Design Strategies Research Articles

Device-based 24-hour movement behaviours in adult phase III cardiac rehabilitation service-users during the COVID-19 pandemic: a mixed-methods prospective observational study

Purpose To examine changes in device-based 24-hour movement behaviours (MB), and facilitators and barriers to physical activity (PA) and exercise, during remotely-delivered cardiac rehabilitation (RDCR). Materials and methods This prospective observational study used wrist-worn GENEActiv accelerometers to assess MB of 10 service-users (63 ± 10 years) at the start, middle, and end of three-months of RDCR. Barriers and facilitators to PA and exercise were explored through self-report diaries and analysed using content analysis. Results At start, service-users were sedentary for 12.6 ± 0.7 h · day−1 and accumulated most PA at a light-intensity (133.52 ± 28.57 min · day−1) – neither changed significantly during RDCR. Sleep efficiency significantly reduced from start (88.80 ± 4.2%) to the end (86.1 ± 4.76%) of CR, with values meeting health-based recommendations (≥85%). Barriers to RDCR exercise included exertional discomfort and cardiac symptoms, and reduced confidence when exercising alone. Setting meaningful PA goals, self-monitoring health targets, and having social support, facilitated PA and exercise during RDCR. Conclusions Our RDCR programme failed to elicit significant changes in MB or sleep. To increase the likelihood of successful RDCR, it is important to promote a variety of exercise and PA options, target sedentary time, and apply theory to RDCR design, delivery, and support strategies.

Targeting Solvent-Front Mutations for Kinase Drug Discovery: From Structural Basis to Design Strategies.

Solvent-front mutations have emerged as a common mechanism leading to acquired resistance to kinase inhibitors, representing a major challenge in the clinic. Several new-generation kinase inhibitors targeting solvent-front mutations have either been approved or advanced to clinical trials. However, there remains a need to discover effective, new-generation inhibitors. In this Perspective, we systematically summarize the general types of solvent-front mutations across the kinome and describe the development of inhibitors targeting some key solvent-front mutations. Additionally, we highlight the challenges and opportunities for the next generation of kinase inhibitors directed toward overcoming solvent-front mutations.

Optimal prototype filter design in GFDM systems for self-interference elimination: A novel signal processing approach

We present an innovative conceptual framework and a comprehensive mathematical model to advance the understanding and mitigation of self-interference phenomena within generalized frequency division multiplexing (GFDM). By introducing a novel analytical perspective, we decompose the self-interference effects inherent to GFDM into two orthogonal constituents through a vectorized representation. Our elucidation of the self-interference components in terms of prototype filter parameters in the frequency domain is of particular significance. This theoretical characterization allows us to derive explicit analytical expressions, thereby paving the way for the proposition of an optimal filter design strategy that effectively mitigates self-interference distortions within GFDM systems. Our investigation reveals a noteworthy linkage between the required bandwidth allocation for individual subcarriers and the sub-symbol configuration within the proposed optimal prototype filter. This relationship underscores the filter’s adeptness in optimizing spectrum utilization across the system. Through an analytical examination of the bit error rate (BER) performance within the GFDM framework, we establish the superior efficacy of our proposed optimal filter design relative to contemporary approaches documented in extant literature. Validation of our analytical findings is conducted via meticulous computer simulations, where a strong concurrence between the analytical predictions and the observed simulation outcomes is manifest.

Design Strategies for High Performance of Proton Exchange Fuel Cells with Ti‐Sputtered Carbon Nanotube Sheet Functional Layer

Design Strategies for High Performance of Proton Exchange Fuel Cells with Ti‐Sputtered Carbon Nanotube Sheet Functional Layer

Sequential thermomechanical stress and cracking analysis of photovoltaic modules with full and half-cut cells

The transition from conventional full-cell patterns to half-cell modules in the photovoltaic (PV) industry promises enhanced stability and efficiency. This study investigates the thermomechanical behaviour and stress distribution within half-cell and full-cell PV modules during the manufacturing and operational phases. Using finite element modeling, the research simulates sequentially the manufacturing and operating processes such as laser cutting, soldering, lamination, mechanical loading and thermal cycling. The Extended Finite Element Method (XFEM) predicts crack initiation and propagation in the crack-sensitive regions in PV modules during their entire life. Key findings highlight stress concentrations during manufacturing, influenced by parameters like laser power, scribing length and Silicon wafer size. Mechanical loading (ML) and thermal cycling (TC) induce additional stresses, impacting module reliability. The results are useful for the optimization of material properties and the development of advanced design strategies contributing to the durability and efficiency of PV systems.

