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The crustal feeding systems of Toba caldera (Indonesia) remain largely unknown due to (1) the lack of seismic images resolving magmatic sills and fluid reservoirs and (2) our inability to translate seismic parameters into meaningful petrophysical quantities. Using data from available seismic arrays, we obtained thousands of dispersion curves sensitive to both the shallow crust and the upper mantle. The usual seismological approach is to invert them for phase-velocity maps at different periods and transform them into a shear-wave model. This model shows low-velocity sill-like structures at different depths under the northern and central Toba caldera; however, the uncertainty in their interpretation cannot be quantified just by looking at their shape, depths and correlation with surface features.Therefore, we used a Gibbs energy-minimization solver thatcomputes seismic velocities from phase petrology for the compositions relevant to Toba to forward phase velocities directly. A Bayesian Monte Carlo Markov chain inversion then inverts for temperature, composition, background host rock damageand melt content. As a result, every velocity value from our calculations is petrologically feasible. The results identify the portions of the crust where mafic sills are located, quantitatively defining their melt content, chemical composition, rock damage, temperature and associated uncertainty. Due to the low sensitivity of shear waves to temperature, there are still fundamental challenges in defining the thermal structure of the volcano; yet, seismo-petrological inversions are feasible today within one of the most complex crustal systems, a result few expected to achieve a decade ago.&nbsp, The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The Mt.Pollino area is the largest seismic gap in Italy, with faults capable of M6.5-7 but no historical and instrumental M6 events recorded. Between 2010 and 2014 this area has been affected by a seismic sequence of more than 10,000 small magnitude earthquakes and two moderate main events occurred late in the sequence (ML 4.3 and ML 5.0).The goal of this work is to provide 3D scattering and absorption images of this area using the peak delay time and the coda-Q methods, respectively. Scattering anomalies suggest that the area involved in the sequence is highly fractured, with the strongest scattering contrast interpreted as the Pollino Fault. This large structure acted as a barrier, bounding migration of the seismicity southward, as suggested in recent structural geological works. Declustered high-absorption anomalies mark the area affected by the sequence, suggesting that fluids have played a key role in its development. This result is in good agreement with high VP/VS and high pore pressure anomalies highlighted by recent works on the area.This work was supported by the PRIN-2017 MATISSE project (no. 20177EPPN2), funded by the Italian Ministry of Education and Research.

This is a case of a 32-year-old primigravid who developed sudden severe headache on the 7th day postpartum associated with focal neurologic deficits and altered sensorium. She had a GCS score of 6, anisocoric pupils and an NIHSS score of 31. Cranial MRI with MRA showed multifocal hyperacute to acute infarcts on the left occipital lobe, left thalamus, and midbrain which was more prominent on the right. Due to clinical deterioration, a repeat Cranial MRI with MRA was done and showed progression of infarcts involving both thalami and right pons with interval appearance of contour irregularities in the proximal anterior cerebral, posterior cerebral, basilar and internal carotid arteries. Serial transcranial Doppler showed significant distal right middle cerebral artery vasospasm. She was managed as a case of reversible cerebral vasoconstriction syndrome, associated with postpartum cerebral angiopathy. Intravenous pulse methylprednisolone was started subsequently IVIG was initiated. Intravenous immunoglobulin was given for 5 days. The patient gradually improved, underwent rehabilitation therapy, and was discharged stable after 6 weeks.

Understanding the magmatic plumbing system of rift volcanoes is essential when examining the interplay between magmatic and tectonic forces. Recent seismicity, volcanic activity, magma emplacement, and volatile release make the Natron basin the ideal location to study these processes in the East African Rift System. Here, we present the first high‐resolution tomographic imaging of Oldoinyo Lengai volcano and surrounding volcanic systems using attenuation mapping. High scattering and absorption features reveal fluid‐filled fracture networks below regions of magmatic volatile release at the surface and a close spatial association between carbonatite volcanism and deeply penetrating, fluid‐filled faults. High‐absorption features appear sensitive to fluids and thermal gradients, revealing a central sill complex and connected plumbing system down to the mid‐crust, which links volcanoes and rift segments across the developing magmatic rift., Plain Language Summary: The interplay between magmatic and tectonic forces during rifting is still debated. While they are a key component of rift development, the complex structures of rifts and melt storage systems scatter and absorb seismic waves passing through them: in turn, this deteriorates the quality of the subsurface images we obtain from them. In this study, we use the loss of energy suffered by seismic waves to image the Natron basin, which hosts extinct volcanoes and the only active natrocarbonatite volcano on Earth, Oldoinyo Lengai. The results identify areas of melt storage and fracture networks that feed volatiles and melt to this volcano. Results suggest that carbonatite melts may ascend through the crust efficiently along deep‐seated faults systems, while silicate melts in the region may be primarily sourced from a separate melt reservoir. This reservoir, which is elongate and oriented oblique to the general trend of the rift, may act as a magmatic transfer zone between two rift segments., Key Points: First fine‐scale 3D images reveal an interconnected rift plumbing system using scattering and absorption mapping. High scattering and absorption mark fluid‐filled faults that degas magmatic fluids and act as potential conduits for carbonatite melts. A high absorption melt reservoir feeds eruptions at Oldoinyo Lengai and dike intrusions and acts as a transfer zone between rift segments., Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, National Science Foundation http://dx.doi.org/10.13039/100000001, Terrestrial Magmatic Systems, https://github.com/LucaDeSiena/MuRAT, https://doi.org/10.14470/4W7564850022, http://doi.org/10.6084/m9.figshare.20101232

