Soft,body conformable electronics for thermoregulation enabled by kirigami

The application of thermoelectric devices(TEDs)for personalized thermoregulation is attractive for saving energy while balancing the quality of life.TEDs that directly attach to human skin remarkably minimized the energy wasted for cooling the entire environment.However,facing the extreme dynamic geometry change and strain of human skin,conventional TEDs cannot align with the contour of our bodies for the best thermoregulation effect.Hence,we designed a kirigami-based wearable TED with excellent water vapor permeability,flexibility,and conformability.Numerical analysis and experimental results reveal that our product can withstand various types of large mechanical deformation without circuit rupture.The stated outcome and proposed facile approach not only reinforce the development of wearable TEDs but also offer an innovative opportunity for different electronics that require high conformability.

Timing of carbonatite-hosted U-polymetallic mineralization in the supergiant Huayangchuan deposit,Qinling Orogen:Constraints from titanite U-Pb and molybdenite Re-Os dating

The newly-discovered supergiant Huayangchuan uranium(U)-polymetallic(Sr,Se,REEs,Ba,Nb and Pb)deposit is located in the Qinling Orogen,central China.The deposit underwent multistage mineralization,with the main carbonatite ore stage being the most important for the U,Nb,REE,Sr and Ba endowments.According to the mineral assemblages,the main carbonatite ore stage can be divided into three substages,i.e.,sulfate(Ba-Sr),alkali-rich U and REE-U mineralization.Main-stage titanite from the Huayangchuan igneous carbonatite are rich in high field strength elements(HFSEs,e.g.,Zr,Nb and REEs),and show clear elemental substitutions(e.g.,Ti vs.Nb+Fe+Al and Ca+Ti vs.Fe+Al+REE).High-precision LA-ICP-MS titanite dating yielded a U-Pb age of 209.0±2.9 Ma,which represents the mainstage mineralization age at Huayangchuan,and is coeval with the local carbonatite dyke intrusion.This mineralization age is further constrained by the Re-Os dating of molybdenite from the Huayangchuan carbonatite,which yielded a weighted mean age of 196.8±2.4 Ma.Molybdenite Re contents(337.55-392.75 ppm)and C-OSr-Nd-Pb isotopic evidence of the Huayangchuan carbonatite both suggest a mantle origin for the carbonatite.Our study supports that the Late Triassic carbonatite magmatism was responsible for the world-class U-Mo-REE mineralization in the Qinling Orogen,and that the regional magmatism and ore formation was likely caused by the closure of the Mianlue ocean and the subsequent North China-South China continent-continent collision.

Coupled trace element and SIMS sulfur isotope geochemistry of sedimentary pyrite:Implications on pyrite growth of Caixiashan Pb-Zn deposit

Colloform pyrite with core-rim texture is commonly deposited in carbonate platforms associated with the sulfide ores such as the Caixiashan Pb-Zn deposit.However,the genesis of colloform pyrite in Pb-Zn deposits,its growth controls and their geological implication are insufficiently understood.Integration of in-situ trace element and SIMS sulfur isotopes has revealed geochemical variations among these pyrite layers.These colloform pyrite occur as residual phases of core-rim aggregates,the cores are made up of very fine-grained anhedral pyrite particles,with some rims being made up of fine-grained and poorlycrystallized pyrite,while the other rims were featured with euhedral cubic pyrite.which are cemented by fine-grained calcite and/or dolomite with minor quartz.Sulfur isotope analysis shows that some wellpreserved rims have negative δ^34 S values(-28.12‰to-0.49‰),whereas most of the cores and rims have positive δ^34 S values(>0 to+44.28‰;peak at+14.91‰).Integrating with the methane and sulfate were observed in previous fluid inclusion study,we suggest that the 34 S depleted rims were initially formed by bacteria sulfate reduction(BSR),whereas the positive δ^34 S values were resulted from the sulfate reduction driven by anaerobic methane oxidation(AOM).The well-developed authigenic pyrite and calcite may also support the reaction of AOM.Combined with petrographic observations,trace element composition of the colloform pyrite reveals the incorporation and precipitation behavior of those high abundance elements in the pyrite:Pb and Zn were present as mineral inclusion and likely precipitated before Fe,as supported by the time-resolved Pb-Zn signal spikes in most of the analyzed pyrite grains.Other metals,such as Hg,Co and Ni,may have migrated as chloride complexes and entered the pyrite lattice.Arsenic and Sb,generally influenced by complex-forming reactions rather than substitution ones,could also enter the pyrite lattice,or slightly predate the precipitation of colloform pyrite as mineral inclusions,which are controlled by their hydrolysis constant in the ore fluids.The colloform pyrite may have grown inward from the rims.The successive BSR reaction process would enrich H^32/2S in the overlying water column but reduce the metal content,the nucleation of these pyrite rims was featured by strongly negative sulfur isotopes.The following AOM process should be activated by deformation like the turbidity sediment of the mudstone as the sulfide deposition are associated with fault activities that caused the emission of methane migration upward and simultaneously replenishing the metal in the column.The higher AOM reaction rate and the higher metal supply(not only Fe.but with minor other metals such as Pb and Zn) caused by sediment movement enhanced the metal concentration within the pyrite lattice.

