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Nonthermal plasmas provide a unique approach to electrically driven heterogeneous catalytic processes. Despite much interest from the community, fundamental activation pathways in these processes remain poorly understood. Here, we investigate how exposure to a nonthermal plasma sustained in an argon nonreactive atmosphere affects the desorption of carbon monoxide (CO) from platinum nanoparticles. Temperature-programmed desorption measurements indicate that the plasma reduces the effective binding energy (BE) of CO to Pt surfaces by as much as ∼0.3 eV, with the reduction in the BE scaling linearly with the plasma density. We find that the effective CO BE is most strongly reduced for under-coordinated sites (steps and edges) compared to well-coordinated sites (terraces). Density functional theory calculations suggest that this is due to plasma-induced charging and electric fields at the catalyst surface, which preferentially affect under-coordinated sites. This study provides direct experimental evidence of plasma-induced nonthermal activation of the adsorbate-catalyst couple.

The hydrogenation of metal nanoparticles provides a pathway toward tuning their combustion characteristics. Metal hydrides have been employed as solid-fuel additives for rocket propellants, pyrotechnics, and explosives. Gas generation during combustion is beneficial to prevent aggregation and sintering of particles, enabling a more complete fuel utilization. Here, we discuss a novel approach for the synthesis of magnesium hydride nanoparticles based on a two-step aerosol process. Mg particles are first nucleated and grown via thermal evaporation, followed immediately by in-flight exposure to a hydrogen-rich low-temperature plasma. During the second step, atomic hydrogen generated by the plasma rapidly diffuses into the Mg lattice, forming particles with a significant fraction of MgH2. We find that hydrogenated Mg nanoparticles have an ignition temperature that is reduced by ∼200 °C when combusted with potassium perchlorate as an oxidizer, compared to the non-hydrogenated Mg material. This is due to the release of hydrogen from the fuel, jumpstarting its combustion. In addition, characterization of the plasma processes suggests that a careful balance between the dissociation of molecular hydrogen and heating of the nanoparticles must be achieved to avoid hydrogen desorption during production and achieve a significant degree of hydrogenation.

Background The goal of the Fifth Annual Baylor College of Medicine & DNAnexus Structural Variation Hackathon was to push forward the research on structural variants (SVs) by rapidly developing and deploying open-source software. The event took place in-person and virtually in August 2023, when 49 scientists from 14 countries and 8 U.S. states collaboratively worked on projects to address critical gaps in the field of genomics. The hackathon projects concentrated on developing bioinformatic workflows for the following challenges: RNA transcriptome comparison, simulation of mosaic variations, metagenomics, Mendelian variation, SVs in plant genomics, and assembly vs. mapping SV calling comparisons. Methods As a starting point we used publicly available data from state-of-the-art long- and short-read sequencing technologies. The workflows developed during the hackathon incorporated open-source software, as well as scripts written using Bash and Python. Moreover, we leveraged the advantages of Docker and Snakemake for workflow automation. Results The results of the hackathon consists of six prototype bioinformatic workflows that use open-source software for SV research. We made the workflows scalable and modular for usability and reproducibility. Furthermore, we tested the workflows on example public data to show that the workflows can work. The code and the data produced during the event have been made publicly available on GitHub ( https://github.com/collaborativebioinformatics) to reproduce and built upon in the future. Conclusions The following sections describe the motivation, lessons learned, and software produced by teams during the hackathon. Here, we describe in detail the objectives, value propositions, implementation, and use cases for our workflows. In summary, the article reports the advancements in the development of software for SV detection made during the hackathon.

