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Background/Objectives: Protein intake is a key determinant of skeletal muscle health across the lifespan, yet optimal strategies must also account for cardiometabolic health and environmental sustainability. Differences in digestibility and amino acid composition between plant and animal-based proteins may influence their capacity to stimulate muscle protein synthesis (MPS), particularly in aging. Methods: This narrative review integrates evidence from acute tracer studies, randomized controlled trials, and long-term observational research comparing plant versus animal-based proteins for preserving muscle while supporting environmental goals and cardiometabolic health across populations. PubMed and Google Scholar were searched from inception to 11 December 2025 (plant-based protein OR animal-based protein AND sarcopenia OR muscle protein synthesis), with citation tracking. In total, 80 relevant findings were identified. Results: Acute tracer studies show that, gram-for-gram, animal-based proteins (particularly whey/dairy) stimulate greater myofibrillar protein synthesis due to higher leucine density, digestibility, and more rapid aminoacidemia-an effect that is more pronounced in older adults with anabolic resistance. In younger individuals, these differences are largely attenuated when total protein intake is sufficient. Importantly, the anabolic potential of plant-based proteins can be enhanced through higher dosing, amino acid or leucine fortification, and complementary protein blending (e.g., cereals with legumes or use of high-DIAAS isolates). Consistent with this, longer-term resistance training studies demonstrate comparable gains in muscle mass and strength between plant- and animal-based diets when protein intake (≥1.0-1.2 g/kg/day; ≥1.2-1.5 g/kg/day in illness), per-meal distribution (~0.4 g/kg with ~3-4 g leucine in older adults), and energy intake are optimized. Beyond muscle outcomes, higher plant-based protein intake is associated with favorable cardiometabolic profiles and lower environmental impact. Conclusions: An age-specific, mixed protein approach is recommended, emphasizing plant-based proteins in younger adults and higher-quality, leucine-rich proteins in older individuals. Defining optimal plant-to-animal-based protein ratios remains a key research priority.

Oxygenic photosynthesis is driven by visible light in most photosynthetic organisms, with exceptions in a few cyanobacteria and microalgae species, which can extend the light absorption to far-red (FR) wavelengths, by synthesizing new pigments or shifting the antennae absorption range beyond 700 nm. In this work, we describe a novel mechanism of acclimation in the marine microalga Nannochloropsis gaditana, which resulted capable of growth relying solely on FR light. Unexpectedly, the response did not involve the synthesis of red-shifted absorption forms but a peculiar reorganization of chloroplasts. The abundance of photosynthetic complexes changed, with an increased accumulation of all pigment-binding proteins and photosystem II. Chloroplasts became bigger and thylakoid membranes increased in number, occupying almost all the organelle volume, showing also newly observed structures, composed of a central superstack with perpendicular electron-dense interconnections, that we propose to name thylakoidal bodies. To the best of our knowledge, these results describe a novel acclimation strategy to FR light, overall highlighting that the biodiversity of responses to FR light is currently underestimated.

Expanding the Stokes shift of lead-halide perovskite nanocrystals (NCs) without compromising their sharp, fast excitonic emission has remained elusive, as high halide mobility erases the compositional gradients required for stable core/shell architectures. Here, it is shown that introducing a CdCl2 passivation step prior to halide exchange provides a simple solution. Treating CsPbCl3 NCs with CdCl2 eliminates halide-vacancy traps, enhances emission yield, and crucially blocks inward diffusion of I-, arresting the Cl- → I- exchange after just a few monolayers. This produces CsPbCl3/CsPbI3 core/shell NCs that absorb at 3.14 eV from the core and emit at 1.91 eV from the shell, achieving an apparent Stokes shift of ≈1.2 eV. The heterostructures exhibit ≈70% photoluminescence quantum yield, fast emission lifetime (≈10 ns) and complete suppression of reabsorption losses, as confirmed by liquid-waveguiding experiments. Transient absorption spectroscopy and DFT modeling reveal an inverted type-I band alignment with ultrafast (≈60 ps) core-to-shell exciton transfer. This fully solution-processed chemistry enables heterostructuring-based wavefunction engineering - long employed to expand the capabilities of conventional quantum dots - now realized in perovskite NCs, which provides a practical route to reabsorption-free perovskite emitters for advanced photonic and quantum technologies.

