Fine-regolith production on asteroids controlled by rock porosity.

Spacecraft missions have observed regolith blankets of unconsolidated subcentimetre particles on stony asteroids1-3. Telescopic data have suggested the presence of regolith blankets also on carbonaceous asteroids, including (101955) Bennu4 and (162173) Ryugu5. However, despite observations of processes that are capable of comminuting boulders into unconsolidated materials, such as meteoroid bombardment6,7 and thermal cracking8, Bennu and Ryugu lack extensive areas covered in subcentimetre particles7,9. Here we report an inverse correlation between the local abundance of subcentimetre particles and the porosity of rocks on Bennu. We interpret this finding to mean that accumulation of unconsolidated subcentimetre particles is frustrated where the rocks are highly porous, which appears to be most of the surface10. The highly porous rocks are compressed rather than fragmented by meteoroid impacts, consistent with laboratory experiments11,12, and thermal cracking proceeds more slowly than in denser rocks. We infer that regolith blankets are uncommon on carbonaceous asteroids, which are the most numerous type of asteroid13. By contrast, these terrains should be common on stony asteroids, which have less porous rocks and are the second-most populous group by composition13. The higher porosity of carbonaceous asteroid materials may have aided in their compaction and cementation to form breccias, which dominate the carbonaceous chondrite meteorites14.

The unexpected surface of asteroid (101955) Bennu.

NASA'S Origins, Spectral Interpretation, Resource Identification and Security-Regolith Explorer (OSIRIS-REx) spacecraft recently arrived at the near-Earth asteroid (101955) Bennu, a primitive body that represents the objects that may have brought prebiotic molecules and volatiles such as water to Earth1. Bennu is a low-albedo B-type asteroid2 that has been linked to organic-rich hydrated carbonaceous chondrites3. Such meteorites are altered by ejection from their parent body and contaminated by atmospheric entry and terrestrial microbes. Therefore, the primary mission objective is to return a sample of Bennu to Earth that is pristine-that is, not affected by these processes4. The OSIRIS-REx spacecraft carries a sophisticated suite of instruments to characterize Bennu's global properties, support the selection of a sampling site and document that site at a sub-centimetre scale5-11. Here we consider early OSIRIS-REx observations of Bennu to understand how the asteroid's properties compare to pre-encounter expectations and to assess the prospects for sample return. The bulk composition of Bennu appears to be hydrated and volatile-rich, as expected. However, in contrast to pre-encounter modelling of Bennu's thermal inertia12 and radar polarization ratios13-which indicated a generally smooth surface covered by centimetre-scale particles-resolved imaging reveals an unexpected surficial diversity. The albedo, texture, particle size and roughness are beyond the spacecraft design specifications. On the basis of our pre-encounter knowledge, we developed a sampling strategy to target 50-metre-diameter patches of loose regolith with grain sizes smaller than two centimetres4. We observe only a small number of apparently hazard-free regions, of the order of 5 to 20 metres in extent, the sampling of which poses a substantial challenge to mission success.

Primary care usage at the end of life: a retrospective cohort study of cancer patients using linked primary and hospital care data.

PURPOSE: Health service use is most intensive in the final year of a person's life, with 80% of this expenditure occurring in hospital. Close involvement of primary care services has been promoted to enhance quality end-of-life care that is appropriate to the needs of patients. However, the relationship between primary care involvement and patients' use of hospital care is not well described. This study aims to examine primary care use in the last year of life for cancer patients and its relationship to hospital usage. METHODS: Retrospective cohort study in Victoria, Australia, using linked routine care data from primary care, hospital and death certificates. Patients were included who died related to cancer between 2008 and 2017. RESULTS: A total of 758 patients were included, of whom 88% (n = 667) visited primary care during the last 6 months (median 9.1 consultations). In the last month of life, 45% of patients were prescribed opioids, and 3% had imaging requested. Patients who received home visits (13%) or anticipatory medications (15%) had less than half the median bed days in the last 3 months (4 vs 9 days, p < 0.001, 5 vs 10 days, p = 0.001) and 1 month of life (0 vs 2 days, p = 0.002, 0 vs 3 days, p < 0.001), and reduced emergency department presentations (32% vs 46%, p = 0.006, 31% vs 47% p < 0.001) in the final month. CONCLUSION: This study identifies two important primary care processes-home visits and anticipatory medication-associated with reduced hospital usage and intervention at the end of life.

Health-related quality of life in rural cancer survivors compared with their urban counterparts: a systematic review.