IntroductionThe transdiagnostic approach has been shown to offer promising prospects in psychopathology, based on the observation that common factors may be involved in different psychiatric disorders. The transdiagnostic skills scale (T2S) was developed recently to assess the skills that are disrupted in these disorders. However, studies have shown that the T2S has lower predictive power for externalizing than internalizing disorders. This may be due to the fact that the skills assessed do not include the control of urges and cravings. The aims of the current study are thus to develop a revised version of the T2S (T2S-R) integrating this dimension, and to assess its factor structure and invariance across employment status (workers vs. students) and the level of psychopathology.MethodWe recruited 1,298 French participants online through social media. They completed the revised version of the T2S and the symptomatic transdiagnostic test (S2T), which evaluates 11 clusters of psychiatric symptoms. We assessed the factor structure, internal consistency, invariance, and predictive validity of the revised T2S.ResultsWe found a good fit for a bifactor exploratory structural equation modeling (B-ESEM) approach including a global skills factor and seven specific factors. The results also indicate that the new dimension (i.e., control of urges and cravings) has good predictive value, especially for externalizing problems. We also found total invariance of the scale across employment status and partial invariance across the level of psychopathology.ConclusionThe revised version of the T2S-R has good psychometric properties. It predicts better externalizing problems than the original version. However, the scale remains more correlated with internalizing than externalizing problems. We discuss the implications of the results on the transdiagnostic conceptualization and the interest of using a mixed approach combining transdiagnostic and diagnostic analyses.

Hybrid materials comprised of inorganic quantum dots functionalized with small-molecule organic chromophores have emerged as promising materials for reshaping light's energy content. Quantum dots in these structures can serve as light harvesting antennas that absorb photons and pass their energy to molecules bound to their surface in the form of spin-triplet excitons. Energy passed in this manner can fuel upconversion schemes that use triplet fusion to convert infrared light into visible emission. Likewise, triplet excitons passed in the opposite direction, from molecules to quantum dots, can enable solar cells that use singlet fission to circumvent the Shockley-Queisser limit. Silicon QDs represent a key target for these hybrid materials due to silicon's biocompatibility and preeminence within the solar energy market. However, while triplet transfer from silicon QDs to molecules has been observed, no reports to date have shown evidence of energy moving in the reverse direction. Here, we address this gap by creating silicon QDs functionalized with perylene chromophores that exhibit bidirectional triplet exciton transfer. Using transient absorption, we find triplet transfer from silicon to perylene takes place over 4.2 μs while energy transfer in the reverse direction occurs two orders of magnitude faster, on a 22 ns timescale. To demonstrate this system's utility, we use it to create a photon upconversion system that generates blue emission at 475 nm using photons with wavelengths as long as 730 nm. Our work shows formation of covalent linkages between silicon and organic molecules can provide sufficient electronic coupling to allow efficient bidirectional triplet exchange, enabling new technologies for photon conversion.

The quantitative determination of the carbon hybridization is critical for establishing processing-structure-properties relationships for carbon-based materials, including amorphous carbon coatings. While several techniques have been employed to characterize the amount of sp2 and sp3 carbon in these materials, direct comparisons between analytical results are limited. Here, we compare near edge X-ray absorption fine structure (NEXAFS) spectra of a silicon- and oxygen-containing hydrogenated amorphous carbon (a-C:H:Si:O) coating acquired in synchrotron-based scanning transmission X-ray microscopy (STXM) mode with electron energy loss spectra (EELS) obtained from the same a-C:H:Si:O lamella. While the fractions of sp2 carbon computed from STXM and EELS spectra are in close agreement, the comparison of NEXAFS spectra acquired in STXM mode with NEXAFS spectra collected in partial electron yield mode on a flat a-C:H:Si:O surface indicated that the destructive preparation of thin lamellae for STXM analyses induces variations in the structure of a-C:H:Si:O, namely the breakage of carbon-silicon and carbon-hydrogen bonds, a change in ordering of sp2-bonded carbon, and an increase in the sp2 carbon fraction. These findings can help scientists in the careful interpretation of spectroscopic results obtained from the analysis of samples made of metastable materials after the destructive preparation of specimens for analytical purposes.

