@misc{13060, abstract = {Coinfections with multiple pathogens can result in complex within-host dynamics affecting virulence and transmission. Whilst multiple infections are intensively studied in solitary hosts, it is so far unresolved how social host interactions interfere with pathogen competition, and if this depends on coinfection diversity. We studied how the collective disease defenses of ants – their social immunity ­– influence pathogen competition in coinfections of same or different fungal pathogen species. Social immunity reduced virulence for all pathogen combinations, but interfered with spore production only in different-species coinfections. Here, it decreased overall pathogen sporulation success, whilst simultaneously increasing co-sporulation on individual cadavers and maintaining a higher pathogen diversity at the community-level. Mathematical modeling revealed that host sanitary care alone can modulate competitive outcomes between pathogens, giving advantage to fast-germinating, thus less grooming-sensitive ones. Host social interactions can hence modulate infection dynamics in coinfected group members, thereby altering pathogen communities at the host- and population-level.}, author = {Milutinovic, Barbara and Stock, Miriam and Grasse, Anna V and Naderlinger, Elisabeth and Hilbe, Christian and Cremer, Sylvia}, publisher = {Dryad}, title = {{Social immunity modulates competition between coinfecting pathogens}}, doi = {10.5061/DRYAD.CRJDFN318}, year = {2020}, } @misc{13065, abstract = {Domestication is a human-induced selection process that imprints the genomes of domesticated populations over a short evolutionary time scale, and that occurs in a given demographic context. Reconstructing historical gene flow, effective population size changes and their timing is therefore of fundamental interest to understand how plant demography and human selection jointly shape genomic divergence during domestication. Yet, the comparison under a single statistical framework of independent domestication histories across different crop species has been little evaluated so far. Thus, it is unclear whether domestication leads to convergent demographic changes that similarly affect crop genomes. To address this question, we used existing and new transcriptome data on three crop species of Solanaceae (eggplant, pepper and tomato), together with their close wild relatives. We fitted twelve demographic models of increasing complexity on the unfolded joint allele frequency spectrum for each wild/crop pair, and we found evidence for both shared and species-specific demographic processes between species. A convergent history of domestication with gene-flow was inferred for all three species, along with evidence of strong reduction in the effective population size during the cultivation stage of tomato and pepper. The absence of any reduction in size of the crop in eggplant stands out from the classical view of the domestication process; as does the existence of a “protracted period” of management before cultivation. Our results also suggest divergent management strategies of modern cultivars among species as their current demography substantially differs. Finally, the timing of domestication is species-specific and supported by the few historical records available.}, author = {Arnoux, Stephanie and Fraisse, Christelle and Sauvage, Christopher}, publisher = {Dryad}, title = {{VCF files of synonymous SNPs related to: Genomic inference of complex domestication histories in three Solanaceae species}}, doi = {10.5061/DRYAD.Q2BVQ83HD}, year = {2020}, } @misc{13070, abstract = {This dataset comprises all data shown in the figures of the submitted article "Surpassing the resistance quantum with a geometric superinductor". Additional raw data are available from the corresponding author on reasonable request.}, author = {Peruzzo, Matilda and Trioni, Andrea and Hassani, Farid and Zemlicka, Martin and Fink, Johannes M}, publisher = {Zenodo}, title = {{Surpassing the resistance quantum with a geometric superinductor}}, doi = {10.5281/ZENODO.4052882}, year = {2020}, } @misc{13071, abstract = {This dataset comprises all data shown in the plots of the main part of the submitted article "Bidirectional Electro-Optic Wavelength Conversion in the Quantum Ground State". Additional raw data are available from the corresponding author on reasonable request.