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Over the Nullarbor Plain in South Australia, the Desert Fireball Network detected a fireball on the night of June 1, 2019 (7:30 pm local time), and 6 weeks later recovered a single meteorite (42 g) named Arpu Kuilpu. This meteorite was then distributed to a consortium of collaborating institutions to be measured and analyzed by a number of methodologies including SEM‐EDS, EPMA, ICP‐MS, gamma‐ray spectrometry, ideal gas pycnometry, magnetic susceptibility measurement, μCT, optical microscopy, and accelerator and noble gas mass spectrometry techniques. These analyses revealed that Arpu Kuilpu is an unbrecciated H5 ordinary chondrite, with minimal weathering (W0‐1) and minimal shock (S2). The olivine and pyroxene mineral compositions (in mole%) are Fa: 19.2 ± 0.2 and Fs: 16.8 ± 0.2, further supporting the H5 type and class. The measured oxygen isotopes are also consistent with an H chondrite (δ17O‰ = 2.904 ± 0.177; δ18O‰ = 4.163 ± 0.336; Δ17O‰ = 0.740 ± 0.002). Ideal gas pycnometry measured bulk and grain densities of 3.66 ± 0.02 and 3.77 ± 0.02 g cm−3, respectively, yielding a porosity of 3.0% ± 0.7. The magnetic susceptibility of this meteorite is log χ = 5.16 ± 0.08. The most recent impact‐related heating event experienced by Arpu Kuilpu was measured by 40Ar/39Ar chronology to be 4467 ± 16 Ma, while the cosmic ray exposure age is estimated to be between 6 and 8 Ma. The noble gas isotopes, radionuclides, and fireball observations all indicate that Arpu Kuilpu's meteoroid was quite small (maximum radius of 10 cm, though more likely between 1 and 5 cm). Although this meteorite is a rather ordinary ordinary chondrite, its prior orbit resembled that of a Jupiter Family Comet (JFC) further lending support to the assertion that many cm‐ to m‐sized objects on JFC orbits are asteroidal rather than cometary in origin. [ABSTRACT FROM AUTHOR]

Summary: Backgrounds and Aims: Alcohol use leads to disabilities and deaths worldwide. It not only harms the liver but also causes alcohol use disorder (AUD) and heart disease. Additionally, alcohol consumption contributes to health disparities among different socio‐economic groups. Methods: We estimated global and regional trends in the burden of AUD, liver disease, and cardiovascular disease from alcohol using the methodology of the Global Burden of Disease study. Results: In 2019, the highest disability‐adjusted life years rate per 100,000 population was due to AUD (207.31 [95% Uncertainty interval (UI) 163.71–261.66]), followed by alcohol‐associated liver disease (ALD) (133.31 [95% UI 112.68–156.17]). The prevalence rate decreased for AUD (APC [annual percentage change] −0.38%) and alcohol‐induced cardiomyopathy (APC −1.85%) but increased for ALD (APC 0.44%) and liver cancer (APC 0.53%). Although the mortality rate for liver cancer from alcohol increased (APC 0.30%), mortality rates from other diseases decreased. Between 2010 and 2019, the burden of alcohol‐associated complications increased in countries with low and low‐middle sociodemographic index (SDI), contributing more significantly to the global burden. Conclusion: The global burden of AUD, liver, and cardiovascular disease has been high and increasing over the past decade, particularly for liver complications. Lower SDI countries are contributing more to this global burden. There is a pressing need for effective strategies to address this escalating burden. [ABSTRACT FROM AUTHOR]

Dating young lunar surfaces, such as impact ejecta blankets and terrains associated with recent volcanic activities, provides critical information on the recent events that shaped the surface of the Moon. Model age derivation of young or small areas using a crater chronology is typically achieved through manual counting, which requires a lot of small impact craters to be tediously mapped. In this study, we present the use of a Crater Detection Algorithm (CDA) to extract crater populations on Lunar Reconnaissance Orbiter—Narrow Angle Camera (LRO‐NAC) and Kaguya Terrain Camera images. We applied our algorithm to images covering the ejecta blankets of four Copernican impact craters and across four young mare terrains, where manually derived model ages were already published. Across the eight areas, 10 model ages were derived. We assessed the reproducibility of our model using two populations for each site: (a) an unprocessed population and (b) a population adjusted to remove contaminations of secondary and buried craters. The results showed that unprocessed detections led to overestimating crater densities by 12%–48%, but "adjusted" populations produced consistent results within <20% of published values in 80% of cases. Regarding the discrepancies observed, we found no significant error in our detections that could explain the differences with crater densities manually measured. With careful processing, we conclude that a CDA can be used to determine model ages and crater densities for the Moon. We also emphasize that automated crater datasets need to be processed, interpreted and used carefully, in unity with geologic reasoning. The presented approach can offer a consistent and reproducible way to derive model ages. Plain Language Summary: Studying young lunar surfaces, such as impacted areas or volcanic activity, helps us understand recent events that have shaped the Moon's surface. Determining the model age of these areas generally involves manually counting small craters, which is time‐consuming and variable. This study presents a machine‐learning approach to detect craters on images acquired by the Lunar Reconnaissance Orbiter‐Narrow Angle Camera and the Kaguya Terrain Camera. Four impact craters and four young mare terrains were analyzed, where model ages had already been determined manually. When comparing our automatic counts to the manual counts, we observed that our results became more consistent with the published surface ages when we excluded secondary or buried craters from our crater populations. We also outline that automatic crater detection methods can be used to determine the age of lunar surfaces in a reliable and consistent manner when used correctly. Key Points: Automatic crater counting of the Moon was achieved using a Convolutional Neural Network architecture and applied to LRO‐NAC and Kaguya Terrain Camera imagesTesting of the automatic counts against manual counts across the same count areas is required to provide confidence in the resultsSurface ages resulting from automatic crater counts are within acceptable error of model ages for the same area found using manual counts [ABSTRACT FROM AUTHOR]

Evidence of impact‐induced compaction in the carbonaceous chondrites, specifically CMs and CVs, has been widely investigated utilizing microscopy techniques and impact experiments. Here, we use high‐resolution photography and large area and high‐resolution electron backscattered diffraction (EBSD) mapping analyses in tandem, to explore the effects of impact‐induced compaction at both the meso‐ and micro‐scales in the Allende CV3.6 carbonaceous chondrite. Macro‐scale photography images of a ~25 cm slab of Allende captured meso‐scale features including calcium‐aluminum inclusions (CAIs) and chondrules. CAIs have a long‐axis shape‐preferred orientation (SPO). Examination of such meso‐scale features in thin section revealed the same trend. Matrix grains from this section display a large amount of heterogeneity in petrofabric orientation; microscale, high‐resolution, large area EBSD mapping of ~300,000 olivine matrix grains; high‐resolution large area EBSD map across an elongate CAI; and a series of high‐resolution EBSD maps around two chondrules and around the CAI revealed crystallographic preferred orientations (CPOs) in different directions. Finally, internal grains of the CAI were found to demonstrate a weak lineation CPO, the first crystallographic detection of possible CAI "flow." All results are consistent with multiple, gentle impacts on the Allende parent body causing hemispheric compaction. The larger, more resistant components are likely to have been compressed and oriented by earlier impacts, and the matrix region petrofabrics and CAI "flow" likely occurred during subsequent impacts. Meteoritic components respond differently to impact events, and consequently, it is likely that different components would retain evidence of different impact events and angles. [ABSTRACT FROM AUTHOR]

