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The accretion/ejection processes in T Tauri stars are fundamental to their physical evolution, while also impacting the properties and evolution of the circumstellar material at a time when planet formation takes place. To date, the characterization of ongoing accretion processes in stellar pairs at 5–50 au scales has been challenging as high-angular resolution spectrographs are required to extract the spectral features of each component. We present the analysis of spectroscopic observations of the tight (160 mas, 25 au) T Tauri system HT Lup A/B, obtained with MUSE at the Very Large Telescope in 2021 March and July. We focus on constraining the accretion/ejection processes and variability of the secondary component HT Lup B by searching for accretion tracers by applying high-resolution spectral differential imaging techniques. We retrieve strong (signal-to-noise ratio > 5) H α, H β, and [O i ] λ 6300 emission in both epochs. The H α and H β line fluxes showcase high variability, with variations up to 200%–300% between epochs. The fluxes are consistent with accretion rates of 3× 10−9 M ⊙ yr−1 and 8 × 10−10 M ⊙ yr−1 for the first and second epochs, respectively. We attribute the increased accretion activity during the first night to a "burst-like" event, followed by a relaxation period more representative of the common accretion activity of the system. The [O i ] λ 6300 line profiles remain relatively similar between epochs and suggest ejection rates on the order of 10−9−10−10 M ⊙ yr−1, compatible with moderate disk wind emission. Our results also indicate that the accretion processes of HT Lup B are compatible with Classical T Tauri stars, unlike previous classifications. [ABSTRACT FROM AUTHOR]

Context. Relativistic jets in active galactic nuclei are known for their exceptional energy output, and imaging the synthetic synchrotron emission of numerical jet simulations is essential for a comparison with observed jet polarization emission. Aims. Through the use of 3D hybrid fluid-particle jet simulations (with the PLUTO code), we overcome some of the commonly made assumptions in relativistic magnetohydrodynamic (RMHD) simulations by using non-thermal particle attributes to account for the resulting synchrotron radiation. Polarized radiative transfer and ray-tracing (via the RADMC-3D code) highlight the differences in total intensity maps when (i) the jet is simulated purely with the RMHD approach, (ii) a jet tracer is considered in the RMHD approach, and (iii) a hybrid fluid-particle approach is used. The resulting emission maps were compared to the example of the radio galaxy Centaurus A. Methods. We applied the Lagrangian particle module implemented in the latest version of the PLUTO code. This new module contains a state-of-the-art algorithm for modeling diffusive shock acceleration and for accounting for radiative losses in RMHD jet simulations. The module implements the physical postulates missing in RMHD jet simulations by accounting for a cooled ambient medium and strengthening the central jet emission. Results. We find a distinction between the innermost structure of the jet and the back-flowing material by mimicking the radio emission of the Seyfert II radio galaxy Centaurus A when considering an edge-brightened jet with an underlying purely toroidal magnetic field. We demonstrate the necessity of synchrotron cooling as well as the improvements gained when directly accounting for non-thermal synchrotron radiation via non-thermal particles. [ABSTRACT FROM AUTHOR]

Introduction: Autosomal recessive osteopetrosis (ARO) is a rare genetic disease, characterized by increased bone density due to defective osteoclast function. Most of the cases are due to TCIRG1 gene mutation, leading to severe bone phenotype and death in the first years of life. The standard therapy is the hematopoietic stem cell transplantation (HSCT), but its success is limited by several constraints. Conversely, gene therapy (GT) could minimize the immune-mediated complications of allogeneic HSCT and offer a prompt treatment to these patients. Methods: The Tcirgl-defective oc/oc mouse model displays a short lifespan and high bone density, closely mirroring the human condition. In this work, we exploited the oc/oc neonate mice to optimize the critical steps for a successful therapy. Results: First, we showed that lentiviral vector GT can revert the osteopetrotic bone phenotype, allowing long-term survival and reducing extramedullary haematopoiesis. Then, we demonstrated that plerixafor-induced mobilization can further increase the high number of HSPCs circulating in peripheral blood, facilitating the collection of adequate numbers of cells for therapeutic purposes. Finally, pre-transplant non-genotoxic conditioning allowed the stable engraftment of HSPCs, albeit at lower level than conventional total body irradiation, and led to long-term survival and correction of bone phenotype, in the absence of acute toxicity. Conclusion: These results will pave the way to the implementation of an effective GT protocol, reducing the transplant-related complication risks in the very young and severely affected ARO patients. [ABSTRACT FROM AUTHOR]

This article investigates how the IMF WEO growth forecast revisions behave across different horizons and country groups. Our main findings suggest that (i) growth revisions in horizons closer to the actual are generally larger, more volatile, and more negative; (ii) on average, growth revisions are in the right direction, becoming progressively more responsive to forecast errors as horizons get closer to the actual year; (iii) growth revisions in systemic economies are relevant for growth revisions in all country groups; (iv) across vintages, revisions for a given time horizon are not autocorrelated; within vintages, they tend to be positively associated, suggesting a persistent perception of short‐term shocks; and (v) professional growth revisions are highly correlated. [ABSTRACT FROM AUTHOR]

