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A new container-less droplet merging method in combination with high-speed imaging and spectroscopy were employed to explore the chemistry in the initial stages of ignition in a hyperogolic ionic liquid – oxidizer reaction.

In the past decade it has become evident that neuroblasts continue to supply the human cortex with interneurons via unique migratory streams shortly following birth. Owing to the size of the human brain, these newborn neurons must migrate long distances through complex cellular landscapes to reach their final locations. This process is poorly understood, largely because of technical difficulties in acquiring and studying neurotypical postmortem human samples along with diverging developmental features of well-studied mouse models. We reasoned that migratory streams of neuroblasts utilize cellular substrates, such as blood vessels, to guide their trek from the subventricular zone to distant cortical targets. Here, we evaluate the association between young interneuronal migratory streams and their preferred cellular substrates in gyrencephalic piglets during the developmental equivalent of human birth, infancy, and toddlerhood. US National Institutes of Health [R15NS108183] Published version ACKNOWLEDGMENTS We gratefully thank Drs. Sherrie Clark-Deener and Calvin Lau for their assistance with veterinary services. We are also thankful to Jessica Neary and Garrett Walker for assistance in animal husband-ry. We also would like to thank Raymundo Hernandez, Beatriz Torres, Swagatika Paul, and Dr. Alicia Pickrell for technical advice. We would like to acknowledge Karen Hall and Rachel McNeil for animal care. This work was supported by the US National Institutes of Health (R15NS108183 to P.D.M.) .

Iron is an essential nutrient that regulates productivity in ~30% of the ocean. Compared with deep (>2000 meter) hydrothermal activity at mid-ocean ridges that provide iron to the ocean’s interior, shallow (2 .

The chemical composition of gases emitted by active volcanoes reflects both magma degassing and shallower processes, such as fluid-rock hydrothermal interaction and mixing with atmospheric-derived fluids. Untangling the magmatic fluid endmember within surface gas emission is therefore challenging, even with the use of well-known magma degassing tracers such as noble gases. Here, we investigate the deep magmatic fluid composition at the Nisyros caldera (Aegean Arc, Greece) by measuring nitrogen and noble gas abundances and isotopes in naturally degassing fumaroles. Gas samples were collected from 32 fumarolic vents at water-boiling temperature between 2018 and 2021. These fumaroles are admixtures of magmatic fluids typical of subduction zones, groundwater (or air saturated water, ASW), and air. The N2, He, and Ar composition of the magmatic endmember is calculated by reverse mixing modeling and shows N2/He = 31.8 ± 4.5, N2/Ar = 281.6, δ15N = +7 ± 3 ‰, 3He/4He = 6.2 Ra (where Ra is air 3He/4He), and 40Ar/36Ar = 551.6 ± 19.8. Although N2/He is significantly low with respect to typical values for arc volcanoes (1,000–10,000), the contribution of subducted sediments to the Aegean Arc magma generation is reflected by the positive δ15N values of Nisyros fumaroles. The low N2/He ratio indicates N2-depletion due to solubility-controlled differential degassing of an upper-crustal silicic (dacitic/rhyodacitic) melt in a high-crystallinity reservoir. We compare our 2018–2021 data with N2, He, and Ar values collected from the same fumaroles during a hydrothermal unrest following the seismic crisis in 1996–1997. Results show additions of both magmatic fluid and ASW during this unrest. In the same period, fumarolic vents display an increase in magmatic species relative to hydrothermal gas, such as CO2/CH4 and He/CH4 ratios, an increase of ∼50 °C in the equilibrium temperature of the hydrothermal system (up to 325 °C), and greater amounts of vapor separation. These variations reflect an episode of magmatic fluid expulsion during the seismic crisis. The excess of heat and mass supplied by the magmatic fluid injection is then dissipated through boiling of deeper and peripheral parts of the hydrothermal system. Reverse mixing modeling of fumarolic N2-He-Ar has therefore important ramifications not only to disentangle the magmatic signature from gases emitted during periods of dormancy, but also to trace episodes of magmatic outgassing and better understand the state of the upper crustal reservoir., Geochimica et Cosmochimica Acta, 335, ISSN:0016-7037, ISSN:1872-9533

