bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlated insulator collapse due to quantum avalanche via in-gap ladder states
Authors: Han Jong E. , Aron Camille , Chen Xi , Mansaray Ishiaka , Han Jae-Ho , Kim Ki-Seok , Randle Michael , Bird Jonathan P. 
Published: May 2023

AbstractThe significant discrepancy observed between the predicted and experimental switching fields in correlated insulators under a DC electric field far-from-equilibrium necessitates a reevaluation of current microscopic understanding. Here we show that an electron avalanche can occur in the bulk limit of such insulators at arbitrarily small electric field by introducing a generic model of electrons coupled to an inelastic medium of phonons. The quantum avalanche arises by the generation of a ladder of in-gap states, created by a multi-phonon emission process. Hot-phonons in the avalanche trigger a premature and partial collapse of the correlated gap. The phonon spectrum dictates the existence of two-stage versus single-stage switching events which we associate with charge-density-wave and Mott resistive phase transitions, respectively. The behavior of electron and phonon temperatures, as well as the temperature dependence of the threshold fields, demonstrates how a crossover between the thermal and quantum switching scenarios emerges within a unified framework of the quantum avalanche.
De novo cholesterol biosynthesis in bacteria
Authors: Lee Alysha K. , Wei Jeremy H. , Welander Paula V. 
Published: May 2023

AbstractEukaryotes produce highly modified sterols, including cholesterol, essential to eukaryotic physiology. Although few bacterial species are known to produce sterols, de novo production of cholesterol or other complex sterols in bacteria has not been reported. Here, we show that the marine myxobacterium Enhygromyxa salina produces cholesterol and provide evidence for further downstream modifications. Through bioinformatic analysis we identify a putative cholesterol biosynthesis pathway in E. salina largely homologous to the eukaryotic pathway. However, experimental evidence indicates that complete demethylation at C-4 occurs through unique bacterial proteins, distinguishing bacterial and eukaryotic cholesterol biosynthesis. Additionally, proteins from the cyanobacterium Calothrix sp. NIES-4105 are also capable of fully demethylating sterols at the C-4 position, suggesting complex sterol biosynthesis may be found in other bacterial phyla. Our results reveal an unappreciated complexity in bacterial sterol production that rivals eukaryotes and highlight the complicated evolutionary relationship between sterol biosynthesis in the bacterial and eukaryotic domains.
Geometry design of tethered small-molecule acceptor enables highly stable and efficient polymer solar cells
Authors: Bai Yang , Zhang Ze , Zhou Qiuju , Geng Hua , Chen Qi , Kim Seoyoung , Zhang Rui , Zhang Cen , Chang Bowen , Li Shangyu , Fu Hongyuan , Xue Lingwei , Wang Haiqiao , Li Wenbin , Chen Weihua , Gao Mengyuan , Ye Long , Zhou Yuanyuan , Ouyang Yanni , Zhang Chunfeng , Gao Feng , Yang Changduk , Li Yongfang , Zhang Zhi-Guo 
Published: May 2023

AbstractWith the power conversion efficiency of binary polymer solar cells dramatically improved, the thermal stability of the small-molecule acceptors raised the main concerns on the device operating stability. Here, to address this issue, thiophene-dicarboxylate spacer tethered small-molecule acceptors are designed, and their molecular geometries are further regulated via the thiophene-core isomerism engineering, affording dimeric TDY-α with a 2, 5-substitution and TDY-β with 3, 4-substitution on the core. It shows that TDY-α processes a higher glass transition temperature, better crystallinity relative to its individual small-molecule acceptor segment and isomeric counterpart of TDY-β, and a more stable morphology with the polymer donor. As a result, the TDY-α based device delivers a higher device efficiency of 18.1%, and most important, achieves an extrapolated lifetime of about 35000 hours that retaining 80% of their initial efficiency. Our result suggests that with proper geometry design, the tethered small-molecule acceptors can achieve both high device efficiency and operating stability.
Distinct beta frequencies reflect categorical decisions
Authors: Rassi Elie , Zhang Yi , Mendoza Germán , Méndez Juan Carlos , Merchant Hugo , Haegens Saskia 
Published: May 2023