The radial structure of debris discs can encode important information about their dynamical and collisional history. In this paper, we present a three-phase analytical model to analyse the collisional evolution of solids in debris discs, focusing on their joint radial and temporal dependence. Consistent with previous models, we find that as the largest planetesimals reach collisional equilibrium in the inner regions, the surface density of dust and solids becomes proportional to ∼ r 2 within a certain critical radius. We present simple equations to estimate the critical radius and surface density of dust as a function of the maximum planetesimal size and initial surface density in solids (and vice versa). We apply this model to Atacama Large Millimeter/submillimeter Array observations of seven wide debris discs. We use both parametric and non-parametric modelling to test if their inner edges are shallow and consistent with collisional evolution. We find that four out of seven have inner edges consistent with collisional evolution. Three of these would require small maximum planetesimal sizes below 10 km, with HR 8799's disc potentially lacking solids larger than a few centimetres. The remaining systems have inner edges that are much sharper, which requires maximum planetesimal sizes ≳ 10 km. Their sharp inner edges suggest they could have been truncated by planets, which JWST could detect. In the context of our model, we find that the seven discs require surface densities below a Minimum Mass Solar Nebula, avoiding the so-called disc mass problem. Finally, during the modelling of HD 107146 we discover that its wide gap is split into two narrower ones, which could be due to two low-mass planets formed within the disc. [ABSTRACT FROM AUTHOR]

This paper explores the macroeconomic impact of social unrest, using a novel index based on news reports. It shows that unrest has an adverse effect on economic activity, with GDP remaining on average 0.2 percent below the pre-unrest baseline six quarters after a one-standard deviation increase in the unrest index. Moreover, results are robust to instrumenting via regional unrest to address potential endogeneity concerns. Unrest "events", captured by a large change in the unrest index, result in a more pronounced decline in GDP—a 1 percent reduction six quarters after the event—but impacts differ by type of event. The adverse impact of unrest on activity is mainly associated with sharp contractions in manufacturing and services, and consumption. However, it can be mitigated by strong institutions and by a country's policy space (such as fiscal space and exchange rate flexibility). [ABSTRACT FROM AUTHOR]

Dysregulation of the interleukin-1 (IL-1) pathway leads to immune diseases that can result in chronic tissue and organ inflammation. Although IL-1 blockade has shown promise in ameliorating these symptoms and improving patients' quality of life, there is an urgent need for more effective, long-lasting treatments. We developed a lentivirus (LV)–mediated gene transfer strategy using transplanted autologous hematopoietic stem/progenitor cells (HSPCs) as a source of IL-1 receptor antagonist (IL-1RA) for systemic delivery to tissues and organs. Transplantation of mouse and human HSPCs transduced with an IL-1RA–encoding LV ensured stable IL-1RA production while maintaining the clonogenic and differentiation capacities of HSPCs in vivo. We examined the efficacy of cell-mediated IL-1RA delivery in three models of IL-1–dependent inflammation, for which treatment hindered neutrophil recruitment in an inducible model of gout, prevented systemic and multi-tissue inflammation in a genetic model of cryopyrin-associated periodic syndromes, and reduced disease severity in an experimental autoimmune encephalomyelitis model of multiple sclerosis. Our findings demonstrate HSPC-mediated IL-1RA delivery as a potential therapeutic modality that can be exploited to suppress tissue and organ inflammation in diverse immune-related diseases involving IL-1–driven inflammation. Editor's summary: The IL-1 pathway is essential to fighting infection, but its dysregulation is associated with chronic inflammation in several autoinflammatory disorders. Colantuoni et al. developed a lentivirus (LV)–mediated gene transfer strategy with autologous hematopoietic stem/progenitor cells (HSPCs) that can be transplanted for systemic delivery of IL-1 receptor antagonist (IL-1RA). Mice transplanted with these LV-transduced HSPCs demonstrated ectopic expression of IL-1RA that was sufficient to prevent systemic and localized IL-1–mediated inflammation in murine models of neutrophil-mediated inflammation, cryopyrin-associated periodic syndrome, and experimental autoimmune encephalitis. This HSPC-based IL-1RA delivery method has the potential to be a viable alternative to current treatment options. —Christiana Fogg [ABSTRACT FROM AUTHOR]

Mobilized peripheral blood is increasingly used instead of bone marrow as a source of autologous hematopoietic stem/progenitor cells for ex vivo gene therapy. Here, we present an unplanned exploratory analysis evaluating the hematopoietic reconstitution kinetics, engraftment and clonality in 13 pediatric Wiskott-Aldrich syndrome patients treated with autologous lentiviral-vector transduced hematopoietic stem/progenitor cells derived from mobilized peripheral blood (n = 7), bone marrow (n = 5) or the combination of the two sources (n = 1). 8 out of 13 gene therapy patients were enrolled in an open-label, non-randomized, phase 1/2 clinical study (NCT01515462) and the remaining 5 patients were treated under expanded access programs. Although mobilized peripheral blood- and bone marrow- hematopoietic stem/progenitor cells display similar capability of being gene-corrected, maintaining the engineered grafts up to 3 years after gene therapy, mobilized peripheral blood-gene therapy group shows faster neutrophil and platelet recovery, higher number of engrafted clones and increased gene correction in the myeloid lineage which correlate with higher amount of primitive and myeloid progenitors contained in hematopoietic stem/progenitor cells derived from mobilized peripheral blood. In vitro differentiation and transplantation studies in mice confirm that primitive hematopoietic stem/progenitor cells from both sources have comparable engraftment and multilineage differentiation potential. Altogether, our analyses reveal that the differential behavior after gene therapy of hematopoietic stem/progenitor cells derived from either bone marrow or mobilized peripheral blood is mainly due to the distinct cell composition rather than functional differences of the infused cell products, providing new frames of references for clinical interpretation of hematopoietic stem/progenitor cell transplantation outcome. Scala et al. show that mobilized peripheral blood hematopoietic stem/progenitor cells are more enriched in repopulating stem cells than bone marrow. Moreover, the quantity and type of infused subsets correlated with gene therapy outcome in humans. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) stands out as sustainable feedstock for developing a circular carbon economy whose energy supply could be obtained by boosting the production of clean hydrogen from renewable electricity. H2‐dependent CO2 gas fermentation using acetogenic microorganisms offers a viable solution of increasingly demonstrated value. While gas fermentation advances to achieve commercial process scalability, which is currently limited to a few products such as acetate and ethanol, it is worth taking the best of the current state‐of‐the‐art technology by its integration within innovative bioconversion schemes. This review presents multiple scenarios where gas fermentation by acetogens integrate into double‐stage biotechnological production processes that use CO2 as sole carbon feedstock and H2 as energy carrier for products' synthesis. In the integration schemes here reviewed, the first stage can be biotic or abiotic while the second stage is biotic. When the first stage is biotic, acetogens act as a biological platform to generate chemical intermediates such as acetate, formate and ethanol that become substrates for a second fermentation stage. This approach holds the potential to enhance process titre/rate/yield metrics and products' spectrum. Alternatively, when the first stage is abiotic, the integrated two‐stage scheme foresees, in the first stage, the catalytic transformation of CO2 into C1 products that, in the second stage, can be metabolized by acetogens. This latter scheme leverages the metabolic flexibility of acetogens in efficient utilization of the products of CO2 abiotic hydrogenation, namely formate and methanol, to synthesize multicarbon compounds but also to act as flexible catalysts for hydrogen storage or production. [ABSTRACT FROM AUTHOR]

