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Eutectogels, consisting of three-dimensional polymeric networks saturated with deep eutectic solvents (DESs), present a promising option for soft ionic conductors. Instead of modifying polymer chains, we propose a new DES system comprising phytic acid (PA) and choline chloride (ChCl), which enhances dynamic and interactive bonding with polymeric networks to create innovative eutectogels. Here, we develop polyfunctional eutectogels (PETGs) by encapsulating polyvinyl alcohol (PVA) networks with our DES using an evaporation-induced confinement strategy. Experimental validation and numerical calculations demonstrate that PA forms high-density dynamic hydrogen bonds with PVA while shielding hydrogen bonds between PVA chains. This results in a multiple hydrogen-bond-shielded amorphous network (MHSN) with undetectable crystalline regions, thereby promoting ion migration to ensure high conductivity. Moreover, our PETG exhibits rapid self-healing, freeze resistance, self-adhesion, antibacterial properties, and dual sensitivities attributable to the MHSN. We demonstrate the potential of PETGs for applications in motion sensing, machine learning, human-machine interaction, and energy harvesting.

Visual affordance grounding aims to segment all possible interaction regions between people and objects from an image/video, which benefits many applications, such as robot grasping and action recognition. Prevailing methods predominantly depend on the appearance feature of the objects to segment each region of the image, which encounters the following two problems: 1) there are multiple possible regions in an object that people interact with and 2) there are multiple possible human interactions in the same object region. To address these problems, we propose a hand-aided affordance grounding network (HAG-Net) that leverages the aided clues provided by the position and action of the hand in demonstration videos to eliminate the multiple possibilities and better locate the interaction regions in the object. Specifically, HAG-Net adopts a dual-branch structure to process the demonstration video and object image data. For the video branch, we introduce hand-aided attention to enhance the region around the hand in each video frame and then use the long short-term memory (LSTM) network to aggregate the action features. For the object branch, we introduce a semantic enhancement module (SEM) to make the network focus on different parts of the object according to the action classes and utilize a distillation loss to align the output features of the object branch with that of the video branch and transfer the knowledge in the video branch to the object branch. Quantitative and qualitative evaluations on two challenging datasets show that our method has achieved state-of-the-art results for affordance grounding. The source code is available at: https://github.com/lhc1224/HAG-Net.

Unconventional 1T′-phase transition metal dichalcogenides (TMDs) have aroused tremendous research interest due to their unique phase-dependent physicochemical properties and applications. However, due to the metastable nature of 1T′-TMDs, the controlled synthesis of 1T′-TMD monolayers (MLs) with high phase purity and stability still remains a challenge. Here we report that 4H-Au nanowires (NWs), when used as templates, can induce the quasi-epitaxial growth of high-phase-purity and stable 1T′-TMD MLs, including WS2, WSe2, MoS2and MoSe2, via a facile and rapid wet-chemical method. The as-synthesized 4H-Au@1T′-TMD core–shell NWs can be used for ultrasensitive surface-enhanced Raman scattering (SERS) detection. For instance, the 4H-Au@1T′-WS2NWs have achieved attomole-level SERS detections of Rhodamine 6G and a variety of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins. This work provides insights into the preparation of high-phase-purity and stable 1T′-TMD MLs on metal substrates or templates, showing great potential in various promising applications.

The fabrication of hierarchical and porous structures holds significant promise in biomedical science, aerospace, and related fields. Despite advancements in 3D printing technology that have enhanced the capability of complex porous structures, its application in metal fabrication remains challenging. In this paper, we introduce a method involving a 3D printed sacrificial template, created by the material extrusion process, for magnesium (Mg) infiltration. This method facilitates the production of porous Mg scaffolds, with the templates subsequently being water-leached. The morphology, shrinkage rate, compressive strength, and types of lattices of templates were observed and assessed to determine their viability. Further, comprehensive compression tests and cell adhesion experiments were conducted on the Mg scaffolds to evaluate their performance. The results suggest that the templates must possess adequate strength and continuous flow channels for successful Mg infiltration. The scaffolds experienced an average of about 30 % shrinkage from the initial design to the final structure. The porous Mg scaffolds exhibit enhanced compressive strength (47.48 ± 0.84 MPa) at lower porosity (0.52) and demonstrate satisfactory biocompatibility. This research highlights the efficacy and low cost of the template replication method in generating mechanically superior porous Mg scaffolds with customized pore sizes and structures. In future research, this method also holds promise for applications involving newly developed alloys.