AbstractBased on prior findings of content-specific beta synchronization in working memory and decision making, we hypothesized that beta oscillations support the (re-)activation of cortical representations by mediating neural ensemble formation. We found that beta activity in monkey dorsolateral prefrontal cortex (dlPFC) and pre-supplementary motor area (preSMA) reflects the content of a stimulus in relation to the task context, regardless of its objective properties. In duration- and distance-categorization tasks, we changed the boundary between categories from one block of trials to the next. We found that two distinct beta-band frequencies were consistently associated with the two relative categories, with activity in these bands predicting the animals’ responses. We characterized beta at these frequencies as transient bursts, and showed that dlPFC and preSMA are connected via these distinct frequency channels. These results support the role of beta in forming neural ensembles, and further show that such ensembles synchronize at different beta frequencies.
Robust microscale structural superlubricity between graphite and nanostructured surface
Authors: Huang Xuanyu , Li Tengfei , Wang Jin , Xia Kai , Tan Zipei , Peng Deli , Xiang Xiaojian , Liu Bin , Ma Ming , Zheng Quanshui 
Published: May 2023

AbstractStructural superlubricity is a state of nearly zero friction and no wear between two contacted solid surfaces. However, such state has a certain probability of failure due to the edge defects of graphite flake. Here, we achieve robust structural superlubricity state between microscale graphite flakes and nanostructured silicon surfaces under ambient condition. We find that the friction is always less than 1 μN, the differential friction coefficient is on the order of 10−4, without observable wear. This is attributed to the edge warping of graphite flake on the nanostructured surface under concentrated force, which eliminate the edge interaction between the graphite flake and the substrate. This study not only challenges the traditional understanding in tribology and structural superlubricity that rougher surfaces lead to higher friction and lead to wear, thereby reducing roughness requirements, but also demonstrates that a graphite flake with a single crystal surface that does not come into edge contact with the substrate can consistently achieve robust structural superlubricity state with any non-van der Waals material in atmospheric conditions. Additionally, the study provides a general surface modification method that enables the widespread application of structural superlubricity technology in atmospheric environments.
Linear time complexity de novo long read genome assembly with GoldRush
Authors: Wong Johnathan , Coombe Lauren , Nikolić Vladimir , Zhang Emily , Nip Ka Ming , Sidhu Puneet , Warren René L. , Birol Inanç 
Published: May 2023

AbstractCurrent state-of-the-art de novo long read genome assemblers follow the Overlap-Layout-Consensus paradigm. While read-to-read overlap – its most costly step – was improved in modern long read genome assemblers, these tools still often require excessive RAM when assembling a typical human dataset. Our work departs from this paradigm, foregoing all-vs-all sequence alignments in favor of a dynamic data structure implemented in GoldRush, a de novo long read genome assembly algorithm with linear time complexity. We tested GoldRush on Oxford Nanopore Technologies long sequencing read datasets with different base error profiles sourced from three human cell lines, rice, and tomato. Here, we show that GoldRush achieves assembly scaffold NGA50 lengths of 18.3-22.2, 0.3 and 2.6 Mbp, for the genomes of human, rice, and tomato, respectively, and assembles each genome within a day, using at most 54.5 GB of random-access memory, demonstrating the scalability of our genome assembly paradigm and its implementation.
Spin-dependent reactivity and spin-flipping dynamics in oxygen atom scattering from graphite
Authors: Zhao Zibo , Wang Yingqi , Yang Ximei , Quan Jiamei , Krüger Bastian C. , Stoicescu Paula , Nieman Reed , Auerbach Daniel J. , Wodtke Alec M. , Guo Hua , Park G. Barratt 
Published: May 2023

AbstractThe formation of two-electron chemical bonds requires the alignment of spins. Hence, it is well established for gas-phase reactions that changing a molecule’s electronic spin state can dramatically alter its reactivity. For reactions occurring at surfaces, which are of great interest during, among other processes, heterogeneous catalysis, there is an absence of definitive state-to-state experiments capable of observing spin conservation and therefore the role of electronic spin in surface chemistry remains controversial. Here we use an incoming/outgoing correlation ion imaging technique to perform scattering experiments for O(3P) and O(1D) atoms colliding with a graphite surface, in which the initial spin-state distribution is controlled and the final spin states determined. We demonstrate that O(1D) is more reactive with graphite than O(3P). We also identify electronically nonadiabatic pathways whereby incident O(1D) is quenched to O(3P), which departs from the surface. With the help of molecular dynamics simulations carried out on high-dimensional machine-learning-assisted first-principles potential energy surfaces, we obtain a mechanistic understanding for this system: spin-forbidden transitions do occur, but with low probabilities.
In vitro selection of macrocyclic peptide inhibitors containing cyclic γ2,4-amino acids targeting the SARS-CoV-2 main protease
Authors: Miura Takashi , Malla Tika R. , Owen C. David , Tumber Anthony , Brewitz Lennart , McDonough Michael A. , Salah Eidarus , Terasaka Naohiro , Katoh Takayuki , Lukacik Petra , Strain-Damerell Claire , Mikolajek Halina , Walsh Martin A. , Kawamura Akane , Schofield Christopher J. , Suga Hiroaki 
Published: May 2023