X-linked chronic granulomatous disease is a rare disease caused by mutations in the CYBB gene. While more extensive knowledge is available on genetics, pathogenesis, and possible therapeutic options, mitochondrial activity and its implications on patient monitoring are still not well-characterized. We have developed a novel protocol to study mitochondrial activity on whole blood of XCGD patients before and after transplantation, as well as on XCGD carriers. Here we present results of these analyses and of the restoration of mitochondrial activity in hyperinflamed X-linked Chronic Granulomatous Disease after hematopoietic stem cell transplantation. Moreover, we show a strong direct correlation between mitochondrial activity, chimerism, and DHR monitored before and after transplantation and in XCGD carriers. In conclusion, based on these findings, we suggest testing this new ready-to-use marker to better characterize patients before and after treatment and to investigate disease expression in carriers. [ABSTRACT FROM AUTHOR]

This brief presents a 12-bit successive approximation register (SAR)-based time-interleaved (TI) analog-to-digital converter (ADC) with a fully programmable interleaving factor. A total of six SAR sub-ADCs can be time-interleaved. The interleaving factor is programmable from 2 to 6, resulting in an overall sampling rate from 300 to 900MS/s. On-chip offset, gain, and timing skew background calibrations allow reducing the interleaving spurs to less than −73dBc in every configuration. In particular, the proposed difference-based skew calibration efficiently operates in any configuration, not being limited to power-of-2 interleaving factors. Fabricated in a 28-nm bulk CMOS process, the presented TI-ADC achieves a Nyquist-frequency signal-to-noise plus distortion ratio (SNDR) and a spurious-free dynamic range (SFDR) of 52.01dB and 58.82dBc at 900MS/s, respectively, with an active area occupation of 0.48 mm $^{\mathbf {2}}$ and similar metrics across all the configurations. Featuring a power dissipation of 42.96mW at 900MS/s, the Nyquist-frequency Schreier figure of merit (FoM) is 152.2dB, whereas the Walden one is 146.6fJ/Conv-step. [ABSTRACT FROM AUTHOR]

Does gross or net debt matter for long‐term sovereign spreads in emerging markets? The topic is important for understanding the borrowing cost implications of public asset–liability management decisions (e.g., using assets to lower debt). We investigate this question using data on emerging market economies (EMEs) over the period 1998–2014. We find that both gross debt and assets have a significant impact on long‐term sovereign bond spreads in emerging markets, with effects roughly offsetting each other (coefficients of opposite sign and similar magnitude). Hence, net debt seems more appropriate than gross debt when evaluating the impact of indebtedness on spreads. The empirical results suggest that an increase in net debt by 10 percentage points of GDP implies an increase in the spread by 100–120 basis points, and the effect is larger during periods of domestic distress. The key results from this empirical study are quite robust to alternative specifications and subgroups of EMEs. [ABSTRACT FROM AUTHOR]

The discovery of substructures in protoplanetary disks by the Atacama Large Millimeter/submillimeter Array (ALMA) has provided us with key insights into the formation of planets. However, observational constraints on the formation of rocky planets have been still sparse, especially because of the limited spatial resolution. The inner edge of the so-called dead zone is one of the preferential sites of rocky planet formation. We investigate the capabilities of ALMA and Next Generation Very Large Array (ngVLA) for observing a dust concentration expected at the inner edge of the dead zone around a Herbig star. Herbig Ae/Be stars are useful laboratories for exploring the evolution of rocky grains in protoplanetary disks because of their high luminosity that pushes the dead zone inner edge outward. We find that, thanks to its unprecedented angular resolution and sensitivity, ngVLA can detect the dust concentration at the dead zone inner edge, with a reasonable integration time of 10 hr at λ = 3, 7 mm, and 1 cm. The dust concentration is expected to be optically thick at the ALMA wavelengths and cannot be spatially resolved due to its limited resolution. On the other hand, the flux density from the inner disk regions (∼3â€"4 au) observed with current VLA is higher for disks with a dust ring, and hence would be a useful indicator that helps us choose potential candidates of disks having a dust concentration at the innermost region. With these observations we can characterize the process of dust concentration in the innermost disk regions, where rocky planets can form. [ABSTRACT FROM AUTHOR]

