3,504 research outputs found
The Structure and Function of the Retina in Multiple Sclerosis
Background: Multiple sclerosis (MS) is a complex heterogenous autoimmune inflammatory disease with a prolonged and variable time course. The visual system is frequently implicated, either as the presenting symptom, or, with advancement of the disease. This has been documented in the literature with changes in visual acuity (VA) that are accompanied by functional changes in the optic nerve, measured with the visual evoked potential (VEP) and possible retrograde degeneration involving the retinal ganglion cells in the retina, measured with the pattern reversal electroretinogram (PERG). However, inflammatory episodes may be clinical or subclinical in nature and may go unrecognised. Originating from the same embryological origins, the effect of inflammation in MS on the on the retina is less well known. The research hypothesis was that there is a measurable difference in the function of retinal cells in patients with newly diagnosed multiple sclerosis, suggestive of inflammatory retinopathy compared to healthy controls.
The overall aim was to investigate any differences in the electrophysiological function of the visual pathway of patients newly diagnosed with MS compared to healthy controls.
Methods: The visual system is explored with clinical (VA), electrophysiology (VEP and electroretinography (ERG – pattern and flash) and structural (OCT) measures, in patients presenting with symptoms suggestive of MS to a specialist service. This prospective case control study investigates the visual pathway at the earliest stage of the disease to look for differences in structure and function between patients and healthy volunteers that might serve as a biomarker in the future.
Results: There were a number of variables that were significantly different between the two groups, logistic regression analysis found that VA (p 0.038) and VEP P100 peak-time (p 0.014) from the right eye as significant. Dividing the participants by prolongation of the VEP P100 peak-time as defined in clinical practice, found a number of ERG amplitude variables as well as VA that were consistently different between the groups regardless of symptoms.
Conclusion: The study confirms optic nerve involvement in MS with VEP and VA abnormalities consistent with the literature in this cohort. Additionally, VA and some ERG amplitude variables were significantly reduced in participants with MS, when grouped according to VEP P100 peak-time, suggesting inner and outer retinal changes. Further work would be required to confirm these findings. No OCT structural changes were found in any of the analysis that included the macula thickness, ganglion cell layer or retinal nerve fibre layer.
Keywords: multiple sclerosis (MS), visual evoked potential (VEP), pattern electroretinogram (PERG), electroretinogram (ERG), optical coherence tomography (OCT
Proceedings of the 10th International congress on architectural technology (ICAT 2024): architectural technology transformation.
The profession of architectural technology is influential in the transformation of the built environment regionally, nationally, and internationally. The congress provides a platform for industry, educators, researchers, and the next generation of built environment students and professionals to showcase where their influence is transforming the built environment through novel ideas, businesses, leadership, innovation, digital transformation, research and development, and sustainable forward-thinking technological and construction assembly design
Combined Nutrition and Exercise Interventions in Community Groups
Diet and physical activity are two key modifiable lifestyle factors that influence health across the lifespan (prevention and management of chronic diseases and reduction of the risk of premature death through several biological mechanisms). Community-based interventions contribute to public health, as they have the potential to reach high population-level impact, through the focus on groups that share a common culture or identity in their natural living environment. While the health benefits of a balanced diet and regular physical activity are commonly studied separately, interventions that combine these two lifestyle factors have the potential to induce greater benefits in community groups rather than strategies focusing only on one or the other. Thus, this Special Issue entitled “Combined Nutrition and Exercise Interventions in Community Groups” is comprised of manuscripts that highlight this combined approach (balanced diet and regular physical activity) in community settings. The contributors to this Special Issue are well-recognized professionals in complementary fields such as education, public health, nutrition, and exercise. This Special Issue highlights the latest research regarding combined nutrition and exercise interventions among different community groups and includes research articles developed through five continents (Africa, Asia, America, Europe and Oceania), as well as reviews and systematic reviews
Advances and Applications of DSmT for Information Fusion. Collected Works, Volume 5
This fifth volume on Advances and Applications of DSmT for Information Fusion collects theoretical and applied contributions of researchers working in different fields of applications and in mathematics, and is available in open-access. The collected contributions of this volume have either been published or presented after disseminating the fourth volume in 2015 in international conferences, seminars, workshops and journals, or they are new. The contributions of each part of this volume are chronologically ordered.
First Part of this book presents some theoretical advances on DSmT, dealing mainly with modified Proportional Conflict Redistribution Rules (PCR) of combination with degree of intersection, coarsening techniques, interval calculus for PCR thanks to set inversion via interval analysis (SIVIA), rough set classifiers, canonical decomposition of dichotomous belief functions, fast PCR fusion, fast inter-criteria analysis with PCR, and improved PCR5 and PCR6 rules preserving the (quasi-)neutrality of (quasi-)vacuous belief assignment in the fusion of sources of evidence with their Matlab codes.
Because more applications of DSmT have emerged in the past years since the apparition of the fourth book of DSmT in 2015, the second part of this volume is about selected applications of DSmT mainly in building change detection, object recognition, quality of data association in tracking, perception in robotics, risk assessment for torrent protection and multi-criteria decision-making, multi-modal image fusion, coarsening techniques, recommender system, levee characterization and assessment, human heading perception, trust assessment, robotics, biometrics, failure detection, GPS systems, inter-criteria analysis, group decision, human activity recognition, storm prediction, data association for autonomous vehicles, identification of maritime vessels, fusion of support vector machines (SVM), Silx-Furtif RUST code library for information fusion including PCR rules, and network for ship classification.