Abstractγ-Amino acids can play important roles in the biological activities of natural products; however, the ribosomal incorporation of γ-amino acids into peptides is challenging. Here we report how a selection campaign employing a non-canonical peptide library containing cyclic γ2,4-amino acids resulted in the discovery of very potent inhibitors of the SARS-CoV-2 main protease (Mpro). Two kinds of cyclic γ2,4-amino acids, cis-3-aminocyclobutane carboxylic acid (γ1) and (1R,3S)-3-aminocyclopentane carboxylic acid (γ2), were ribosomally introduced into a library of thioether-macrocyclic peptides. One resultant potent Mpro inhibitor (half-maximal inhibitory concentration = 50 nM), GM4, comprising 13 residues with γ1 at the fourth position, manifests a 5.2 nM dissociation constant. An Mpro:GM4 complex crystal structure reveals the intact inhibitor spans the substrate binding cleft. The γ1 interacts with the S1′ catalytic subsite and contributes to a 12-fold increase in proteolytic stability compared to its alanine-substituted variant. Knowledge of interactions between GM4 and Mpro enabled production of a variant with a 5-fold increase in potency.
The effect of the preferred hand on drawing movement
Authors: Zarandi Zinat , Adolfo Stucchi Natale , Fadiga Luciano , Pozzo Thierry 
Published: May 2023

AbstractThe observation that different effectors can execute the same movement suggests functional equivalences driven by limb independent representation of action in the central nervous system. A common invariant motor behavior is the speed and curvature coupling (the 1/3 power law), a low dimensional (abstract) descriptor of movement which is resilient to different sensorimotor contexts. Our purpose is to verify the consistency of such motor equivalence during a drawing task, by testing the effect of manual dominance and movement speed on motor performance. We hypothesize that abstract kinematic variables are not the most resistant to speed or limb effector changes. The results show specific effects of speed and hand side on the drawing task. Movement duration, speed-curvature covariation, and maximum velocity were not significantly affected by hand side, while geometrical features were strongly speed and limb dependent. However, intra-trial analysis performed over the successive drawing movements reveals a significant hand side effect on the variability of movement vigor and velocity-curvature relationship (the 1/3 PL). The identified effects of speed and hand dominance on the kinematic parameters suggest different neural strategies, in a pattern that does not go from the most abstract to the least abstract component, as proposed by the traditional hierarchical organization of the motor plan.
A state-of-the-art methodology for high-throughput in silico vaccine discovery against protozoan parasites and exemplified with discovered candidates for Toxoplasma gondii
Authors: Goodswen Stephen J. , Kennedy Paul J. , Ellis John T. 
Published: May 2023

AbstractVaccine discovery against eukaryotic parasites is not trivial as highlighted by the limited number of known vaccines compared to the number of protozoal diseases that need one. Only three of 17 priority diseases have commercial vaccines. Live and attenuated vaccines have proved to be more effective than subunit vaccines but adversely pose more unacceptable risks. One promising approach for subunit vaccines is in silico vaccine discovery, which predicts protein vaccine candidates given thousands of target organism protein sequences. This approach, nonetheless, is an overarching concept with no standardised guidebook on implementation. No known subunit vaccines against protozoan parasites exist as a result of this approach, and consequently none to emulate. The study goal was to combine current in silico discovery knowledge specific to protozoan parasites and develop a workflow representing a state-of-the-art approach. This approach reflectively integrates a parasite’s biology, a host's immune system defences, and importantly, bioinformatics programs needed to predict vaccine candidates. To demonstrate the workflow effectiveness, every Toxoplasma gondii protein was ranked in its capacity to provide long-term protective immunity. Although testing in animal models is required to validate these predictions, most of the top ranked candidates are supported by publications reinforcing our confidence in the approach.
Enhanced performance of nanocomposite membrane developed on sulfonated poly (1, 4-phenylene ether-ether-sulfone) with zeolite imidazole frameworks for fuel cell application
Authors: Soleimani Bita , Asl Ali Haghighi , Khoshandam Behnam , Hooshyari Khadijeh 
Published: May 2023

