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A multi-instrument study of the regolith of Jezero crater floor units by the Perseverance rover has identified three types of regolith: fine-grained, coarse-grained, and mixed-type. Mastcam-Z, Wide Angle Topographic Sensor for Operations and eNgineering, and SuperCam Remote Micro Imager were used to characterize the regolith texture, particle size, and roundedness where possible. Mastcam-Z multispectral and SuperCam laser-induced breakdown spectroscopy data were used to constrain the composition of the regolith types. Fine-grained regolith is found surrounding bedrock and boulders, comprising bedforms, and accumulating on top of rocks in erosional depressions. Spectral and chemical data show it is compositionally consistent with pyroxene and a ferric-oxide phase. Coarse-grained regolith consists of 1-2 mm well-sorted gray grains that are found concentrated around the base of boulders and bedrock, and armoring bedforms. Its chemistry and spectra indicate it is olivine-bearing, and its spatial distribution and roundedness indicate it has been transported, likely by saltation-induced creep. Coarse grains share similarities with the olivine grains observed in the S & eacute;& iacute;tah formation bedrock, making that unit a possible source for these grains. Mixed-type regolith contains fine-and coarse-grained regolith components and larger rock fragments. The rock fragments are texturally and spectrally similar to bedrock within the M & aacute;az and S & eacute;& iacute;tah formations, indicating origins by erosion from those units, although they could also be a lag deposit from erosion of an overlying unit. The fine and coarse-grained types are compared to their counterparts at other landing sites to inform global, regional, and local inputs to regolith formation within Jezero crater. The regolith characterization presented here informs the regolith sampling efforts underway by Perseverance.Plain Language Summary We used multiple instruments on the Perseverance rover to describe three populations of loose sediments found on the floor of Jezero crater by their grain sizes and chemical compositions. The smallest population has grains that are small sand-sized (80-530 mu m) and a mixture of minerals commonly found on Mars, including pyroxene that is present in local rocks and airborne dust found globally. These grains are the easiest to move by wind, so could have distal regional sources as well. Larger gray grains that are 1-2 mm in size and rounded contain olivine. These grains move along the surface, pushed by the impacts of smaller grains that are lifted by the wind. Their size and composition are very similar to olivine grains found in nearby in-place rocks, indicating that they may have a more local source. Finally, there are larger pieces of rocks that have broken down from the erosion of local in-place rocks over time and mix with the other types of grains. Loose sediments within the Jezero crater described here can be compared to loose sediments studied at other landing sites on Mars to help understand how Jezero sediments are formed and transported.

d-Serine is a coagonist of the

The inferred subsurface oceans of the icy moons of Jupiter and Saturn, in particular Europa and Enceladus, may contain conditions suitable for life. Plumes of material have been detected from Enceladus and may also be present on Europa. These plumes could contain molecular signs of habitability that could be detected by mass spectrometers on orbiting spacecrafts, such as the upcoming Europa Clipper mission. However, these molecular markers may have degraded between their production and detection, for example by possible hydrothermalism in the subsurface ocean or by UV irradiation once carried into space by the plume. It is important to look at how the biosignatures degrade under different conditions as degradation processes need to be taken into account when analysing the data from life detection missions. We investigate how these two processes affect the mass spectral signals of terrestrial bacteria. Two cyanobacteria samples, Spirulina and Chlorella, were subjected to hydrothermal processing and UV irradiation. Hydrous pyrolysis was used to simulate hydrothermal degradation. Experiments were carried out for 24 or 72 hours at temperatures between 200 and 300 °C. The pyrolyzed contents were subsequently extracted and analysed with gas chromatography-mass spectrometry (GC-MS). UV irradiation was carried out in a vacuum chamber (10-2 mbar), using a 300 W short arc xenon lamp at UV to near infrared wavelengths (~250 – 800 nm). After UV irradiation, samples were analysed using pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). Our results show that hydrothermal processing of cyanobacteria affects the compound classes in different ways. Carbohydrate and protein components from the cyanobacteria were significantly affected, with phenol and indole derivatives detected. However, some of the biological fingerprint, such as straight-chain even numbered saturated fatty acids from lipid fragments, remain even at the harshest experimental conditions used in our study. This provides confidence that these diagnostic molecules could be used as fingerprints of biological materials on icy moons.

