University of Northampton

ABSTRACT This study presents a qualitative, case-based risk assessment to evaluate participant safety and regulatory accountability in suborbital spaceflight. Currently, the suborbital flight sector is operating under a regulatory “learning period” moratorium that offers minimal oversight from the Federal Aviation Administration’s Office of Commercial Space Transportation (FAA-AST). A qualitative Bowtie-based case study is presented herein, applying the ICAO risk matrix and the ALARP (As Low As Reasonably Practicable) methodology to a representative loss-of-pressurization scenario in Blue Origin’s suborbital operations. This approach demonstrates that structured qualitative risk-management frameworks can effectively assess catastrophic hazards with limited empirical data and reduce risks to acceptable levels without imposing excessive costs on operators. To address existing safety and regulatory gaps, this study recommends: (1) establishing a defined regulatory framework with mandatory vehicle certification and legal protections for participants; (2) the adoption of risk-management methodologies such as ALARP and CBA by commercial operators; (3) developing FAA-AST– directed medical screening and training programs for spaceflight participants; (4) incorporating personal safety equipment, including breathing apparatus; and (5) fostering collaboration with established aerospace institutions such as NASA. Overall, the findings highlight the need for near-term policy action to support a safe, sustainable, and accountable evolution of suborbital space tourism.

Spindle cell carcinoma (SpCC) is an aggressive subtype of squamous cell carcinoma characterized by a biphasic pattern with both sarcomatous spindle cell and epithelial squamous cell components. It accounts for less than 3% of all head and neck cancers, with a male predominance, presenting in the 5th to 6th decades of life. The larynx is the most commonly affected site, with dysphagia being the most frequently presenting complaint. Hypopharyngeal involvement is uncommon, particularly in the postcricoid region. We present a 55-year-old male with a complaint of bilateral neck swellings without dysphagia. An exophytic growth on the postcricoid region of the hypopharynx was evident on laryngoscopy, and histopathology confirmed SpCC. A computed tomography (CT) scan showed necrotic cervical nodes, and chemotherapy was initiated for treatment.

Many species experience less pressure from herbivores, predators, or pathogens in their introduced range than in their native range. This phenomenon, known as enemy release, is one explanation for the success of introduced plant species worldwide. However, species experience enemy release to different extents, or not at all. Surprisingly, we have little understanding of what types of species or circumstances are associated with strong enemy release. We aimed to test whether ten defensive leaf traits that contribute to plants' palatability to aboveground herbivores can predict the level of enemy release they experience. Our study expands upon previous work, which found enemy release occurring across 16 plant species studied at 12 sites within their native (5 sites; European) and introduced (7 sites; Australian) ranges. Contrary to all predictions, we found no evidence that enemy release was related to ash content, C:N ratio, hair density, leaf dry matter content, leaf mass per area, cyanogen presence, lipid content, phenolic compounds, oxidative activity, or combined chemical, physical, and total defences. This result demonstrates the need to further assess other traits, or environmental variables that may contribute to enemy release, so that we may more accurately predict when and where it is most likely to occur. Finding that these defensive traits do not predict enemy release in our study system brings us a step closer to understanding the mechanisms underlying successful invasion, which is increasingly important in our rapidly changing world.

The relationship between myocardial injury after cardiac surgery (MICS), ischemia on electrocardiogram (ECG), and mortality is uncertain. In this study we aimed to determine whether potential ischemic ECG changes after cardiac surgery are associated with 30-day mortality. In a cohort of adults who underwent cardiac surgery, experts interpreted ECGs preoperatively; on postoperative days 0, 1, 2, and 3; and on the last day before discharge (59,539 total ECGs reviewed) for new potential ischemic ECG changes. Among 12,594 patients, 9097 (72.2%) had potential ischemic ECG changes; 259 (2.1%) died within 30 days after surgery. Among patients with troponin elevation meeting MICS criteria, in models adjusting for EuroSCORE II, the hazard ratio (HR) for 30-day mortality was 0.57 (95% confidence interval [CI] 0.35-0.94, P = 0.03) for new Q waves, 2.17 (95% CI 1.14-4.13, P = 0.02) for ST depression ≥ 2 mm, and 0.58 (95% CI 0.39-0.87, P = 0.007) for T-wave inversion 1-1.9 mm. ST elevation was not significantly associated with 30-day mortality. The only ECG change for which coronary artery bypass grafting (CABG) was an effect modifier was new left bundle branch block (LBBB), with an HR of 2.78 (95% CI 1.69-4.60, P = 0.0001) with CABG and an HR of 1.10 (95% CI 0.54-2.21, P = 0.27) without CABG (P value for interaction = 0.03). After cardiac surgery, potential ischemic ECG changes are common and have divergent associations with mortality. ST depression was associated with a higher risk of death, whereas new Q waves and T-wave inversions were associated with a lower risk of death. A new LBBB was associated with a higher risk of death only among patients who underwent CABG. Potential ischemic ECG changes are common after cardiac surgery and lack specificity for the diagnosis of myocardial infarction.

Abstract We give some criteria for the Lie algebra to be solvable, where is a ‐block of a finite group algebra, in terms of the action of an inertial quotient of on a defect group of .

BackgroundAdolescents and young adults in low-and middle-income countries (LMICs), face multiple barriers to accessing quality mental health care, shaped by cultural expectations, systemic gaps, and widespread stigma. In Nigeria, little is known about how these factors intersect within psychiatric inpatient settings. This study explored the lived experiences of adolescents and young adults receiving inpatient psychiatric care to inform more culturally responsive, family-engaged, and psychologically supportive models of care.MethodsUsing an Interpretative Phenomenological Approach, we conducted in-depth semi-structured interviews with 28 participants aged 13 to 28 years, all receiving care at a public psychiatric hospital in South-Eastern Nigeria. Participants were purposively sampled and represented a range of diagnostic categories. The hospital, serving a diverse catchment area, reflects a hybrid system of biomedical and traditional models of care. Interviews were conducted over nine months and analysed through iterative, reflexive engagement, supported by member checking to enhance credibility and contextual grounding.ResultsParticipants described a range of emotionally charged experiences, with stigma emerging as a major theme. Several reported social withdrawal, strained family dynamics, and shifts in how they were perceived by others. Relationships with peers in hospital varied, offering both connection and tension. Personal coping strategies, such as prayer, art, music, and peer dialogue were commonly described. Despite these efforts, many expressed a desire for consistent psychological support and greater engagement from staff. Hospital environments were viewed as both protective and limiting, with concerns raised about overcrowding, lack of privacy, and emotional neglect.ConclusionWhile the findings cannot be generalised, they offer important insights into the mental health journeys of young people within a Nigerian inpatient setting. Participants called for greater emotional and relational support, staff communication, and culturally sensitive care. These perspectives highlight areas for further research and service improvement in youth mental health provision across similar contexts.