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A thin, wideband transmissive cross polarization converter
Fire-driven disruptions of global soil biochemical relationships
Correction: Exome sequencing reveals IFT172 variants in patients with non-syndromic cholestatic liver disease
Risk factor assessment of prediabetes and diabetes based on epidemic characteristics in new urban areas: a retrospective and a machine learning study
In situ osteogenic activation of mesenchymal stem cells by the blood clot biomimetic mechanical microenvironment
Correction: Factors affecting the relapse of maxilla and soft tissues of nose, upper lip and velopharyngeal structures after maxillary advancement in cleft patients
A study on the effect of blue light on kidney stone formation in rats via the brain-kidney axis
Machine learning photodynamics decode multiple singlet fission channels in pentacene crystal
Abstract Crystalline pentacene is a model solid-state light-harvesting material because its quantum efficiencies exceed 100% via ultrafast singlet fission. The singlet fission mechanism in pentacene crystals is disputed due to insufficient electronic information in time-resolved experiments and intractable quantum mechanical calculations for simulating realistic crystal dynamics. Here we combine a multiscale multiconfigurational approach and machine learning photodynamics to understand competing singlet fission mechanisms in crystalline pentacene. Our simulations reveal coexisting charge-transfer-mediated and coherent mechanisms via the competing channels in the herringbone and parallel dimers. The predicted singlet fission time constants (61 and 33 fs) are in excellent agreement with experiments (78 and 35 fs). The trajectories highlight the essential role of intermolecular stretching between monomers in generating the multi-exciton state and explain the anisotropic phenomenon. The machine-learning-photodynamics resolved the elusive interplay between electronic structure and vibrational relations, enabling fully atomistic excited-state dynamics with multiconfigurational quantum mechanical quality for crystalline pentacene.
Correction: Neural recordings can differentiate between spontaneously metastasizing melanomas and melanomas with low metastatic potential
High sensitivity flexible strain sensor for motion monitoring based on MWCNT@MXene and silicone rubber
Abstract Research on flexible strain sensors has grown rapidly and is widely applied in the fields of soft robotics, body motion detection, wearable sensors, health monitoring, and sports. In this study, MXene was successfully synthesized in powder form and combined with multi-walled carbon nanotube (MWCNT) to develop MWCNT@MXene conductive network-based flexible strain sensors with silicone rubber (SR) substrate. Combining MWCNTs with MXene as a conductive material has been shown to significantly improve the sensor performance, due to MXene’s high conductivity properties that strengthen the MWCNT conductive pathway, increase sensitivity, and improve sensor stability. The sensor is fabricated by a sandwich method consisting of three layers, which enables more accurate and reliable detection of strain changes. The main innovation of this research is the utilization of MWCNT@MXene as a conductive material that optimizes the performance of flexible strain sensors, overcomes the limitations of previous materials, and makes it a more effective solution for long-term applications. Furthermore, the sensor was evaluated to test its performance through sensitivity, linearity, response time, and durability tests. The results showed that the sensor exhibited excellent performance with a high sensitivity of 39.97 over a strain range of 0-100% and excellent linearity (0.99) over a strain of 0–50%. The sensor also has a fast response time of about 70 ms, it also has good stability during low (1–5%) and high (20–100%) strain cycle testing and can withstand up to 1200 loading and unloading cycles. In addition, the sensor effectively detects a wide range of body movements, including finger, wrist and knee movements. These findings show that the electromechanical properties of strain sensors are significantly improved through the use of MWCNT@MXene as a conductive material, so these sensors are considered a promising solution for applications in wearables and body motion monitoring.