Gas fermentation by acetogens of the genus Clostridium is an attractive technology since it affords the production of biochemicals and biofuels from industrial waste gases while contributing to mitigate the carbon cycle alterations. The acetogenic model organisms C. ljungdahlii and C. autoethanogenum have already been used in large scale industrial fermentations. Among the natural products, ethanol production has already attained industrial scale. However, some acetogens are also natural producers of 2,3-butanediol (2,3-BDO), a platform chemical of relevant industrial interest. Here, we have developed a lab-scale screening campaign with the aim of enhancing 2,3-BDO production. Our study generated comparable data on growth and 2,3-BDO production of several batch gas fermentations using C. ljungdahlii and C. autoethanogenum grown on different gas substrates of primary applicative interest (CO2 · H2, CO · CO2, syngas) and on different media featuring different compositions as regards trace metals, mineral elements and vitamins. CO · CO2 fermentation was found to be preferable for the production of 2,3-BDO, and a fair comparison of the strains cultivated in comparable conditions revealed that C. ljungdahlii produced 3.43-fold higher titer of 2,3-BDO compared to C. autoethanogenum. Screening of different medium compositions revealed that mineral elements, Zinc and Iron exert a major positive influence on 2,3-BDO titer and productivity. Moreover, the CO2 influence on CO fermentation was explored by characterizing C. ljungdahlii response with respect to different gas ratios in the CO · CO2 gas mixtures. The screening strategies undertaken in this study led to the production of 2.03 ± 0.05 g/L of 2,3-BDO, which is unprecedented in serum bottle experiments. [ABSTRACT FROM AUTHOR]

In this article, we summarize our recent progress in observational studies of jet collimation in active galactic nuclei. We focus on the investigation of a relation between the properties of the collimation zone and the AGN accretion mode, recently proposed by Boccardi, B., Perucho, M., Casadio, C. et al., 2021, A&A, 647, A67. We also discuss the efforts made by our team to increase the still limited number of sources that can be imaged on sufficiently small spatial scales to probe such zone, and we present first results for new candidates. [ABSTRACT FROM AUTHOR]

High-angular resolution observations at submillimeter/millimeter wavelengths of disks surrounding young stars have shown that their morphology is made of azimuthally symmetric or point-symmetric substructures, in some cases with spiral arms or localized spur- or crescent-shaped features. The majority of theoretical studies with the aim of interpreting the observational results have focused on disk models with planets under the assumption that the disk substructures are due to diskâ€"planet interaction. However, so far, only in very few cases have exoplanets been detected in these systems. Furthermore, some substructures are expected to appear before planets form, as they are necessary to drive the concentration of small solids which can lead to the formation of planetesimals. In this work we present observational predictions from high-resolution 3D radiative hydrodynamical models that follow the evolution of gas and solids in a prototoplanetary disk. We focus on substructures in the distribution of millimeter-sized and smaller solid particles produced by the vertical shear instability. We show that their characteristics are compatible with some of the shallow gaps detected in recent observations at sub-mm/mm wavelengths and present predictions for future observations with better sensitivity and angular resolution with ALMA and a Next Generation Very Large Array. [ABSTRACT FROM AUTHOR]

Activating mutations in the BRAF-MAPK pathway have been reported in histiocytoses, hematological inflammatory neoplasms characterized by multi-organ dissemination of pro-inflammatory myeloid cells. Here, we generate a humanized mouse model of transplantation of human hematopoietic stem and progenitor cells (HSPCs) expressing the activated form of BRAF (BRAFV600E). All mice transplanted with BRAFV600E-expressing HSPCs succumb to bone marrow failure, displaying myeloid-restricted hematopoiesis and multi-organ dissemination of aberrant mononuclear phagocytes. At the basis of this aggressive phenotype, we uncover the engagement of a senescence program, characterized by DNA damage response activation and a senescence-associated secretory phenotype, which affects also non-mutated bystander cells. Mechanistically, we identify TNFα as a key determinant of paracrine senescence and myeloid-restricted hematopoiesis and show that its inhibition dampens inflammation, delays disease onset and rescues hematopoietic defects in bystander cells. Our work establishes that senescence in the human hematopoietic system links oncogene-activation to the systemic inflammation observed in histiocytic neoplasms. BRAF-MAPK activating mutations are reported in histiocytoses—hematological neoplasms with widespread pro-inflammatory myeloid cells. Here, the authors show that an activating mutant BRAF in haematopoietic stem and progenitor cells causes an oncogene-induced senescence response leading to myeloid restricted haematopoiesis, inflammation and histiocytosis. [ABSTRACT FROM AUTHOR]

We present a detailed analysis for a subset of the high-resolution (∼35 mas, or 5 au) ALMA observations from the Disk Substructures at High Angular Resolution Project (DSHARP) to search for faint 1.3 mm continuum emission associated with dusty circumplanetary material located within the narrow annuli of depleted emission (gaps) in circumstellar disks. This search used the Jennings et al. frank modeling methodology to mitigate contamination from the local disk emission and then deployed a suite of injection–recovery experiments to statistically characterize point-like circumplanetary disks in residual images. While there are a few putative candidates in this sample, they have only marginal local signal-to-noise ratios and would require deeper measurements to confirm. Associating a 50% recovery fraction with an upper limit, we find that these data are sensitive to circumplanetary disks with flux densities ≳50–70 μJy in most cases. There are a few examples where those limits are inflated (≳110 μJy) owing to lingering nonaxisymmetric structures in their host circumstellar disks, most notably for a newly identified faint spiral in the HD 143006 disk. For standard assumptions, this analysis suggests that these data should be sensitive to circumplanetary disks with dust masses. While those bounds are comparable to some theoretical expectations for young giant planets, we discuss how plausible system properties (e.g., relatively low host planet masses or the efficient radial drift of solids) could require much deeper observations to achieve robust detections. [ABSTRACT FROM AUTHOR]

