Design Strategies Research Articles

Understanding the Changes in Brain Activation When Viewing Products with Differences in Attractiveness

Product design and attractiveness are pivotal factors that determine people’s positive reactions when viewing a product and may eventually affect their purchasing choices. Comprehending how people assess product design is crucial. Various studies have explored the link between product attractiveness and consumer behavior, but these were predominantly behavioral studies that offered limited insight into the neural processes underlying perceptions of product attractiveness. Gaining a deeper understanding of these neural mechanisms is valuable, as it enables the formulation of more objective design guidelines based on brain activity, enhancing product appeal and, ultimately, spurring consumer purchases. In our study, we sought to (1) elucidate the neural network engaged when individuals evaluate highly attractive product images, (2) delineate the neural network activated during the evaluation of less attractive product images, and (3) contrast the differences in neural networks between evaluations of highly and less attractive images. We utilized fMRI to investigate the neural activation patterns elicited by viewing product images of varying attractiveness levels. The results indicated distinct neural activations in response to the two types of attractive images. Highly attractive product images elicited activity in the anterior cingulate cortex (ACC) and the occipital pole, whereas less attractive product images stimulated the insula and the inferior frontal gyrus (IFG). The findings of this project provide some of the first insights of its kind and valuable insights for future product design, suggesting that incorporating more positive and rewarding elements could enhance product appeal. This research elucidates the neural correlates of people’s responses to product attractiveness, revealing that highly attractive designs activate reward-related brain regions, while less attractive designs engage areas associated with emotional processing. These findings offer a neuroscientific basis for further studies on developing design strategies that align with consumers’ innate preferences, potentially transforming product design and marketing practices. By leveraging this knowledge, designers can craft products that not only meet functional needs but also resonate more deeply on an esthetic level, thereby enhancing consumer engagement and purchase likelihood.

Robust Sandwich-Structured Thermally Activated Delayed Fluorescence Molecules Utilizing 11,12-Dihydroindolo[2,3-a]carbazole as Bridge.

Constructing folded molecular structures is emerging as a promising strategy to develop efficient thermally activated delayed fluorescence (TADF) materials. Most folded TADF materials have V-shaped configurations formed by donors and acceptors linked on carbazole or fluorene bridges. In this work, a facile molecular design strategy is proposed for exploring sandwich-structured molecules, and a series of novel and robust TADF materials with regular U-shaped sandwich conformations are constructed by using 11,12-dihydroindolo[2,3-a]carbazole as bridge, xanthone as acceptor, and dibenzothiophene, dibenzofuran, 9-phenylcarbazole and indolo[3,2,1-JK]carbazole as donors. They hold outstanding thermal stability with ultrahigh decomposition temperatures (556-563 oC), and exhibit fast delayed fluorescence and excellent photoluminescence quantum efficiencies (86%-97%). The regular and close stacking of acceptor and donors results in rigidified molecular structures with efficient through-space interaction, which are conducive to suppressing intramolecular motion and reducing reorganized excited-state energy. The organic light-emitting diodes (OLEDs) using them as emitters exhibit excellent electroluminescence performances, with maximum external quantum efficiencies of up to 30.6%, which is a leading value for the OLEDs based on folded TADF emitters. These results demonstrate the proposed strategy of employing 11,12-dihydroindolo[2,3-a]carbazole as bridge for planar donors and acceptors to construct efficient folded TADF materials is applicable.

Understanding Biases in ChatGPT-based Recommender Systems: Provider Fairness, Temporal Stability, and Recency

