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Background. The role of forensic pathologists is pivotal in definitively diagnosing drowning cases. Further differentiation becomes essential for distinguishing between freshwater drowning (FWD) and saltwater drowning (SWD). Aquaporins are small integral membrane proteins that serve as major water transport pathways in various cell types. AQP4 appears to be involved in mechanisms related to cerebral volume regulation. Our study aims to examine the expression of AQP4 in the brain as a potential marker for differentiating between FWD and SWD relating to autopsy-performing timing. Materials and Methods. A total of 23 cases were classified into three groups: FWD, SWD, and controls. All samples were classified upon autopsy-performing timing into two subgroups: within and after 72 hours of death. The samples were then processed for histological and immunohistochemical investigations. Conclusion. For autopsies performed within 72 hours of death, we found a significantly higher value of AQP4-positive astrocytes in cases of FWD compared to SWD and control groups. We also found a significantly lower AQP4 expression in SWD cases compared to the control group. For autopsies conducted after 72 hours, the immunohistochemical staining does not reveal the peripheral terminations of astrocytes, which appear blurred and only recognizable as halos. In conclusion, the data aligns with existing literature about autopsies performed within 72 hours. However, in autopsies conducted after 72 hours, uncertain and even opposed results are observed. The difference can be ascribed to the post-mortem transformative processes that take place upon the cessation of vital functions. [ABSTRACT FROM AUTHOR]

Background. Investigating deaths related to chronic cocaine abuse can be a difficult task, particularly when they occur suddenly and without explanation. Cocaine abuse can trigger biological effects similar to physiological stressors, causing the body to produce heatshock proteins (HSPs). However, there is still limited information on the specific levels of each HSP type. This systematic review aims to comprehensively collect and analyze all existing literature data regarding the relationship between HSPs and cocaine abuse to investigate whether HSPs can be utilized as forensic markers for accurately diagnosing cocaine-related deaths. Materials and Methods. The Authors conducted the literature search using PubMed and Scopus databases, searching for articles published between 1 January 1992 and 1 April 2024 using the text string: "heat shock protein" AND "cocaine". Conclusion. Twenty articles were collected, but only nine were included in the systematic review. The data gathered pertained to both human and murine species. The majority of the analyzed articles revealed an elevation in HSP25, HSP27, HSP60, HSP70, HSP72, and HSP73 levels in the brain, cerebellum, and liver, indicating cocaine-induced stress. The relationship between HSP and cocaine has been unclear over time. However, recent studies have shown that cocaine consumption leads to an increase in HSP levels, particularly in the central nervous system. This correlation can also be observed in certain types of liver cells that are capable of binding cocaine metabolites. In conclusion, HSP brain levels, along with other biomarkers, may be used to diagnose sudden, unexpected death related to cocaine abuse. [ABSTRACT FROM AUTHOR]

This paper aims to provide new insights on the origin of the TeV source VER J1907+062 through new high-quality radio observations. We used the Karl G. Jansky Very Large Array (VLA) to observe the whole extension of VER J1907+062 at 1.5 GHz with a mosaicking technique and the PSR J1907+0602 in a single pointing at 6 GHz. These data were used together with 12CO and atomic hydrogen observations obtained from public surveys to investigate the interstellar medium in the direction of VER J1907+062. The new radio observations do not show any evidence of a pulsar wind nebula (PWN) driven by the pulsars present in the field and no radio counterpart to the proposed X-ray PWN powered by PSR J1907+0602 is seen in the new VLA image at 6 GHz down to a noise level of 10  |$\mu$| Jy beam−1. Molecular clouds were discovered over the eastern, southern, and western borders of the radio shell of G40.5−0.5, suggesting an association with this supernova remnant. We explored several scenarios for the origin of VER J1907+062. We propose as the most probable scenario one in which the TeV emission is produced by two separated γ-ray sources located at different distances: one of leptonic origin and associated with a PWN powered by PSR J1907+0602 at ∼3.2 kpc and another of hadronic origin and produced by the interaction between G40.5−0.5 and the surrounding molecular gas at ∼8.7 kpc. [ABSTRACT FROM AUTHOR]

We performed three-dimensional magnetohydrodynamic simulations to study the evolution of a supernova remnant (SNR) in a turbulent neutral atomic interstellar medium. The media used as background shares characteristics with the Solar neighbourhood and the SNR has mass and energy similar to those of a Type Ia object. Our initial conditions consist of dense clouds in a diluted medium, with the main difference between simulations being the average magnitude of the magnetic field. We measured amplifications of the magnetic energy of up to 34  |${{\rm per\ cent}}$|⁠ , and we generated synthetic maps that illustrate how the same object can show different apparent geometries and physical properties when observed through different lines of sight. [ABSTRACT FROM AUTHOR]

