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As some of the oldest differentiated materials in our solar system, angrite meteorites can provide unique insights into the earliest stages of planetary evolution. However, the timing of planetary mixing, as evidenced by oxygen isotope variations in the quenched angrites, and the extent of magmatism on the angrite parent body (APB) remain poorly understood. Here, we report on microstructurally guided in situ geochemical and Pb–Pb isotopic measurements on angrites aimed at better understanding of the timing and nature of magmatic processes, as well as impact events, on the APB. The quenched angrite Northwest Africa (NWA) 12320 yielded a Pb–Pb date of 4571.2 ± 9.4 Ma, which we interpret as corresponding to the timing of planetary mixing. The only known shocked quenched angrite, NWA 7203, also yielded an ancient Pb–Pb date of 4562.9 ± 9.3 Ma, which is identical to the Pb–Pb date of 4563.6 ± 7.9 Ma obtained for the texturally intermediate angrite NWA 10463. Pb–Pb analyses in phosphates in the dunitic angrite NWA 8535 yielded a much younger date of 4514 ± 30 Ma, representing the youngest Pb–Pb date ever recorded for an angrite. Based on the evidence from the lack of shock deformation, olivine major and trace element compositions, and no apparent contamination in the oxygen isotope composition of NWA 8535, our findings are consistent with prolonged magmatism on the APB. This finding is consistent with a large size for the APB. [ABSTRACT FROM AUTHOR]

Constraining the timing and intensity of Solar System bombardment is critical to understanding planetary formation, evolution and habitability. However, the identification and dating of shockmetamorphic events in the mafic igneous lithologies that dominate planetary materials remains highly challenging, particularly at relatively modest shock pressures. The accessory mineral baddeleyite (monoclinic-ZrO2) is common in these mafic crustal rocks, though the microstructural response of this mineral to shock loading is currently unconstrained. Here we show that baddeleyite yields a predictable sequence of microstructures in the shock pressure range of 5 to ~20 GPa, based on analysis of mafic rocks collected along a well-constrained shock-pressure gradient in the crystalline bedrock of the Sudbury impact structure, Canada. High-resolution electron backscatter diffraction mapping of baddeleyite grains exposed to <20 GPa of shock loading reveals a range of microstructures, including complex orthogonally related crystalline subgrains, amorphous domains, and crystal plastic deformation. Evidence that the observed microstructures are principally controlled by the transition to, and subsequent reversion from, the high-pressure (experimentally constrained to >5 GPa) orthorhombic-ZrO2 polymorph is provided by phase-heritage reconstruction using relationships between reverted monoclinic orientations. Baddeleyite is a sensitive shock barometer and chronometer over low pressure ranges that can augment ongoing studies into the intensity of Solar System bombardment. [ABSTRACT FROM AUTHOR]

Introduction: The development of laser-assisted atom probe tomography (APT) has allowed for the analysis of non-conductive materials, including mineral specimens [1]. The ability for APT to generate 3D chemical reconstructions from < 100 nm crystallographic domains at high spatial (± 0.1 nm) and mass (1000 FWHM) resolution has provided fundamental insights into the mobility of radiogenic isotopes [2], volatile (Cl) fractionation and loss [3], and the distribution of H2O in nominally anhydrous olivine [4]. Recently, the technique has been applied to meteoritic and returned lunar samples, constraining the chemical artifacts induced by space weathering within lunar regolith [5] and quantifying Pb mobility and clustering in shocked zircon [2]. Here, we explore the ongoing applications of APT to lunar samples and highlight the importance of the technique going forward in unravelling nanoscale variations which are fundamentally linked with kilometre scale recent and ancient mechanisms on the Moon. Samples: A range of lunar samples have been analysed using APT, with an aim of targeting various isotopic or