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Space missions necessitate sustainable life support systems capable of producing oxygen and biomass under microgravity conditions. This study examines the use of acoustic levitation to trap and manipulate the filamentous cyanobacterium Limnospira indica PCC 8005 during parabolic flight experiments. We demonstrate that this helicoidal microorganism can be rapidly assembled into thin layers with a standing ultrasonic wave within a millimeter-scale fluidic chamber. Our findings indicate that significantly lower acoustic power is required under microgravity (0.79 mW) compared to terrestrial conditions (1.48 mW) to achieve stable trapping, suggesting energy-efficient bioprocessing in weightless environments. Monte Carlo simulations and light attenuation modelling reveal that structuring cyanobacteria into layered formations enhances light penetration, potentially overcoming the "compensation point" limitation observed in bulk cultures. These results pave the way for advanced photobioreactors that use acoustic manipulation, which improves photosynthetic efficiency and reduces energy consumption for oxygen generation and biomass production in space.

Colloidal nanocrystals are now widely explored for their integration into more advanced electronic and optoelectronic devices. Among the key components enabling this progress is the field-effect transistor (FET). While widely used as a phototransistor, combining both light absorption and gate-induced current modulation, its primary role remains as a tool for extracting material parameters. The electrical output from FETs serves as the main measurement to probe carrier density and mobility in nanocrystal films. However, such an approach suffers from two main flaws: it relies on modeling to link the electrical output to material properties; and second, it can be affected by the presence of defects. Here, we use scanning photoemission microscopy to assess the energy profile in such nanocrystal-based FETs. This method is used to quantify the impact of a local gate defect, which appears to be quite significant, as its impact is stronger and has longer-range effects than the conventional gate operation. We also demonstrate that the method is effective in determining the process at the origin of electrical breakdown. Overall, the method appears well suited to bridge the gap between the material scale and the obtained electrical output and to quantify the impact of potential deviations from ideal behavior.

Acoustic lenses have been introduced recently to compensate for the phase distortions induced by the propagation across a human skull for ultrasonic deep-brain stimulation in humans. In this study, we present bifocal lenses that compensate for human skull aberrations and allow simultaneous targeting of multiple structures deep in the brain. We investigated the impact of phase unwrapping in the design of the lenses and how this process improves the distribution of pressure produced in N=5 human skulls for two different spatial arrangements of the targets. The results show that unwrapping the phase computed during the design increases the fidelity of the pressure field generated across the human skulls. The spatial precision is on average improved by 73%, and out-of-target energy deposition is on average reduced by 58%. The results presented in this study highlight the importance of phase unwrapping to optimize the safety and efficacy of future transcranial ultrasound stimulations targeting multiple regions.

The evolution of multicellular organisms involves the emergence of cellular collectives that eventually become units of selection in their own right. The process can be facilitated by ecological conditions that impose heritable variance in fitness on nascent collectives, with long-term persistence depending on the capacity of competing lineages to transition reliably between soma- and germ-like stages of proto-life cycles. Prior work with experimental bacterial populations showed rapid increases in collective-level fitness, with the capacity to switch between life cycle phases being a particular focus of selection. Here, we report experiments in which the most successful lineage from the earlier study was further propagated for 10 life cycle generations under regimes that required different investments in the soma-like phase. To explore the adaptive significance of switching, a control was included in which reliable transitioning between life cycle phases was abolished. The switch proved central to the maintenance of fitness. Moreover, in a non-switch treatment, where solutions to producing a robust and enduring soma-phase were required, the evolution of mutL-dependent switching emerged de novo. A newly developed computational pipeline (colgen) was used to display the moment-by-moment evolutionary dynamics of lineages, providing rare visual evidence of the roles of chance, history and selection. Colgen, underpinned by a Bayesian model, was further used to propagate hundreds of mutations back through temporal genealogical series, predict lineages and time points corresponding to changes of likely adaptive significance, and in one instance, via a combination of targeted sequencing, genetics and analyses of fitness consequences, the adaptive significance of a single mutation was demonstrated. Overall, our results shed light on the mechanisms by which collectives adapt to new selective challenges and demonstrate the value of genealogy-centred approaches for investigating the dynamics of lineage-level selection.

