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•Background: Self-harm is a major public health challenge, and repeated self-harm is common in those attending hospital following an episode. Evidence suggests psychological interventions could help people who self-harm, but few definitive studies have assessed their clinical and cost-effectiveness. Repeated self-harm is associated with poor quality of life, depression, suicide and increased health service costs which justify the development of psychotherapeutic interventions tailored for people with repeated self-harm. •Methods: FReSH START is a multicentre individually 1:1 randomised controlled trial evaluating the clinical and cost-effectiveness of standard care plus psychological therapy or standard care alone for adults (≥ 18 years) presenting at an emergency department (ED) with repeated self-harm. Recruiting 630 participants, it includes an internal pilot, economic evaluation and process evaluation. The intervention will be delivered by mental health staff working in acute settings, with experience of assessing and managing risk in people presenting to emergency services with self-harm. Staff will be trained and supervised to deliver one of three specially adapted therapies: psychodynamic interpersonal therapy, cognitive behavioural therapy or acceptance and commitment therapy. Participants allocated to the intervention will receive one of the adapted therapies according to therapist allocation for up to 6 months via 12 weekly, one to one, 45–50-min sessions. The primary outcome is quality of life measured by the Clinical Outcomes in Routine Evaluation Outcome Measure at 12 months post-randomisation. Secondary outcomes include suicidal intent, depression and cost-effectiveness. Data are collected using hospital attendance records and online/postal/telephone questionnaires at 6 and 12 months post-randomisation, with resource use additionally collected at 3 and 9 months. •Discussion: This protocol outlines a randomised controlled trial to investigate whether mo

Urbanisation and climate change have increased the need for equitable access and visibility of urban green and blue spaces (GBS), to promote the sustainability and resilience of cities and to improve the well-being of their inhabitants. In this paper, we test an implementation of the newly proposed guideline to achieve equitable greening, the 3-30-300 rule, in three European cities: Paris Region (France), Aarhus Municipality (Denmark), and Grad Velika Gorica (Croatia). In this analysis, every residential building should have at least three viewable trees, 30% neighbourhood GBS cover, and a GBS of at least 1 hectare within 300 m. Our results show that none of the cities currently meet any of these three components, and the three cities differed in which rules were most closely met. In our implementation, substantial changes were needed in all cities to meet the guidelines: 12.6% of Paris, 10% of Aarhus, and 18.4% of Velika Gorica’s urban footprint were converted to grass or tree cover, with implications for >100,000 buildings and >900,000 inhabitants. Our study discusses how existing conditions in each city impacted the viability of meeting the rule and proposes key considerations for future implementations of such guidelines, drawing on examples of innovative GBS already implemented globally.

The first samples collected by the Mars 2020 mission represent units exposed on the Jezero Crater floor, from the potentially oldest Séítah formation outcrops to the potentially youngest rocks of the heavily cratered Máaz formation. Surface investigations reveal landscape-to-microscopic textural, mineralogical, and geochemical evidence for igneous lithologies, some possibly emplaced as lava flows. The samples contain major rock-forming minerals such as pyroxene, olivine, and feldspar, accessory minerals including oxides and phosphates, and evidence for various degrees of aqueous activity in the form of water-soluble salt, carbonate, sulfate, iron oxide, and iron silicate minerals. Following sample return, the compositions and ages of these variably altered igneous rocks are expected to reveal the geophysical and geochemical nature of the planet’s interior at the time of emplacement, characterize martian magmatism, and place timing constraints on geologic processes, both in Jezero Crater and more widely on Mars. Petrographic observations and geochemical analyses, coupled with geochronology of secondary minerals, can also reveal the timing of aqueous activity as well as constrain the chemical and physical conditions of the environments in which these minerals precipitated, and the nature and composition of organic compounds preserved in association with these phases. Returned samples from these units will help constrain the crater chronology of Mars and the global evolution of the planet’s interior, for understanding the processes that formed Jezero Crater floor units, and for constraining the style and duration of aqueous activity in Jezero Crater, past habitability, and cycling of organic elements in Jezero Crater.

The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater’s sedimentary delta, finding the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Fe-Mg carbonates along grain boundaries indicate reactions with CO2-rich water, under water-poor conditions. Overlying Séítah is a unit informally named Máaz, which we interpret as lava flows or the chemical complement to Séítah in a layered igneous body. Voids in these rocks contain sulfates and perchlorates, likely introduced by later near-surface brine evaporation. Core samples of these rocks were stored aboard Perseverance for potential return to Earth.

