arXiv subjects

Shanshan Su

Publications and source records attributed to Shanshan Su.

15 recordsLinked to original sources

arXiv2026

An in situ self-adaptive hydrogel coating enables seamless neural interfaces via okra mucilage polysaccharide and {\alpha}-helical peptide amphiphiles co-assembly

Long-term stability of neural interfaces is frequently compromised by mechanical mismatch and chronic neuroinflammation, often leading to electrode detachment and signal failure. While hydrogel coatings offer a solution, conventional designs typically rely on exogenous conductive fillers that can sacrifice mechanical flexibility or induce toxicity. Here, we report on a soft neural interface based on the supramolecular co-assembly of a renewable natural polysaccharide, okra mucilage polysaccharide (OMP), and an {\alpha}-helical peptide amphiphiles (APA). The resulting OMP-APA hydrogel (OP gel) exhibits environment-responsive enhancements in bioadhesion and charge-transport capability triggered by physiological pH and electrical stimulation. These properties arise from intrinsic, stimulus-responsive alterations in fibre architecture and orientation, eliminating the need for conductive fillers. Leveraging interfacial liquid-liquid phase separation, we demonstrate the in situ coating of ultra-thin OP-gel coating onto carbon fibre electrodes (CFE). The OP-gel-coated electrodes (OP-CFE) significantly mitigate foreign body responses and glial scarring, enabling stable, high-quality neural recordings in a mouse cortical in vivo model. Our findings provide a versatile strategy for constructing seamless, multifunctional bio-interfaces through supramolecular co-assembly, with broad implications for advancing neural prosthetics and neuroscience research.

physics.bio-ph↗

arXiv2025

New insights into linear maps which are anti-derivable at zero

Let $A$ be a Banach algebra admitting a bounded approximate unit and satisfying property $\mathbb{B}$. Suppose $T: A \rightarrow X$ is a continuous linear map, where $X$ is an essential Banach $A$-bimodule. We prove that the following statements are equivalent: $(i)$ $T$ is anti-derivable at zero (i.e., $a b =0$ in $A$ $\Rightarrow T(b)\cdot a + b\cdot T(a) =0$); $(ii)$ There exist an element $\xi \in X^{**}$ and a linear map (actually a bounded Jordan derivation) $d: A\to X$ satisfying $\xi \cdot a = a \cdot \xi \in X$, $T(a) = d(a) +\xi \cdot a$, and $d(b)\cdot a + b\cdot d(a)= - 2 \xi \cdot (b a),$ for all $a,b\in A$ with $a b =0$. Assuming that $A$ is a C$^*$-algebra we show that a bounded linear mapping $T: A\to X$ is anti-derivable at zero if, and only if, there exist an element $\eta \in X^{**}$ and an anti-derivation $d: A \rightarrow X$ satisfying $\eta \cdot a = a \cdot \eta \in X$, $\eta \cdot [a,b] = 0$ {\rm(}i.e., $L_{\eta}: A \to A$, $L_{\eta} (a) = \eta \cdot a$ vanishes on commutators{\rm)}, and $T(a) = d(a) +\eta \cdot a$, for all $a,b \in A$. The results are also applied for some special operator algebras.

math.OA↗

arXiv2025

A dispersal recolonisation 3D biofilm in vitro model based on co-assembled peptide amphiphiles and clinical wound fluid

Chronic wound infections are sustained by dynamic 3D biofilm cycles involving maturation, dispersal, and recolonisation, yet existing in vitro models fail to reproduce these temporal and structural complexities. Here, we report a strategy that co-assembles a designed protease-inhibitory peptide amphiphile (PA-GF) with patient-derived wound fluid (WF) to reconstruct the complete biofilm life cycle in vitro. The PA-GF sequence incorporates an HWGF motif capable of binding and inhibiting matrix metalloproteinase-9 (MMP-9), thereby preserving the integrity of recolonised biofilms under proteolytic stress. Co-assembling with WF generated a living material that faithfully mimicked the biochemical and mechanical microenvironment of chronic wounds, supporting the formation of stable 3D biofilms capable of dispersal and recolonisation. Furthermore, we established a controllable polymicrobial infection model and validated its translational relevance through antibiotic susceptibility profiling and spatial microbiological analyses. Notably, the antibiotic response patterns of the PA/WF-derived biofilms closely mirrored those observed in a rat wound infection in vivo model. Collectively, our findings demonstrate that co-assembling living materials can recapitulate the nutritional composition, 3D architecture, and recolonisation dynamics of in vivo infectious biofilms, offering a physiologically relevant and customisable platform for investigating chronic wound infections and accelerating anti-biofilm drug discovery.