Fuzzy distances based FMAGDM compromise ratio method and application

An extended compromise ratio method（CRM） based on fuzzy distances is developed to solve fuzzy multi-attribute group decision making problems in which weights of attributes and ratings of alternatives on attributes are expressed with values of linguistic variables parameterized using triangular fuzzy numbers.A compromise solution is determined by introducing the ranking index based on the concept that the chosen alternative should be as close as possible to the positive ideal solution and as far away from the negative ideal solution as possible simultaneously.This proposed method is compared with other existing methods to show its feasibility and effectiveness and illustrated with an example of the military route selection problem as one of the possible applications.

FINITE EXTENSIONS OF GENERALIZED BESSEL SEQUENCES TO GENERALIZED FRAMES

The objective of this paper is to investigate the question of modifying a givengeneralized Bessel sequence to yield a generalized frame or a tight generalized frame by finiteextension. Some necessary and sufficient conditions for the finite extensions of generalizedBessel sequences to generalized frames or tight generalized frames are provided, and everyresult is illustrated by the corresponding example.

Pressure-dependent electronic,optical,and mechanical properties of antiperovskite X_(3)NP(X=Ca,Mg):A first-principles study

Hydrostatic pressure provides an efficient way to tune and optimize the properties of solid materials without chang-ing their composition.In this work,we investigate the electronic,optical,and mechanical properties of antiperovskite X_(3)NP(X^(2+)=Ca,Mg)upon compression by first-principles calculations.Our results reveal that the system is anisotropic,and the lat-tice constant a of X_(3)NP exhibits the fastest rate of decrease upon compression among the three directions,which is different from the typical Pnma phase of halide and chalcogenide perovskites.Meanwhile,Ca_(3)NP has higher compressibility than Mg_(3)NP due to its small bulk modulus.The electronic and optical properties of Mg_(3)NP show small fluctuations upon compression,but those of Ca_(3)NP are more sensitive to pressure due to its higher compressibility and lower unoccupied 3d orbital energy.For example,the band gap,lattice dielectric constant,and exciton binding energy of Ca_(3)NP decrease rapidly as the pressure increases.In addition,the increase in pressure significantly improves the optical absorption and theoretical conversion effi-ciency of Ca_(3)NP.Finally,the mechanical properties of X_(3)NP are also increased upon compression due to the reduction in bond length,while inducing a brittle-to-ductile transition.Our research provides theoretical guidance and insights for future experi-mental tuning of the physical properties of antiperovskite semiconductors by pressure.

Beyond Antibiotics:Photo/Sonodynamic Approaches for Bacterial Theranostics

Rapid evolution and propagation of multidrug resistance among bacterial pathogens are outpacing the development of new antibiotics,but antimicrobial photodynamic therapy(aPDT)provides an excellent alternative.This treatment depends on the interaction between light and photoactivated sensitizer to generate reactive oxygen species(ROS),which are highly cytotoxic to induce apoptosis in virtually all microorganisms without resistance concern.When replacing light with low-frequency ultrasonic wave to activate sensitizer,a novel ultrasounddriven treatment emerges as antimicrobial sonodynamic therapy(aSDT).Recent advances in aPDT and aSDT reveal golden opportunities for the management of multidrug resistant bacterial infections,especially in the theranostic application where imaging diagnosis can be accomplished facilely with the inherent optical characteristics of sensitizers,and the generated ROS by aPDT/SDT cause broad-spectrum oxidative damage for sterilization.In this review,we systemically outline the mechanisms,targets,and current progress of aPDT/SDT for bacterial theranostic application.Furthermore,potential limitations and future perspectives are also highlighted.