This paper explores the biases inherent in ChatGPT-based recommender systems, focusing on provider fairness (item-side fairness). Through extensive experiments and over a thousand API calls, we investigate the impact of prompt design strategies—including structure, system role, and intent—on evaluation metrics such as provider fairness, catalog coverage, temporal stability, and recency. The first experiment examines these strategies in classical top-K recommendations, while the second evaluates sequential in-context learning (ICL ). In the first experiment, we assess seven distinct prompt scenarios on top-K recommendation accuracy and fairness. Accuracy-oriented prompts, like Simple and Chain-of-Thought (COT), outperform diversification prompts, which, despite enhancing temporal freshness, reduce accuracy by up to 50%. Embedding fairness into system roles, such as “act as a fair recommender”, proved more effective than fairness directives within prompts. We also found that diversification prompts led to recommending newer movies, offering broader genre distribution compared to traditional collaborative filtering (CF) models. The system showed high consistency across multiple runs. The second experiment explores sequential ICL, comparing zero-shot and few-shot learning scenarios. Results indicate that including user demographic information in prompts affects model biases and stereotypes. However, ICL did not consistently improve item fairness and catalog coverage over zero-shot learning. Zero-shot learning achieved higher NDCG and coverage, while ICL-2 showed slight improvements in hit rate (HR) when age-group context was included. Overall, our study provides insights into biases of RecLLMs, particularly in provider fairness and catalog coverage. By examining prompt design, learning strategies, and system roles, we highlight the potential and challenges of integrating large language models into recommendation systems, paving the way for future research. Further details can be found at https://github.com/yasdel/Benchmark_RecLLM_Fairness.

Kesterite‐Type Narrow Bandgap Piezoelectric Catalysts for Highly Efficient Piezocatalytic Fenton System

AbstractPiezocatalytic Fenton (PF) system emerges as a promising approach to wastewater treatment by leveraging piezocatalysis to enhance Fenton‐like reactions. However, conventional piezocatalysts encounter challenges because they often compromise catalytic properties in biased favor of superior piezoelectricity, resulting in sluggish catalytic kinetics. To tackle this trade‐off, here a novel class of kesterite‐type narrow bandgap piezoelectrics, Cu2XSnS4 (CXTS, X = Zn, Ni, Co), is developed for PF reactions, which exhibit a unique combination of physicochemical attributes favorable for catalysis such as narrow bandgap (1.2–1.5 eV), high free charge density (1 × 1018 cm−3), mobility, and redox activity while retaining excellent piezoelectricity (62–142 pm V−1). With the well‐balanced piezoelectric, semiconducting, and catalytic properties, CXTS‐based PF systems demonstrate outstanding performance for tetracycline degradation, delivering a notable reaction kinetics of 0.34 min−1 only with a minor H2O2 dosage (1.2 mm), outperforming most of the conventional Fenton‐like reactions requiring a large amount H2O2 dosage by a factor up to 10. Such a remarkable performance is fulfilled by the simultaneously effective H2O2 activation and in situ generation of reactive oxygen species from oxygen and water via piezocatalysis. Additionally, the distinctive hierarchical morphology consisting of 2D nanosheets enables easy crystal domain deformation to trigger the piezoelectric effect, thereby drastically reducing the mechanical energy input required to drive redox reactions. Rigorous testing has validated the viability and practical feasibility of this system. The study offers a new design strategy for highly efficient piezocatalysts in the PF systems, enabling a cost‐effective and sustainable water treatment approach.

Customized Heteronuclear Dual Single-Atom and Cluster Assemblies via D-band Orchestration for Oxygen Reduction Reaction.

The advanced oxygen reduction reaction (ORR) catalysts, integrating with well-dispersed single atom (SA) and atomic cluster (AC) sites, showcase potential in bolstering catalytic activity. However, the precise structural modulation and in-depth investigation of their catalytic mechanisms pose ongoing challenges. Herein, a proactive cluster lockdown strategy is introduced, relying on the confinement of trinuclear clusters with metal atom exchange in the covalent organic polymers, enabling the targeted synthesis of a series of multicomponent ensembles featuring FeCo (Fe or Co) dual-single-atom (DSA) and atomic cluster (AC) configurations (FeCo-DSA/AC) via thermal pyrolysis. The designed FeCo-DSA/AC surpasses Fe- and Co-derived counterparts by 18 mV and 49 mV in ORR half-wave potential, whilst exhibiting exemplary performance in Zn-air batteries. Comprehensive analysis and theoretical simulation elucidate the enhanced activity stems from adeptly orchestrating dz2-dxz and O 2p orbital hybridization proximate to the Fermi level, fine-tuning the antibonding states to expedite OH* desorption and OOH* formation, thereby augmenting catalytic activity. This work elucidates the synergistic potentiation of active sites in hybrid electrocatalysts, pioneering innovative targeted design strategies for single-atom-cluster electrocatalysts.