Topography control and component design strategies to enhance electrochemical performance of O3-Type cathode materials for Sodium-ion batteries

Layered transition metal oxides (NaxTMO2, 0 < x ≤ 1) are considered one of the most promising cathodes for Sodium-ion batteries (SIBs) due to their high theoretical capacity and operability. However, NaxTMO2 still faces significant challenges, including poor kinetic performance and low energy efficiency. Herein, in order to enhance the kinetics of NaNi1/3Fe1/3Mn1/3O2 (NaNFMO), topography control and component design were proposed: First, Cu doping (Cu-NaNFMO) was used to expand lattice channels and improve “flat sheet” of layered oxide, which synergistically enhanced transport kinetics of Na+. Second, Co coating (NaNFMO@Co) reacted with surface residue to form a fast-ionic conductor NaxCoO2 (0 < x ≤ 1), which inhibited interfacial side reactions and enhanced transport kinetics of Na+. Furthermore, the presence of strong Cu-O bonds in Cu-NaNFMO and fast-ionic conductor NaxCoO2 in NaNFMO@Co led to better electrochemical redox performance, the initial charge specific capacity of NaNFMO was increased from 141.5 mAh g⁻1 to 145.8 mAh g⁻1 and 144 mAh g⁻1, with capacity retention improving by nearly 10 % after 100 cycles. Furthermore, NaNFMO@Co improves ICE from 90.56 % to 93.57 %. With the improved kinetics, the DCR of pouch cells decreased, and the energy efficiency increased from 93.3 % to 94 % and 95.7 %.

Co-Designing Digital Health Intervention for Monitoring Medication and Consultation Among Transgender People in Underserved Communities: Collaborative Approach.

In many parts of the world, men who have sex with men and transgender individuals face criminalization and discrimination. As a result, they are less likely to seek medical help, despite experiencing higher rates of HIV/AIDS, mental health issues, and other health problems. Reaching key populations (KPs) with essential testing, care, and treatment services can be challenging, as they often have a higher likelihood of contracting and spreading the virus. They have limited access to antiretroviral (ARV) therapy (ART) services, which means that KPs may continue to serve as reservoirs for new HIV infections if they do not receive effective HIV programming. This ongoing issue complicates efforts to control the epidemic. Therefore, modeling a digital health system to track ARV medication access and use is crucial. This paper advocates for the use of digital interventions to manage the health of KPs in underserved regions, using Nigeria as a case study. This study aims to assess digital health interventions for monitoring medication and consultations among transgender people in underserved communities. It also sought to determine whether a system exists that could support ART adherence in Nigeria. Additionally, the study evaluated design strategies to address privacy and confidentiality concerns, aiming to reduce nonadherence to ARV medications among KPs in Nigeria. A qualitative approach was adopted for this research, involving a thematic analysis of information collected from interviews with clinicians and other health practitioners who work directly with these communities, as well as from an interactive (virtual) workshop. The findings from the thematic analysis indicate a need to increase attendance at ART therapy sessions through the implementation of an intensive care web app. Unlike previous solutions, this study highlights the importance of incorporating a reminder feature that integrates with an in-app telemedicine consultancy platform. This platform would facilitate discussions about client challenges, such as adverse drug effects, counseling sessions with clinical psychologists, and the impact of identity discrimination on mental health. Other data-driven health needs identified in the study are unique drug request nodes, client-led viral load calculators, remote requests, and drug delivery features within the web app. Participants also emphasized the importance of monitoring medication compliance and incorporating user feedback mechanisms, such as ratings and encouragement symbols (eg, stars, checkmarks), to motivate adherence. The study concludes that technology-driven solutions could enhance ART adherence and reduce HIV transmission among transgender people. It also recommends that local governments and international organizations collaborate and invest in health management services that prioritize health needs over identity.