We present high-resolution millimeter continuum and CO line observations for the circumbinary disk around V892 Tau to constrain the stellar and disk properties. The total mass of the two near-equal-mass A stars is estimated to be 6.0 ± 0.2 M⊙ based on our models of the Keplerian-dominated gas disk rotation. The detection of strong ionized gas emission associated with the two stars at 8 mm, when combined with previous astrometric measurements in the near-infrared, provides an updated view of the binary orbit with a = 7.1 ± 0.1 au, e = 0.27 ± 0.1, and P = 7.7 ± 0.2 yr, which is about half of a previously reported orbital period. The binary orbital plane is proposed to be nearly coplanar to the circumbinary disk plane (with a mutual inclination of only Δ = 8 ± 4.°2; another solution with Δ = 113° is less likely given the short realignment timescale). An asymmetric dust disk ring peaking at a radius of 0.″2 is detected at 1.3 mm and its fainter counterparts are also detected at the longer 8 and 9.8 mm. The CO gas disk, though dominated by Keplerian rotation, presents a mild inner and outer disk misalignment. The radial extension of the disk, its asymmetric dust ring, and the presence of a disk warp could all be explained by the interaction between the eccentric binary and the circumbinary disk, which we assume were formed with nonzero mutual inclination. Some tentatively detected gas spirals in the outer disk are likely produced by interactions with the low-mass tertiary component located 4″ to the northeast. Our analyses demonstrate the promising usage of V892 Tau as an excellent benchmark system to study the details of binary–disk interactions. [ABSTRACT FROM AUTHOR]

We present theoretical predictions for the free–free emission at centimeter wavelengths obtained from photoevaporation and magnetohydrodynamic (MHD) wind disk models adjusted to the case of the TW Hydrae young stellar object. For this system, disk photoevaporation with heating due to the high-energy photons from the star has been proposed as a possible mechanism to open the gap observed in the dust emission with the Atacama Large Millimeter/submillimeter Array. We show that the photoevaporation disk model predicts a radial profile for the free–free emission that is made of two main spatial components, one originated from the bound disk atmosphere at 0.5–1 au from the star, and another more extended component from the photoevaporative wind at larger disk radii. We also show that the stellar X-ray luminosity has a significant impact on both these components. The predicted radio emission from the MHD wind model has a smoother radial distribution which extends to closer distances to the star than the photoevaporation case. We also show that a future radio telescope such as the Next Generation Very Large Array would have enough sensitivity and angular resolution to spatially resolve the main structures predicted by these models. [ABSTRACT FROM AUTHOR]

We present simulations of the capabilities of the Atacama Large Millimeter/submillimeter Array (ALMA) and of a next-generation Very Large Array (ngVLA) to detect and resolve substructures due to terrestrial planets and super-Earths in nearby planet-forming disks. We adopt the results of global 2D hydrodynamical planet–disk simulations that account for the dynamics of gas and dust in a disk with an embedded planet. Our simulations follow the combined evolution of gas and dust for several thousand planetary orbits. We show that long integrations (several tens of hours) with the ngVLA can detect and spatially resolve dust structures due to low-mass rocky planets in the terrestrial planet formation regions of nearby disks (stellocentric radii r = 1–3 au), under the assumption that the disk viscosity in those regions is low (α ≤ 10−5). ALMA is instead unable to resolve these structures in these disk regions. We also show that high-resolution ngVLA observations separated by several days to a few weeks would allow us to detect the proper motion of the azimuthally asymmetric structures expected in the disk regions of terrestrial planet formation. [ABSTRACT FROM AUTHOR]

While protoplanetary disks often appear to be compact and well organized in millimeter continuum emission, CO spectral line observations are increasingly revealing complex behavior at large distances from the host star. We present deep Atacama Large Millimeter/submillimeter Array maps of the J = 2−1 transition of 12CO, 13CO, and C18O, as well as the J = 3−2 transition of DCO+, toward the T Tauri star RU Lup at a resolution of ∼0.3″ (∼50 au). The CO isotopologue emission traces four major components of the RU Lup system: a compact Keplerian disk with a radius of ∼120 au, a non-Keplerian "envelope-like" structure surrounding the disk and extending to ∼260 au from the star, at least five blueshifted spiral arms stretching up to 1000 au, and clumps outside the spiral arms located up to 1500 au in projection from RU Lup. We comment on potential explanations for RU Lup's peculiar gas morphology, including gravitational instability, accretion of material onto the disk, or perturbation by another star. RU Lup's extended non-Keplerian CO emission, elevated stellar accretion rate, and unusual photometric variability suggest that it could be a scaled-down Class II analog of the outbursting FU Ori systems. [ABSTRACT FROM AUTHOR]

The article employs the Latin colony of Fregellae as a case study to overcome the communis opinio that colonial settlements were parva simulacra Urbis (Gell. XVI.13.9). In particular, the colony, initially founded by Rome in the context of the Second Samnite War, could move away from the Urbs and develop localised interests. Such interests could be explained through a dynamic contact between colonists and local populations, thus forming a variegated social landscape which did not necessarily display cultural similarity with Rome. Similarly, the cityscape could be employed to ascertain how certain colonies chose architectural solutions which took into account localised needs. It is in this context that the article will examine the alliance between Fregellae and Rome in light of the Second Punic War. Traditionally interpreted as a demonstration of blind loyalty, the article will put forth the idea that the colony could decide its alliances in view of potential benefits, which, in the case of Fregellae, were manifested in the economic and military advantages reaped in the eastern Mediterranean. Interestingly, these benefits affected the colony and, more specifically, its architectural facade, as seen in the building activity carried out in the period immediately after the endeavours in the East. [ABSTRACT FROM AUTHOR]