physics.med-ph↗

arXiv2025

Mastering energy landscapes via liquid liquid phase separation to program active supramolecular coassembly from the nano to macro scale

The energy landscape dictates pathways and outcomes in supramolecular selfassembly, yet harnessing it from the nano to the macro scales remains a major challenge. Here, we demonstrate liquid liquid phase separation (LLPS) as a powerful tool to navigate and engineer the energy landscapes of coassembly systems comprising disordered proteins and peptides. We quantitatively map the energy barriers and transition states governing structural transitions, enabling predictive on off control of assembly and hierarchical order from nano to macro scales. By integrating supramolecular biofabrication, we achieve spatially organized architectures with life like non equilibrium behaviour. Crucially, assembly stability and scalable selfsorting are shown to depend on accessing minimum energy states, regardless of whether the co assembled structures are disordered or ordered. This work establishes energy landscape mediation via LLPS as a general framework for designing lifelike, hierarchically structured materials.

cond-mat.soft↗

arXiv2025

Uniqueness of Hahn--Banach extensions and inner ideals in real C$^$-algebras and real JB$^$-triples

We show that every closed (resp., weak$^*$-closed) inner ideal $I$ of a real JB$^*$-triple (resp. a real JBW$^*$-triple) $E$ is Hahn--Banach smooth (resp., weak$^*$-Hahn--Banach smooth). Contrary to what is known for complex JB$^*$-triples, being (weak$^*$-)Hahn--Banach smooth does not characterise (weak$^*$-)closed inner ideals in real JB(W)$^*$-triples. We prove here that a closed (resp., weak$^*$-closed) subtriple of a real JB$^*$-triple (resp., a real JBW$^*$-triple) is Hahn-Banach smooth (resp., weak$^*$-Hahn-Banach smooth) if, and only if, it is a hereditary subtriple. If we assume that $E$ is a reduced and atomic JBW$^*$-triple, every weak$^*$-closed subtriple of $E$ which is also weak$^*$-Hahn-Banach smooth is an inner ideal.\smallskip In case that $C$ is the realification of a complex Cartan factor or a non-reduced real Cartan factor, we show that every weak$^*$-closed subtriple of $C$ which is weak$^*$-Hahn-Banach smooth and has rank $\geq 2$ is an inner ideal. The previous conclusions are finally combined to prove the following: Let $I$ be a closed subtriple of a real JB$^*$-triple $E$ satisfying the following hypotheses: $(a)$ $I^*$ is separable. $(b)$ $I$ is weak$^*$-Hahn-Banach smooth. $(c)$ The projection of $I^{**}$ onto each real or complex Cartan factor summand in the atomic part of $E^{**}$ is zero or has rank $\geq 2$. Then $I$ is an inner ideal of $E$.

math.OA↗

arXiv2025

De novo design of alpha-helical peptide amphiphiles repairing fragmented collagen type I via supramolecular co-assembly

The hierarchical triple-helix structure of collagen type I, Col I, is essential for extracellular matrix support and integrity. However, current reconstruction strategies face challenges such as chain mismatch, preventing proper fibril formation. Here, we report a supramolecular co-assembly strategy using a de novo-designed alpha-helical peptide amphiphile (APA) of just seven amino acids. The APA features a hydrophobic palmitic acid tail, which stabilizes the helical structure and promotes co-assembly upon interaction with complementary molecular structures. This minimal design enables selective recognition of fragmented collagen (FC), restoring triple-helix conformation and guiding fibre formation. We applied this mechanism to engineer FC-rich nanofat (NF) into a mechanically reinforced biomaterial. Integration of APA-NF with coaxial 3D printing enabled spatial control of structure and function. In a porcine model, this platform enhanced in situ vascularized adipose tissue regeneration. Our results demonstrate that hierarchical reconstruction of collagen via peptide-guided supramolecular assembly offers a promising strategy for soft tissue repair.