Biologists pinpoint neurons that sense how food tastes and feels — in maggots
Coherent harmonic generation of magnons in spin textures
Mechanical properties of a polylactic 3D-printed interim crown after thermocycling
Polylactic acid (PLA) has garnered attention for use in interim dental restorations due to its biocompatibility, biodegradability, low cost, ease of fabrication, and moderate strength. However, its performance under intraoral conditions, particularly under heat and moisture, remains underexplored. This study evaluated the mechanical properties of PLA interim crowns compared with those of polymethylmethacrylate (PMMA) and bisphenol crowns under simulated intraoral conditions with thermocycling. Three CAD/CAM polymers—PMMA (milling), PLA (fused deposition), and bisphenol (stereolithography)—were tested for fracture resistance, hardness, and surface roughness. For fracture strength, 25 crowns from each group were cemented onto dies. The Shore D hardness and surface roughness were measured on round discs before and after 10,000 thermocycles (5°C/55°C). The surface topography was assessed via scanning electron microscopy. PMMA exhibited the highest fracture strength (2787.93 N), followed by bisphenol (2165.47 N) and PLA (2088.78 N), with no significant difference between the latter two. PMMA and bisphenol showed vertical fractures and cracks, whereas PLA showed crown tearing or die deformation. Bisphenol had the highest Shore D hardness, followed by PMMA and PLA, with no significant changes after thermocycling. The surface roughness (Ra) was lowest for bisphenol and similar between PMMA and PLA. The roughness (Rz) increased from bisphenol to PMMA to PLA. The roughness of the PMMA remained unchanged after thermocycling, whereas the Ra but not the Rz of the PLA increased. Bisphenol showed a significant increase in both Ra and Rz (p<0.0001). In conclusion, PLA interim crowns demonstrated mechanical properties comparable to those of conventional PMMA and bisphenol crowns after thermocycling.
Quantitative analysis of amino acid excretion by Methanothermobacter marburgensis under N2-fixing conditions
Abstract Methanogenic archaea (methanogens) possess fascinating metabolic characteristics, such as the ability to fix molecular nitrogen (N2). Methanogens are of biotechnological importance due to the ability to produce methane (CH4) from molecular hydrogen (H2) and carbon dioxide (CO2) and to excrete proteinogenic amino acids. This study focuses on analyzing the link between biological methanogenesis and amino acid excretion under N2-fixing conditions. Among five hydrogenotrophic, autotrophic methanogens, Methanothermobacter marburgensis was prioritized and further cultivated in closed batch cultivation mode under N2-fixing conditions. M. marburgensis was grown on chemically defined minimal medium with different concentrations of ammonium in a H2/CO2/N2 atmosphere. This enabled the quantification of ammonia uptake, N2-fixation, amino acid excretion and the conversion of H2/CO2 to CH4. To quantify N2-fixation rates in a mass balance setting a novel method has been established. The method utilizes the pressure drop below a certain threshold pressure in closed batch cultivation mode – the threshold pressure for N 2 -fixation (THpN2fix). Using the THpN2fix method, volumetric N2-fixation rates of M. marburgensis as high as 0.91 mmol L−1 h−1 were determined. Excretion of amino acids was found with highest detected values of glutamic acid, alanine, glycine and asparagine. The highest total amino acid excretion of 7.5 µmol L−1 h−1 was detected with H2/CO2/N2 at an ammonium concentration of 40 mmol L−1. This study sheds light on the link between methanogenesis, biological N2-fixation, and proteinogenic amino acid excretion. The concomitant production of amino acids and CH4 could become of biotechnological relevance in an integrated approach coupling biomethanation and N2-fixation in a biorefinery concept.
Why it feels good to scratch that itch: the immune benefits of scratching
Advancing the genetic engineering toolbox by combining AsCas12a knock-in mice with ultra-compact screening
Abstract Cas12a is a next-generation gene editing tool that enables multiplexed gene targeting. Here, we present a mouse model that constitutively expresses enhanced Acidaminococcus sp. Cas12a (enAsCas12a) linked to an mCherry fluorescent reporter. We demonstrate efficient single and multiplexed gene editing in vitro, using primary and transformed cells from enAsCas12a mice. We further demonstrate successful in vivo gene editing, using normal and cancer-prone enAsCas12a stem cells to reconstitute the haematopoietic system of wild-type mice. We also present compact, genome-wide Cas12a knockout libraries, with four crRNAs per gene encoded across one (Scherzo) or two (Menuetto) vectors, and demonstrate the utility of these libraries across methodologies: in vitro enrichment and drop-out screening in lymphoma cells and immortalised fibroblasts, respectively, and in vivo screens to identify lymphoma-driving events. Finally, we demonstrate CRISPR multiplexing via simultaneous gene knockout (via Cas12a) and activation (via dCas9-SAM) using primary T cells and fibroblasts. Our enAsCas12a mouse and accompanying crRNA libraries enhance genome engineering capabilities and complement current CRISPR technologies.