PURPOSE: We conducted a systematic review to describe health-related quality of life (HRQOL) in rural cancer survivors (RCS), and compare HRQOL between RCS and urban cancer survivors (UCS). METHOD: We searched Medline, Embase, CINAHL Plus, and PsycINFO for studies with HRQOL in adult cancer survivors living in rural, regional, remote, and urban areas, who had completed definitive primary cancer treatment, without evidence of residual disease. Where available, we used normative and clinically important values to ascribe meaning to HRQOL data. FINDINGS: Fifteen studies (16 papers) were included. Most were from the US (n = 8) and reported on breast cancer survivors (n = 9). Six HRQOL instruments, collecting data across 16 domains, were used. Three instruments were specific to the survivorship phase. Normative and clinical data were available for 12 studies. Compared with normative populations, RCS had clinically worse physical HRQOL (6/12 studies), better social/family (5/7), and functional (3/6) HRQOL, and there were no differences in emotional or/mental HRQOL (9/12). In six studies with rural-urban comparator groups and normative and clinically important data, RCS and UCS had clinically worse physical (3/6 and 2/6, respectively) and better social/family (3/4 and 2/4 studies, respectively) HRQOL than normative populations. Functional HRQOL was better in RCS (2/4 studies) than UCS and normative populations. In 3/6 studies, there were no clinical differences in emotional or/mental HRQOL between RCS, UCS, and normative populations. CONCLUSION: Overall, HRQOL is not clearly better or worse in RCS than UCS. Future research should include different tumor types, rural residents, and survivorship-specific HRQOL instruments.

Implementation of cancer prevention practices in primary care: results of a cohort study in Chile 2018-2022.

OBJECTIVES: The burden of cancer is increasing rapidly in Latin America. Primary care has an essential role in cancer prevention, but implementation levels of prevention practices are not well known. This study evaluated implementation levels and associated factors of cancer preventive practices in primary care over time. STUDY DESIGN: The study incorporated a retrospective multicentre cohort study. METHODS: A population of 59,949 patients registered at three primary care clinics was followed from January 2018 to December 2022 in Santiago, Chile. We studied human papillomavirus (HPV) and hepatitis B virus (HBV) immunisation, brief counselling for smoking cessation and alcohol consumption, and cervical and breast cancer screening practices. Standardised electronic medical records were utilised as the source of information. Social, clinical, and organisational factors associated with prevention practices were studied. RESULTS: The cohort attrition level was 17.1%. Most of the population was of a low socioeconomic status, and 70% visited a primary health centre yearly. Implementation rates of immunisation practices were 90.84% for HPV and 80.94% for HBV in 2022. In contrast, brief counselling for smoking and alcohol consumption was below 20% during the study period. Cervical cancer screening decreased by 25.58% between 2018 and 2022, whereas breast cancer screening reached only 41.71% of the target population. Opportunistic medical visits were strongly associated with brief counselling and breast cancer screening. CONCLUSION: Implementation practices for cancer prevention in a Chilean primary care cohort are high for immunisation and very low for brief counselling and screening practices. A comprehensive non-medical-based model is needed to improve cancer prevention in primary care.

The Hunter-8 Scale Prehospital Triage Workflow for Identification of Large Vessel Occlusion and Brain Haemorrhage.

OBJECTIVE: The Hunter-8 prehospital stroke scale predicts large vessel occlusion in hyperacute ischemic stroke patients (LVO) at hospital admission. We wished to test its performance in the hands of paramedics as part of a prehospital triage algorithm. We aimed to determine (a) the proportion of patients identified by the Hunter-8 algorithm, receiving reperfusion therapies, (b) whether a call to stroke team improved this, and (c) performance for LVO detection using an expanded LVO definition. METHODS: A prehospital workflow combining pre-morbid functional status, time from symptom onset, and the Hunter-8 scale was implemented from July 2019. A telephone call to the stroke team was prompted for potential treatment candidates. Classic LVO was defined as a proximal middle cerebral artery (MCA-M1), terminal internal carotid artery, or tandem occlusion. Extended LVO added proximal MCA-M2 and basilar occlusions. RESULTS: From July 2019 to April 2021, there were 363 Hunter-8 activations, 320 analyzed: 181 (56.6%) had confirmed ischemic strokes, 13 (4.1%) transient ischemic attack, 91 (28.5%) stroke mimics, and 35 (10.9%) intracranial hemorrhage. Fifty-two patients (16.3%) received reperfusion therapies, 35 with Hunter-8 ≥ 8. The stroke doctor changed the final destination for 76 patients (23.7%), and five received reperfusion therapies. The AUCs for classic and extended LVO were 0.73 (95% CI 0.66-0.79) and 0.72 (95% CI 0.65-0.77), respectively. CONCLUSION: The Hunter-8 workflow resulted in 28.7% of confirmed ischemic stroke patients receiving reperfusion therapies, with no secondary transfers to the comprehensive stroke center. The role of communication with stroke team needs to be further explored.