Plants are critical for sustaining human life and planetary health. However, their potential to enable humans to survive and thrive beyond Earth remains unrealized. This Viewpoint presents a collective vision outlining priorities associated with plant science to support a new frontier of human existence. These priorities are drawn from the International Space Life Sciences Working Group (ISLSWG) Plants for Space Exploration and Earth Applications workshop, held at the European Low Gravity Research Association (ELGRA) conference in September 2024. First, we highlight transformative advances gained from using the 'laboratory of space' in understanding how plants respond to gravity and other stressors. Second, we introduce a new crop Bioregenerative Life Support System (BLSS) readiness level (BRL) framework - extending the existing Crop Readiness Level (CRL) - to assist in overcoming challenges to establish resilient, sustainable crop production. Materializing the vision of plants as enablers of space exploration will require innovative approaches, including predictive modeling, synthetic biology, robust Earth-based analogue systems, and reliable space-based instruments to monitor biological processes. Success relies upon a unified international community to promote sharing of resources, facilities, expertise, and data to accelerate progress. Ultimately, this work will both advance human space exploration and provide solutions to enhance sustainable plant production on Earth.

The Trinity nuclear test of July 16, 1945, generated extreme transient conditions that produced trinitite, a silicate glass containing rare metallic phases. Here we report the discovery and structural and chemical characterization of a previously unknown Ca-Cu-Si type-I clathrate, (Ca3.3Cu0.4Fe0.3)Σ=4Si23, identified within a Cu-rich metallic droplet embedded in red trinitite. Single-crystal X-ray diffraction shows that this phase adopts the cubic clathrate-I topology, representing the first crystallographically confirmed clathrate structure documented among the solid-state products of a nuclear explosion. Beyond its intrinsic significance, this phase is notable for its close contextual association with the previously reported Si-rich icosahedral quasicrystal formed in the same detonation. Both phases formed under identical extreme conditions, occur within similar Cu-rich droplets, and share an unusually Si-rich Ca-Cu-Si-(Fe) chemistry, motivating an evaluation of whether the quasicrystal could be structurally derived from a clathrate framework. To evaluate this possibility, we performed density functional theory calculations on clathrate-based icosahedral models across a range of Cu contents. The results indicate that clathrate-derived icosahedral structures are mechanically plausible and metastable at low Cu concentrations (~10 to 11%) but become unstable as Cu content approaches that of the Trinity quasicrystal. These findings constrain viable structural models for the quasicrystal and argue against a simple clathrate-derived interpretation.

Relativistic jets from supermassive black holes in active galactic nuclei are amongst the most powerful phenomena in the universe. Similar jets from stellar-mass black holes offer a chance to study the phenomena on accessible observation time scales. However, such comparative studies across black hole masses and time scales remain hampered by the long-standing perception that stellar-mass black hole jets are in a less relativistic regime. Here, we show the detection of two distinct, relativistic jet ejections from the Galactic black hole X-ray binary 4U 1543-47 during a single outburst, with radio interferometry monitoring observations. Our measurements reveal a likely Lorentz factor of approximately 8 and a minimum of 4.6 at launch with 95% confidence, demonstrating that stellar-mass black holes in X-ray binaries can launch jets as relativistic as those seen in active galactic nuclei.