}, author = {Hease, William J and Rueda Sanchez, Alfredo R and Sahu, Rishabh and Wulf, Matthias and Arnold, Georg M and Schwefel, Harald and Fink, Johannes M}, publisher = {Zenodo}, title = {{Bidirectional electro-optic wavelength conversion in the quantum ground state}}, doi = {10.5281/ZENODO.4266025}, year = {2020}, } @misc{13073, abstract = {The Mytilus complex of marine mussel species forms a mosaic of hybrid zones, found across temperate regions of the globe. This allows us to study "replicated" instances of secondary contact between closely-related species. Previous work on this complex has shown that local introgression is both widespread and highly heterogeneous, and has identified SNPs that are outliers of differentiation between lineages. Here, we developed an ancestry-informative panel of such SNPs. We then compared their frequencies in newly-sampled populations, including samples from within the hybrid zones, and parental populations at different distances from the contact. Results show that close to the hybrid zones, some outlier loci are near to fixation for the heterospecific allele, suggesting enhanced local introgression, or the local sweep of a shared ancestral allele. Conversely, genomic cline analyses, treating local parental populations as the reference, reveal a globally high concordance among loci, albeit with a few signals of asymmetric introgression. Enhanced local introgression at specific loci is consistent with the early transfer of adaptive variants after contact, possibly including asymmetric bi-stable variants (Dobzhansky-Muller incompatibilities), or haplotypes loaded with fewer deleterious mutations. Having escaped one barrier, however, these variants can be trapped or delayed at the next barrier, confining the introgression locally. These results shed light on the decay of species barriers during phases of contact.}, author = {Simon, Alexis and Fraisse, Christelle and El Ayari, Tahani and Liautard-Haag, Cathy and Strelkov, Petr and Welch, John and Bierne, Nicolas}, publisher = {Dryad}, title = {{How do species barriers decay? concordance and local introgression in mosaic hybrid zones of mussels}}, doi = {10.5061/DRYAD.R4XGXD29N}, year = {2020}, } @article{13341, abstract = {Scanning nanoscale superconducting quantum interference devices (nanoSQUIDs) are of growing interest for highly sensitive quantitative imaging of magnetic, spintronic, and transport properties of low-dimensional systems. Utilizing specifically designed grooved quartz capillaries pulled into a sharp pipette, we have fabricated the smallest SQUID-on-tip (SOT) devices with effective diameters down to 39 nm. Integration of a resistive shunt in close proximity to the pipette apex combined with self-aligned deposition of In and Sn, have resulted in SOT with a flux noise of 42 n$\Phi_0$Hz$^{-1/2}$, yielding a record low spin noise of 0.29 $\mu_B$Hz$^{-1/2}$. In addition, the new SOTs function at sub-Kelvin temperatures and in high magnetic fields of over 2.5 T. Integrating the SOTs into a scanning probe microscope allowed us to image the stray field of a single Fe$_3$O$_4$ nanocube at 300 mK. Our results show that the easy magnetization axis direction undergoes a transition from the (111) direction at room temperature to an in-plane orientation, which could be attributed to the Verwey phase transition in Fe$_3$O$_4$.}, author = {Anahory, Y. and Naren, H. R. and Lachman, E. O. and Sinai, S. Buhbut and Uri, A. and Embon, L. and Yaakobi, E. and Myasoedov, Y. and Huber, M. E. and Klajn, Rafal and Zeldov, E.}, issn = {2040-3372}, journal = {Nanoscale}, number = {5}, pages = {3174--3182}, publisher = {Royal Society of Chemistry}, title = {{SQUID-on-tip with single-electron spin sensitivity for high-field and ultra-low temperature nanomagnetic imaging}}, doi = {10.1039/C9NR08578E}, volume = {12}, year = {2020}, } @article{21083, abstract = {Helically folded aromatic oligoamide foldamers have a size and geometrical parameters very distinct from those of α‐helices and are not obvious candidates for α‐helix mimicry. Nevertheless, they offer multiple sites for attaching side chains. It was found that some arrays of side chains at the surface of an aromatic helix make it possible to mimic extended α‐helical surfaces. Synthetic methods were developed to produce quinoline monomers suitably functionalized for solid phase synthesis. A dodecamer was prepared. Its crystal structure validated the initial design and showed helix bundling involving the α‐helix‐like interface. These results open up new uses of aromatic helices to recognize protein surfaces and to program helix bundling in water.