558 research outputs found

    Reviews on the Properties of Aggregates made with or without Geopolymerisation Method

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    Aggregates are popular for use in concrete and lightweight concrete applications. Recent research shows that the by-product materials such as fly ash can be used as raw material in producing aggregates and lightweight aggregates. The usage of this material can improve the quality of the aggregates produced compared to conventional in term of structurally strong, physically stable, durable, and environmentally inert. This paper summarized the process and mechanical testing on the fly ash aggregates and lightweight aggregates to be used in concrete

    Infantile acute megakaryoblastic leukaemia with T(1:22) in a non-down syndrome child.

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    Megakaryoblastic leukaemia is the commonest form of leukaemia occuring in Down syndrome infants. However, it’s subtype with translocation t(1;22)(p13;q13)is uncommon comprising <1% of all cases and reported to exclusively occur in infant without Down syndrome. It has a female predominance and carries apoor prognosis. We described this rare form of leukaemia in a 9-month-old girl who presented with bruises, massive hepatosplenomegaly and multiple cervical and inguinal lymphadenopathy. The blood film showed severe anaemia with ovalostomatocytosis, thrombocytopenia and mild leucocytosis. The bone marrow aspirate showed numerous blasts showing high nuclear-cytoplasmic ratio and agranular cytoplasm with cytoplasmic blebs. Peroxidase staining was negative. The immunophenotyping of the blasts showed positive expression of CD117, CD13, CD33 and CD61 which confirmed the diagnosis of acute megakaryoblastic leukaemia. Interestingly, the cytogenetic finding of translocation t(1;22) which is most common in acute megaloblastic leukaemia in infants without Down syndrome was found in this case. She received the AML trial 15 ADE protocol chemotherapy regime and developed severe neutropenic sepsis and respiratory distress requiring ventilatory support and granulocyte colony stimulating factor (G-CSF). She recovered wellmafter the first course of chemotherapy and was discharged. Unfortunately, she was not brought in for follow-up chemotherapy and presented a few months later with relapsed AML. She was re-started on ADE protocol and currently is on oral thioguanine for maintenance therapy

    Squamous cell carcinoma of the tongue in a patient with rothmund-thomson syndrome (Recq4 Mutation) - intolerance to radiotherapy

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    We report a case of squamous cell carcinoma of the base of the tongue in a 27 years old patient with Rothmund-Thomson syndrome (RTS). An abnormal DNA repair mechanism in some RTS patients predispose them to malignancy and influence the tolerance to radiotherapy

    Fly Ash as a Cementitious Material for Concrete

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    This paper presents a review on fly ash as prime materials used for geopolymer. Due to its advantages of abundant resources, less in cost, great workability and high physical properties, fly ash leads to achieving high mechanical properties. Fly ash is considered as one of the largest generated industrial solid wastes or so-called industrial by-products, around the world particularly in China, India, and USA. The characteristics of fly ash allow it to be a geotechnical material to produce geopolymer cement or concrete as an alternative of ordinary Portland cement. Many efforts are made in this direction to formulate a suitable mix design of fly ash-based geopolymer by focusing on fly ash as the main prime material. The physical properties, chemical compositions, and chemical activation of fly ash are analyzed and evaluated in this review paper. Reference has been made to different ASTM, ACI standards, and other researches work in geopolymer area

    Chapter Fly Ash as a Cementitious Material for Concrete

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    This paper presents a review on fly ash as prime materials used for geopolymer. Due to its advantages of abundant resources, less in cost, great workability and high physical properties, fly ash leads to achieving high mechanical properties. Fly ash is considered as one of the largest generated industrial solid wastes or so-called industrial by-products, around the world particularly in China, India, and USA. The characteristics of fly ash allow it to be a geotechnical material to produce geopolymer cement or concrete as an alternative of ordinary Portland cement. Many efforts are made in this direction to formulate a suitable mix design of fly ash-based geopolymer by focusing on fly ash as the main prime material. The physical properties, chemical compositions, and chemical activation of fly ash are analyzed and evaluated in this review paper. Reference has been made to different ASTM, ACI standards, and other researches work in geopolymer area

    Utilization of bottom ash for alkali-activated (SI-AL) materials: a review

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    In Malaysia, 180 tons/day of solid waste bottom ash are produced by a Tanjung Bin power station, which is one of the four coal power plants in Malaysia. Hence, to overcome this problem, the solid waste could be used as source material in construction industry using geopolymer technique. Alkali-activated materials are introduced as an alternative materials to ordinary Portland cement (OPC) in the construction industry. There are many types of alkaline activator raw materi als such as bottom ash, fly ash, metakaolin and so on that can be substituted the materials existing such as cement and fine or course aggregate in the market now to make any production where the materials are coming from waste.The geopolymerization process involves a substantially fast chemical reaction under alkaline conditions with Si and Al minerals that results in a three‐dimensional polymeric chain and ring structure consisting of Si‐O‐Al‐O. The higher Si‐O‐Al‐O bonds are contained in the geopolymer, the higher compressive strength results will find. Several types of building materials such as

    Needs of Young African Neurosurgeons and Residents: A Cross-Sectional Study.

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    Introduction: Africa has many untreated neurosurgical cases due to limited access to safe, affordable, and timely care. In this study, we surveyed young African neurosurgeons and trainees to identify challenges to training and practice. Methods: African trainees and residents were surveyed online by the Young Neurosurgeons Forum from April 25th to November 30th, 2018. The survey link was distributed via social media platforms and through professional society mailing lists. Univariate and bivariate data analyses were run and a P-value < 0.05 was considered to be statistically significant. Results: 112 respondents from 20 countries participated in this study. 98 (87.5%) were male, 63 (56.3%) were from sub-Saharan Africa, and 52 (46.4%) were residents. 39 (34.8%) had regular journal club sessions at their hospital, 100 (89.3%) did not have access to cadaver dissection labs, and 62 (55.4%) had never attended a WFNS-endorsed conference. 67.0% of respondents reported limited research opportunities and 58.9% reported limited education opportunities. Lack of mentorship (P = 0.023, Phi = 0.26), lack of access to journals (P = 0.002, Phi = 0.332), and limited access to conferences (P = 0.019, Phi = 0.369) were associated with the country income category. Conclusion: This survey identified barriers to education, research, and practice among African trainees and young neurosurgeons. The findings of this study should inform future initiatives aimed at reducing the barriers faced by this group

    Children’s and adolescents’ rising animal-source food intakes in 1990–2018 were impacted by age, region, parental education and urbanicity

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    Animal-source foods (ASF) provide nutrition for children and adolescents’ physical and cognitive development. Here, we use data from the Global Dietary Database and Bayesian hierarchical models to quantify global, regional and national ASF intakes between 1990 and 2018 by age group across 185 countries, representing 93% of the world’s child population. Mean ASF intake was 1.9 servings per day, representing 16% of children consuming at least three daily servings. Intake was similar between boys and girls, but higher among urban children with educated parents. Consumption varied by age from 0.6 at <1 year to 2.5 servings per day at 15–19 years. Between 1990 and 2018, mean ASF intake increased by 0.5 servings per week, with increases in all regions except sub-Saharan Africa. In 2018, total ASF consumption was highest in Russia, Brazil, Mexico and Turkey, and lowest in Uganda, India, Kenya and Bangladesh. These findings can inform policy to address malnutrition through targeted ASF consumption programmes.publishedVersio
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