bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phonon-driven intra-exciton Rabi oscillations in CsPbBr3 halide perovskites
Authors: Nguyen Xuan Trung , Winte Katrin , Timmer Daniel , Rakita Yevgeny , Ceratti Davide Raffaele , Aharon Sigalit , Ramzan Muhammad Sufyan , Cocchi Caterina , Lorke Michael , Jahnke Frank , Cahen David , Lienau Christoph , De Sio Antonietta 
Published: February 2023

AbstractCoupling electromagnetic radiation with matter, e.g., by resonant light fields in external optical cavities, is highly promising for tailoring the optoelectronic properties of functional materials on the nanoscale. Here, we demonstrate that even internal fields induced by coherent lattice motions can be used to control the transient excitonic optical response in CsPbBr3 halide perovskite crystals. Upon resonant photoexcitation, two-dimensional electronic spectroscopy reveals an excitonic peak structure oscillating persistently with a 100-fs period for up to ~2 ps which does not match the frequency of any phonon modes of the crystals. Only at later times, beyond 2 ps, two low-frequency phonons of the lead-bromide lattice dominate the dynamics. We rationalize these findings by an unusual exciton-phonon coupling inducing off-resonant 100-fs Rabi oscillations between 1s and 2p excitons driven by the low-frequency phonons. As such, prevailing models for the electron-phonon coupling in halide perovskites are insufficient to explain these results. We propose the coupling of characteristic low-frequency phonon fields to intra-excitonic transitions in halide perovskites as the key to control the anharmonic response of these materials in order to establish new routes for enhancing their optoelectronic properties.
Fundamental limits to learning closed-form mathematical models from data
Authors: Fajardo-Fontiveros Oscar , Reichardt Ignasi , De Los Ríos Harry R. , Duch Jordi , Sales-Pardo Marta , Guimerà Roger 
Published: February 2023

AbstractGiven a finite and noisy dataset generated with a closed-form mathematical model, when is it possible to learn the true generating model from the data alone? This is the question we investigate here. We show that this model-learning problem displays a transition from a low-noise phase in which the true model can be learned, to a phase in which the observation noise is too high for the true model to be learned by any method. Both in the low-noise phase and in the high-noise phase, probabilistic model selection leads to optimal generalization to unseen data. This is in contrast to standard machine learning approaches, including artificial neural networks, which in this particular problem are limited, in the low-noise phase, by their ability to interpolate. In the transition region between the learnable and unlearnable phases, generalization is hard for all approaches including probabilistic model selection.
Noncanonical amino acids as doubly bio-orthogonal handles for one-pot preparation of protein multiconjugates
Authors: Wang Yong , Zhang Jingming , Han Boyang , Tan Linzhi , Cai Wenkang , Li Yuxuan , Su Yeyu , Yu Yutong , Wang Xin , Duan Xiaojiang , Wang Haoyu , Shi Xiaomeng , Wang Jing , Yang Xing , Liu Tao 
Published: February 2023

AbstractGenetic encoding of noncanonical amino acid (ncAA) for site-specific protein modification has been widely applied for many biological and therapeutic applications. To efficiently prepare homogeneous protein multiconjugates, we design two encodable noncanonical amino acids (ncAAs), 4-(6-(3-azidopropyl)-s-tetrazin-3-yl) phenylalanine (pTAF) and 3-(6-(3-azidopropyl)-s-tetrazin-3-yl) phenylalanine (mTAF), containing mutually orthogonal and bioorthogonal azide and tetrazine reaction handles. Recombinant proteins and antibody fragments containing the TAFs can easily be functionalized in one-pot reactions with combinations of commercially available fluorophores, radioisotopes, PEGs, and drugs in a plug-and-play manner to afford protein dual conjugates to assess combinations of tumor diagnosis, image-guided surgery, and targeted therapy in mouse models. Furthermore, we demonstrate that simultaneously incorporating mTAF and a ketone-containing ncAA into one protein via two non-sense codons allows preparation of a site-specific protein triconjugate. Our results demonstrate that TAFs are doubly bio-orthogonal handles for efficient and scalable preparation of homogeneous protein multiconjugates.
Visible light-exposed lignin facilitates cellulose solubilization by lytic polysaccharide monooxygenases
Authors: Kommedal Eirik G. , Angeltveit Camilla F. , Klau Leesa J. , Ayuso-Fernández Iván , Arstad Bjørnar , Antonsen Simen G. , Stenstrøm Yngve , Ekeberg Dag , Gírio Francisco , Carvalheiro Florbela , Horn Svein J. , Aachmann Finn Lillelund , Eijsink Vincent G. H. 
Published: February 2023

