Performance of Sustainable Green Concrete Incorporating Quarry Dust and Ferronickel Slag as Fine Aggregate.

This paper presents a study on the combined use of two by-products, namely quarry dust (QD) and ferronickel slag (FNS), as a full substitute for natural sand to improve the greenness of concrete production. Quarry dust was used in increments of 25% to a maximum of 75% substitution, where nickel slag was used as the remaining proportion of fine aggregate. All the combinations of quarry dust and nickel slag were found to be compliant with AS 2758.1 and they showed notably better grading than 100% sand. In this research, standard concrete tests, such as the slump test for fresh concrete, and compression, tensile and shrinkage tests for hardened concrete, were conducted. Scanning electron microscopy and X-ray diffraction analysis were also conducted for microstructural investigation. The results concluded that the combinations of quarry dust and nickel slag in concrete as a whole substitution of sand provide similar results for these properties. Specifically, 25% quarry dust with 75% nickel slag proved to be the most promising alternative to sand, with compressive and splitting tensile strengths of 62 and 4.29 MPa, respectively, which were 16% and 20% higher than those of the control mix. Also, lower drying shrinkage was observed for this combination compared to the control mix. The higher strength is attributed to the rough texture and angular shape of both quarry dust and nickel slag providing a better mechanical interlocking. The validity of this result has also been confirmed through image analysis of micrographs from various specimens. In microstructural investigations, specimens with QD and FNS exhibited fewer voids and a more compact surface compared to the control specimen. This shows the potential for further research into the use of quarry dust and nickel slag in the production of green concrete.

Acute disseminated encephalomyelitis following the COVID-19 Vaccine Sinopharm in low- and middle-income country: a case report.

Introduction and importance: Coronavirus disease 2019 (COVID-19) is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and various vaccines against it have been developed. Acute disseminated encephalomyelitis (ADEM) is a disease of the central nervous system that cause inflammation and demyelination and manifests as a multi-symptom acute neurological condition. Although infections are usually the cause of ADEM, vaccines may cause 5-10% of cases. Case presentation: A 40-year-old woman had received a second dose of the Sinopharm COVID-19 vaccine 4 months before her visit and experienced sudden gait imbalance and vertigo a day after her vaccination, which lasted for more than a month. On examination, no signs of skin bruising or bleeding were observed, and her vital signs were within the normal range. On neurological assessment, the patient had a Glasgow Coma Scale score of 14/15 (E4V5M5), had normal pupil size and light reaction, normal fundus, normal deep tendon reflexes and bilateral extensor plantar response. Meningeal symptoms were absent, and SARS-CoV-2 RNA tests using NAAT (Nucleic Acid Amplification Test) were negative. Development of central nervous system (CNS) manifestations during the recovery phase of fever, along with typical MRI findings; the diagnosis of para-infectious ADEM with COVID-19 vaccination was made. After the treatment with methylprednisolone sodium succinate injection, the patient showed improvement. Clinical discussion: ADEM associated with post-vaccinations is a rare condition. There has been growing evidence that shared epitopes between neuronal proteins and SARS-CoV-2 antigens may trigger autoimmune reactions against the CNS through molecular mimicry as its pathogenesis. Conclusion: We suggest the need for a strict vaccine safety monitoring system and post-vaccine monitoring and surveillance.

Quantitative trait locus (QTL) analysis and fine-mapping for Fusarium oxysporum disease resistance in Raphanus sativus using GRAS-Di technology.

Fusarium wilt is a significant disease in radish, but the genetic mechanisms controlling yellows resistance (YR) are not well understood. This study aimed to identify YR-QTLs and to fine-map one of them using F2:3 populations developed from resistant and susceptible radish parents. In this study, two high-density genetic maps each containing shared co-dominant markers and either female or male dominant markers that spanned 988.6 and 1127.5 cM with average marker densities of 1.40 and 1.53 cM, respectively, were generated using Genotyping by Random Amplicon Sequencing-Direct (GRAS-Di) technology. We identified two YR-QTLs on chromosome R2 and R7, and designated the latter as ForRs1 as the major QTL. Fine mapping narrowed down the ForRs1 locus to a 195 kb region. Among the 16 predicted genes in the delimited region, 4 genes including two receptor-like protein and -kinase genes (RLP/RLK) were identified as prime candidates for ForRs1 based on the nucleotide sequence comparisons between the parents and their predicted functions. This study is the first to use a GRAS-Di for genetic map construction of cruciferous crops and fine map the YR-QTL on the R7 chromosome of radish. These findings will provide groundbreaking insights into radish YR breeding and understanding the genetics of YR mechanism.