Objectives: Prevalence of malnutrition among ambulatory inflammatory bowel disease (IBD) patients in Singapore is unknown. We aimed to evaluate the prevalence of ambulatory IBD patients at risk of malnutrition (ARMN) using Malnutrition Universal Screening Tool (MUST) and its clinical outcomes. Methods: IBD patients were recruited from March to June 2018 and followed up for 6 months. ARMN patients were defined as having a MUST score of 2 or more compared with those not at risk (non‐ARMN). Results: Altogether 217 patients were recruited, including 128 (59.0%) with ulcerative colitis (UC) and 89 (41.0%) with Crohn's disease (CD). The mean body mass index (BMI) was 23.5 ± 4.5 kg/m2; 35 (16.1%) patients were on biologics, and 52 (24.0%) were on steroids. Among them 25 (11.5%) patients were ARMN, with a predominance of UC (n = 15, 60.0%). The majority of ARMN patients were underweight (n = 23, 92.0%) while 114 (59.4%) non‐ARMN patients were overweight. ARMN patients had a significantly lower albumin (38.3 g/L vs 41.9 g/L) and a significantly increased proportion of patients with C‐reactive protein ≥5 mg/L (36.0% vs 19.3%). There was a trend towards longer hospital stay among ARMN patients, although this was not statistically significant. Use of biologics or immunomodulators and albumin levels were associated with being ARMN. Conclusion: Using MUST, 11.5% of our ambulatory IBD patients in Singapore were identified to be ARMN. Among ARMN patients, a trend was demonstrated towards a longer hospital stays for admitted patients. This underscores the need to actively screen ambulatory IBD patients for malnutrition. [ABSTRACT FROM AUTHOR]

On June 19, 2020 at 20:05:07 UTC, a fireball lasting 5.5s was observed above Western Australia by three Desert Fireball Network observatories. The meteoroid entered the atmosphere with a speed of 14.00±0.17 km s‐1 and followed a 58° slope trajectory from a height of 75 km down to 18.6 km. Despite the poor angle of triangulated planes between observatories (29°) and the large distance from the observatories, a well‐constrained kilo‐size main mass was predicted to have fallen just south of Madura in Western Australia. However, the search area was predicted to be large due to the trajectory uncertainties. Fortunately, the rock was rapidly recovered along the access track during a reconnaissance trip. The 1.072 kg meteorite called Madura Cave was classified as an L5 ordinary chondrite. The calculated orbit is of Aten type (mostly contained within the Earth's orbit), only the second time a meteorite was observed on such an orbit, after Bunburra Rockhole. Dynamical modeling shows that Madura Cave has been in near‐Earth space for a very long time. The dynamical lifetime in near‐Earth space for the progenitor meteoroid is predicted to be ~87 Myr. This peculiar orbit also points to a delivery from the main asteroid belt via the ν6 resonance, and therefore an origin in the inner belt. This result contributes to drawing a picture for the existence of a present‐day L chondrite parent body in the inner belt. [ABSTRACT FROM AUTHOR]

Impact craters are the most common feature on the Moon's surface. Crater size–frequency distributions provide critical insight into the timing of geological events, surface erosion rates, and impact fluxes. The impact crater size–frequency follows a power law (meter‐sized craters are a few orders of magnitude more numerous than kilometric ones), making it tedious to manually measure all the craters within an area to the smallest sizes. We can bridge this gap by using a machine learning algorithm. We adapted a Crater Detection Algorithm to work on the highest resolution lunar image data set (Lunar Reconnaissance Orbiter‐Narrow‐Angle Camera [NAC] images). We describe the retraining and application of the detection model to preprocessed NAC images and discussed the accuracy of the resulting crater detections. We evaluated the model by assessing the results across six NAC images, each covering a different lunar area at differing lighting conditions. We present the model's average true positive rate for small impact craters (down to 20 m in diameter) is 93%. The model does display a 15% overestimation in calculated crater diameters. The presented crater detection model shows acceptable performance on NAC images with incidence angles ranging between ∼50° and ∼70° and can be applied to many lunar sites independent to morphology. Plain Language Summary: The Moon's surface is covered in impact craters and recording their spatial density gives researchers the ability to study the geological evolution of our satellite. Analyzing craters helps in determining the physical properties of planetary surfaces and how/if impact rates change over time. These analyses rely on recording spatial densities for numerous surfaces, which has been achieved for craters >1–2 km on the Moon. Manually counting the smaller craters, which number in the hundreds of millions, is a daunting task. We adapted a Crater Detection Algorithm and applied it to the highest resolution lunar imagery data set. We describe our method for gathering, reformatting, and detecting craters across lunar images down to 20 m in diameter. The detection model performance was quantitatively evaluated across six different regions, each with different terrain and lighting conditions. Comparison between manually mapped craters and detections from our model allows us to conclude that the model has an acceptable performance in detecting fresh to moderately degraded craters of all sizes, down to 20 m in diameter, when compared to other studies. Automated crater detection complements manual counting methods and aids in unlocking secrets of the Moon's surface. Key Points: Adapted and retrained a Crater Detection Algorithm (using YOLOv3) to work on high‐resolution Lunar Reconnaissance Orbiter‐Narrow‐Angle Camera (NAC) imagesDeveloped a workflow for georeferencing and detecting craters down to 10 pixels in diameter across multiple overlapping NAC imagesEvaluation reveals acceptable performance in detecting craters on diverse terrains, across images with 50–70° incidence angles [ABSTRACT FROM AUTHOR]