}, author = {Zwillinger, Márton and Reddy, Post Sai and Wicher, Barbara and Mandal, Pradeep K and Csékei, Márton and Fischer, Lucile and Kotschy, András and Huc, Ivan}, issn = {1521-3765}, journal = {Chemistry – A European Journal}, number = {72}, pages = {17366--17370}, publisher = {Wiley}, title = {{Aromatic foldamer helices as α‐helix extended surface mimetics}}, doi = {10.1002/chem.202004064}, volume = {26}, year = {2020}, } @article{21084, abstract = {Self-assembly is a powerful method to obtain large discrete functional molecular architectures. When using a single building block, self-assembly generally yields symmetrical objects in which all the subunits relate similarly to their neighbours. Here we report the discovery of a family of self-constructing cyclic macromolecules with stable folded conformations of low symmetry, which include some with a prime number (13, 17 and 23) of units, despite being formed from a single component. The formation of these objects amounts to the production of polymers with a perfectly uniform length. Design rules for the spontaneous emergence of such macromolecules include endowing monomers with a strong potential for non-covalent interactions that remain frustrated in competing entropically favoured yet conformationally restrained smaller cycles. The process can also be templated by a guest molecule that itself has an asymmetrical structure, which paves the way to molecular imprinting techniques at the level of single polymer chains.}, author = {Pappas, Charalampos G. and Mandal, Pradeep K and Liu, Bin and Kauffmann, Brice and Miao, Xiaoming and Komáromy, Dávid and Hoffmann, Waldemar and Manz, Christian and Chang, Rayoon and Liu, Kai and Pagel, Kevin and Huc, Ivan and Otto, Sijbren}, issn = {1755-4349}, journal = {Nature Chemistry}, number = {12}, pages = {1180--1186}, publisher = {Springer Nature}, title = {{Emergence of low-symmetry foldamers from single monomers}}, doi = {10.1038/s41557-020-00565-2}, volume = {12}, year = {2020}, } @article{21085, abstract = {Foldamers combining aliphatic and aromatic main-chain units often produce atypical structures that cannot easily be accessed from purely aromatic or aliphatic sequences. We report solid-state evidence that sequences comprising α-amino acids and quinoline-based monomers adopt conformations that combine the folding propensities of both components. Foldamers 2 and 3 having an XQQ repeat motif (X=α-amino acid, Q=quinoline) were synthesized. Crystals of 2 (X=Phe, Q with an anionic side chain) obtained from water revealed an aromatic helix where amide groups belonging to the α-amino acids created a hydrogen-bond array typical of peptidic helices. Crystals of 3 (X=Ser, Q with a lipophilic side chain) obtained from organic solvents revealed a helix-turn-helix structure in which α-amino acid side chains interfere with main-chain hydrogen bonding. High sequence-dependency of the conformation is typical of peptides but is shown here to include aromatic folding features.}, author = {Hu, Xiaobo and Mandal, Pradeep K and Kauffmann, Brice and Huc, Ivan}, issn = {2192-6506}, journal = {ChemPlusChem}, number = {7}, pages = {1580--1586}, publisher = {Wiley}, title = {{Hybrid sequences that express both aromatic amide and α‐peptidic folding features}}, doi = {10.1002/cplu.202000416}, volume = {85}, year = {2020}, } @article{21525, abstract = {We present a novel design for an ultracompact, passive light source capable of generating ultraviolet and X-ray radiation, based on the interaction of free electrons with the magnetic near-field of a ferromagnet. Our design is motivated by recent advances in the fabrication of nanostructures, which allow the confinement of large magnetic fields at the surface of ferromagnetic nanogratings. Using ab initio simulations and a complementary analytical theory, we show that highly directional, tunable, monochromatic radiation at high frequencies could be produced from relatively low-energy electrons within a tabletop design. The output frequency is tunable in the extreme ultraviolet to hard X-ray range via electron kinetic energies from 1 keV to 5 MeV and nanograting periods from 1 μm to 5 nm. The proposed radiation source can achieve the tunability and monochromaticity of current free-electron-driven sources (free-electron lasers, synchrotrons, and laser-driven undulators), yet with a significantly reduced scale, cost, and complexity. Our design could help realize the next generation of tabletop or on-chip X-ray sources.}, author = {Fisher, Sophie and Roques-Carmes, Charles and Rivera, Nicholas and Wong, Liang Jie and Kaminer, Ido and Soljačić, Marin}, issn = {2330-4022}, journal = {ACS Photonics}, keywords = {X-ray sources, free electrons, nanostructure, undulator, synchrotron, free-electron laser}, number = {5}, pages = {1096--1103}, publisher = {American Chemical Society }, title = {{Monochromatic X-ray source based on scattering from a magnetic nanoundulator}}, doi = {10.1021/acsphotonics.0c00121}, volume = {7}, year = {2020}, } @article{21539, abstract = {The inability of conventional electronic architectures to efficiently solve large combinatorial problems motivates the development of novel computational hardware. There has been much effort toward developing application-specific hardware across many different fields