Recently, certain ferroelectric tunnel junctions (FTJs) exhibit non-volatile modulations on photoresponse as well as tunneling electroresistance (TER) effects related to ferroelectric polarization states. From the opposite perspective, the corresponding polarization states can be read by detecting the levels of the photocurrent. In this study, we fabricate a novel amorphous selenium (a-Se)/PbZr0.2Ti0.8O3(PZT)/Nb-doped SrTiO3(NSTO) heterojunction, which exhibits a high TER of 3 × 106. Unlike perovskite oxide FTJs with a limited ultraviolet response, the introduction of a narrow bandgap semiconductor (a-Se) enables self-powered photoresponse within the visible light range. The self-powered photoresponse characteristics can be significantly modulated by ferroelectric polarization. The photocurrent after writing polarization voltages of +4 and −5 V exhibits a 1200% increase. Furthermore, the photocurrent could be clearly distinguished after writing stepwise polarization voltages, and then a multistate information storage is designed with nondestructive readout capacity under light illumination. This work holds great significance in advancing the development of ferroelectric multistate photoelectronic memories with high storage density and expanding the design possibilities for FTJs.

Objective: To observe the efficacy of using electroacupuncture (EA) plus stuck-needle lifting method to treat intractable facial paralysis based on the myofascial theory. Methods: Ninety patients with intractable facial paralysis were divided into a control group and an observation group using the random number table method, with 45 cases in each group. The control group was given conventional EA treatment, and the observation group received EA plus the stuck-needle lifting method based on the myofascial theory for 4 consecutive weeks, 6 sessions each week. The electromyographic results, modified Portmann scale (MPS) score, facial nerve function index (FNFI), and total effective rate were compared. Results: There were no significant differences in the MPS and FNFI scores between the two groups before treatment (P>0.05). After treatment, the total effective rate and FNFI and MPS scores were notably higher in the observation group than in the control group (P<0.05). There were no significant differences in the electromyographic readings between the two groups before the intervention (P>0.05). After the intervention, the observation group had a shorter blink reflex R1 latency and a higher facial nerve compound muscle action potential compared with the control group, and the between-group differences were statistically significant (P<0.05). Conclusion: EA plus stuck-needle lifting method based on the myofascial theory can enhance treatment efficacy for intractable facial paralysis.

Grade discrepancy between the primary tumor and venous tumor thrombus in renal cell carcinoma (RCC) provides pivotal prognostic value in nonmetastatic clear-cell RCC and can improve patient counseling and guide decision-making on adjuvant therapy.

A novel doubly interpenetrated indium-organic framework of 1has been assembled by In3+ions and highly conjugated biquinoline carboxylate-based bitopic connectors (H2L). The isolated 1exhibits an anionic framework possessing channel-type apertures repleted with exposed quinoline N atoms and carboxyl O atoms. Owing to the unique architecture, 1displays a durable photoluminescence effect and fluorescence quenching sensing toward CrO42–, Cr2O72–, and Cu2+ions with reliable selectivity and anti-interference properties, fairly high detection sensitivity, and rather low detection limits. Ligand-to-ligand charge transition (LLCT) was identified as the essential cause of luminescence by modeling the ground state and excited states of 1using DFT and TD-DFT. In addition, the negatively charged framework has the ability to rapidly capture single cationic MB, BR14, or BY24 and their mixture, including the talent to trap MB from the (MB + MO) system with high selectivity. Moreover, intrinsic light absorption capacity and band structure feature endow 1with effective photocatalytic decomposition ability toward reactive dyes RR2 and RB13 under ultraviolet light. Notably, after further polishing the band structure state of 1by constructing the S-scheme heterojunction of In2S3/1, highly efficient photocatalytic detoxification of Cr(VI) and degradation of reactive dyes have been fully achieved under visible light. This finding may open a new avenue for designing novel multifunctional MOF-based platforms to address some intractable environmental issues, i.e., detection of heavy metal ions, physical capture of pony-sized dyes, and photochemical decontamination of ultrastubborn reactive dyes and highly toxic Cr(VI) ions from water.