Prevalence and antimicrobial resistant Campylobacter spp. in broiler chicken carcasses and hygiene practises in informal urban markets in a low-income setting
Campylobacteriosis is one of the most commonly reported foodborne diseases and is of particular importance in low-income countries. More data is needed to better understand the epidemiology of Campylobacter spp. in food sold at informal markets, where most people in low-income countries buy their food. This study aimed to determine the prevalence and antimicrobial resistance (AMR) of Campylobacter spp. among broiler chicken carcasses sold at informal urban markets in Uganda and to gain more knowledge about hygienic handling practices and awareness of foodborne bacterial diseases among the market vendors. In total, 120 broiler chicken carcasses from 30 different markets were analysed using ISO 10272 and confirmed by PCR. AMR analyses were performed using the disc diffusion test. Epidemiological data on food safety practices and awareness was collected from the vendors using a questionnaire. Campylobacter spp. was isolated from 66% (79/120) of the carcasses; 32% were C. jejuni, 14% were C. coli and 54% comprised of a mixture of both species. All C. jejuni isolates showed resistance to tetracycline, 88% to ciprofloxacin and 28% to erythromycin. Of the C. coli isolates, 82% showed resistance to tetracycline, 73% to erythromycin and the quinolones ciprofloxacin and nalidixic acid. More than half of the vendors had heard about food-borne illnesses, but none knew about Campylobacter spp., and the knowledge regarding hygienic practices was low. These data calls for urgent interventions to improve food safety, protect the public from foodborne illness, and prevent the spreading of AMR.
Effectiveness of iNTS vaccination in sub-Saharan Africa
Abstract Invasive non-Typhoidal Salmonella (iNTS) is one of the leading causes of blood stream infections in Sub-Saharan Africa, especially among children. iNTS can be difficult to diagnose, particularly in areas where malaria is endemic, and difficult to treat, partly because of the emergence of antibiotic resistance. We developed a mathematical model to evaluate the impact of a vaccine for iNTS in 49 countries of sub-Saharan Africa. Without vaccination we estimate 9.2 million new iNTS cases among children below 5 years old in these 49 countries from 2022 to 2038, 6.2 million of which between 2028 and 2038. The introduction of a $$85\%$$ ( $$95\%$$ ) efficacy vaccine in 2028 would prevent 2.6 (2.9) million of these new infections. We provide the country-specific impact of a iNTS vaccine considering the different age structures and vaccine coverage levels.
Observation of ultraviolet photothermoelectric bipolar impulse in gallium-based heterostructure nanowires
New information on Bonapartenykus (Alvarezsauridae: Theropoda) from the Allen Formation (middle Campanian-lower Maastrichtian) of Río Negro Province, Patagonia, Argentina clarifies the Patagonykinae body plan
Alvarezsauria is a group of morphologically distinctive, medium- to small-sized later-diverging coelurosaurian theropod dinosaurs, whose record ranges from the Late Jurassic to the Late Cretaceous. This clade had a widespread distribution in Laurasia in what is now Europe, Asia, and North America, although there are also several Cretaceous taxa from Gondwana in what is now Argentina that all belong to the family Alvarezsauridae. Although alvarezsaurid taxonomic diversity and anatomical knowledge has expanded over the last decade, alvarezsaurid internal phylogenetic relationships remain highly debated. In this contribution, we describe new alvarezsaurid material and review previously reported alvarezsaurid specimens from the middle Campanian—lower Maastrichtian Allen Formation discovered at the Salitral Ojo de Agua locality in Río Negro province, Patagonia, Argentina. Although these specimens were collected at different times without precise original provenance information, here we gathered X-ray diffraction data of the associated sediments that now suggests that all of these specimens come from the same site and stratigraphic level as the holotype of the alvarezsaurid Bonapartenykus ultimus. Based on this new provenance information and the morphological similarity of the considered specimens, here we tentatively refer them to the genus Bonapartenykus. These newly referred specimens add to the record of this genus and shed light on the body plan of the alvarezsaurid clade Patagonykinae by permitting a more complete reconstruction of the neck, pectoral girdle, hindlimb, and tail.