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The spectral properties of anhydrous carbonates and nitrates are dominated by strong, sharp vibrational bands due to the CO32− and NO3− anions observed as absorption bands in near‐infrared spectra, as Reststrahlen features or absorption bands in mid‐IR spectra, depending on particle size, and as peaks in Raman spectra. These spectral features provide a reliable means to identify the occurrence of carbonates and nitrates on planetary surfaces, which in turn contribute to our understanding of the environment and chemistry of planetary bodies. Four modes occur for carbonates and nitrates due to symmetric stretching (ν1), out‐of‐plane bending (ν2), asymmetric stretching (ν3), and in‐plane bending (ν4). The vibrational absorptions of these spectral features vary with the mineral structure and the size of the cation, where the calcite‐, dolomite‐, aragonite‐, and alkali‐type structures result in different spectral features. Mid‐IR bands for carbonates and nitrates occur from 1,040 to 1,105 cm−1 for ν1, from 810 to 906 cm−1 for ν2, from 1,275 to 1,590 cm−1 for ν3, and from 670 to 756 cm−1 for ν4. In Raman spectra the carbonate and nitrate absorptions are observed near 1,050–1,080 cm−1 for ν1, near 880 cm−1 for ν2, near 1,415–1,430 cm−1 for ν3, and near 680–700 cm−1 for ν4. NIR spectra include bands due to overtones and combinations at ∼1.75, 1.9, 2.0, 2.3, 2.5, 3.4, 4.0, and 4.6 μm for carbonates and ∼1.8, 2.0, 2.2, 2.4, 2.6, 3.5, 4.1, and 4.8 μm for nitrates. This study provides data for remote determination of carbonate and nitrate chemistry and will enable better characterization of these minerals on planetary bodies including Mars, Ceres, and Bennu. Plain Language Summary Carbonates are widespread minerals on Earth and have been identified as well on Mars, Ceres, near Earth asteroid (101955) Bennu, and in carbonaceous meteorites. Understanding the spectral properties of carbonates enables detection and characterization of this important mineral group. Furthermore, identifying the specific type of carbonate on planetary surfaces can help us constrain the geochemical environment of these planets or bodies. The spectral properties of nitrates are presented here as well because nitrates exhibit similar spectral features to carbonates due to their similar mineral structures. Nitrates are yet to be detected on planets other than Earth, but nitrogen has been detected on bodies in our Solar System and nitrates may be detected once researchers have access to their spectral properties. Key Points Spectral bands are presented for remote detection of anhydrous carbonates and nitrates Mid‐IR band center comparisons for the ν3 vibration compared to the ν2 and ν4 vibrations enable identification of carbonate chemistry NIR band center comparisons for ∼2.3 versus 2.5 μm, ∼2.3 versus 4 μm, and ∼3.4 versus 4 μm best enable identification of carbonate chemistry

Columbus crater in the Terra Sirenum region of the Martian southern highlands contains light‐toned layered deposits with interbedded sulfate and phyllosilicate minerals, a rare occurrence on Mars. Here we investigate in detail the morphology, thermophysical properties, mineralogy, and stratigraphy of these deposits; explore their regional context; and interpret the crater's aqueous history. Hydrated mineral‐bearing deposits occupy a discrete ring around the walls of Columbus crater and are also exposed beneath younger materials, possibly lava flows, on its floor. Widespread minerals identified in the crater include gypsum, polyhydrated and monohydrated Mg/Fe‐sulfates, and kaolinite; localized deposits consistent with montmorillonite, Fe/Mg‐phyllosilicates, jarosite, alunite, and crystalline ferric oxide or hydroxide are also detected. Thermal emission spectra suggest abundances of these minerals in the tens of percent range. Other craters in northwest Terra Sirenum also contain layered deposits and Al/Fe/Mg‐phyllosilicates, but sulfates have so far been found only in Columbus and Cross craters. The region's intercrater plains contain scattered exposures of Al‐phyllosilicates and one isolated mound with opaline silica, in addition to more common Fe/Mg‐phyllosilicates with chlorides. A Late Noachian age is estimated for the aqueous deposits in Columbus, coinciding with a period of inferred groundwater upwelling and evaporation, which (according to model results reported here) could have formed evaporites in Columbus and other craters in Terra Sirenum. Hypotheses for the origin of these deposits include groundwater cementation of crater‐filling sediments and/or direct precipitation from subaerial springs or in a deep (∼900 m) paleolake. Especially under the deep lake scenario, which we prefer, chemical gradients in Columbus crater may have created a habitable environment at this location on early Mars.

