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We describe the development of Chempath : an open-source pathway analysis program for photochemical models. This algorithm can help understand the results of complex photochemical models by identifying the most important reaction chains (pathways) for the production and destruction of a species of interest in a reaction system. The algorithm can also quantify the contribution of the pathways to the production and destruction of a species. We demonstrate how to apply Chempath to a one-dimensional photochemical model, using an example of a reaction system for Earth's present-day atmosphere. We validate that Chempath can identify well-known chemical mechanisms for O3 production and destruction in this model, suggesting that this algorithm can be applied to understand photochemical models of less well-known atmospheres, like past and exoplanet atmospheres. [ABSTRACT FROM AUTHOR]

Excitation energy transfer (EET) is a key photoinduced process in biological chromophoric assemblies. Here we investigate the factors which can drive EET into efficient ultrafast sub-ps regimes. We demonstrate how a coherent transport of electronic population could facilitate this in water solvated NADH coenzyme and uncover the role of an intermediate dark charge-transfer state. High temporal resolution ultrafast optical spectroscopy gives a 54±11 fs time constant for the EET process. Nonadiabatic quantum dynamical simulations computed through the time-evolution of multidimensional wavepackets suggest that the population transfer is mediated by photoexcited molecular vibrations due to strong coupling between the electronic states. The polar aqueous solvent environment leads to the active participation of a dark charge transfer state, accelerating the vibronically coherent EET process in favorably stacked conformers and solvent cavities. Our work demonstrates how the interplay of structural and environmental factors leads to diverse pathways for the EET process in flexible heterodimers and provides general insights relevant for coherent EET processes in stacked multichromophoric aggregates like DNA strands. Excitation energy transfer is important for many photoinduced biological processes in systems with multiple chromophores. Here, the authors elucidate this process for the coenzyme NADH using ultrafast spectroscopy and quantum dynamics. [ABSTRACT FROM AUTHOR]

Ultra-lean hydrogen–air flames propagating in narrow gaps, under the influence of cold walls and high preferential diffusion, can form two distinct isolated structures. They exhibit either circular or double-cell shapes and propagate at different speeds, with the latter roughly doubling in size and traveling speed to the former. Hydrogen mass diffusivity, convective effects, and conductive heat losses are the physical mechanisms that explain the alterations in morphology and propagation speed. In previous experiments, Veiga-López et al. [Phys. Rev. Lett. 124, 174501 (2020)] found these clearly distinguished flame structures for different combinations of equivalence ratio, channel gap, and the effect of gravity on the dynamics of upward and downward propagating flames in a vertical chamber. Present observations in horizontal channels show the simultaneous appearance of these two stable structures, which arise under identical experimental conditions and conform the first evidence that multiplicity of stable solutions coexists in real devices. To explain the observations, we performed numerical simulations using the simplified model, which shows that symmetry-breaking details during the ignition transient explain the concurrent emergence of the two stable configurations. This discovery urges the need to implement additional engineering tools to account for the possibility of the formation and propagation of isolated flame kernels at different speeds in hydrogen-fueled systems. [ABSTRACT FROM AUTHOR]

In magnetized liner inertial fusion (MagLIF), a cylindrical liner filled with fusion fuel is imploded with the goal of producing a one-dimensional plasma column at thermonuclear conditions. However, structures attributed to three-dimensional effects are observed in self-emission x-ray images. Despite this, the impact of many experimental inputs on the column morphology has not been characterized. We demonstrate the use of a linear regression analysis to explore correlations between morphology and a wide variety of experimental inputs across 57 MagLIF experiments. Results indicate the possibility of several unexplored effects. For example, we demonstrate that increasing the initial magnetic field correlates with improved stability. Although intuitively expected, this has never been quantitatively assessed in integrated MagLIF experiments. We also demonstrate that azimuthal drive asymmetries resulting from the geometry of the "current return can" appear to measurably impact the morphology. In conjunction with several counterintuitive null results, we expect the observed correlations will encourage further experimental, theoretical, and simulation-based studies. Finally, we note that the method used in this work is general and may be applied to explore not only correlations between input conditions and morphology but also with other experimentally measured quantities. [ABSTRACT FROM AUTHOR]