of engineering, such as integrated circuits, memristors, and photonics. However, unleashing the potential of such architectures requires the development of algorithms which optimally exploit their fundamental properties. Here, we present the Photonic Recurrent Ising Sampler (PRIS), a heuristic method tailored for parallel architectures allowing fast and efficient sampling from distributions of arbitrary Ising problems. Since the PRIS relies on vector-to-fixed matrix multiplications, we suggest the implementation of the PRIS in photonic parallel networks, which realize these operations at an unprecedented speed. The PRIS provides sample solutions to the ground state of Ising models, by converging in probability to their associated Gibbs distribution. The PRIS also relies on intrinsic dynamic noise and eigenvalue dropout to find ground states more efficiently. Our work suggests speedups in heuristic methods via photonic implementations of the PRIS.}, author = {Roques-Carmes, Charles and Shen, Yichen and Zanoci, Cristian and Prabhu, Mihika and Atieh, Fadi and Jing, Li and Dubček, Tena and Mao, Chenkai and Johnson, Miles R. and Čeperić, Vladimir and Joannopoulos, John D. and Englund, Dirk and Soljačić, Marin}, issn = {2041-1723}, journal = {Nature Communications}, publisher = {Springer Nature}, title = {{Heuristic recurrent algorithms for photonic Ising machines}}, doi = {10.1038/s41467-019-14096-z}, volume = {11}, year = {2020}, } @article{21554, abstract = {Recent progress in artificial intelligence is largely attributed to the rapid development of machine learning, especially in the algorithm and neural network models. However, it is the performance of the hardware, in particular the energy efficiency of a computing system that sets the fundamental limit of the capability of machine learning. Data-centric computing requires a revolution in hardware systems, since traditional digital computers based on transistors and the von Neumann architecture were not purposely designed for neuromorphic computing. A hardware platform based on emerging devices and new architecture is the hope for future computing with dramatically improved throughput and energy efficiency. Building such a system, nevertheless, faces a number of challenges, ranging from materials selection, device optimization, circuit fabrication and system integration, to name a few. The aim of this Roadmap is to present a snapshot of emerging hardware technologies that are potentially beneficial for machine learning, providing the Nanotechnology readers with a perspective of challenges and opportunities in this burgeoning field.}, author = {Berggren, Karl and Xia, Qiangfei and Likharev, Konstantin K and Strukov, Dmitri B and Jiang, Hao and Mikolajick, Thomas and Querlioz, Damien and Salinga, Martin and Erickson, John R and Pi, Shuang and Xiong, Feng and Lin, Peng and Li, Can and Chen, Yu and Xiong, Shisheng and Hoskins, Brian D and Daniels, Matthew W and Madhavan, Advait and Liddle, James A and McClelland, Jabez J and Yang, Yuchao and Rupp, Jennifer and Nonnenmann, Stephen S and Cheng, Kwang-Ting and Gong, Nanbo and Lastras-Montaño, Miguel Angel and Talin, A Alec and Salleo, Alberto and Shastri, Bhavin J and de Lima, Thomas Ferreira and Prucnal, Paul and Tait, Alexander N and Shen, Yichen and Meng, Huaiyu and Roques-Carmes, Charles and Cheng, Zengguang and Bhaskaran, Harish and Jariwala, Deep and Wang, Han and Shainline, Jeffrey M and Segall, Kenneth and Yang, J Joshua and Roy, Kaushik and Datta, Suman and Raychowdhury, Arijit}, issn = {1361-6528}, journal = {Nanotechnology}, number = {1}, publisher = {IOP Publishing}, title = {{Roadmap on emerging hardware and technology for machine learning}}, doi = {10.1088/1361-6528/aba70f}, volume = {32}, year = {2020}, } @inproceedings{21621, abstract = {We show that nanophotonic structures enable the possibility of realizing lasers based on stimulated emission by free electrons. The associated threshold beam currents are in the nanoampere range, and could be realized in electron microscopes.}, author = {Rivera, Nicholas and Roques-Carmes, Charles and Kaminer, Ido and Soljačić, Marin}, booktitle = {Conference on Lasers and Electro-Optics}, location = {Washington, DC, United States}, publisher = {Optica Publishing Group}, title = {{Toward nanophotonic free-electron lasers}}, doi = {10.1364/cleo_qels.2020.fm2q.3}, year = {2020}, } @article{21637, abstract = {We demonstrate new axisymmetric inverse-design techniques that can solve problems radically different from traditional lenses, including reconfigurable lenses (that shift a multi-frequency focal spot in response to refractive-index changes) and widely separated multi-wavelength lenses (λ = 1 µm and 10 µm). We also present experimental validation for an axisymmetric inverse-designed monochrome lens in the near-infrared fabricated via two-photon polymerization. Axisymmetry allows fullwave Maxwell solvers to be scaled up to structures hundreds or even thousands of wavelengths in diameter before requiring domain-decomposition approximations, while multilayer topology optimization with ∼105 degrees of freedom can tackle challenging design problems even when restricted to axisymmetric structures.