Search Results (4,564)

Background: Focal mechanical vibration therapy has gained attention as a potential intervention to improve motor function while decreasing spasticity and pain in post-stroke patients. Despite promising results, there remains variability in study designs and outcomes, warranting a review of its clinical efficacy. Methods: A review was conducted to evaluate randomized controlled trials (RCTs) investigating the effects of focal mechanical vibration therapy on post-stroke rehabilitation. Six studies were included, assessing outcomes such as spasticity reduction (using the Modified Ashworth Scale), motor function recovery (Wolf Motor Function Test, Fugl-Meyer Assessment), and pain management (Visual Analog Scale, Numerical Rating Scale). The quality of studies was evaluated using the PEDro scale and RoB-2 tool. An overview review was conducted to provide a comprehensive analysis of the topic. Results: The included studies demonstrated significant reductions in spasticity and improvements in motor function in most patients receiving focal vibration therapy. Notable improvements were observed when focal vibration was combined with other rehabilitation techniques, such as progressive modular rebalancing or robotic rehabilitation. Pain levels were also reduced in several studies. However, differences in vibration parameters (frequency, amplitude), small sample sizes, and short follow-up periods limit the generalizability of the findings. Conclusions: Focal mechanical vibration therapy appears to be an effective adjunct in post-stroke rehabilitation, particularly for reducing spasticity and improving motor function. Although short-term benefits are promising, further research is required to determine long-term efficacy and optimal treatment parameters. This review evaluates the effectiveness of focal vibration therapy in treating motor deficits and spasticity in post-stroke patients. The results suggest its potential to improve these conditions, though further studies with larger sample sizes are needed to confirm its long-term efficacy. Full article

In recent years, the efficiency of high-efficiency Cu(In,Ga)Se₂ (CIGS) solar cells has been significantly improved, particularly for narrow-gap types. One of the key reasons for the enhancement of narrow-gap device performance is the formation of the “Spike” structure at the CdS/CIGS heterojunction interface. Wide-gap CIGS solar cells excel in modular production but lag behind in efficiency compared to narrow-gap cells. Some studies suggest that the “Cliff” structure at the heterojunction of wide-gap CIGS solar cells may be one of the factors contributing to this decreased efficiency. This paper utilizes the SCAPS software, grounded in the theories of semiconductor physics and photovoltaic effects, to conduct an in-depth analysis of the impact of “Cliff” and “Spike” heterojunction structures on the performance of wide band gap CIGS solar cells through numerical simulation methods. The aim is to verify whether the “Spike” structure is also advantageous for enhancing wide-gap CIGS device performance. The simulation results show that the “Spike” structure is beneficial for reducing interfacial recombination, thereby enhancing the V_OC of wide-gap cells. However, an electronic transport barrier may form at the heterojunction interface, resulting in a decrease in J_SC and FF, which subsequently reduces device efficiency. The optimal heterojunction structure should exhibit a reduced “Cliff” degree, which can facilitate the reduction of interfacial recombination while simultaneously preventing the formation of an electronic barrier, ultimately enhancing both V_OC and device performance. Full article

Over the past few decades, wind energy has expanded to become a widespread, clean, and sustainable energy source. However, integrating offshore wind energy with the onshore AC grids presents many stability and control challenges that hinder the reliability and resilience of AC grids, particularly during faults. To address this issue, current grid codes require offshore wind farms (OWFs) to remain connected during and after faults. This requirement is challenging because, depending on the fault location and power flow direction, DC link over- or under-voltage can occur, potentially leading to the shutdown of converter stations. Therefore, this necessitates the proper understanding of key technical concepts associated with the integration of OWFs. To help fill the gap, this article performs an in-depth investigation of existing alternating current fault ride through (ACFRT) techniques of modular multilevel converter-based high-voltage direct current (MMC-HVDC) for OWFs. These techniques include the use of AC/DC choppers, flywheel energy storage devices (FESDs), power reduction strategies for OWFs, and energy optimization of the MMC. This article covers both scenarios of onshore and offshore AC faults. Given the importance of wind turbines (WTs) in transforming wind energy into mechanical energy, this article also presents an overview of four WT topologies. In addition, this article explores the advanced converter topologies employed in HVDC systems to transform three-phase AC voltages to DC voltages and vice versa at each terminal of the DC link. Finally, this article explores the key stability and control concepts, such as small signal stability and large disturbance stability, followed by future research trends in the development of converter topologies for HVDC transmission such as hybrid HVDC systems, which combine current source converters (CSCs) and voltage source converters (VSCs) and diode rectifier-based HVDC (DR-HVDC) systems. Full article