Background Despite having a high healthcare need, persons with complex conditions are less likely to receive comprehensive care. Individuals with SCI experience difficulties accessing services 2-4 times more than the general population. There is little agreement concerning the factors that influence these access restrictions. Few studies focus on health system impact on characteristics on access. Objective To outline barriers and facilitators to service access among persons with SCI across 22 countries in terms of health system characteristics Methods InSCI(2017): 1st community survey on experience of persons with SCI, 12591 participants, 22 countries (Australia, Brazil, China, France, Germany, Greece, Indonesia, Italy, Japan, Lithuania, Malaysia, Morocco, the Netherlands, Norway, Poland, Romania, South Africa, South Korea, Spain, Switzerland, Thailand, USA). Data analysis 1. Hierarchical cluster analysis based on Gower distance (to group systems by access restrictions: Acceptability, Approachability, Availability, Affordability, Appropriateness). 2. Generalized linear mixed-effects decision tree (to explore the association of system characteristics and access, including WHO and OECD system indicators (e.g. UHC index, expenditure, human resources). Missing values were imputed with missforest. Results 12% of persons with SCI reported having an access restriction, most of them (7%) with Availability. By country, the highest unmet needs were reported in Poland (25%), Germany, Lithuania, and Romania (13). 1. Cluster analysis: 7 health systems clusters (groups) were identified. 2. By June 2022, we will have the results of the second analysis: the association of system characteristics with access and how it is modified by socio-demographic and medical factors. Expected conclusions The study identifies factors a country could modify in order to improve access and strengthen the system for persons with SCI/disability, that might be relevant to general population as well. Key messages • Persons with SCI often experience similar access restrictions across countries, incl. those with high-performing health systems. System strengthening in this area is further required in all countries. • Health systems are fragmented, e.g. healthcare quality and access inside a country differs by region, urban/rural setting etc., hence, the systems are challenging to classify.

Post-orogenic back-arc magmatism is accompanied by hydrothermal ore deposits and mineralizations derived from mantle and crustal sources. We investigate Zannone Island (ZI), back-arc Tyrrhenian basin, Italy, to define the source(s) of mineralizing hydrothermal fluids and their relationships with the regional petrological-tectonic setting. On ZI, early Miocene thrusting was overprinted by late Miocene post-orogenic extension and related hydrothermal alteration. Since active submarine hydrothermal outflow is reported close to the island, Zannone provides an ideal site to determine the P-T-X evolution of the long-lived hydrothermal system. We combined field work with microstructural analyses on syn-tectonic quartz veins and carbonate mineralizations, X-ray diffraction analysis, microthermometry and element mapping of fluid inclusions (FIs), C, O, and clumped isotopes, and analyses of noble gases (He-Ne-Ar) and CO2 content in FIs. Our results document the evolution of a fluid system of magmatic origin with increasing mixing of meteoric fluids. Magmatic fluids were responsible for quartz veins precipitation at similar to 125 to 150 MPa and similar to 300 degrees C-350 degrees C. With the onset of extensional faulting, magmatic fluids progressively interacted with carbonate rocks and mixed with meteoric fluids, leading to (a) host rock alteration with associated carbonate and minor ore mineral precipitation, (b) progressive fluid neutralization, (c) cooling of the hydrothermal system (from similar to 320 degrees C to similar to 86 degrees C), and (d) embrittlement and fracturing of the host rocks. Both quartz and carbonate mineralizations show noble gases values lower than those from the adjacent active volcanic areas and submarine hydrothermal systems, indicating that the fossil-to-active hydrothermal history is associated with the emplacement of multiple magmatic intrusions., Geochemistry, Geophysics, Geosystems, 23 (10), ISSN:1525-2027

Constraining the magmatic 3He/4He signature of fluids degassed from a magmatic system is crucial for making inferences on its mantle source. This is especially important in arc volcanism, where variations in the composition of the wedge potentially induced by slab sediment fluids must be distinguished from the effects of magma differentiation, degassing, and crustal contamination. The study of fluid inclusions (FIs) trapped in minerals of volcanic rocks is becoming an increasingly used methodology in geochemical studies that integrates the classical study of volcanic and geothermal fluids. Here, we report on the first noble gas (He, Ne, Ar) concentrations and isotopic ratios of FI in olivine (Ol) and pyroxene (Px) crystals separated from eruptive products of the Telica and Baru volcanoes, belonging to the Nicaraguan and Panamanian arc-segments of Central America Volcanic arc (CAVA). FIs from Telica yield air corrected 3He/4He (Rc/Ra) of 7.2–7.4 Ra in Ol and 6.1–7.3 in Px, while those from Baru give 7.1–8.0 Ra in Ol and 4.2–5.8 Ra in Px. After a data quality check and a comparison with previous 3He/4He measurements carried out on the same volcanoes and along CAVA, we constrained a magmatic Rc/Ra signature of 7.5 Ra for Telica and of 8.0 Ra for Baru, both within the MORB range (8 ± 1 Ra). These 3He/4He differences also reflect variations in the respective arc-segments, which cannot be explained by radiogenic 4He addition due to variable crust thickness, as the mantle beneath Nicaragua and Panama is at about 35 and 30 km, respectively. We instead highlight that the lowest 3He/4He signature observed in the Nicaraguan arc segment reflects a contamination of the underlying wedge by slab sediment fluids. Rc/Ra values up to 9.0 Ra are found at Pacaya volcano in Guatemala, where the crust is 45 km thick, while a 3He/4He signature of about 8.0 Ra was measured at Turrialba volcano in Costa Rica, which is similar to that of Baru, and reflects possible influence of slab melting, triggered by a change in subduction conditions and the contemporary subduction of the Galapagos hot-spot track below southern Costa Rica and western Panama.