}, author = {Christiansen, Rasmus E. and Lin, Zin and Roques-Carmes, Charles and Salamin, Yannick and Kooi, Steven E. and Joannopoulos, John D. and Soljačić, Marin and Johnson, Steven G.}, issn = {1094-4087}, journal = {Optics Express}, number = {23}, pages = {33854--33868}, publisher = {Optica Publishing Group}, title = {{Fullwave Maxwell inverse design of axisymmetric, tunable, and multi-scale multi-wavelength metalenses}}, doi = {10.1364/oe.403192}, volume = {28}, year = {2020}, } @article{21640, abstract = {Conventional computing architectures have no known efficient algorithms for combinatorial optimization tasks such as the Ising problem, which requires finding the ground state spin configuration of an arbitrary Ising graph. Physical Ising machines have recently been developed as an alternative to conventional exact and heuristic solvers; however, these machines typically suffer from decreased ground state convergence probability or universality for high edge- density graphs or arbitrary graph weights, respectively. We experimentally demonstrate a proof-of-principle integrated nanophotonic recurrent Ising sampler (INPRIS), using a hybrid scheme combining electronics and silicon-on-insulator photonics, that is capable of converging to the ground state of various four-spin graphs with high probability. The INPRIS results indicate that noise may be used as a resource to speed up the ground state search and to explore larger regions of the phase space, thus allowing one to probe noise-dependent physical observables. Since the recurrent pho- tonic transformation that our machine imparts is a fixed function of the graph problem and therefore compatible with optoelectronic architectures that support GHz clock rates (such as passive or non-volatile photonic circuits that do not require reprogramming at each iteration), this work suggests the potential for future systems that could achieve orders- of-magnitude speedups in exploring the solution space of combinatorially hard problems. }, author = {Prabhu, Mihika and Roques-Carmes, Charles and Shen, Yichen and Harris, Nicholas and Jing, Li and Carolan, Jacques and Hamerly, Ryan and Baehr-Jones, Tom and Hochberg, Michael and Čeperić, Vladimir and Joannopoulos, John D. and Englund, Dirk R. and Soljačić, Marin}, issn = {2334-2536}, journal = {Optica}, number = {5}, pages = {551--558}, publisher = {Optica Publishing Group}, title = {{Accelerating recurrent Ising machines in photonic integrated circuits}}, doi = {10.1364/optica.386613}, volume = {7}, year = {2020}, } @article{21642, abstract = {By codesigning a metaoptical front end in conjunction with an image‐processing back end, we demonstrate noise sensitivity and compactness substantially superior to either an optics‐only or a computation‐only approach, illustrated by two examples: subwavelength imaging and reconstruction of the full polarization coherence matrices of multiple light sources. Our end‐to‐end inverse designs couple the solution of the full Maxwell equations—exploiting all aspects of wave physics arising in subwavelength scatterers—with inverse‐scattering algorithms in a single large‐scale optimization involving degrees of freedom. The resulting structures scatter light in a way that is radically different from either a conventional lens or a random microstructure, and suppress the noise sensitivity of the inverse‐scattering computation by several orders of magnitude. Incorporating the full wave physics is especially crucial for detecting spectral and polarization information that is discarded by geometric optics and scalar diffraction theory.}, author = {Lin, Zin and Roques-Carmes, Charles and Pestourie, Raphaël and Soljačić, Marin and Majumdar, Arka and Johnson, Steven G.