362 research outputs found
Prediction of elastic modulus for fibre-reinforced soil-cement mixtures: a machine learning approach
Soil-cement mixtures reinforced with fibres are an alternative method of chemical soil stabilisation in which the inherent disadvantage of low or no tensile or flexural strength is overcome by incorporating fibres. These mixtures require a significant amount of time and resources for comprehensive laboratory characterisation, because a considerable number of parameters are involved. Therefore, the implementation of a Machine Learning (ML) approach provides an alternative way to predict the mechanical properties of soil-cement mixtures reinforced with fibres. In this study, Artificial Neural Networks (ANNs), Support Vector Machines (SVMs), Random Forest (RF), and Multiple Regression (MR) algorithms were trained for predicting the elastic modulus of soil-cement mixtures reinforced with fibres. For ML algorithms training, a dataset of 121 records was used, comprising 16 properties of the composite material (soil, binder, and fibres). ANN and RF showed a promising determination coefficient (R2 ≥ 0.93) on elastic modulus prediction. Moreover, the results of the proposed models are consistent with the findings that the fibre and binder content have a significant effect on the elastic modulus.This research was partly financed by FCT/MCTES through national funds (PIDDAC) under
the R&D Unit Institute for Sustainability and Innovation in Engineering Structures (ISISE), under reference UIDB/04029/2020, the R&D Unit Chemical Process Engineering and Forest Products Research
Centre (CIEPQPF) under reference UIDB/00102/2020, and under the project PTDC/ECICON/28382/2017
Assessment of knowledge and treatment practices of hepatitis B infection in children among health professionals in Krachi districts in Ghana:a cross-sectional study
Background. Hepatitis B virus (HBV) infection remains one of the neglected infectious diseases. Children infected with HBV are at higher risk of becoming chronic carriers. Barriers to measures against HBV in children are attributed to inadequate knowledge by some health professionals. This study assessed knowledge and treatment practices of HBV in children among health professionals. Materials and Methods. A cross-sectional survey was conducted among health professionals (185) in three districts in Krachi using a structured questionnaire. Stata version 15 was used to analyze participants’ responses on awareness, knowledge, and treatment practices. Pearson’s product-moment correlation was used to determine the relationship between knowledge and treatment practices. Multivariate regression analysis assessed the relationships between variables at P<0.05 and 95% confidence interval. Results. 20% were not aware of HBV in children and 85% had only fair knowledge about HBV in children. Only 29% indicated good knowledge and treatment practices of HBV in children. A unit increase in knowledge of HBV in children leads to a 1.42 unit increase in awareness (P<0.01), and a 1.3 unit increase in treatment practice (P<0.01) of HBV in children. Conclusions. Participants demonstrated only fair knowledge about HBV in children. Seminars and workshops on HBV in children for health professionals must intensify.</p
PUM1 Mediates the Posttranscriptional Regulation of Human Fetal Hemoglobin
The fetal-to-adult hemoglobin switching at about the time of birth involves a shift in expression from γ-globin to β-globin in erythroid cells. Effective re-expression of fetal γ-globin can ameliorate sickle cell anemia and β-thalassemia. Despite the physiological and clinical relevance of this switch, its posttranscriptional regulation is poorly understood. Here, we identify Pumilo 1 (PUM1), an RNA-binding protein with no previously reported functions in erythropoiesis, as a direct posttranscriptional regulator of β-globin switching. PUM1, whose expression is regulated by the erythroid master transcription factor erythroid Krüppel-like factor (EKLF/KLF1), peaks during erythroid differentiation, binds γ-globin messenger RNA (mRNA), and reduces γ-globin (HBG1) mRNA stability and translational efficiency, which culminates in reduced γ-globin protein levels. Knockdown of PUM1 leads to a robust increase in fetal hemoglobin (∼22% HbF) without affecting β-globin levels in human erythroid cells. Importantly, targeting PUM1 does not limit the progression of erythropoiesis, which provides a potentially safe and effective treatment strategy for sickle cell anemia and β-thalassemia. In support of this idea, we report elevated levels of HbF in the absence of anemia in an individual with a novel heterozygous PUM1 mutation in the RNA-binding domain (p.(His1090Profs∗16); c.3267_3270delTCAC), which suggests that PUM1-mediated posttranscriptional regulation is a critical player during human hemoglobin switching