Optimization of BIPV Utilization with Parametric Approach: Case Study on Nearly Zero Carbon Building Studio Design in Medan, Indonesia

Buildings significantly consume fossil energy, leading to substantial carbon emissions contributing to global warming and rising sea levels. These environmental impacts pose serious challenges, necessitating a shift towards sustainable building designs. By integrating clean energy solutions into building architecture, we can reduce the environmental burden of emissions. This approach mitigates adverse effects on living organisms and ecosystems and promotes long-term sustainability and resilience in urban development. Building-Integrated Photovoltaic (BIPV) systems represent one such approach for substituting fossil energy. However, implementing BIPV effectively necessitates comprehensive analysis considering numerous parameters and variables. This paper introduces building design strategies employing the BIPV approach. The decision-making process in designing alternatives utilizes parametric methods, recognized for their ability to yield optimization results for various variables through the development of design algorithms. The study focuses on the design of a studio building at the University of North Sumatra. Comparative analysis of the results obtained through parametric design aims to identify the most favorable design outcomes. The research includes developing a parameterized design algorithm, workflow, and assessment results for selecting optimal design alternatives. The results indicate that the placement of PV panels on the side area (PVOS) has more potential than placement on the top area (PVOT). Despite the PVOT area being observed to be 0.57% smaller than PVOS, PVOS shows a significant increase in total Incident Radiation (IR), average IR, and total Energy Generated by 137.14%, 128.40%, and 132.97%, respectively.

Polarization regulation in core-shell HNTs@Metal/C for high-performance of electromagnetic wave absorption

Enhancing polarization loss is an effective method to improve electromagnetic wave absorption (EMA) performance. However, constructing more interfaces and inducing defects is a significant challenge in polarization regulation. This paper reports synthesizing a core-shell structure HNTs@M/C (M=Cu, Co, Zn) by pyrolysis of metal-organic frameworks (MOFs). The enhancement of conduction loss is attributed to the electronic conduction network formed by the carbon layer and the metal particles. Co nanoparticles (NPs) create more interfaces with the carbon layer, significantly boosting polarization performance. Additionally, Zn sublimation induces numerous defects in the carbon layer, leading to cumulative amplification of polarization and stronger dielectric resonances in HNTs@Zn/C. With a thickness of 2.4 mm, the HNTs@Zn/C achieve an effective absorption bandwidth (EAB) of 6.9 GHz, covering the entire Ku-band with a minimum reflection loss of −61 dB. This work provides design strategies for interfacial and point interaction of polarization regulation.

High-Throughput screening of TM1TM2/N6–1 (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Mo) as effective electrocatalysts for nitrogen fixation

The electrochemical nitrogen reduction reaction (NRR) is an emerging nitrogen fixation method in recent years. Double-atom catalysts compensate for the disadvantage of single-atom catalysts having only one active site, improving catalytic reaction activity. Herein, using a four-step high-throughput screening strategy with density functional theory (DFT) calculations, 45 homonuclear and heteronuclear catalysts, namely, transition metal dimers anchored on nitrogen-doped graphene (TM1TM2/N6–1, TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Mo), were systematically studied to evaluate their catalytic performance for NRR. Our results showed that 16 catalysts stand out, among them, ScMo/N6–1 has an ultralow limiting potential of -0.09 V and a Faradaic efficiency of 100 %. This work provides a group of promising candidates and a reasonable high-throughput design strategy for NRR catalysts.

Dual-polarized transmissive metasurfaces for near-unitary-NA analog spatial computing empowered by impedance matching and mismatching.

In recent years, due to the increasing requirement for real-time and massive data processing, optical analog computation has arisen as a promising alternative to digital computation. Optical spatial differentiation plays a fundamentally important role in various emerging technologies, including augmented reality, autonomous driving, and object recognition. However, previous demonstrations encountered several limitations, such as the dependence on polarization states and a typically limited numerical aperture (NA) of about 0.5, especially in the transmission mode. Here, a new, to our knowledge, design strategy based on the evolution between impedance matching and mismatching in a metasurface is proposed to fill this gap, which can perform dual-polarized second-order derivative for image processing. Our scheme enables high transmission under dual polarization over an 85° incident angle range (NA = 0.996), resulting in more than twofold spatial resolution. Our work paves the way for polarization-insensitive high-resolution signal and image processing in the terahertz region.