Enhancing strength-conductivity synergy in an ultrathin lamellar-structured W[sbnd]Cu composite prepared by freeze-casting and infiltration

One of the key strategies to enhance the performance of composites is the implementation of a lamellar structure, which has demonstrated remarkable success. In this study, an ultrathin lamellar WCu composite was fabricated using a combination of freeze-casting and infiltration techniques. Compared to the homogeneous WCu composite, the aligned structure in this composite provides continuous conductive channels for electrons, reducing interface scattering. Additionally, the ultrathin lamellae offer exceptional load-bearing capacity. These synergistic effects result in both superior strength and enhanced electrical conductivity. This innovative design strategy for WCu composites presents promising potential for advancing the development of next-generation composite materials.

Flammability and thermal analysis of vertically oriented polyvinyl alcohol/DOPO derivative/MXene composite aerogel

The fabrication of ultralight high-performance flame-retardant composites significantly reduces fire risk for buildings. Flame retardation of porous polyvinyl alcohol (PVA) aerogels with directional arrangement is difficult. Herein, the polyvinyl alcohol/ 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide derivative/two-dimensional (2D) MXene (PVA/DiDOPO/MXene) composite aerogel was prepared by ice template one-way freezing process. PVA-DiDOPO4 composite aerogel with an oriented porous structure reaches the V-1 level at the UL-94 test. Moreover, the peak heat release rate (pHRR) value of PVA-DiDOPO4 reduces to 452.26 (W/g) from 482.88 (W/g) of pure PVA. In addition, PVA/DiDOPO/MXene composite aerogel has improved thermal decomposition properties such as the maximum decomposition temperature (Tmax1) of the PVA-DiDOPO4 sample attains 319.92 °C from pure PVA of 302.90 °C. The design strategy of PVA combined 2D MXene nanosheet and DOPO derivatives construct oriented porous composite aerogel paves the way for the fabrication and customization of ultralight flame-retardant polymer composites, which can be expected to be applied in construction and reduce fire risk.

Unraveling Lewis acid-base sites in defected MOFs for catalyzing dicyclopentadiene hydrogenation via a DFT study and descriptor exploration

The 12-connected UiO-66 MOFs with great defect regulation ability have attracted significant attention due to the easily tunable electronic structure and surface electrostatic potential distribution of metal nodes. In this density functional theory (DFT) study, we systematically explored the effect of bi-active site types as the frustrated Lewis pair (FLP) and classical Lewis pair (LP) as well as metal elements of secondary building units (SBUs) on the catalytic hydrogenation of dicyclopentadiene (DCPD) to tetrahydrodicyclopentadiene (THDCPD). These design strategies effectively modulate the frontier molecular orbital energy level that determines the binding strength between MOFs and adsorbed species *Hδ+-Hδ- and charges transfer before and after H2 chemisorption. We also found that the heterolytic H2 adsorption energy and charges transfer linearly correlate with the energy barrier. In order to unravel the clear-cut designing strategies and further simplify computational complexity, we firstly proposed the ADCH charges difference between the Lewis acid and the Lewis base centers (ΔQM-O) as an intrinsic descriptor for catalytic activity of DCPD into THDCPD, which can effectively describe the reactivity and electrostatic effects of oppositely charged bi-active sites in the system. Furthermore, the defective UiO-66(Ce) MOF with moderate ΔQM-O effectively balance the contradiction between the barriers of two primitive reaction: the heterolytically H2 dissociation to *Hδ+-*Hδ- and the desorption of the active hydrogen species to hydrogenate 8,9-dihydrodicyclopentadiene (8,9-DHDCPD), resulting in the optimal catalytic performance. This work provides a deep understanding of the catalytic mechanism of MOFs with multiple active sites and might open up avenues for the rational design of novel hydrogenation catalysts.

DNA Mechanics: From Single Stranded to Self-Assembled.