In-Vitro Assessment of Antioxidant and Antimicrobial Activities of Methanol Extracts of Six Wound Healing Medicinal Plants
In this study, quantitative values of antioxidant activity of crude methanolic extracts of five Wound healing medicinal plants (Amaranthus spinosus, Anogeissus leiocarpus, Spondia monbin, Corchorus olitorius, and Mallotus oppositifolia) were investigated. The investigation used DPPH (1, 1-diphenyl-2-picrylhydrazyl) free radical as a substrate and Ferric reducing antioxidant power (FRAP) assay to determine both scavenging ability and the reducing properties. Antioxidant was further analysed quantitatively for flavonoid content, total phenolic content in the crude methanolic extracts using spectrophotometric assay. The result showed that all plants exhibited scavenging ability and strong reducing activity although the ability differed markedly among the various plant samples. The highest scavenging ability (% inhibition) was exhibited by A. leiocarpus (95.86 ± 0.1) followed by C. olitorius (94.19 ± 0.06) while the lowest was from A. spinosus (40.87±2.5). The reducing power was also highest in A. leiocarpus followed by S. monbin; while A. spinosus showed the least reducing power. In quantitative analysis, again A. leiocarpus was found to have the highest phenolic content (1294.81± 3.0 mg/g) with A. spinosus recording the least phenol and flavonoid content. The crude methanol extracts were also screened for their antimicrobial activity against four common pathogenic microorganisms (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Citrobacter sp.) associated with wound infection by well diffusion method. All the extracts were found to inhibit the growth of both gram (+) and gram (-) bacteria organisms tested. Keywords: Radical scavenging effect, phenolic compounds, antioxidant activit
Public choice theory and rental housing: an examination of rental housing contracts in Ghana
This paper extends both the literature on rental housing in Ghana and the global literature on the critique of public choice analyses in terms of focus, methods, and positioning. It argues that, contrary to the assumption that all housing policy changes are driven by internal national processes, in the case of Ghana at least, neither tenants (through their use of their greater numbers) nor landlords (through the use of their stronger financial and hence political power) exclusively influence housing policy. Both parties have some power, but landlords use theirs to change rents arbitrarily and decide whom to invite or keep as tenants, while tenants seek to use their power by lodging complaints with the state, albeit to little effect as the power of landlords is overwhelming. There is a strong basis to call into question the public choice argument that it is fair for landlords to extract windfall rent from tenants since their efforts or talents do not increase rent
Multispectral Imaging for Microchip Electrophoresis Enables Point-of-Care Newborn Hemoglobin Variant Screening
Hemoglobin (Hb) disorders affect nearly 7% of the world\u27s population. Globally, around 400,000 babies are born annually with sickle cell disease (SCD), primarily in sub-Saharan Africa where morbidity and mortality rates are high. Screening, early diagnosis, and monitoring are not widely accessible due to technical challenges and cost. We hypothesized that multispectral imaging will allow sensitive hemoglobin variant identification in existing affordable paper-based Hb electrophoresis. To test this hypothesis, we developed the first integrated point-of-care multispectral Hb variant test: Gazelle-Multispectral. Here, we evaluated the accuracy of Gazelle-Multispectral for Hb variant newborn screening in 265 newborns with known hemoglobin variants including hemoglobin A (Hb A), hemoglobin F (Hb F), hemoglobin S (Hb S) and hemoglobin C (Hb C). Gazelle-Multispectral detected levels of Hb A, Hb F, Hb S, and Hb C/E/A2, demonstrated high correlations with the results reported by laboratory gold standard high performance liquid chromatography (HPLC) at Pearson Correlation Coefficient = 0.97, 0.97, 0.93, and 0.95. Gazelle-Multispectral demonstrated accuracy of 96.8% in subjects of 0–3 days, and 96.9% in newborns. The ability to obtain accurate results on newborn samples suggest that Gazelle-Multispectral can be suitable for large-scale newborn screening and for diagnosis of SCD in low resource settings
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