Finally, the third part presents interesting contributions related to belief functions in general published or presented along the years since 2015. These contributions are related with decision-making under uncertainty, belief approximations, probability transformations, new distances between belief functions, non-classical multi-criteria decision-making problems with belief functions, generalization of Bayes theorem, image processing, data association, entropy and cross-entropy measures, fuzzy evidence numbers, negator of belief mass, human activity recognition, information fusion for breast cancer therapy, imbalanced data classification, and hybrid techniques mixing deep learning with belief functions as well
Treating High Salinity Produced Water Using Hybrid Membrane Processes: Electrocoagulation-Microfiltration/Ultrafiltration-Membrane Distillation-Crystallization
Produced water (PW) is considered the largest industrial wastewater stream in the world. PW generated from oil and gas operations generally contains a range of contaminants including high total dissolved solids, high total suspended solids, polar and nonpolar organic compounds, and low surface tension dissolved species. Treating PW is very challenging and applying only membrane-based technologies is not sufficient due to membrane fouling, which affects their long-term performance. Hence, integrated membrane processes are required to treat PW effectively. Hybrid membrane processes, which may result from combining a conventional process with a membrane separation, could be used to address the issues of fouling (and wetting), and maximize water recovery. In this dissertation, several hybrid membrane processes are reviewed and the effects of important parameters that determine the performance of these hybrid systems are discussed. While the highly impaired PW is often deep well injected, there is a great deal of interest in treating and recovering this water for beneficial uses. However, the need to use multiple unit operations is essential if these wastewaters are to be recovered. Electrocoagulation (EC) is considered a promising pretreatment technology. In this study, the use of aluminium electrodes for electrocoagulation as a pretreatment operation was investigated. The effects of electrode arrangement, applied current, reaction time, initial pH, and inter electrode distance on the quality of the treated water have been investigated. EC results showed good removal of turbidity (95%), total suspended solids, TSS (90%), and total organic carbon, TOC (70%) by carefully choosing the reaction conditions. Sedimentation was used to separate the treated water from the sludge. The quality of the feed PW can strongly affect the performance of the EC. In addition, a combined electrocoagulation – microfiltration – membrane distillation (EC-MF-MD) process had been used to treat PW. In this work, EC was followed by MF to pretreat the wastewater prior to MD. After EC, the TOC was reduced from 120 mg L-1 to 64 mg L-1. Tangential flow MF using a 0.1 micrometer pore size polyethersulfone membrane was used to separate the particulate matter after EC and to further reduce the TOC to 44 mg L-1. MD was used to desalinate the pretreated PW resulting in a high quality treated water (reducing the total dissolved solids (TDS) concentration from 245,300 mg L-1 to 56 mg L-1). Three membranes with very different surface morphology were tested here: commercially available polyvinylidene fluoride, electrospun poly (vinylidene fluoride-co-hexafluoropropylene) nanofibers and multiwalled carbon nanotube coated polytetrafluoroethylene. The surface properties of an ideal membrane that is resistant to wetting and provides high flux is likely to depend on the TDS and properties of the PW. The integrated electrocoagulation-ultrafiltration-membrane distillation and crystallization process (EC-UF-MDC) was also used to treat PW. The focus of this work was to determine the feasibility of this integrated process for increasing water recovery. The results of this work suggest that optimizing the various unit operations in this integrated process could be used to recover PW. Dissolved organic compounds are known to foul the hydrophobic membrane used in MD. In this study, a significant reduction in membrane fouling was obtained by EC pretreatment, which can lead to a long-term durability of MD system. In addition, the use of MDC can help mitigate the scale formation. Also, treating PW will preserve surface and groundwater, which form 80% of the water utilized in hydraulic fracturing, and reduce the amount of PW directly disposed in Class II disposal wells, which further address the main cause of earthquakes. Finally, the integrated EC-MF pilot-scale system will be used to pretreat and reuse PW. The EC reactor (37.5 L) was built based on experiences gained from working with a laboratory scale (1 L). The integrated process will be evaluated at Texas Tech University (TTU). The design and construction of the EC-MF system are discussed in this work. The pilot-scale system has a capacity of treating 3600 L/day PW. The system layout is also discussed in this study. The EC-MF process was designed based on 70% feed water recovery. Turbidity, TSS, and TOC analysis will be obtained for samples collected during the 5 days operation. The goal of this work is to achieve a reduction of 95, 90, and 70% for turbidity, TSS, and TOC, respectively, which is the pretreated PW quality needed to be further treated by TTU
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Policy options for food system transformation in Africa and the role of science, technology and innovation
As recognized by the Science, Technology and Innovation Strategy for Africa – 2024 (STISA-2024), science, technology and innovation (STI) offer many opportunities for addressing the main constraints to embracing transformation in Africa, while important lessons can be learned from successful interventions, including policy and institutional innovations, from those African countries that have already made significant progress towards food system transformation. This chapter identifies opportunities for African countries and the region to take proactive steps to harness the potential of the food and agriculture sector so as to ensure future food and nutrition security by applying STI solutions and by drawing on transformational policy and institutional innovations across the continent. Potential game-changing solutions and innovations for food system transformation serving people and ecology apply to (a) raising production efficiency and restoring and sustainably managing degraded resources; (b) finding innovation in the storage, processing and packaging of foods; (c) improving human nutrition and health; (d) addressing equity and vulnerability at the community and ecosystem levels; and (e) establishing preparedness and accountability systems. To be effective in these areas will require institutional coordination; clear, food safety and health-conscious regulatory environments; greater and timely access to information; and transparent monitoring and accountability systems
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