Jun 2024 • Biomedical Spectroscopy, Microscopy, and Imaging III, PC130060X, 2024
Vladimir Katanaev, Dror Fixler, Martin Lopez Garcia, Maria Godinho, Nicolina Pop, Jelena Radovanovic, Maurizio Dabbicco, George A Mousdis, Ahu Gumrah Parry, Panagiotis E Keivanidis, Dragan Indjin, Ana Almeida, Paweł Wityk, Malgosia Szczerska
Numerous biological surfaces exhibit intricate micro- and nano-structures, which fulfill various functions such as anti-reflective properties, structural coloration, anti-fouling capabilities, and pro- or anti-adhesive characteristics. These features have inspired a plethora of industrial applications. In recent years, there has been a significant surge in research in this domain, largely attributable to the growing interdisciplinary nature of the approaches applied to the investigation of structured biosurfaces. The convergence of classical zoology and botany with advances in genetics and molecular biology is noteworthy, as biologists increasingly collaborate with nanotechnologists, materials scientists, and engineers. This collaborative effort contributes significantly to expanding the horizons of research on micro- and nano-structured biological surfaces, fostering biomimetic and bioengineering applications in various industries …
Show moreJun 2024 • Physical Review Research
Santiago Hernández-Gómez, Stefano Gherardini, Alessio Belenchia, Matteo Lostaglio, Amikam Levy, Nicole Fabbri
Quantum correlation functions are a natural way to encode multitime information, as they are ubiquitous in analysis from fluctuation theorems to information scrambling. Correlation functions can be identified with quasiprobabilities associated to quantum processes. In this work we show how these can be measured via error-cancellation techniques, using projective measurements only and no ancillae. The scheme is implemented in a nitrogen-vacancy center in diamond undergoing a unitary quantum work protocol. We reconstruct quantum-mechanical time correlations encoded in the Margenau-Hills quasiprobabilities by observing work extraction peaks five times those of sequential projective energy measurement schemes and in violation of newly derived stochastic bounds. We interpret the phenomenon via anomalous energy exchanges due to the underlying negativity of the quasiprobability distribution.
Show moreJun 2024 • Frontiers in Molecular Neuroscience 17, 1371738, 2024
Allegra Coppini, Alessandro Falconieri, Oz Mualem, Syeda Rubaiya Nasrin, Marine Roudon, Gadiel Saper, Henry Hess, Akira Kakugo, Vittoria Raffa, Orit Shefi
Biological structures have evolved to very efficiently generate, transmit, and withstand mechanical forces. These biological examples have inspired mechanical engineers for centuries and led to the development of critical insights and concepts. However, progress in mechanical engineering also raises new questions about biological structures. The past decades have seen the increasing study of failure of engineered structures due to repetitive loading, and its origin in processes such as materials fatigue. Repetitive loading is also experienced by some neurons, for example in the peripheral nervous system. This perspective, after briefly introducing the engineering concept of mechanical fatigue, aims to discuss the potential effects based on our knowledge of cellular responses to mechanical stresses. A particular focus of our discussion are the effects of mechanical stress on axons and their cytoskeletal structures. Furthermore, we highlight the difficulty of imaging these structures and the promise of new microscopy techniques. The identification of repair mechanisms and paradigms underlying long-term stability is an exciting and emerging topic in biology as well as a potential source of inspiration for engineers.
Show moreJun 2024 • Frontiers in Molecular Neuroscience 17, 1371738, 2024
Allegra Coppini, Alessandro Falconieri, Oz Mualem, Syeda Rubaiya Nasrin, Marine Roudon, Gadiel Saper, Henry Hess, Akira Kakugo, Vittoria Raffa, Orit Shefi
Biological structures have evolved to very efficiently generate, transmit, and withstand mechanical forces. These biological examples have inspired mechanical engineers for centuries and led to the development of critical insights and concepts. However, progress in mechanical engineering also raises new questions about biological structures. The past decades have seen the increasing study of failure of engineered structures due to repetitive loading, and its origin in processes such as materials fatigue. Repetitive loading is also experienced by some neurons, for example in the peripheral nervous system. This perspective, after briefly introducing the engineering concept of mechanical fatigue, aims to discuss the potential effects based on our knowledge of cellular responses to mechanical stresses. A particular focus of our discussion are the effects of mechanical stress on axons and their cytoskeletal structures. Furthermore, we highlight the difficulty of imaging these structures and the promise of new microscopy techniques. The identification of repair mechanisms and paradigms underlying long-term stability is an exciting and emerging topic in biology as well as a potential source of inspiration for engineers.
