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Macrophages are the main target cells for Mycobacterium tuberculosis (Mtb) infection. Previous studies have shown that Mtb actively upregulates phosphorus transport proteins, such as Rv0928 protein (also known as PstS3), to increase inorganic phosphate uptake and promote their survival under low phosphorus culture conditions in vitro. However, it is unclear whether this upregulation of PstS3 affects the intracellular survival of Mtb, as the latter is also largely dependent on the immune response of infected macrophages. By using Rv0928-overexpressing Mycobacterium smegmatis (Ms::Rv0928), we unexpectedly found that Rv0928 not only increased apoptosis, but also augmented the inflammatory response of infected macrophages. These enhanced cellular defense mechanisms ultimately led to a dramatic reduction in intracellular bacterial load. By investigating the underlying mechanisms, we found that Rv0928 interacted with the macrophage mitochondrial phosphate carrier protein SLC25A3, reduced mitochondrial membrane potential and caused mitochondrial cytochrome c release, which ultimately activated caspase-9-mediated intrinsic apoptosis. In addition, Rv0928 amplified macrophage mitochondrial ROS production, further enhancing proinflammatory cytokine production by promoting activation of NF-κB and MAPK pathways. Our study suggested that Mtb Rv0928 up-regulation enhanced the immune defense response of macrophages. These findings may help us to better understand the complex process of mutual adaptation and mutual regulation between Mtb and macrophages during infection. [ABSTRACT FROM AUTHOR]

Single-atom catalysts (SACs) have shown unexpected catalytic activity due to their unique electronic structure and coordination environment. Nonetheless, the synthesis of an atomically precise low-coordination single-atom catalyst remains a grand challenge. Herein, we report a coordinately unsaturated Ni-N3 single-atom electrocatalyst using a metal-organic framework (MOF) derived N-C support with abundant exposed N for excellent electrochemical CO2 reduction. The obtained Ni-N3/NC active site exhibited highly efficient CO2-to-CO conversion with a Faradaic efficiency of 94.6% at the current density of 100 mA/cm2. In situ X-ray absorption spectroscopy (XAS) measurement suggested that the Ni atomic center with unsaturated coordination had the lower initial chemical state and higher charge transfer ability. In situ Fourier transform infrared (FT-IR) and theoretical calculation results revealed that the unsaturated catalytically active center could facilitate activation of CO2 and thus heighten CO2 electroreduction activity. These findings provided insights into the rational design of definitive coordination structure of SACs for boosting activity and selectivity. [ABSTRACT FROM AUTHOR]

Copyright of Kirkuk University Journal for Scientific Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, we study the differential scattering cross-section (DSCS) in the first-order Born approximation. It is not difficult to show that the DSCS can be simplified in terms of the system response function. Also, the system response function has this property to be written in terms of the spectral function and the momentum distribution function in the impulse approximation (IA) scheme. Therefore, the DSCS in the IA scheme can be formulated in terms of the spectral function and the momentum distribution function. On the other hand, the DSCS for an electron off the 4 He and 1 6 O nuclei is calculated in the harmonic oscillator shell model. The obtained results are compared with the experimental data, too. The most important result derived from this study is that the calculated DSCS in terms of the spectral function has a high agreement with the experimental data at the low-energy transfer, while the obtained DSCS in terms of the momentum distribution function does not. Therefore, we conclude that the response of a many-fermion system to a probe particle in IA must be written in terms of the spectral function for getting accurate theoretical results in the field of collision. This is another important result of our study. [ABSTRACT FROM AUTHOR]

There has been a long-standing discrepancy between existing measurements of the total fusion cross section for the 17 O + 12 C system at E c. m. ∼ 14 MeV. In order to resolve this inconsistency, the cross section was measured in two overlapping energy ranges using an 17 O beam and the Encore active target detector at Florida State University. Encore is a self-normalizing detector that measures a large portion of the fusion excitation function with a single beam energy. It also provides full angular coverage of the measured evaporation residues, thus ensuring a model independent measurement of the total fusion cross section. The data reported here show an oscillatory structure not previously observed in this system and agree with all previously reported measurements, resolving the long-standing discrepancy. Coupled reaction channels calculations reproduce the data except in the region of the the oscillation, which matches a similar structure seen in the 16 O + 12 C total fusion excitation function. [ABSTRACT FROM AUTHOR]

