Miracle-dz/UniFAR-FTUs huggingface dataset:
2MASS J154043.42 510135.7: a new addition to the 5 pc population

Aims. The aim of the project is to find the stars closest to the Sun and to contribute to the completion of the stellar and substellar census of the solar neighbourhood. Methods. We identified a new late-M dwarf within 5 pc, looking for high proper motion sources in the 2MASS–WISE cross-match. We collected astrometric and photometric data available from public large-scale surveys. We complemented this information with lowresolution (R ∼ 500) optical (600–1000 nm) and near-infrared (900–2500 nm) spectroscopy with instrumentation on the European Southern Observatory New Technology Telescope to confirm the nature of our candidate. We also present a high-quality mediumresolution VLT/X-shooter spectrum covering the 400 to 2500 nm wavelength range. Results. We classify this new neighbour as an M7.0 ± 0.5 dwarf using spectral templates from the Sloan Digital Sky Survey and spectral indices. Lithium absorption at 670.8 nm is not detected in the X-shooter spectrum, indicating that the M7 dwarf is older than 600 Myr and more massive than 0.06 M� . We also derive a trigonometric distance of 4.4 +0.5 −0.4 pc, in agreement with the spectroscopic distance estimate, making 2MASS J154043.42−510135.7 (2M1540) the nearest M7 dwarf to the Sun. This trigonometric distance is somewhat closer than the ∼6 pc distance reported by the ALLWISE team, who independently identified this object recently. This discovery represents an increase by 25% in the number of M7–M8 dwarfs already known at distances closer than 8 pc from our Sun. We derive a density of ρ = 1.9 ± 0.9 × 10 −3 pc −3 for M7 dwarfs in the 8 pc volume, a value similar to those quoted in the literature. Conclusions. This new ultracool dwarf is among the 50 closest systems to the Sun, demonstrating that our current knowledge of the stellar census within the 5 pc sample remains incomplete. 2M1540 represents a unique opportunity to search for extrasolar planets around ultracool dwarfs due to its proximity and brightness.
IDENTIFICATION OF z ≳ 2 Herschel 500 μm SOURCES USING COLOR DECONFUSION

We present a new method to search for candidate z ≳ 2 Herschel 500 μm sources in the Great Observatories Origins Deep Survey-North field using a S500 μm/S24 μm “color deconfusion” technique. Potential high-z sources are selected against low-redshift ones from their large 500 to 24 μm flux density ratios. By effectively reducing the contribution from low-redshift populations to the observed 500 μm emission, we are able to identify counterparts to high-z 500 μm sources whose 24 μm fluxes are relatively faint. The recovery of known z ≳ 4 starbursts confirms the efficiency of this approach in selecting high-z Herschel sources. The resulting sample consists of 34 dusty star-forming galaxies at z ≳ 2. The inferred infrared luminosities are in the range 1.5 × 1012–1.8 × 1013 L⊙, corresponding to dust-obscured star formation rates (SFRs) of ∼260–3100 M⊙ yr−1 for a Salpeter initial mass function. Comparison with previous SCUBA 850 &mgr; m ? > -selected galaxy samples shows that our method is more efficient at selecting high-z dusty galaxies, with a median redshift of z = 3.07 ± 0.83 ? > and with 10 of the sources at z ≳ 4. We find that at a fixed luminosity, the dust temperature is ∼5 K cooler than that expected from the T d − L IR ? > relation at z ≲ ? > 1, though different temperature selection effects should be taken into account. The radio-detected subsample (excluding three strong active galactic nucleus) follows the far-infrared (far-IR)/radio correlation at lower redshifts, and no evolution with redshift is observed out to z ∼ 5 ? > , suggesting that the far-IR emission is star formation dominated. The contribution of the high-z Herschel 500 μm sources to the cosmic SFR density is comparable to that of (sub)millimeter galaxy populations at z ∼ 2.5 ? > and at least 40% of the extinction-corrected UV samples at z ∼ 4 ? > . Further investigation into the nature of these high-z dusty galaxies will be crucial for our understanding of the star formation histories and the buildup of stellar mass at the earliest cosmic epochs.
Local modification of the Abrams-Lloyd nonlinear algorithm