The Martian nakhlite meteorites, which represent multiple events that belong to a single magma source region represent a key opportunity to study the evolution of Martian petrogenesis. Here 16 of the 26 identified nakhlite specimens are studied using coupled electron backscatter diffraction (EBSD) and emplacement end‐member calculations. EBSD was used to determine shape preferred orientation of contained augite (high Ca‐clinopyroxene) phenocrysts by considering their crystallographic preferred orientation (CPO). Parameters derived from EBSD, and energy dispersive X‐ray spectroscopy spectra were used in basic emplacement models to assess their dominant mechanism against three end‐member scenarios: thermal diffusion, crystal settling, and crystal convection. Results from CPO analyses indicate low intensity weak‐moderate CPO. In all samples, a consistent foliation within the <001> axes of augite are observed typically coupled with a weaker lineation CPO in one of the other crystallographic axes. These CPO results agree best with crystal settling being the dominant emplacement mechanism for the nakhlites. Modeled crystal settling results identify two distinguishable groups outside of the model's resolution indicating the presence of secondary emplacement mechanisms. Comparison of the two identified groups against CPO, geochemical, and age parameters indicate random variability between individual meteorites. Therefore, coupled CPO and emplacement modeling results identify an overarching characteristic of a dominant crystal settling emplacement mechanism for the nakhlite source volcano despite exhibiting random variation with each discharge through time. Plain Language Summary: A group of Martian meteorites known as the nakhlites was investigated to better understand volcanism on Mars by using the specialist microscopy technique of electron backscatter diffraction and basic modeling of known igneous processes. The presented data suggest that the magma that was discharged from the nakhlite source volcano varied randomly through time but solidified into rocks via a consistent dominant mechanism of crystal settling. These findings show Martian volcanism is dynamic, where individual eruptions are variable, yet retain overarching volcanic source characteristics that can be identified from large studies of multiple samples. Key Points: S‐type to LS‐type crystallographic preferred orientation (CPO) identified in the nakhlitesCPO indicate nakhlite formation in environments characteristic of crystal settlingCPO and emplacement modeling suggest random variation in discharge through time with overarching consistent emplacement [ABSTRACT FROM AUTHOR]

Deformation is a near ubiquitous process that is observed within nearly all naturally forming rocks. Electron backscatter diffraction (EBSD) is a technique that enables slip‐systems (a form of plastic deformation) to be inferred from intracrystalline misorientations at a comparable scale to the representative CPO analysis (≥300 crystals for the nakhlites). Extensive laboratory and studies on naturally occurring samples have identified preferential mantle condition extrinsic parameters for specific slip‐system signatures within olivine and clinopyroxene. Intracrystalline misorientation patterns for olivine and augite (high Ca‐clinopyroxene) for 16 different Martian nakhlite meteorites (21 sections) were analyzed and assessed against these known parameters. Investigation of high and low deformation regions within the nakhlites revealed a shift in intracrystalline misorientation patterns for 10 of the 21 sections. Interpreted as both shock (high deformations) and emplacement (low deformation) signatures, the observed variations in deformation patterns for the two main regimes of deformation indicate heterogeneous sampling of the nakhlite source crater. Our findings indicate that shock deformation is prevalent throughout the nakhlites, and that great care needs to be taken when interpreting intracrystalline misorientations of crystals within apparent lower deformation regions. Plain Language Summary: Clinopyroxene and olivine are important minerals for studying igneous processes on Mars and Earth (from the surface to the upper mantle). Here, clinopyroxene and olivine intracrystalline misorientation patterns—deformational movement within a crystal—were investigated in a group of meteorites from Mars using the specialist microscopic technique of electron backscatter diffraction (EBSD). The nakhlites are mafic rocks representing the largest collection of rocks from a singular—but as yet unknown—location on Mars. Combined intracrystalline misorientation patterns for both olivine and clinopyroxene reveal nine different shock deformation signatures for the nakhlites indicating that they were sourced from multiple locations within the ejection crater. Nonshock related deformation can also be observed but tends to be masked by the dominance of shock deformation features even in low deformation regions. Key Points: Electron backscatter diffraction reveals shock‐derived deformation to mask nonshock deformation even in low deformation regions in the nakhlitesIntracrystalline misorientation patterns indicate nine distinct derived deformation signatures for 16 nakhlitesIntracrystalline misorientation patterns are identified within low deformation regions interpreted as emplacement deformation [ABSTRACT FROM AUTHOR]

Martian meteorites are rare; therefore, the discovery of new meteorites has the potential to significantly expand our current understanding of Mars. In this study, we describe four new shergottites, all found within the past 5 yr, in Northwest Africa (NWA): NWA 10441, NWA 10818, NWA 11043, and NWA 12335. To determine the geochemical and mineralogical composition of these new shergottites, a number of traditional and nontraditional analytical techniques were utilized, such as high‐resolution X‐ray computed tomography (for 3‐D modal abundance determination) and electron backscattered diffraction (for identification of shock features). This enabled a comprehensive, nondestructive investigation of the in situ and bulk characteristics of these meteorites. From the results, we confirm the preliminary classifications of NWA 10441 and NWA 12335 as basaltic (diabasic), and NWA 10818 and NWA 11043 as poikilitic, shergottites. Chondrite‐normalized rare earth element (REE) patterns of shergottites distinguish likely source reservoirs in the Martian mantle. NWA 10441 and NWA 12335 have bulk enriched REE patterns. NWA 10818 has an intermediate REE pattern, being slightly depleted in the light REE. Although published data for bulk rock REE in NWA 11043 indicate an enriched pattern, here we show that targeted in situ analyses of unaltered minerals reveal an intermediate REE pattern, suggesting that terrestrial weathering combined with shock processes experienced by these meteorites on ejection may affect the bulk analysis. Extensive fracturing in NWA 11043 likely acted as conduits for terrestrial alteration products. We suggest that in situ spot checking of REE in meteorites will constrain any weathering effect on the REE pattern of the bulk rock. [ABSTRACT FROM AUTHOR]

On June 1, 2019, just before 7:30 p.m. local time, the Desert Fireball Network (DFN) detected a −9.3 magnitude fireball over South Australia near the Western Australia border. The event was observed by six fireball observatories, and lasted for 5 s. One station was nearly directly underneath the trajectory, greatly constraining the trajectory solution. This trajectory's backward numerical integrations indicate that the object originated from the outer main belt with a semimajor axis of 2.75 au. A light curve was also extracted and showed that the body experienced very little fragmentation during its atmospheric passage. A search campaign was conducted with several DFN team members and other volunteers. One 42 g fragment was recovered within the predicted fall area based on the dark flight model. Based on measurements of short‐lived radionuclides, the fragment was confirmed to be a fresh fall. The meteorite, Arpu Kuilpu, has been classified as an H5 ordinary chondrite. This marks the fifth fall recovered in Australia by the DFN, and the smallest meteoroid (≃2 kg) to ever survive entry and be recovered as a meteorite. [ABSTRACT FROM AUTHOR]

