Effect of Luffa cylindrica fiber and particulate on the mechanical properties of epoxy

This study examines the effect of addition of Luffa cylindrica fiber (LCF) and Luffa cylindrica particulate (LCP) on the properties of epoxy resin. Luffa cylindrica fiber treated with 8% NaOH and of 2, 4, and 6% weight fraction was used to reinforce epoxy resin via hand lay-up method. Hybridization of the fiber and particulate was also done with the particulate having a constant weight fraction of 10% whereas the fibers were varied as in the mono-reinforced Luffa cylindrica fiber composite. The samples were machined for mechanical and microstructural analysis. Result showed that addition of the reinforcement led to an improvement in mechanical properties. However, the hybrid was seen to showcase better properties compared to the fiber-reinforced composite with the hybrid sample of composition 4 wt% LCF and 10 wt% LCP exhibiting the highest tensile and flexural strength of 13.489 MPa and 20.3 MPa, respectively. Microstructural analysis showed excellent homogeneity with few voids and better adhesion between the reinforcement and matrix. These results show that this composite can find application in the interior and exterior parts of automobiles as well as in household wares like flower pots

Old age and depression in Ghana: assessing and addressing diagnosis and treatment gaps

Background: There is limited evidence about the prevalence of depression among older people in sub-Saharan Africa, about access to treatment or the potential efficacy of community-based interventions. Objective: Using nationally representative data from the WHO SAGE survey, examine the prevalence of and factors associated with depression among people aged 50 and over in Ghana. Compare self-reported diagnosis and a symptom algorithm to assess treatment gaps and factors associated with the size of gap. Assess the feasibility of a small community-based intervention specifically for older people. Method: Prevalence and treatment data were taken from the WHO SAGE 2007 survey in Ghana, including 4,725 people aged 50 or over. Outcomes of interest were self-reported depression and diagnosis of depression derived from a symptom-based algorithm. The data were subjected to bivariate and multivariate analysis. In parallel, a pilot intervention was conducted with 35 older people, which included screening by a trained psychiatrist and follow-up group sessions of psychotherapy. Results: The symptomatic algorithm reported an overall rate of 9.2 per cent for the study population, with associations with female sex and older age. The treatment gap for these cases was found to be 83.0 per cent. The implementation of the pilot study was perceived as effective and replicable by stakeholders and there was so evidence of enhanced outcomes for people with mild depression. Conclusions: Large numbers of older people in Ghana experience depression, but very few have access to treatment. There is an urgent need to develop and validate community-based services for older people experiencing this condition

The mathematical simulation of the temperature fields of building envelopes under permanent frozen soil conditions

The physical-mathematical model of the thermal state of the aired technical underground taking into account the air exchange and design features of construction under permanent frozen soil conditions has been suggested. The computational scheme of the temperature fields prediction of building envelopes of projected buildings and soil under and nearby buildings has been developed. The numerical simulation of the temperature fields of building envelopes changes was conducted during a year. The results of the numerical simulation showed that the heat coming from the technical undergrounds and through the walls does not influence the temperature field of the soil neither under a building nor at a distance from it

Coagulation factors and natural anticoagulants as surrogate markers of preeclampsia and its subtypes: A case-control study in a Ghanaian population

Preeclampsia (PE) is associated with endothelial injury and hemostatic abnormalities. However, the diagnostic role of coagulation parameters and natural anticoagulants in predicting PE has not been explored in Ghana. This study assessed plasma levels of these factors as surrogate markers of PE and its subtypes. This case-control study included 90 women with PE (cases) and 90 normotensive pregnant women (controls). Blood samples were drawn for the estimation of complete blood count and coagulation tests. The prothrombin time (PT), activated partial thromboplastin time (APTT), and the calculation of the international normalized ratio (INR) were determined by an ACL elite coagulometer while the levels of protein C (PC), protein S (PS), antithrombin III (ATIII), and D-dimers were also measured using the solid-phase sandwich enzyme-linked immunosorbent assay (ELISA) method. All statistical analyses were performed using the R Language for Statistical Computing. Results showed significantly (p \u3c .05) shortened APTT (28.25 s) and higher D-dimer levels (1219.00 ng/mL) among PE women, as well as low levels of PC (1.02 g/mL), PS (6.58 g/mL), and ATIII (3.99 ng/mL). No significant difference was found in terms of PT and INR. From the receiver operating characteristic analysis, PC, PS, and ATIII could significantly predict PE and its subtypes at certain cutoffs with high accuracies (area under the curve [AUC] ≥ 0.70). Most women with PE are in a hypercoagulable state with lower natural anticoagulants. PC, PS, and ATIII are good predictive and diagnostic markers of PE and its subtypes (early-onset PE [EO-PE] and late-onset PE [LO-PE]) and should be explored in future studies