The nonlinear algorithms proposed recently by Abrams and Lloyd [Report No. quant-ph/9801041] are fast but make an explicit use of an arbitrarily fast unphysical transfer of information within a quantum computer. It is shown that there exists a simplification of the second Abrams-Lloyd algorithm which eliminates the unphysical effect but keeps the algorithm fast.
Optimal Disturbance Rejection and Robustness for Infinite Dimensional LTV Systems

In this paper, we consider the optimal disturbance rejection problem for possibly infinite dimensional linear time-varying (LTV) systems using a framework based on operator algebras of classes of bounded linear operators. This approach does not assume any state space representation and views LTV systems as causal operators. After reducing the problem to a shortest distance minimization in a space of bounded linear operators, duality theory is applied to show existence of optimal solutions, which satisfy a "time-varying" allpass or flatness condition. Under mild assumptions the optimal TV controller is shown to be essentially unique. Next, the concept of M-ideals of operators is used to show that the computation of time-varying (TV) controllers reduces to a search over compact TV Youla parameters. This involves the norm of a TV compact Hankel operator defined on the space of causal trace-class 2 operators and its maximal vectors. Moreover, an operator identity to compute the optimal TV Youla parameter is provided. These results are generalized to the mixed sensitivity problem for TV systems as well, where it is shown that the optimum is equal to the operator induced of a TV mixed Hankel-Toeplitz. The final outcome of the approach developed here is that it leads to two tractable finite dimensional convex optimizations producing estimates to the optimum within desired tolerances, and a method to compute optimal time-varying controllers.
Non-asymptotic Error Bounds for Sequential MCMC Methods in Multimodal Settings

We prove non-asymptotic error bounds for Sequential MCMC methods in the case of multimodal target distributions. Our bounds depend in an explicit way on upper bounds on relative densities, on constants associated with local mixing properties of the MCMC dynamics, namely, local spectral gaps and local hyperboundedness, and on the amount of probability mass shifted between effectively disconnected components of the state space.
Upscaling pore‐scale reactive transport equations using a multiscale continuum formulation

Reactive transport equations are solved at the pore scale using the lattice Boltzmann (LB) method, and the results are upscaled using volume averaging over a representative elemental volume and are fit to a multiscale continuum model. The multiscale continuum model accounts for local concentration gradients within diffusion‐dominated matrix domains that are coupled to the primary continuum fluid. In general it is found that a multiscale continuum formulation is required to fit the upscaled pore‐scale results. However, it is also demonstrated that in some cases, multiscale processes may be represented by a single‐continuum model employing effective parameters that are not directly measurable. Provided that sufficient resolution of the pore‐scale geometry can be obtained, the pore‐scale model can be used to determine the most appropriate form of continuum formulation (single, dual, or multiple continua) that best fits the upscaled pore‐scale simulation and, simultaneously, to provide parameters needed for constitutive relations appearing in the multiscale continuum formulation. It is suggested that a multiscale continuum approach may help explain the observed discrepancy between laboratory and field‐derived reaction rates by explicitly representing distinct transport domains through separate interacting continua which could be responsible for the formation of preferential pathways. An example is presented on the basis of a multiscale, synthetic, structured porous medium describing transport of a tracer and linear reaction kinetics.
Threshold Pivoting for Dense LU Factorization

LU factorization is a key approach for solving large, dense systems of linear equations. Partial row pivoting is commonly used to ensure numerical stability; however, the data movement needed for the row interchanges can reduce performance. To improve this, we propose using threshold pivoting to find pivots almost as good as those selected by partial pivoting but that result in less data movement. Our theoretical analysis bounds the element growth similarly to partial pivoting; however, it also shows that the growth of threshold pivoting for a given matrix cannot be bounded by that of partial pivoting and vice versa. Additionally, we experimentally tested the approach on the Summit supercomputer. Threshold pivoting improved performance by up to 32% without a significant effect on accuracy. For a more aggressive configuration with up to one digit of accuracy lost, the improvement was as high as 44%.
Atf3 defines a population of pulmonary endothelial cells essential for lung regeneration