DNA encodes genetic information and forms various structural conformations with distinct physical, chemical, and biological properties. Over the past 30 years, advancements in force manipulation technology have enabled the precise manipulation of DNA at nanometer and piconewton resolutions. This mini-review discusses these force manipulation techniques for exploring the mechanical properties of DNA at the single-molecule level. We summarize the distinct mechanical features of different DNA forms while considering the impact of the force geometry. We highlight the role of DNA mechanics in origami structures that serve as self-assembled building blocks or mechanically responsive/active nanomachines. Accordingly, we emphasize how DNA mechanics are integral to the functionality of origami structures for achieving mechanical capabilities. Finally, we provide an outlook on the intrinsic mechanical properties of DNA, from single stranded to self-assembled higher-dimensional structures. This understanding is expected to inspire new design strategies in DNA mechanics, paving the way for innovative applications and technologies.

Overcoming strength-ductility and functional period-degradability tradeoffs: Multifunctional biodegradable polyesters with ionic cluster skeleton and PDMS skin

To overcome the strength-ductility and functional period-degradability tradeoffs of biodegradable polyesters, we proposed a nanophase structure design strategy to construct a soft-hard dual phase in poly(butylene succinate) (PBS) copolymers by simultaneously introducing polydimethylsiloxane (PDMS) and isophthalate-5-sulfonate (SIPM) on PBS macromolecular chains to improve the stiffness, toughness, and multifunctionality. The high-resolution transmission electron microscope (HR-TEM) and energy dispersive X-Ray spectroscopy (EDX) tests indicated that PBS copolymers possessed continuous “ionic cluster skeleton” and “PDMS skin”. The hybrid liquid state theory and self-consistent field approach for copolymers further demonstrated the mechanism of microphase separation for PDMS blocks and SIPM segments. The copolymers showed excellent yield strength of 52 MPa, great impact strength of 171 J/m, large extensibility of 491 %, and long functional period in the acidic environment. The novel stereo nanostructure endowed the materials with advanced multifunctions that can be applied in various applications, such as the biomedical field and flexible electronic devices. Compared with PBS, copolymers possessed excellent in vitro attachment and proliferation of MC3T3-E1 cells. Furthermore, the synergistic effect of the ionic skeleton and PDMS skin improved the ionic conductivity of the materials. The copolymer film was innovatively employed as anion-exchanging separators of supercapacitors with acid-organized electrolytes. It has been testified that this newly designed strategy of a novel stereo nanophase structure was efficient in endowing the biodegradable polyesters with excellent combined properties and multifunctions.

A Comparative Analysis of Computational Strategies in Multi-Epitope Vaccine Design Against Human Papillomavirus and Cervical Cancer.

Given the critical role of human papillomavirus (HPV) in the cause of cervical cancer and other malignancies, there is a need for innovative approaches to preventing this infection. It has been shown that immunoinformatics is an important strategy in computational vaccinology. It is used to design new multi-epitope vaccines against different types of HPV and subsequent cervical cancer. This paper reviews the scope of the entire computational pipeline of HPV vaccine design, starting from data analysis at the genomic and proteomic levels and continuing to epitope predictions of the innate and adaptive immune systems. The search strategy was based on investigating original articles published in "Google Scholar" and "PubMed" from 2015 to 2023-2024. The terms "Immunoinformatics", "Bioinformatics", "Human papillomavirus (HPV)", "Vaccine design", "In silico vaccine design", "Multi-epitope vaccine design", "Vaccinology" and "HPV vaccine" were used to for this purpose. We discussed various essential tools involved in the computational design of the vaccine process, e.g., sequence analysis, epitope prediction, conservancy analysis, tertiary structure modeling, refinement, molecular docking, molecular dynamics (MD) simulation, and in silico cloning. This review article describes immunoinformatics methods that facilitate the design of a multi-epitope vaccine against HPV. However, this pipeline can also be used to design novel chimeric vaccines for other pathogens.

