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A Qualitative Investigation of the Psychosocial Impact of Chronic Low Back Pain in Ghana
Get PDFIntroduction: Chronic low back pain (CLBP) is a global health concern associated with multidimensional/biopsychosocial levels of affectation in developed countries, with holistic management requiring consideration of these factors. There has been minimal research exploring the psychosocial impact of CLBP, and the factors influencing it, in African contexts, with none in Ghana.
Objectives: To explore the psychosocial impact of CLBP among patients with CLBP in Ghana.
Design: Qualitative study using individual semistructured face-to-face interviews, underpinned by Straussian grounded theory principles and critical realist philosophy.
Participants: Thirty patients with CLBP attending physiotherapy at two hospitals in Ghana.
Results: Five categories: loss of self and roles, emotional distress, fear, stigmatisation and marginalisation, financial burden, and social support and three mechanisms: acquired biomedical/mechanical beliefs from healthcare professionals (HCPs), sociocultural beliefs and the socioeconomic impact of CLBP were derived.
Conclusion: CLBP adversely affects multidimensional/biopsychosocial aspects of individuals experiencing CLBP in Ghana. This delineates the need for a biopsychosocial approach to care. There is the need for HCPs in Ghana to reassess current CLBP management strategies to address the influence of adverse HCPs biomedical inclinations on patients’ psychosocial consequences. Population-based education strategies and consideration of formal support systems for persons with disabling CLBP may also be beneficial
Are we there yet? The temporal dynamics of motoring branded content
Get PDFThe unprecedented petrol price hike in July 2022 did not see motorists falling out of love with the car. From the earliest days of motoring, it has always been more than engineering, performance and speed. This chapter explores the liminal space of the car and the specific temporal dynamics it affords and how this experience has been effectively utilised by branded content promotion. In particular two case studies are developed that map the transformation of the journey into an adventure through time and space: the Michelin Guide (1900) and the podcasts developed by Land Rover over a century later
A Human Ear-inspired Ultrasonic Transducer (HEUT) for 3-D Localization of Sub-wavelength Scatterers
No full textThe proposed technology aims to enable 3-D localization of scatterers using single-element ultrasonic transducers, which are traditionally limited to 1-D measurements. This is achieved by designing a bespoke acoustic lens with a spiral-shaped pattern similar to the human outer ear, a shape that has evolved for sound source localization. This lens breaks the surface symmetry of the transducer, allowing ultrasonic waves arriving from different directions to be encoded in a certain way that can later be decoded to extract directional information. By employing the mechanism of spatial-encoding of the received signals and decoding via signal processing, the location of sub-wavelength scatterers can be detected in 3-D with a single measurement for sparsely distributed scatterers. The proposed technology is first verified through a simulation study, and then 3-D printed acoustic lenses are used to demonstrate the 3-D encoding functionality of the Human Ear-inspired Ultrasonic Transducer (HEUT) experimentally. A framework is created to localize scatterers in 3-D by processing received signals acquired by a HEUT prototype. With this technology, a single transducer can obtain multi-dimensional information with a single pulse-echo measurement, reducing the number of elements required for performing 3-D ultrasound localization. The proposed spatial-encoding and –decoding technology can be applied to other wave-based imaging methods to develop affordable, practical and compact sensing devices
Twisted memories: Addiction-related engrams are strengthened by desire thinking.