Characteristics of Posttraumatic Nightmares and Their Relationship to PTSD Severity Among Combat Veterans With PTSD and Hazardous Alcohol Use.

ABSTRACT: Although nightmares are known to predict the clinical course of posttraumatic stress disorder (PTSD), research on the relationship between specific nightmare characteristics and PTSD severity is sparse. This study conducted a secondary analysis to explore how five nightmare characteristics are cross-sectionally related to PTSD severity in 76 combat veterans with PTSD and at-risk alcohol use. Consistent with emotional processing theory, we hypothesized that more replicative, threatening, realistic, and easily recalled nightmares would be associated with more severe PTSD, whereas those with greater symbolism would predict lower PTSD severity. Nightmares narratives were audio-recorded and rated by multiple coders. Multiple analyses of variance explored the relationship between nightmare characteristics and PTSD clinical indicators. Most nightmares were realistic, easily recalled, and involved significant threat. Greater realism and replication were associated with greater PTSD severity. Realistic and replicative nightmares may be markers of more severe PTSD and may indicate that less emotional processing of the trauma has occurred.

Correction: External validation of risk prediction models for incident colorectal cancer using UK Biobank.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Dermoscopy use in UK primary care: a survey of GPs with a special interest in dermatology.

BACKGROUND: Melanoma accounts for 90% of skin cancer mortality and typically presents in primary care, where it can be challenging to distinguish from benign lesions. Dermoscopy is a tool for skin visualization that is routinely used for melanoma diagnosis in secondary care. However, the role of dermoscopy in primary care remains unclear. OBJECTIVES: To determine views on, and use of, dermoscopy by dermatology-interested general practitioners (GPs). METHODS: An online questionnaire was emailed to the UK Primary Care Dermatology Society members in February 2018, and responses collected over the following 4 weeks. RESULTS: A total of 205 responses were analysed. Most respondents were GPs (94%), aged over 50 (53%), had a postgraduate dermatological qualification (67%) and used dermoscopy regularly when reviewing pigmented skin lesions (97%). Dermoscopy use was commoner amongst GPs who had worked longer in primary care and had experience of secondary care dermatology. Most had undertaken training in dermoscopy (91%), although one-fifth (20%) had not updated their training in over 5 years. Most of those who had received only 1 day of face-to-face training reported feeling confident using a dermatoscope. Few respondents (11%) reported access to teledermatology or teledermoscopy for urgent or routine referrals. CONCLUSIONS: UK GPs with a special interest in dermatology are routinely using dermoscopy in the primary care setting. More research is needed to establish optimal approaches to training and updating GP dermoscopy skills. When dermoscopy has been shown to be safe, effective, acceptable and cost-effective in this setting, more GPs may also be able to gain and maintain the skills to implement dermoscopy into routine primary care. Technological advances, including incorporation of artificial intelligence (AI) and algorithms to guide GPs, could also contribute to widening use of dermoscopy among GPs.

External validation of risk prediction models for incident colorectal cancer using UK Biobank.

BACKGROUND: This study aimed to compare and externally validate risk scores developed to predict incident colorectal cancer (CRC) that include variables routinely available or easily obtainable via self-completed questionnaire. METHODS: External validation of fourteen risk models from a previous systematic review in 373 112 men and women within the UK Biobank cohort with 5-year follow-up, no prior history of CRC and data for incidence of CRC through linkage to national cancer registries. RESULTS: There were 1719 (0.46%) cases of incident CRC. The performance of the risk models varied substantially. In men, the QCancer10 model and models by Tao, Driver and Ma all had an area under the receiver operating characteristic curve (AUC) between 0.67 and 0.70. Discrimination was lower in women: the QCancer10, Wells, Tao, Guesmi and Ma models were the best performing with AUCs between 0.63 and 0.66. Assessment of calibration was possible for six models in men and women. All would require country-specific recalibration if estimates of absolute risks were to be given to individuals. CONCLUSIONS: Several risk models based on easily obtainable data have relatively good discrimination in a UK population. Modelling studies are now required to estimate the potential health benefits and cost-effectiveness of implementing stratified risk-based CRC screening.

Identifying people at higher risk of melanoma across the U.K.: a primary-care-based electronic survey.