Hydrous phyllosilicate minerals, including the serpentine subgroup, are likely to be major constituents of material that will be bought back to Earth by missions to Mars and to primitive asteroids Ryugu and Bennu. Small quantities (< 60 g) of micrometre‐sized, internally heterogeneous material will be available for study, requiring minimally destructive techniques. Many conventional methods are unsuitable for phyllosilicates as they are typically finely crystalline and electron beam‐sensitive resulting in amorphisation and dehydration. New tools will be required for nanoscale characterisation of these precious extra‐terrestrial samples. Here we test the effectiveness of atom probe tomography (APT) for this purpose. Using lizardite from the Ronda peridotite, Spain, as a terrestrial analogue, we outline an effective analytical protocol to extract nanoscale chemical and structural measurements of phyllosilicates. The potential of APT is demonstrated by the unexpected finding that the Ronda lizardite contains SiO‐rich nanophases, consistent with opaline silica that formed as a by‐product of the serpentinisation of olivine. Our new APT approach unlocks previously unobservable nanominerals and nanostructures within phyllosilicates owing to resolution limitations of more established imaging techniques. APT will provide unique insights into the processes and products of water/rock interaction on Earth, Mars and primitive asteroids. [ABSTRACT FROM AUTHOR]

The cyclohepta[b]indole scaffold constitutes a salient structural motif in natural products as well as in men‐made pharmaceutically active ingredients. Cyclohepta[b]indoles consist of an indole nucleus fused to a seven‐membered carbacycle. Interest in cyclohepta[b]indole chemistry originates from natural product chemistry and medicinal chemistry. The chemistry of cyclohepta[b]indole‐based organic functional materials may be a research area with some potential. The state of the art of cyclohepta[b]indoloid chemism has been comprehensively and scholarly summarized by the leading review article of Stempel and Gaich in 2016. Following this lead, our Minireview covers the literature from 2016 to 2021. [ABSTRACT FROM AUTHOR]

Asteroid 4 Vesta is the only largely preserved differentiated asteroid and thus is an excellent proxy to study early magmatism occurring on planets and moons. In this study, we focus on eucrite Pecora Escarpment (PCA) 82502, a medium‐ to fine‐grained eucrite which chemical analyses suggest belongs to the main howardite–eucrite–diogenite clan, albeit with some peculiarities. We carried out backscattered electron and electron backscattered diffraction microscopy analyses of the meteorite along with step‐heating 40Ar/39Ar dating analyses of various types of groundmass aliquots. We show that Pecora Escarpment 82502 is composed of medium‐grained igneous crystalline clasts and smaller fractured satellite clasts surrounded by approximately 50 µm wide impact melt veins of the same composition. Our results show that the large crystalline clasts and fine‐grained veins both display little evidence of shock processes. Six groundmass aliquots from large crystalline clasts returned concordant plateau (>70% of 39Ar) or mini‐plateau (50–70% of 39Ar) 40Ar/39Ar ages with a weighted mean of 4531 ± 6 Ma (P = 0.67). Thermodynamic cooling and 40Ar diffusion models suggest that the K/Ar system recorded and preserved the igneous age despite subsequent infiltration of hot and quickly quenched melt veins. Our new igneous age, combined with evidence for four other young volcanic and plutonic eucrites of similar age, shows that Vesta was still magmatically active around 4531 Ma. The lack of younger ages suggests that this age might well represent the end of the magmatic activity in the upper crust of Vesta. When combined with existing paleomagnetic constraints, our data suggest that 4 Vesta had an active dynamo that was still active ~35 Ma after accretion. [ABSTRACT FROM AUTHOR]

Murrili, the third meteorite recovered by the Desert Fireball Network, is analyzed using mineralogy, oxygen isotopes, bulk chemistry, physical properties, noble gases, and cosmogenic radionuclides. The modal mineralogy, bulk chemistry, magnetic susceptibility, physical properties, and oxygen isotopes of Murrili point to it being an H5 ordinary chondrite. It is heterogeneously shocked (S2–S5), depending on the method used to determine it, although Murrili is not obviously brecciated in texture. Cosmogenic radionuclides yield a cosmic ray exposure age of 6–8 Ma, and a pre‐atmospheric meteoroid size of 15–20 cm in radius. Murrili's fall and subsequent month‐long embedment into the salt lake Kati Thanda significantly altered the whole rock, evident in its Mössbauer spectra, and visual inspection of cut sections. Murrili may have experienced minor, but subsequent, impacts after its formation 4475.3 ± 2.3 Ma, which left it heterogeneously shocked. [ABSTRACT FROM AUTHOR]

Determining when an impact crater formed is a complex and tedious task. However, this knowledge is crucial to understanding the geological history of planetary bodies and, more specifically, gives information on erosion rate measurements, meteorite ejection location, impact flux evolution and the loss of a magnetic field. The derivation of an individual crater's age is currently performed through manual counting. Because crater size scales as a power law, this method is limited to small (and/or young) surface areas and, in the case of the derivation of crater emplacement age, to a small set of impact craters. Here, we used a Crater Detection Algorithm, specifically retrained to detect small impact craters on large‐ and high‐resolution imagery data set to solve this issue. We applied it to a global, 5 m/pixel resolution mosaic of Mars. Here, we test the use of this data set to date 10 large impact craters. We developed a cluster analysis tool in order to distinguish potential secondary crater clusters from the primary crater population. We then use this, filtered, crater population to date each large impact crater and evaluate our results against literature ages. We found that automated counting filtered through clustering analysis produced similar model ages to manual counts. This technique can now be expanded to much wider crater dating surveys, and by extension to any other kind of Martian surface. We anticipate that this new tool will considerably expand our knowledge of the geological events that have shaped the surface of Mars, their timing and duration. Plain Language Summary: The age of an impact crater on a planetary surface is a crucial constraint in determining erosion rate, the crater source of Martian meteorites and the impact cratering flux evolution. This kind of measurement requires the counting of many impact craters superposed on the ejecta blanket of the considered crater and is therefore limited by human capability. To solve this issue, we adapted an automatic tool to detect small impact craters on the surface of Mars. We also developed an automatic approach to identify and remove clusters of small likely secondary craters detected by our algorithm. We assume these clusters of craters are formed by fragments ejected by an impact that formed a primary crater and need to be removed from crater densities used for age derivations. We applied our technique on 10 large Martian impact craters whose the formation age has been derived using manual counts and reported in the literature. We compared these ages to ours, derived from automatic count and automatic secondary craters filtering. Our results are consistent and indistinguishable from an age inferred from a manual count. For the first time, we demonstrate that an automated approach can deliver geologically meaningful model ages. Key Points: Automatic detection of small craters on ejecta blanket of 10 large Martian cratersIdentification of secondary craters through cluster analysisModel ages from our semi‐automatic approach are similar from manual counts [ABSTRACT FROM AUTHOR]