The rapid spread of SARS-COV-2 and the millions of worldwide deaths and hospitalizations have prompted an urgent need for the development of screening tests capable of rapidly and accurately detecting the virus, even in asymptomatic people. The easy collection and the biomarker content of saliva, together with the label-free and informative power of surface-enhanced Raman spectroscopy (SERS) analysis have driven the creation of point-of-care platforms capable of identifying people with COVID-19. Indeed, different salivary fingerprints were observed between uninfected and infected people. Hence, we performed a retrospective analysis of SERS spectra from salivary samples of COVID-19-infected and -vaccinated subjects to understand if viral components and/or the immune response are implicated in spectral variations. The high sensitivity of the proposed SERS-based method highlighted the persistence of molecular alterations in saliva up to one month after the first positive swab, even when the subject tested negative for the rapid antigenic test. Nevertheless, no specific spectral patterns attributable to some viral proteins and immunoglobulins involved in COVID-19 infection and its progression were found, even if differences in peak intensity, presence, and position were observed in the salivary SERS fingerprint.

Inorganic semiconductor nanocrystals interfaced with spin-triplet exciton-accepting organic molecules have emerged as promising materials for converting incoherent long-wavelength light into the visible range. However, these materials to date have made exclusive use of nanocrystals containing toxic elements, precluding their use in biological or environmentally sensitive applications. Here, we address this challenge by chemically functionalizing non-toxic silicon nanocrystals with triplet-accepting anthracene ligands. Photoexciting these structures drives spin-triplet exciton transfer from silicon to anthracene through a single 15 ns Dexter energy transfer step with a nearly 50% yield. When paired with 9,10-diphenylanthracene emitters, these particles readily upconvert 488-640 nm photons to 425 nm violet light with efficiencies as high as 7 ± 0.9% and can be readily incorporated into aqueous micelles for biological use. Our demonstration of spin-triplet exciton transfer from silicon to molecular triplet acceptors can critically enable new technologies for solar energy conversion, quantum information and near-infrared driven photocatalysis.

NOTCH mutations are frequent in B cell malignancies. Here the authors use retroviral transduction of primary malignant B cells from Chronic Lymphocytic Leukemia (CLL) and Mantle Cell Lymphoma (MCL) patients to show that NOTCH1/2-mutations facilitate mechanism of immune escape.

MYC activation can sensitise cells to apoptosis upon glutamine withdrawal. Here the authors show that MYC activation enhances global transcription and translation that creates a metabolic demand, while glutamine limitation causes a metabolic demand and supply imbalance through loss of TCA energetics and thus, sensitises cells to apoptosis.

Starting point of the article’s thesis is the author's personal experience of theatrical practice and contact with other theatrical cultures, especially in Asia and, even more, in Japan. Aim of the text is to analyse the reasons for the mutual fascination between typically Western theatrical forms and practices, such as what is generically defined as Commedia dell'Arte and others that, equally generically, are defined as Oriental Theatres. This attraction has origins (even if subconscious) that are not only theatrical but rather cultural, or even better, related to cultural visions. The image of the Commedia dell’Arte - a tradition re-invented in the course of the 20th century and made mythical in the collective imagination by the theatrical avant-gardes in the perspective of a profound renewal of European theatre - corresponds to a vision of a generic Theatre of the East, repository of a sort of imaginary purity that has remained uncontaminated and unchanged over the centuries - the so-called living traditions. These theatrical visions are, in turn, the result of the construction of induced cultural identities, of distorted visions of the Other. They are thus part of a cultural imagology that rests on the sedimentation of ideological constructs ranging from mythopoiesis to exoticism, and even corresponds to an induced vision of identity of Japan and Italy. Finally, by returning the discussion to a purely artistic sphere, the importance of the dynamics leading to the hybridisation of languages is assessed, a fertile ground for the connection and construction of cultural bridges and a heuristic practice, moreover, typical of the Commedia dell'Arte, as it made hybridisation its essence, modulating and regenerating itself in European theatres, and not only, from the 16th century onwards.