The 2021 eruption of Cumbre Vieja volcano (La Palma Island) is one of the largest natural disasters in Europe in recent times, but also a unique opportunity for monitoring the evolution of a volcanic system and its underlying mantle source.Geophysical and geochemical evidence suggests that volcanism in Canary Islands is driven by the presence of a mantle plume, even though helium isotopes highlight this lower mantle component (3He/4He>9 Ra) only in the Dos Aguas spring gases and the older lavas from the Taburiente caldera (north of La Palma). Conversely, fluid inclusions in lavas and spring gases from the recent Cumbre Vieja system have a MORB-like signature (8±1 Ra). These distinct signatures were ascribed to the mixing between different mantle components (Day and Hilton, 2020). In this framework, the 2021 Cumbre Vieja eruption opens new avenues to investigate the current composition of the local mantle and test the pre-existing models.Here, we present the first insights into the 3He/4He signature of volcanic gases and phenocryst-hosted fluid inclusions from lavas erupted by the Cumbre Vieja in September-November 2021. For comparison, we analyzed the poorly evolved lavas from 1677 San Antonio eruption bearing mantle xenoliths (South of Cumbre Vieja) and a 3 Ma old picrite cropping out in the Taburiente caldera, close to the Dos Aguas spring (Day et al., 2010).The 2021 lavas belonging to the October 27th and November 9th flows are basanite tephrites, with an average Mg# of 58.6, being more mafic than those from the September opening phase (Mg# = 50.3; Pankhurst et al., 2022). Olivine phenocrysts have Fo content mostly of mostly 78-83, and elevated Al and Cr contents. The estimated T based on the Cr and Al in olivine thermometers (DeHoog et al., 2010) is 920-960°C.The 3He/4He ratio in phenocryst-hosted fluid inclusions from the 2021 products is 7-7.5 Ra, confirming the MORB-like signature of the volcanic products and gases dissolved in water of the Cumbra Vieja system (Day and Hilton, 2020; Torres-Gonzalez et al., 2020). Instead, the olivines in the Taburiente picrite yield 9.4±0.1 Ra, comparable to values in the Dos Aguas spring, confirming the existence of a lower mantle component below this sector of the island.The distinct 3He/4He signature observed at Taburiente and Cumbre Vieja products is preliminary interpreted as due to either (i) small-scale heterogeneities in the local mantle, and/or (ii) a plumbing system effect that lowers the 3He/4He of the recently erupted magmas. In the latter case, magma differentiation and degassing at the crust-mantle boundary or even deeper in the mantle, coupled to the production and accumulation of radiogenic 4He, would play a central role.REFERENCESDay, J.M.D., et al. 2010, Geochimica et Cosmochimica Acta, v. 74, p. 6565–6589.Day, J.M.D., Hilton, D.R., 2020. Geology.De Hoog, J. C., Gall, L., & Cornell, D. H., 2010. Chemical Geology, 270(1-4), 196-215.Pankhurst, M. J., et al., 2022. Volcanica, 5, 1-10.Torres-González, P. A. et al., 2020. J. Volcanol. Geotherm. Res. 392, 106757.

Lithium carbonate is a commonly prescribed drug for bipolar disorders. In addition to its action on the central nervous system, lithium has systemic effects on multiple organs such as kidney, heart, motor end plate, thyroid and parathyroid glands. It can cause hypothyroidism, hyperthyroidism, goiter and ophthalmopathy by different mechanisms. It increases intrathyroid iodine content or compete for iodine transport, resulting in low iodine uptake by the thyroid. It also inhibits the coupling of iodotyrosine residues to form iodothyronines and inhibits the release of T4 and T3. Lithium has direct actions on parathyroid glands by antagonizing the calcium sensing receptor, which may induce hypercalcemia or even hyperparathyroidism, requiring surgery in some cases. Furthermore, it inhibits the expression of aquaporins, mainly aquaporin 2, in the renal collecting tubule by unknown mechanisms leading to nephrogenic diabetes insipidus. This adverse effect is usually reversible after drug withdrawal. However, some patients may present irreversible kidney damage due to chronic interstitial nephropathy.El carbonato de litio es un fármaco que se prescribe comúnmente para el tratamiento de trastornos bipolares. Además de su acción sobre el sistema nervioso central, el litio tiene repercusiones sistémicas, afectando a múltiples órganos como el riñón, el corazón, la placa motora terminal y glándulas tiroides y paratiroides. Puede causar hipotiroidismo, hipertiroidismo, bocio y oftalmopatía por diferentes mecanismos; también aumentar el contenido de yodo intratiroideo o competir por el transporte de yodo, lo que resulta en una baja captación tiroidea de yodo. Inhibe el acoplamiento de residuos de yodotirosina para formar yodotironinas e inhibe la liberación de T4 y T3. Tiene acciones directas sobre las glándulas paratiroides antagonizando el receptor sensor de calcio, lo que puede inducir hipercalcemia e incluso hiperparatiroidismo, y puede requerir cirugía en algunos casos. Inhibe la expresión de acuaporinas en el túbulo colector renal, principalmente acuaporina 2, por mecanismos que aún no se conocen, produciendo diabetes insípida nefrogénica; este efecto adverso suele ser reversible tras la suspensión del fármaco. Sin embargo, algunos pacientes pueden presentar daño renal irreversible por nefropatía intersticial crónica.