The triaxial and hexadecapole deformations of the |$K^\pi=0^+$| and |$K^\pi=2^+$| bands of |$^{24}$| Mg have been investigated by the inelastic scatterings of various probes, including electrons, protons, and alpha(⁠|$\alpha$|⁠) particles, for a prolonged time. However, it has been challenging to explain the unique properties of the scatterings observed for the |$4^+_1$| state through reaction calculations. This paper investigates the structure and transition properties of the |$K^\pi=0^+$| and |$K^\pi=2^+$| bands of |$^{24}$| Mg employing the microscopic structure and reaction calculations via inelastic proton and |$\alpha$| scattering. In particular, the |$E4$| transitions to the |$4^+_1$| and |$4^+_2$| states are reexamined. The structure of |$^{24}$| Mg was calculated employing the variation after the parity and total angular momentum projections in the framework of the antisymmetrized molecular dynamics (AMD). The inelastic proton and |$\alpha$| reactions were calculated by the microscopic coupled-channel (MCC) approach by folding the Melbourne |$g$| -matrix |$NN$| interaction with the AMD densities of |$^{24}$| Mg. Reasonable results were obtained on the properties of the structure, including the energy spectra and |$E2$| and |$E4$| transitions of the |$K^\pi=0^+$| and |$K^\pi=2^+$| bands owing to the enhanced collectivity of triaxial deformation. The MCC+AMD calculation successfully reproduced the angular distributions of the |$4^+_1$| and |$4^+_2$| cross sections of proton scattering at incident energies of |$E_p=40$| –100 MeV and |$\alpha$| scattering at |$E_\alpha=100$| –400 MeV. This is the first microscopic calculation to describe the unique properties of the |$0^+_1\to 4^+_1$| transition. In the inelastic scattering to the |$4^+_1$| state, the dominant two-step process of the |$0^+_1\to 2^+_1\to 4^+_1$| transitions and the deconstructive interference in the weak one-step process were essential. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Physics is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: The field of allogeneic hematopoietic cell transplantation (allo‐HCT) began in the 1950s, and despite a seven decade history of remarkable clinical advances, graft‐versus‐host‐disease (GVHD) remains the greatest obstacle in its success due to considerable morbidity and mortality. Graft‐versus‐host disease is the second leading cause of transplantation‐related mortality (TRM) after relapse of primary disease. There are two main types of GVHD—acute and chronic—differing in the pathogenesis, time of onset, and clinical presentation. Objective: This review provides a comprehensive overview of chronic GVHD pathophysiology and current management paradigms, as well as consideration of promising novel therapies. Conclusion: Chronic GVHD is a serious disease which may be active for years, or even decades, requiring potentially years of immunosuppressive therapies and placing patients at risk for a number of late complications. While the oral cavity has long been recognized to be a prominent target of GVHD, and in particular, chronic GVHD, it must be recognized and appreciated that it is a complex systemic disease with a wide spectrum of clinical manifestations. [ABSTRACT FROM AUTHOR]

Fishing with an artificial light stimulus has existed for thousands of years. It started with simple techniques such as burning a large fire on the beach to attract fish, but over the centuries it has become increasingly technologically advanced. Today, the use of artificial light in commercial fishing plays a very important role in contributing to the total catch yield and economy of many industrialized fisheries. In most cases, fishing vessels employ lights at the surface, but more recently, low-powered LED lights installed directly on fishing gear have also become common. Using artificial light in commercial fishing applications appears to produce various outcomes and trade-offs (i.e., positive and negative effects). Positive benefits can include increases in catch rate, reductions in bycatch, and savings in energy, while negative effects can include ecological costs, overfishing, increased bycatch, production of plastic and marine litter, and greenhouse gas emission. This review provides an overview of fish vision in aquatic animals and the use of light in commercial industrialized fisheries, and provides discussion on potential solutions that strengthen the positive effects and minimize the negative effects of using artificial light in fishing applications. [ABSTRACT FROM AUTHOR]

The effect of the splitting of nuclear shells lying substantially lower than the Fermi energy on the fragmentation of multipole resonances in cross sections for the excitation of nuclei is studied by considering the example of M6 and E1 resonances in self-conjugate sd-shell nuclei. [ABSTRACT FROM AUTHOR]