The large crescents imaged by ALMA in transition discs suggest that azimuthal dust trapping concentrates the larger grains, but centimetre–wavelengths continuum observations are required to map the distribution of the largest observable grains. A previous detection at ∼1 cm of an unresolved clump along the outer ring of MWC 758 (Clump 1), and buried inside more extended sub-mm continuum, motivates followup VLA observations. Deep multiconfiguration integrations reveal the morphology of Clump 1 and additional cm-wave components that we characterize via comparison with a deconvolution of recent 342 GHz data (∼1 mm). Clump 1, which concentrates ∼1/3 of the whole disc flux density at ∼1 cm, is resolved as a narrow arc with a deprojected aspect ratio χ > 5.6, and with half the azimuthal width than at 342 GHz. The spectral trends in the morphology of Clump 1 are quantitatively consistent with the Lyra-Lin prescriptions for dust trapping in an anticyclonic vortex, provided with porous grains (f ∼ 0.2 ± 0.2) in a very elongated (χ ∼ 14 ± 3) and cold (⁠|$T\sim 23\pm 2\,$| K) vortex. The same prescriptions constrain the turbulence parameter α and the gas surface density Σg through |$\log _{10}\left(\alpha \times \Sigma _g / \mathrm{g\, cm}^{-2} \right) \sim -2.3\pm 0.4$|⁠, thus requiring values for Σg larger than a factor of a few compared to that reported in the literature from the CO isotopologues, if α ≲ 10−3. Such physical conditions imply an appreciably optically thick continuum even at cm-wavelengths (⁠|$\tau _{33\, \mathrm{GHz}}\sim 0.2$|⁠). A secondary and shallower peak at 342 GHz is about twice fainter relative to Clump 1 at 33 GHz. Clump 2 appears to be less efficient at trapping large grains. [ABSTRACT FROM AUTHOR]

This article explores the advantages that a semantic system could provide to the group of Hellenistic monumental sanctuaries in Latium. Initially conceived as expressions of local reactions against Rome or as local adoptions of Roman socio-cultural practices, a semantic model allows us to see (architectural) style as a communication tool in different contexts. In this setting, there is a shift from Hellenisation, as an acculturation pheomenon, to Hellenism, as a phenomenon of social expression. Thus, a semantic model also sheds light on modes of self-perception and how style was perceived by various audiences. In particular, Hellenistic sanctuaries should be examined from local, regional and pan-Mediterranean prespectives. The emphasis on contextual applications of the semantic model should also make us take into consideration diachronicity. Given that the phenomenon spanned two centuries (the second and first centuries BC), style and, its meaning and function(s) in society would have changed due to more intense building activity and the increased presence of Hellenistic architecture in Central Italy. This consideration further allows us to move away from a static acculturation approach and acquire a better understanding of cultural contact and ethnogenesis in both the ancient and contemporary worlds. [ABSTRACT FROM AUTHOR]

The polyhydroxyalkanoates (PHAs) are microbially-produced biopolymers that could potentially be used as sustainable alternatives to oil-derived plastics. However, PHAs are currently more expensive to produce than oil-derived plastics. Therefore, more efficient production processes would be desirable. Cell-free metabolic engineering strategies have already been used to optimize several biosynthetic pathways and we envisioned that cell-free strategies could be used for optimizing PHAs biosynthetic pathways. To this end, we developed several Escherichia coli cell-free systems for in vitro prototyping PHAs biosynthetic operons, and also for screening relevant metabolite recycling enzymes. Furthermore, we customized our cell-free reactions through the addition of whey permeate, an industrial waste that has been previously used to optimize in vivo PHAs production. We found that the inclusion of an optimal concentration of whey permeate enhanced relative cell-free GFPmut3b production by approximately 50%. In cell-free transcription-translation prototyping reactions, gas chromatography-mass spectrometry quantification of cell-free 3-hydroxybutyrate (3HB) production revealed differences between the activities of the Native DPhaC_C319A (1.18±0.39 μM), C104 DPhaC_C319A (4.62±1.31 μM) and C101 DPhaC_C319A (2.65±1.27 μM) phaCAB operons that were tested. Interestingly, the most active operon, C104 produced higher levels of PHAs (or PHAs monomers) than the Native phaCAB operon in both in vitro and in vivo assays. Coupled cell-free biotransformation/ transcription-translation reactions produced greater yields of 3HB (32.87±6.58 μM), and these reactions were also used to characterize a Clostridium propionicum Acetyl-CoA recycling enzyme. Together, these data demonstrate that cell-free approaches complement in vivo workflows for identifying additional strategies for optimizing PHAs production. [ABSTRACT FROM AUTHOR]

Human hematopoiesis is a complex and dynamic system where morphologically and functionally diverse mature cell types are generated and maintained throughout life by bone marrow (BM) Hematopoietic Stem/Progenitor Cells (HSPC). Congenital and acquired hematopoietic disorders are often diagnosed through the detection of aberrant frequency or composition of hematopoietic cell populations. We here describe a novel protocol, called 'Whole Blood Dissection' (WBD), capable of analyzing in a single test-tube, hematopoietic progenitors and all major mature cell lineages composing either BM or peripheral blood (PB) through a multiparametric flow-cytometry analysis. WBD allows unambiguously identifying in the same tube up to 23 different blood cell types including HSPC subtypes and all the major myeloid and lymphoid lineage compartments at different stages of maturation, through a combination of 17 surface and 1 viability cell markers. We assessed the efficacy of WBD by analyzing BM and PB samples from adult ( n = 8) and pediatric ( n = 9) healthy donors highlighting age-related shift in cell composition. We also tested the capability of WBD on detecting aberrant hematopoietic cell composition in clinical samples of patients with primary immunodeficiency or leukemia unveiling expected and novel hematopoietic unbalances. Overall, WBD allows unambiguously identifying >99% of the cell subpopulations composing a blood sample in a reproducible, standardized, cost-, and time-efficient manner. This tool has a wide range of potential pre-clinical and clinical applications going from the characterization of hematopoietic disorders to the monitoring of hematopoietic reconstitution in patients after transplant or gene therapy. © 2017 The Authors. Cytometry Part A Published by Wiley Periodicals, Inc. on behalf of ISAC. [ABSTRACT FROM AUTHOR]