compositional signatures within a suite of mineral species. Northwest Africa (NWA) 3163 is a brecciated lunar meteorite, while Apollo samples 60500 (soil) and 78236 (shock deformed norite) represent samples returned by the Apollo missions. A range of mineral specimen were targeted within the samples (baddeleyite (ZrO2), anorthite (CaAl2Si2O8), and apatite (Ca5(PO4)3(Cl,OH,F))) to measure bulk chemistry and trace element abundances and target radiogenic (Pb) and volatile (Cl, F, OH) isotopic reservoirs within isolated nanodomains. Results: NWA 3163: A baddeleyite grain within a feldspathic clast in NWA 3163 contains two discrete microstructural domains: a polysynthetically twinned core (∼90°/<401>) and a uniquely oriented rim domain interpreted to represent overgrowth during a later metamorphic event. Targeted analysis of these domains yields resolvable Th and Pb isotopic signatures by APT, allowing the generation of Th-Pb ages from each microstructural domain. The core, which appears to retain igneous microstructure, records a 232Th/208Pb age of 4328 ± 309 (2σ) Ma. The < 2 μm wide overprinting rim yields a 232Th/208Pb age of 2175 ± 143 Ma (2σ). In combination, APT has allowed for robust isotopic dating of both the oldest and youngest events in NWA 3163 within a single baddeleyite grain less than 5 μm in total length [6]. Apollo 78236: An apatite grain within the highly shocked Mg-suite norite 78236 reveals various microstructural domains, including crystal plastically deformed crystalline areas and quasi-amorphous domains. Dating of the apatite and merrillite populations by SIMS reveal a discordant array of U-Pb ages between 4210 ± 14 Ma (upper intercept) and 504 ± 24 Ma (lower intercept) [7]. APT analysis of the quasi-amorphous apatite domains reveals polygonal grains separated by Mg-decorated subgrain boundaries which act as diffusion pathways to allow radiogenic isotope loss at lower temperatures than solid state diffusion through the crystal lattice. Correlative APT analysis is thus critical to accurately interpreting in-situ isotopic and chemical datasets, here placing empirical constraints on a young (500 Ma) lunar impact crater while also providing evidence for an ancient (4.2 Ga) formation age, interpreted to reflect formation of the Serinitatis basin [7]. Apollo 60500: An individual feldspar grain was targeted from the lunar soil. Initial data reveal the homogenous distribution of Al, Ca, Si, and trace elements throughout the 300 nm long microtip specimen. Species of isotopic importance, such as Ar, Pb, Sr, Rb and Sm, could not be confidently measured within the mass spectrum due to mass overlaps with complex AlSiO species and compounds, in agreement with previous APT measurements of feldspar [8]. Work is ongoing to constrain the influence of solar wind implantation within the surficial regions of the sample. Discussion: APT is a rapidly emerging tool in the geological and planetary sciences, holding great promise in answering large planetary scale questions with (sub) nanometre scale measurements [e.g., 6]. The minimally destructive nature of the technique (consuming less material than a typical LA-ICP-MS or SIMS spot) coupled with the potentially all-encompassing scientific yield (measuring the entire mass spectrum, with no mass bias or fractionation effects) is particularly critical for returned samples, where small amounts of material (from grams to single grains) are only available [7-9]. Future and ongoing sample return missions to the Moon, such as Chang'e 5, would benefit greatly from the inclusion of atom probe tomography in planned workflows of returned samples. [ABSTRACT FROM AUTHOR]