Context. Superclusters of galaxies provide dynamical environments for the study of the formation and evolution of structures in the cosmic web from galaxies, to the richest galaxy clusters, and superclusters themselves. Aims. We study galaxy populations and search for possible merging substructures in the rich galaxy cluster A2142 in the collapsing core of the supercluster SCl A2142, which may give rise to radio and X-ray structures in the cluster, and affect galaxy properties of this cluster. Methods. We used normal mixture modelling to select substructure of the cluster A2142. We compared alignments of the cluster, its brightest galaxies (hereafter BCGs), subclusters, and supercluster axes. The projected phase space (PPS) diagram and clustercentric distributions are used to analyse the dynamics of the cluster and study the distribution of various galaxy populations in the cluster and subclusters. Results. We find several infalling galaxy groups and subclusters. The cluster, supercluster, BCGs, and one infalling subcluster are all aligned. Their orientation is correlated with the alignment of the radio and X-ray haloes of the cluster. Galaxy populations in the main cluster and in the outskirts subclusters are different. Galaxies in the centre of the main cluster at the clustercentric distances 0.5 h−1 Mpc (Dc/Rvir < 0.5, Rvir = 0.9 h−1 Mpc) have older stellar populations (with the median age of 10−11 Gyr) than galaxies at larger clustercentric distances. Star-forming and recently quenched galaxies are located mostly at the clustercentric distances Dc ≈ 1.8 h−1 Mpc, where subclusters fall into the cluster and the properties of galaxies change rapidly. In this region the median age of stellar populations of galaxies is about 2 Gyr. Galaxies in A2142 on average have higher stellar masses, lower star formation rates, and redder colours than galaxies in rich groups. The total mass in infalling groups and subclusters is M ≈ 6 × 1014 h −1M⊙, that is approximately half of the mass of the cluster. This mass is sufficient for the mass growth of the cluster from redshift z = 0.5 (half-mass epoch) to the present. Conclusions. Our analysis suggests that the cluster A2142 has formed as a result of past and present mergers and infallen groups, predominantly along the supercluster axis. Mergers cause complex radio and X-ray structure of the cluster and affect the properties of galaxies in the cluster, especially at the boundaries of the cluster in the infall region. Explaining the differences between galaxy populations, mass, and richness of A2142, and other groups and clusters may lead to better insight about the formation and evolution of rich galaxy clusters. [ABSTRACT FROM AUTHOR]

Inhibition of the mitochondrial permeability transition pore (MPTP) by the novel inhibitor GNX-4975 was characterized. Titration of MPTP activity in de-energized rat liver mitochondria allowed determination of the number of GNX-4975-binding sites and their dissociation constant (Ki). Binding sites increased in number when MPTP opening was activated by increasing [Ca2+ ], phenylarsine oxide (PAO) or KSCN, and decreased when MPTP opening was inhibited with bongkrekic acid (BKA) or ADP. Values ranged between 9 and 50 pmol/mg of mitochondrial protein, but the Ki remained unchanged at ~1.8 nM when the inhibitor was added before Ca2+ . However, when GNX-4975 was added after Ca2+ it was much less potent with a Ki of ~140 nM. These data imply that a protein conformational change is required to form the MPTP complex and generate the GNX-4975-binding site. Occupation of the latter with GNX-4975 prevents the Ca2+ binding that triggers pore opening. We also demonstrated that GNX-4975 stabilizes an interaction between the adenine nucleotide translocase (ANT), held in its 'c' conformation with carboxyatractyloside (CAT), and the phosphate carrier (PiC) bound to immobilized PAO. No components of the F1Fo-ATP synthase bound significantly to immobilized PAO. Our data are consistent with our previous proposal that the MPTP may form at an interface between the PiC and ANT (or other similar mitochondrial carrier proteins) when they adopt novel conformations induced by factors that sensitize the MPTP to [Ca2+ ]. We propose that GNX-4975 binds to this interface preventing a calcium-triggered event that opens the interface into a pore. [ABSTRACT FROM AUTHOR]

Mitochondrial permeability transition pore (mPTP) is a large channel located in the mitochondrial inner membrane. The opening ofmPTP during pathological calcium overload leads to the membrane depolarization and disruption of ATP production. mPTP activation has been implicated as a central event during the process of stress-induced cell death. mPTP is a supramolecular complex composed of many proteins. Recent studies suggest that mitochondrial ATPase plays the central role in the formation of mPTP. However, the structure of the central conducting pore part of mPTP (mPTPore) remains elusive. Here we review current models proposed for the mPTPore and involvement of polyP in its formation and regulation. We discuss the underestimated role of polyP as an effector and a putative structural component of the mPTPore. We propose the hypothesis that inclusion of polyP can explain such properties of mPTP activity as calcium activation, selectivity and voltage-dependence. [ABSTRACT FROM AUTHOR]