Epidermal self-powered sweat sensors for glucose and lactate monitoring

Sweat could be a carrier of informative biomarkers for health status identification;therefore,wearable sweat sensors have attracted significant attention for research.An external power source is an important component of wearable sensors,however,the current power supplies,i.e.,batteries,limit further shrinking down the size of these devices and thus limit their application areas and scenarios.Herein,we report a stretchable self-powered biosensor with epidermal electronic format that enables the in situ detec-tion of lactate and glucose concentration in sweat.Enzymatic biofuel cells serve as self-powered sensing modules allowing the sweat sensor to exhibit a determination coefficient(R2)of 0.98 with a sensitivity of 2.48 mV/mM for lactate detection,and R2 of 0.96 with a sensitivity of 0.11 mV/μM for glucose detection.The microfluidic channels developed in an ultra-thin soft flexible polydimethylsiloxane layer not only enable the effective collection of sweat,but also provide excellent mechanical properties with stable performance output even under 30%stretching.The presented soft sweat sensors can be integrated at nearly any location of the body for the continuous monitoring of lactate and glucose changes during normal daily activities such as exercise.Our results provide a promising approach to develop next-generation sweat sensors for real-time and in situ sweat analysis.

A SUFFICIENT CONDITION FOR AFFINE FRAMES WITH MATRIX DILATION

A sufficient condition for affine frame with an arbitrary matrix dilation is presented. It is based on the univariate case by Shi, and generalizes the univariate results of Shi, Casazza and Christensen from one dimension with an arbitrary real number a （a 〉 1） dilation to higher dimension with an arbitrary expansive matrix dilation.

Review of thermal transport and electronic properties of borophene

In recent years, two-dimensional boron sheets （borophene） have been experimentally synthesized and theoretically proposed as a promising conductor or transistor with novel thermal and electronic properties. We first give a general survey of some notable electronic properties of borophene, including the superconductivity and topological characters. We then mainly review the basic approaches, thermal transport, as well as the mechanical properties of borophene with different configurations. This review gives a general understanding of some of the crucial thermal transport and electronic properties of borophene, and also calls for further experimental investigations and applications on certain scientific community.

Stretchable magnesium-air battery based on dual ions conducting hydrogel for intelligent biomedical applications

Flexible and bio-integrated electronics have attracted great attention due to their enormous contributions to personalized medical devices.Power sources,serving as one of the most important components,have been suffering from many problems,including deficient biocompatibility,poor stretchability,and unstable electrical outputs under deformed conditions,which limits the practical applications in flexible and bio-integrated electronics.Here,we reported a fully stretchable magnesium(Mg)–air battery based on dual-ions-conducting hydrogels(SDICH).The high-performance battery enables long-term operation with lighting 120 lighting emitting diodes(LEDs)for over 5 h.Benefiting from the advanced materials and mechanical designs,the battery exhibits stability electrical outputs under stretching,which allows to operate ordinarily under various mechanical deformations without performance decay.Furthermore,the great biocompatibility of the battery offers great opportunity for biomedical applications,which is demonstrated by a self-adaption wound dressing system.The in vitro and in vivo results prove that the self-adaption wound dressing can effectively prevent wound inflammation and promote wound healing.By exploiting thermal feedback mechanics,the system can adjust antibiotic release rate and dosage spontaneously according to the real-time wound conditions.The proposed fully stretchable Mg-air battery and self-adaption wound dressing display great potential in skin-integrated electronics and personalized medicine.

The frame sets of the B-splines

is not completely clear which elements constitute the frame sets of the B-splines currently,but some considerable results have been obtained.In this paper,firstly,the background of frame set is introduced.Secondly,the main progress of the frame sets of the B-splines in the past more than twenty years are reviewed,and particularly the progress for the frame set of the 2 order Bspline and the frame set of the 3 order B-spline are explained,respectively.