Show moreJun 2024 • Physical Review B
Dominik Szombathy, Miklós Antal Werner, Cătălin Paşcu Moca, Örs Legeza, Assaf Hamo, Shahal Ilani, Gergely Zaránd
The collective tunneling of a Wigner necklace—a crystal-like state of a small number of strongly interacting electrons confined to a suspended nanotube and subject to a double-well potential—is theoretically analyzed and compared with experiments in Shapir et al. [Science 364, 870 (2019)0036-807510.1126/science.aat0905]. Density matrix renormalization group computations, exact diagonalization, and instanton theory provide a consistent description of this very strongly interacting system, and show good agreement with experiments. Experimentally extracted and theoretically computed tunneling amplitudes exhibit a scaling collapse. Collective quantum fluctuations renormalize the tunneling, and substantially enhance it as the number of electrons increases.
Show moreJun 2024 • Physical Review E
Ruoyu Yin, Qingyuan Wang, Eli Barkai
Repeatedly monitored quantum walks with a rate yield discrete-time trajectories which are inherently random. With these paths the first-hitting time with sharp restart is studied. We find an instability in the optimal mean hitting time, which is not found in the corresponding classical random-walk process. This instability implies that a small change in parameters can lead to a rather large change of the optimal restart time. We show that the optimal restart time versus , as a control parameter, exhibits sets of staircases and plunges. The plunges, are due to the mentioned instability, which in turn is related to the quantum oscillations of the first-hitting time probability, in the absence of restarts. Furthermore, we prove that there are only two patterns of staircase structures, dependent on the parity of the distance between the target and the source in units of lattice constant. The global minimum of the hitting time is controlled not only …
Show moreJun 2024 • Photonics
Yuval Tamir, Sara Meir, Hamootal Duadi, Moti Fridman
Time lenses can measure ultrafast signals but are based on single-mode fibers (SMFs). To develop multimode time lenses that are based on a four-wave mixing process, we must have full control of the nonlinear interaction between the modes. Specifically, we need to generate an idler from each mode without any cross-talk between the modes. Here, as a first step toward a multimode time lens, we study how stable a short pulse is traveling in a multimode fiber, and how pulses at different modes interact with each other. We utilize a single-mode-based time lens to measure the dynamics of these pulses in the time and spectral domains. We found that there is cross-talk between the modes and that the pulses are not stable and excite other modes, rather than staying in the same modal order. These findings indicate that developing a multimode time-lens may be more challenging than expected.
Show moreJun 2024 • Metamaterials XIV, PC129901G, 2024
Sukanta Nandi, Shany Cohen, Danveer Singh, Michal Poplinger, Pilkhaz Nanikashvili, Doron Naveh, Tomer Lewi
Optical properties of chalcogenide topological insulators (TIs), namely, Bi2Se3 (BS) and Bi2Te3 (BT) were studied across the NIR to MIR spectral ranges. In this spectral range, the experimentally measured optical constants revealed an extremely high permittivity values amounting to refractive indices as high as n≈11 and n≈6.4, for BT and BS respectively. These ultra-high index values were then utilized for demonstrating ultracompact, deep-subwavelength nanostructures (NSs), with unit cell sizes down to ~λ/10. Finally, using scattering-type Scanning Near-field Optical Microscopy (s-SNOM), local variations in the optical constants of these nanostructured TIs were studied. Nanoscale phase mapping on a BS NS revealed the role of the imaginary component of the refractive index in the observed phase shifts, varying from as low as ~0.37π to a maximum of ~2π radians across a resonance. This work thus highlights …
Show moreJun 2024 • Micromachines
Avraham Kenigsberg, Shany Shperling, Ornit Nagler-Avramovitz, Heli Peleg-Levy, Silvia Piperno, Alon Skaat, Ari Leshno, Hagay Shpaisman, Noa Kapelushnik