Clinical course of cone dystrophy caused by mutations in the RPGR gene

Contains fulltext : 97720.pdf (publisher's version ) (Closed access)BACKGROUND: Mutations in the RPGR gene predominantly cause rod photoreceptor disorders with a large variability in clinical course. In this report, we describe two families with mutations in this gene and cone involvement. METHODS: We investigated an X-linked cone dystrophy family (1) with 25 affected males, 25 female carriers, and 21 non-carriers, as well as a small family (2) with one affected and one unaffected male. The RPGR gene was analyzed by direct sequencing. All medical records were evaluated, and all available data on visual acuity, color vision testing, ophthalmoscopy, fundus photography, fundus autofluorescence, Goldmann perimetry, SD-OCT, dark adaptation, and full-field electroretinography (ERG) were registered. Cumulative risks of visual loss were studied with Kaplan-Meier product-limit survival analysis. RESULTS: Both families had a frameshift mutation in ORF15 of the RPGR gene; family 1 had p.Ser1107ValfsX4, and family 2 had p.His1100GlnfsX10. Mean follow up was 13 years (SD 10). Virtually all affected males showed reduced photopic and normal scotopic responses on ERG. Fifty percent of the patients had a visual acuity of <0.5 at age 35 years (SE 2.2), and 75% of the patients was legally blind at age 60 years (SE 2.3). Female carriers showed no signs of ocular involvement. CONCLUSIONS: This report describes the clinical course and visual prognosis in two families with cone dystrophy due to RPGR mutations in the 3' terminal region of ORF15. Remarkable features were the consistent, late-onset phenotype, the severe visual outcome, and the non-expression in female carriers. Expression of RPGR mutations in this particular region appears to be relatively homogeneous and predisposed to cones

Phytochemical and in vitro antioxidant assessment of Yoyo bitters

In this paper, herbal bitters are widely used due to their numerous acclaimed health benefits in many Nigerian homes; however, many have not been subjected to scientific scrutiny. The aim of this study was to determine the phytochemical composition and antioxidant capacity of a non-alcoholic polyherbal formulation, Yoyo bitters, towards validating its broad pharmacological claims. The phytochemical components of Yoyo bitters were ascertained by phytochemical screening assays and gas chromatography-mass spectrometry (GC-MS). The antioxidant activity was investigated in vitro using 2,2-diphenyl-1-picryhydrazyl (DPPH) radical, hydrogen peroxide (H2O2) scavenging activity, total antioxidant capacity (TAC) and ferric reducing antioxidant power (FRAP) assays. Qualitative phytochemical analysis of Yoyo bitters showed the presence of saponins, tannins, flavonoids, terpenoids, cardiac glycosides and anthocyanins. The total phenols, flavonoids, flavanols, tannins and carotenoids content were 14.741 ±0.64 mg GAE/ml, 0.152 ±0.01 mg RE/ml, 0.437 ±0.02 mg RE/ml, 0.368 ±0.04 mg TAE/ml and 0.016 ±0.00 mg CAE/ml respectively. GC-MS chromatogram revealed the presence of forty-three (43) phytochemical compounds with D-allose (41.81%), 1,6-anhydro-beta-D-glucofuranose (24.15%), 5-hydroxymethylfurfural (8.02%) and Z-6-pentadecen-1-ol acetate (3.50%) as the most abundant constituents. Yoyo bitters demonstrated effective antioxidant activity against DPPH and H2O2 with IC50 values of 0.492 mg/ml and 0.629 mg/ml respectively compared to ascorbic acid of 0.161 mg/ml and 0.130 mg/ml respectively. Total antioxidant capacity and ferric reducing antioxidant power of Yoyo bitters were 0.432 mg AAE/ml and 2.236 mg AAE/ml respectively. This study validates the antioxidant capacity of Yoyo bitters and provides chemical basis for its acclaimed pharmacological actions