The blooming intersection of transcatheter hepatic artery chemoembolization and nanomedicine

Transcatheter hepatic artery chemoembolization(TACE)is a universal treatment for patients with hepatocellular carcinoma(HCC)that inhibits tumor growth by cutting off the blood supply and provides chemotherapeutics locally to the tumor.The strategy of combining TACE formulation with image-guided ablation holds tremendous potential,but patient tolerance and undesired toxicity/immunosuppression remains a challenge.The application of nanotechnology in TACE opens new doors for the treatment of HCC.Strikingly,nanomaterials or nano-drugs dispersed in the TACE formulation can effectively improve the delivery efficiency of drugs by achieving both controlled and continuous release.In addition,the utilization of multifunctional nanoparticles can provide guidance and monitoring for various advanced imaging methods for TACE treatment,and can realize the combination therapy of thermal ablation,microwave ablation,in situ radiotherapy,and other therapies,greatly expanding the therapeutic strategies available for HCC treatment.Here,the current exploration of nanotechnology in TACE of HCC is briefly summarized and the challenges of TACE with nanoformulations for clinical translation are comprehensively discussed.

Orbitally driven giant thermal conductance associated with abnormal strain dependence in hydrogenated graphene-like borophene

Heat energy in solids is carried by phonons and electrons.However,in most two-dimensional(2D)materials,the contribution from electrons to total thermal conduction is much lower than that for phonons.In this work,through first-principles calculations combined with non-equilibrium Green’s function theory,we studied electron and phonon thermal conductance in recently synthesized 2D hydrogen boride.The hexagonal boron network with bridging hydrogen atoms is suggested to exhibit comparable lattice thermal conductance(4.07 nWK−1 nm−2)as graphene(4.1 nWK−1 nm−2),and similar electron thermal conductance(3.6 nWK−1 nm−2),which is almost ten times that of graphene.As a result,total thermal conductance of 2D hydrogen boride is about two-fold of graphene,being the highest value in all known 2D materials.Moreover,tensile strain along the armchair direction leads to an increase in carrier density,significantly increasing electron thermal conductance.The increase in electron thermal conductance offsets the reduction in phonon thermal conductance,contributing to an abnormal increase in thermal conductance.We demonstrate that the high electron density governs extraordinarily high thermal conductance in 2D hydrogen boride,distinctive among 2D materials.

Recent progress of skin-integrated electronics for intelligent sensing

Skin-integrated electronics are a novel type of wearable devices that are mounted on the skin for physiological signal sensing and healthcare monitoring.Their thin,soft,and excellent mechanical properties(stretching,bending,and twisting)allow non-irritating and conformal lamination on the human skin for multifunctional intelligent sensing in real time.In this review,we summarise the recent progress in the intelligent functions of skinintegrated electronics,including physiological sensing,sensory perception,as well as virtual and augmented reality(VR/AR).The detailed applications of these electronics include monitoring physical-and chemical-related health signals,detecting body motions,and serving as the artificial sensory components for visual-,auditory-,and tactilebased sensations.These skin-integrated systems contribute to the development of next-generation e-eyes,e-ears,and e-skin,with a particular focus on materials and structural designs.Research in multidisciplinary materials science,electrical engineering,mechanics,and biomedical engineering will lay a foundation for future improvement in this field of study.

Linear independence of a finite set of time-frequency shifts

This paper introduces an open conjecture in time-frequency analysis on the linear independence of a finite set of time-frequency shifts of a given L2 function.Firstly,background and motivation for the conjecture are provided.Secondly,the main progress of this linear independence in the past twenty five years is reviewed.Finally,the partial results of the high dimensional case and other cases for the conjecture are briefly presented.

Thin,soft,skin-integrated electronics for real-time and wireless detectionof uricacid in sweat

Wearable sweat sensors are gaining significant attention due to their unparalleled potential for noninvasive health monitoring.Sweat,as a kind of body fluid,contains informative physiological indicators that are related to personalized health status.Advances in wearable sweat sampling and routing technologies,flexible,and stretchable materials,and wireless digital technologies have led to the development of integrated sweat sensors that are comfortable,flexible,light,and intelligent.Herein,we report a flexible and integrated wearable device via incorporating a microfluidic system and a sensing chip with skin-integrated electronic format toward in-situ monitoring of uric acid(UA)in sweat that associates with gout,cardiovascular,and renal diseases.The microfluidic system validly realizes the real-time capture perspiration from human skin.The obtained detection range is 5-200μM and the detection limit is 1.79μM,which offers an importance diagnostic method for clinical relevant lab test.The soft and flexible features of the constructed device allows it to be mounted onto nearly anywhere on the body.We tested the sweat UA in diverse subjects and various body locations during exercise,and similar trends were also observed by using a commercial UA assay kit.