physics.chem-ph↗

arXiv2024

Maps preserving the truncation of triple products on Cartan factors

Let $\{C_i\}_{i\in \Gamma_1},$ and $\{D_j\}_{j\in \Gamma_2},$ be two families of Cartan factors such that all of them have dimension at least $2$, and consider the atomic JBW$^*$-triples $A=\bigoplus\limits_{i\in \Gamma_1}^{\ell_{\infty}} C_i$ and $B=\bigoplus\limits_{j\in \Gamma_2}^{\ell_{\infty}} D_j$. Let $\Delta :A \to B$ be a {\rm(}non-necessarily linear nor continuous{\rm)} bijection preserving the truncation of triple products in both directions, that is, $$\begin{aligned} \boxed{a \mbox{ is a truncation of } \{b,c,b\}} \Leftrightarrow \boxed{\Delta(a) \mbox{ is a truncation of } \{\Delta(b),\Delta(c),\Delta(b)\}} \end{aligned}$$ Assume additionally that the restriction of $\Delta$ to each rank-one Cartan factor in $A$, if any, is a continuous mapping. Then we show that $\Delta$ is an isometric real linear triple isomorphism. We also study some general properties of bijections preserving the truncation of triple products in both directions between general JB$^*$-triples.

math.OA↗

arXiv2024

M-ideals in real operator algebras

In a recent paper we showed that a subspace of a real JBW*-triple is an M-summand if and only if it is a weak*-closed triple ideal. As a consequence, M-ideals of real JB*-triples, including real C*-algebras, real JB*-algebras and real TROs, correspond to norm-closed triple ideals. In the present paper we extend this result to (possibly non-selfadjoint) real operator algebras and Jordan operator algebras, where the argument is necessarily different. We also give simple characterizations of one-sided M-ideals in real operator algebras, and give some applications to that theory.

math.OA↗

arXiv2024

On the equivalence of all notions of generalized derivations whose domain is a C$^{\ast}$-algebra

Let $\mathcal{M}$ be a Banach bimodule over an associative Banach algebra $\mathcal{A}$, and let $F: \mathcal{A}\to \mathcal{M}$ be a linear mapping. Three main uses of the term \emph{generalized derivation} are identified in the available literature, namely, ($\checkmark$) $F$ is a generalized derivation of the first type if there exists a derivation $ d : \mathcal{A}\to \mathcal{M}^{**}$ satisfying $F(a b ) = F(a) b + a d(b),$ for all $a,b\in \mathcal{A}$. ($\checkmark$) $F$ is a generalized derivation of the second type if there exists an element $\xi\in \mathcal{M}^{**}$ satisfying $F(a b ) = F(a) b + a F(b) - a \xi b,$ for all $a,b\in \mathcal{A}$. ($\checkmark$) $F$ is a generalized derivation of the third type if there exist two (non-necessarily linear) mappings $G,H : \mathcal{A}\to \mathcal{M}$ satisfying $F(a b ) = G(a) b + a H(b),$ for all $a,b\in \mathcal{A}$. These three types of maps are not, in general, equivalent. Although the first two notions are well studied when $\mathcal{A}$ is a C$^*$-algebra, their connections with the third one have not yet been explored. In this note we prove that every generalized derivation of the third type from a C$^*$-algebra $\mathcal{A}$ to a Banach $\mathcal{A}$-bimodule $\mathcal{M}$ is automatically continuous. We also show that every (continuous) generalized derivation of the third type from $\mathcal{A}$ to $\mathcal{M}$ is a generalized derivation of the first and second type. Consequently, the three notions coincide in this case. We also explore some concepts of generalized Jordan derivations on a C$^*$-algebra and establish some continuity properties for them.

math.OA↗

arXiv2024

$M$-ideals, yet again: the case of real JB$^*$-triples

We prove that a subspace of a real JBW$^*$-triple is an $M$-summand if and only if it is a weak$^*$-closed triple ideal. As a consequence, $M$-ideals of real JB$^*$-triples correspond to norm-closed triple ideals. As in the setting of complex JB$^*$-triples, a geometric property is characterized in purely algebraic terms. This is a newfangled treatment of the classical notion of $M$-ideal in the real setting by a fully new approach due to the unfeasibility of the known arguments in the setting of complex C$^*$-algebras and JB$^*$-triples. The results in this note also provide a full characterization of all $M$-ideals in real C$^*$-algebras, real JB$^*$-algebras and real TROs.

math.OA↗

arXiv2022

Zero product determined Banach algebras

Let $\mathcal{L}$ be a completely distributive commutative subspace lattice or a subspace lattice with two atoms, we use a unified approach to study the derivations, homomorphisms on $\mathrm{Alg} \mathcal{L}$. We verify that the multiplier algebra of $\mathrm{Alg} \mathcal{L}\cap \mathcal{K}(\mathcal{H})$ is isomorphic to $\mathrm{Alg} \mathcal{L}$ and $\mathrm{Alg} \mathcal{L}$ is zero product determined. For $T$ in $M_{n}(\mathbb{C})$, $n\geq 2$, we show that $\mathcal{A}_{T}$ is zero product determined if and only if every local derivation from $\mathcal{A}_{T}$ into any Banach $\mathcal{A}_{T}$-bimodule is a derivation. In addition, we establish some equivalent conditions for an algebra to be zero product determined. For countable dimensional locally matrix algebras and triangular UHF algebras, we also show that they are zero Lie product determined.