AbstractLytic polysaccharide monooxygenases (LPMOs) catalyze oxidative cleavage of crystalline polysaccharides such as cellulose and are crucial for the conversion of plant biomass in Nature and in industrial applications. Sunlight promotes microbial conversion of plant litter; this effect has been attributed to photochemical degradation of lignin, a major redox-active component of secondary plant cell walls that limits enzyme access to the cell wall carbohydrates. Here, we show that exposing lignin to visible light facilitates cellulose solubilization by promoting formation of H2O2 that fuels LPMO catalysis. Light-driven H2O2 formation is accompanied by oxidation of ring-conjugated olefins in the lignin, while LPMO-catalyzed oxidation of phenolic hydroxyls leads to the required priming reduction of the enzyme. The discovery that light-driven abiotic reactions in Nature can fuel H2O2-dependent redox enzymes involved in deconstructing lignocellulose may offer opportunities for bioprocessing and provides an enzymatic explanation for the known effect of visible light on biomass conversion.
A thousand-genome panel retraces the global spread and adaptation of a major fungal crop pathogen
Authors: Feurtey Alice , Lorrain Cécile , McDonald Megan C. , Milgate Andrew , Solomon Peter S. , Warren Rachael , Puccetti Guido , Scalliet Gabriel , Torriani Stefano F. F. , Gout Lilian , Marcel Thierry C. , Suffert Frédéric , Alassimone Julien , Lipzen Anna , Yoshinaga Yuko , Daum Christopher , Barry Kerrie , Grigoriev Igor V. , Goodwin Stephen B. , Genissel Anne , Seidl Michael F. , Stukenbrock Eva H. , Lebrun Marc-Henri , Kema Gert H. J. , McDonald Bruce A. , Croll Daniel 
Published: February 2023

AbstractHuman activity impacts the evolutionary trajectories of many species worldwide. Global trade of agricultural goods contributes to the dispersal of pathogens reshaping their genetic makeup and providing opportunities for virulence gains. Understanding how pathogens surmount control strategies and cope with new climates is crucial to predicting the future impact of crop pathogens. Here, we address this by assembling a global thousand-genome panel of Zymoseptoria tritici, a major fungal pathogen of wheat reported in all production areas worldwide. We identify the global invasion routes and ongoing genetic exchange of the pathogen among wheat-growing regions. We find that the global expansion was accompanied by increased activity of transposable elements and weakened genomic defenses. Finally, we find significant standing variation for adaptation to new climates encountered during the global spread. Our work shows how large population genomic panels enable deep insights into the evolutionary trajectory of a major crop pathogen.
The cofactor-dependent folding mechanism of Drosophila cryptochrome revealed by single-molecule pulling experiments
Authors: Foroutannejad Sahar , Good Lydia L. , Lin Changfan , Carter Zachariah I. , Tadesse Mahlet G. , Lucius Aaron L. , Crane Brian R. , Maillard Rodrigo A. 
Published: February 2023

AbstractThe link between cofactor binding and protein activity is well-established. However, how cofactor interactions modulate folding of large proteins remains unknown. We use optical tweezers, clustering and global fitting to dissect the folding mechanism of Drosophila cryptochrome (dCRY), a 542-residue protein that binds FAD, one of the most chemically and structurally complex cofactors in nature. We show that the first dCRY parts to fold are independent of FAD, but later steps are FAD-driven as the remaining polypeptide folds around the cofactor. FAD binds to largely unfolded intermediates, yet with association kinetics above the diffusion-limit. Interestingly, not all FAD moieties are required for folding: whereas the isoalloxazine ring linked to ribitol and one phosphate is sufficient to drive complete folding, the adenosine ring with phosphates only leads to partial folding. Lastly, we propose a dCRY folding model where regions that undergo conformational transitions during signal transduction are the last to fold.
Chiral electrocatalysts eclipse water splitting metrics through spin control
Authors: Vadakkayil Aravind , Clever Caleb , Kunzler Karli N. , Tan Susheng , Bloom Brian P. , Waldeck David H. 
Published: February 2023