Peptide-Based Drugs: Development and Therapeutic Applications

Current advances in knowledge about peptides as drugs are of great significance; They have planning potentialities in different sections of medicinal practice. This review will summarize the progress in the synthesis and the biological activities of the peptide-based drug, along with some of the uses. We start with the historical aspect and key points in the development of the corresponding field. In general, the development part describes the approaches of peptides synthesis, design strategies, screening methods, and optimization for stability and bioavailability. We then describe the action of such mechanisms as with respect to receptors, enzymes, and peptides that can penetrate cells. It has also expanded the assessment of the description of peptide drugs in the treatment of cancer, cardiovascular diseases, metabolic diseases, neurological diseases, infectious diseases, and immunotherapy. We cover both the problems in the formation of peptide drugs like stability, delivery, and regulatory issues and the opportunities like nanotechnology, bioprinting, and CRISPR. Last, we discuss the outlook of the peptide-based therapeutics and review features, which are promising for the development of new trends and perspectives of application. The present review is intended to give an up-to-date and easy to grasp information regarding the status and perspectives of peptide-associated medicines in contemporary pharmacology.

Structural design of "fitness" and "feasibility" of body-fitted stent and its mechanical analysis

To address the conflict between the "fitness" and "feasibility" of body-fitted stents, this paper investigates the impact of various smoothing design strategies on the mechanical behaviour and apposition performance of stent. Based on the three-dimensional projection method, the projection region was fitted with the least squares method (fitting orders 1-6 corresponded to models 1-6, respectively) to achieve the effect of smoothing the body-fitted stent. The simulation included the crimping and expansion process of six groups of stents in stenotic vessels with different degrees of plaque calcification. Various metrics were analyzed, including bending stiffness, stent ruggedness, area residual stenosis rate, contact area fraction, and contact volume fraction. The study findings showed that the bending stiffness, stent ruggedness, area residual stenosis rate, contact area fraction and contact volume fraction increased with the fitting order's increase. Model 1 had the smallest contact area fraction and contact volume fraction, 77.63% and 83.49% respectively, in the incompletely calcified plaque environment. In the completely calcified plaque environment, these values were 72.86% and 82.21%, respectively. Additionally, it had the worst "fitness". Models 5 and 6 had similar values for stent ruggedness, with 32.15% and 32.38%, respectively, which indicated the worst "feasibility" for fabrication and implantation. Models 2, 3, and 4 had similar area residual stenosis rates in both plaque environments. In conclusion, it is more reasonable to obtain the body-fitted stent by using 2nd to 4th order fitting with the least squares method to the projected region. Among them, the body-fitted stent obtained by the 2nd order fitting performs better in the completely calcified environment.

Semi-rational engineering of ω-transaminase for enhanced enzymatic activity to 2-ketobutyrate

Transaminases (EC 2.6.1.X, TAs) are important biocatalysts in the synthesis of chiral amines, and have significant value in the field of medicine. However, TAs suffer from low enzyme activity and poor catalytic efficiency in the synthesis of chiral amines or non-natural amino acids, which hinders their industrial applications. In this study, a novel TA derived from Paracoccus pantotrophus (ppTA) that was investigated in our previous study was employed with a semi-rational design strategy to improve its enzyme activity to 2-ketobutyrate. By using homology modeling and molecular docking, four surrounding sites in the substrate-binding S pocket were selected as potential mutational sites. Through alanine scanning and saturation mutagenesis, the optimal mutant V153A with significantly improved enzyme activity was finally obtained, which was 578 % higher than that of the wild-type ppTA (WT). Furthermore, the mutant enzyme ppTA-V153A also exhibited slightly improved temperature and pH stability compared to WT. Subsequently, the mutant was used to convert 2-ketobutyrate for the preparation of L-2-aminobutyric acid (L-ABA). The mutant can tolerate 300 mM 2-ketobutyrate with a conversion rate of 74 %, which lays a solid foundation for the preparation of chiral amines.