BACKGROUND: Melanoma incidence is rising rapidly worldwide among white populations. Defining higher-risk populations using risk prediction models may help targeted screening and early detection approaches. OBJECTIVES: To assess the feasibility of identifying people at higher risk of melanoma using the Williams self-assessed clinical risk estimation model in U.K. primary care. METHODS: We recruited participants from the waiting rooms of 22 general practices covering a total population of > 240 000 in three U.K. regions: Eastern England, North East Scotland and North Wales. Participants completed an electronic questionnaire using tablet computers. The main outcome was the mean melanoma risk score using the Williams melanoma risk model. RESULTS: Of 9004 people approached, 7742 (86%) completed the electronic questionnaire. The mean melanoma risk score for the 7566 eligible participants was 17·15 ± 8·51, with small regional differences [lower in England compared with Scotland (P = 0·001) and Wales (P < 0·001), mainly due to greater freckling and childhood sunburn among Scottish and Welsh participants]. After weighting to the age and sex distribution, different potential cut-offs would allow between 4% and 20% of the population to be identified as higher risk, and those groups would contain 30% and 60%, respectively of those likely to develop melanoma. CONCLUSIONS: Collecting data on the melanoma risk profile of the general population in U.K. primary care is both feasible and acceptable for patients in a general practice setting, and provides opportunities for new methods of real-time risk assessment and risk stratified cancer interventions.

How rural and urban patients in Australia with colorectal or breast cancer experience choice of treatment provider: A qualitative study.

Modern healthcare systems promote patient choice of cancer treatment provider, but little is known about how place of residence influences decision-making. This research explored how rural and urban patients with breast or colorectal cancer experience choice of cancer treatment provider in Victoria, Australia. Realist thematic analysis of 43 semi-structured telephone interviews identified little active participation in decision-making regardless of area of residence or cancer diagnosis. Perceptions of choice were impacted by urgency for treatment, insurance status and access to providers, a key issue for rural patients. All patients wanted high quality care, but needed to trust health professional's recommendations. Rural patients experienced more complex decision-making, balancing a range of social factors with perceptions about quality of accessible care. Further research into variation in quality of care and complex cancer pathways for rural and urban cancer patients is warranted to inform choices and enhance patient-centred care.

Cancer beliefs in ethnic minority populations: a review and meta-synthesis of qualitative studies.

People from ethnic minorities often experience poorer cancer outcomes, possibly due to later presentation to healthcare and later diagnosis. We aimed to identify common cancer beliefs in minority populations in developed countries, which can affect symptom appraisal and help seeking for symptomatic cancer. Our systematic review found 15 relevant qualitative studies, located in the United Kingdom (six), United States (five), Australia (two) and Canada (two) of African, African-American, Asian, Arabic, Hispanic and Latino minority groups. We conducted a meta-synthesis that found specific emotional reactions to cancer, knowledge and beliefs and interactions with healthcare services as contributing factors in help seeking for a cancer diagnosis. These findings may be useful to inform the development of interventions to facilitate cancer diagnosis in minority populations.

Further validation and reliability testing of the Rotator Cuff Quality of Life Index (RC-QOL) according to the Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines.

BACKGROUND: The Rotator Cuff Quality of Life Index (RC-QOL) was developed to evaluate quality of life in patients with rotator cuff disorders (RCD). The purpose of this study was to provide additional reliability, validity, and responsiveness testing in accordance with the Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines. METHODS: Preliminary patient interviews included 15 patients. Seventy patients (mean age, 58; standard deviation, 9 years) with RCD were evaluated. Methodology testing included internal consistency, test-retest reliability, measurement error, content validity, and construct validity. Responsiveness, interpretability, and generalizability were also analyzed. RESULTS: The Cronbach α was 0.96 (95% confidence interval, 0.89-0.99; range, 0.72-0.94). The intraclass correlation coefficient for the RC-QOL was 0.87 (95% confidence interval, 0.79-0.85; range, 0.77-0.88). The standard error of measurement was 8 (range, 7-13). The smallest detectable change was 3 (range, 2-4). Content validity was confirmed through standardized patient interviews. All a priori hypotheses were confirmed. No floor or ceiling effects were present. The minimally clinical important difference ranged between 7 and 14 points. The study met the COSMIN criteria for interpretability and generalizability. CONCLUSION: The RC-QOL is a reliable and valid measure of health-related quality of life in patients with chronic RCD. The results of this study added to the methodologic quality assessment of the RC-QOL, completing 7 of 10 COSMIN criteria.

Introductory Dialogue and the Köhler Effect in Software-Generated Workout Partners.