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Among ground-based paradigms used to reproduce altered gravity exposure, the hindlimb unloading (HU) model is widely employed to simulate microgravity conditions by removing gravitational loading from the hindlimbs. Despite its extensive use, behavioral adjustments during suspension remain poorly characterized, although they may provide valuable indicators of animal welfare and individual susceptibility. Here, we comprehensively characterized the behavioral profile of mice during and after HU using a dedicated ethogram, with the aim of identifying behavioral markers associated with individual coping strategies. Several exploratory and postural behaviors showed marked time-dependent modulation, with baseline exploratory activity predicting a more adaptive behavioral trajectory during suspension, possibly indicative of greater resilience. In parallel, brain levels of the neurotrophins NGF and BDNF were measured to explore their relationship with behavioral outcomes. Although no significant group differences were detected, suspended mice displayed a progressive reduction in both neurotrophins over time, which paralleled behavioral adaptation. Together, these findings indicate that specific exploratory behaviors represent reliable predictors of resilience to HU, while NGF and BDNF may reflect ongoing neuroplastic processes associated with prolonged suspension.

Exposure to microgravity and cosmic radiation during spaceflight is responsible for oxidative stress onset, contributing to neuronal dysfunction and degeneration. The central nervous system is particularly vulnerable to redox imbalance and requires effective countermeasures to ensure astronaut health and performance on long-duration missions. In this study, the neuroprotective properties of polydopamine nanoparticles (PDNPs), known for their antioxidant activity, are investigated on neuron-like cells exposed to different gravitational and radiation regimes. Culture conditions included administration of PDNPs and permanence aboard the International Space Station (ISS) or on a random positioning machine. Transcriptomic analyses are conducted to assess gene expression alterations associated with oxidative stress, nuclear and mitochondrial integrity, and dopamine metabolism. In-flight, PDNP treatment mitigates the transcriptional changes induced by space stressors, preserving neuronal homeostasis. Notably, expression of key antioxidant defense genes, mitochondrial function markers and dopamine metabolism genes is stabilized in PDNP-treated neurons. This study provides preliminary evidence on the efficacy of PDNPs in protecting neuronal cells from the combined stressors associated with spaceflight: these findings suggest PDNPs as a promising countermeasure for space-induced neurodegeneration and support their potential translational application in the treatment of oxidative stress-related neurodegenerative pathologies on Earth.

Intense volcanism has played a significant role in shaping Venus's surface and geology. The existence of lava tubes (i.e., pyroducts) on Venus has been largely hypothesized but never confirmed. Being a subsurface structure, the presence of a lava tube can be revealed by a localized collapse of the roof denoted as skylight. Between 1990 and 1992, the Synthetic Aperture Radar (SAR) instrument on board the Magellan spacecraft mapped the Venusian surface. By leveraging a SAR imaging technique developed for detecting and characterizing accessible subsurface conduits in the proximity of skylights, we analysed the Magellan radar images in locations where there is evidence of localized surface collapses. Our analyses reveal the existence of a large and open subsurface conduit in the Nyx Mons region. This feature is hypothesized to be a pyroduct, characterized by a diameter of about 1 km, a roof thickness of at least 150 m and an empty void height of no less than 375 m. The conduit extends in the subsurface for at least 300 meters from the skylight.

As space missions extend in duration and distance, there is an increasing need for autonomous life-support systems capable of recycling resources and producing essential compounds in situ. In this context, alginate-entrapped microalgae were used to assess growth under reduced liquid conditions, testing two different beads-to-volume ratios (1:1 and 1:2). In batch cultures conducted in flasks without aeration, the immobilized microalgae using HEPES-Acetate-Phosphate (HAP) medium reached a maximum dry weight (DW) of 0.93 ± 0.03 g/L and 33.65 ± 1.19 x 106 cells/mL in the 1:2 configuration, compared to 1.01 ± 0.02 g/L and 37.44 ± 1.56 x 106 cells/mL in suspension. Biomass productivity peaked at 404 mg/(L·d) for suspension and 240 mg/(L·d) for 1:2 immobilized cultures. Biochemical analysis of immobilized biomass revealed high nutritional value, with up to 32.5 % DW lipids, 23.6 % DW proteins, and 12.5 % DW carbohydrates. In the pre-prototype column reactor with medium recirculation and air bubbling, microalgae showed lower productivity than in batch tests indicating the need for further optimization of process configuration. Immobilized Chlorella vulgaris offers a trade-off between reduced productivity and engineering advantages, such as ease of recovery, and suitability for automated, closed-loop bioregenerative in space life-support systems as well as for terrestrial application.

