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Author(s): D. Di Genova (corresponding author) [1, 2]; S. Kolzenburg [2]; S. Wiesmaier [2]; E. Dallanave [2]; D. R. Neuville [3]; K. U. Hess [2]; D. B. Dingwell [2] The [...]

Glass forms when a liquid is fast cooled preventing crystallization, across a reversible process known as the glass transition. Organic tissues are commonly preserved as glass by processes of vitrification at very low temperatures, known as cryopreservation, and can return to their original soft state when heated back to ambient temperature. It would therefore be impossible to find organic glass embedded in volcanic deposits that have reached several hundred of Celsius degrees. Here we demonstrate that material with glassy appearance found within the skull of a seemingly male human body entombed within the hot pyroclastic flow deposits of the 79 CE Vesuvius eruption formed by a unique process of vitrification of his brain at very high temperature, and is the only such occurrence on Earth. Calorimetric analyses show that the temperature at which the brain transformed into glass was well above 510 °C, implying that the body was exposed to the passage and vanishing of a short-lived, dilute and much hotter pyroclastic flow, explaining its early fast heating and the following very fast cooling. The glass that formed as a result of such a unique process attained a perfect state of preservation of the brain and its microstructures., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

The primary population of small ruminants in Spain is concentrated in the southern region, a critical area for the country's livestock production. Indirect economic losses can occur when this livestock is affected by gastrointestinal parasites. This study aimed to determine the prevalence of these parasites in small ruminant herds (159 sheep and 39 goats) through coprological analyses and conducted a survey on farmers' management practices related to gastrointestinal parasite control. The survey results revealed some important aspects: monitoring through coprological analyses is not a common practice; veterinarians are not typically involved in deworming plans; anthelmintic treatment in adults is often applied twice a year in sheep and once a year in goats; and finally, drug rotation was higher in sheep farms. Coprological analyses showed Eimeria spp. as the most common parasitic infection, followed by Strongyles infection. Other parasites like Moniezia spp., Trichuris spp., and D. dendriticum were less important, although their prevalence was higher in sheep than goats. This constitutes the first report on the epidemiological status of gastrointestinal parasites in small ruminants in southern Spain. Based on the survey findings, the introduction of certain management measures on farms could potentially mitigate parasite infections.

The majority of basaltic magmas stall in the Earth's crust as a result of the rheological evolution caused by crystallization during transport. However, the relationships between crystallinity, rheology and eruptibility remain uncertain because it is difficult to observe dynamic magma crystallization in real time. Here, we present in-situ 4D data for crystal growth kinetics and the textural evolution of pyroxene during crystallization of trachybasaltic magmas in high-temperature experiments under water-saturated conditions at crustal pressures. We observe dendritic growth of pyroxene on initially euhedral cores, and a surprisingly rapid increase in crystal fraction and aspect ratio at undercooling ≥30 °C. Rapid dendritic crystallization favours a rheological transition from Newtonian to non-Newtonian behaviour within minutes. We use a numerical model to quantify the impact of rapid dendritic crystallization on basaltic dike propagation, and demonstrate its dramatic effect on magma mobility and eruptibility. Our results provide insights into the processes that control whether intrusions lead to eruption or not., (© 2022. The Author(s).)