According to the UNHCR, 117.2 million people have been displaced in 2023, with the rate and scale of displacement surpassing the resources available to assist those impacted. Modular construction is favored over traditional methods to meet the urgent demand for affordable housing as it overcomes challenges like long project timelines, high costs, and safety and environmental issues. However, manual assembly is often slow and prone to errors, resulting in inefficiencies and higher costs. While advanced technologies could improve the process, there is limited research on automating assembly in modular construction. This research aims to assess how automation affects the time efficiency and cost of the modular construction process, aiming to improve affordable housing production by automating modular construction. The research follows a quantitative approach, collecting data through simulation to evaluate the effectiveness of integrating robotics in modular construction assembly processes. It compares the performance of automated and manual assembly processes, focusing on resource utilization, time savings, and cost implications. The results reveal that modular manufacturing automated assembly offers faster assembly times and improved cost efficiency, leading to higher productivity and lower overall construction costs. By conducting a detailed analysis, this research provides insights that can guide the integration of automation into modular construction manufacturing. Full article

Due to the nature of construction work projects that must be executed outside regardless of the weather, and because it rains most of the time in the UK, the workforce will need dry clothing to work in the best conditions for their health and productivity. This study aims to identify the energy currently used in a drying room at the Everton site in Liverpool, based on which improvements will be made to optimise the drying system and garment hanging arrangement to reduce the energy bill and carbon (CO₂) emissions to the environment. A thermal model using IESVE 2023 (Integrated Environmental Solutions Virtual Environment) software was developed to predict the energy consumption in the current intensive energy drying room to know the baseline energy use before implementing energy savings by constructing a test drying room composed of a heater to raise the temperature, an air circulation fan to circulate air in the room, and a dehumidifier to reduce humidity. Moisture content in the garments to dry was monitored hourly from the 25th of April to the 2nd of May for seven hours, and the results show that the best drying system in terms of energy consumption to adopt is the combination of a dehumidifier and an air mover, saving about 60%. However, adding a low-energy heater to that will still realise the same savings—58%—and the drying process will be faster in this case. Based on this fact, it can be concluded that the impact of low humidity, good air velocity, and high temperature have a great impact on reducing energy consumption, drying time, and carbon emissions. Full article

Modular construction is emerging into the limelight in the construction industry as one of the front-running modern methods of construction, facilitating multiple benefits, including improved productivity. Meanwhile, Circular Economy (CE) principles are also becoming prominent in the Building Construction Industry (BCI), which is infamous for its prodigious resource consumption and waste generation. In essence, the basic concepts of modular construction and CE share some commonalities in their fundamental design principles, such as standardisation, simplification, prefabrication, and mobility. Hence, exploring ways of synergising circularity and modularity in the design stage with a Whole Life Cycle (WLC) of value creation and retention is beneficial. By conducting a thorough literature review, supported by expert interviews and brainstorming sessions, followed by a case study, the concept of Design for Circular Manufacturing and Assembly (DfCMA) was proposed to deliver circularity and modularity synergistically in circularity-oriented modular construction. This novel conceptualisation of DfCMA is envisaged to be a value-adding original theoretical contribution of this paper. Furthermore, the findings are expected to add value to the BCI by proposing a way forward to synergise circularity and modularity to contribute substantially towards an efficient circular built environment. Full article