Context. Large-scale vortices in protoplanetary disks are thought to form and survive for long periods of time. Hence, they can significantly change the global disk evolution and particularly the distribution of the solid particles embedded in the gas, possibly explaining asymmetries and dust concentrations recently observed at submillimeter and millimeter wavelengths. Aims. We investigate the spatial distribution of dust grains using a simple model of protoplanetary disk hosted by a giant gaseous vortex. We explore the dependence of the results on grain size and deduce possible consequences and predictions for observations of the dust thermal emission at submillimeter and millimeter wavelengths. Methods. Global 2D simulations with a bi-fluid code are used to follow the evolution of a single population of solid particles aerodynamically coupled to the gas. Possible observational signatures of the dust thermal emission are obtained using simulators of ALMA and Nest Generation Very Large Array (ngVLA) observations. Results. We find that a giant vortex not only captures dust grains with Stokes number St< 1 but can also affect the distribution of larger grains (with St ~ 1) carving a gap associated with a ring composed of incompletely trapped particles. The results are presented for different particle sizes and associated with their possible signatures in disk observations. Conclusions. Gap clearing in the dust spatial distribution could be due to the interaction with a giant gaseous vortex and their associated spiral waves without the gravitational assistance of a planet. Hence, strong dust concentrations at short sub-mm wavelengths associated with a gap and an irregular ring at longer mm and cm wavelengths could indicate the presence of an unseen gaseous vortex. [ABSTRACT FROM AUTHOR]

The accuracy in orientation tracking attainable by using inertial measurement units (IMU) when measuring human motion is still an open issue. This study presents a systematic quantification of the accuracy under static conditions and typical human dynamics, simulated by means of a robotic arm. Two sensor fusion algorithms, selected from the classes of the stochastic and complementary methods, are considered. The proposed protocol implements controlled and repeatable experimental conditions and validates accuracy for an extensive set of dynamic movements, that differ in frequency and amplitude of the movement. We found that dynamic performance of the tracking is only slightly dependent on the sensor fusion algorithm. Instead, it is dependent on the amplitude and frequency of the movement and a major contribution to the error derives from the orientation of the rotation axis w.r.t. the gravity vector. Absolute and relative errors upper bounds are found respectively in the range [0.7° ÷ 8.2°] and [1.0° ÷ 10.3°]. Alongside dynamic, static accuracy is thoroughly investigated, also with an emphasis on convergence behavior of the different algorithms. Reported results emphasize critical issues associated with the use of this technology and provide a baseline level of performance for the human motion related application. [ABSTRACT FROM AUTHOR]

This paper presents a new empirical regularity between the volatility of productivity growth and long-run unemployment for a given level of long-run productivity growth. A theoretical framework based on asymmetric real wage rigidities is shown to have the potential to rationalize this finding. The model tends to fit U.S. long-run unemployment better than a specification based on long-run productivity growth only, especially during the Great Moderation and the Great Recession. [ABSTRACT FROM AUTHOR]

The article focuses on a research on discovery of survival and activity of genetically modified T memory stem cells with in vivo tracking of T-cells. It mentions data from two gene therapy clinical trials for an inherited immunodeficiency, using either retrovirally engineered hematopoietic stem cells or mature lymphocytes. It concludes that T memory stem cells has ability to preserve their precursor potential in humans for up to 12 years after infusion of gene-corrected lymphocytes.

We are entering the era in which observations of protoplanetary disc's properties can indirectly probe the presence of massive planets or low-mass stellar companions interacting with the disc. In particular, the detection of warped discs can provide important clues to the properties of the star–disc system. In this paper, we show how observations of warped discs can be used to infer the dynamical properties of the systems. We concentrate on circumbinary discs, where the mass of the secondary can be planetary. First, we provide some simple relations that link the amplitude of the warp in the linear regime to the parameters of the system. Secondly, we apply our method to the case of TW Hya, a transition disc for which a warp has been proposed based on spectroscopic observations. Assuming values for the disc and stellar parameters from observations, we conclude that, in order for a warp induced by a planetary companion to be detectable, the planet mass should be large (Mp ≈ 10–14MJ) and the disc should be viscous (α ≈ 0.15–0.25). We also apply our model to LkCa 15 and T Cha, where a substellar companion has been detected within the central cavity of the transition discs. [ABSTRACT FROM PUBLISHER]

Action selection is extremely important, particularly when the accomplishment of competitive tasks may require access to limited motor resources. The spontaneous exploration of the world plays a fundamental role in the development of this capacity, providing subjects with an increasingly diverse set of opportunities to acquire, practice and refine the understanding of action-outcome connection. The computational modeling literature proposed a number of specific mechanisms for autonomous agents to discover and target interesting outcomes: intrinsic motivations hold a central importance among those mechanisms. Unfortunately, the study of the acquisition of action-outcome relation was mostly carried out with experiments involving extrinsic tasks, either based on rewards or on predefined task goals. This work presents a new experimental paradigm to study the effect of intrinsic motivation on action-outcome relation learning and action selection during free exploration of the world. Three- and four-year-old children were observed during the free exploration of a new toy: half of them were allowed to develop the knowledge concerning its functioning; the other half were not allowed to learn anything. The knowledge acquired during the free exploration of the toy was subsequently assessed and compared. [ABSTRACT FROM AUTHOR]