Analyses of MRO/CRISM images of the greater Mawrth Vallis region of Mars affirm the presence of two primary phyllosilicate assemblages throughout a region ∼1000 × 1000 km. These two units consist of an Fe/Mg‐phyllosilicate assemblage overlain by an Al‐phyllosilicate and hydrated silica assemblage. The lower unit contains Fe/Mg‐smectites, sometimes combined with one or more of these other Fe/Mg‐phyllosilicates: serpentine, chlorite, biotite, and/or vermiculite. It is more than 100 m thick and finely layered at meter scales. The upper unit includes Al‐smectite, kaolin group minerals, and hydrated silica. It is tens of meters thick and finely layered as well. A common phyllosilicate stratigraphy and morphology is observed throughout the greater region wherever erosional windows are present. This suggests that the geologic processes forming these units must have occurred on at least a regional scale. Sinuous ridges (interpreted to be inverted channels) and narrow channels cut into the upper clay‐bearing unit suggesting that aqueous processes were prevalent after, and possibly during, the deposition of the layered units. We propose that layered units may have been deposited at Mawrth Vallis and then subsequently altered to form the hydrated units. The Fe/Mg‐phyllosilicate assemblage is consistent with hydrothermal alteration or pedogenesis of mafic to ultramafic rocks. The Al‐phyllosilicate/hydrated silica unit may have formed through alteration of felsic material or via leaching of basaltic material through pedogenic alteration or a mildly acidic environment. These phyllosilicate‐bearing units are overlain by a darker, relatively unaltered, and indurated material that has probably experienced a complex geological history.

Tau plays a key role in Alzheimer’s disease (AD) pathophysiology, and accumulating evidence suggests that lowering tau may reduce this pathology. We sought to inhibit MAPT expression with a tau-targeting antisense oligonucleotide (MAPT Rx ) and reduce tau levels in patients with mild AD. A randomized, double-blind, placebo-controlled, multiple-ascending dose phase 1b trial evaluated the safety, pharmacokinetics and target engagement of MAPT Rx . Four ascending dose cohorts were enrolled sequentially and randomized 3:1 to intrathecal bolus administrations of MAPT Rx or placebo every 4 or 12 weeks during the 13-week treatment period, followed by a 23 week post-treatment period. The primary endpoint was safety. The secondary endpoint was MAPT Rx pharmacokinetics in cerebrospinal fluid (CSF). The prespecified key exploratory outcome was CSF total-tau protein concentration. Forty-six patients enrolled in the trial, of whom 34 were randomized to MAPT Rx and 12 to placebo. Adverse events were reported in 94% of MAPT Rx -treated patients and 75% of placebo-treated patients; all were mild or moderate. No serious adverse events were reported in MAPT Rx -treated patients. Dose-dependent reduction in the CSF total-tau concentration was observed with greater than 50% mean reduction from baseline at 24 weeks post-last dose in the 60 mg (four doses) and 115 mg (two doses) MAPT Rx groups. Clinicaltrials.gov registration number: NCT03186989 . Evaluation of a tau-targeting antisense oligonucleotide in a phase 1 trial of patients with mild AD found it was well tolerated and resulted in a sustained reduction of tau protein levels.

Mutated HTT , resulting in mutant huntingtin, causes Huntington’s disease. A phase 1–2a trial of intrathecal delivery of an antisense oligonucleotide targeting HTT mRNA in 34 persons with Huntington’s disease showed a dose-dependent reduction of mutant huntingtin in cerebrospinal fluid and no serious adverse events in those who received the drug.

Azithromycin, an antibiotic with potential antiviral and anti-inflammatory properties, has been used to treat COVID-19, but evidence from community randomised trials is lacking. We aimed to assess the effectiveness of azithromycin to treat suspected COVID-19 among people in the community who had an increased risk of complications. In this UK-based, primary care, open-label, multi-arm, adaptive platform randomised trial of interventions against COVID-19 in people at increased risk of an adverse clinical course (PRINCIPLE), we randomly assigned people aged 65 years and older, or 50 years and older with at least one comorbidity, who had been unwell for 14 days or less with suspected COVID-19, to usual care plus azithromycin 500 mg daily for three days, usual care plus other interventions, or usual care alone. The trial had two coprimary endpoints measured within 28 days from randomisation: time to first self-reported recovery, analysed using a Bayesian piecewise exponential, and hospital admission or death related to COVID-19, analysed using a Bayesian logistic regression model. Eligible participants with outcome data were included in the primary analysis, and those who received the allocated treatment were included in the safety analysis. The trial is registered with ISRCTN, ISRCTN86534580. The first participant was recruited to PRINCIPLE on April 2, 2020. The azithromycin group enrolled participants between May 22 and Nov 30, 2020, by which time 2265 participants had been randomly assigned, 540 to azithromycin plus usual care, 875 to usual care alone, and 850 to other interventions. 2120 (94%) of 2265 participants provided follow-up data and were included in the Bayesian primary analysis, 500 participants in the azithromycin plus usual care group, 823 in the usual care alone group, and 797 in other intervention groups. 402 (80%) of 500 participants in the azithromycin plus usual care group and 631 (77%) of 823 participants in the usual care alone group reported feeling recovered within 28 days. We found little evidence of a meaningful benefit in the azithromycin plus usual care group in time to first reported recovery versus usual care alone (hazard ratio 1·08, 95% Bayesian credibility interval [BCI] 0·95 to 1·23), equating to an estimated benefit in median time to first recovery of 0·94 days (95% BCI −0·56 to 2·43). The probability that there was a clinically meaningful benefit of at least 1·5 days in time to recovery was 0·23. 16 (3%) of 500 participants in the azithromycin plus usual care group and 28 (3%) of 823 participants in the usual care alone group were hospitalised (absolute benefit in percentage 0·3%, 95% BCI −1·7 to 2·2). There were no deaths in either study group. Safety outcomes were similar in both groups. Two (1%) of 455 participants in the azothromycin plus usual care group and four (1%) of 668 participants in the usual care alone group reported admission to hospital during the trial, not related to COVID-19. Our findings do not justify the routine use of azithromycin for reducing time to recovery or risk of hospitalisation for people with suspected COVID-19 in the community. These findings have important antibiotic stewardship implications during this pandemic, as inappropriate use of antibiotics leads to increased antimicrobial resistance, and there is evidence that azithromycin use increased during the pandemic in the UK. UK Research and Innovation and UK Department of Health and Social Care.