RSSR Mechanism Design and Motion Control Strategy of a Carbon-Free Vehicle for Obstacle Avoidance Competition

RSSR Mechanism Design and Motion Control Strategy of a Carbon-Free Vehicle for Obstacle Avoidance Competition

Facile fabrication of graphene aerogel/Cu/CuO for enhanced sodium storage performance

It is widely recognized that CuO experiences volume expansion and conductivity issues, leading to unsatisfactory performance in sodium-ion batteries. A feasible approach to mitigate these challenges is the combination of Cu/CuO nanosheets with porous reduced graphene oxide aerogel (GA). In this study, an innovative composite of Cu/CuO nanosheets encapsulated within a 3D GA structure (GA/Cu/CuO) was synthesized via an alkaline exfoliation-mild self-assembly method. The results reveal that the Na+ storage properties of Cu/CuO/GA significantly surpassed those of pure CuO. Specifically, the GA/Cu/CuO exhibited a capacity retention of 320 mAh g–1 after 220 cycles at a current density of 0.1 A g–1, and demonstrated an optimized rate capability of 225 mAh g–1 at a current density of 1 A g–1. The enhanced rate and long-cycle performances are attributed to the synergistic effects of Cu/CuO nanosheets and porous GA, which shorten the Na+ transfer pathway, improve electronic/ionic conductivity, and buffer volume expansion during the discharge/charge process. Furthermore, the facile and innovative design strategy presented could be applicable to the synthesis of other composites for energy storage applications.

Dual-Mechanism Design Strategy for High-Efficiency and Long-Lived Organic Afterglow Materials.

Organic room-temperature phosphorescence (RTP) and afterglow materials hold great potential for various applications, but there remain inherent trade-offs between the afterglow efficiency and the lifetime. Here, we propose a dual-mechanism design strategy, leveraging the RTP or thermally activated delayed fluorescence (TADF) mechanism for a high afterglow efficiency and the organic long-persistent luminescence (OLPL) mechanism for a prolonged afterglow duration. The intramolecular charge transfer (ICT)-type difluoroboron β-diketonate molecules with a large S1 dipole moment are doped as the luminescent component into the organic matrix with a large dipole moment, and a series of TADF-type afterglow materials can be achieved with an afterglow efficiency of up to 88.7% and an afterglow lifetime of 200 ms. To prolong the afterglow duration, an electron donor is introduced as the third component to generate traps and facilitate charge separation. The obtained materials exhibit a dual afterglow mechanism, first exhibiting a TADF/RTP afterglow with an afterglow efficiency of up to 50.9%, followed by an hours-long OLPL afterglow emission with an afterglow efficiency of up to 13.1%. Further investigations reveal that an appropriate heavy-atom effect can facilitate the intersystem crossing process, which can promote the charge separation process and thus improve the OLPL afterglow performance. Additionally, rare-earth upconversion materials are introduced into OLPL materials to enable their near-infrared excitation properties, showcasing their potential applications in bioimaging.

Smart Safety Design for Evacuation Signs in Large Space Buildings Based on Height Setting and Visual Range of Evacuation Signs

In case of emergency, evacuation signs play an important role in guiding people to evacuate safety exits in large space buildings. Large space buildings are characterized by high ceilings and large areas. In the existing legislation and standards, the height setting of evacuation signs is fixed, but the influence of height changes on the visibility of evacuation signs is very important. This study fully considers the relationship between the height setting change of evacuation signs and the visual range and puts forward a smart safety design strategy for evacuation signs. The smart safety design consists of two parts, one is the mathematical relationship between the height change of evacuation signs and the visual range of personnel, and the other is the integration of the application process of smart devices. Firstly, the visual range of two different sizes of evacuation signs placed at the height of 1.7 to 6 m was measured experimentally in China. The results showed that: (1) with an increase in the height of the evacuation signs, their viewing distance gradually decreased and the visual range was reduced; (2) the mathematical model of the change between the height and the visual range of evacuation signs was established; (3) the height of evacuation signs between 3 to 5 m agreed more with the visual habits of the people. Then, on this basis, the smart safety design method can use related mathematical models to set the evacuation signs at the optimal height based on the actual distance between people and evacuation signs, ensuring that people can see the signs the first time, thus providing evacuation guidance for evacuees and improving the safety of large space buildings.