Hypomyelinating leukodystrophies (HLDs) are rare genetic neurodevelopmental disorders characterized by defective myelin formation. The genetic cause of these disorders has been ascribed to mutations in genes encoding myelin protein components, such as proteolipid protein 1 (PLP1) and myelin basic protein (MBP), or in genes encoding for transcription and translation-related proteins. Particularly, biallelic pathogenic variants in POLR3A, POLR3B, POLR3K, POLR3D, POLR1C lead to the insurgence of RNA Polymerase III (Pol III)-related HLDs (POLR3-HLDs). The molecular mechanisms linking Pol III dysfunction to hypomyelination remain largely elusive, though the main hypothesis is that impaired Pol III activity likely disrupts gene expression and cellular homeostasis processes critical for myelin development and lipid metabolism. In this study, we analyzed a family trio consisting of unaffected carrier parents and a proband affected by POLR3A-related HLD, carrying compound heterozygous variants (p.Phe601Tyr and p.Gly1358Arg). We investigated the structural and functional consequences of two POLR3A variants using protein modeling, functional assays and multi-omics profiling in subject-specific primary fibroblasts. Structural analysis revealed alterations in DNA-binding regions and a likely impact on protein stability, whilst functional assays showed an impairment in cellular proliferation. Lipidomic and transcriptomic profiling revealed that p. Gly1358Arg mutation predominantly affects lipidomic metabolism, while p. Phe601Tyr was associated with a widespread transcriptional dysregulation. Both mutations ultimately caused a significant reduction in lipid droplets in the proband's cells. These results demonstrate mutation-specific pathogenetic mechanisms in POLR3A-HLD and underline the utility of integrative multi-omics approaches in elucidating the molecular basis of rare neurodevelopmental disorders.

Dual-comb spectroscopy is one of the most powerful techniques for multispecies trace-gas sensing, attracting growing attention in both theoretical and experimental research. Firstly demonstrated and usually applied with direct absorption spectroscopy schemes, the dual-comb approach has been successfully combined with techniques like photoacoustic (PA) and photothermal (PT) spectroscopy in recent years. These techniques have been demonstrated to be particularly attractive because of their wavelength-independent and background-free detection, two key features allowing for the achievement of unprecedented dynamic range and flexibility. The integration of these techniques with dual-comb spectroscopy allows a significant enhancement in spectral resolution and bandwidth while preserving the peculiar features of PA and PT spectroscopy. Since the first proof-of-principle demonstration of dual-comb PA spectroscopy, several solutions based on acoustic transducers and optical cavities have been proposed to enhance the final sensitivity and optimize both detection bandwidth and spectral resolution. Starting from the description of the physical principles behind dual-comb PA and PT spectroscopy, this work presents a comprehensive review of the available state-of-the-art, focusing both on the different experimental setups and on a systematic comparison of the achieved results. Finally, the main challenges and prospects will be discussed, offering insights into potential directions for further innovation.

Halide exchange in lead-based halide perovskites has been studied extensively. While mixed Cl/Br or Br/I alloy compositions can be formed with no miscibility gaps, this is precluded for mixed Cl/I compositions, due to the large difference in Cl- and I- ionic radii. Here, perovskite-chalcohalide CsPbCl3-Pb4S3Cl2 nanocrystal heterostructures are exploited to study the Cl→I exchange and to isolate new types of intermediate structures. The epitaxial interface between the Pb4S3Cl2 chalcohalide and the CsPbCl3 perovskite significantly influences the intermediate stages of halide exchange in the perovskite domain, leading to coexisting CsPbCl3 and CsPbI3 domains, thereby delivering segmented CsPbI3-CsPbCl3-Pb4S3Cl2, energetically favorable heterostructures, with partial I-alloying of the CsPbCl3 domain and at the perovskite-chalcohalide interface. The I:CsPbCl3 domain between CsPbI3 and Pb4S3Cl2 enables a gradual lattice expansion across the heterostructure. This design accommodates interfacial strain, with a 5.6% mismatch at the CsPbCl3-CsPbI3 interface and a 3.4% mismatch at the perovskite-chalcohalide interface. Full halide exchange leads to CsPbI3-Pb4S3Cl2 heterostructures. Both in intermediate and fully exchanged heterostructures, the CsPbI3 domain is emissive. In the intermediate structures, the band alignment between the two perovskite domains is type-I, with the carriers photogenerated in the CsPbCl3 domain quickly transferring to the CsPbI3 domain, where they can recombine radiatively.