AbstractProton exchange membrane fuel cells (PEMFC) have received a lot of interest and use metal–organic frameworks (MOF)/polymer nanocomposite membranes. Zeolite imidazole framework-90 (ZIF-90) was employed as an addition in the sulfonated poly (1, 4-phenylene ether-ether-sulfone) (SPEES) matrix in order to investigate the proton conductivity in a novel nanocomposite membrane made of SPEES/ ZIF. The high porosity, free surface, and presence of the aldehyde group in the ZIF-90 nanostructure have a substantial impact on enhancing the mechanical, chemical, thermal, and proton conductivity capabilities of the SPEES/ZIF-90 nanocomposite membranes. The results indicate that the utilization of SPEES/ZIF-90 nanocomposite membranes with 3wt% ZIF-90 resulted in enhanced proton conductivity of up to 160 mS/cm at 90 °C and 98% relative humidity (RH). This is a significant improvement compared to the SPEES membrane which exhibited a proton conductivity of 55 mS/cm under the same conditions, indicating a 1.9-fold increase in performance. Furthermore, the SPEES/ZIF-90/3 membrane exhibited a remarkable 79% improvement in maximum power density, achieving a value of 0.52 W/cm2 at 0.5 V and 98% RH, which is 79% higher than that of the pristine SPEES membrane.
Parasympathetic autonomic dysfunction is more often evidenced than sympathetic autonomic dysfunction in fluctuating and polymorphic symptoms of "long-COVID" patients
Authors: Zanin Adrien , Amah Guy , Chakroun Sahar , Testard Pauline , Faucher Alice , Le Thi Yen Vy , Slama Dorsaf , Le Baut Valérie , Lozeron Pierre , Salmon Dominique , Kubis Nathalie 
Published: May 2023

AbstractSeveral disabling symptoms potentially related to dysautonomia have been reported in “long-COVID” patients. Unfortunately, these symptoms are often nonspecific, and autonomic nervous system explorations are rarely performed in these patients. This study aimed to evaluate prospectively a cohort of long-COVID patients presenting severe disabling and non-relapsing symptoms of potential dysautonomia and to identify sensitive tests. Autonomic function was assessed by clinical examination, the Schirmer test; sudomotor evaluation, orthostatic blood pressure (BP) variation, 24-h ambulatory BP monitoring for sympathetic evaluation, and heart rate variation during orthostatism, deep breathing and Valsalva maneuvers for parasympathetic evaluation. Test results were considered abnormal if they reached the lower thresholds defined in publications and in our department. We also compared mean values for autonomic function tests between patients and age-matched controls. Sixteen patients (median age 37 years [31–43 years], 15 women) were included in this study and referred 14.5 months (median) [12.0–16.5 months] after initial infection. Nine had at least one positive SARS-CoV-2 RT-PCR or serology result. Symptoms after SARS-CoV-2 infection were severe, fluctuating and disabling with effort intolerance. Six patients (37.5%) had one or several abnormal test results, affecting the parasympathetic cardiac function in five of them (31%). Mean Valsalva score was significantly lower in patients than in controls. In this cohort of severely disabled long-COVID patients, 37.5% of them had at least one abnormal test result showing a possible contribution of dysautonomia to these nonspecific symptoms. Interestingly, mean values of the Valsalva test were significantly lower in patients than in control subjects, suggesting that normal values thresholds might not be appropriate in this population.
Impact of different ventilation conditions on tobacco smoke-associated particulate matter emissions in a car cabin using the TAPaC platform
Authors: Pitten Lukas , Brüggmann Dörthe , Dröge Janis , Braun Markus , Groneberg David A. 
Published: May 2023