The investigation of the role played by CO2 circulating within the mantle during partial melting and metasomatic/refertilization processes, together with a re-consideration of its storage capability and re-cycling in the lithospheric mantle, is crucial to unravel the Earth's main geodynamic processes. In this study, the combination of petrology, CO2 content trapped in bulk rock- and mineral-hosted fluid inclusions (FI), and 3D textural and volumetric characterization of intra- and inter-granular microstructures was used to investigate the extent and modality of CO2 storage in depleted and fertile (or refertilized) Sub-Continental Lithospheric Mantle (SCLM) beneath northern Victoria Land (NVL, Antarctica). Prior to xenoliths entrainment by the host basalt, the Antarctic SCLM may have stored 0.2 vol% melt and 1.1 vol% fluids, mostly as FI trails inside mineral phases but also as inter-granular fluids. The amount of CO2 stored in FI varies from 0.1 μg(CO2)/g(sample) in olivine from the anhydrous mantle xenoliths at Greene Point and Handler Ridge, up to 187.3 μg/g in orthopyroxene from the highly metasomatized amphibole-bearing lherzolites at Baker Rocks, while the corresponding bulk CO2 contents range from 0.3 to 57.2 μg/g. Irrespective of the lithology, CO2 partitioning is favoured in orthopyroxene and clinopyroxene-hosted FI (olivine: orthopyroxene = 0.10 ± 0.06 to 0.26 ± 0.09; olivine: clinopyroxene = 0.10 ± 0.05 to 0.27 ± 0.14). The H2O/(H2O + CO2) molar ratios obtained by comparing the CO2 contents of FI to the H2O amount retained in pyroxene lattices vary between 0.72 ± 0.17 and 0.97 ± 0.03, which is well comparable with the values measured in olivine-hosted melt inclusions from Antarctic primary lavas and assumed as representative of the partition of volatiles at the local mantle conditions. From the relationships between mineral chemistry, thermo-, oxy-barometric results and CO2 contents in mantle xenoliths, we speculate that relicts of CO2-depleted mantle are present at Greene Point, representing memory of a CO2-poor tholeiitic refertilization related to the development of the Jurassic Ferrar large magmatic event. On the other hand, a massive mobilization of CO2 took place before the (melt-related) formation of amphibole veins during the alkaline metasomatic event associated with the Cenozoic rift-related magmatism, in response to the storage and recycling of CO2-bearing materials into the Antarctica mantle likely induced by the prolonged Ross subduction.

Public school administrators in the United States are required to supervise special education services, which include physical education and adapted physical education (APE). Although school administrators supervise and provide resources to support APE services, APE teachers have indicated that school administrators often interfere with their day-to-day practices and instruction. Thus, the purpose of this study was to examine school administrators’ beliefs, attitudes, and intentions toward supporting APE within their school. Using a qualitative description approach, guided by the theory of planned behavior, nine building principals from California were interviewed about their perceptions and past experiences with APE. A thematic analysis enabled the authors to construct three interconnected themes: (1) APE teachers and services are valued, yet not prioritized, (2) stakeholders’ support of APE can impact principals’ attitudes and support of APE; yet, many remain indifferent regarding support of APE, and (3) lack of knowledge, resources, and funding prevents principals from providing adequate support to APE services and teachers. These findings emphasize both the support and barriers building principals often contribute to APE teachers’ service delivery. Additionally, these findings highlight the important role administrators have in supporting APE teachers and creating a culture where APE services and teachers are valued. Future research designed to improve attitudes among school administrators toward APE is necessary. Moreover, to provide essential resources for effective APE service delivery, systematic and theoretically driven interventions that link knowledge to fill the APE knowledge gap among school administrators are warranted.