Myelosuppression is a common secondary manifestation of sepsis and is associated with increased morbidity and mortality. Recent evidence suggests that amino acid metabolism, particularly that of glutamic acid, may influence hematopoietic function and inflammatory responses1. Using a machine learning technique, we aimed to evaluate whether plasma amino acid levels at hospital admission are associated with myelosuppression and 30-day mortality in septic patients, with a focus on glutamic acid as a potential early biomarker. We conducted a prospective observational study on 390 adult patients hospitalized with sepsis at the University Hospital of Trieste. Patients were stratified into two groups on the basis of peripheral blood counts: myelosuppressed and non-myelosuppressed. Plasma levels of 13 amino acids were quantified at admission via high-performance liquid chromatography. Inflammatory markers, clinical outcomes, and 30-day mortality were recorded. Predictive models for myelosuppression were developed via Random Forest and interpreted via SHapley Additive exPlanations (SHAP) analysis. While nutritional intake and longitudinal amino acid trends were not available, we accounted for major comorbidities in the analysis. Myelosuppression was identified in 152 patients (39%) and was associated with significantly higher levels of inflammatory markers (e.g., C-reactive protein (CRP) and procalcitonin), an increased incidence of bacteremia, and increased 30-day mortality (20% vs. 12%, p = 0.03). Patients experiencing myelosuppression had lower median glutamic acid concentrations (134 vs. 154 µmol/L, p = 0.05). Among the 44 clinical and metabolic features, glutamic acid was the strongest predictor according to SHAP analysis. Furthermore, glutamic acid concentrations less than 134 µmol/L were associated with reduced survival according to Kaplan Meier analysis (p = 0.013). Reduced plasma glutamic acid levels at admission are independently associated with myelosuppression and worse prognosis in septic patients. Although causality cannot be established and nutritional/temporal factors were not captured, glutamic acid may represent an early biomarker for risk stratification and deserves further investigation in longitudinal and interventional studies.

We have explored the reactions of a three-components mixture made of formamide, diaminomaleonitrile, and glycine, with meteorites as catalysts and high-energy proton beam irradiation as the energy source, mimicking the solar wind. The resulting mixture contained a wide array of biogenic compounds, including the complete set of RNA nucleobases and nucleosides, thymine and its analogs, pterins, triazines, carboxylic acids, diketopiperazines, hydantoins, N-carboxyamino acid anhydrides, amino acids, peptides, and nucleobase-amino acid/peptide conjugates. It also embodies the possibility of synthesis stability of RNA-peptide chimeras onto which evolution to the extant molecular genetic system could start. The prebiotic worth of the system consists of the fact that formamide derives from HCN hydrolysis; glycine is a condensation product of formamide and HCN; diaminomaleonitrile is obtained from HCN. The fact that the starting mixture is three-component does not decrease the prebiotic value; it is a subset of a largely possible general universal condition: all the starting components are only the second step of facile condensation reactions. This model could be the starting point for the chemical evolution towards biological complexity.