Bacterial leaf scorch (BLS), caused by Xylella fastidiosa ( Xf ), is a prevalent disease of blueberries in the southeastern United States. Initially, this disease was reported to be caused by X. fastidiosa subsp. multiplex ( Xfm ). However, a recent survey revealed the presence of another subspecies, X. fastidiosa subsp. fastidiosa ( Xff ), within naturally infected blueberry plantings in Georgia. Since knowledge regarding the origins of isolates causing Xf outbreaks can impact management recommendations, a routine method for identifying the pathogen at the subspecies level can be beneficial. Several detection strategies are available to identify Xf infection at the subspecies level. However, none of these have been developed for the routine and rapid differentiation of the blueberry-infecting Xf subspecies. Here, we developed two separate straightforward and rapid detection techniques, a cleaved amplified polymorphic sequence (CAPS) marker, and a loop-mediated isothermal amplification (LAMP) assay, targeting the RNA polymerase sigma-70 factor ( rpoD ) gene sequence of Xfm to discriminate between the two Xf subspecies infecting blueberry. With the CAPS marker, specific detection of Xfm isolates was possible from pure cultures, inoculated greenhouse-grown plant samples, and field infected blueberry samples by restriction digestion of the rpoD gene PCR product (amplified with primers RST31 and RST33) using the Bts I enzyme. The LAMP assay allowed for specific real-time amplification of a 204-bp portion of the Xfm rpoD gene from both pure bacterial cultures and infected plant material using the Genie ® III system, a result further affirmed by gel electrophoresis and SYBR™ Green I DNA staining for visual observation. These detection strategies have the potential to greatly aid existing diagnostic methods for determining the distribution and prevalence of these Xf subspecies causing bacterial leaf scorch (BLS) in blueberries in the southeastern United States.

Background: Social robots (SRs) have been used for improving anxiety in children in stressful clinical situations, such as during painful procedures. However, no studies have yet been performed to assess their effect in children while waiting for emergency room consultations., Objective: This study aims to assess the impact of SRs on managing stress in children waiting for an emergency room procedure through the assessment of salivary cortisol levels., Methods: This was an open randomized clinical trial in children attending a pediatric emergency department. Children accessing the emergency room were randomized to 1 of 3 groups: (1) playing with a NAO SR, (2) playing with a study nurse, or (3) waiting with parents. The salivary cortisol levels of all children were measured through a swab. Salivary cortisol levels before and after the intervention were compared in the 3 groups. We calculated the effect size of our interventions through the Cohen d-based effect size correlation (r)., Results: A total of 109 children aged 3-10 years were enrolled in the study, and 94 (86.2%) had complete data for the analyses. Salivary cortisol levels significantly decreased more in the group exposed to robot interaction than in the other two groups (r=0.75). Cortisol levels decreased more in girls (r=0.92) than in boys (r=0.57)., Conclusions: SRs are efficacious in decreasing stress in children accessing the emergency room and may be considered a tool for improving emotional perceptions of children and their families in such a critical setting., Trial Registration: ClinicalTrials.gov NCT04627909; https://clinicaltrials.gov/ct2/show/study/NCT04627909., (©Silvia Rossi, Silvano Junior Santini, Daniela Di Genova, Gianpaolo Maggi, Alberto Verrotti, Giovanni Farello, Roberta Romualdi, Anna Alisi, Alberto Eugenio Tozzi, Clara Balsano. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 13.01.2022.)

The numerical modelling of magma transport and volcanic eruptions requires accurate knowledge of the viscosity of magmatic liquids as a function of temperature and melt composition. However, there is growing evidence that volcanic melts can be prone to nanoscale modification and crystallization before and during viscosity measurements. This challenges the possibility of being able to quantify the crystal-free melt phase contribution to the measured viscosity. In an effort to establish an alternative route to derive the viscosity of volcanic melts based on the vibrational properties of their parental glasses, we have subjected volcanologically relevant anhydrous glasses to Brillouin and Raman spectroscopic analyses at ambient conditions. Here, we find that the ratio between bulk and shear moduli and the boson peak position embed the melt fragility. We show that these quantities allow an accurate estimation of volcanic melts at eruptive conditions, without the need for viscosity measurements. An extensive review of the literature data confirms that our result also holds for hydrous systems; this study thus provides fertile ground on which to develop new studies of the nanoscale dynamics of natural melts and its impact on the style of volcanic eruptions.

