zhou W, Shen W, Li W, Tsai CC
    Int J Sci Math Educ, 2023 May 04.
    PMID: 37363784 DOI: 10.1007/s10763-023-10376-9
    Research evidence indicated that a specific type of augmented reality-assisted (AR-assisted) science learning design or support might not suit or be effective for all students because students' cognitive load might differ according to their experiences and individual characteristics. Thus, this study aimed to identify undergraduate students' profiles of cognitive load in AR-assisted science learning and to examine the role of their distinct profiles in self-efficacy together with associated behavior patterns in science learning. After ensuring the validity and reliability of each measure, a latent profile analysis confirmed that 365 Chinese undergraduates carried diverse dimensions of cognitive load simultaneously. The latent profile analysis findings revealed four fundamental profiles: Low Engagement, Immersive, Dabbling, and Organized, characterized as carrying various respective cognitive loads. The multivariate analysis of variance findings revealed different levels of the six AR science learning self-efficacy dimensions across profiles. Low Engagement students displayed the lowest self-efficacy among all dimensions. Organized students recorded better conceptual understanding and higher-order cognitive skills than Dabbling ones. Students with the Immersive profile had the highest science learning self-efficacy. The lag sequential analysis results showed significant differences in behavior patterns among profiles. Among them, profiles with social interaction, test, and reviewing feedback behavior had a significantly higher score for self-efficacy than those patterns mainly based on test learning and resource visits. This finding provides a unified consideration of students' diverse profiles and can inform interventions for effective design of AR-assisted science learning to match appropriate strategies to facilitate the science learning effect.
  12. Machiela MJ, Zhou W, Karlins E, Sampson JN, Freedman ND, Yang Q, et al.
    Nat Commun, 2016 06 13;7:11843.
    PMID: 27291797 DOI: 10.1038/ncomms11843
    To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events >2 Mb in 97 (0.25%) women. Here we show rates for X-chromosome mosaicism are four times higher than mean autosomal rates; X mosaic events more often include the entire chromosome and participants with X events more likely harbour autosomal mosaic events. X mosaicism frequency increases with age (0.11% in 50-year olds; 0.45% in 75-year olds), as reported for Y and autosomes. Methylation array analyses of 33 women with X mosaicism indicate events preferentially involve the inactive X chromosome. Our results provide further evidence that the sex chromosomes undergo mosaic events more frequently than autosomes, which could have implications for understanding the underlying mechanisms of mosaic events and their possible contribution to risk for chronic diseases.
  13. Miao J, Sunarso J, Duan X, Zhou W, Wang S, Shao Z
    J Hazard Mater, 2018 May 05;349:177-185.
    PMID: 29425884 DOI: 10.1016/j.jhazmat.2018.01.054
    The efficient oxidative removal of persistent organic components in wastewater relies on low-cost heterogeneous catalysts that offer high catalytic activity, stability, and recyclability. Here, we designed a series of nanostructured Co-Mn containing perovskite catalysts, LaCo1-xMnxO3+δ (LCM, x = 0, 0.3, 0.5, 0.7, and 1.0), with over-stoichiometric oxygen (δ > 0) to show superior catalytic activity for the degradation of a variety of persistent aqueous organic pollutants by activating peroxymonosulfate (PMS). The nature of LCM for catalysis was comprehensively investigated. A "volcano-shaped" correlation was observed between the catalytic activity and electron filling (eg) of Co in LCM. Among these compounds, LaCo0.5Mn0.5O3+δ (LCM55) exhibited an excellent activity with eg = 1.27. The high interstitial oxygen ion diffusion rate (DO2- = 1.58 ± 0.01 × 10-13 cm2 s-1) of LCM55 also contributes to its catalytic activity. The enhanced stability of LCM55 can be ascribed to its stronger relative acidity (3.22). Moreover, an increased solution pH (pH ≥ 7) generated a faster organic degradation rate and a decrease in metal leaching (0.004 mM) for LCM55 perovskite, justifying it as a potential material for environmental remediation.
  14. Miao J, Sunarso J, Su C, Zhou W, Wang S, Shao Z
    Sci Rep, 2017 03 10;7:44215.
    PMID: 28281656 DOI: 10.1038/srep44215
    Perovskite-like oxides SrCo1-xTixO3-δ (SCTx, x = 0.1, 0.2, 0.4, 0.6) were used as heterogeneous catalysts to activate peroxymonosulfate (PMS) for phenol degradation under a wide pH range, exhibiting more rapid phenol oxidation than Co3O4 and TiO2. The SCT0.4/PMS system produced a high activity at increased initial pH, achieving optimized performance at pH ≥ 7 in terms of total organic carbon removal, the minimum Co leaching and good catalytic stability. Kinetic studies showed that the phenol oxidation kinetics on SCT0.4/PMS system followed the pseudo-zero order kinetics and the rate on SCT0.4/PMS system decreased with increasing initial phenol concentration, decreased PMS amount, catalyst loading and solution temperature. Quenching tests using ethanol and tert-butyl alcohol demonstrated sulfate and hydroxyl radicals for phenol oxidation. This investigation suggested promising heterogeneous catalysts for organic oxidation with PMS, showing a breakthrough in the barriers of metal leaching, acidic pH, and low efficiency of heterogeneous catalysis.