Introduction: CM carbonaceous chondrites are among the most chemically primitive meteorites, yet are also some of the most aqueously altered [1,2]. This pervasive parent body processing destroys much of the primary mineralogy and texture [2]. Nano-scale investigations indicate that the permeability of aqueously altered carbonaceous chondrites is low, permitting fluid flow only over distances <100 µm [3], and that aqueous alteration is locally heterogeneous [4]. In contrast, recent observations of large veins of carbonate on the B-type asteroid Bennu [5], which has spectroscopic similarities to CMs [6], suggest macro-scale movement of fluids. On the 28th February 2021 a bright fireball was observed by the UK Fireball Alliance (UKFall) [7]. This resulted in the recovery of the Winchcombe meteorite 12 hours later [7]. It is a CM chondrite breccia with eight distinct lithologies, with variable alteration histories ranging from CM2.0-CM 2.6 plus a cataclastic matrix [8]. The limited terrestrial alteration of Winchcombe, combined with the orbital parameters determined by UKFAll [7], make it an ideal sample to explore macro-nanoscale constraints on aqueous alteration of CM chondrites. Here, we present the key results of the investigations undertaken by the fine-grained sub-team of the Winchcombe consortium study. Methods: Several rock chips and petrographic sections of the Winchcombe meteorite were analysed using X-ray computed tomography (XCT), electron probe microanalysis (EPMA), scanning electron microscopy (SEM) techniques (including secondary electron (SE) and backscatter electron (BSE) imaging, energy dispersive X-ray spectrometry (EDS), QEMSCAN, electron backscatter diffraction (EBSD)), focused ion beam (FIB) microscopy (including FIB based time of flight secondary ion mass spectrometry (TOF-SIMS) transmission electron microscopy (TEM) techniques (including, HAADF, EELS, STEM, EDS, XANES), atom probe tomography (APT). Permeability at the macroscale were established via numerical simulations. Key results: XCT data indicate that some Winchcombe lithologies have a preferred alignment of relic ellipsoidal chondrules defining a foliation fabric. These foliations are in separate orientations in different lithologies from the same rock chip. Some lithologies also exhibit a 'fracture cleavage' defined by sub-parallel fracture sets. Numerical simulations indicate that Winchcombe has an anisotropic permeability with a much lower permeability along one axis. SEM imaging reveals a range from complete to incomplete replacement of carbonate and silicate phases in some tochilinite cronstedtite intergrowths (TCIs) with some carbonate-TCI grains separated by only a few 100 µm. EPMA data show a moderate spread of compositions within the matrix, fine-grained rims (FGR), and TCIs within each lithology. TEM investigations of an FGR around a chondrule within a subtype 2.2 lithology reveal the presence of inclusions that resemble glass with embedded metal and sulphide (GEMS). Coordinated TOF-SIMS and APT data indicate that Na is concentrated at the boundary between Mg-rich and Fe-rich serpentine intergrowths in TCIs. Discussion and conclusions: At the macro-scale, XCT results and numerical simulations show that fluids flowed more readily along a 2D plane and less-readily along the pole to that plane. Such an anisotropic permeability network may be generated via compaction or through precipitation of minerals during aqueous alteration, and would serve to limit fluid transfer, resulting in the segregation of fluid compositions which may enhance the preservation of pockets of unaltered material. At the nanoscale, the survival of both GEMS-like phases that are readily altered by minor degrees of aqueous alteration, and the heterogeneity in the extent of carbonate alteration to TCIs over short distances, suggest that regions within otherwise severely aqueously altered regions of the Winchcombe meteorite experienced little fluid interaction. This was likely caused by local variations in permeability on the Winchcombe parent. The cause of this lower permeability that limited fluid migration to reactive surfaces could be a primary texture, a compaction texture, an impact texture, or generated by progressive alteration. Therefore, even in pervasively aqueously altered meteorites it is likely that some nano-macro scale volumes can preserve their primary mineralogy and texture. [ABSTRACT FROM AUTHOR]