The most efficient technique for resolving the issue of plastic waste disposal is by converting the wastes into high-quality liquid oils through thermal and catalytic pyrolysis. The objective of this work was to study the composition of liquid oils obtained by thermal and catalytic degradation of plastic wastes containing polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET). The clay catalysts were characterized by N2 adsorption–desorption isotherms (BET), Scanning Electron Microscopy (SEM) and Fourier transform Infrared Spectrometry (FTIR), Polarized Optical Microscopy (POM), Atomic Force Microscopy (AFM). The effect of temperature and clay catalyst type on the yields of the end-products resulting in thermo-catalytic degradation of PS has been evaluated. Degradation of PS showed the highest liquid oil production at 86.85% in comparison to other plastic types. The characterization of the liquid oils was performed by comprehensive two-dimensional gas chromatography coupled with single quadrupole mass spectrometry (GC × GC-qMS). In liquid oils of PS, eighteen principal compounds (of groups: linear hydrocarbons, mono-aromatics, and di-aromatics) were identified. In the liquid oils of the plastic waste mixture, twenty-four principal compounds (of groups: linear hydrocarbons, mono-aromatics, oxygen-containing aromatic, di-aromatics, and tri-aromatics) were identified. The liquid oils were investigated in order to reconvert them as styrene monomers or other chemicals in energy recovery.

A fluorosurfactant is synthesized by the copolymerization of fluoroacrylate and boronic acid acrylamide monomers to stabilize fluorinated oil droplets. The copolymer surfactant couples with diols or polyols in adjacent aqueous...

Substituted azetidines are privileged heterocyclic scaffolds in medicinal chemistry and have become synthetic targets of high interest in recent years. With the goal of developing a new access to azetidines incorporating the pharmaceutically relevant trifluoromethyl group, the reactivity of 2‐(trifluoromethyl)‐1‐azabicyclo[1.1.0]butanes was investigated in polar strain‐release reactions. By using benzyl chloroformate or trifluoroacetic anhydride as reacting partners, diversely substituted 3‐chloroazetidines, 3‐substituted azetidines and azetidin‐3‐ols bearing a trifluoromethyl group at C2 could be readily synthesized. In addition, palladium‐catalyzed hydrogenolysis reactions provided an entry to cis‐3‐aryl‐2‐trifluoromethyl azetidines.

Water repellency is often defined as the territory of contact angles θ larger than 150° and there is some paradox between the huge number of papers devoted to this effect...

Objective. Magnetic resonance guided transcranial focused ultrasound holds great promises for treating neurological disorders. This technique relies on skull aberration correction which requires computed tomography (CT) scans of the skull of the patients. Recently, ultra-short time-echo (UTE) magnetic resonance (MR) sequences have unleashed the MRI potential to reveal internal bone structures. In this study, we measure the efficacy of transcranial aberration correction using UTE images. Approach. We compare the efficacy of transcranial aberration correction using UTE scans to CT based correction on four skulls and two targets using a clinical device (Exablate Neuro, Insightec, Israel). We also evaluate the performance of a custom ray tracing algorithm using both UTE and CT estimates of acoustic properties and compare these against the performance of the manufacturer’s proprietary aberration correction software. Main results. UTE estimated skull maps in Hounsfield units (HU) had a mean absolute error of 242 ± 20 HU (n = 4). The UTE skull maps were sufficiently accurate to improve pressure at the target (no correction: 0.44 ± 0.10, UTE correction: 0.79 ± 0.05, manufacturer CT: 0.80 ± 0.05), pressure confinement ratios (no correction: 0.45 ± 0.10, UTE correction: 0.80 ± 0.05, manufacturer CT: 0.81 ± 0.05), and targeting error (no correction: 1.06 ± 0.42 mm, UTE correction 0.30 ± 0.23 mm, manufacturer CT: 0.32 ± 0.22) (n = 8 for all values). When using CT, our ray tracing algorithm performed slightly better than UTE based correction with pressure at the target (UTE: 0.79 ± 0.05, CT: 0.84 ± 0.04), pressure confinement ratios (UTE: 0.80 ± 0.05, CT: 0.84 ± 0.04), and targeting error (UTE: 0.30 ± 0.23 mm, CT: 0.17 ± 0.15). Significance. These 3D transcranial measurements suggest that UTE sequences could replace CT scans in the case of MR guided focused ultrasound with minimal reduction in performance which will avoid ionizing radiation exposure to the patients and reduce procedure time and cost.