Dual-Porous ZIF-8 Heterogeneous Catalysts with Increased Reaction Sites for Efficient PET Glycolysis

Poly(ethylene terephthalate) (PET) has been widely used for drink bottles, food packing, films, and fibers, resulting in millions of tons of waste PET. Less than 10% of that waste is recycled, and the rest is discarded or incinerated. Waste PET upcycling employs chemical recycling and particularly glycolysis to create the bis(2-hydroxyethyl) terephthalate (BHET) monomer. Herein, we report a dual-porous zeolitic imidazolate framework-8 nanoparticle (DPZIF-8) heterogeneous catalyst for efficient PET glycolysis. The DPZIF-8 nanoparticles were prepared using a triethylamine modulator, which can control the nucleation and growth mechanisms of the ZIF-8 nanoparticles. The DPZIF-8 nanoparticles include both intrinsic micropores and particle-particle adhesion-induced mesopores that can provide a larger external surface area of the zinc sites in the ZIF-8 architecture. The PET glycolysis catalyzed by DPZIF-8 at 180 °C and 1 atm for 4 h shows a PET conversion of 91.7% and a BHET yield of 76.1%, the latter particularly being much higher than with a traditional heterogeneous ZIF-8 catalyst. This dual-porous structure rational design strategy can be versatile for other metal–organic frameworks (MOFs) to increase the interfacial catalytic reaction sites between the metal–organic framework and the polymer, enhancing the PET depolymerization performance and efficiency.

Analysis of cyclone separator solutions depending on spray ejector condenser conditions

The core design strategy for minimizing CO2 emissions in gas power plant entails combining a spray ejector condenser (SEC) and separator to accomplish steam condensation and CO2 purification. This innovative process involves direct-contact condensation of steam with CO2, facilitated by interaction with a subcooled water spray, along with a cyclone separator mechanism intended for generating pure CO2. The investigation of the SEC section, both experimentally and analytically, provides crucial insights into its operational dynamics. Given the susceptibility of cyclone efficiency to fluctuations in SEC conditions, this research endeavors to examine the impacts of CO2 volumetric flow rate and droplet break-up within the SEC on the separation efficacy of the cyclone separator. Additionally, the impact of cone size on the performance of the cyclone has been investigated. Here, a three-dimensional, transient, and turbulent cyclone separator is numerically simulated using Ansys Fluent 2021 R1. The Reynolds Stress Model is employed to simulate turbulent flow, while a mixture model is utilized to replicate swirl two-phase flow within the separators. The findings revealed that reductions in steam and CO2 flow rates were associated with a decrease in outlet temperature but an increase in SEC inlet temperature, leading to a rise in temperature difference and heat transfer rate. Furthermore, an augmentation in cyclone cone size (from 0.2 to 0.5 m) resulted in enhanced separation efficiency (from 77.30 % to 80.98 %) alongside an elevation in pressure drop (from 6.08 Pa to 10.91 Pa), suggesting a compromise between CO2 purification and energy consumption. Additionally, elevated CO2 flow rates induced a rise in pressure drop and separation efficiency, ultimately achieving maximum efficiency at a rate of 24 gs. Moreover, the exploration into droplet breakup manifesting in a boost in separation efficiency from 50.98 % to 100 % across droplet diameters ranging from 1 to 20 μm.

Nickel sulfide nanoparticles decorated on carbon spheres derived from Verbena officinalis for high-performance asymmetric all-solid-state flexible supercapacitors

The crafting and development of electrode materials possessing extensive energy storage capacities, alongside their adherence to environmental and economic principles, along with their outstanding capacitive behaviors, stand as pivotal elements in propelling the technological progress of supercapacitors. In this study, we utilized discarded Verbena officinalis (VOCs) as a carbon substrate and successfully synthesized porous hollow carbon spheres through an in-situ hydrothermal method, subsequently depositing NiS nanoparticles to form a shell-like structured material. The optimized VOCs/NiS-3 composite material exhibited an exceptional specific capacitance of 202.8 mAh g−1 at a current density of 1.0 A g−1; it maintained 71 % of its capacitance even at a high current density of 10 A g−1 (144.2 mAh g−1). After enduring 10,000 charge-discharge iterations, the preservation of charge storage capacity was 81.7 %, highlighting the material's outstanding performance in terms of rapid charge-discharge rates and enduring stability. Furthermore, within a PVA/KOH gel electrolyte, we fabricated an asymmetric all-solid-state supercapacitor device that delivered an energy density of 32.58 Wh k g−1 at a power density of 800 W k g−1. The device sustained a capacitance loss rate of 9.9 % and a coulombic efficiency of 96.8 % after 5000 cycles. Even after 3000 repeated bending at 120°, the capacitance retention reached 88.3 %, indicating the device's exceptional specific capacitance, flexibility and longevity. This research offers a renewable and waste-resource recycling design strategy for synthesizing outstanding-performance, flexible, all-solid-state supercapacitor electrode materials with NiS deposited on discarded biomass carbon, unveiling considerable potential for enhancing energy storage efficiency.