  15. Pagliuca S, Gurnari C, Hercus C, Hergalant S, Nadarajah N, Wahida A, et al.
    Leukemia, 2023 Jan;37(1):202-211.
    PMID: 36253429 DOI: 10.1038/s41375-022-01723-w
    Idiopathic aplastic anemia (IAA) pathophysiology is dominated by autoreactivity of human leukocyte antigen (HLA)-restricted T-cells against antigens presented by hematopoietic stem and progenitor cells (HSPCs). Expansion of PIGA and HLA class I mutant HSPCs have been linked to immune evasion from T-cell mediated pressures. We hypothesized that in analogy with antitumor immunity, the pathophysiological cascade of immune escape in IAA is initiated by immunoediting pressures and culminates with mechanisms of clonal evolution characterized by hits in immune recognition and response genes. To that end, we studied the genetic and transcriptomic make-up of the antigen presentation complexes in a large cohort of patients with IAA and paroxysmal nocturnal hemoglobinuria (PNH) by using single-cell RNA, high throughput DNA sequencing and single nucleotide polymorphism (SNP)-array platforms. At disease onset, HSPCs displayed activation of selected HLA class I and II-restricted mechanisms, without extensive inhibition of immune checkpoint apparatus. Using a newly implemented bioinformatic framework we found that not only class I but also class II genes were often impaired by acquisition of genetic aberrations. We also demonstrated the presence of novel somatic alterations in immune genes possibly contributing to the evasion from the autoimmune T-cells. In contrast, these hits were absent in myeloid neoplasia. These aberrations were not mutually exclusive with PNH and did not correlate with the accumulation of myeloid-driver hits. Our findings shed light on the mechanisms of immune activation and escape in IAA and define alternative modes of clonal hematopoiesis.
  16. Peters R, Li B, Swinburn B, Allender S, He Z, Lim SY, et al.
    Bull World Health Organ, 2023 Nov 01;101(11):690-706F.
    PMID: 37961057 DOI: 10.2471/BLT.23.289973
    OBJECTIVE: To identify and analyse ongoing nutrition-related surveillance programmes led and/or funded by national authorities in countries in South-East Asian and Western Pacific Regions.

    METHODS: We systematically searched for publications in PubMed® and Scopus, manually searched the grey literature and consulted with national health and nutrition officials, with no restrictions on publication type or language. We included low- and middle-income countries in the World Health Organization South-East Asia Region, and the Association of Southeast Asian Nations and China. We analysed the included programmes by adapting the United States Centers for Disease Control and Prevention's public health surveillance evaluation framework.

    FINDINGS: We identified 82 surveillance programmes in 18 countries that repeatedly collect, analyse and disseminate data on nutrition and/or related indicators. Seventeen countries implemented a national periodic survey that exclusively collects nutrition-outcome indicators, often alongside internationally linked survey programmes. Coverage of different subpopulations and monitoring frequency vary substantially across countries. We found limited integration of food environment and wider food system indicators in these programmes, and no programmes specifically monitor nutrition-sensitive data across the food system. There is also limited nutrition-related surveillance of people living in urban deprived areas. Most surveillance programmes are digitized, use measures to ensure high data quality and report evidence of flexibility; however, many are inconsistently implemented and rely on external agencies' financial support.

    CONCLUSION: Efforts to improve the time efficiency, scope and stability of national nutrition surveillance, and integration with other sectoral data, should be encouraged and supported to allow systemic monitoring and evaluation of malnutrition interventions in these countries.

  17. Pfister NT, Fomin V, Regunath K, Zhou JY, Zhou W, Silwal-Pandit L, et al.
    Genes Dev., 2015 Jun 15;29(12):1298-315.
    PMID: 26080815 DOI: 10.1101/gad.263202.115
    Mutant p53 impacts the expression of numerous genes at the level of transcription to mediate oncogenesis. We identified vascular endothelial growth factor receptor 2 (VEGFR2), the primary functional VEGF receptor that mediates endothelial cell vascularization, as a mutant p53 transcriptional target in multiple breast cancer cell lines. Up-regulation of VEGFR2 mediates the role of mutant p53 in increasing cellular growth in two-dimensional (2D) and three-dimensional (3D) culture conditions. Mutant p53 binds near the VEGFR2 promoter transcriptional start site and plays a role in maintaining an open conformation at that location. Relatedly, mutant p53 interacts with the SWI/SNF complex, which is required for remodeling the VEGFR2 promoter. By both querying individual genes regulated by mutant p53 and performing RNA sequencing, the results indicate that >40% of all mutant p53-regulated gene expression is mediated by SWI/SNF. We surmise that mutant p53 impacts transcription of VEGFR2 as well as myriad other genes by promoter remodeling through interaction with and likely regulation of the SWI/SNF chromatin remodeling complex. Therefore, not only might mutant p53-expressing tumors be susceptible to anti VEGF therapies, impacting SWI/SNF tumor suppressor function in mutant p53 tumors may also have therapeutic potential.