Beta-blockers are pharmaceuticals used to treat cardiovascular diseases such as hypertension, angina pectoris, and arrhythmia. Due to high consumption, they are continuously released into the environment, being detected in many aqueous matrices. The aim of this research is to test the effectiveness of two green liquid-phase microextraction procedures, such as dispersive liquid–liquid microextraction (DLLME) and solidification of floating organic droplet microextraction (SFOME) for the selective extraction of eight beta-blockers (atenolol, nadolol, pindolol, acebutolol, metoprolol, bisoprolol, propranolol, and betaxolol) from aqueous matrices for their analysis by gas chromatography (GC) or liquid chromatography (LC). The influence of extraction parameters, such as the type and volume of extraction and disperser solvents, and ionic strength were studied. The developed extraction procedures provide a good enrichment factor for six compounds (61.22–243.97), good extraction recovery (53.04–92.1%), and good sample cleaning for both extraction procedures. Good limits of detection (0.13 to 0.69 µg/mL for GC and 0.07 to 0.15 µg/mL for HPLC) and limits of quantification (0.39 to 2.10 µg/mL for GC and 0.20 to 0.45 µg/mL for LC) were obtained. The developed procedures were successfully applied to the analysis of selected beta-blockers in wastewater samples, proving their applicability to the real samples.

Activity and autonomous motion are fundamental aspects of many living and engineering systems. Here, the scale of biological agents covers a wide range, from nanomotors, cytoskeleton, and cells, to insects, fish, birds, and people. Inspired by biological active systems, various types of autonomous synthetic nano- and micromachines have been designed, which provide the basis for multifunctional, highly responsive, intelligent active materials. A major challenge for understanding and designing active matter is their inherent non-equilibrium nature due to persistent energy consumption, which invalidates equilibrium concepts such as free energy, detailed balance, and time-reversal symmetry. Furthermore, interactions in ensembles of active agents are often non-additive and non-reciprocal. An important aspect of biological agents is their ability to sense the environment, process this information, and adjust their motion accordingly. It is an important goal for the engineering of micro-robotic systems to achieve similar functionality. Many fundamental properties of motile active matter are by now reasonably well understood and under control. Thus, the ground is now prepared for the study of physical aspects and mechanisms of motion in complex environments, the behavior of systems with new physical features like chirality, the development of novel micromachines and microbots, the emergent collective behavior and swarming of intelligent self-propelled particles, and particular features of microbial systems. The vast complexity of phenomena and mechanisms involved in the self-organization and dynamics of motile active matter poses major challenges, which can only be addressed by a truly interdisciplinary effort involving scientists from biology, chemistry, ecology, engineering, mathematics, and physics. The 2025 motile active matter roadmap of Journal of Physics: Condensed Matter reviews the current state of the art of the field and provides guidance for further progress in this fascinating research area.

RNA interference (RNAi) mediated by the small interfering RNA (siRNA) pathway is a major antiviral mechanism in insects. This pathway is triggered when double-stranded RNA (dsRNA) produced during virus replication is recognized by Dicer-2, leading to the formation of virus-derived siRNA duplexes. These siRNAs are loaded onto the programmable nuclease Argonaute-2 (AGO2), with one strand serving as a guide to target and cleave fully complementary sequences of viral RNAs. While siRNAs are generated from viral dsRNA, the specific viral RNA species targeted for silencing during RNA virus replication remains unclear. In this study, we characterized the primary viral RNA targets of the Drosophila siRNA pathway during infections caused by negative and positive RNA viruses, namely Vesicular stomatitis virus (VSV) and Sindbis virus (SINV). Our findings reveal that polyadenylated transcripts of VSV and SINV are the major targets of silencing by the siRNA pathway during infection, likely when they are poised for translation. Consistent with earlier findings, we show that AGO2 is associated with ribosomes in control and virus infected cells. Therefore, we propose that the inhibition of the replication of RNA viruses in Drosophila results from the silencing of incoming viral transcripts, facilitated by the association of AGO2 with ribosomes.

PURPOSE The objective of this work was to establish prognostic models in stage III colon cancer (CC) on the basis of transcriptomic signatures of the tumor microenvironment (TME) and cell cycle from the PETACC-8 (training set) and IDEA-France (validation set) trials. PATIENTS AND METHODS 3'RNA sequencing was performed in 1,733 patients from the PETACC-8 trial and 1,248 patients from the IDEA-France trial. Four transcriptomic signatures were analyzed: T-cell and macrophage M2 signatures, the expression of CXCL13, and a score on the basis of the Oncotype DX CC Recurrence Score using the same formula from the stromal score and the cell cycle score. The Immune Proliferative Stromal (IPS) score was defined as the number of dichotomized signatures that fall under the category of a dismal prognosis (from 0 to 4). Time to recurrence (TTR) was defined as the time from the date of random assignment to local and/or metastatic relapse and/or death because of CC, whichever occurs first. RESULTS High Oncotype-like and M2 scores and low CXCL13 expression and T-cell score were associated with a shorter TTR. A multivariable model including these signatures and all known prognostic factors applied to the IDEA-France cohort by obtaining a value of this model for each patient showed TTR significantly different depending on the quartile of this value and a 3-year rate of patients without recurrence ranging from 56% for the lowest quartile to 89% for the highest quartile ( P < .0001). The IPS score was significantly associated with TTR in multivariable analysis. CONCLUSION Using transcriptomic data of patients with stage III CC from two large-scale adjuvant trials, a prognostic model on the basis of signatures of the TME and the cell cycle provides important information in addition to known prognostic factors for patient stratification on risk of recurrence.