Following acute injury, the capillary vascular bed in the lung must be repaired to reestablish gas exchange with the external environment. Little is known about the transcriptional and signaling factors that drive pulmonary endothelial cell (EC) proliferation and subsequent regeneration of pulmonary capillaries, as well as their response to stress. Here, we show that the transcription factor Atf3 is essential for the regenerative response of the mouse pulmonary endothelium after influenza infection. Atf3 expression defines a subpopulation of capillary ECs enriched in genes involved in endothelial development, differentiation, and migration. During lung alveolar regeneration, this EC population expands and increases expression of genes involved in angiogenesis, blood vessel development, and cellular response to stress. Importantly, endothelial cell-specific loss of Atf3 results in defective alveolar regeneration, in part through increased apoptosis and decreased proliferation in the endothelium. This leads to the general loss of alveolar endothelium and persistent morphological changes to the alveolar niche, including an emphysema-like phenotype with enlarged alveolar airspaces lined with regions that lack vascular investment. Taken together, these data implicate Atf3 as an essential component of the vascular response to acute lung injury that is required for successful lung alveolar regeneration.
Chemical modification of human decellularized extracellular matrix for incorporation into phototunable hybrid-hydrogel models of tissue fibrosis

Tissue fibrosis remains a serious health condition with high morbidity and mortality rates. There is a critical need to engineer model systems that better recapitulate the spatial and temporal changes in the fibrotic extracellular microenvironment and enable study of the cellular and molecular alterations that occur during pathogenesis. Here, we present a process for chemically modifying human decellularized extracellular matrix (dECM) and incorporating it into a dynamically tunable hybrid-hydrogel system containing a poly(ethylene glycol)-alpha methacrylate (PEGαMA) backbone. Following modification and characterization, an off-stoichiometry thiol-ene Michael addition reaction resulted in hybrid-hydrogels with mechanical properties that could be tuned to recapitulate many healthy tissue types. Next, photoinitiated, free-radical homopolymerization of excess α-methacrylates increased crosslinking density and hybrid-hydrogel elastic modulus to mimic a fibrotic microenvironment. The incorporation of dECM into the PEGαMAhydrogel decreased the elastic modulus and, relative to fully synthetic hydrogels, increased the swelling ratio, the average molecular weight between crosslinks, and the mesh size of hybrid-hydrogel networks. These changes were proportional to the amount of dECM incorporated into the network. Dynamic stiffening increased the elastic modulus and decreased the swelling ratio, average molecular weight between crosslinks, and the mesh size of hybrid-hydrogels, as expected. Stiffening also activated human fibroblasts, as measured by increases in average cellular aspect ratio (1.59 ± 0.02 to 2.98 ± 0.20) and expression of α-smooth muscle actin (αSMA). Fibroblasts expressing αSMA increased from 24.4% to 51.8% upon dynamic stiffening, demonstrating that hybrid-hydrogels containing human dECM support investigation of dynamic mechanosensing. These results improve our understanding of the biomolecular networks formed within hybrid-hydrogels: this fully human phototunable hybrid-hydrogel system will enable researchers to control and decouple the biochemical changes that occur during fibrotic pathogenesis from the resulting increases in stiffness to study the dynamic cell-matrix interactions that perpetuate fibrotic diseases.
Maternal omega-3 fatty acid deficiency affects fetal thermogenic development and postnatal musculoskeletal growth in mice

