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Properties of magnetic switchbacks in the near-sun solar wind
No full textMagnetic switchbacks are fluctuations in the solar wind in which the interplanetary magnetic field sharply deflects away from its background direction so as to create folds in magnetic field lines while remaining of roughly constant magnitude. The magnetic field and velocity fluctuations are extremely well correlated in a way corresponding to Alfvénic fluctuations propagating away from the Sun. For a background field which is nearly radial this causes an outwardly propagating jet to form. Switchbacks and their characteristic velocity jets have recently been observed to be nearly ubiquitous by Parker Solar Probe with in situ measurements in the inner heliosphere within 0.3 AU. Their prevalence, substantial energy content, and potentially fundamental role in the dynamics of the outer corona and solar wind motivate the significant research efforts into their understanding. Here we review the in situ measurements of these structures (primarily by Parker Solar Probe). We discuss how they are identified and measured, and present an overview of the primary observational properties of these structures, both in terms of individual switchbacks and their collective arrangement into “patches”. We identify both properties for which there is a strong consensus and those that have limited or qualified support and require further investigation. We identify and collate several open questions and recommendations for future studies
Achieving superior tensile and fatigue properties than conventional wrought state via hybrid additive-forging manufacturing
No full textAdditively manufactured materials typically contain undesired defects and microstructures. These defects reduce material performance and limit the adoption of the technique in production environments. In this work, we report a hybrid manufacturing strategy that integrates additive manufacturing with hot forging to achieve exceptional mechanical properties in Ti-6Al-4V. The resulting material exhibits improved tensile and fatigue properties compared to its purely additively manufactured and conventionally wrought counterparts. The control of thermal history and plastic flow is capable of healing defects and tailoring microstructure. A series of combined forging and heat treatment processes were undertaken to reveal correlations between fabrication parameters and the resulting microstructures and mechanical response. The underlying mechanisms of microstructure evolution were investigated through systematic and integrated experimental characterization, finite element modelling and mechanical tests. A generic component, representative of an aero-engine blade, was fabricated using this technology, demonstrating the huge promise of adopting this technique in practical applications
Beat-to-beat QT variability: a population study of the QT variability index composition
No full textBackground/Objectives: One of the topics of electrocardiographic risk factor studies is investigations of beat-to-beat QT interval variability. The seminal study that reported QT variability as a prognostic risk factor introduced the so-called QT variability index (QTVi). QTVi quantification relies not only on the variance of QT intervals but also on correction factors, including RR interval variance, heart rate, and overall QT interval duration. This study investigated the influence of all the measured factors on QTVi values. Methods: Long-term electrocardiograms (ECGs) were obtained from 251 healthy subjects (mean age 33.6 ± 9.1 years, 108 females) during repeated postural tests that involved supine, sitting, and standing positions maintained for 10 or 15 min. During each position, a 5-min ECG segment with a stable heart rate and without any ectopic disturbances was found. In these segments, standard deviations of normal-to-normal RR (NN) interval durations (SDNN) and of beat-to-beat QT interval durations (SDQT) were measured together with the means of NN and QT intervals. QTVi was subsequently calculated. For each subject, results obtained during each postural position were averaged. Results: In multivariable regression models, evaluated separately in female and male sex-subgroups of the population, QTVi values were significantly dependent on SDQT, SDNN, and mean NN intervals (all p < 0.001) but practically independent of mean QT interval durations. Conclusions: QTVi is significantly influenced by factors that are unrelated to the beat-to-beat changes in QT interval durations. This needs to be considered when interpreting QTVi values. In future studies, multivariable statistical models are needed to ensure that QTVi findings are independent of associated heart rate variability indices
Impact, barriers, and facilitators of blood culture diversion devices to reduce blood culture contamination and improve patient safety: a scoping review
No full textBlood culture contamination (BCC) is a frequent and costly challenge in clinical diagnostics. BCC leads to extended hospital stays, unnecessary antimicrobial therapy, diagnostic delays, and increased healthcare costs, sometimes exceeding $100,000 per case depending on the scope of analysis. It also contributes to environmental waste and reputational harm.
Blood culture diversion (BCD), particularly via blood culture diversion devices (BCDDs), has emerged as a promising strategy to reduce BCC. BCDDs divert initial blood flow likely contaminated with skin flora, thereby improving diagnostic accuracy.
This scoping review analysed 23 studies, including randomized controlled trials and observational designs. BCD was an effective way to reduce the rate of BCC. BCDDs consistently outperformed open diversion methods in reducing BCC rates. However, findings on their impact on antimicrobial usage, hospital length of stay, and cost-effectiveness varied. Some studies reported significant cost savings and reduced vancomycin use, while others showed minimal change.