Introduction: The formation and migration of giant gas planets are crucial to the evolution of planetary systems, and yet the timing of these events in our Solar System remains largely unconstrained. Angrite meteorites represent some of the oldest materials in the inner Solar System, and therefore provide an exclusive window into the history of the early Solar System [1]. Recent oxygen isotopic analyses have redefined the angrite fractionation line (AFL) to Δ17O = 0.064 ± 0.018‰ (2s) and highlighted that the quenched angrite NWA 12320 exhibits an anomalous Δ17O value of -0.017 ± 0.004‰ (2s) [2]. Mineralogically, NWA 12320 is comparable to the majority of quenched angrites, however, it lacks the usual abundance of olivine xenocrysts. Here we present evidence for an oxygen isotopic disequilibrium between the matrix and olivine xenocrysts in three quenched angrites, NWA 12320, Asuka-12209 and Asuka-881371, discussing the possible causes of this variation. Matrials and Methods: Olivine xenocrysts in the three quenched angrites were separated from the matrix and subsequent O-isotope data of both matrix and olivine fractions were obtained at the Open University using laserassisted fluorination following established procedures [3,4]. Results: The olivine xenocrysts of NWA 12320, Asuka 12209 and Asuka 881371 display Δ17O values of - 0.065 ± 0.018‰, -0.068 ± 0.015‰ and -0.067 ± 0.008‰, respectively, indistinguishable from whole-rock angrite meteorites measured in other studies [2]. Intriguingly, the matrix fractions of all three samples reveal less negative values that are statistically distinct from the other angrite meteorites (Δ17O = -0.024 ± 0.016‰, -0.001 ± 0.007‰ and -0.003 ± 0.007‰, respectively). While lesser amounts of matrix may result in undetectable shifts in some quenched angrites, NWA 12320 is dominated by matrix and therefore the whole-rock sample equates to a matrix separate. Electron backscatter diffraction on the olivine xenocrysts in NWA 12320 revealed granular textures. The granular olivine xenocrysts have no discernible preferred orientation and are cemented by olivine with a higher Fe content, with neighbouring grains displaying vastly distinct orientations, indicative of recrystallization, after shockinduced mosaicism or fragmentation. Discussion: The granular textures within NWA 12320, have also been reported in the urelite JaH 422 and the howardite JaH 556 [5,6]. These meteorites have been interpreted as impact-melt rocks with the olivine grains representing unmolten relics of their precursor material. Interestingly, JaH 556 similarly displayed slight oxygen isotopic differences between the bulk-rock and matrix fractions. This textural evidence could suggest that at least some olivine grains in NWA 12320 remained as relict material and were affected by high temperature processes on the angrite parent body (APB). We therefore favor the hypothesis that NWA 12320, Asuka 12209 and Asuka 881371 have an impact-melt origin, with the matrix representing recrystallized material induced by an impact event and the olivine grains representing relict material of the original APB. The impactor is unlikely to be a carbonaceous chondrite based on the positive Δ17O values of the matrix, nor an ordinary chondrite due to the lack of metal within angrite meteorites. We therefore propose that the impactor was an unsampled achondrite like NWA 11042 [7]. We conclude that this extreme dynamical excitement resulting in early, large scale mixing, is not an expected result of the classical accretion of bodies, and demands the interference of the giant gas planets. Summary: We interpret our findings in terms of quenched angrite meteorites representing impact-melt rocks rather than shallow magmatic intrusions, recording evidence of impact-driven mixing. This mixing may have taken place in response to the inward migration of giant planets (as envisaged in the Grand Tack model [8]) and hence would represent the earliest isotopic evidence for planetary migration in the early Solar System. [ABSTRACT FROM AUTHOR]

Abstracts from various medical journals are presented. "Endolymphatic Sac Surgery for Ménière's Disease: Long-term Results After Primary and Revision Surgery," from "Archives of Otolaryngology - Head and Neck Surgery" is presented. "Familial Predisposition for Psychiatric Disorder: Comparison of Subjects Treated for Cannabis-Induced Psychosis and Schizophrenia," from "Archives of General Psychiatry" is presented. "The Impact of a Vision Screening Law on Older Driver Fatality Rates," from "Archives of Opthalmology" is presented.