Context. Superclusters of galaxies can be used to test cosmological models of the formation and evolution of the largest structures in the cosmic web, and of galaxy and cluster evolution in superclusters. Aims. We study the distribution, masses, and dynamical properties of galaxy groups in the A2142 supercluster. Methods. We analyse the global luminosity density distribution in the supercluster and divide the supercluster into the high-density core and the low-density outskirts regions. We find galaxy groups and filaments in these regions, calculate their masses and mass-tolight ratios and analyse their dynamical state with 1D and 3D statistics. We use the spherical collapse model to study the dynamical state of the supercluster. Results. In the A2142 supercluster rich groups and clusters lie along an almost straight line forming the 50 h-1 Mpc long main body of the supercluster. The A2142 supercluster has a very high density core surrounded by lower-density outskirts. The total estimated mass of the supercluster is Mest = 6.2 ×1015Mo. More than a half of groups with at least ten member galaxies in the supercluster lie in the high-density core of the supercluster, centred at the X-ray cluster A2142. Most of the groups in the core region are multimodal. In the outskirts of the supercluster, the number of groups is larger than in the core, and groups are poorer. The orientation of the axis of the cluster A2142 follows the orientations of its X-ray substructures and radio halo, and is aligned along the supercluster axis. The high-density core of the supercluster with the global density D8 ≥ 17 and perhaps with D8 ≥ 13 may have started to collapse. Conclusions. A2142 supercluster with collapsing core and straight body, is an unusual object among superclusters. In the course of the future evolution, the supercluster may split into several systems. [ABSTRACT FROM AUTHOR]

Context. We present a spectrophotometric analysis of the galaxy population in the area of the merging cluster Abell 2384 at z = 0.094. Aims. We investigate the impact of the complex cluster environment on galaxy properties, such as colour, morphology, and star formation rate. Methods. We combined multi-object spectroscopy from the 2dF and EFOSC2 spectrographs with optical imaging of the inner 30 × 30 arcmin of A2384 taken with the ESO Wide Field Imager. We carried out a kinematical analysis using the EMMIX algorithm and biweight statistics. We address the possible presence of cluster substructures with the Dressler-Shectman test. Cluster galaxies are investigated with respect to [OII] and Hα equivalent width. Galaxies covered by our optical imaging observations are additionally analysed in terms of colour, star formation rate, and morphological descriptors, such as Gini coefficient and M20 index. We study cluster galaxy properties as a function of clustercentric distance and investigate the distribution of various galaxy types in colour-magnitude and physical space. Results. The Dressler-Shectman test reveals a substructure in the east of the 2dF field of view. We determine the mass ratio between the northern and southern subclusters to be ≲1.6:1. In accordance with other cluster studies, we find that a large number of the disk galaxies close to the cluster core show no detectable star formation (SF). Probably these are systems that are quenched by ram-pressure stripping. The sample of quenched disks populates the transition area between the blue cloud and the red sequence in colour-magnitude space. We also find a population of morphologically distorted galaxies in the central cluster region. Conclusions. The substructure east of A2384 might be a group of galaxies falling onto the main cluster. We speculate that our sample of quenched spirals represents an intermediate phase in the ram-pressure-driven transformation of infalling field spirals into cluster S0s. This is justified by their position in colour-magnitude space. The occurrence of morphologically distorted galaxies in the cluster core complies with the hypothesis of Abell 2384 representing a post merger system. [ABSTRACT FROM AUTHOR]

The random phase approximation (RPA) equations based on the generalized density matrix (GDM), the so-called GDRPA are reformulated in a more compact matrix form, which renders the method especially suitable for realistic nuclear structure calculations. The GDRPA Hamiltonian is expressed in terms of the one-body particle-particle ( pp) and hole-hole ( hh) density matrices, and the nuclear force contributes not only in the particle-hole ( ph) channel, as in normal ph-RPA, but also in the pp and hh channels. The Hamiltonian is diagonalized iteratively starting from initial guess values and the iterating process is carried out until self-consistency is achieved. The calculation in the model space 1p, 1d and 2s using Warburton and Brown interaction WBP is performed for 16O. The GDRPA in the ph shell model calculations is tested, by comparing the energy eigenvalues and the electron scattering form factors with the results of the normal RPA and with the available experimental data. [ABSTRACT FROM AUTHOR]

