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In a self-similar paradigm of structure formation, the thermal pressure of the hot intra-cluster gas follows a universal distribution once the profile of each cluster is normalised based on the proper mass and redshift dependencies. The reconstruction of such a universal pressure profile requires an individual estimate of the mass of each cluster. In this context, we present a method to jointly fit, for the first time, the universal pressure profile and individual cluster \\(M_{500}\\) masses over a sample of galaxy clusters, properly accounting for correlations between the profile shape and amplitude, and masses scaling the individual profiles. We demonstrate the power of the method and show that a consistent exploitation of the universal pressure profile and cluster mass estimates when modelling the thermal pressure in clusters is necessary to avoid biases. In particular, the method, informed by a cluster mass scale, outputs individual cluster masses with same accuracy and better precision than input masses. Using data from the {\\guillemotleft}Cluster HEritage project with XMM-Newton: Mass Assembly and Thermodynamics at the Endpoint of structure formation{\\guillemotright}, we investigate a sample of \\(\\sim 25\\) galaxy clusters spanning mass and redshift ranges of \\(2 \\lesssim M_{500}/10^{14} \\; \\mathrm{M}_{\\odot} \\lesssim 14\\) and \\(0.07 < z < 0.6\\).

Mitochondria organize their genome in protein–DNA complexes called nucleoids. The mitochondrial transcription factor A (TFAM), a protein that regulates mitochondrial transcription, is abundant in these nucleoids. TFAM is believed to be essential for mitochondrial DNA compaction, yet the exact mechanism has not been resolved. Here we use a combination of single-molecule manipulation and fluorescence microscopy to show the nonspecific DNA-binding dynamics and compaction by TFAM. We observe that single TFAM proteins diffuse extensively over DNA (sliding) and, by collisions, form patches on DNA in a cooperative manner. Moreover, we demonstrate that TFAM induces compaction by changing the flexibility of the DNA, which can be explained by local denaturation of the DNA (melting). Both sliding of TFAM and DNA melting are also necessary characteristics for effective, specific transcription regulation by TFAM. This apparent connection between transcription and DNA organization clarifies how TFAM can accomplish two complementary roles in the mitochondrial nucleoid at the same time. The mitochondrial transcription factor A (TFAM) mediates both mitochondrial transcription and DNA compaction, but how it achieves these two functions is unknown. In this study, TFAM is shown to slide along DNA and cause local melting, suggesting a mechanism for how TFAM modulates both transcription and compaction.

Within the self-similar framework of structure formation, the thermal pressure of the hot intra-cluster medium follows a universal distribution that is independent of the cluster mass scale. Once normalised to the proper mass and redshift dependencies, this pressure distribution becomes common to all clusters. Reconstructing such a universal pressure profile requires individual estimates of each cluster’s mass. In this work, we present a methodology to simultaneously fit the universal pressure profile alongside the masses of individual clusters in a sample, while properly accounting for correlations between the profile’s shape, its amplitude, and cluster masses. We apply this method to a sub-sample of clusters from the CHEX-MATE project and demonstrate the strong impact that the assumed pressure profile has on the measured signal. This effect propagates into the thermal Sunyaev-Zel’dovich (tSZ) power spectrum and, in turn, influences the determination of cosmological parameters.

Supermassive black holes and supernova explosions at the centres of active galaxies power cycles of outflowing and inflowing gas that affect galactic evolution and the overall structure of the Universe 1 , 2 . While simulations and observations show that this must be the case, the range of physical scales (over ten orders of magnitude) and paucity of available tracers make both the simulation and observation of these effects difficult 3 , 4 . By serendipity, there lies an active galaxy, Centaurus A (NGC 5128) 5 , 6 , at such a close proximity as to allow its observation over this entire range of scales and across the entire electromagnetic spectrum. In the radio band, however, details on scales of 10–100 kpc from the supermassive black hole have so far been obscured by instrumental limitations 7 , 8 . Here we report low-frequency radio observations that overcome these limitations and show evidence for a broad, bipolar outflow with velocity of 1,100 km s −1 and mass-outflow rate of 2.9  M ⊙  yr −1 on these scales. We combine our data with the plethora of multiscale, multi-wavelength, historical observations of Centaurus A to probe a unified view of feeding and feedback, which we show to be consistent with the chaotic cold accretion self-regulation scenario 9 , 10 . Previously unresolved radio features of nearby Centaurus A reveal transition regions for both the feeding of this active galaxy and the feedback mechanism for recycling energy back into the surrounding medium.