Atomic-level design of biomimetic iron-sulfur clusters for biocatalysis.

Designing biomimetic materials with high activity and customized biological functions by mimicking the central structure of biomolecules has become an important avenue for the development of medical materials. As an essential electron carrier, the iron-sulfur (Fe-S) clusters have the advantages of simple structure and high electron transport capacity. To rationally design and accurately construct functional materials, it is crucial to clarify the electronic structure and conformational relationships of Fe-S clusters. However, due to the complex catalytic mechanism and synthetic process in vitro, it is hard to reveal the structure-activity relationship of Fe-S clusters accurately. This review introduces the main structural types of Fe-S clusters and their catalytic mechanisms first. Then, several typical structural design strategies of biomimetic Fe-S clusters are systematically introduced. Furthermore, the development of Fe-S clusters in the biocatalytic field is enumerated, including tumor treatment, antibacterial, virus inhibition and plant photoprotection. Finally, the problems and development directions of Fe-S clusters are summarized. This review aims to guide people to accurately understand and regulate the electronic structure of Fe-S at the atomic level, which is of great significance for designing biomimetic materials with specific functions and expanding their applications in biocatalysis.

Ultrahigh Energy Storage in (Ag,Sm)(Nb,Ta)O3 Ceramics with a Stable Antiferroelectric Phase, Low Domain-Switching Barriers, and a High Breakdown Strength.

AgNbO3 (AN) antiferroelectrics (AFEs) are regarded as a promising candidate for high-property dielectric capacitors on account of their high maximum polarization, double polarization-electric field (P-E) loop characteristics, and environmental friendliness. However, high remnant polarization (Pr) and large polarization hysteresis loss from room-temperature ferrielectric behavior of AN and low breakdown strength (Eb) cause small recoverable energy density (Wrec) and efficiency (η). To solve these issues, herein, we have designed Sm3+ and Ta5+ co-doped AgNbO3. The addition of Sm3+ and Ta5+ reduces the tolerance factor, polarizability of B-site cations, and domain-switching barriers, enhancing AFE phase stability and decreasing hysteresis loss. Meanwhile, adding Sm3+ and Ta5+ leads to decreased grain sizes, increased band gap, and reduced leakage current, all contributing to increased Eb. As a benefit from the above synergistic effects, a high Wrec of 7.24 J/cm3, η of 72.55%, power density of 173.73 MW/cm3, and quick discharge rate of 18.4 ns, surpassing those of many lead-free ceramics, are obtained in the (Ag0.91Sm0.03)(Nb0.85Ta0.15)O3 ceramic. Finite element simulations for the breakdown path and transmission electron microscopy measurements of domains verify the rationality of the design strategy.

Efficient thermally activated delayed fluorescence materials from symmetric anthraquinone derivatives for high-performance red OLEDs

Constructing efficient red thermally activated delayed-fluorescence (TADF) materials for high-performance organic light-emitting diodes (OLEDs) remains challenging due to the formidable barrier of energy gap law. In this work, a design strategy of connecting two donor units to the adjacent positions of electron acceptor is proposed for creating red luminescent materials, and four Y-shaped TADF molecules consisting of strong electron-withdrawing anthraquinone (AQ) acceptor and triphenylamine or acridine-based donors are designed and synthesized. They exhibit strong red emissions (604−618 nm) in toluene solutions and orange/red emissions (566−608 nm) with good photoluminescence quantum yields (43−68%) in doped films, and enjoy small singlet-triplet energy gaps (0.02−0.10 eV) and fast reverse intersystem crossing processes (1.5–7.3 × 105 s−1), which are attributed to the unique Y-shape structure. A maximum external quantum efficiency of 19.5% with an electroluminescence peak at 616 nm is achieved for AQ-PTPA-based red doped device, representing the highest level for red TADF-OLEDs based on AQ acceptor in the literature. This work can provide guidance for the design of efficient red delayed-fluorescence molecules for the application in OLEDs.