Design of functionally graded porous lattice structure tibial implant for TAR

Use of porous lattice structures and functionally graded (FG) implants in orthopaedic applications has emerged as a promising solution to reduce stress shielding. However, there is a notable research gap in examining the effects of post-operative scenarios within the lattice pores and different porosity distribution laws in functionally graded porous lattice structure (FGPLS) implants on the biomechanical performance of tibial implant for total ankle replacement (TAR). The objective of the study is to investigates the effects of both post-operative tissues and various porosity distribution laws on the biomechanical performance of tibial implant for TAR and proposes a new design strategy. CAD models for lattice structures at various porosities were developed to incorporate the effects of post-operative tissues such as fibrous tissue, cartilage, immature bone, and mature bone. The pore spaces of these lattice structures were assumed to be filled with the post-operative ingrowth tissues. The lattice structure and these tissues together form the Representative volume element (RVE), whose effective properties were calculated using Asymptotic homogenization (AH) technique. Equations linking mechanical properties and porosity were established and used to assign mechanical properties to macro-FE models of FGPLS tibial implants based on three different power laws i.e. n = 0.1,1 and 5. Macro-FE models for intact and implanted tibia bones were developed using homogeneous properties of cortical bone and heterogeneous cancellous bone properties. The proximal part of the tibia was fixed, and a compressive load was applied through the anterior nodes of the meniscal bearing to represent dorsiflexion loading during normal walking. The Finite Element Analysis (FEA) was utilized to investigate the biomechanical performance of these implanted models in terms of stress distribution in the tibia bone and implant-bone micromotion. A comparison was made between models with solid metallic implants and those with FGPLS implants. Additionally, models with varying post-operative tissues in the pore space were compared, as well as models with different porosity variation laws were also compared. Results demonstrated that models implanted with FGPLS implants having porosity variation based on power law n = 0.1 showed increased bone stress and micromotion compared to those with solid metallic implants. Specifically, in models with FGPLS implants with porosity variation based on a power law of n = 0.1, the bone area with stress ranging from 2–5 MPa increased significantly in the periprosthetic region compared to models with solid metallic implants. The bone stress value for the majority of the region above the medial and lateral peg increased from 1–2 MPa to 2–5 MPa. Although there was a slight increase in micromotion values, they remained below the acceptable threshold of 50 µm. Models with porosity variations based on power laws n = 1 and n = 5 exhibited similar bone stress and micromotion results as solid metallic implants. Additionally, no significant difference in bone stresses was observed for different stages of bone ingrowth at pore space. These findings indicate that both the porous structure and porosity distribution within the implant significantly influence the biomechanical performance of tibial implants for TAR. So, it can be concluded that FGPLS implants with power law n = 0.1 are effective in reducing stress shielding and supporting the long-term survival of TAR by increasing bone stress and reducing the chances of aseptic loosening due to implant induced adaptive bone remodelling.

Fracture mechanics of bi-material lattice metamaterials

The advent of additive manufacturing technology empowers precise control of multi-material components or specific defects in lightweight lattice metamaterials, however, fracture mechanics and toughening design strategies in such metamaterials remain enigmatic. By incorporating theoretical analysis, numerical simulation, and experimental investigation, our study reveals that stretch-bend synergistic strut deformations caused by bi-material components or topology defects contribute notably tougher lattice structures surpassing its ideal single-material lattices. A peak fracture energy at a critical modulus ratio was found in a designed bi-material lattice composed of triangular soft struts and hexagonal stiff struts, which originates from the shift of fracture modes at crack tip from strut bending to stretching dominated failure modes as the modulus of soft struts increases, where the compromise in competition between bending-enhanced and stretching-weakened energy dissipations of struts deformations results in the maximized fracture energy. A parametric design protocol was proposed to optimize fracture energy of bi-material lattices through tuning the modulus ratio and relative density. Furthermore, the concept of stretch-bend synergistic toughening can also be applied to make tougher single-material lattices with specific topological defects. Our findings not only provide physical insights into directing crack propagation but also provide quantitative guidance to optimize fracture resistance within low-density tough lattice metamaterials.