Serum united urine metabolic analysis comprehensively reveals the disease status for kidney diseases in particular. Thus, the precise and convenient acquisition of metabolic molecular information from united biofluids is vitally important for clinical disease diagnosis and biomarker discovery. Laser desorption/ionization mass spectrometry (LDI-MS) presents various advantages in metabolic analysis; however, there remain challenges in ionization efficiency and MS signal reproducibility. Herein, we constructed a self-assembled hyperbranched black gold nanoarray (HyBrAuNA) assisted LDI-MS platform to profile serum united urine metabolic fingerprints (S-UMFs) for diagnosis of early stage renal cell carcinoma (RCC). The closely packed HyBrAuNA afforded strong electromagnetic field enhancement and high photothermal conversion efficacy, enabling effective ionization of low abundant metabolites for S-UMF collection. With a uniform nanoarray, the platform presented excellent reproducibility to ensure the accuracy of S-UMFs obtained in seconds. When it was combined with automated machine learning analysis of S-UMFs, early stage RCC patients were discriminated from the healthy controls with an area under the curve (AUC) > 0.99. Furthermore, we screened out a panel of 9 metabolites (4 from serum and 5 from urine) and related pathways toward early stage kidney tumor. In view of its high-throughput, fast analytical speed, and low sample consumption, our platform possesses potential in metabolic profiling of united biofluids for disease diagnosis and pathogenic mechanism exploration.

The clinical diagnosis of renal cell carcinoma (RCC) is constantly evolving. Diagnostic imaging of RCC relying on enhanced computed tomography (CT) and magnetic resonance imaging (MRI) is commonly used for renal mass characterization and assessment of tumour thrombosis, whereas pathology is the gold standard for establishing diagnosis. However, molecular imaging is rapidly improving the clinical management of RCC, particularly clear-cell RCC. Molecular imaging aids in the non-invasive visualization and characterization of specific biomarkers such as carbonic anhydrase IX and CD70 within the tumours, which help to assess tumour heterogeneity and status. Target-specific molecular imaging of RCCs will substantially improve the diagnostic landscape of RCC and will further facilitate clinical decision-making regarding initial staging and re-staging, monitoring of recurrence and metastasis, patient stratification and selection, and the prediction and evaluation of treatment responses.

Texture recognition is a challenging visual task since its multiple primitives or attributes can be perceived from the texture image under different spatial contexts. Existing approaches predominantly built upon CNN incorporate rich local descriptors with orderless aggregation to capture invariance to the spatial layout. However, these methods ignore the inherent structure relation organized by primitives and the semantic concept described by attributes, which are critical cues for texture representation. In this paper, we propose a novel Multiple Primitives and Attributes Perception network (MPAP) that extracts features by modeling the relation of bottom-up structure and top-down attribute in a multi-branch unified framework. A bottom-up process is first proposed to capture the inherent relation of various primitive structures by leveraging structure dependency and spatial order information. Then, a top-down process is introduced to model the latent relation of multiple attributes by transferring attribute-related features between adjacent branches. Moreover, an augmentation module is devised to bridge the gap between high-level attributes and low-level structure features. MPAP can learn representation through jointing bottom-up and top-down processes in a mutually reinforced manner. Experimental results on six challenging texture datasets demonstrate the superiority of MPAP over state-of-the-art methods in terms of accuracy, robustness, and efficiency.

•Anthropogenic CO2(CANT) storage was investigated in the western North Pacific.•CANTinventories in water column and in specific water masses were estimated.•Subtropical mode water dominates CANTdynamics in the Kuroshio Recirculation region.

Self-powered operation and multifunctionality have significantly oriented the development of photodetectors (PDs), which could be realized through nanoarchitecture construction and energy band structure design. Herein, a self-powered wavelength-dependent dual-polarity response PD based on (CdS@PEDOT:PSS@Au) sandwich-structured core–shell nanorod arrays (NRAs) is proposed. The synthesis approach of this three-layer heterostructure consists of a hydrothermal reaction, spin coating, and thermal evaporation. The n-CdS/p-PEDOT:PSS junction and the PEDOT:PSS/Au Schottky junction at the interfaces provide two photocurrent driving forces in opposite directions, and their contribution to the net photocurrent is controlled by the incident light wavelength due to the different light absorption ranges of the CdS core and the PEDOT:PSS shell. As a result, the polarity of the photocurrent switches from negative to positive as the wavelength increases. In addition, the response speed of negative photocurrents (∼10 ms) is faster than that of positive photocurrents (∼100 ms), which is consistent with the underlying mechanism of the dual-polarity response. Furthermore, color discrimination and imaging capabilities are demonstrated by deploying the PDs as sensing pixels and recognizing green and red patterns. The sandwich-structured core–shell NRA heterojunction system introduces a novel idea for dual-polarity response PDs.