}, issn = {2192-8614}, journal = {Nanophotonics}, keywords = {computational imaging, end-to-end photonic inverse design, inverse scattering, meta-optics, polarimetry}, number = {3}, pages = {1177--1187}, publisher = {Wiley}, title = {{End‐to‐end nanophotonic inverse design for imaging and polarimetry}}, doi = {10.1515/nanoph-2020-0579}, volume = {10}, year = {2020}, } @article{13361, abstract = {In nature, light is harvested by photoactive proteins to drive a range of biological processes, including photosynthesis, phototaxis, vision, and ultimately life. Bacteriorhodopsin, for example, is a protein embedded within archaeal cell membranes that binds the chromophore retinal within its hydrophobic pocket. Exposure to light triggers regioselective photoisomerization of the confined retinal, which in turn initiates a cascade of conformational changes within the protein, triggering proton flux against the concentration gradient, providing the microorganisms with the energy to live. We are inspired by these functions in nature to harness light energy using synthetic photoswitches under confinement. Like retinal, synthetic photoswitches require some degree of conformational flexibility to isomerize. In nature, the conformational change associated with retinal isomerization is accommodated by the structural flexibility of the opsin host, yet it results in steric communication between the chromophore and the protein. Similarly, we strive to design systems wherein isomerization of confined photoswitches results in steric communication between a photoswitch and its confining environment. To achieve this aim, a balance must be struck between molecular crowding and conformational freedom under confinement: too much crowding prevents switching, whereas too much freedom resembles switching of isolated molecules in solution, preventing communication. In this Account, we discuss five classes of synthetic light-switchable compounds—diarylethenes, anthracenes, azobenzenes, spiropyrans, and donor–acceptor Stenhouse adducts—comparing their behaviors under confinement and in solution. The environments employed to confine these photoswitches are diverse, ranging from planar surfaces to nanosized cavities within coordination cages, nanoporous frameworks, and nanoparticle aggregates. The trends that emerge are primarily dependent on the nature of the photoswitch and not on the material used for confinement. In general, we find that photoswitches requiring less conformational freedom for switching are, as expected, more straightforward to isomerize reversibly under confinement. Because these compounds undergo only small structural changes upon isomerization, however, switching does not propagate into communication with their environment. Conversely, photoswitches that require more conformational freedom are more challenging to switch under confinement but also can influence system-wide behavior. Although we are primarily interested in the effects of geometric constraints on photoswitching under confinement, additional effects inevitably emerge when a compound is removed from solution and placed within a new, more crowded environment. For instance, we have found that compounds that convert to zwitterionic isomers upon light irradiation often experience stabilization of these forms under confinement. This effect results from the mutual stabilization of zwitterions that are brought into close proximity on surfaces or within cavities. Furthermore, photoswitches can experience preorganization under confinement, influencing the selectivity and efficiency of their photoreactions. Because intermolecular interactions arising from confinement cannot be considered independently from the effects of geometric constraints, we describe all confinement effects concurrently throughout this Account.}, author = {Grommet, Angela B. and Lee, Lucia M. and Klajn, Rafal}, issn = {1520-4898}, journal = {Accounts of Chemical Research}, keywords = {General Medicine, General Chemistry}, number = {11}, pages = {2600--2610}, publisher = {American Chemical Society}, title = {{Molecular photoswitching in confined spaces}}, doi = {10.1021/acs.accounts.0c00434}, volume = {53}, year = {2020}, } @article{13362, abstract = {Aggregation of organic molecules can drastically affect their physicochemical properties. For instance, the optical properties of BODIPY dyes are inherently related to the degree of aggregation and the mutual orientation of BODIPY units within these aggregates. Whereas the noncovalent aggregation of various BODIPY dyes has been studied in diverse media, the ill-defined nature of these aggregates has made it difficult to elucidate the structure–property relationships. Here, we studied the encapsulation of three structurally simple BODIPY derivatives within the hydrophobic cavity of a water-soluble, flexible PdII6L4 coordination cage. The cavity size allowed for the selective encapsulation of two dye molecules, irrespective of the substitution pattern on the BODIPY core. Working with a model, a pentamethyl-substituted derivative, we found that the mutual orientation of two BODIPY units in the cage’s cavity was remarkably similar to that in the crystalline state of the free dye, allowing us to isolate and characterize the smallest possible noncovalent H-type BODIPY aggregate, namely, an H-dimer. Interestingly, a CF3-substituted BODIPY, known for forming J-type aggregates, was also encapsulated as an H-dimer. Taking advantage of the dynamic nature of encapsulation, we developed a system in which reversible switching between H- and J-aggregates can be induced for multiple cycles simply by addition and subsequent destruction of the cage. We expect that the ability to rapidly and reversibly manipulate the optical properties of supramolecular inclusion complexes in aqueous media will open up avenues for developing detection systems that operate within biological environments.