OBJECTIVES: This study explored the Köhler motivation gain effect utilizing adults and software-generated partners (SGPs) during an abdominal exercise regimen and compared the type of participant-SGP introductory dialogue as a moderator. The Köhler effect applies interdependent team dynamics in which group performance is dependent upon the weaker member. The third objective was to examine if this motivation paradigm would result in adverse consequences to secondary variables: exertion, enjoyment, and self-efficacy beliefs. DESIGN: Adults (Mage = 38.8 +/- 7.7) were randomly assigned to 1 of 3 conditions: Interactive Partner SGP (IP), Linear Dialogue Partner SGP (LDP), or individual control (IC), to complete a series of abdominal exercises. The experiment used a 3 (condition) x 2 (gender) ANCOVA design, with a baseline block of exercises as a covariate. METHOD: Participants completed abdominal exercises individually and, after a rest, repeated the same exercises with either an SGP programmed to be moderately stronger or individually (IC). Prior to the second exercise block, IP participants interacted with the SGP using a dialog tree optional-response format. The LDP participant introduction was a linear, scripted exchange of basic information. RESULTS: The LDP and IP conditions persisted significantly longer than IC, generating moderate effect sizes (d = .62; d = .76). The mean difference between partnered conditions was not significant. CONCLUSIONS: The Köhler motivation exercise paradigm resulted in a considerable increase in persistence (Madj = 28.9, SE = 10.6) in the first study to use middle-aged adults with superior SGPs. Differences between introductory dialogue methods were not significant.

Innovation, productivity, and pricing: Capturing value from precision medicine technology in Canada.

For new technology and innovation such as precision medicine to become part of the solution for the fiscal sustainability of Canadian Medicare, decision-makers need to change how services are priced rather than trying to restrain emerging technologies like precision medicine for short-term cost savings. If provincial public payers shift their thinking to be public purchasers, value considerations would direct reform of the reimbursement system to have prices that adjust with technologically driven productivity gains. This strategic shift in thinking is necessary if Canadians are to benefit from the promised benefits of innovations like precision medicine.

Implementing a QCancer risk tool into general practice consultations: an exploratory study using simulated consultations with Australian general practitioners.

BACKGROUND: Reducing diagnostic delays in primary care by improving the assessment of symptoms associated with cancer could have significant impacts on cancer outcomes. Symptom risk assessment tools could improve the diagnostic assessment of patients with symptoms suggestive of cancer in primary care. We aimed to explore the use of a cancer risk tool, which implements the QCancer model, in consultations and its potential impact on clinical decision making. METHODS: We implemented an exploratory 'action design' method with 15 general practitioners (GPs) from Victoria, Australia. General practitioners applied the risk tool in simulated consultations, conducted semi-structured interviews based on the normalisation process theory and explored issues relating to implementation of the tool. RESULTS: The risk tool was perceived as being potentially useful for patients with complex histories. More experienced GPs were distrustful of the risk output, especially when it conflicted with their clinical judgement. Variable interpretation of symptoms meant that there was significant variation in risk assessment. When a risk output was high, GPs were confronted with numerical risk outputs creating challenges in consultation. CONCLUSIONS: Significant barriers to implementing electronic cancer risk assessment tools in consultation could limit their uptake. These relate not only to the design and integration of the tool but also to variation in interpretation of clinical histories, and therefore variable risk outputs and strong beliefs in personal clinical intuition.

Symptoms and other factors associated with time to diagnosis and stage of lung cancer: a prospective cohort study.

BACKGROUND: This prospective cohort study aimed to identify symptom and patient factors that influence time to lung cancer diagnosis and stage at diagnosis. METHODS: Data relating to symptoms were collected from patients upon referral with symptoms suspicious of lung cancer in two English regions; we also examined primary care and hospital records for diagnostic routes and diagnoses. Descriptive and regression analyses were used to investigate associations between symptoms and patient factors with diagnostic intervals and stage. RESULTS: Among 963 participants, 15.9% were diagnosed with primary lung cancer, 5.9% with other thoracic malignancies and 78.2% with non-malignant conditions. Only half the cohort had an isolated first symptom (475, 49.3%); synchronous first symptoms were common. Haemoptysis, reported by 21.6% of cases, was the only initial symptom associated with cancer. Diagnostic intervals were shorter for cancer than non-cancer diagnoses (91 vs 124 days, P=0.037) and for late-stage than early-stage cancer (106 vs 168 days, P=0.02). Chest/shoulder pain was the only first symptom with a shorter diagnostic interval for cancer compared with non-cancer diagnoses (P=0.003). CONCLUSIONS: Haemoptysis is the strongest symptom predictor of lung cancer but occurs in only a fifth of patients. Programmes for expediting earlier diagnosis need to focus on multiple symptoms and their evolution.