Get PDFAssociative learning plays a central role in addiction by reinforcing associations between environmental cues and addiction-related information. Unsupervised learning models posit that memories are adjusted based on how strongly these representations are coactivated during the retrieval process. From a different perspective, clinical models of addiction posit that the escalation and persistence of craving may depend on desire thinking, a thinking style orienting to prefigure information about positive addiction-related experiences. In the present work, we tested the main hypothesis that desire thinking is a key factor in the strengthening of addiction-related associations. A group of adult smoking volunteers (N = 26) engaged in a period of desire thinking before performing an associative learning task in which neutral words (cues) were shown along with images (smoking-related vs. neutral context) at different frequencies. Two retrieval tests were administered, one immediately after encoding and the other after 24 h, to test how the recall of associations changed as a function of retention interval. Two control groups, smokers (N = 21) and non-smokers (N = 22), performed a similar procedure, with a neutral imagination task replacing desire thinking. Participants who engaged in desire thinking increased their performance from the first to the second retrieval test only for the most frequent smoking-related associations. Crucially, this selective effect was not observed in the two control groups. These results provide behavioral evidence in support of the idea that desire thinking plays a role in strengthening addiction-related associations. Thus, this thinking process may be considered a target for reconsolidation-based conceptualizations of, and treatments for, addiction. [Abstract copyright: Copyright © 2023 Elsevier Ltd. All rights reserved.
Spatial Fourier transform method to determine reflection and absorption coefficient of porous rigid materials applying Johnson-Champoux-Allard model
Get PDFSound absorption and reflection coefficients of the materials are two important parameters to understand the capacity of the materials to store acoustical energy. Spatial Fourier transform method is based on calculation of complex pressure distributions on two parallel surfaces and decomposing the complex pressure distributions into plane-wave components by using two-dimensional spatial Fourier transform which is used to separate the incident and reflected plane wave components. Johnson-Champoux-Allard model is utilized to predict effective density and bulk modulus of the air in the material, which are used to calculate wave number and characteristic impedance. Consequently, they are used to determine absorption and reflection coefficient of the porous materials at oblique angles
A simple copper(II) dppy-based receptor for sensing of L-cysteine and L-histidine in aqueous acetonitrile medium
Get PDFThe development of simple yet efficient receptors that rapidly detect and monitor amino acids with high sensitivity and reliability is crucial for the early-stage identification of various diseases. In this work, we report the synthesis and characterisation of a copper(II) complex, CuCl2L, by employing a 2,6-dipyrazinylpyridine (dppy)-based ligand (L = 2,2′-(4-(3,4,5-trimethoxyphenyl)pyridine-2,6-diyl)dipyrazine). The in situ prepared CuCl2L receptor exhibits an instantaneous response to the presence of L-cysteine (Cys) and L-histidine (His) in aqueous acetonitrile (4[thin space (1/6-em)]:[thin space (1/6-em)]1 v/v, 10 mM HEPES buffer, pH 7.4). Furthermore, competitive experiments demonstrate the selectivity of CuCl2L towards Cys (1 equiv.) in the vicinity of other L-amino acids in the aforementioned solvent conditions. The detection limits for Cys and His are calculated as 0.33 μM and 1.40 μM, respectively. DFT calculations offer a plausible explanation for the observed selectivity of the CuCl2L receptor towards Cys and His. They reveal that the most stable conformer of Cu[thin space (1/6-em)]:[thin space (1/6-em)]Cys complex (1[thin space (1/6-em)]:[thin space (1/6-em)]1) is a five-membered ring formed through N,S-coordination mode (ΔG = −26.7 kcal mol−1) over various other possible coordination modes, while comparable ΔG values are only obtained for Cu[thin space (1/6-em)]:[thin space (1/6-em)]His complexes featuring two His moieties
The journey from 5G towards 6G
Get PDFThis paper gives an overview of the journey from 5G towards 6G evolution. The 5G has been built across three main application verticals as defined by ITU, namely: Enhanced Mobile Broadband, Massive Machine Type Communications and Ultra-reliable Low Latency Communications (URRLC). To support these verticals, 5G has defined the following enablers: Massive MIMO, cloudification of network infrastructure, network automation, network slicing and edge cloud computing. It is expected that 5G will provide flexibility in terms of openness, mobility, programmability and agility and robustness in a standardized manner. The journey towards 6G will describe the limitations of 5G technologies and outlines the technology enablers for 6G. These enablers include smooth integration and interworking of Non-Terrestrial Networking technologies (NTN), use of Reconfigurable Intelligent Surfaces (RIS) and use of AI to orchestrate network and cloud resources. Additionally, the paper will give an overview of 6G research initiatives at both regional and international level