Band modification towards high thermoelectric performance of SnSb_(2)Te_(4) with strong anharmonicity driven by cation disorder

As a typical (IV–VI)_(x)(V_(2)VI_(3))_(y) compound, the tetradymite-like layered SnSb_(2)Te_(4) -based compounds have attracted increasing attention in the thermoelectric community owing to the intrinsically low lattice thermal conductivity. Nevertheless, the effect of cations disorder on the inherent physical characteristics remains puzzling, and its inferior Seebeck coefficient is the bottleneck to achieving high thermoelectric performance. In this work, the thermoelectric properties of polycrystalline In_(x)Sn_(1−x)Sb_(2)(Te_(1−y)Se_(y))_(4) (0≤x≤0.1,0≤y≤0.15) samples are comprehensively investigated. In conjunction with the calculated band structure and experimental results, the Seebeck coefficient and power factor are markedly improved after the introduction of indium and selenium, which originates from the combined effects of the emergent resonant states and converged valence bands along with optimal carrier concentration. Additionally, compared with the ordered lattice structure, the disordered cations occupancy in SnSb_(2)Te_(4) further strengthens lattice anharmonicity and reduces phonon group velocity verified by first-principles calculations, securing intrinsically low lattice thermal conductivity. Finally, a record zT value of ∼0.6 at 670 K and an average zT of ∼0.4 between 320 and 720 K are obtained in the In0.1 Sn0.9 Sb2 Te3.4 Se0.6 sample, being one of the highest zT values among SnSb2 Te4 -based materials. This work not only demonstrates that SnSb2 Te4 -based compounds are promising thermoelectric candidates, but also provides guidance for the promotion of thermoelectric performance in a broad temperature range.

Muscle-inspired soft robots based on bilateral dielectric elastomer actuators

Muscle groups perform their functions in the human body via bilateral muscle actuation,which brings bionic inspiration to artificial robot design.Building soft robotic systems with artificial muscles and multiple control dimensions could be an effective means to develop highly controllable soft robots.Here,we report a bilateral actuator with a bilateral deformation function similar to that of a muscle group that can be used for soft robots.To construct this bilateral actuator,a low-cost VHB 4910 dielectric elastomer was selected as the artificial muscle,and polymer films manufactured with specific shapes served as the actuator frame.By end-to-end connecting these bilateral actuators,a gear-shaped 3D soft robot with diverse motion capabilities could be developed,benefiting from adjustable actuation combinations.Lying on the ground with all feet on the ground,a crawling soft robot with dexterous movement along multiple directions was realized.Moreover,the directional steering was instantaneous and efficient.With two feet standing on the ground,it also acted as a rolling soft robot that can achieve bidirectional rolling motion and climbing motion on a 2°slope.Finally,inspired by the orbicularis oris muscle in the mouth,a mouthlike soft robot that could bite and grab objects 5.3 times of its body weight was demonstrated.The bidirectional function of a single actuator and the various combination modes among multiple actuators together allow the soft robots to exhibit diverse functionalities and flexibility,which provides a very valuable reference for the design of highly controllable soft robots.

Accelerated design of lead-free high-performance piezoelectric ceramics with high accuracy via machine learning

The piezoelectric performance serves as the basis for the applications of piezoelectric ceramics.The ability to rapidly and accurately predict the piezoelectric coefficient(d_(33))is of much practical importance for exploring high-performance piezoelectric ceramics.In this work,a data-driven approach combining feature engineering,statistical learning,machine learning(ML),experimental design,and synthesis is trialed to investigate its accuracy in predicting d_(33) of potassium-sodium-niobate(K,Na)NbO_(3),KNN)-based ceramics.The atomic radius(AR),valence electron distance(DV)(Schubert),Martynov-Batsanov electronegativity(EN-MB),and absolute electronegativity(EN)are summarized as the four most representative features in describing d_(33) out of all 27 possible features for the piezoelectric ceramics.These four features contribute greatly to regression learning for predicting d_(33) and classification learning for distinguishing polymorphic phase boundary(PPB).The ML method developed in this work exhibits a high accuracy in predicting d_(33) of the piezoelectric ceramics.An example of KNN combined with 6 mo1%LiNbO_(3)demonstrates d_(33)3 of 184 pC/N,which is highly consistent with the predicted result.This work proposes a novel feature-oriented guideline for accelerating the design of piezoelectric ceramic systems with large d_(33),which is expected to be widely used in other functional materials.