Aims. The goal of this paper is to detect synchrotron emission from the relic electrons of the crushed pulsar wind nebula (PWN) HESS J1825−137 and to investigate the origin of the γ-ray emission from HESS J1826−130. Methods. The study of HESS J1825−137 was carried out on the basis of new radio observations centred at the position of PSR J1826−1334 performed with the Karl G. Jansky Very Large Array at 1.4 GHz in configurations B and C. To investigate the nature of HESS J1826−130, we reprocessed unpublished archival data obtained with XMM-Newton. Results. The new radio continuum image towards PSR J1826−1334 reveals a bright radio source, with the pulsar located in its centre, which suggests that this feature could be the radio counterpart of the compact component of the PWN detected at high energy. The new 1.4 GHz radio data do not reveal emission with an extension comparable with that observed in γ-rays for the HESS J1825−137 source. On the other hand, the XMM-Newton study of the region including PSR J1826−1256 reveals an elongated non-thermal X-ray emitting nebula with the pulsar located in the northern border and a tail towards the peak of the very high energy source. The spectrum is characterized by a power law with a photon index going from 1.6 around the pulsar to 2.7 in the borders of the nebula, a behaviour consistent with synchrotron cooling of electrons. From our X-ray analysis we propose that HESS J1826−130 is likely produced by the PWN powered by PSR J1826−1256 via the inverse Compton mechanism. [ABSTRACT FROM AUTHOR]

In this work, we have modelled the supernova remnant (SNR) G296.5+10, by means of 3D magnetohydrodynamics (MHD) simulations. This remnant belongs to the bilateral SNR group and has an additional striking feature: the rotation measure (RM) in its eastern and western parts are very different. In order to explain both the morphology observed in radio-continuum and the RM, we consider that the remnant expands into a medium shaped by the superposition of the magnetic field of the progenitor star with a constant Galactic magnetic field. We have also carried out a polarization study from our MHD results, obtaining synthetic maps of the linearly polarized intensity and the Stokes parameters. This study reveals that both the radio morphology and the reported RM for G296.5+10 can be explained if the quasi-parallel acceleration mechanism is taking place in the shock front of this remnant. [ABSTRACT FROM AUTHOR]

Aims. We report on the first detailed multiwavelength study of the radio source G29.37+0.1, which is an as-yet-unclassified object linked to the very-high-energy -emitting source HESS J1844-030. The origin of the multiwavelength emission toward G29.37+0.1 has not been clarified so far, leaving open the question about the physical relationship between these sources. Methods. Using observations carried out with the Giant Metrewave Radio Telescope (GMRT), we performed high-quality fullsynthesis imaging at 610 MHz of the field containing G29.37+0.1. The obtained data, combined with observations at 1400 MHz from The Multi-Array Galactic Plane Imaging Survey (MAGPIS) were used to investigate in detail the properties of its radio emission. Additionally, we reprocessed archival data obtained with the XMM-Newton and Chandra observatories in order to get a multiwavelength view of this unusual source. Results. The radio source G29.37+0.1 mainly consists of a bright twisted structure, named the S-shaped feature. The high sensitivity of the new GMRT observations allowed the identification of potential lobes, jets, and a nuclear central region in the S-shaped morphology of G29.37+0.1. We also highlight the detection of diffuse and low surface brightness emission enveloping the brightest emitting regions. The brightest emission in G29.37+0.1 has a radio synchrotron spectral index α = 0.59 ± 0.09. Variations in the spectral behaviour are observed across the whole radio source with the flattest spectral features in the central nuclear and jets components (α ~ 0:3). These results lead us to conclude that the brightest radio emission from G29.37+0.1 likely represents a newly recognized radio galaxy. The identification of optical and infrared counterparts to the emission arising from the core of G29.37+0.1 strengthens our interpretation of an extragalactic origin of the radio emission. We performed several tests to explain the physical mechanism responsible for the observed X-ray emission, which appears overlapping the northeastern part of the radio emission. Our spectral analysis demonstrated that a non-thermal origin for the X-ray emission compatible with a pulsar wind nebula is quite possible. The analysis of the spatial distribution of the CO gas revealed the presence of a complex of molecular clouds located in projection adjacent to the radio halo emission and probably interacting with it. We propose that the faint halo represents a composite supernova remnant with a pulsar powered component given by the diffuse X-ray emission superimposed along the line of sight to the radio galaxy. Further broadband observations of HESS J1844-030 are needed to disentangle its origin, although its shape and position suggest an extragalactic origin connected to G29.37+0.1. [ABSTRACT FROM AUTHOR]

We characterize an uncatalogued bright-rimmed cloud located at the border of the infrared dust bubble CN20 with the aim of investigating triggered star formation. In order to do this, we carried out radio continuum observations at 8.9 GHz using the Jansky Very Large Array (JVLA) interferometer with a synthesized beam size of 13 arcsec ? 5 arcsec, and molecular observations using the Atacama Submillimeter Telescope Experiment (ASTE) at the 13CO J = 3-2 and CS J = 7-6 transitions. An analysis of the molecular observations and of Herschel public data revealed the presence of a warm and dense clump with Tdust ~ 25 K and n(H2) ~ 3 ? 105 cm-3. The high angular resolution and sensitivity of the new radio continuum data revealed an arc-like radio filament in excellent correspondence with the illuminated border of the bright-rimmed cloud. This ionized boundary layer has an electron density of 176 cm-3. The spatial distribution of the young stellar object candidates probably related to the bright-rimmed cloud does not show clear evidence of a triggered origin. Finally, based on the evaluation of the pressure balance between the ionized and molecular gas, we conclude that the ionization front has stalled at the surface of the clump. [ABSTRACT FROM AUTHOR]