Maternal omega-3 (n-3) polyunsaturated fatty acids (PUFAs) deficiency can affect offspring’s adiposity and metabolism by modulating lipid and glucose metabolism. However, the impact of n-3 PUFA deficiency on the development of fetal thermogenesis and its consequences is not reported. Using an n-3 PUFA deficient mice, we assessed fetal interscapular brown adipose tissue (iBAT), body fat composition, insulin growth factor-1 (IGF-1), glucose transporters (GLUTs), and expression of lipid storage & metabolic proteins in the offspring. The n-3 PUFA deficiency did not change the pups’ calorie intake, organ weight, and body weight. However, the offspring’s skeletal growth was altered due to excess fat to lean mass, reduced tibia & femur elongation, dysregulated IGF-1 in the mother and pups (p<0.05). Localization of uncoupling protein 1 (UCP1) in iBAT exhibited a reduced expression in the deficient fetus. Further, UCP1, GLUT1, GPR120 were downregulated while FABP3, ADRP, GLUT4 expressions were upregulated in the BAT of the deficient offspring (p<0.05). The deficiency decreased endogenous conversion of the n-3 LCPUFAs from their precursors and upregulated SCD1, FASN, and MFSD2A mRNAs in the liver (p<0.05). An altered musculoskeletal growth in the offspring is associated with impaired browning of the fetal adipose, dysregulated thermogenesis, growth hormone, and expression of glucose and fatty acid metabolic mediators due to maternal n-3 PUFA deficiency. BAT had higher metabolic sensitivity compared to WAT in n-3 PUFA deficiency. Maternal n-3 PUFA intake may prevent excess adiposity by modulating fetal development of thermogenesis and skeletal growth dynamics in the mice offspring. Highlight Maternal n-3 PUFA deficiency dysregulated the development of fetal adipose browning N-3 PUFA regulates fetal thermogenic development by altering UCP1 expression BAT had higher metabolic sensitivity compared to WAT in n-3 PUFA deficiency Increased fat mass and IGF-1 played a role in promoting adiposity in n-3 PUFA deficiency
The tendon interfascicular basement membrane provides a vascular niche for CD146+ pericyte cell subpopulations

The interfascicular matrix (IFM) is critical to the mechanical adaptations and response to load in energy-storing tendons, such as the human Achilles and equine superficial digital flexor tendon (SDFT). We hypothesized that the IFM is a tendon progenitor cell niche housing an exclusive cell subpopulation. Immunolabelling of equine SDFT was used to identify the IFM niche, localising expression patterns of CD31 (endothelial cells), CD146 (IFM cells) and LAMA4 (IFM basement membrane marker). Magnetic-activated cell sorting was employed to isolate and compare in vitro properties of CD146+ and CD146- subpopulations. CD146 demarcated an exclusive interfascicular cell subpopulation that resides in proximity to a basal lamina which forms interconnected vascular networks. Isolated CD146+ cells exhibited limited mineralization (osteogenesis) and lipid production (adipogenesis). This study demonstrates that the IFM is a unique tendon cell niche, containing a vascular-rich network of basement membrane, CD31+ endothelial cells and CD146+ cell populations that are likely essential to tendon structure- and/or function. Interfascicular CD146+ subpopulations did not exhibit stem cell-like phenotypes and are more likely to represent a pericyte lineage. Previous work has shown that tendon CD146 cells migrate to sites of injury, therefore mobilisation of endogenous tendon IFM cell populations may promote intrinsic repair.
Resting-state functional connectivity predictors of subjective visual Gestalt experience

Subjective perceptual experience is influenced not only by bottom-up sensory information and experience-based top-down processes, but also by an individual’s current brain state. Specifically, a previous study found increased prestimulus insula and intraparietal sulcus (IPS) activity before participants perceived an illusory Gestalt (global) compared to the non-illusory (local) interpretation in a bistable stimulus. This study provided only a snapshot of the prestimulus brain state that favors an illusory interpretation. In the current study, we tested the hypothesis that the neural machinery that biases perception towards the illusory interpretation immediately before the stimulus onset, is also predictive of an individual’s general tendency to perceive it, which remains stable over time. We examined individual differences in task-free functional connectivity of insula and IPS and related it to differences in the individuals’ duration of the two interpretations. We found stronger connectivity of the IPS with areas of the default mode and visual networks to predict shorter local perceptual phases, i.e., a faster switch to an illusory percept, but no equivalent results for the insula. Our findings suggest a crucial role of an IPS interaction with nodes of key intrinsic networks in forming a perceptual tendency towards illusory Gestalt perception.
Distributed network flows generate localized category selectivity in human visual cortex