We present a novel methodology for recovering meteorite falls observed and constrained by fireball networks, using drones and machine learning algorithms. This approach uses images of the local terrain for a given fall site to train an artificial neural network, designed to detect meteorite candidates. We have field tested our methodology to show a meteorite detection rate between 75% and 97%, while also providing an efficient mechanism to eliminate false positives. Our tests at a number of locations within Western Australia also showcase the ability for this training scheme to generalize a model to learn localized terrain features. Our model training approach was also able to correctly identify three meteorites in their native fall sites that were found using traditional searching techniques. Our methodology will be used to recover meteorite falls in a wide range of locations within globe‐spanning fireball networks. [ABSTRACT FROM AUTHOR]

We report on the implementation of the concept of a photochemically elicited two‐carbon homologation of a π‐donor–π‐acceptor substituted chromophore by triple‐bond insertion. Implementing a phenyl connector between the slide‐in module and the chromophore enabled the synthesis of cylohepta[b]indole‐type building blocks by a metal‐free annulative one‐pot two‐carbon ring expansion of the five‐membered chromophore. Post‐irradiative structural elaboration provided founding members of the indolo[2,3‐d]tropone family of compounds. Control experiments in combination with computational chemistry on this multibond reorganization process founded the basis for a mechanistic hypothesis. [ABSTRACT FROM AUTHOR]

On November 27, 2015, at 10:43:45.526 UTC, a fireball was observed across South Australia by 10 Desert Fireball Network observatories lasting 6.1 s. An ~37 kg meteoroid entered the atmosphere with a speed of 13.68 ± 0.09 km s−1 and was observed ablating from a height of 85 km down to 18 km, having slowed to 3.28 ± 0.21 km s−1. Despite the relatively steep 68.5° trajectory, strong atmospheric winds significantly influenced the darkflight phase and the predicted fall line, but the analysis put the fall site in the center of Kati Thanda–Lake Eyre South. Kati Thanda has meters‐deep mud under its salt‐encrusted surface. Reconnaissance of the area where the meteorite landed from a low‐flying aircraft revealed a 60 cm circular feature in the muddy lake, less than 50 m from the predicted fall line. After a short search, which again employed light aircraft, the meteorite was recovered on December 31, 2015 from a depth of 42 cm. Murrili is the first recovered observed fall by the digital Desert Fireball Network (DFN). In addition to its scientific value, connecting composition to solar system context via orbital data, the recovery demonstrates and validates the capabilities of the DFN, with its next generation remote observatories and automated data reduction pipeline. [ABSTRACT FROM AUTHOR]

Impact craters on solar system bodies are used to determine the relative ages of surfaces. The smaller the limiting primary crater size, the higher the spatial resolution in surface/resurfacing age dating. A manually counted database (Robbins & Hynek, 2012, https://doi.org/10.1029/2011JE003966) of >384,000 craters on Mars >1 km in diameter exists. But because crater size scales as a power law, the number of impact craters in the size range 10 m to 1 km is in the tens of millions, a number making precise analysis of local variations of age, over an entire surface, impossible to perform by manual counting. To decode this crater size population at a planetary scale, we developed an automated Crater Detection Algorithm based on the You Only Look Once v3 object detection system. The algorithm was trained by annotating images of the controlled Thermal Emission Imaging System daytime infrared data set. This training data set contains 7,048 craters that the algorithm used as a learning benchmark. The results were validated against the manually counted database as the ground truth data set. We applied our algorithm to the Thermal Emission Imaging System global mosaic between ±65° of latitude, returning a true positive detection rate of 91% and a diameter estimation error (~15%) consistent with typical manual count variation. Importantly, although a number of automated crater counting algorithms have been published, for the first time we demonstrate that automatic counting can be routinely used to derive robust surface ages. Plain Language Summary: Crater counting is the traditional method of determining the surface ages of planets throughout the solar system. This method, up to now, has used data that have been painstakingly counted by hand. The current published database for Mars contains hundreds of thousands of craters for diameters larger than 1 km. If we can count craters smaller than this, we will be able to target specific areas of interest to date. But the rate of impacts on planetary surfaces follows a power law such that the number of small (less than 1 km) craters is exponentially higher than the number of large craters. To count these requires an automated tool. Here we show that we have developed such a tool. We have validated the results against current manual databases. Importantly, and for the first time, we demonstrate that an automated crater counting tool can deliver geologically meaningful ages. Key Points: We built a library of 7,048 craters to train a Crater Detection Algorithm (CDA) that we developed based on a neural network architectureWe applied our algorithm to the Mars global THEMIS mosaic, generating results comparable to manual countingWe applied the CDA to higher‐resolution images generating model ages indistinguishable (within error) from literature ages [ABSTRACT FROM AUTHOR]

Meteoritic matrices are commonly classified by their modal mineralogy, alteration, and shock levels. Other "textural" characteristics are not generally considered in classification schemes, yet could carry important information about their genesis and evolution. Terrestrial rocks are routinely described by grain morphology, which has led to morphology‐driven classifications, and identification of controlling processes. This paper investigates three CV chondrites—Allende (CV3.2oxA), Kaba (CV3.0oxB), and Vigarano (CV3.3red)—to determine the morphologic signature of olivine matrix grains. 2D grain size and shape, and crystallographic preferred orientations (CPOs) are quantified via electron backscatter diffraction mapping. Allende contains the largest and most elongate olivine grains, while Vigarano contains the least elongate, and Kaba contains the smallest grains. Weak but notable CPOs exist in some regions proximal to chondrules and one region distal to chondrules, and CPO geometries reveal a weak flattening of the matrix grains against the edge of chondrules within Allende. Kaba contains the least plastically deformed grains, and Allende contains the most plastically deformed grains. We tentatively infer that morphology is controlled by the characteristics of the available population of accreting grains, and aqueous and thermal alteration of the parent body. The extent of overall finite deformation is likely dictated by the location of the sample with respect to compression, the localized environment of the matrix with respect to surrounding material, and the post deformation temperature to induce grain annealing. Our systematic, quantitative process for characterizing meteorite matrices has the potential to provide a framework for comparison within and across meteorite classes, to help resolve how parent body processing differed across and between chondritic asteroids. [ABSTRACT FROM AUTHOR]

Abstract: We describe the fall of the Dingle Dell (L/LL 5) meteorite near Morawa in Western Australia on October 31, 2016. The fireball was observed by six observatories of the Desert Fireball Network (DFN), a continental‐scale facility optimized to recover meteorites and calculate their pre‐entry orbits. The 30 cm meteoroid entered at 15.44 km s−1, followed a moderately steep trajectory of 51° to the horizon from 81 km down to 19 km altitude, where the luminous flight ended at a speed of 3.2 km s−1. Deceleration data indicated one large fragment had made it to the ground. The four person search team recovered a 1.15 kg meteorite within 130 m of the predicted fall line, after 8 h of searching, 6 days after the fall. Dingle Dell is the fourth meteorite recovered by the DFN in Australia, but the first before any rain had contaminated the sample. By numerical integration over 1 Ma, we show that Dingle Dell was most likely ejected from the Main Belt by the 3:1 mean motion resonance with Jupiter, with only a marginal chance that it came from the ν6 resonance. This makes the connection of Dingle Dell to the Flora family (currently thought to be the origin of LL chondrites) unlikely. [ABSTRACT FROM AUTHOR]