Barriers to BCDD adoption include financial constraints, inconsistent definitions of BCC, and variable staff compliance. Enablers include positive user feedback, targeted training, and integration into national surveillance frameworks. Evidence gaps remain in comparative effectiveness, sustainability metrics, and behavioural factors influencing implementation.
The review recommends broader adoption of BCDDs, particularly in high-risk settings, emphasising the need for local data to identify where implementation will be most effective. It also calls for standardized definitions, improved surveillance, and further research into broader clinical, economic, and environmental outcomes
Perspectives on the future of skin-prosthetic interactions
No full textSkin is filled with a rich network of sensory neurons and consequently skin interaction with, and perception of the external environment, are a continual phenomenon experienced by all people in society. For medical devices such as prosthetics, the mechanical interaction between skin and the device is an essential aspect for device function, but it must be minimised to ensure continued skin health which is inherently intertwined with biological processes. Numerous factors influence the interface properties of skin. For example hydration, which influences skin morphology and composition, in turn influencing skin mechanics that may lead to tissue inflammation and skin injury. Here we review the current state-of-the-art in skin medical device tribology with a particular focus on skin-prosthetic interactions. We split this article into traditional approaches to skin friction and a biology first approach to skin friction, with a paradigm shift of skin as an engineered material. The field of tribology has historically been an interdisciplinary field comprising engineers, chemists and physicists, but future developments are needed in skin biology to drive meaningful change. We envisage that the integration of both clinical and biological perspectives will drive future innovations towards improved medical device interactions with the skin, when paired with engineering perspectives
Screening tools to identify a neurogenic cause for pelvic organ dysfunction: a scoping review
No full textBackground
Pelvic organ dysfunction can be an early sign of neurological disease, potentially preceding recognition of the underlying neurogenic mechanism. Screening tools are widely used in healthcare to aid early detection. Many tools exist for assessing pelvic organ symptoms, but it is unclear if any are designed to identify whether neurological disease is causing pelvic organ symptoms, nor whether there may be a potential neurogenic basis for such symptoms in the absence of prior neurological diagnosis.
Objective
To identify assessment and diagnostic tools used to evaluate pelvic organ symptoms in neurological disease and determine their intended purposes, including whether any are designed to evaluate likelihood of neurogenic basis.
Methods
A scoping review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) scoping review guidance. Searches of MEDLINE, CINAHL, and Embase databases included terms such as “assessment and screening tools,” “neurological conditions,” and “pelvic organ dysfunction.”
Results
From 1600 papers screened, 513 were included. Across these, 212 different tools were identified, covering a wide variety of uses. However, none were specifically developed to screen for a neurogenic cause of pelvic organ symptoms in patients with or without a prior neurological diagnosis.
Conclusions
There are currently no tools designed to establish neurogenic mechanisms underlying pelvic organ symptoms. For undiagnosed individuals, this type of tool would trigger prompt neurology review, potentially improving prognosis. Developing a screening tool focused on detecting neurogenic origins could support earlier recognition and management of many neurological conditions associated with pelvic organ dysfunction
Multidisciplinary team–guided management of severe aortic stenosis: five-year outcomes following TAVI versus conservative treatment
No full textObjective:
Multidisciplinary team (MDT) meetings are central to treatment decisions in aortic stenosis (AS), particularly for borderline or high-risk patients. This study evaluates long-term, real-world outcomes according to MDT selected management strategy within routine clinical practice in this clinically important patient group.
Methods:
We conducted a retrospective cohort study of all patients with severe AS discussed at a TAVI MDT at a tertiary UK centre between January 2014 and December 2016. Patients were categorised as TAVI or non-TAVI (conservatively managed). Demographic, clinical, and frailty data were collected, including Charlson Comorbidity Index (CCI), Clinical Frailty
Scale (CFS), and number of prescribed medications. Survival was analysed using Kaplan–Meier estimates and Cox proportional hazards modelling adjusted for age, sex, frailty, comorbidity burden, and medication count.
Results:
A total of 373 patients were included (TAVI = 178; non-TAVI = 195). Patients undergoing TAVI were younger (81.3 vs 83.5 years; p = 0.01) and less frail (CFS 3.9 vs 4.9; p < 0.01). Survival at one, two, and five
years was significantly higher following TAVI (87.6%, 74.7%, 44.9%) compared with conservative management (60.8%, 44.2%, 12.1%; p <0.001). Median survival was 53 months after TAVI versus 20 months without intervention. On multivariable analysis, TAVI was independently associated with reduced mortality (HR 0.38, 95% CI 0.28–0.50; p <0.001).