}, author = {Gemen, Julius and Ahrens, Johannes and Shimon, Linda J. W. and Klajn, Rafal}, issn = {1520-5126}, journal = {Journal of the American Chemical Society}, keywords = {Colloid and Surface Chemistry, Biochemistry, General Chemistry, Catalysis}, number = {41}, pages = {17721--17729}, publisher = {American Chemical Society}, title = {{Modulating the optical properties of BODIPY dyes by noncovalent dimerization within a flexible coordination cage}}, doi = {10.1021/jacs.0c08589}, volume = {142}, year = {2020}, } @article{13363, abstract = {Temporal activation of biological processes by visible light and subsequent return to an inactive state in the absence of light is an essential characteristic of photoreceptor cells. Inspired by these phenomena, light-responsive materials are very attractive due to the high spatiotemporal control of light irradiation, with light being able to precisely orchestrate processes repeatedly over many cycles. Herein, it is reported that light-driven proton transfer triggered by a merocyanine-based photoacid can be used to modulate the permeability of pH-responsive polymersomes through cyclic, temporally controlled protonation and deprotonation of the polymersome membrane. The membranes can undergo repeated light-driven swelling–contraction cycles without losing functional effectiveness. When applied to enzyme loaded-nanoreactors, this membrane responsiveness is used for the reversible control of enzymatic reactions. This combination of the merocyanine-based photoacid and pH-switchable nanoreactors results in rapidly responding and versatile supramolecular systems successfully used to switch enzymatic reactions ON and OFF on demand.}, author = {Moreno, Silvia and Sharan, Priyanka and Engelke, Johanna and Gumz, Hannes and Boye, Susanne and Oertel, Ulrich and Wang, Peng and Banerjee, Susanta and Klajn, Rafal and Voit, Brigitte and Lederer, Albena and Appelhans, Dietmar}, issn = {1613-6829}, journal = {Small}, keywords = {Biomaterials, Biotechnology, General Materials Science, General Chemistry}, number = {37}, publisher = {Wiley}, title = {{Light‐driven proton transfer for cyclic and temporal switching of enzymatic nanoreactors}}, doi = {10.1002/smll.202002135}, volume = {16}, year = {2020}, } @article{13364, abstract = {Photochromic molecules undergo reversible isomerization upon irradiation with light at different wavelengths, a process that can alter their physical and chemical properties. For instance, dihydropyrene (DHP) is a deep-colored compound that isomerizes to light-brown cyclophanediene (CPD) upon irradiation with visible light. CPD can then isomerize back to DHP upon irradiation with UV light or thermally in the dark. Conversion between DHP and CPD is thought to proceed via a biradical intermediate; bimolecular events involving this unstable intermediate thus result in rapid decomposition and poor cycling performance. Here, we show that the reversible isomerization of DHP can be stabilized upon confinement within a PdII6L4 coordination cage. By protecting this reactive intermediate using the cage, each isomerization reaction proceeds to higher yield, which significantly decreases the fatigue experienced by the system upon repeated photocycling. Although molecular confinement is known to help stabilize reactive species, this effect is not typically employed to protect reactive intermediates and thus improve reaction yields. We envisage that performing reactions under confinement will not only improve the cyclic performance of photochromic molecules, but may also increase the amount of product obtainable from traditionally low-yielding organic reactions.}, author = {Canton, Martina and Grommet, Angela B. and Pesce, Luca and Gemen, Julius and Li, Shiming and Diskin-Posner, Yael and Credi, Alberto and Pavan, Giovanni M. and Andréasson, Joakim and Klajn, Rafal}, issn = {1520-5126}, journal = {Journal of the American Chemical Society}, keywords = {Colloid and Surface Chemistry, Biochemistry, General Chemistry, Catalysis}, number = {34}, pages = {14557--14565}, publisher = {American Chemical Society}, title = {{Improving fatigue resistance of dihydropyrene by encapsulation within a coordination cage}}, doi = {10.1021/jacs.0c06146}, volume = {142}, year = {2020}, }