The history of water in Mars The Mars Phoenix mission has sent back images of what — before it melted away — looked like water ice. Meanwhile our knowledge of the planet's distant watery past is being refined by the instruments on-board Mars Reconnaissance Orbiter. The presence of interlayered hydrated silicate (phyllosilicate) minerals on Mars preserves a record of past interactions between liquid water and rocks. The phyllosilicates are restricted to ancient terrains dating from the earliest geologic era of Mars, the Noachian, and previous data suggested that phyllosilicates existed within a relatively narrow range of mineralogy. The latest spectromety data from the Reconnaissance Orbiter are consistent with an ancient Noachian origin for the phyllosilicates — but point to a much more varied mineralogy indicative of active, pervasive hydrologic processes throughout the crust of early Mars, including the surface. Results from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) of phyllosilicate-rich regions are reported. It is discovered that stratigraphic relationships show olivine-rich materials overlying phyllosilicate-bearing units, indicating cessation of aqueous alteration before emplacement of the olivine-bearing unit. It is also found phyllosilicates in sedimentary deposits clearly laid by water, pointing to a rich diversity of Noachian environments conducive to habitability. Phyllosilicates, a class of hydrous mineral first definitively identified on Mars by the OMEGA (Observatoire pour la Mineralogie, L’Eau, les Glaces et l’Activitié) instrument 1 , 2 , preserve a record of the interaction of water with rocks on Mars. Global mapping showed that phyllosilicates are widespread but are apparently restricted to ancient terrains and a relatively narrow range of mineralogy (Fe/Mg and Al smectite clays). This was interpreted to indicate that phyllosilicate formation occurred during the Noachian (the earliest geological era of Mars), and that the conditions necessary for phyllosilicate formation (moderate to high pH and high water activity 3 ) were specific to surface environments during the earliest era of Mars’s history 4 . Here we report results from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) 4 of phyllosilicate-rich regions. We expand the diversity of phyllosilicate mineralogy with the identification of kaolinite, chlorite and illite or muscovite, and a new class of hydrated silicate (hydrated silica). We observe diverse Fe/Mg-OH phyllosilicates and find that smectites such as nontronite and saponite are the most common, but chlorites are also present in some locations. Stratigraphic relationships in the Nili Fossae region show olivine-rich materials overlying phyllosilicate-bearing units, indicating the cessation of aqueous alteration before emplacement of the olivine-bearing unit. Hundreds of detections of Fe/Mg phyllosilicate in rims, ejecta and central peaks of craters in the southern highland Noachian cratered terrain indicate excavation of altered crust from depth. We also find phyllosilicate in sedimentary deposits clearly laid by water. These results point to a rich diversity of Noachian environments conducive to habitability.

The swift fox Vulpes velox is generally associated with the short‐grass prairie ecosystem of the North American Great Plains; a system that has declined by approximately 50% over the last century. Yet, swift fox populations seem to demonstrate regional variation in trends, with some populations declining while others appear stable to increasing. In Wyoming, USA, swift foxes have been observed and successfully reproducing over 100 km west of their historical range boundary in shrubland‐dominated habitats, previously deemed unsuitable. This has created challenges in conservation, as it is unclear what factors are uniquely important to a species occupying habitats previously considered unsuitable. Therefore, we sought to investigate fundamental questions regarding swift fox ecology in this novel habitat: 1) what environmental gradients are contributing to suitable habitat?, 2) how is swift fox habitat suitability associated with competitors (American badgers Taxidea taxus and coyotes Canis latrans) in space?, and 3) how do swift foxes and competitors allocate activity in time? Between 2021 and 2023, seven swift foxes were GPS‐collared, and 71 camera traps were deployed in central Wyoming. GPS‐collar locations paired with environmental covariates were used to develop a habitat suitability model using Random Forest, predicting 30.28% of our study area was suitable. Important habitat resources identified were herbaceous biomass, shrub height, and sand content. We found swift foxes likely have minimal spatial and temporal separation between competitors, specifically coyotes. We hypothesize that swift foxes may successfully coexist with competitors either by being less risk‐averse for the sake of resource acquisition or by relying on abundant escape cover, which reduces the need to modulate spatial or temporal activity. Our findings enhance our understanding of environmental factors contributing to suitable habitats and how swift foxes coexist in time and space with competitors in a novel shrubland environment.