The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater's sedimentary delta, finding that the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Seitah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Magnesium-iron carbonates along grain boundaries indicate reactions with carbon dioxide-rich water under water-poor conditions. Overlying Seitah is a unit informally named Maaz, which we interpret as lava flows or the chemical complement to Seitah in a layered igneous body. Voids in these rocks contain sulfates and perchlorates, likely introduced by later near-surface brine evaporation. Core samples of these rocks have been stored aboard Perseverance for potential return to Earth.

Before the Perseverance rover landing, the acoustic environment of Mars was unknown. Models predicted that: (1) atmospheric turbulence changes at centimetre scales or smaller at the point where molecular viscosity converts kinetic energy into heat1, (2) the speed of sound varies at the surface with frequency2,3 and (3) high-frequency waves are strongly attenuated with distance in CO2 (refs. 2–4). However, theoretical models were uncertain because of a lack of experimental data at low pressure and the difficulty to characterize turbulence or attenuation in a closed environment. Here, using Perseverance microphone recordings, we present the first characterization of the acoustic environment on Mars and pressure fluctuations in the audible range and beyond, from 20 Hz to 50 kHz. We find that atmospheric sounds extend measurements of pressure variations down to 1,000 times smaller scales than ever observed before, showing a dissipative regime extending over five orders of magnitude in energy. Using point sources of sound (Ingenuity rotorcraft, laser-induced sparks), we highlight two distinct values for the speed of sound that are about 10 m s−1 apart below and above 240 Hz, a unique characteristic of low-pressure CO2-dominated atmosphere. We also provide the acoustic attenuation with distance above 2 kHz, allowing us to explain the large contribution of the CO2 vibrational relaxation in the audible range. These results establish a ground truth for the modelling of acoustic processes, which is critical for studies in atmospheres such as those of Mars and Venus.

Observations from orbital spacecraft have shown that Jezero crater, Mars, contains a prominent fan-shaped body of sedimentary rock deposited at its western margin. The Perseverance rover landed in Jezero crater in February 2021. We analyze images taken by the rover in the three months after landing. The fan has outcrop faces that were invisible from orbit, which record the hydrological evolution of Jezero crater. We interpret the presence of inclined strata in these outcrops as evidence of deltas that advanced into a lake. In contrast, the uppermost fan strata are composed of boulder conglomerates, which imply deposition by episodic high-energy floods. This sedimentary succession indicates a transition, from a sustained hydrologic activity in a persistent lake environment, to highly energetic short-duration fluvial flows.

A central objective of the NASA Mars 2020 Perseverance rover mission is to collect and document a suite of scientifically compelling samples for possible return to Earth by a subsequent mission [1]. Strategic planning by the Mars 2020 Science Team has thus far identified a set of notional sample caches. These arose from integrating the testable hypotheses that could be addressed by Mars 2020 within the framework of the geology of Jezero crater and its surroundings [2], identifying specific locations of high scientific interest by analysis of remotely sensed data, and traversability considerations [1]. Here we describe the general characteristics of the identified notional caches and compare them to the types of samples previously prioritized by the wider Mars science community [3]. While strategic planning will guide and streamline the decision-making processes once the rover lands at Jezero crater, the actual samples collected will depend on the landing location, the traverse taken, and decisions made by the Mars 2020 Science Team.

The Mars 2020 team plans to explore and collect samples from diverse ancient environments preserved in the rocks in and around Jezero Crater. Here, we offer a tour of diverse, ancient habitable environments planned for exploration and sampling.

An expanded sedimentary section provides an opportunity to elucidate conditions in the nascent Chicxulub crater during the hours to millennia after the Cretaceous‐Paleogene (K‐Pg) boundary impact. The sediments were deposited by tsunami followed by seiche waves as energy in the crater declined, culminating in a thin hemipelagic marlstone unit that contains atmospheric fallout. Seiche deposits are predominantly composed of calcite formed by decarbonation of the target limestone during impact followed by carbonation in the water column. Temperatures recorded by clumped isotopes of these carbonates are in excess of 70°C, with heat likely derived from the central impact melt pool. Yet, despite the turbidity and heat, waters within the nascent crater basin soon became a viable habitat for a remarkably diverse cross section of the food chain. The earliest seiche layers deposited with days or weeks of the impact contain earliest Danian nannoplankton and dinocyst survivors. The hemipelagic marlstone representing the subsequent years to a few millennia contains a nearly monogeneric calcareous dinoflagellate resting cyst assemblage suggesting deteriorating environmental conditions, with one interpretation involving low light levels in the impact aftermath. At the same horizon, microbial fossils indicate a thriving bacterial community and unique phosphatic fossils including appendages of pelagic crustaceans, coprolites andbacteria‐tunneled fish bone, suggesting that this rapid recovery of the base of the food chain may have supported the survival of larger, higher trophic‐level organisms. The extraordinarily diverse fossil assemblage indicates that the crater was a unique habitat in the immediate impact aftermath, possibly as aresult of heat and nutrients supplied by hydrothermal activity.