Exploring Radio Frequency Techniques for Bone Fracture Detection: A Comprehensive Review of Low Frequency and Microwave Approaches

YesThis comprehensive review paper examines bone fracture detection techniques based on time-domain low-frequency and microwave radiofrequency (RF). Early and accurate diagnosis of bone fractures remains critical in healthcare, as it can significantly improve patient outcomes. This review focuses on the potential of low-frequency and microwave RF methods, particularly their combination and application of time-domain analysis for enhanced fracture detection. We begin by providing an overview of the fundamental concepts of RF techniques and then by examining biological tissues' dielectric properties. We then compare the advantages and limitations of various bone fracture detection techniques, such as low-frequency RF methods, microwave RF methods, ultrasonography, X-ray, and CT scans. The discussion then shifts to hybrid approaches that combine low-frequency and microwave techniques, emphasising the advantages of such combinations in fracture detection. Machine learning techniques, their applications in bone fracture detection, and the role of time-domain analysis in hybrid approaches are also investigated. Finally, we examine the accuracy and reliability of simulated models for bone fracture detection. We discuss recent advancements and future directions, such as novel sensor technologies, improved signal processing techniques, integration with medical imaging modalities, and personalised fracture detection approaches. This review aims to comprehensively understand the landscape and future potential of time-domain analysis in low-frequency and microwave RF techniques for bone fracture detection.EU Horizon Europe H2020-MSCA-RISE-2022-2027 (ID: 101086492) and H2020-MSCA-RISE-2019-2024 (ID 872878), Marie Skłodowska-Curie, Research and Innovation Staff Exchange (RISE), and the financial support from the UK Engineering and Physical Sciences Research Council (EPSRC) under grant EP/ X039366/1

An exploration of secondary students' mental states when learning about acids and bases

This study explored factors of students’ mental states, including emotion, intention, internal mental representation, and external mental representation, which can affect their learning performance. In evaluating students’ mental states during the science learning process and the relationship between mental states and learning achievement, valid, reliable, and scalable measures of students’ mental states and learning achievement are needed. This paper presents the development of the Mental State Conceptual Learning Inventory (MSCLI) to identify students’ mental states before and after learning about acids and bases. This instrument is time efficient and convenient and can be administered to large student samples so that teachers and researchers can gain profound insights into their students’ learning of acids and bases in science class. The results of this study indicate that students’ mental states are highly correlated with their achievement. As a whole, low-achieving students tended to have negative emotions and low intentions, were not good at internal visualization, and were unable to interpret graphics and draw pictures. In contrast, high-achieving students had positive emotions and intentions when learning life-related topics about acids and bases, and were good at internal visualization and drawing and interpreting graphics

Revisiting QRS detection methodologies for portable, wearable, battery-operated, and wireless ECG systems

Cardiovascular diseases are the number one cause of death worldwide. Currently, portable battery-operated systems such as mobile phones with wireless ECG sensors have the potential to be used in continuous cardiac function assessment that can be easily integrated into daily life. These portable point-of-care diagnostic systems can therefore help unveil and treat cardiovascular diseases. The basis for ECG analysis is a robust detection of the prominent QRS complex, as well as other ECG signal characteristics. However, it is not clear from the literature which ECG analysis algorithms are suited for an implementation on a mobile device. We investigate current QRS detection algorithms based on three assessment criteria: 1) robustness to noise, 2) parameter choice, and 3) numerical efficiency, in order to target a universal fast-robust detector. Furthermore, existing QRS detection algorithms may provide an acceptable solution only on small segments of ECG signals, within a certain amplitude range, or amid particular types of arrhythmia and/or noise. These issues are discussed in the context of a comparison with the most conventional algorithms, followed by future recommendations for developing reliable QRS detection schemes suitable for implementation on battery-operated mobile devices.Mohamed Elgendi, Björn Eskofier, Socrates Dokos, Derek Abbot