Certain ocular conditions result from the non-physiological presence of intraocular particles, leading to visual impairment and potential long-term damage. This happens when the normally clear aqueous humor becomes less transparent, thus blocking the visual axis and by intraocular pressure elevation due to blockage of the trabecular meshwork, as seen in secondary open-angle glaucoma (SOAG). Some of these “particle-related pathologies” acquire ocular conditions like pigment dispersion syndrome, pseodoexfoliation and uveitis. Others are trauma-related, such as blood cell accumulation in hyphema. While medical and surgical treatments exist for SOAG, there is a notable absence of effective preventive measures. Consequently, the prevailing clinical approach predominantly adopts a “wait and see” strategy, wherein the focus lies on managing secondary complications and offers no treatment options for particulate matter disposal. We developed a new technique utilizing standing acoustic waves to trap and direct intraocular particles. By employing acoustic trapping at nodal regions and controlled movement of the acoustic transducer, we successfully directed these particles to specific locations within the angle. Here, we demonstrate control and movement of polystyrene (PS) particles to specific locations within an in vitro eye model, as well as blood cells in porcine eyes (ex vivo). The removal of particles from certain areas can facilitate the outflow of aqueous humor (AH) and help maintain optimal intraocular pressure (IOP) levels, resulting in a non-invasive tool for preventing secondary glaucoma. Furthermore, by controlling the location of …
Show moreJun 2024 • Quantum 2.0, QW3A. 42, 2024
Yoel Olivier, Dan Cohen, Leonid Vidro, Hagai Eisenberg, Matan Slook, Mirit Hen, Avi Zadok
We characterize the spectral response of a silicon chip integrated non-perfect directional coupler by measuring the biphoton joint spectrum at the Hong-Ou-Mandel dip and show the resulting spectral coupling dependency.
Show moreJun 2024 • Molecular Cancer Therapeutics
Hajime Okada, Eran Sdeor, Miriam Karmon, Erez Levanon, Uri Ben-David
Aneuploidy is an abnormal chromosome composition and a general hallmark of human cancer. Aneuploidy causes detrimental cellular stresses, but cancer cells evolve to cope with these stresses. Consequently, targeting such mitigation mechanisms is a promising potential therapeutic strategy. As an abnormal dosage of gene products from altered chromosomes can cause RNA and proteotoxic stress, dosage compensation (DC) of imbalanced gene products was reported to mitigate these stresses in aneuploid cells. However, the mechanisms that regulate DC remain elusive. To address these mechanisms, we focused on the role(s) of stress granules (SGs) and RNA binding proteins (RBPs) in aneuploid cancer cells. Our recent study revealed that aneuploid cancer cells preferentially depend on RNA and protein metabolism, and need to attenuate translation in order to cope with proteotoxic stress (Ippolito & …
Show moreJun 2024 • Specialty Optical Fibres VIII, PC130010C, 2024
Avi Zadok
A new concept for the sensing of media outside the cladding boundary of standard unmodified fibers will be presented. Light in the single optical mode is used to stimulate mechanical modes of the entire cladding cross-section. The boundary conditions for the oscillations of the mechanical modes are modified by surrounding substances: the outward dissipation of mechanical waves manifests in faster decay rates. The process is monitored through photoelastic scattering of additional optical probe waves. Point-measurements, spatially distributed analysis, and monitoring of coating layers will be presented.
Show moreJun 2024 • arXiv preprint arXiv:2406.16202
Rain Lenny, Dana Ben Porath, Eliahu Cohen
Despite their importance, there is an on-going challenge characterizing multipartite quantum correlations. The Svetlichny and Mermin-Klyshko (MK) inequalities present constraints on correlations in multipartite systems, a violation of which allows to classify the correlations by using the non-separability property. In this work we present refined Tsirelson (quantum) bounds on these inequalities, derived from inequalities stemming from a fundamental constraint, tightly akin to quantum uncertainty. Unlike the original, known inequalities, our bounds do not consist of a single constant point but rather depend on correlations in specific subsystems (being local correlations for our bounds on the Svetlichny operators and bipartite correlations for our bounds on the MK operators). We analyze concrete examples in which our bounds are strictly tighter than the known bounds.