Accurate testing and treatment for latent tuberculous infection is necessary for tuberculosis elimination. Certain parasite infections are associated with increased tuberculin skin test positivity; species-specific effects on QuantiFERON ® -TB Gold In-Tube (QGIT) have not been described. To determine whether infection with helminths or protozoa affects QGIT results. We retrospectively analyzed QGIT and parasite testing results for immigrants screened in Boston, MA, USA, from 2012 to 2017. We also prospectively measured cytokines in QGIT supernatants for a subset ( n = 68) with 1) helminths, 2) Blastocystis hominis , 3) other protozoa, and 4) no parasites. Of 527 immigrants screened, 141 (26.8%) were QGIT-positive and 229 (43.4%) had parasites detected: 27/527 (5.1%) had helminths and 202/527 (38.3%) protozoa. Cytokine analysis revealed increased interleukin-10 concentrations with protozoa ( P = 0.04), and non-significantly higher T-helper 2 concentrations with helminths compared with no parasites. No significant differences emerged in QGIT positivity or interferon-gamma concentrations in any group. Study results support the use of QGIT in parasite-endemic settings. .

Setting: In early studies, Xpert® MTB/RIF accurately detected culture-proven pulmonary tuberculosis (TB). Recent reports have, however, found a lower than expected specificity in previously treated TB patients., Objective: To investigate the diagnostic accuracy of Xpert in presumptive pulmonary TB patients in Southwestern Uganda., Design: We obtained demographic and clinical information and collected three sputum samples from each patient for smear microscopy, Xpert and culture. We estimated Xpert sensitivity and specificity against culture, and stratified the analysis by previous treatment and sputum quality status., Results: We analyzed results from 860 presumptive TB patients, including 109 (13%) with a previous history of anti-tuberculosis treatment; 205 (24%) were culture-positive. Xpert specificity was lower (91.8%, 95%CI 84.9-96.2) in previously treated than in new TB patients (97.5%, 95%CI 96.1-98.5; P = 0.01). In an adjusted analysis, patients with culture-, Xpert+ results were more likely to have been previously treated for TB (OR 8.3, 95%CI 2.1-32.0; P = 0.002), and to have mucosalivary sputum (OR 4.1, 95%CI 1.1-14.6; P = 0.03), but were less likely to self-report fever (OR 0.23, 95%CI 0.1-0.7; P = 0.008) than patients with concordant positive results., Conclusion: Xpert specificity was lower in previously treated patients with suspected TB. The clinical and programmatic impact of culture-, Xpert+ results requires evaluation in future studies.

Background: Sarcoidosis is a chronic systemic granulomatous disease of unknown etiology that disproportionately affects black females.  Few studies have specifically addressed causes of death in this population., Objectives: To assess rates and causes of death among women with sarcoidosis in a prospective cohort study of U.S. black women., Design: The Black Women's Health Study is a follow-up study of 59,000 U.S. black women aged 21-69 (median age 38) at entry in 1995.  Data on demographic and lifestyle factors and medical conditions, including sarcoidosis, were obtained through biennial questionnaires.  Deaths and causes of death from 1995 through 2009 among study subjects were identified from National Death Index data. We assessed mortality rates among women with and without a history of sarcoidosis.  Poisson regression models were used to estimate age-adjusted mortality rates. Cox proportional-hazards models were used to estimate hazard ratios for mortality and 95% confidence intervals., Results: A total of 121 deaths occurred among 1,192 women with a history of sarcoidosis and 2813 deaths among women without sarcoidosis.  Mortality was greater at every age among women with sarcoidosis and the overall multivariable-adjusted hazard ratio was 2.44 (95% CI 2.03-2.93, p&lt;0.0001). Of the deaths among women with sarcoidosis, 24.7% were directly attributable to sarcoidosis., Conclusions: In the Black Women's Health Study, women with sarcoidosis were more than twice as likely to die as women without the disease, with many of the deaths directly attributable to sarcoidosis.  Sarcoidosis is an important cause of premature death among black women with the disease.