A central goal of neuroscience is to understand how function-relevant brain activations are generated. Here we test the hypothesis that function-relevant brain activations are generated primarily by distributed network flows. We focused on visual processing in human cortex, given the long-standing literature supporting the functional relevance of brain activations in visual cortex regions exhibiting visual category selectivity. We began by using fMRI data from N=352 human participants to identify category-specific responses in visual cortex for images of faces, places, body parts, and tools. We then systematically tested the hypothesis that distributed network flows can generate these localized visual category selective responses. This was accomplished using a recently developed approach for simulating – in a highly empirically constrained manner – the generation of task-evoked brain activations by modeling activity flowing over intrinsic brain connections. We next tested refinements to our hypothesis, focusing on how stimulus-driven network interactions initialized in V1 generate downstream visual category selectivity. We found evidence that network flows directly from V1 were sufficient for generating visual category selectivity, but that additional, globally distributed (whole-cortex) network flows increased category selectivity further. Using null network architectures we also found that each region’s unique intrinsic “connectivity fingerprint” was key to the generation of category selectivity. These results generalized across regions associated with all four visual categories tested (bodies, faces, places, and tools), and provide evidence that the human brain’s intrinsic network organization plays a prominent role in the generation of functionally relevant, localized responses. Author Summary A fundamental question in neuroscience has persisted for over a century: to what extent do distributed processes drive brain function? The existence of category-selective regions within visual cortex provides long-standing evidence supporting localized computations, wherein specialized functions (e.g., selective responsiveness to face images) are thought to be primarily generated by within-region processes. This account was recently updated to include category selectivity dispersed across visual cortex, in the absence of category-selective regions. Here we provide groundwork evidence demonstrating that locally-exhibited visual-category-selective responses can be accurately generated via distributed activity flowing over globally connected systems. These processes were simulated via empirically-based computational models initialized by stimulus-evoked activity patterns and empirical connectivity matching each category-selective region’s unique intrinsic functional connectivity fingerprint. Results demonstrate that activity flowing over the human brain’s distributed network architecture can account for the generation of category selectivity in visual cortex regions.
The Allosterically Modulated Free Fatty Acid Receptor 2 is Transactivated by an Increase in the Cytosolic Concentration of Calcium Ions

Allosterically modulated free fatty acid receptor 2 (FFA2R/GPR43) can be activated without the involvement of any orthosteric FFA2R agonist, by signals generated for example by P2Y2R, the G protein coupled receptor for ATP. An FFA2R specific positive allosteric modulator (PAM; Cmp58) was used to disclose the molecular mechanism by which signals generated by ATP/P2Y2R transactivates FFA2R. The P2Y2R induced signal that transactivates the allosterically modulated FFA2R was generated downstream of the Gαq containing G protein that couple to P2Y2R. A receptor induced rise in the cytosolic concentration of ionized calcium ([Ca2+]i) was hypothesized to be the receptor transactivation signal. The Gαq dependent transient rise in [Ca2+]i induced by the ATP activated P2Y2Rs was not affected by Cmp58. The hypothesis gained, however, support from the finding that the modulator transferred FFA2R to a Ca2+ sensitive state. The rise in [Ca2+]i induced by the Ca2+ specific ionophore ionomycin, activated the allosterically modulated FFA2R. The response induced by ionomycin was rapidly terminated and the FFA2Rs could then no longer be activated by the orthosteric FFA2R agonist propionate or be transactivated by the signal generated by the activated ATP receptor. The desensitized/non-responding state of FFA2R was, however, revoked by an earlier described cross-sensitizing/activating allosteric FFA2R modulator. The receptor transactivation of the allosterically modulated FFA2Rs, represent a unique regulatory receptor cross-talk mechanism by which the activity of a G protein coupled receptor is controlled by a signaling system operating from the cytosolic side of the plasma membrane. One-sentence summary A P2Y2 receptor signal generated downstream of a Gαq containing G protein transactivates the allosterically modulated FFA2 receptor