Mason Gully, the second meteorite recovered using the Desert Fireball Network ( DFN), is characterized using petrography, mineralogy, oxygen isotopes, bulk chemistry, and physical properties. Geochemical data are consistent with its classification as an H5 ordinary chondrite. Several properties distinguish it from most other H chondrites. Its 10.7% porosity is predominantly macroscopic, present as intergranular void spaces rather than microscopic cracks. Modal mineralogy (determined via PS- XRD, element mapping via energy dispersive spectroscopy [ EDS], and X-ray tomography [for sulfide, metal, and porosity volume fractions]) consistently gives an unusually low olivine/orthopyroxene ratio (0.67−0.76 for Mason Gully versus ~1.3 for typical H5 ordinary chondrites). Widespread 'silicate darkening' is observed. In addition, it contains a bright green crystalline object at the surface of the recovered stone (diameter ≈ 1.5 mm), which has a tridymite core with minor α-quartz and a rim of both low- and high-Ca pyroxene. The mineralogy allows the calculation of the temperatures and ƒ(O2) characterizing thermal metamorphism on the parent body using both the two-pyroxene and the olivine-chromite geo-oxybarometers. These indicate that MG experienced a peak metamorphic temperature of ~900 °C and had a similar ƒ(O2) to Kernouvé (H6) that was buffered by the reaction between olivine, metal, and pyroxene. There is no evidence for shock, consistent with the observed porosity structure. Thus, while Mason Gully has some unique properties, its geochemistry indicates a similar thermal evolution to other H chondrites. The presence of tridymite, while rare, is seen in other OCs and likely exogenous; however, the green object itself may result from metamorphism. [ABSTRACT FROM AUTHOR]

Bunburra Rockhole is a unique basaltic achondrite that has many mineralogical and petrographic characteristics in common with the noncumulate eucrites, but differs in its oxygen isotope composition. Here, we report a study of the mineralogy, petrology, geochemistry, and chronology of Bunburra Rockhole to better understand the petrogenesis of this meteorite and compare it to the eucrites. The geochemistry of bulk samples and of pyroxene, plagioclase, and Ca-phosphate in Bunburra Rockhole is similar to that of typical noncumulate eucrites. Chronological data for Bunburra Rockhole indicate early formation, followed by slow cooling and perhaps multiple subsequent heating events, which is also similar to some noncumulate eucrites. The 26Al-26Mg extinct radionuclide chronometer was reset in Bunburra Rockhole after the complete decay of 26Al, but a slight excess in the radiogenic 26Mg in a bulk sample allows the determination of a model 26Al-26Mg age that suggests formation of the parent melt for this meteorite from its source magma within the first ~3 Ma of the beginning of the solar system. The 207Pb-206Pb absolute chronometer is also disturbed in Bunburra Rockhole minerals, but a whole-rock isochron provides a re-equilibration age of ~4.1 Ga, most likely caused by impact heating. The mineralogy, geochemistry, and chronology of Bunburra Rockhole demonstrate the similarities of this achondrite to the eucrites, and suggest that it formed from a parent melt with a composition similar to that for noncumulate eucrites and subsequently experienced a thermal history and evolution comparable to that of eucritic basalts. This implies the formation of multiple differentiated parent bodies in the early solar system that had nearly identical bulk elemental compositions and petrogenetic histories, but different oxygen isotope compositions inherited from the solar nebula. [ABSTRACT FROM AUTHOR]

Introduction: The study of martian meteorites has provided a deeper understanding of volcanism on Mars. The small number of samples analyzed have begun to answer large-scale questions pertaining to the geological history of the martian surface. Here, we investigate a basaltic shergottite meteorite from the early Amazonian [1] - one of only two currently known martian meteorites that crystallized at this time [1,2]. Shergottites sample a suite of different lithologies, formation ages, ejection ages and volcanic settings [3], therefore careful consideration of each sub-type is critical to building a wider understanding of martian volcanism as a function of both formation age and location. North-West Africa (NWA) 8159 is the only shergottite classified as an augite basalt [1, 4]. It likely crystallized from an evolved melt at 2.37 ± 0.25 Ga based on Sm-Nd analyses [1], which is much older than the majority of the shergottite group (typically <600 Ma in formation age) [1]. We investigate the crystallization conditions of this early Amazonian rock, and what implications that has for the environment in which it formed. The aim of this initial crystallographic examination is to qualify and quantify any crystallographic textures. These may be used as an indicator for emplacement of the rock, for example in a fast-moving flow or in a cumulate setting. We will also investigate any shock-induced micro- and nano-structures within apatites as an indicator of conditions during impact, and comparisons between apatite grains proximal and distal to the melt vein will also be conducted. Methods & Materials: A 1-inch round epoxy thick section of NWA 8159 (supplied by UNM) was polished for 4 hours using a Vibromet polisher with colloidal silica solution to obtain a reflective surface, and subsequently coated with a ~5 nm carbon coat. Backscatter electron (BSE) and energy dispersive spectrometry (EDS) images were collected at 20 KeV accelerating voltage on the TESCAN TIMA scanning electron microscope (SEM) at the John de Laeter centre (JDLC) at Curtin University. All crystallographic information was then collected using the electron backscatter diffraction (EBSD) on the TESCAN MIRA3 SEM using Oxford Instruments' Symmetry CMOS detector. Large area maps were created based on crystallographic information obtained at a step size of 1 micrometre. Data were processed using AZtecCrystal software, and noise reduction was performed as per common protocol [e.g. 5, 6]. Grains were identified based on a 10° misorientation threshold. Phase, crystallographic orientation and crystal-plastic deformation maps were collected or deduced based on Kikuchi bands recorded by the detector. Results: Preliminary results from earlier large-area mapping demonstrates that much of the sample is crystalline with very little amorphous material present as discovered in prior studies [e.g. 8]. Mineralogy of the large area map is broken down as follows; clinopyroxene 48%; plagioclase feldspar 36%; magnetite 8%; olivine 3%; ~5% attributed to the Ca-rich veins, and other minor phases such as apatite [9]. Crystallographic analysis of this data showed a weak alignment of the <010> axis across the plagioclase grains, whereby the orientation of this axis formed a weak cluster. This axis is typically the shortest crystallographic axis in plagioclase. There is no alignment of the other two axis. Apatites are present across the surface of the exposed sample, and will be further investigated prior to the meeting. Discussion: The presence of an alignment in the <010> axis indicates that a consistent force was applied during the final phase of crystallization of this rock. The lack of alignment in the other two axes suggest this texture was not formed by flow (as in [7]), but rather by a compressive force, such as gravity or impact, whereby the shortest axis of the grains will stack parallel to the direction of the force being applied (e.g. [5]). The limited amount of maskelynite within this sample would indicate this was aligned during crystallization and is therefore interpreted as a gravitational settling texture. This is in agreement with earlier studies, where the groundmass was used to infer a surface lava flow, or shallow sill origin as we find here. Conclusions and further work: The crystallographic alignment of the plagioclase grains examined thus far indicate a settling texture is present. We aim to examine crystallographic properties not only of the plagioclase laths, but also the fine-grained groundmass ahead of the meeting. We will also investigate the apatites across the sample using EBSD and atom probe techniques to compliment the EBSD analyses already performed. [ABSTRACT FROM AUTHOR]