One possible solution that mitigates the effects of climate change is the implementation of vertical greenery systems, which have the potential to reduce the need for cooling and provide energy savings for heating. This paper evaluates the effects of an innovative modular green wall on indoor temperature and energy use in a residential case study building. This research was carried out on a residential house in the city of Ghent, Belgium, whose southwest facade is covered with a specific type of modular green wall (a structure with a specific substrate and plants that have the ability to purify water so that it can be reused in the house). The monitoring process included four different temperatures (in front of and behind the green wall, in the substrate, and on the wall without greenery) during winter and summer periods. To analyze the effect on the internal temperature and energy use, a DesignBuilder simulation model was built and validated against these experimental results. This green wall has proven to have the greatest effect during the hottest summer days by reducing the indoor temperature by up to 3.5 °C. It also effectively increases the indoor temperature by up to 1.4 °C on a cold winter day, leading to energy savings of 6% on an annual basis. Full article

A significant challenge in utilizing hydrogen in conventional internal combustion engines is achieving a balance between NOx emissions and brake power output. A lean premixed charge (Lambda ≈ 2.5) allows for efficient and stable combustion with minimal NOx emissions. However, this comes at the cost of reduced power density due to the higher air requirements of the thermodynamic process. While supercharging can mitigate this drawback, it introduces increased complexity, cost, and size. An intriguing alternative is the 2-stroke cycle, particularly in an opposed piston (OP) configuration. This study presents the virtual development of a single-cylinder 2-stroke OP engine with a total displacement of 0.95 L, designed to deliver 25 kW at 3000 rpm. Thanks to its compact size, high thermal efficiency, robustness, modularity, and low manufacturing cost, this engine is intended for use either as an industrial power unit or in combination with electric motors in hybrid vehicles. The overarching goal of this project is to demonstrate that internal combustion engines can offer a practical and cost-effective alternative to hydrogen fuel cells without significant penalties in terms of efficiency and pollutant emissions. The design of this novel engine started from scratch, and both 1D and 3D CFD simulations were employed, with particular focus on optimizing the cylinder’s geometry and developing an efficient low-pressure injection system. The numerical methodology was based on state-of-the-art commercial codes, in line with established engineering practices. The numerical results indicated that the optimized engine configuration slightly surpasses the target performance, achieving 29 kW at 3000 rpm, while maintaining near-zero NOx emissions (<20 ppm) and high brake thermal efficiency (~40%) over a wide power range. Additionally, the cost of this engine is projected to be lower than an equivalent 4-stroke engine, due to fewer components (e.g., no cylinder head, poppet valves, or camshafts) and a lighter construction. Full article

This paper presents GraphPPL.jl, a novel probabilistic programming language designed for graphical models. GraphPPL.jl uniquely represents probabilistic models as factor graphs. A notable feature of GraphPPL.jl is its model nesting capability, which facilitates the creation of modular graphical models and significantly simplifies the development of large (hierarchical) graphical models. Furthermore, GraphPPL.jl offers a plugin system to incorporate inference-specific information into the graph, allowing integration with various well-known inference engines. To demonstrate this, GraphPPL.jl includes a flexible plugin to define a Constrained Bethe Free Energy minimization process, also known as variational inference. In particular, the Constrained Bethe Free Energy defined by GraphPPL.jl serves as a potential inference framework for numerous well-known inference backends, making it a versatile tool for diverse applications. This paper details the design and implementation of GraphPPL.jl, highlighting its power, expressiveness, and user-friendliness. It also emphasizes the clear separation between model definition and inference while providing developers with extensibility and customization options. This establishes GraphPPL.jl as a high-level user interface language that allows users to create complex graphical models without being burdened with the complexity of inference while allowing backend developers to easily adopt GraphPPL.jl as their frontend language. Full article