Graphene aerogels have gained considerable attention due to their unique physical properties, but their poor mechanical properties and lack of functionality have hindered their advanced applications. In this study, we propose a blend-spinning-assisted freeze-casting (BSFC) strategy to incorporate particle-modified carbon fibers into graphene aerogels for mechanical strengthening and functional enhancement. This method offers a great deal of freedom in the creation of customizable multimaterial, multiscale structural graphene aerogels. For example, we fabricated silicon carbide particle modified carbon fiber reinforced graphene (SiC/CF-GA) aerogels. The resulting aerogels display excellent properties such as being ultralightweight and highly resilient and having fatigue compression resistance (1000 cycles at 50% strain). Meanwhile, enhanced resilience inspired the effective strain-sensing capabilities of SiC/CF-GA aerogels with a sensitivity of 13.8 kPa–1. The adjustable dielectric properties due to SiC particle incorporation endow the SiC/CF-GA aerogel with a broad-band (8.0 GHz) effective electromagnetic wave attenuation performance. Besides, different particles could be incorporated into graphene aerogels via the BSFC strategy, allowing for customizable designs. Moreover, multifunctionalities were demonstrated by the modified aerogels, including noise absorption, thermal insulation, fire resistance, and waterproofing, further diversifying their practicality. Hence, the BSFC strategy provides a customized solution for fabricating modified graphene aerogels for advanced functional applications.

Phase transition with band gap modulation of materials has gained intensive research attention due to its various applications, including memories, neuromorphic computing, and transistors. As a powerful strategy to tune the crystal phase of transition-metal dichalcogenides (TMDs), the phase transition of TMDs provides opportunities to prepare new phases of TMDs for exploring their phase-dependent property, function, and application. However, the previously reported phase transition of TMDs is mainly irreversible. Here, we report a reversible phase transition in the semimetallic 1T′-WS2driven by proton intercalation and deintercalation, resulting in a newly discovered semiconducting WS2with a novel unconventional phase, denoted as the 1T′dphase. Impressively, an on/off ratio of >106has been achieved during the phase transition of WS2from the semimetallic 1T′ phase to the semiconducting 1T′dphase. Our work not only provides a unique insight into the phase transition of TMDs via proton intercalation but also opens up possibilities to tune their physicochemical properties for various applications.

The fungal pathogen Setosphaeria turcicacauses northern corn leaf blight (NCLB), which leads to considerable crop losses. Setosphaeria turcicaelaborates a specialized infection structures called appressorium for maize infection. Previously, we demonstrated that the S. turcicatriggers an S-phase checkpoint and ATR (Ataxia Telangiectasia and Rad3 related)-dependent self-protective response to DNA genotoxic insults during maize infection. However, how the regulatory mechanism works was still largely unknown. Here, we report a genome wide transcriptional profile analysis during appressorium formation in the present of DNA replication stress. We performed RNA-Seq analysis to identify S. tuicicagenes responsive to DNA replication stress. In the current work, we found that appressorium-mediated maize infection by S. turcicais significantly blocked by S-phase checkpoint. A large serial of secondary metabolite and melanin biosynthesis genes were blocked in appressorium formation of S. turcicaduring the replication stress. The secondary metabolite biosynthesis genes including alcohol dehydrogenase GroES-like domain, multicopper oxidase, ABC-transporter families, cytochrome P450 and FAD-containing monooxygenase were related to plant pathogen infection. In addition, we demonstrated that autophagy in S. turcicais up-regulated by ATR as a defense response to stress. We identified StATG3, StATG4, StATG5, StATG7 and StATG16 genes for autophagy were induced by ATR-mediated S-phase checkpoint. We therefore propose that in response to genotoxic stress, S. turcicautilizes ATR-dependent pathway to turn off transcription of genes governing appressorium-mediated infection, and meanwhile inducing transcription of autophagy genes likely as a mechanism of self-protection, aside from the more conservative responses in eukaryotes.