AbstractContinual progress in technologies that rely on water splitting are often hampered by the slow kinetics associated with the oxygen evolution reaction (OER). Here, we show that the efficiency of top-performing catalysts can be improved, beyond typical thermodynamic considerations, through control over reaction intermediate spin alignment during electrolysis. Spin alignment is achieved using the chiral induced spin selectivity (CISS) effect and the improvement in OER manifests as an increase in Faradaic efficiency, decrease in reaction overpotential, and change in the rate determining step for chiral nanocatalysts over compositionally analogous achiral nanocatalysts. These studies illustrate that a defined spatial orientation of the nanocatalysts is not necessary to exhibit spin selectivity and therefore represent a viable platform for employing the transformative role of chirality in other reaction pathways and processes.
Spintronic leaky-integrate-fire spiking neurons with self-reset and winner-takes-all for neuromorphic computing
Authors: Wang Di , Tang Ruifeng , Lin Huai , Liu Long , Xu Nuo , Sun Yan , Zhao Xuefeng , Wang Ziwei , Wang Dandan , Mai Zhihong , Zhou Yongjian , Gao Nan , Song Cheng , Zhu Lijun , Wu Tom , Liu Ming , Xing Guozhong 
Published: February 2023

AbstractNeuromorphic computing using nonvolatile memories is expected to tackle the memory wall and energy efficiency bottleneck in the von Neumann system and to mitigate the stagnation of Moore’s law. However, an ideal artificial neuron possessing bio-inspired behaviors as exemplified by the requisite leaky-integrate-fire and self-reset (LIFT) functionalities within a single device is still lacking. Here, we report a new type of spiking neuron with LIFT characteristics by manipulating the magnetic domain wall motion in a synthetic antiferromagnetic (SAF) heterostructure. We validate the mechanism of Joule heating modulated competition between the Ruderman–Kittel–Kasuya–Yosida interaction and the built-in field in the SAF device, enabling it with a firing rate up to 17 MHz and energy consumption of 486 fJ/spike. A spiking neuron circuit is implemented with a latency of 170 ps and power consumption of 90.99 μW. Moreover, the winner-takes-all is executed with a current ratio >104 between activated and inhibited neurons. We further establish a two-layer spiking neural network based on the developed spintronic LIFT neurons. The architecture achieves 88.5% accuracy on the handwritten digit database benchmark. Our studies corroborate the circuit compatibility of the spintronic neurons and their great potential in the field of intelligent devices and neuromorphic computing.
Theoretical and experimental analysis of circularly polarized luminescence spectrophotometers for artifact-free measurements using a single CCD camera
Authors: Baguenard Bruno , Bensalah-Ledoux Amina , Guy Laure , Riobé François , Maury Olivier , Guy Stéphan 
Published: February 2023

AbstractCircularly polarized luminescence (CPL) is a fast growing research field as a complementary chiroptical spectroscopy alternative to the conventional circular dichroism or in the quest of devices producing circularly polarized light for different applications. Because chiroptical signals are generally lower than 0.1%, conventional chiral spectroscopies rely on polarization time modulation requiring step-by-step wavelength scanning and a long acquisition time. High throughput controls motivated the development of CPL spectrophotometers using cameras as detectors and space polarization splitting. However, CPL measurements imposes careful precautions to minimize the numerous artifacts arising from experimental imperfections. Some previous work used complex calibration procedure to this end. Here we present a rigorous Mueller analysis of an instrument based on polarizations space splitting. We show that by using one camera and combining spatial and temporal separation through two switchable circular polarization encoding arms we can record accurate CPL spectra without the need of any calibration. The measurements robustness and their fast acquisition times are exemplified on different chiral emitters.
Mid-infrared cross-comb spectroscopy
Authors: Liu Mingchen , Gray Robert M. , Costa Luis , Markus Charles R. , Roy Arkadev , Marandi Alireza 
Published: February 2023