The pseudorapidity density and multiplicity distribution of charged particles produced in proton-proton collisions at the LHC, at a centre-of-mass energy $\\sqrt{s}=7$ TeV, were measured in the central pseudorapidity region |η| < 1. Comparisons are made with previous measurements at $\\sqrt{s}=0.9$ TeV and 2.36 TeV. At $\\sqrt{s}=7$ TeV, for events with at least one charged particle in |η| < 1, we obtain dNch/dη = 6.01 ± 0.01(stat.)$\\mathbb +0.20\\atop{-0.12} $(syst.). This corresponds to an increase of 57.6% ± 0.4%(stat.)$\\mathbb +3.6\\atop{-1.8} $(syst.) relative to collisions at 0.9 TeV, significantly higher than calculations from commonly used models. The multiplicity distribution at 7 TeV is described fairly well by the negative binomial distribution.

Supermassive black hole accretion and feedback play central role in the evolution of galaxies, groups, and clusters. I review how AGN feedback is tightly coupled with the formation of multiphase gas and the newly probed chaotic cold accretion (CCA). In a turbulent and heated atmosphere, cold clouds and kpc-scale filaments condense out of the plasma via thermal instability and rain toward the black hole. In the nucleus, the recurrent chaotic collisions between the cold clouds, filaments, and central torus promote angular momentum cancellation or mixing, boosting the accretion rate up to 100 times the Bondi rate. The rapid variability triggers powerful AGN outflows, which quench the cooling flow and star formation without destroying the cool core. The AGN heating stifles the formation of multiphase gas and accretion, the feedback subsides and the hot halo is allowed to cool again, restarting a new cycle. Ultimately, CCA creates a symbiotic link between the black hole and the whole host via a tight self-regulated feedback which preserves the gaseous halo in global thermal equilibrium throughout cosmic time.

Silver nanoparticles (AgNPs) have been broadly used as antibacterial and antiviral agents. Further, interests for green AgNP synthesis have increased in recent years and several results for AgNP biological synthesis have been reported using bacteria, fungi and plant extracts. The understanding of the role and nature of fungal proteins, their interaction with AgNPs and the subsequent stabilization of nanosilver is yet to be deeply investigated. Therefore, in an attempt to better understand biogenic AgNP stabilization with the extracellular fungal proteins and to describe these supramolecular interactions between proteins and silver nanoparticles, AgNPs, produced extracellularly by Aspergillus tubingensis —isolated as an endophytic fungus from Rizophora mangle— were characterized in order to study their physical characteristics, identify the involved proteins, and shed light into the interactions among protein-NPs by several techniques. AgNPs of around 35 nm in diameter as measured by TEM and a positive zeta potential of +8.48 mV were obtained. These AgNPs exhibited a surface plasmon resonance (SPR) band at 440 nm, indicating the nanoparticles formation, and another band at 280 nm, attributed to the electronic excitations in tryptophan, tyrosine, and/or phenylalanine residues in fungal proteins. Fungal proteins were covalently bounded to the AgNPs, mainly through S–Ag bonds due to cysteine residues (HS–) and with few N–Ag bonds from H 2 N– groups, as verified by Raman spectroscopy. Observed supramolecular interactions also occur by electrostatic and other protein–protein interactions. Furthermore, proteins that remain free on AgNP surface may perform hydrogen bonds with other proteins or water increasing thus the capping layer around the AgNPs and consequently expanding the hydrodynamic diameter of the particles (~264 nm, measured by DLS). FTIR results enabled us to state that proteins adsorbed to the AgNPs did not suffer relevant secondary structure alteration upon their physical interaction with the AgNPs or when covalently bonded to them. Eight proteins in the AgNP dispersion were identified by mass spectrometry analyses. All these proteins are involved in metabolic pathways of the fungus and are important for carbon, phosphorous and nitrogen uptake, and for the fungal growth. Thereby, important proteins for fungi are also involved in the formation and stabilization of the biogenic AgNPs.