We present results from a study of 12 X-ray bright clusters at 1.4 GHz with the 100 m Green Bank Telescope. After subtraction of point sources using existing interferometer data, we reach a median (best) 1σ rms sensitivity level of 0.01 (0.006) μJy arcsec–2, and find a significant excess of diffuse, low surface brightness emission in 11 of 12 Abell clusters observed. We also present initial results at 1.4 GHz of A2319 from the Very Large Array. In particular, we find: (1) four new detections of diffuse structures tentatively classified as two halos (A2065, A2069) and two relics (A2067, A2073); (2) the first detection of the radio halo in A2061 at 1.4 GHz, which qualifies this as a possible ultra-steep spectrum halo source with a synchrotron spectral index of α ∼ 1.8 between 327 MHz and 1.4 GHz; (3) a ∼2 Mpc radio halo in the sloshing, minor-merger cluster A2142; (4) a >2× increase of the giant radio halo extent and luminosity in the merging cluster A2319; (5) a ∼7× increase to the integrated radio flux and >4× increase to the observed extent of the peripheral radio relic in A1367 to ∼600 kpc, which we also observe to be polarized on a similar scale; (6) significant excess emission of ambiguous nature in three clusters with embedded tailed radio galaxies (A119, A400, A3744). Our radio halo detections agree with the well-known X-ray/radio luminosity correlation, but they are larger and fainter than current radio power correlation studies would predict. The corresponding volume-averaged synchrotron emissivities are 1-2 orders of magnitude below the characteristic value found in previous studies. Some of the halo-like detections may be some type of previously unseen, low surface brightness radio halo or blend of unresolved shock structures and sub-Mpc-scale turbulent regions associated with their respective cluster merging activity. Four of the five tentative halos contain one or more X-ray cold fronts, suggesting a possible connection between gas sloshing and particle acceleration on large scales in some of these clusters. Additionally, we see evidence for a possible inter-cluster filament between A2061 and A2067. For our faintest detections, we note the possibility of residual contamination from faint radio galaxies not accounted for in our confusion subtraction procedure. We also quantify the sensitivity of the NVSS to extended emission as a function of size. [ABSTRACT FROM AUTHOR]

Context. We present a spectrophotometric analysis of the galaxy population in the area of the merging cluster Abell 3921 at z = 0.093. Aims. We investigate the impact of the complex cluster environment on galaxy properties such as morphology or star formation rate. Methods. We combine multi-object spectroscopy from the two-degree field (2dF) spectrograph with optical imaging taken with the ESO Wide Field Imager. We carried out a redshift analysis and determine cluster velocity dispersions using biweight statistics. Applying a Dressler-Shectman test we sought evidence of cluster substructure. Cluster and field galaxies were investigated with respect to [OII] and Hα equivalent width, star formation rate, and morphological descriptors, such as concentration index and Gini coefficient. We studied these cluster galaxy properties as a function of clustercentric distance and investigated the spatial distribution of various galaxy types. Results. Applying the Dressler-Shectman test, we find a third component (A3921-C) in addition to the two main subclusters (A3921-A and A3921-B) that are already known. The re-determined mass ratio between the main components A and B is ~2:1. Similar to previous studies of galaxy clusters, we find that a large fraction of the disk galaxies close to the cluster core show no detectable star formation. These are likely systems that are quenched due to ram pressure stripping. Interestingly, we also find quenched spirals at rather large distances of 3-4 Mpc from the cluster core. Conclusions. A3921-C might be a group of galaxies falling onto the main cluster components. We speculate that the unexpected population of quenched spirals at large clustercentric radii in A3921-A and A3921-B might be an effect of the ongoing cluster merger: shocks in the ICM might give rise to enhanced ram pressure stripping and at least in part be the cause for the quenching of star formation. These quenched spirals might be an intermediate stage in the morphological transformation of field spirals into cluster S0s. [ABSTRACT FROM AUTHOR]

The yields of photonucleon reactions on the isotope Ta that are induced by bremsstrahlung photons whose endpoint energy is 67.7 MeV are measured by the residual-activity method. The cross sections for photonucleon reactions on the isotope Ta are calculated on the basis of the TALYS code and a combined model. The measured reaction yields are compared with their counterparts rescaled from cross sections obtained in experiments that employed beams of quasimonochromatic and bremsstrahlung photons. The spectra of neutrons emitted from Ta nuclei after the absorption of photons having various energies are calculated within the TALYS code and the combined model in question. [ABSTRACT FROM AUTHOR]

No abstract received. [ABSTRACT FROM AUTHOR]

Copyright of Il Nuovo Cimento: A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)