It has been 4 years since the introduction of the inflammatory bowel disease (IBD) Service Standards ( IBD Standards Group, 2009 ). Promoted widely and supported by quality improvement initiatives, the IBD Standards have contributed to a marked improvement in the delivery of IBD services and care, as measured by the IBD audit. However, there remain many challenges. The 2013 updated IBD Standards aim to provide a comprehensive and up-to-date framework that will enable IBD services across the UK to address challenges and deliver a consistent and high-quality service to IBD patients. This article will outline the need for change and current trends in the NHS, the differences between the original and revised IBD Standards, the role of the new IBD Standards in improving care across the country, the role of the IBD specialist nurse in relation to the IBD Standards and what IBD patients can expect in the future.

Oral mesalazine represents a crucial front-line agent for the treatment of active ulcerative colitis (UC) and the maintenance of remission. Clinical aspects of mesalazine therapy are guided by robust evidence-based guidelines, although there is a relative paucity of guidance examining the specific administrative and professional issues faced by inflammatory bowel disease (IBD) nurses. As IBD nurses frequently influence treatment decisions in UC, this article was written to provide a practical review of the key evidence and issues affecting mesalazine treatment. Therefore, it may act as an additional resource for IBD nurses, to enhance prescribing decisions. Using the UK's Quality, Innovation, Productivity and Prevention (QIPP) agenda as a framework, it considers clinical and health service priorities affecting treatment decisions. The quality of care perspective naturally focuses on efficacy; recent interest in specific aspects of efficacy, such as the speed of symptom resolution allows targeting of mesalazine treatment to individual needs. Furthermore, innovative adherence programmes build on the latest evidence to develop robust, integrated patient support approaches. In terms of productivity, nurse-led activities and more sophisticated management strategies may offer the best routes towards reducing the costs of care. Key opportunities for preventing ill health include improving adherence to maintenance therapy and achieving mucosal healing. The principles and approaches highlighted by the QIPP agenda emphasise that prescribing decisions for mesalazine in UC must take account of the full spectrum of clinical and health service needs, and cannot focus on any one element in isolation.

More needs to be done to address the professional issues that arise from inflammatory bowel disease (IBD) specialist nurse practice. The lack of regulation of advanced nurse practitioner (ANP) roles in the UK raises questions in relation to inconsistencies of benchmark standards, scope of practice and qualification processes. A review of the literature supports the view that a competency framework for ANP roles would demonstrate knowledge and skills in the absence of UK regulation. The benefits of such a framework have already been recognised in different areas of gastroenterology and other specialties. A specific competency framework is required for IBD specialist nurses to provide transparency and governance in this area of practice.

Ulcerative colitis is a relapsing chronic disease that has an unpredictable course. A relapse in the condition requires timely intervention and expert monitoring. A severe flare-up will often necessitate admission to hospital. This article provides an overview of the medical management of severe ulcerative colitis and the nursing interventions required.

Background and aims The emphasis for healthcare clinicians to provide adequate disease-related education is increasing. Yet little is known about the effect of providing disease-related education within inflammatory bowel disease (IBD). Previous studies have demonstrated increased levels of knowledge and satisfaction, but failed to capture any positive effects on the psychosocial elements of living with IBD. The aim of this qualitative study was to evaluate the impact of providing a group patient education programme on the psychosocial elements of living with IBD. Methods The data were obtained through eight semistructured qualitative interviews. Participants were recruited at the education programme using purposive sampling. All the interviews were digital recorded and transcribed. Thematic analysis was used by two independent researchers to analyse the transcripts and agreed emerging themes. Results A global theme of ‘mastery’ was evident within the transcripts. This was underpinned with two core themes of enablement and cooperative learning. The education programme ‘enabled’ the participants in a variety of ways: increased confidence, control, courage and power over their disease. An unexpected core theme of cooperative learning was also identified, with participants describing the overwhelming benefit of interaction with other people who also had IBD. Conclusions This is the first qualitative study to report on the effects of providing a group patient education within IBD. The results identify new and interesting psychosocial elements that existing quantitative studies have failed to identify.