We introduce a distinct method for performing spatially resolved spectral analysis of astronomical sources with highly structured X-ray emission. The method measures the surface brightness of neighboring pixels to adaptively size and shape each region, thus the spectra from the bright and faint filamentary structures evident in the broadband images can be extracted. As a test case, we present the spectral analysis of the complete X-ray emitting plasma in the supernova remnant Puppis A observed with XMM-Newton and Chandra. Given the angular size of Puppis A, many pointings with different observational configurations have to be combined, presenting a challenge to any method of spatially resolved spectroscopy. From the fit of a plane-parallel shocked plasma model we find that temperature, absorption column, ionization time scale, emission measure, and elemental abundances of O, Ne, Mg, Si, S, and Fe, are smoothly distributed in the remnant. Some regions with overabundances of O, Ne, and Mg previously characterized as ejecta material, were automatically selected by our method, proving the excellent response of the technique. This method is an advantageous tool for the exploitation of archival X-ray data. [ABSTRACT FROM AUTHOR]

Aims. The luminous blue variable (LBV) stars are peculiar very massive stars. The study of these stellar objects and their surroundings is important for understanding the evolution of massive stars and its effects on the interstellar medium. We study the LBV star candidate G26.47+0.02. Methods. Using several large-scale surveys in different frequencies we performed a multiwavelength study of G26.47+0.02 and its surroundings. Results. We found a molecular shell (seen in the 13CO J = 1-0 line) that partially surrounds the mid-infrared nebula of G26.47+0.02, which suggests an interaction between the strong stellar winds and the molecular gas. From the HI absorption and the molecular gas study we conclude that G26.47+0.02 is located at a distance of ∼4.8 kpc. The radio continuum analysis shows both thermal and non-thermal emission toward this LBV candidate, pointing to wind-wind collision shocks from a binary system. This hypothesis is supported by a search of near-IR sources and the Chandra X-ray analysis. Additional multiwavelength and long-term observations are needed to detect some possible variable behavior, and if that is found, to confirm the binary nature of the system. [ABSTRACT FROM AUTHOR]

Aims. We study the molecular environment of the luminous blue variable star G24.73+0.69 to investigate the origin of the two infrared shells around this massive star and determine its effects on the surrounding interstellar medium. Methods. We analyze the distribution of the molecular gas using the 13CO J = 1-0 emission extracted from the Galactic Ring Survey. We use near- and mid-infrared data from 2MASS and GLIMPSE to identify the young stellar objects in the field. Results. We discover the molecular counterpart to the outer infrared shell around G24.73+0.69. The CO shell was probably blown by the stellar wind of the star mainly during its main sequence phase. We also find molecular gas that corresponds to the inner infrared shell, although its origin remains uncertain. We identify seven young stellar objects within the molecular material, whose birth might have been triggered by the stellar wind of the luminous blue variable star. We suggest that both G24.73+0.69 and the progenitor of the nearby supernova remnant G24.7+0.6 were formed from the same natal cloud and represent the most evolved members of a so far undetected cluster of massive stars. [ABSTRACT FROM AUTHOR]

ABSTRACT We present the results of a new study of the molecular gas associated with the 'extended green object' (EGO) G35.03+0.35. This object, very likely a massive young stellar object, is embedded in a molecular cloud at the border of an H ii region. The observations were performed with the Atacama Submillimeter Telescope Experiment in the 12CO and 13CO J= 3-2, HCO+ J= 4-3 and CS J= 7-6 lines with an angular resolution of about 22 arcsec. From the 12CO J= 3-2 line, we discovered outflowing activity of the massive young stellar object. We obtained a total mass and kinetic energy for the outflows of 30 and 3000 M⊙ (km s−1)2 (6 × 1046 erg), respectively. We discovered an HCO+ and CS clump towards the EGO G35.03+0.35. The detection of these molecular species supports the presence of molecular outflows and a dense molecular envelope with temperatures and densities above 40 K and 6 × 106 cm−3, respectively. Using public near- and mid-infrared and submillimetre data, we investigated the spectral energy distribution confirming that EGO G35.03+0.35 is a massive young stellar object at its earliest evolutionary stage (i.e. a class I young stellar object). By analysing radio-continuum archival data, we found three radio sources towards the object, suggesting the presence of several young stellar objects in the region. Our radio-continuum analysis is consistent with the presence of at least one ultracompact H ii region and a hypercompact H ii region or a constant-velocity ionized wind source. [ABSTRACT FROM AUTHOR]