Introduction: Iron meteorites originated on some of the earliest-formed bodies in our Solar System and represent the cores of differentiated planetesimals [1, 2]. They have survived the processes that shaped Solar System architecture, including giant planet migrations and gas disk dissipation [e.g., 3]. Metallographic cooling rates imply rapid cooling of many planetesimal cores, including the IIAB, IIIAB and IVA parent bodies [4]. This was attributed to the impact removal of their mantles. Dating core crystallisation can therefore elucidate the timing of impacts. The 107Pd-107Ag decay system (t1/2 ~6.5 Myr) provides a tool for this. However, early studies of iron meteorites did not fully account for galactic cosmic ray (GCR) exposure, which causes disturbances via secondary neutron capture reactions [5]. Here, we present GCR-corrected parent body initial 107Pd/108Pd ratios for the IAB, IIAB and IIIAB asteroids to date core cooling of planetesimals and constrain dynamic processes occurring in the early Solar System. Results and Discussion: We determined Pd-Ag and Pt isotope compositions for IIAB and IIIAB irons and Pt isotope data for IAB samples where Pd-Ag data were available [1, 6]. Corrections for GCR were applied following [5] and parent-body isochrons were calculated. Corrected data define one IAB isochron with an initial 107Pd/108Pd ratio of ~1.51 x10-5. The IIABs and IIIABs yield isochrons with initial 107Pd/108Pd ratios of ~1.70 x10-5 and ~2.21 x10-5, respectively. The initials of these 3 asteroids are within uncertainty of each other, and the IVAs yield a similar value [7]. This indicates the Pd-Ag system closed in a similar time-frame on these bodies and suggests an energetic inner Solar System at this time. The Pd-Ag cooling ages depend on the Solar System initial (SSI) 107Pd/108Pd. Two SSIs were determined based on the IVA iron Muonionalusta (~3.5 x10-5 [7]) and carbonaceous chondrites (CC) (~5.9 x10-5 [8]). Together, these cover the range of all determined SSI values and we calculated Pd-Ag ages relative to both. Cooling ages for the IIAB, IIIAB and IVA bodies calculated using the IVA iron SSI suggest a highly energetic environment between ~2.9-6.8 Myr after CAI. This corresponds with the suggested outward migration of Jupiter in the Grand Tack model [e.g., 9]. However, this SSI cannot be reconciled with thermal events on the IAB parent body [1]. Closure times relative to CC equate to later cooling between ~7.8-11.7 Myr. This may date the dissipation the gas disk, after which the damping effect of gas drag ceases and energetic collisions are predicted [10]. A giant planet instability ('Nice' model) could also perturb the inner Solar System. Although the precise timing of the instability is difficult to determine, models that predict the size of Mars advocate an instability ~5-14 Myr after CAI [e.g., 11]. Impacts on the iron parent bodies between ~7.8-11.7 Myr agree well with this. Gas dissipation may trigger an early giant planet instability [12] and hence these two mechanisms likely acted together to create an energetic, collisionrich Solar System between ~7.8-11.7 Myr after CAI. [ABSTRACT FROM AUTHOR]

Introduction: The Moon's cratered surface and lack of significant geological activity makes it suitable record for the solar systems chaotic past. The craters scattered across the lunar surface can be mapped and measured giving a relative chronology [1]. Furthermore, the spatial densities of those craters, when linked with radiometric measurements from collected samples, provide absolute model ages [1]. The various sample sites from the Apollo and Luna missions have greatly increased our understanding of the Moon's and Earth's geological evolution [2]. Looking onward to the most recent sample return mission, Chang'e 5 (2022) which brought back 1,731g of material from northeastern Oceanus Procellarum, the in-situ lunar samples host a range of radiometric ages [3,4]. This momentous mission was the first sample return in 44 years, which returned samples from the youngest Mare region on the Moon dated to 1963±57 Ma [3]. Many of the Lunar samples, including those from CE-5, contain clasts that suggest that they have been transported by impacts [4]. This raises questions about where the lunar material originates from, and what can we determine about those areas from the collected sample material. During an impact, a significant amount of material is ejected, and without of atmosphere or strong gravity, this material can travel great distances [5]. This material falls back down to the surface forming a network of secondary craters and debris. Looking at secondary crater clusters around the sample sites, which are typically small (<1km) and number in the several millions [5,6], researchers can determine potential trajectory and distance lunar material has traveled. Specifically for the CE-5 material, probable source locations have been identified through crater mapping and numerical modeling [4]. To aid the time-consuming process of mapping secondary craters we propose using a machine learning algorithm to automatically detect small lunar craters across high-resolution image datasets [7,8,9]. Identifying secondary craters at ultimate resolutions can provide the source of the exogenic material contained in CE-5 samples, and more generally for other lunar samples. Image Datasets: Our team have utilized two high-resolution lunar image datasets for this project. The first was the Lunar Reconnaissance orbiter - Narrow Angle Camera (LRO-NAC), offering a resolution of 0.5-2 m/px [10]; and the second was the Kaguya Terrain Camera (TC), offering a resolution of ~10m/px [11]. This allows us to compile automatic crater detections over across multiple geographical scales. Crater Counting Algorithm: The Crater Detection Algorithm (CDA) is a machine learning image-based Convolutional Neural Network (CNN) that has been specialized to detect craters over high-resolution satellite imagery [7,8,9]. Our CNN uses 'You Only Look Once version 5' (YOLOv5) as the network's architecture. We have two crater detection models, each focusing on a different image dataset (NAC and Kaguya). The NAC model has been trained and validated across 247 square image tiles (416 pixels in length/width) with a detection accuracy of ~92% [9]. The Kaguya model was trained and validated on ~420 tiles and has a detection accuracy of ~94%. All the training image tiles have afternoon/morning lighting conditions, to facilitate impact crater recognition. Before running the detection model across the dataset, they are processed and converted into GeoTiffs through USGS ISIS3 and GDAL, respectively. The CDA is then run across the image datasets, detecting millions of craters at the 10m to 100m scale, magnitudes faster than manual methods. Chang'e 5 Secondary Clusters: The preliminary results over the Chang'e 5 landing site and surrounding areas show multiple secondary clusters (>10) cross cutting the region. At the Kaguya-scale (10m/px), we analyzed a ~800km by ~800km region and found considerable secondary clusters that crosscut the landing region from Aristarchus crater. At the NAC-scale (2m/px), we analyzed a ~450km by ~275km area and located a significant secondary cluster less that 10km from the landing site, originating from Rümke E crater. We also mapped a series of north-west and eastwest trending clusters. Acknowledgments: This work is supported by the resources provided by the Pawsey Supercomputing Centre with funding from the Australian Government, Curtin University, and the Government of Western Australia. [ABSTRACT FROM AUTHOR]