math.FA↗

arXiv2020

Stacking enabled strong coupling of atomic motion to interlayer excitons in van der Waals heterojunction photodiodes

We reveal stacking-induced strong coupling between atomic motion and interlayer excitons through photocurrent measurements of WSe$_2$/MoSe$_2$ heterojunction photodiodes. Strong coupling manifests as pronounced periodic sidebands in the photocurrent spectrum in frequency windows close to the interlayer exciton resonances. The sidebands, which repeat over large swathes of the interlayer exciton photocurrent spectrum, occur in energy increments corresponding directly to a prominent vibrational mode of the heterojunction. Such periodic patterns, together with interlayer photoconductance oscillations, vividly demonstrate the emergence of extraordinarily strong exciton-phonon coupling - and its impact on interlayer excitations - in stack-engineered van der Waals heterostructure devices. Our results establish photocurrent spectroscopy as a powerful tool for interrogating vibrational coupling to interlayer excitons and suggest an emerging strategy to control vibronic physics in the solid-state.

cond-mat.mes-hall↗

arXiv2016

Graphene Contacts to a HfSe2/SnS2 Heterostructure

Placing graphene on SnS2 results in significant charge transfer, on the order of 10^13/cm^2, from the graphene to the SnS2, and the charge transfer results in a negative Schottky barrier contact for electron injection from the graphene into the SnS2 conduction band. However, due to the s-px,y composition of the SnS2 conduction band, the coupling between the SnS2 and the graphene is relatively weak. A third layer, HfSe2, placed between the SnS2 and the graphene, serves as a matrix element matching layer, since it has strong coupling to both the graphene and the SnS2. It increases the coupling to the graphene by a factor of 10, and it has little effect on the negative Schottky barrier height, since the conduction band wavefucntion of the SnS2 / HfSe2 is a coherent superposition of the orbitals from the two individual layers, such that there is no energy barrier for an electron to move between the two layers. This paper first investigates the electronic properties of the heterostructure bilayer SnS2 / HfSe2 in the presence of an applied vertical electric field, and then it investigates the trilayer systems of BN / SnS2 / HfSe2 and graphene / SnS2 / HfSe2. A tunneling Hamiltonian estimate of the the contact resistance of the graphene to the SnS2 / HfSe2 heterostructure indicates an excellent low-resistance contact.

cond-mat.mtrl-sci↗

arXiv2016

Interlayer Resistance of Misoriented MoS2

Interlayer misorientation in transition metal dichalcogenides alters the interlayer distance, the electronic band structure, and the vibrational modes, but, its effect on the interlayer resistance is not known. This work analyzes the coherent interlayer resistance of misoriented 2H-MoS2 for low energy electrons and holes as a function of the misorientation angle. The electronic interlayer resistance monotonically increases with the supercell lattice constant by several orders of magnitude similar to that of misoriented bilayer graphene. The large hole coupling gives low interlayer hole resistance that weakly depends on the misorientation angle. Interlayer rotation between an n-type region and a p-type region will suppress the electron current with little effect on the hole current. We estimate numerical bounds and explain the results in terms of the orbital composition of the bands at high symmetry points. Density functional theory calculations provide the interlayer coupling used in both a tunneling Hamiltonian and a non-equilibrium Green function calculation of the resistivity.

cond-mat.mtrl-sci↗

arXiv2015

Proximity induced quantum anomalous Hall effect in graphene/EuO hetero-structures

In a heterostructure of graphene and the ferromagnetic insulator EuO, the Eu atoms induce proximity exchange and inter-valley interactions in the graphene layer. Constrained by the lattice symmetries, and guided by ab initio calculations, a model Hamiltonian is constructed that describes the low-energy bands. Band parameters such as proximity induced exchange splitting, spin orbit coupling, and inter-valley interaction are determined. Calculations of the Chern number identify the conditions under which the hetero-structures exhibit topologically non-trivial bands that give rise to the quantum anomalous Hall effect with a Hall conductivity of $σ_{xy} = 2 e^2/h$.

cond-mat.mtrl-sci↗