AbstractDual-comb spectroscopy has been proven beneficial in molecular characterization but remains challenging in the mid-infrared region due to difficulties in sources and efficient photodetection. Here we introduce cross-comb spectroscopy, in which a mid-infrared comb is upconverted via sum-frequency generation with a near-infrared comb of a shifted repetition rate and then interfered with a spectral extension of the near-infrared comb. We measure CO2absorption around 4.25 µm with a 1-µm photodetector, exhibiting a 233-cm−1instantaneous bandwidth, 28000 comb lines, a single-shot signal-to-noise ratio of 167 and a figure of merit of 2.4 × 106Hz1/2. We show that cross-comb spectroscopy can have superior signal-to-noise ratio, sensitivity, dynamic range, and detection efficiency compared to other dual-comb-based methods and mitigate the limits of the excitation background and detector saturation. This approach offers an adaptable and powerful spectroscopic method outside the well-developed near-IR region and opens new avenues to high-performance frequency-comb-based sensing with wavelength flexibility.
Classification of deep-sea cold seep bacteria by transformer combined with Raman spectroscopy
Authors: Liu Bo , Liu Kunxiang , Qi Xiaoqing , Zhang Weijia , Li Bei 
Published: February 2023

AbstractRaman spectroscopy is a rapid analysis method of biological samples without labeling and destruction. At present, the commonly used Raman spectrum classification models include CNN, RNN, etc. The transformer has not been used for Raman spectrum identification. This paper introduces a new method of transformer combined with Raman spectroscopy to identify deep-sea cold seep microorganisms at the single-cell level. We collected the Raman spectra of eight cold seep bacteria, each of which has at least 500 spectra for the training of transformer model. We compare the transformer classification model with other deep learning classification models. The experimental results show that this method can improve the accuracy of microbial classification. Our average isolation level accuracy is more than 97%.
The microstructure, mechanical and electrochemical properties of 3D printed alloys with reusing powders
Authors: Bajt Leban Mirjam , Hren Miha , Kosec Tadeja 
Published: February 2023

AbstractCoCrMo and Ti6Al4V are widely used in medical, dental and 3D printing technology, allowing the accurate fabrication of geometrically complicated structures. In order to reduce the costs of printed objects, the reuse of powder is common daily practice. When using 3D printing technology, the direct impact of elevated temperatures and the influence of the laser beam may change the properties of the powder when it is reused, thus affecting the final properties of the printed object. The main aim of the present study was to investigate the impact of reused powder on the mechanical, microstructural and electrochemical properties of 3D printed objects. 3D printed objects fabricated from virgin and reused powder of both alloys were analyzed by metallographic observation, computed tomography, XRD and electrochemical methods. The main finding of the study was that the use of reused powder (recycled 3 times) does not detrimentally affect the mechanical and corrosion integrity of 3D printed CoCr and Ti6Al4V alloys, especially for the purpose of applications in dentistry.
Design, development, in-vitro and in-vivo evaluation of polylactic acid-based multifunctional nanofibrous patches for efficient healing of diabetic wounds
Authors: Ali Isra H. , Khalil Islam A. , El-Sherbiny Ibrahim M. 
Published: February 2023

AbstractImpaired healing of diabetic ulcers is one of the major complications of diabetic patients due to high susceptibility to microbial infections, impaired lymphianogenesis, edema, and consequently impairing proper healing. This could even lead to much worse complications that include severe gangrene, trauma and finally limb amputation. Therefore, this study aims to develop a multilayered durable nanofibrous wound patch loaded with three promising drugs (phenytoin, sildenafil citrate and simvastatin) each in a separate layer to target a different wound healing phase. Polylactic acid was used for the preparation of the nanofibrous matrix of the wound patch, where each drug was incorporated in a separate layer during the preparation process. Drugs release profiles were studied over 3 weeks. Results showed that both phenytoin and simvastatin were released within 14 days while sildenafil continued till 21 days. Both physicochemical and mechanical characteristics of the patches were fully assessed as well as their biodegradability, swellability, breathability and porosity. Results showed that incorporation of drugs preserved the physicochemical and mechanical properties as well as porosity of the developed nanofibers. In addition, patches were evaluated for their biocompatibility and cell adhesion capability before being tested through in-vivo diabetic wound rat model induced by alloxan for three weeks. In vivo results showed that the patches were successful in inducing proper wound healing in diabetic rat model with overcoming the above-mentioned obstacles within 3 weeks. This was confirmed through assessing wound closure as well as from histopathological studies that showed complete healing with proper cell regeneration and arrangement without forming scars.
Apparatus for attosecond transient-absorption spectroscopy in the water-window soft-X-ray region
Authors: Zinchenko Kristina S. , Ardana-Lamas Fernando , Lanfaloni Valentina Utrio , Luu Tran Trung , Pertot Yoann , Huppert Martin , Wörner Hans Jakob 
Published: February 2023