Background/Objectives: Malnutrition, systemic inflammation, and immune dysfunction are key determinants of adverse outcomes in older adults following acute illness. Composite biomarkers integrating these domains could enhance early risk stratification. This study investigates, for the first time in acute geriatric care, the prognostic value of the C-reactive protein–albumin–lymphocyte (CALLY) index—a composite marker of nutritional, inflammatory, and immune status—in predicting short-term survival. Methods: We retrospectively analyzed 264 patients admitted to the acute geriatrics ward of Santa Maria della Misericordia Hospital in Perugia. The CALLY index was calculated as: (Albumin × Lymphocytes)/(CRP × 104). The optimal prognostic cut-off was determined using receiver operating characteristic (ROC) curve analysis. Three-month survival was assessed by Kaplan–Meier analysis. Results: The cohort included 167 women (63.3%) and 97 men (36.7%), with a mean age of 88.0 ± 6.4 years. At 3-month follow-up, 80 patients (30.3%) had died. The CALLY index showed an area under the ROC curve of 0.647 (95% CI: 0.576–0.718; p < 0.001), with a cut-off of 0.055 (sensitivity: 68.5%, specificity: 46.3%). Among deceased patients, 42.5% had a CALLY index <0.055. After multivariable adjustment, a lower CALLY index remained independently associated with increased mortality (B = −0.805; OR = 0.45; 95% CI: 0.215–0.930; p = 0.031). Kaplan–Meier analysis demonstrated significantly higher survival in patients with a CALLY index ≥ 0.055 (Log-rank test: 13.71; p < 0.001). Conclusions: The CALLY index shows a modest but statistically significant discriminative ability for predicting short-term mortality in acutely ill older adults. As a simple, low-cost marker derived from routine laboratory tests, it holds potential for integration into clinical workflows to guide nutritional, metabolic, and prognostic management strategies in geriatric acute care.

Characterization of the basic transcription machinery of mammalian mitochondrial DNA (mtDNA) 1 , 2 is of fundamental biological interest and may also lead to therapeutic interventions for human diseases associated with mitochondrial dysfunction 3 , 4 , 5 , 6 . Here we report that mitochondrial transcription factors B1 (TFB1M) and B2 (TFB2M) are necessary for basal transcription of mammalian mitochondrial DNA (mtDNA). Human TFB1M and TFB2M are expressed ubiquitously and can each support promoter-specific mtDNA transcription in a pure recombinant in vitro system containing mitochondrial RNA polymerase (POLRMT) 7 and mitochondrial transcription factor A 8 , 9 . Both TFB1M and TFB2M interact directly with POLRMT, but TFB2M is at least one order of magnitude more active in promoting transcription than TFB1M. Both factors are highly homologous to bacterial rRNA dimethyltransferases, which suggests that an RNA-modifying enzyme has been recruited during evolution to function as a mitochondrial transcription factor. The presence of two proteins that interact with mammalian POLRMT may allow flexible regulation of mtDNA gene expression in response to the complex physiological demands of mammalian metabolism.

We studied the imprints that feedback from Active Galactic Nuclei (AGN) leaves on the intracluster plasma during the assembly history of galaxy clusters. To this purpose we used state-of-the-art cosmological hydrodynamical simulations based on an updated version of the Tree-PM SPH GADGET-3 code, comparing three sets of simulations with different prescriptions for the physics of baryons (including AGN and/or stellar feedback). We explore the effect of these different physics, in particular AGN feedback, on IntraCluster medium (ICM) properties observed via Sunyaev-Zel’dovich (SZ) effect using an extended set of galaxy clusters (~100 clusters with M 500 masses above 5 × 1013 M ⊙/h). Some of the main findings are that the scaling relation between the integrated SZ flux and the galaxy cluster total mass is in good accordance with several observed samples, especially for massive clusters, and does not show any clear redshift evolution, with the slope of the relation close to the theoretical one in the AGN feedback case. As for the scatter of this relation, we obtain a mild dependence on the cluster dynamical state.