Purpose: This study examined attitudes, perceived control, perceived norms, intention, and policy support before and after the peak of E-cigarette or Vaping Product Use-Associated Lung Injury (EVALI) cases among 2 independent samples of U.S. adults. Design: This study used a successive independent samples design. Setting: Data was collected through online surveys in July 2019 (n = 521) and October 2019 (n = 536). Subjects: Participants were recruited through the Qualtrics Survey Panel. Eligibility criteria included: 1) 18 years or older, and 2) currently living in the U.S. Measures: The 2 surveys were collected from 2 separate samples examined e-cigarette attitudes, perceived control, perceived norms, intention, and policy support. Analysis: Linear regressions were used to examine the association between time, attitudinal, and belief factors associated with intention and policy support. Results: Participants in the October sample (n = 521) were significantly more likely to have negative attitudes towards e-cigarettes when compared to the July sample (n = 536), F(8,1047) = 52.671, p < .01, R2 = 0.287. Lower perceived social acceptance towards e-cigarettes and negative attitudes were related to higher support for restricting where e-cigarettes could be used, F(11, 1042) = 63.218, p < .010, R2 = .401. Higher perceived control over accessing e-cigarettes, but lower social acceptance of e-cigarettes and negative beliefs were associated with higher support for limiting places where e-cigarettes could be purchased, F(11,1039) = 36.200, p < .01, R2 = .277. Conclusion: Results indicate that EVALI cases may have had an immediate negative effect on attitudes but did not appear to decrease intention to use e-cigarettes. Results could inform future public health campaigns' programming and research. More research is needed to understand the long-term impact of EVALI on e-cigarette use.

Aposporous apomictic plants form clonal maternal seeds by inducing the emergence of non-reduced (2n) embryo sacs in the ovule nucellus and the development of embryos by parthenogenesis. In previous work, we reported a plant-specific TRIMETHYLGUANOSINE SYNTHASE 1 (TGS1) gene (PN_TGS1-like) showing expression levels positively correlated with sexuality rates in facultative apomictic Paspalum notatum. PN_TGS1-like displayed contrasting in situ hybridization patterns in apomictic and sexual plant ovules from premeiosis to anthesis. Here we transformed sexual P. notatum with a TGS1-like antisense construction under a constitutive promoter, in order to produce lines with reduced transcript representation. Antisense plants developed prominent trichomes on the adaxial leaf surface, a trait absent from control genotypes. Reproductive development analysis revealed occasional formation of twin ovules. While control individuals typically displayed a single meiotic embryo sac per ovule, antisense lines showed 12.93-15.79% of ovules bearing extra nuclei, which can be assigned to aposporous-like embryo sacs (AES-like) or, alternatively, to gametophytes with a misguided cell fate development. Moreover, around 8.42-9.52% of ovules showed what looked like a combination of meiotic and aposporous-like sacs. Besides, 32.5% of ovules at early developmental stages displayed nucellar cells with prominent nuclei resembling apospory initials (AIs), which surrounded the megaspore mother cell (MMC) or the MMC-derived meiotic products. Two or more concurrent meiosis events were never detected, which suggest a non-reduced nature for the extra nuclei observed in the mature ovules, unless they were generated by proliferation and misguided differentiation of the legitimate meiotic products. The antisense lines produced a similar amount of viable even-sized pollen with respect to control genotypes, and formed an equivalent full seed set (similar to 9% of total seeds) after self-pollination. Flow cytometry analyses of caryopses derived from antisense lines revealed that all full seeds had originated from meiotic embryo sacs (i.e. by sexuality). A reduction of 25.55% in the germination percentage was detected when comparing antisense lines with controls. Our results indicate that PN_TGS1-like influences ovule, gametophyte and possibly embryo development.