AbstractWe present an apparatus for attosecond transient-absorption spectroscopy (ATAS) featuring soft-X-ray (SXR) supercontinua that extend beyond 450 eV. This instrument combines an attosecond table-top high-harmonic light source with mid-infrared (mid-IR) pulses, both driven by 1.7–1.9 mJ, sub-11 fs pulses centered at 1.76 $$\upmu$$
μ
m. A remarkably low timing jitter of $$\sim$$
∼
20 as is achieved through active stabilization of the pump and probe arms of the instrument. A temporal resolution of better than 400 as is demonstrated through ATAS measurements at the argon L$$_{2,3}$$

2
,
3

-edges. A spectral resolving power of 1490 is demonstrated through simultaneous absorption measurements at the sulfur L$$_{2,3}$$

2
,
3

- and carbon K-edges of OCS. Coupled with its high SXR photon flux, this instrument paves the way to attosecond time-resolved spectroscopy of organic molecules in the gas phase or in aqueous solutions, as well as thin films of advanced materials. Such measurements will advance the studies of complex systems to the electronic time scale.
Reirradiation for local recurrence of oral, pharyngeal, and laryngeal cancers: a multi-institutional study
Authors: Yamazaki Hideya , Suzuki Gen , Aibe Norihiro , Shiomi Hiroya , Oh Ryoong-jin , Yoshida Ken , Nakamura Satoaki , Konishi Koji , Ogita Mikio 
Published: February 2023

AbstractThis study aimed to examine the efficacy and toxicity of reirradiation in patients with locally recurrent oral, pharyngeal, and laryngeal cancers. We conducted a retrospective, multi-institutional analysis of 129 patients with previously irradiated cancer. The most frequent primary sites were the nasopharynx (43.4%), oral cavity (24.8%), and oropharynx (18.6%). With a median follow-up duration of 10.6 months, the median overall survival was 14.4 months and the 2-year overall survival rate was 40.6%. For each primary site, the 2-year overall survival rates were 32.1%, 34.6%, 30%, 60.8%, and 5.7% for the hypopharynx, oral cavity, larynx, nasopharynx, and oropharynx, respectively. Prognostic factors for overall survival were primary site (nasopharynx versus other sites) and gross tumor volume (GTV) (≤ 25 cm3 versus > 25 cm3). The 2-year local control rate was 41.2%. Twenty-four patients (18.6%) presented with grade ≥ 3 toxicities, including nine with hemorrhages that led to grade 5 toxicities in seven patients. All nine tumors that caused hemorrhage showed tumor encasement of the carotid ≥ 180 degrees and eight of nine tumors had larger GTV > 25 cm3. Reirradiation is a feasible treatment option for small local recurrence of oral, pharyngeal, and laryngeal cancers, with the requirement of a strict eligibility assessment for large tumors with carotid encasement.
Heterogenous effects of the Great East Japan earthquake on prosociality of people depending on their age
Authors: Sawada Yasuyuki , Ashida Toyo , Iwasaki Keiko 
Published: February 2023

AbstractThis study investigates the instability of prosociality in the real world by looking at the age-specific non-linear relationship between disaster exposure and prosocial behavior. We employed unique microdata from two communities in Japan that were hit by the Great East Japan Earthquake and Tsunami disaster in 2011. Exploiting exogenous variations in disaster exposure, we find age-specific heterogeneous effects of disaster exposure on prosocial behavior captured by the behavior of sending New Year’s cards as well as attitudinal survey questions. Among the older groups, disaster damages undermine prosociality, whereas the younger groups show reinforced prosocial behaviors. These findings can be explained consistently by combining two possible determinants of prosocial behavior: pure or impure altruism and self-enforcements in repeated interactions at workplaces. Age information can help disentangle these two elements at least partially.