Mr-Nom: Multi-Scale Resolution of Neuronal Cells in Nissl-Stained Histological Slices Via Deliberate over-Segmentation and Merging
Get PDFIn comparative neuroanatomy, the characterization of brain cytoarchitecture is critical to a better understanding of brain structure and function, as it helps to distill information on the development, evolution, and distinctive features of different populations. The automatic segmentation of individual brain cells is a primary prerequisite and yet remains challenging. A new method (MR-NOM) was developed for the instance segmentation of cells in Nissl-stained histological images of the brain. MR-NOM exploits a multi-scale approach to deliberately over-segment the cells into superpixels and subsequently merge them via a classifier based on shape, structure, and intensity features. The method was tested on images of the cerebral cortex, proving successful in dealing with cells of varying characteristics that partially touch or overlap, showing better performance than two state-of-the-art methods
Mechanism of surface modification on monocrystalline silicon during diamond polishing at nanometric scale
Get PDFThe demand for polished silicon wafers has increased significantly in recent years to cater to the development of the semiconductor industry. For example, polished silicon wafer has direct applications in integrated circuits, radio frequency amplifiers, micro-processors, micro-electromechanical systems, etc. To carry out mechanical polishing, lapping, grinding, or single-point diamond turning of silicon, diamond abrasives were extensively used before the implementation of chemo-mechanical polishing. During the diamond-based polishing, a few problems have already been identified, such as the formation of an amorphous phase, heat-affected zones, low material removal, etc. Some research work has also reported that nano-structured abrasives lead to a thin layer of the amorphous phase and a better material removal rate. In the same direction, a molecular dynamics simulation is carried out in this paper to investigate the mechanism of material removal from monocrystalline silicon during the diamond-abrasive-based polishing process. The present work is mainly focused on the dynamics of material removal phenomena near the abrasive particles at the nanometric scale by considering stress, lattice, cohesive energy, etc. This reveals that a higher value of indentation force results in surface buckling, which creates a zone of both compressive and tensile stresses, which increases the coordination number and forms β-silicon just ahead of the abrasive particle. This mechanism happens by developing a β-silicon phase on the surface with a thickness beyond a certain value of indentation force on the zone of compression. Buckling on this phase happens due to stress localisation in compression, as the flow stress of this phase is less than that of diamond cubic lattices. To avoid the mechanism of surface buckling and process silicon material on the surface, the indentation force needs to be maintained below a critical value. In the present case, it was found that the indentation force of less than or equal to 190 nN for the abrasive size of ϕ8 nm does the material removal by surface processing only without surface buckling. It was also found that surface processing helps to reduce the depth of the amorphous layer significantly without compromising the material removal rate or the generation of a wavy surface. Thus, the present mechanism will help in the polishing of silicon with minimum defects and reduce processing time for the final stage of polishing towards manufacturing ultra-smooth and planer surfaces
Atomistic study on the effect of the size of diamond abrasive particle during polishing of stainless steel
Get PDFNanofinishing or polishing helps to reduce surface roughness, which further improves both the optical and chemical properties of engineering materials. During the polishing of any engineering material, the size of abrasive particles plays a significant role in efficient polishing. In this paper, stainless steel 304 (or SS304) is selected for polishing through diamond abrasives with varying particle sizes using molecular dynamics simulations (MDS). It is found that the diamond abrasive particle initially causes elastic deformation due to the attractive force between the abrasive particle and the workpiece surface. As the size of the abrasive particle increases, plastic deformation occurs by spreading the dislocations on the surface only, which helps to annihilate the dislocations after polishing. It is revealed that the smaller abrasive particles (<3 nm) get trapped due to strong chemical bonding with the surface of the workpiece, and the abrasive particles start depositing on the workpiece instead of material removal. In this paper, it is proposed that an optimum size of abrasive particles is required for a given set of polishing parameters to achieve efficient material removal and minimum surface and subsurface defects. Thus, the present study is worthwhile for efficient polishing or nanocutting of stainless steel through monocrystalline diamond