  18. Shang X, Peng Z, Ye Y, Asan, Zhang X, Chen Y, et al.
    EBioMedicine, 2017 Sep;23:150-159.
    PMID: 28865746 DOI: 10.1016/j.ebiom.2017.08.015
    Hemoglobinopathies are among the most common autosomal-recessive disorders worldwide. A comprehensive next-generation sequencing (NGS) test would greatly facilitate screening and diagnosis of these disorders. An NGS panel targeting the coding regions of hemoglobin genes and four modifier genes was designed. We validated the assay by using 2522 subjects affected with hemoglobinopathies and applied it to carrier testing in a cohort of 10,111 couples who were also screened through traditional methods. In the clinical genotyping analysis of 1182 β-thalassemia subjects, we identified a group of additional variants that can be used for accurate diagnosis. In the molecular screening analysis of the 10,111 couples, we detected 4180 individuals in total who carried 4840 mutant alleles, and identified 186 couples at risk of having affected offspring. 12.1% of the pathogenic or likely pathogenic variants identified by our NGS assay, which were undetectable by traditional methods. Compared with the traditional methods, our assay identified an additional at-risk 35 couples. We describe a comprehensive NGS-based test that offers advantages over the traditional screening/molecular testing methods. To our knowledge, this is among the first large-scale population study to systematically evaluate the application of an NGS technique in carrier screening and molecular diagnosis of hemoglobinopathies.
  19. She S, Yu J, Tang W, Zhu Y, Chen Y, Sunarso J, et al.
    ACS Appl Mater Interfaces, 2018 Apr 11;10(14):11715-11721.
    PMID: 29546981 DOI: 10.1021/acsami.8b00682
    Perovskite oxide is an attractive low-cost alternative catalyst for oxygen evolution reaction (OER) relative to the precious metal oxide-based electrocatalysts (IrO2 and RuO2). In this work, a series of Sr-doped La-based perovskite oxide catalysts with compositions of La1- xSr xFeO3-δ ( x = 0, 0.2, 0.5, 0.8, and 1) are synthesized and characterized. The OER-specific activities in alkaline solution increase in the order of LaFeO3-δ (LF), La0.8Sr0.2FeO3-δ (LSF-0.2), La0.5Sr0.5FeO3-δ (LSF-0.5), SrFeO3-δ (SF), and La0.2Sr0.8FeO3-δ (LSF-0.8). We establish a direct correlation between the enhancement in the specific activity and the amount of surface oxygen vacancies as well as the surface Fe oxidation states. The improved specific activity for LSF-0.8 is clearly linked to the optimum amount of surface oxygen vacancies and surface Fe oxidation states. We also find that the OER performance stability is a function of the crystal structure and the deviation in the surface La and/or Sr composition(s) from their bulk stoichiometric compositions. The cubic structure and lower deviation, as is the case for LSF-0.8, led to a higher OER performance stability. These surface performance relations provide a promising guideline for constructing efficient water oxidation.
  20. Shen Y, Zhu Y, Sunarso J, Guan D, Liu B, Liu H, et al.
    Chemistry, 2018 May 11;24(27):6950-6957.
    PMID: 29411451 DOI: 10.1002/chem.201705675
    Because of their structural and compositional flexibility, perovskite oxides represent an attractive alternative electrocatalyst class to precious metals for the oxygen reduction reaction (ORR); an important reaction in fuel cells and metal-air batteries. Partial replacement of the original metal cation with another cation, namely, doping, can be used to tailor the ORR activity of perovskite, for which a metal has been exclusively used as the dopant component in the past. Herein, phosphorus is proposed as a non-metal dopant for the cation site to develop a new perovskite family with the formula of La0.8 Sr0.2 Mn1-x Px O3-δ (x=0, 0.02, 0.05, and 0.1; denoted as LSM, LSMP0.02, LSMP0.05, and LSMP0.1, respectively). Powder XRD patterns reveal that the solubility of phosphorus in the perovskite structure is around 0.05. Rotating ring-disk electrode experiments in the form of linear-sweep voltammetry scans demonstrated the best ORR performance for LSMP0.05, and also revealed close to a four-electron ORR pathway for all four compositions. A chronoamperometric test (9000 s) and 500 cycle accelerated durability test demonstrated higher durability for LSMP0.05 relative to that of LSM and the commercial 20 wt % Pt/C catalyst. The higher ORR activity for LSMP0.05 is attributed to the optimised average valence of Mn, as evidenced by combined X-ray photoelectron spectroscopy and soft X-ray absorption spectroscopy data. Doping phosphorus into perovskites is an effective way to develop high-performance electrocatalysts for ORR.
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