Cambrian siliciclastic sequences along the Dead Sea Transform (DST) margin in southern Israel and southern Jordan host both detrital fluorapatite [D‐apatite] and U‐rich authigenic carbonate‐fluorapatite (francolite) [A‐apatite]. D‐apatite and underlying Neoproterozoic basement apatite yield fission‐track (FT) data reflecting Palaeozoic–Mesozoic sedimentary cycles and epeirogenic events, and dispersed (U–Th–Sm)/He (AHe) ages. A‐apatite, which may partially or completely replace D‐apatite, yields an early Miocene FT age suggesting formation by fracturing, hydrothermal fluid ascent and intra‐strata recrystallisation, linked to early DST motion. The DST, separating the African and Arabian plates, records ~105 km of sinistral strike‐slip displacement, but became more transtensional post‐5 Ma. Helium diffusion measurements on A‐apatite are consistent with thermally activated volume diffusion, indicating Tc ~52 to 56 ± 10°C (cooling rate 10°C/Ma). A‐apatite AHe data record Pliocene cooling (~35 to 40°C) during the transtensional phase of movement. This suggests that timing of important milestones in DST motion can be discerned using A‐apatite low‐temperature thermochronology data alone.

Defying common expectations, some of the oldest landscapes on Earth are found in the humid tropics. 40Ar/39Ar dating shows that Fe-rich regolith that armors the ∼700–1000 m elevation banded iron-formation plateaus at Urucum, Mato Grosso do Sul, Brazil, results from chemical weathering that began at least 70 million years ago. Cosmogenic 3He concentrations in residual hematite clasts and the underlying saprolite on one plateau imply an extraordinarily slow surface lowering rate of 0.07–0.10 m Ma−1 maintained over the last ∼17–70 Ma. Cosmogenic 10Be and 26Al concentrations in a quartz vein in the same plateau suggest a similarly low surface erosion rate of ∼0.11–0.18 m Ma−1 over the past few million years. Cosmogenic 3He concentrations in goethite cementing a ∼200 m elevation indurated pediment ∼3 km northwest of the plateau escarpment yields a minimum exposure age of ∼2.6 Ma, revealing that some of the low-lying areas had already been incised and locally stabilized by goethite cementation by then. In contrast, 36Cl measurements on limestone outcrops at ∼170 m elevation and ∼6.5 km northwest of the Urucum plateau reveal short-term erosion rates of 7.1 ± 0.4 and 10.1 ± 0.5 m Ma−1, showing that areas not stabilized by goethite cementation are undergoing erosion at a relatively fast pace. The ∼700 m of relief at Urucum is consistent with differential denudation over ∼70 Ma controlled by lithological differences in chemical and physical rates of weathering and erosion. Effective chemical weathering and protracted low rates of erosion for the high-elevation surface result in armoring by a resilient residue of hematite blocks that are relatively insoluble and too heavy to transport. Armoring by the surface lag of large chemically resilient hematite blocks and bedded hematite saprolite focuses meteoric water flow into the subsurface and along faults. Preferential subsurface flow along the permeable pathways between insoluble hematite blocks, combined with segmentation of the

The Atacama Desert of northern Chile hosts many of the world's largest porphyry copper deposits (PCDs), many of which have been upgraded through supergene enrichment (Sillitoe and McKee 1996). Enrichment of exhumed PCDs occurs in the near-surface weathering environment, when copper is leached from primary sulphides and reprecipitated beneath the water table to form a concentrated blanket of secondary copper minerals (e.g. chalcocite). The Atacama is one of the driest regions on Earth, but supergene enrichment requires precipitation to drive the aqueous redistribution of metals. Previous alunite dating studies have suggested enrichment stopped in the middle Miocene, due to an increase in aridity. This conclusion is supported by the youngest supergene alunite ages from several PCDs clustering around 14 Ma (Sillitoe 2005). Hematite also forms in the leached caps of PCDs and hematite (U-Th)/He geochronology provides a tool to track the downward progression of weathering fronts (e.g. Cooper et al. 2016). This study will combine Ar-40/Ar-39 dating of supergene alunite (a proxy for the timing of copper enrichment) with hematite geochronology (as an indicator of the progression of weathering) to better understand the link between water table movement and supergene enrichment of Central Andean PCDs.