Xylella fastidiosa ( Xf ) is an emerging insect-vectored, xylem-limited bacterium that can cause disease on several economically important fruit and tree crops including almond, blueberry, citrus, grapevine, peach, and pecan. On blueberry, Xf causes bacterial leaf scorch (BLS), which is prevalent in the southeastern United States. This disease, previously reported to be caused by Xf subsp. multiplex ( Xfm ), can result in rapid plant decline and death of southern highbush (SHB) blueberry cultivars. In 2017, a survey of blueberry plantings in southern Georgia (U.S.A.) confirmed the presence of Xf -infected plants in eight of nine sites examined, and seven isolates were cultured from infected plants. Genetic characterization of these isolates through single-locus and multilocus sequence analysis revealed that three isolates from two sites belonged to Xf subsp. fastidiosa ( Xff ), with significant similarity to isolates from grapevine. After these three isolates were artificially inoculated onto greenhouse-grown SHB blueberries (cv. 'Rebel'), symptoms typical of BLS developed, and Xff infection was confirmed through genetic characterization and reisolation of the bacterium to fulfill Koch's postulates. Because all previously reported Xf isolates from blueberry have been characterized as Xfm , this is the first time that isolation of Xff has been reported from naturally infected blueberry plantings. The potential impact of Xff isolates on disease management in blueberry requires further exploration. Furthermore, given that isolates from both Xfm and Xff were obtained within a single naturally infected blueberry planting, blueberry in southern Georgia may provide opportunities for intersubspecific recombination between Xff and Xfm isolates.

Although gas exsolution is a major driving force behind explosive volcanic eruptions, viscosity is critical in controlling the escape of bubbles and switching between explosive and effusive behavior. Temperature and composition control melt viscosity, but crystallization above a critical volume (>30 volume %) can lock up the magma, triggering an explosion. Here, we present an alternative to this well-established paradigm by showing how an unexpectedly small volume of nano-sized crystals can cause a disproportionate increase in magma viscosity. Our in situ observations on a basaltic melt, rheological measurements in an analog system, and modeling demonstrate how just a few volume % of nanolites results in a marked increase in viscosity above the critical value needed for explosive fragmentation, even for a low-viscosity melt. Images of nanolites from low-viscosity explosive eruptions and an experimentally produced basaltic pumice show syn-eruptive growth, possibly nucleating a high bubble number density., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).)

Raman spectrometers will form a key component of the analytical suite of future planetary rovers intended to investigate geological processes on Mars. In order to expand the applicability of these spectrometers and use them as analytical tools for the investigation of silicate glasses, a database correlating Raman spectra to glass composition is crucial. Here we investigate the effect of the chemical composition of reduced silicate glasses on their Raman spectra. A range of compositions was generated in a diffusion experiment between two distinct, iron-rich end-members (a basalt and a peralkaline rhyolite), which are representative of the anticipated compositions of Martian rocks. Our results show that for silica-poor (depolymerized) compositions the band intensity increases dramatically in the regions between 550-780 cm -1 and 820-980 cm -1 . On the other hand, Raman spectra regions between 250-550 cm -1 and 1000-1250 cm -1 are well developed in silica-rich (highly polymerized) systems. Further, spectral intensity increases at ~965 cm -1 related to the high iron content of these glasses (~7-17 wt % of FeO tot ). Based on the acquired Raman spectra and an ideal mixing equation between the two end-members we present an empirical parameterization that enables the estimation of the chemical compositions of silicate glasses within this range. The model is validated using external samples for which chemical composition and Raman spectra were characterized independently. Applications of this model range from microanalysis of dry and hydrous silicate glasses (e.g., melt inclusions) to in situ field investigations and studies under extreme conditions such as extraterrestrial (i.e., Mars) and submarine volcanic environments.