Conclusions:
In patients with severe AS discussed at MDT, TAVI was associated with a substantial and durable survival advantage compared with conservative
management. These findings highlight the poor prognosis of untreated severe AS and support systematic inclusion of conservatively managed
patients in interventional registries to better inform MDT deliberation and shared decision-making
Beyond the doctor’s office: a longitudinal study mapping women’s experiences of the maternal healthcare journey as a pathway to reducing maternal mortality in Nigeria
No full textObjectives
Nigeria has one of the highest maternal mortality burdens globally. Improving maternal outcomes requires a better understanding of how women experience care across pregnancy, childbirth, and the postnatal period. This study explored women’s maternal healthcare experiences across the perinatal continuum in Nigeria, with a focus on how challenges emerge and interact over time.
Design
Longitudinal qualitative study using patient journey mapping.
Setting
Public primary, secondary, and tertiary healthcare facilities in Abuja, Nigeria.
Participants
Twelve pregnant women were purposively sampled. Each woman participated in two rounds of in-depth interviews: once in late pregnancy and again 2-6 weeks postpartum. All participants completed both interview rounds.
Methods
Data were collected through 24 semi-structured in-depth interviews conducted longitudinally to capture changes in women’s experiences before and after childbirth. Interview guides were informed by existing maternal health frameworks. Transcripts were analysed using reflexive thematic analysis and organised across five stages of the maternal healthcare journey: awareness, consideration, access, treatment, and recovery.
Findings
This study introduces a five-stage framework: Awareness, Consideration, Access, Treatment, and Recovery, to comprehensively explore maternal healthcare experiences. The findings reveal systemic inefficiencies at every stage of the pregnancy journey, from limited awareness of pregnancy test kits to unreliable booking systems and inadequate postpartum mental health support. This study highlights how early-stage barriers cascade into later phases, unlike traditional research that focuses only on clinical interactions. This study emphasises the importance of maternal care accessibility and recovery support, moving beyond a treatment-centric lens.
Conclusion
This study presents a transformative framework for understanding maternal healthcare as a continuum of interconnected experiences. The research offers actionable insights to enhance maternal health outcomes through stage-specific strategies. The globally adaptable framework provides policymakers and healthcare practitioners with a roadmap to improve maternal healthcare systems in Nigeria and beyond. This holistic approach lays the foundation for reducing maternal mortality while ensuring equitable care for all
The American society of clinical psychopharmacology (ASCP) task force on the deprescribing of psychotropic medications for mood disorders: Delphi expert consensus
No full textThe American Society of Clinical Psychopharmacology (ASCP) convened a 45-member international expert task force to identify circumstances supporting the deprescribing of core psychotropic medications for major depressive disorder (MDD) and bipolar disorders. Three Delphi survey rounds plus a selective literature review identified points of consensus (predefined as >75% agreement) about when antidepressant, antipsychotic, mood stabilizer, and sedative-hypnotic deprescribing is warranted. Twenty of 32 statements (63%) achieved consensus across 7 thematic areas. In MDD, panelists favored discontinuing antidepressants when mechanisms of action are duplicative, adequate trials produce 3 lifetime episodes. In bipolar disorder, antidepressant deprescribing was favored in the setting of rapid cycling, mixed features, or emerging mania/hypomania symptoms; and discouraged if prior antidepressant cessation led to relapse. In nonpsychotic mood disorders, panelists favored deprescribing antipsychotics that caused significant weight gain or tardive dyskinesia over adding pharmacological antidotes. Deprescribing to achieve an eventual medication-free status was considered inappropriate in bipolar I but not necessarily bipolar II disorder. While individualized circumstances necessarily inform psychopharmacology management, clinical presentations that misalign with existing pharmacotherapies may signal the desirability of cautious deprescribing
Generating cisgenic sexing strains in insect pests
No full textInsect pest population control via sterile insect technique markedly benefits from separation by sex prior to release. To simplify this process, traditional genetics has been deployed to develop genetic sexing strains (GSSs) for several disease vectors and agricultural pests of vast economic significance, although very few are applied in the field due to associated fitness costs and instability. In this study, we generated a method to engineer cisgenic GSS (CGSS) in insects. We use CRISPR/Cas9-mediated homology-directed repair to seamlessly translocate a sex-specific alternatively spliced intron into a dominant phenotypic gene generating a genetically stable strain that enables sex-sorting by eye. To achieve this feat, we use Ceratitis capitata as our model and relied on the sex-specifically spliced intron of its endogenous transformer gene, which we seamlessly inserted a copy into the pupal colouration white pupae gene. This minimal modification resulted in the generation of a homozygous strain we term IMPERIAL that was genetically and phenotypically stable where all female pupae are brown while male pupae are white with overall good fitness. By minimally editing the genome, our novel CGSS approach can be applied to other pests that may aid more efficient and economically suitable pest control