To assess the effects of the eFisioTrack monitoring system on clinical variables in patients with prescribed physiotherapy for shoulder injuries, twenty-four adult patients with shoulder orthopaedic injuries who underwent physical therapy treatment in a hospital setting participated in the study (twelve in the experimental group and twelve as controls). Clinical outcome measures were shoulder function and pain (Constant–Murley Score and Disabilities of the Arm, Shoulder, and Hand or DASH score). Each variable was measured by a blinded physiotherapist at baseline and at one month follow-up. Patients performed the prescribed exercises either supervised by the physiotherapist (control group) or in a separate room without therapist supervision (experimental group). There were no statistically significant differences between groups before treatment or at follow-up for any outcomes (p ≥ 0.05). There was a statistically significant decrease (p ≤ 0.05) of at least 10 points in both groups for the DASH score at follow-up. Differences in the total score and subjective components of the Constant–Murley were also evidenced within groups. The use of the eFisioTrack system showed similar results in clinical measures compared to those performed under the direct supervision of the physiotherapist. This approach might be suitable for providing an effective shoulder exercise program at home. [ABSTRACT FROM AUTHOR]

Humans and their microbiota have coevolved a mutually beneficial relationship in which the human host provides a hospitable environment for the microorganisms and the microbiota provides many advantages for the host, including nutritional benefits and protection from pathogen infection.sup.1. Maintaining this relationship requires a careful immune balance to contain commensal microorganisms within the lumen while limiting inflammatory anti-commensal responses.sup.1,2. Antigen-specific recognition of intestinal microorganisms by T cells has previously been described.sup.3,4. Although the local environment shapes the differentiation of effector cells.sup.3-5 it is unclear how microbiota-specific T cells are educated in the thymus. Here we show that intestinal colonization in early life leads to the trafficking of microbial antigens from the intestine to the thymus by intestinal dendritic cells, which then induce the expansion of microbiota-specific T cells. Once in the periphery, microbiota-specific T cells have pathogenic potential or can protect against related pathogens. In this way, the developing microbiota shapes and expands the thymic and peripheral T cell repertoire, allowing for enhanced recognition of intestinal microorganisms and pathogens. In young mice, antigens from the gut microbiota are trafficked by CX3CR1.sup.+ dendritic cells from the gut to the thymus, where they induce the expansion of T cells that are specific to commensal microorganisms., Author(s): Daniel F. Zegarra-Ruiz [sup.1] , Dasom V. Kim [sup.1] [sup.2] , Kendra Norwood [sup.3] , Myunghoo Kim [sup.3] [sup.12] , Wan-Jung H. Wu [sup.1] [sup.4] , Fatima B. Saldana-Morales [...]

To study the effect of plitidepsin antiviral treatment in immunocompromised COVID-19 patients with underlying haematological malignancies or solid tumours, particularly those who have undergone anti-CD20 therapies. We conducted a retrospective observational study, involving 54 adults treated with plitidepsin on compassionate use as an antiviral drug. Our analysis compared outcomes between patients with solid tumours and those with haematological malignancies, and a cohort of cases treated or not with anti-CD20 monoclonal antibodies. Patients with a history of anti-CD20 therapies showed a prolonged time-to-negative RT-PCR for SARS-CoV-2 infection compared to non-treated patients (33 d (28;75) vs 15 (11;25); p =.002). Similar results were observed in patients with solid tumours in comparison to those with haematological malignancies (13 (10;16) vs 26 (17;50); p <.001). No serious adverse events were documented. Patients with haematological malignancies appear to be at a heightened risk for delayed SARS-CoV-2 clearance and subsequent clinical complications. These findings support plitidepsin as a well-tolerated treatment in this high-risk group. A phase II clinical trial (NCT05705167) is ongoing to evaluate plitidepsin as an antiviral drug in this population. Haematological patients face an increased risk for severe COVID-19. Anti-CD20 therapies could increase fatal outcomes in COVID-19 patients. Persistent viral replication is increased in immunocompromised patients. Plitidepsin does not lead to new serious adverse events in immunocompromised patients. [ABSTRACT FROM AUTHOR]