A new strategy for the preparation of polylactic acid composites with UV resistance, light conversion, and antibacterial properties

A novel rare earth complex, Eu(IAA)2(phen)2 (EuIP), was synthesized by solution-based synthesis method. Then, EuIP and polylactic acid (PLA) were melt-blended at 190 °C to obtain a multifunctional PLA/EuIP composite. The incorporation of EuIP provided PLA/EuIP composites with good light conversion ability. Under UV irradiation, PLA/EuIP composites converted the absorbed UV light into red light. Moreover, the PLA/1.0EuIP composite exhibited excellent light transmittance of 88 % in the visible region and showed strong red emission under UV light. After UV irradiation for 96 h, the molecular weights and mechanical properties of neat PLA decreased dramatically. Interestingly, the molecular weights and mechanical properties of PLA/EuIP composites did not deteriorate after 96 h of UV irradiation. The reason was that EuIP could absorb UV light and utilize the absorbed energy to emit red fluorescence. Furthermore, PLA/EuIP composites showed good antibacterial activities against E. coli and S. aureus. In addition, in vitro cell experiments showed that PLA/EuIP composites was suitable for the growth of murine breast cancer (4 T1) cells. Besides, enzymatic degradation testing also proved that PLA/EuIP composites had good biodegradability. This work provides an ingenious design strategy for the preparation of PLA/EuIP composites possessing light conversion ability, UV resistance, and antibacterial properties.

Construction of HaloTag-based macromolecular probe for multiple logic gates and photoactivatable bioimaging

Protein bioconjugation has emerged as one of the most valuable tools for the development of protein-based biochemical assays. Herein, we report a fluorescent macromolecular probe RF12_POI, in which the coumarin derivative RF12 is specifically conjugated onto the HaloTag fused protein of interest (POI) to achieve a dual stimuli-mediated fluorescence response. RF12 is first obtained by installing a photo-cleavable 1-ethyl-2-nitrobenzyl group onto the C7 hydroxy moiety of coumarin fluorophore with a HaloTag ligand attaching to the acid-labile 1,3-dioxane moiety. Upon stimulation, RF12_Halo exhibits a sequential fluorescence response to photon/H+ on both liquid and solid interfaces. Through the conjugation of RF12 onto the GFP_Halo protein, RF12_GFP_Halo presents a fluorescence resonance energy transfer (FRET) from photo-cleaved RF12 to GFP in the protein complex. Furthermore, by utilizing the stimuli-responsive fluorescence characteristics of coumarin derivatives RF12 (photon/H+) and RF16 (H2O2/H+), we construct RF12/RF16_POI based protein films and achieve multiple applications of logic circuits, including AND, OR, XOR, INHIBIT, Half-adder or Half-subtractor. In these circuits, the output value of I/I0 is dependent on the input sequence of photon, H2O2, and H+. Additionally, we evaluate the fluorescence labeling ability of RF12 to intracellular IRE1_Halo protein and demonstrate that RF12 containing the HaloTag ligand could be precisely retained in cells to track IRE1_Halo protein. Hence, we provide a unique structural design strategy to construct fluorescence dual-responsive macromolecules for information encryption and cellular protein visualization.

Hierarchical nanolayered structures-enabled record-high fracture resistant zircaloy

As a widely used nuclear structural material, zirconium (Zr) alloys are susceptible to brittle hydride-induced cracking. The intrinsic inability to arrest this cracking tendency in Zr poses a significant threat to the service safety of Zr cladding tubes. Here, we propose a microstructural design strategy, by introducing a hierarchical nanolayered duplex-phase structure in the Zr-2.5Nb alloy, to effectively inhibit the propagation of cracks. An unprecedented fracture toughness of KJIc ∼ 165 MPa·m1/2, corresponding to JIc ∼ 256 kJ/m2, is achieved due to the uniform and dense plastic deformation that develops ahead of the crack tip, which is uncharacteristic of Zr-based materials. Our analysis reveals that the effective crack tip blunting occurs because the high density of multiply oriented α/β interfaces in the hierarchical Zr-2.5Nb alloy stimulates ample <c+a> dislocations and facilitates deformation twin nucleation, both of which are challenging to activate in conventional Zr-based materials at room temperature. The exceptional fracture toughness enabled by the hierarchical nanolayered structure provides a new pathway to designing damage-tolerant hexagonal metals for safety-critical applications.