AbstractDespite antagonizing attempts from the tobacco industry, passive inhalation of tobacco smoke is known to be cancerogenic and toxic to human health for decades. Nonetheless, millions of non-smoking adults and children are still victims of second-hand smoke. Accumulation of particulate matter (PM) in confined spaces such as the car are particularly harmful due to high concentrations. We here aimed to analyze the specific effects of ventilation conditions in the setting of a car. By the use of the measuring platform TAPaC (tobacco-associated particulate matter emissions inside a car cabin), 3R4F reference cigarettes, Marlboro red, and Marlboro gold were smoked in a car interior with a volume of 3.709 m3. Seven different ventilation conditions (C1–C7) were analyzed. Under C1, all windows were closed. Under C2–C7, the car ventilation was turned on power level 2/4 with the air directed towards the windshield. Only the passenger side window was opened, where an outer placed fan could create an airstream speed of 15.9–17.4 km/h at one meter distance to simulate a driving car. C2: Window 10 cm opened. C3: Window 10 cm opened with the fan turned on. C4: Window half-opened. C5: Window half-opened with the fan turned on. C6: Window fully opened. C7: Window fully opened with the fan turned on. Cigarettes were remotely smoked by an automatic environmental tobacco smoke emitter and a cigarette smoking device. Depending on the ventilation condition the cigarettes emitted different mean PM concentrations after 10 min under condition C1 (PM10: 1272–1697 µg/m3, PM2.5: 1253–1659 µg/m3, PM1: 964–1263 µg/m3) under C2, C4, and C6 (PM10: 68.7–196.2 µg/m3, PM2.5: 68.2–194.7 µg/m3, PM1: 66.1–183.8 µg/m3) C3, C5, and C7 (PM10: 73.7–139 µg/m3, PM2.5: 72–137.9 µg/m3, PM1:68.9–131.9 µg/m3). Vehicle ventilation is insufficient to protect passengers from toxic second-hand smoke completely. Brand-specific variations of tobacco ingredients and mixtures markedly influence PM emissions under ventilation conditions. The most efficient ventilation mode to reduce PM exposure was achieved by opening the passenger´s window 10 cm and turning the onboard ventilation on power level 2/4. In-vehicle smoking should be banned to preserve innocent risk groups (e.g., children) from harm.
Spatiotemporal characteristics of cortical activities of REM sleep behavior disorder revealed by explainable machine learning using 3D convolutional neural network
Authors: Kim Hyun , Seo Pukyeong , Byun Jung-Ick , Jung Ki-Young , Kim Kyung Hwan 
Published: May 2023

AbstractIsolated rapid eye movement sleep behavior disorder (iRBD) is a sleep disorder characterized by dream enactment behavior without any neurological disease and is frequently accompanied by cognitive dysfunction. The purpose of this study was to reveal the spatiotemporal characteristics of abnormal cortical activities underlying cognitive dysfunction in patients with iRBD based on an explainable machine learning approach. A convolutional neural network (CNN) was trained to discriminate the cortical activities of patients with iRBD and normal controls based on three-dimensional input data representing spatiotemporal cortical activities during an attention task. The input nodes critical for classification were determined to reveal the spatiotemporal characteristics of the cortical activities that were most relevant to cognitive impairment in iRBD. The trained classifiers showed high classification accuracy, while the identified critical input nodes were in line with preliminary knowledge of cortical dysfunction associated with iRBD in terms of both spatial location and temporal epoch for relevant cortical information processing for visuospatial attention tasks.
Disinfection of SARS-CoV-2 by UV-LED 267 nm: comparing different variants
Authors: Atari Nofar , Mamane Hadas , Silberbush Alon , Zuckerman Neta , Mandelboim Michal , Gerchman Yoram 
Published: May 2023

AbstractUV irradiation is an efficient tool for the disinfection of viruses in general and coronavirus specifically. This study explores the disinfection kinetics of SARS-CoV-2 variants wild type (similar to the Wuhan strain) and three variants (Alpha, Delta, and Omicron) by 267 nm UV-LED. All variants showed more than 5 logs average reduction in copy number at 5 mJ/cm2 but inconsistency was evident, especially for the Alpha variant. Increasing the dose to 7 mJ/cm2 did not increase average inactivation but did result in a dramatic decrease in the inactivation inconsistency making this dose the recommended minimum. Sequence analysis suggests that the difference between the variants is likely due to small differences in the frequency of specific UV extra-sensitive nucleotide sequence motifs although this hypothesis requires further experimental testing. In summary, the use of UV-LED with their simple electricity need (can be operated from a battery or photovoltaic panel) and geometrical flexibility could offer many advantages in the prevention of SARS-CoV-2 spread, but minimal UV dose should be carefully considered.