Taking the world’s largest green tide caused by the macroalga Ulva proliferain the South Yellow Sea as a natural case, it is studied here if macroalgae can perform inorganic carbon sequestration in the ocean. Massive macroalgae released large amounts of organic carbon, most of which were transformed by microorganisms into dissolved inorganic carbon (DIC). Nearshore field investigations showed that, along with seawater deoxygenation and acidification, both DIC and total alkalinity (TAlk) increased significantly (both >50%) in the areas covered by dense U. proliferaat the late-bloom stage. Offshore mapping cruises revealed that DIC and TAlk were relatively higher at the late-bloom stage than at the before-bloom stage. Laboratory cultivation of U. proliferaat the late-bloom stage further manifested a significant enhancement effect on DIC and TAlk in seawater. Sulfate reduction and/or denitrification likely dominated the production of TAlk. Notably, half of the generated DIC and almost all the TAlk could persist in seawater under varying conditions, from hypoxia to normoxia and from air–water CO2disequilibrium to re-equilibrium. The enhancement of TAlk allowed more DIC to remain in the seawater rather than escape into the atmosphere, thus having the long-term legacy effect of increasing DIC pool in the ocean.

Helmholtz resonance, based on resonance through a pore-and-cavity structure, constitutes the primary sound absorption mechanism in majority of sound-absorbing metamaterials. Typically, enhancing sound absorption in such absorbers necessitates substantial geometrical redesign or the addition of dissipative materials, which is non-ideal considering the volume and mass constraints. Herein, we introduce a new approach – that is to simply reshape the cavity, without alterations to its overall mass and volume – to drastically enhance sound absorption. This is achieved by bringing the cavity walls close to the pores where additional thermoviscous dissipation along these boundaries can occur. Experimentally validated, with three sides of the cuboid cavity close to the pore and at a particular pore–cavity geometry, a 44% gain in maximum absorption is achieved compared to the original structure. Through numerical simulations, we fully elucidate structure–property relationships and their mechanisms, and propose analytical models for design and optimization. Ultimately, utilizing this concept, we demonstrate a heterogeneously porous broadband (1500 to 6000 Hz) absorber that exhibits an excellent average absorption coefficient of 0.74 at a very low thickness of 18 mm. Overall, we introduce a new and universal concept that could revolutionize the design principles of Helmholtz resonators, and demonstrate its potential for designing advanced sound-absorbing metamaterials.

Multifunctional materials are in high demand for practical engineering applications. Owing to the ubiquitous noise and impact energy hazards in many settings, traditional materials and conventionally designed metamaterials are incapable of preventing these types of hazard simultaneously. Herein, we report a new paradigm, viaa decoupled approach, in the design of acousto-mechanical multifunctional metamaterials. We leverage the morphology of a Helmholtz resonator, such that the sound-absorbing and mechanical components are designed independently. For sound absorption, we adopt a coherent coupling design for a favorable resonant response, while for the mechanical response, we adopt customized struts. We then demonstrate our concept via3D printing. Experimentally measured remarkable broadband absorption in the practical low-frequency range (<1.0 kHz) is achieved. Absorption mechanisms are attributed to viscous and thermal boundary dissipation. Compression tests also reveal that the metamaterials are highly deformation resilient with a recovery of up to 98%, owing to both the lattice structure design and the viscoelastic behavior of the base material. Through this decoupled design, we further demonstrate the potential of our metamaterials in customizable absorption, strength, pseudo-reusability, and impact resistance. The proposed design paradigm broadens the horizon for the design of multifunctional materials, offering an impetus to their exploration for practical applications.