The effect of chemical composition on the Raman spectra of a series of natural calcalkaline silicate glasses has been quantified by performing electron microprobe analyses and obtaining Raman spectra on glassy filaments (~450 µm) derived from a magma mingling experiment. The results provide a robust compositionally-dependent database for the Raman spectra of natural silicate glasses along the calcalkaline series. An empirical model based on both the acquired Raman spectra and an ideal mixing equation between calcalkaline basaltic and rhyolitic end-members is constructed enabling the estimation of the chemical composition and degree of polymerization of silicate glasses using Raman spectra. The model is relatively insensitive to acquisition conditions and has been validated using the MPI-DING geochemical standard glasses1 as well as further samples. The methods and model developed here offer several advantages compared with other analytical and spectroscopic methods such as infrared spectroscopy, X-ray fluorescence spectroscopy, electron and ion microprobe analyses, inasmuch as Raman spectroscopy can be performed with a high spatial resolution (1 µm 2 ) without the need for any sample preparation as a nondestructive technique. This study represents an advance in efforts to provide the first database of Raman spectra for natural silicate glasses and yields a new approach for the treatment of Raman spectra, which allows us to extract approximate information about the chemical composition of natural silicate glasses using Raman spectroscopy. We anticipate its application in handheld in situ terrestrial field studies of silicate glasses under extreme conditions (e.g. extraterrestrial and submarine environments)., (© 2015 The Authors Journal of Raman Spectroscopy Published by John Wiley & Sons Ltd.)

The molecular mechanisms by which glioblastoma multiforme (GBM) refracts and becomes resistant to radiotherapy treatment remains largely unknown. This radioresistance is partly due to the presence of hypoxic regions, which are frequently found in GBM tumors. We investigated the radiosensitizing effects of MEK/ERK inhibition on GBM cell lines under hypoxic conditions. Four human GBM cell lines, T98G, U87MG, U138MG and U251MG were treated with the MEK/ERK inhibitor U0126, the HIF-1α inhibitor FM19G11 or γ-irradiation either alone or in combination under hypoxic conditions. Immunoblot analysis of specific proteins was performed in order to define their anti‑oncogenic or radiosensitizing roles in the different experimental conditions. MEK/ERK inhibition by U0126 reverted the transformed phenotype and significantly enhanced the radiosensitivity of T98G, U87MG, U138MG cells but not of the U251MG cell line under hypoxic conditions. U0126 and ERK silencing by siRNA reduced the levels of DNA protein kinase catalytic subunit (DNA-PKcs), Ku70 and K80 proteins and clearly reduced HIF-1α activity and protein expression. Furthermore, DNA-PKcs siRNA-mediated silencing counteracted HIF-1α activity and downregulated protein expression suggesting that ERKs, DNA-PKcs and HIF-1α cooperate in radioprotection of GBM cells. Of note, HIF-1α inhibition under hypoxic conditions drastically radiosensitized all cell lines used. MEK/ERK signal transduction pathway, through the sustained expression of DNA-PKcs, positively regulates HIF-1α protein expression and activity, preserving GBM radioresistance in hypoxic condition.

Purpose: Chronic radiation cystitis (CRC) is a serious complication that can arise in patients with pelvic malignancies treated with radiotherapy. Polydeoxyribonucleotides (PDRNs) are known to reduce inflammation and improve tissue perfusion and angiogenesis. In this manuscript, we describe our observational experience regarding intravesical instillation of PDRNs in improving symptoms of CRC in subjects unresponsiveness to conventional medical therapy., Methods: Eight patients with persistent and/or worsening CRC symptoms, despite conventional therapy, received biweekly intravesical instillation of PDRNs for two consecutive months. Symptoms were scored according to the Late Effects of Normal Tissues-Subjective, Objective, Management, Analytic (LENT-SOMA) scale, before, at the end, and after 4 months following the PDRNs treatment., Results: Four months after instillations, a significant improvement in the subjective perception of CRC symptoms was experienced by participants. The mean LENT-SOMA score was reduced from 1.16+0.26 before to 0.34+0.035 after 4 months from instillations (p<0.001). No adverse effect related to instillations was reported., Conclusions: Subjective perception of persistent and/or worsening CRC symptoms, despite conventional therapy, is improved after intravesical instillation with PDRNs without adverse events. Even though we deduced suggestive insights, the results need to be collected and verified from a large-scale study.