Autocatalysis, the ability of a chemical system to make more of itself, is a crucial feature in metabolism and is speculated to have played a decisive role in the origin of life. Nevertheless, how autocatalytic systems behave far from equilibrium remains unexplored. In this work, we elaborate on recent advances regarding the stoichiometric characterization of autocatalytic networks, particularly their absence of mass-like conservation laws, to study how this topological feature influences their nonequilibrium behavior. Building upon the peculiar topology of autocatalytic networks, we derive a decomposition of the chemical fluxes, which highlights the existence of productive modes in their dynamics. These modes produce the autocatalysts in net excess and require the presence of external fuel/waste species to operate. Relying solely on topology, the flux decomposition holds under broad conditions and, in particular, does not require steady state or elementary reactions. Additionally, we show that once externally controlled, the nonconservative forces brought by the external species do not act on these productive modes. This must be considered when one is interested in the thermodynamics of open autocatalytic networks. Specifically, we show that an additional term must be added to the semigrand free energy. Finally, from the thermodynamic potential, we derive the thermodynamic cost associated with the production of autocatalysts.

Background NEuroBioStand is an EU‐funded project aimed at developing a metrological research framework for standardising blood‐based biomarkers of neurodegenerative diseases (NDDs) with the objective of implementation and commercialisation of promising assays for NDD biomarkers fulfilling requirements of the in vitro diagnostic regulation (IVDR). P‐tau is currently included in the AT(N) framework for AD diagnosis together with other biomarkers and amyloid‐β and tau in CSF have been developed into regulatory approved biomarkers in CSF. The standardisation of the measurements for this biomarker is important to establish common cut‐off values and reference ranges. Method Recombinant phosphorylated protein and synthetic phosphopeptide materials were sourced as candidate primary calibrators together with their labelled internal standards. Purity was evaluated for the protein and peptide materials by high resolution mass spectrometry coupled to liquid chromatography (LC‐HRMS) and mass fraction was determined by amino acid analysis (AAA). A candidate reference measurement procedure (RMP) is being developed by LC‐HRMS for high accuracy measurement of different phosphorylated epitopes in plasma. Result The first step towards the standardisation of this biomarker is the definition of the measurand: NEuroBioStand consortium has defined the clinically relevant phosphorylated isoforms to develop protein and peptide candidate primary calibrators. P‐tau181, P‐tau217 and P‐tau231 have been prioritized and fit for purpose calibrators have been characterised in terms of purity and mass fraction by amino acids analysis and LC‐MS. In particular, the full characterisation of the phosphorylation status of protein candidate primary calibrators has been carried out to determine the site occupancy of the most relevant phosphorylation sites by using the SI‐traceable quantified phosphorylated peptide materials. The development of a multiplexing SI‐traceable candidate RMP in plasma is in progress with the aim of standardising concentrations of the prioritised phosphorylated epitopes and thus calculating the ratio of phosphorylated to non‐phosphorylated fragments. Conclusion NEuroBioStand consortium gathers national metrology institutes, clinicians, academics and IVD‐providers to achieve traceability to SI units for fluid biomarkers in NDD. The development of a RMP will allow the certification of candidate matrix‐based reference materials that will be used to harmonise measurements of P‐tau in plasma across different analytical platforms, thus standardising cut‐off values and reference ranges.

Cyclobutenones constitute an appealing class of substrates in catalytic asymmetric transformations leading to diversely substituted enantioenriched four‐membered carbocycles, which are eliciting a growing interest in medicinal chemistry. Whilst several synthetically useful enantioselective conjugate addition reactions have been reported, the catalytic enantioselective reduction of the carbonyl group of simple cyclobutenones remains an elusive transformation. Herein, we disclose the discovery of a novel allylic reduction‐asymmetric transfer hydrogenation cascade, catalyzed by a Noyori‐Ikariya ruthenium complex, from readily available gem‐dichlorocyclobutenones, leading to 2‐chlorocyclobutenols with high optical purities, which can be engaged in postfunctionalization reactions enabling access to substituted four‐membered rings.