We report colloidal routes to synthesize silicon@carbon composites for the first time. Surface-functionalized Si nanoparticles (SiNPs) dissolved in styrene and hexadecane are used as the dispersed phase in oil-in-water emulsions, from which yolk-shell and dual-shell hollow SiNPs@C composites are produced via polymerization and subsequent carbonization. As anode materials for Li-ion batteries, the SiNPs@C composites demonstrate excellent cycling stability and rate performance, which is ascribed to the uniform distribution of SiNPs within the carbon hosts. The Li-ion anodes composed of 46 wt % of dual-shell SiNPs@C, 46 wt % of graphite, 5 wt % of acetylene black, and 3 wt % of carboxymethyl cellulose with an areal loading higher than 3 mg cm-2 achieve an overall specific capacity higher than 600 mAh g-1 , which is an improvement of more than 100 % compared to the pure graphite anode. These new colloidal routes present a promising general method to produce viable Si-C composites for Li-ion batteries.

Titanium nitride (TiN) is presented as an alternative plasmonic nanomaterial to the commonly used gold (Au) for its potential use in laser rewarming of cryopreserved biomaterials. The rewarming of vitrified, glass like state, cryopreserved biomaterials is a delicate process as potential ice formation leads to mechanical stress and cracking on a macroscale, and damage to cell walls and DNA on a microscale, ultimately leading to the destruction of the biomaterial. The use of plasmonic nanomaterials dispersed in cryoprotective agent solutions to rapidly convert optical radiation into heat, generally supplied by a focused laser beam, proposes a novel approach to overcome this difficulty. This study focuses on the performance of TiN nanoparticles (NPs), since they present high thermal stability and are inexpensive compared to Au. To uniformly warm up the nanomaterial solutions, a beam splitting laser system was developed to heat samples from multiple sides with equal beam energy distribution. In addition, uniform laser warming requires equal distribution of absorption and scattering properties in the nanomaterials. Preliminary results demonstrated higher absorption but less scattering in TiN NPs than Au nanorods (GNRs). This led to the development of TiN clusters, synthetized by nanoparticle agglomeration, to increase the scattering cross-section of the material. Overall, this study analyzed the heating rate, thermal efficiency, and heating uniformity of TiN NPs and clusters in comparison to GNRs at different solution concentrations. TiN NPs and clusters demonstrated higher heating rates and solution temperatures, while only clusters led to a significantly improved uniformity in heating. These results highlight a promising alternative plasmonic nanomaterial to rewarm cryopreserved biological systems in the future.

Abstract The COVID-19 crisis has taken a significant toll on human life and the global economy since its start in early 2020. Healthcare professionals have been particularly vulnerable because of the unprecedented shortage of Facepiece Respirators (FPRs), which act as fundamental tools to protect the medical staff treating the coronavirus patients. In addition, many FPRs are designed to be disposable single-use devices, creating an issue related to the generation of large quantities of non-biodegradable waste. In this contribution, we describe a plasma-based decontamination technique designed to circumvent the shortages of FPRs and alleviate the environmental problems posed by waste generation. The system utilizes a Dielectric Barrier Discharge (DBD) to generate ozone and feed it through the fibers of the FPRs. The flow-through configuration is different than canonical ozone-based sterilization methods, in which the equipment is placed in a sealed ozone-containing enclosure without any flow through the mask polymer fibers. We demonstrate the rapid decontamination of surgical masks using Escherichia coli (E. coli) and Vesicular Stomatitis Virus (VSV) as model pathogens, with the flow-through configuration providing a drastic reduction in sterilization time compared to the canonical approach. We also demonstrate that there is no deterioration in mask structure or filtration efficiency resulting from sterilization. Finally, we show that this decontamination approach can be implemented using readily available tools, such as a plastic box, a glass tube, few 3D printed components, and the high-voltage power supply from a plasma globe toy. The prototype assembled for this study is portable and affordable, with effectiveness comparable to that of larger and more expensive equipment.