Background/Objectives: The study of oxidative stress in cells and ways to prevent it attract increasing attention. Antioxidant defense of cells can be activated by releasing the transcription factor Nrf2 from a complex with Keap1, its inhibitor protein. The aim of the work was to study the effect of the modular nanotransporter (MNT) carrying an R1 anti-Keap1 monobody (MNT_R1) on cell homeostasis. Methods: The murine hepatocyte AML12 cells were used for the study. The interaction of fluorescently labeled MNT_R1 with Keap1 fused to hrGFP was studied using the Fluorescence-Lifetime Imaging Microscopy–Förster Resonance Energy Transfer (FLIM-FRET) technique on living AML12 cells transfected with the Keap1-hrGFP gene. The release of Nrf2 from the complex with Keap1 and its levels in the cytoplasm and nuclei of the AML12 cells were examined using a cellular thermal shift assay (CETSA) and confocal laser scanning microscopy, respectively. The effect of MNT on the formation of reactive oxygen species was studied by flow cytometry using 6-carboxy-2′,7′-dichlorodihydrofluorescein diacetate. Results: MNT_R1 is able to interact with Keap1 in the cytoplasm, leading to the release of Nrf2 from the complex with Keap1 and a rapid rise in Nrf2 levels both in the cytoplasm and nuclei, ultimately causing protection of cells from the action of hydrogen peroxide. The possibility of cleavage of the monobody in endosomes leads to an increase in the observed effects. Conclusions: These findings open up a new approach to specifically modulating the interaction of intracellular proteins, as demonstrated by the example of the Keap1-Nrf2 system. Full article

Landscape maintenance is essential for ensuring agricultural productivity, promoting sustainable land use, and preserving soil and ecosystem health. Pruning is a labor-intensive task among landscaping applications that often involves repetitive pruning operations. To address these limitations, this paper presents the development of a dual-arm holonomic robot (called the KOALA robot) for precision plant pruning. The robot utilizes a cross-functionality sensor fusion approach, combining light detection and ranging (LiDAR) sensor and depth camera data for plant recognition and isolating the data points that require pruning. The You Only Look Once v8 (YOLOv8) object detection model powers the plant detection algorithm, achieving a 98.5% pruning plant detection rate and a 95% pruning accuracy using camera, depth sensor, and LiDAR data. The fused data allows the robot to identify the target boxwood plants, assess the density of the pruning area, and optimize the pruning path. The robot operates at a pruning speed of 10–50 cm/s and has a maximum robot travel speed of 0.5 m/s, with the ability to perform up to 4 h of pruning. The robot’s base can lift 400 kg, ensuring stability and versatility for multiple applications. The findings demonstrate the robot’s potential to significantly enhance efficiency, reduce labor requirements, and improve landscape maintenance precision compared to those of traditional manual methods. This paves the way for further advancements in automating repetitive tasks within landscaping applications. Full article

Vesicular stomatitis virus (VSV) is a prototype RNA virus that has been instrumental in advancing our understanding of viral molecular biology and has applications in vaccine development, cancer therapy, antiviral screening, and more. Current VSV genome plasmids for purchase or contract virus services provide limited options for modification, restricted to predefined cloning sites and insert locations. Improved methods and tools to engineer VSV will unlock further insights into long-standing virology questions and new opportunities for innovative therapies. Here, we report the design and construction of a full-length VSV genome. The 11,161 base pair synthetic VSV (synVSV) was assembled from four modularized DNA fragments. Following rescue and titration, phenotypic analysis showed no significant differences between natural and synthetic viruses. To demonstrate the utility of a synthetic virology platform, we then engineered VSV with a foreign glycoprotein, a common use case for studying viral entry and developing anti-virals. To show the freedom of design afforded by this platform, we then modified the genome of VSV by rearranging the gene order, switching the positions of VSV-P and VSV-M genes. This work represents a significant technical advance, providing a flexible, cost-efficient platform for the rapid construction of VSV genomes, facilitating the development of innovative therapies. Full article