On-chip electrocatalytic microdevices (OCEMs) are an emerging electrochemical platform specialized for investigating nanocatalysts at the microscopic level. The OCEM platform allows high-precision electrochemical measurements at the individual nanomaterial level and, more importantly, offers unique perspectives inaccessible with conventional electrochemical methods. This protocol describes the critical concepts, experimental standardization, operational principles and data analysis of OCEMs. Specifically, standard protocols for the measurement of the electrocatalytic hydrogen evolution reaction of individual 2D nanosheets are introduced with data validation, interpretation and benchmarking. A series of factors (e.g., the exposed area of material, the choice of passivation layer and current leakage) that could have effects on the accuracy and reliability of measurement are discussed. In addition, as an example of the high adaptability of OCEMs, the protocol for in situ electrical transport measurement is detailed. We believe that this protocol will promote the general adoption of the OCEM platform and inspire further development in the near future. This protocol requires essential knowledge in chemical synthesis, device fabrication and electrochemistry.

Many American cities are testing autonomous shuttles (AS), or self-driving minibuses, as a new mode of public transportation. Existing AS studies often rely on stated preference (SP) surveys that require participants to imagine AS scenarios, or they evaluate short-term pilot programs, thus lacking long-term user insights – particularly in car-dependent suburban contexts. To address these limitations, we conducted a revealed preference (RP) study to identify critical factors influencing AS acceptance among users of Move Nona, the longest-running AS network in the United States, located in Lake Nona, a residential suburb in Orlando, Florida. This study expanded the Technology Acceptance Model (TAM) to include six latent factors: perceived ease of use, perceived usefulness, trust in AS safety, perceived AS reliability under inclement weather conditions, personal innovativeness, and environmental awareness. Our findings indicate that perceived usefulness, ease of use, and environmental awareness positively affect AS acceptance. Contrary to previous research, however, trust and personal innovativeness have minimal impact, suggesting that as users become more familiar with AS, they prioritize essential mobility aspects, such as travel speed and convenience, over technological novelty. These insights are valuable for decision-makers planning to adopt AS to enhance local transit services, while also contributing to the broader field of behavior analysis by corroborating an extended application of TAM in examining AS user acceptance.

The development of high-energy-density Li-ion batteries is hindered by the irreversible capacity loss during the initial charge-discharge process. Therefore, pre-lithiation technology has emerged in the past few decades as a powerful method to supplement the undesired lithium loss, thereby maximizing the energy utilization of LIBs and extending their cycle life. Lithium oxalate (Li2C2O4), with a high lithium content and excellent air stability, has been considered one of the most promising materials for lithium compensation. However, the sluggish electrochemical decomposition kinetics of the material severely hinders its further commercial application. Here, we introduce a recrystallization strategy combined with atomic Ni catalysts to modulate the mass transport and decomposition reaction kinetics. The decomposition potential of Li2C2O4is significantly decreased from ∼4.90V to ∼4.30V with a high compatibility with the current battery systems. In compared to the bare NCM//Li cell, the Ni/N-rGO and Li2C2O4composite (Ni-LCO) modified cell releases an extra capacity of ∼11.7 ​%. Moreover, this ratio can be magnified in the NCM//SiOxfull cell, resulting in a 30.4 ​% higher reversible capacity. Overall, this work brings the catalytic paradigm into the pre-lithiation technology, which opens another window for the development of high-energy-density battery systems.

This perspective highlights the representative progress of phase engineering of nanomaterials (PEN) with an emphasis on noble metals and transition metal dichalcogenides, and proposes future directions in this emerging field.

The growth of wafer-scale two-dimensional (2D) single crystals, especially transition metal dichalcogenides (TMDs), is significantly essential for various electronic applications. However, the growth of wafer-scale single-crystal TMD (sc-TMD) monolayers on commercial substrates still remains challenging. Recently, two works published in Nature Nanotechnologyhave independently reported a substrate-cutting strategy for epitaxial growth of wafer-scale sc-TMD monolayers, which might open up a new route for preparing wafer-scale sc-TMD monolayers on commercially scalable insulating substrates for future electronics.