Show moreJun 2024 • Biomedical Spectroscopy, Microscopy, and Imaging III 13006, 130060T, 2024
Michal Katan, Hamootal Duadi, Dror Fixler
Traditional methods for measuring blood oxygen use multiple wavelengths, which produces an In the biomedical field, the reemitted light intensity measured from the tissue depends on both scattering and absorption. In order to separate these variables, we use a physical phenomenon discovered in our lab, called the iso-path length (IPL) point. The IPL point is a specific angle around a cylindrical media, where the light intensity is not affected by the scattering and can serve for self-calibration. For a practical use of this concept, we designed an optic biosensor for measuring physiological parameters such as heart rate, oxygen saturation and respiratory rate, in both ordinary and extreme conditions in a hypoxic chamber.
Show moreJun 2024 • Biophysical Reports
Melanie Hirsch, Lukas Hofmann, Idan Yakobov, Shirin Kahremany, Hila Sameach, Yulia Shenberger, Lada Gevorkyan-Airapetov, Sharon Ruthstein
Electron Paramagnetic Resonance (EPR) is a powerful tool for elucidating both static and dynamic conformational alterations in macromolecules. However, to effectively utilize EPR for such investigations, the presence of paramagnetic enters, known as spin-labels, is required. The process of spin-labeling, particularly for nucleotides, typically demands intricate organic synthesis techniques. In this study, we introduce a unique addition-elimination reaction method with a simple spin-labeling process, facilitating the monitoring of structural changes within nucleotide sequence. Our investigation focuses on three distinct labeling positions with a DNA sequence, allowing the measurement of distance between two spin-labels. The experimental mean distances obtained agreed with the calculated distances, underscoring the efficacy of this straightforward spin-labelling approach in studying complex biological processes …
Show moreJun 2024 • Metamaterials XIV, PC129901G, 2024
Sukanta Nandi, Shany Cohen, Danveer Singh, Michal Poplinger, Pilkhaz Nanikashvili, Doron Naveh, Tomer Lewi
Optical properties of chalcogenide topological insulators (TIs), namely, Bi2Se3 (BS) and Bi2Te3 (BT) were studied across the NIR to MIR spectral ranges. In this spectral range, the experimentally measured optical constants revealed an extremely high permittivity values amounting to refractive indices as high as n≈11 and n≈6.4, for BT and BS respectively. These ultra-high index values were then utilized for demonstrating ultracompact, deep-subwavelength nanostructures (NSs), with unit cell sizes down to ~λ/10. Finally, using scattering-type Scanning Near-field Optical Microscopy (s-SNOM), local variations in the optical constants of these nanostructured TIs were studied. Nanoscale phase mapping on a BS NS revealed the role of the imaginary component of the refractive index in the observed phase shifts, varying from as low as ~0.37π to a maximum of ~2π radians across a resonance. This work thus highlights …
Show moreJun 2024 • Annals of the Rheumatic Diseases 83, 50-51, 2024
K Dürholz, M Linnerbauer, E Schmid, H Danzer, V Azizov, S Lucas, L Lößlein, L Amend, H Bootz-Maoz, H Romano, Y Reich, A Gessner, D Mauro, F Beyer, R Beckervordersandforth, W Xiang, A Haghikia, C Akdis, T Baeuerle, K Sarter, T Strowig, F Ciccia, N Yissachar, G Schett, V Rothhammer, MM Zaiss
Background Chronic peripheral inflammation is well-documented for its ability to alter the activation of the central nervous system (CNS) in diseases such as rheumatoid arthritis (RA) [1]. Furthermore, the CNS is able to regulate inflammatory processes in the periphery [2]. However, the environmental factors facilitating CNS-mediated suppression of peripheral inflammation in RA remain less explored. The intestinal microbiota produces immunomodulatory metabolites, including short-chain fatty acids (SCFA) [3], and neuroactive substances like histamine, which exhibit local and systemic effects [4]. While histamine is commonly associated with allergic reactions, it also possesses immunoregulatory function [5].Objectives Our study aimed to elucidate the impact of gut microbiota-derived histamine on peripheral inflammation.Methods Mice with collagen-induced arthritis (CIA) were orally treated with histamine-producing …
Show moreJun 2024 • Biomedical Spectroscopy, Microscopy, and Imaging III 13006, 163-166, 2024
Sammy Apsel, Vika Tarle, Michal Yemini, Zeev Zalevsky, Nisan Ozana
In this paper, an innovative approach for detecting and analyzing speckle pattern signals is demonstrated, based on dynamic speckle analysis using a low-cost and low-framerate rolling shutter (RS) CMOS image sensor. The row scanning mechanism of a rolling shutter camera samples dynamic speckle patterns at a higher rate than typical Global Shutter (GS) cameras. In this research we demonstrate the detection and analysis of vibration signals that arise from an acoustic signal. We will illustrate the process of reconstructing a voice signal by analyzing a vibrating speckle pattern, with a primary focus on detecting and audibly capturing lung sounds.