The intricate structure of human hands requires personalized orthotic treatments, especially with the growing aging population’s demand for accessible care. While traditional orthoses are effective, they face challenges of cost, customization time, and accessibility. Additive manufacturing, particularly material extrusion (MEX) techniques, can effectively address challenges in orthotic device production by enabling automated, complex, and cost-effective solutions. This work aims to provide engineers with a comprehensive set of design considerations for developing hand orthoses using MEX technology, focusing on applying design for additive manufacturing principles, to enhance rehabilitation outcomes. This objective is achieved by establishing design requirements for hand orthoses, reviewing design choices and methodologies across conventional and state-of-the-art MEX-based devices, and proposing an innovative approach to orthotic design. Hand orthosis design requirements were gathered through workshops with occupational therapists and categorized into engineer-, medical-, and patient-specific needs. A review of 3D-printed hand orthoses using MEX analyzes various design approaches, providing insights into existing solutions. The study introduces a modular design concept aimed at improving rehabilitation by enhancing customizability and functionality. It highlights the potential of MEX for creating personalized, cost-effective orthoses and offers recommendations for future research, to optimize designs and improve patient outcomes. Full article

‘Rhythmite’, Ca₂₉(SiO₄)₈Cl₂₆, an anthropogenic calcium chloride silicate from the Chelyabinsk coal basin (South Ural, Russia), was investigated using chemical microprobe analysis, in situ single-crystal X-ray diffraction analysis (27–727 °C), and Raman spectroscopy. ‘Rhythmite’ is orthorhombic, Pnma: a = 17.0749(6), b = 15.1029(5), c = 13.2907(4) Å, and V = 3427.42(18) ų (R₁ = 0.045). The crystal structure of ‘rhythmite’ consists of a porous framework formed by Ca-O bonds and SiO₄ tetrahedra with additional Ca²⁺ cations and Cl⁻ anions in the structure interstices. The framework is built up from multinuclear [Ca₁₅(SiO₄)₄]¹⁴⁺ fundamental building blocks (FBBs) cut from the crystal structure of α-Ca₃SiO₄Cl₂ (‘albovite’). The FBBs are linked by sharing common Ca atoms to form a network with an overall pcu topology. The empirical chemical formula was calculated as Ca_29.02(Si_7.89Al_0.05P_0.05)_Ʃ7.99O₃₂Cl₂₆ (on the basis of Cl + O = 58). ‘Rhythmite’ is stable up to 627 °C and expands slightly anisotropically (α_max/α_min = 1.40) in the ab and bc planes and almost isotropically in the ac plane (α₃₃/α₁₁ = 1.02) with the following thermal expansion coefficients (×10⁶ °C⁻¹): α₁₁ = 14.6(1), α₂₂ = 20.5(4), α₃₃ = 15.0(3), and α_V = 50.1(6) (room temperature). During expansion, the silicate tetrahedra remain relatively rigid with average bond length changes of less than 0.5%. A structural complexity analysis indicates that ‘rhythmite’ is complex, with I_G,total = 920.313 (bits/u.c.), which significantly exceeds the average value of structural complexity for silicates and is caused by the modular framework construction and the presence of a large number of independent positions in the crystal structure. Full article

Modular design facilitates easy disassembly and reduces the manufacturer’s remanufacturing costs. However, the simplicity and modular structure of products can intensify competition between manufacturers and third-party recyclers. To improve recovery efficiency, this study examines the impact of modular design on the manufacturer’s selection of recovery strategies, including centralized, cooperation, and competition strategies. We examine the optimal recovery strategy for achieving both economic goals, such as supply chain profit, and environmental goals, such as collection quantity. Our results indicate that the manufacturer should adopt cooperation recovery and invest in higher modularity when faced with strong competition from third-party recyclers. Conversely, when the competitiveness of third-party recovery is relatively low, a competition recovery strategy is more advantageous. Contrary to conventional wisdom, which suggests limiting product disassembly to reduce third-party recovery competitiveness, our results indicate that manufacturers should invest in higher modularity and avoid engaging in price wars to prevent third-party entry. Moreover, competition recovery leads to a higher collection quantity, while cooperation recovery is preferred in terms of supply chain profit. This study provides theoretical guidance for manufacturers in selecting optimal recovery strategies and offers recommendations for governments on regulating product disassembly effectively. Full article