Hierarchical porous materials are ubiquitous in nature and have inspired the fabrication of cellular structures for a multitude of applications. As an extrusion-based 3D printing technique, direct ink writing (DIW) allows for customizable design and accurate control of printed structures. Recently, its combination with colloidal processing methods used for bulk porous ceramics, such as emulsion templating, has further extended its capability of fabricating porous ceramics across multiple length scales. In light of the recent development, the ink formulation for emulsion-based DIW can be further explored, and there is still a need for a better understanding of the structure–property relationship. Herein, we introduce two types of gelling additives, i.e., poly(ethylenimine) (PEI) and Pluronic F-127, respectively, into particle-stabilized emulsions and fabricate hierarchical porous alumina lattices by DIW. We discover that the two gelling additives can lead to distinctive microstructures due to their different gelling mechanisms. Moreover, the 3D printed hierarchical porous ceramic lattices are found to exhibit a potential energy absorption property. The effects of ink formulations, including gelling additives and solid loading, on ink rheology, microstructure, and mechanical properties are investigated. The 3D printed hierarchical porous ceramic lattices exhibit a high average porosity of 73.7%–79.3% with an average compressive strength of 1.53–9.61 MPa and a specific energy absorption of 0.33–2.67 J/g. Featuring two distinctive microstructures with tunable structural features and mechanical properties, the 3D printed hierarchical porous ceramics in this study have potential in many applications, including lightweight structures, tissue engineering scaffolds, filtration, etc.

Given the destructive nature of hurricanes in tropical regions, pre-disaster evacuation has emerged as a critical approach for hurricane preparedness. Nevertheless, the compounding effects of natural hazards and the outbreak of infectious diseases, such as Covid-19, significantly challenge hurricane evacuation management. To investigate emergency responses under compound hazards, this study develops an activity-based model to measure the evacuation behaviors of individuals, using Hurricane Irma as a case study. Four scenarios are designed, including a single hurricane hazard, Hurricane Irma compounded with a pandemic like Covid-19, Hurricane Irma compounded with flood damage to the transportation network, and a combination of all these hazards. The metropolis-hasting algorithm is utilized to generate a population with socioeconomic attributes, which is then allocated to census block groups covering Palm Beach, Broward, Miami-Dade, and Monroe Counties in Florida. Datasets from multiple sources are used to measure evacuation decisions, which are subsequently simulated using MATSim. The results highlight the potential impacts of compound hazards on transportation systems, including increased congestions in scenarios involving compounded hurricanes and floods, especially between 10 a.m. and 7p.m. Moreover, a higher proportion of socially vulnerable populations is observed in scenarios involving compounded hurricanes and pandemics, particularly in the Key West area. The developed model could be further applied to measure the indirect impacts of natural hazards on transportation systems.

A small-strain sensitive and highly compressible strain sensor is urgently required to handle external complex pressure environments in wearable applications and artificial intelligence. Therefore, the development of a reasonable sensor structure to achieve low detection limitation and wide linear detection range is significant and challenging. Herein, a muscle-inspired anisotropic conductive polydimethylsiloxane (PDMS)/carbon black (CB)/thermoplastic polyurethane (TPU) foam (PCTF) was prepared by directional freezing and ultrasonic-dipping method. The density and porosity of PCTF are 0.18 g cm−3and 85.5%, respectively. Benefiting from the unique oriented structure, PCTF possesses good strain sensing performances, including ultra-low detection limit (0.002% strain), wide linear detection range (up to 82% strain and pressure over 500 kPa, logistic function R2=0.997), short response time (70 ms) and excellent sensing stability. In addition, PCTF demonstrates excellent properties as triboelectric nanogenerator (TEN(G) (2.5 × 3 cm2), including high triboelectric output (open-circuit voltage VOC=56 V) and high sensitivity (2.0 mV Pa−1), endowing PCTF with the motion state and running posture detecting ability. Moreover, PCTF-based strain sensors consisting of a plantar array can be employed to detect abnormal gait, including supination and pronation, providing a feasible strategy for training and personalized rehabilitation of the athletes.

Flexible strain sensors have developed rapidly and shown enormous application prospects in human motion detection, intelligent robots, and other fields in recent years. However, developing satisfactory strain sensors that meet the requirements of high sensitivity, wide detection range and prominent durability remains a significant challenge. Herein, we developed a flexible and wearable multifunctional fiber-shaped carbon black (CB) and thermoplastic polyurethane (TPU) strain sensor (defined as CTSS) by combining wet spinning and ultrasound. The CTSS possesses characteristics of lightweight, wide sensing range (>390 %), high sensitivity (up to 1414), short response and recovery time (200 ms), ultralow detection limit (0.005 % strain) and good durability. These advantages endow the CTSS with good capability to monitor complicated human activities efficiently (e.g., joint bending, facial expression and breathing). CTSS can also clearly distinguish different bending states. It was then used to monitor the steering of a car in real-time, proving its tremendous potential as high performance flexible electronics device. CTSS is then encapsulated with Ecoflex (E-CTSS) as a single packaged fiber, exhibiting good triboelectric nanogenerator (TENG) performance, with a maximum output voltage beyond 12V for a single packaged fiber, and can maintain stable output. Indicating that E-CTSS has self powered sensing capability.