Introduction: The geological record of the formation and differentiation of our planet has been destroyed by its subsequent evolution, but extremely rare clues may be obtained from other terrestrial planets. Mars provides a unique and accessible example of an early evolutionary path corresponding to that, inaccessible, of our own world. We can investigate it with spacecraft, and samples are available for in-depth analysis on Earth in the form of martian meteorites. So far, the only available martian samples that appear to have recorded the early conditions and the evolution of the planet until the present time are Northwest Africa (NWA) 7034 and its paired stones, nicknamed "Black Beauty". This regolith breccia has been ejected a few million years ago by the formation of a large impact crater, and contains the oldest martian igneous material ever dated: ~4.5 Ga old [1-4]. However, its source and geological context have so far remained unknown. and with it, a region where the earliest geological records of the planet [1-4] are exposed on the surface. Knowing this source region would provide insights into early Mars geological history and crustal extraction [1-4]. This source region may therefore become a high-priority target for detailed orbital analyses and in-situ exploration [5]. Constraints on the meteorite launch site: Following a hypervelocity impact, ejecta materials moving faster than the escape velocity (5 km/s) may get through the martian atmosphere and continue their course into interplanetary space to become martian meteorites [6]. Slower debris fall back on the surface in a radial pattern or ray around the primary crater, forming secondary craters. The presence of 100 meter-size secondaries attests to the freshness of their associated primary craters [7]. Using the size and spatial distribution of more than 90 million impact craters >50 m (both primaries and secondaries) detected using a Crater Detection Algorithm (CDA) [7-8] on the whole surface of Mars from the global Context Camera (CTX) mosaic [9], a previous work [7] identified ray systems of secondary craters <150 m associated with 19 large primary craters, potential source of the ejection of martian meteorites. Here we compare the abundance of K and Th [10-11] as well as the magnetic field intensity and the magnetization of the surface of Mars derived from orbital measurements [12] at the immediate vicinity of each crater candidate with those of the breccia. We also compare the geological context of each of the crater candidates with the chronology and the lithology of the meteorite [e.g. 1-3, 13-14]. The ejection site for Black Beauty: Among the 19 crater candidates investigated, we found that only one match with the characteristics of the meteorite: a 10 km crater located in the north-east of the Terra Cimeria - Sirenum (TCTS) region, between Hesperia Planum and the Tharsis bulge. Our work suggests that clasts contained in the regolith breccia are representative of the TCTS province, making this region a relic of the early crustal processes on Mars [e.g. 15], and thus, a region of high interest for future missions. Details on the identification of the crater source of this unique meteorite, as well a its geological context and broader implications for early crustal processes on Mars will be presented at the conference. [ABSTRACT FROM AUTHOR]

Background. Evidence-based data on optimal approach for prophylaxis of deep venous thrombosis (VTE) and pulmonary embolism (PE) in bariatric operations is discussed. Using antithrombotic prophylaxis weight adjusted the risk of VTE and its complications have to be balanced with the increased bleeding risk. Methods. Since 2005 the current situation for bariatric surgery has been examined by quality assurance study in Germany. As a prospective multicenter observational study, data on the type, regimen, and time course of VTE prophylaxis were documented. The incidences of clinically diagnosed VTE or PE were derived during the in-hospital course and follow up. Results. Overall, 11,835 bariatric procedures were performed between January 2005 and December 2010. Most performed procedures were 2730 gastric banding (GB); 4901 Roux-en-Y-gastric bypass (RYGBP) procedures, and 3026 sleeve gastrectomies (SG). Study collective includes 72.5% (mean BMI 48.1 kg/m2) female and 27.5% (mean BMI 50.5 kg/m2) male patients. Incidence of VTE was 0.06% and of PE 0.08%. Conclusion. VTE prophylaxis regimen depends on BMI and the type of procedure. Despite the low incidence of VTE and PE there is a lack of evidence. Therefore, prospective randomized studies are necessary to determine the optimal VTE prophylaxis for bariatric surgical patients. [ABSTRACT FROM AUTHOR]

In eukaryotes, protein transport into the endoplasmic reticulum (ER) is facilitated by a protein-conducting channel, the Sec61 complex. The presence of large, water-filled pores with uncontrolled ion permeability, as formed by Sec61 complexes in the ER membrane, would seriously interfere with the regulated release of calcium from the ER lumen into the cytosol, an essential mechanism for intracellular signalling. We identified a calmodulin (CaM)-binding motif in the cytosolic N-terminus of mammalian Sec61α that bound CaM but not Ca2+-free apocalmodulin with nanomolar affinity and sequence specificity. In single-channel measurements, CaM potently mediated Sec61-channel closure in Ca2+-dependent manner. At the cellular level, two different CaM antagonists stimulated calcium release from the ER through Sec61 channels. However, protein transport into microsomes was not modulated by Ca2+-CaM. Molecular modelling of the ribosome/Sec61/CaM complexes supports the view that simultaneous ribosome and CaM binding to the Sec61 complex may be possible. Overall, CaM is involved in limiting Ca2+ leakage from the ER. [ABSTRACT FROM AUTHOR]

- In this edition of The Meteoritical Bulletin, a total of 506 newly approved meteorite names with their relevant data are reported. These include 354 from northwest Africa, 31 from the Americas, 15 from Antarctica (Koreamet), 85 from Asia, 20 from Australia, and 1 from Europe. Among these meteorites are 2 falls, Grimsby (Canada) and Santa Lucia (2008) (Argentina). Also described are a CM with low degree of alteration, new ungrouped chondrites and achondrites, and 4 Martian meteorites. [ABSTRACT FROM AUTHOR]