Show moreJun 2024 • Quantum Technologies 2024, PC129930R, 2024
Francesco Atzori, Salvatore Virzì, Enrico Rebufello, Alessio Avella, Fabrizio Piacentini, Rudi Lussana, Iris Cusini, Francesco Madonini, Federica Villa, Marco Gramegna, Eliahu Cohen, Ivo Pietro Degiovanni, Marco Genovese
Bell tests serve as a fundamental tool in both quantum technologies and quantum foundations investigation. The traditional Bell test framework involves the use of projective measurements, which, because of the wavefunction collapse and the Heisenberg uncertainty principle, do not allow for the full estimation of the Bell parameter from each entangled pair. In this work, we propose a novel weak-measurement-based scheme enabling the complete estimation of the entire Bell parameter from each entangled pair. Moreover, this approach prevents the collapse of the quantum state wavefunction, thereby preserving the entanglement within it. Our results, showing a 6 standard deviations violation of the Bell inequality tested, are obtained while leaving the entanglement within the photon pair almost unaltered after the weak measurement scheme (as demonstrated by our quantum tomographic reconstructions), allowing …
Show moreJun 2024 • Frontiers in Molecular Neuroscience 17, 1371738, 2024
Henry Hess, Allegra Coppini, Alessandro Falconieri, Oz Mualem, Syeda Rubaiya Nasrin, Marine Roudon, Gadiel Saper, Akira Kakugo, Vittoria Raffa, Orit Shefi
Biological structures have evolved to very efficiently generate, transmit, and withstand mechanical forces. These biological examples have inspired mechanical engineers for centuries and led to the development of critical insights and concepts. However, progress in mechanical engineering also raises new questions about biological structures. The past decades have seen the increasing study of failure of engineered structures due to repetitive loading, and its origin in processes such as materials fatigue. Repetitive loading is also experienced by some neurons, for example in the peripheral nervous system. This perspective, after briefly introducing the engineering concept of mechanical fatigue, aims to discuss the potential effects based on our knowledge of cellular responses to mechanical stresses. A particular focus of our discussion are the effects of mechanical stress on axons and their cytoskeletal structures. Furthermore, we highlight the difficulty of imaging these structures and the promise of new microscopy techniques. The identification of repair mechanisms and paradigms underlying long-term stability is an exciting and emerging topic in biology as well as a potential source of inspiration for engineers.
Show moreJun 2024 • Genes & Immunity
Eric Engelbrecht, Oscar L Rodriguez, Kaitlyn Shields, Steven Schultze, David Tieri, Uddalok Jana, Gur Yaari, William D Lees, Melissa L Smith, Corey T Watson
Immunoglobulins (IGs), critical components of the human immune system, are composed of heavy and light protein chains encoded at three genomic loci. The IG Kappa (IGK) chain locus consists of two large, inverted segmental duplications. The complexity of the IG loci has hindered use of standard high-throughput methods for characterizing genetic variation within these regions. To overcome these limitations, we use long-read sequencing to create haplotype-resolved IGK assemblies in an ancestrally diverse cohort (n = 36), representing the first comprehensive description of IGK haplotype variation. We identify extensive locus polymorphism, including novel single nucleotide variants (SNVs) and novel structural variants harboring functional IGKV genes. Among 47 functional IGKV genes, we identify 145 alleles, 67 of which were not previously curated. We report inter-population differences in allele frequencies …
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