• Functionally graded metallic foam was produced from template replication method. • The sound absorption performances of the graded foam can be customized. • The intersection points for sound absorption curves with two pore sizes can be predicted easily. • Sound absorption performances are changed when thickness proportions of pore sizes are changed. • Sound absorption performances are changed when the foam contains more pore sizes. In this study, functionally graded foam made of Inconel 625 superalloy was successfully produced using the template replication method, with open-cell polyurethane foams as a precursor. The products have a similar pore morphology as the templates and adjacent layers were successfully sintered together by particle bonding. Sound absorption experiments on graded metallic foams reveal that the sound absorption at particular frequency ranges can be improved by various permutations of foam layers. For graded foam of two distinct pore sizes, a mathematical equation was proposed to predict the location of the intersection point of the sound absorption curves, thereby aiding in graded foam design. An increase in sound absorption coefficients by resonance-like effects can be introduced before the intersection points by placing the foam layer of smaller pore size nearer to the sound source. The sound absorption performances can be further customized when the thickness proportion of the pore sizes is changed and when the number of distinct pore sizes used is increased. The sound absorption performance at lower frequencies is generally boosted by resonance-like effects when the layer of foam with the largest pore size is placed furthest from the sound source. Given the same composition of foam with a fixed thickness proportion of pore sizes, one can introduce resonance-like effects to improve the sound absorption performance compared to other permutations while possibly satisfying weight requirements in practical applications. This study provides valuable insights and mathematical guidelines in the design and manufacturing of functionally graded metallic foam for specific applications. [ABSTRACT FROM AUTHOR]

A novel type of all-ceramic SiC aerogel was fabricated by freeze casting and carbothermal reduction reaction processes using graphene oxide (GO) doped SiC nanowires suspensions as starting materials. The effect of GO addition (0, 1, 2, and 4 mg/mL) on the porous morphologies, chemical composition, and the electromagnetic (EM) performance of the SiC aerogels were investigated. The optimum all-ceramic SiC aerogel exhibits effective whole X-band attenuation (>90%) at a fixed thickness of 3.3 mm from room temperature to 400 °C. It is ultralight with a density of 0.2 g/cm3and possesses a low thermal conductivity of about 0.05 W/mK. The material composition remains stable at temperatures up to 800 °C. The lightweight, high thermal stability, low thermal conductivity, and excellent X-band attenuation performance at a fixed thin thickness make the all-ceramic SiC aerogels potential EM attenuation materials for many applications in harsh environments.

Cost-effective, rapid, and accurate virus detection technologies play key roles in reducing viral transmission. Prompt and accurate virus detection enables timely treatment and effective quarantine of virus carrier, and therefore effectively reduces the possibility of large-scale spread. However, conventional virus detection techniques often suffer from slow response, high cost or sophisticated procedures. Recently, two-dimensional (2D) materials have been used as promising sensing platforms for the high-performance detection of a variety of chemical and biological substances. The unique properties of 2D materials, such as large specific area, active surface interaction with biomolecules and facile surface functionalization, provide advantages in developing novel virus detection technologies with fast response and high sensitivity. Furthermore, 2D materials possess versatile and tunable electronic, electrochemical and optical properties, making them ideal platforms to demonstrate conceptual sensing techniques and explore complex sensing mechanisms in next-generation biosensors. In this review, we first briefly summarize the virus detection techniques with an emphasis on the current efforts in fighting again COVID-19. Then, we introduce the preparation methods and properties of 2D materials utilized in biosensors, including graphene, transition metal dichalcogenides (TMDs) and other 2D materials. Furthermore, we discuss the working principles of various virus detection technologies based on emerging 2D materials, such as field-effect transistor-based virus detection, electrochemical virus detection, optical virus detection and other virus detection techniques. Then, we elaborate on the essential works in 2D material-based high-performance virus detection. Finally, our perspective on the challenges and future research direction in this field is discussed.