This work presents an original implementation of the digital sampling pipeline for spaceborne Fourier Transform Spectrometers (FTSs). The implementation aims at improving the robustness of the spectrometer to harsh environmental conditions, including mechanical vibrations and a wide operational temperature range, avoiding the use of dedicated electronic hardware for the interferometer mirrors' speed control and interferogram sampling. The FTS configuration is based on the constant time step sampling of the interferometer using a standard ADC (Analogue to Digital Converter), along with two metrology laser channels. The development tool is a MATLAB-based simulator developed to emulate the FTS and, in particular, the generation and acquisition of interferograms, incorporating harmonic vibrations and detector noise. The simulator was exploited to compare state-of-the-art techniques and newly implemented variants. An improvement of the arccosine method is first proposed, revising the normalisation process to exploit the full set of recorded data without discarding critical points. Subsequently, methods using two reference channels have been developed and evaluated. Two implementations are considered: two references at the same wavelength with an optimised phase shift (i.e., π/2) and two references at different wavelengths. Different data fusion strategies are compared in terms of spectral uncertainty, varying types of simulated disturbances and noise amplitudes. Results show that the optimal combination of two same-wavelength references consistently outperforms any other configuration, yielding lower average spectral errors and more stable performance over the frequency range and for a lower SNR of reference channels. Conversely, dual-wavelength strategies exhibit reduced accuracy, though they offer flexibility when fixed phase shifts cannot be maintained. The optimal combination of two same-wavelength reference channels, phase-shifted, is a promising configuration for spaceborne FTSs, so the development and test of an instrument breadboard is envisaged as the consequent development of this work.

The Middle-Wave Infrared Imaging Spectrometer for Target Asteroids (MIST-A) will be launched in 2028 aboard the Emirates Mission to the Asteroid belt (EMA) and will operate in the 2-5 μm spectral range to study the asteroids' surface composition and thermo-physical properties. MIST-A's Optical Head (OH) design is inherited from the Jovian IR Auroral Mapper (JIRAM), from which the instrument also received two spare Hybrid-Thinned Mercury-Cadmium-Telluride (MCT) photodetectors: the Engineering Model EM2 and the Flight Spare FS1. These are tested to assess their performance after a long period of storage. The laboratory setup for testing both detectors consists of a blackbody and a cryostat which houses the focal plane, maintained at temperatures of 85 K, its nominal operative temperature, and 90 K. Two sets of measurements are performed: (1) characterization of the dark current at different integration times (0 ms, 224 ms, 448 ms, 672 ms, 869 ms, 1120 ms); (2) verification of the detectors' response linearity, measuring a blackbody at different temperatures (from 50 °C to 100 °C), including ambient temperature (25 °C, with the blackbody turned off). The results of these tests confirm that both models are fully operational and allow us to evaluate the consequences of the years of inactivity on their performance. Through a detailed analysis of the detectors' properties and a comparison study with the results of the sensors' first characterization performed by their producer in 2009, we come to the conclusion that both instruments are able to fulfill MIST-A's scientific requirements. The FS1 displays a better performance with respect to the EM2 and for this has been selected as MIST-A's Flight Model.

Reconstructing chemical variations of magma during rifting is challenging due to the heterogeneous mantle sources of the melt and different evolution pathways that magma potentially takes. Therefore, how and when the magma generation process evolves to that typical of an oceanic ridge (MORB-like composition) is still unclear. The Afar depression is an ideal place for studying magma changes during rift evolution, with North Afar close to breakup and older rift products preserved across the region. To investigate magma sources, we applied clustering analyses to a vast geochemical dataset of more than 1000 samples from the Afar rift. Combinations of different clustering methods (K-means and hierarchical) and assessment of correlation between features (Pearson coefficient) show that both trace element and isotope clustering group the North Afar samples, identifying a mantle source containing residual MREE-bearing minerals and an enriched mantle component. This suggests that North Afar, where the rift is closest to breakup, has a stronger influence of the Afar plume and more extensive partial melting of metasomatized lithosphere than the rest of Afar. We show that geochemical variations during rifting do not always follow a progressive transition toward a MORB-like composition but, instead, plume-like magmatism can increase until the most advanced stages of rifting (i.e., North Afar), potentially because the mantle plume is focused towards regions of thinnest lithosphere. The online version contains supplementary material available at 10.1038/s41598-026-35961-0.