We recount the eight-year history of Vincenzo Rabito's original typescript between its consignment under the title Fontanazza to the Archivio Diaristico Nazionale (ADN) and its publication as Terra matta by Einaudi. In the first part, Ricci describes the selection process and award of the Premio Pieve and outlines the interventions in his edition which allowed for publication by either a specialist or a commercial publisher. In the second part, Santangelo illustrates how, working with both Rabito's original text and Ricci's edition, she brought a novelist's perspective to bear in bringing out the literary qualities required by the publisher. We indicate in detail our individual and joint working practices, the advice received from linguistic and other specialists, the choices with which we were confronted and the editorial strategies that produced the form and content of the published text. [ABSTRACT FROM AUTHOR]

Recent advances in wearable sensor technologies for motion capture have produced devices, mainly based on magneto and inertial measurement units (M-IMU), that are now suitable for out-of-the-lab use with children. In fact, the reduced size, weight and the wireless connectivity meet the requirement of minimum obtrusivity and give scientists the possibility to analyze children's motion in daily life contexts. Typical use of magneto and inertial measurement units (M-IMU) motion capture systems is based on attaching a sensing unit to each body segment of interest. The correct use of this setup requires a specific calibration methodology that allows mapping measurements from the sensors' frames of reference into useful kinematic information in the human limbs' frames of reference. The present work addresses this specific issue, presenting a calibration protocol to capture the kinematics of the upper limbs and thorax in typically developing (TD) children. The proposed method allows the construction, on each body segment, of a meaningful system of coordinates that are representative of real physiological motions and that are referred to as functional frames (FFs). We will also present a novel cost function for the Levenberg-Marquardt algorithm, to retrieve the rotation matrices between each sensor frame (SF) and the corresponding FF. Reported results on a group of 40 children suggest that the method is repeatable and reliable, opening the way to the extensive use of this technology for out-of-the-lab motion capture in children. [ABSTRACT FROM AUTHOR]

Nutritive Sucking (NS) is a highly organized process that is essential for infants' feeding during the first six months of their life. It requires the complex coordination of sucking, swallowing and breathing. The infant's inability to perform a safe and successful oral feeding can be an early detector of immaturity of the Central Nervous System (CNS). Even though the importance of early sucking measures has been confirmed over the years, the need for standardized instrumental assessment tools still exists. Clinicians would benefit from specifically designed devices to assess oral feeding ability in their routine clinical monitoring and decision-making process. This work is a review of the main instrumental solutions developed to assess an infant's NS behavior, with a detailed survey of the main quantities and indices measured and/or estimated to characterize sucking behavior skills and their development. The adopted sensing measuring systems will be described, and their main advantages and weaknesses will be discussed, taking into account their application to clinical practice, or to at-home monitoring as post-discharge assessment tools. Finally, the study will highlight the most suitable sensing solutions and give some prompts for further research. [ABSTRACT FROM AUTHOR]

This paper employs newly constructed measures for productivity differentials, external imbalances, and commodity terms of trade to estimate a panel cointegrating relationship between real exchange rates and a set of fundamentals for a sample of 48 industrial countries and emerging markets. It finds evidence of a strong positive relation between the consumer price index-based real exchange rate and commodity terms of trade. The estimated impact of productivity growth differentials between traded and nontraded goods, while statistically significant, is small. Increases in net foreign assets, government consumption, and trade restrictions tend to be associated with appreciating real exchange rates. [ABSTRACT FROM AUTHOR]

This paper uses a newly assembled multi-country multi-industry firm-level dataset to test the effect of productivity and networking on the export probability of firms. Results are in line with the new-new trade theory and with the literature on the information value of networks. Firms are more likely to export if they are more productive, larger, and if they benefit from foreign networks (ownership and financial linkages), domestic networks (chamber of commerce, links to regulation), and communication networks (E-mail, internet). Firms bear a lower probability of exporting if they are affected by state ownership or unionization networks. Overall, firms with better network connections by one standard deviation enjoy a 15% higher probability of exporting. [ABSTRACT FROM AUTHOR]

The macroeconomic implications of downward nominal wage rigidities are analyzed via a dynamic stochastic general equilibrium model featuring aggregate and idiosyncratic shocks. A closed-form solution for a long-run Phillips curve relates average output gap to average wage inflation: it is virtually vertical at high inflation and flattens at low inflation. Macroeconomic volatility shifts the curve outwards and reduces output. The results imply that stabilization policies play an important role, and that optimal inflation may be positive and differ across countries with different macroeconomic volatility. Results are robust to relaxing the wage constraint, for example, when large idiosyncratic shocks arise. (JEL E23, E24, E31, E63) [ABSTRACT FROM AUTHOR]

This paper estimates a small dynamic macroeconomic model for the South African economy with Bayesian methods. The model is tailored to assessing the impact of domestic as well as external shocks on inflation within an inflation-targeting framework, by incorporating forward-looking behavior of private agents and of the monetary authority. The model is able to display important empirical features of the monetary transmission mechanism that have been found in other studies. It helps to integrate the short-term inflation outlook into a consistent medium-term framework and to design the policy response for various shocks that affect inflation. [ABSTRACT FROM AUTHOR]

Do highly indebted countries suffer from a debt overhang? Can debt relief foster their growth rates? To answer these important questions, this article looks at how the debt-growth relation varies with indebtedness levels, as well as with the quality of policies and institutions, in a panel of developing countries. The main findings are that, in countries with good policies and institutions, there is evidence of debt overhang when the net present value of debt rises above 20–25 percent of GDP; however, debt becomes irrelevant above 70–80 percent. In countries with bad policies and institutions, thresholds appear to be lower, but the evidence of debt overhang is weaker and we cannot rule out that debt is always irrelevant. Indeed, in such countries, as well as in countries with high indebtedness levels, investment does not depend on debt levels. The analysis suggests that not all countries are likely to profit from debt relief, and thus that a one-size-fits-all debt relief approach might not be the most appropriate one. [ABSTRACT FROM AUTHOR]