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Multipole strength distributions for isoscalar L≤2 transitions in 28Si have been extracted using 386-MeV inelastic α scattering at extremely forward angles, including 0°. Observed strength distributions are in good agreement with microscopic calculations for an oblate-deformed ground state. In particular, a large peak at an excitation energy of 17.7 MeV in the isoscalar giant monopole resonance strength is consistent with the calculations. [ABSTRACT FROM AUTHOR]

The isoscalar giant monopole resonance (ISGMR) strength distribution in 24 Mg has been determined from background-free inelastic scattering of 386-MeV α particles at extreme forward angles, including 0 ∘ . The ISGMR strength distribution has been observed for the first time to have a two-peak structure in a light-mass nucleus. This splitting of ISGMR strength is explained well by microscopic theory in terms of the prolate deformation of the ground state of 24 Mg. [ABSTRACT FROM AUTHOR]

Strength distributions for isoscalar giant resonances with multipolarity L=2 have been determined in 24Mg from "instrumental background-free" inelastic scattering of 386-MeV a particles at extreme forward angles, including 0°. The isoscalar E0, E1, and E2 strengths are observed to be 57±7%, 111.1+10.9%-7.2, and 148.6±7.3%, respectively, of their energy-weighted sum rules in the excitation energy range of 6 to 35 MeV. The isoscalar giant monopole (ISGMR) and quadrupole (ISGQR) resonances exhibit a prominent K splitting which is consistent with microscopic theory for a prolate-deformed ground state of 24Mg. For the ISGQR it is due to splitting of the three K components, whereas for the ISGMR it is due to its coupling to the K=0 component of the ISGQR. Deformation effects on the isoscalar giant dipole resonance are less pronounced, however. [ABSTRACT FROM AUTHOR]

Aging negatively affects the capacity of muscle stem cells (MuSCs) to regenerate muscle. In this issue of the JCI, Ancel, Michaud, and colleagues used a high-content imaging screen to identify nicotinamide and pyridoxine as promoters of MuSC function. The combination of the two compounds promoted MuSC function in vivo in aged mice and in primary cells isolated from older individuals. Furthermore, the two compounds were lower in the circulation of older men, paralleling decreases in lean mass and gait speed. These results advance the translational perspective of rejuvenating MuSC function through nutraceuticals.

Introduction : The BIOFIRE Joint Infection (JI) Panel is a diagnostic tool that uses multiplex-PCR testing to detect microorganisms in synovial fluid specimens from patients suspected of having septic arthritis (SA) on native joints or prosthetic joint infections (PJIs). Methods : A study was conducted across 34 clinical sites in 19 European and Middle Eastern countries from March 2021 to June 2022 to assess the effectiveness of the BIOFIRE JI Panel. Results : A total of 1527 samples were collected from patients suspected of SA or PJI, with an overall agreement of 88.4 % and 85 % respectively between the JI Panel and synovial fluid cultures (SFCs). The JI Panel detected more positive samples and microorganisms than SFC, with a notable difference on Staphylococcus aureus , Streptococcus species, Enterococcus faecalis , Kingella kingae , Neisseria gonorrhoeae , and anaerobic bacteria. The study found that the BIOFIRE JI Panel has a high utility in the real-world clinical setting for suspected SA and PJI, providing diagnostic results in approximately 1 h. The user experience was positive, implying a potential benefit of rapidity of results' turnover in optimising patient management strategies. Conclusion : The study suggests that the BIOFIRE JI Panel could potentially optimise patient management and antimicrobial therapy, thus highlighting its importance in the clinical setting., Competing Interests: At least one of the (co-)authors is a member of the editorial board of Journal of Bone and Joint Infection. The peer-review process was guided by an independent editor, and the authors also have no other competing interests to declare., (Copyright: © 2024 Stéphanie Pascual et al.)

Septic arthritis is a serious condition with significant morbidity and mortality, routinely diagnosed using culture. The FDA has recently approved the rapid molecular BioFire® Joint Infection Panel (BJIP) for synovial fluid. We aimed to evaluate the BJIP compared to culture and its potential use in patient management. A multicentre retrospective evaluation of BJIP was conducted in the UK and Ireland. Positive percent agreement (PPA) and negative percent agreement (NPA) were calculated between the BJIP and routine culture. A multidisciplinary team (MDT) discussion addressing the optimal or potential case use of the assay practice was facilitated. Three hundred ninety-nine surplus synovial fluid samples (~ 70% from native joints) from eight centres were processed using BJIP in addition to routine culture. An increased yield of positive results was detected using BJIP compared to routine culture (98 vs 83), giving an overall PPA of 91.6% and overall NPA of 93% for the BJIP compared to culture results. The BJIP detected resistant markers and additional organisms that could influence antibiotic choices including Neisseria gonorrhoeae and Kingella kingae. The MDT agreed that the assay could be used, in addition to standard methods, in adult and children patients with specialist advice use based on local needs. Rapid results from BJIP were assessed as having potential clinical impact on patient management. Organisms not included in the panel may be clinically significant and may limit the value of this test for PJI., (© 2022. The Author(s).)

Intracranial aneurysms are associated with disturbed velocity patterns, and chronic inflammation, but the relevance for these findings are currently unknown. Here, we show that (disturbed) shear stress induced by vortices is a sufficient condition to activate the endothelial NF-kB pathway, possibly through a mechanism of mechanosensor de-activation. We provide evidence for this statement through in-vitro live cell imaging of NF-kB in HUVECs exposed to different flow conditions, stochastic modelling of flow induced NF-kB activation and induction of disturbed flow in mouse carotid arteries. Finally, CFD and immunofluorescence on human intracranial aneurysms showed a correlation similar to the mouse vessels, suggesting that disturbed shear stress may lead to sustained NF-kB activation thereby offering an explanation for the close association between disturbed flow and intracranial aneurysms.

Objective: To explore the experiences of healthcare professionals working in falls prevention and memory assessment services in providing assessments and interventions for falls risk reduction in people with dementia., Design: This is a qualitative study using 19 semistructured interviews. Interviews were analysed through thematic analysis., Setting: Community-based falls and memory assessment services in the East Midlands, UK., Participants: Nurses (n=10), physiotherapists (n=5), occupational therapists (n=3) and a psychiatrist (n=1)., Results: Three substantive themes were identified: challenges posed by dementia, adaptations to make falls prevention appropriate for people with dementia and organisational barriers. Patients' poor recall, planning and increased behavioural risk associated with dementia were key problems. Healthcare professionals provided many suggestions on how to overcome these challenges, such as adapting exercise interventions by using more visual aids. Problems associated with cognitive impairment created a need for additional support, for instance longer interventions, and supervision by support workers, to enable effective intervention, yet limited resources meant this was not always achievable. Communication between mental and physical health teams could be ineffective, as services were organised as separate entities, creating a reliance on third parties to be intermediaries. Structural and organisational factors made it difficult to deliver optimal falls prevention for people living with dementia., Conclusions: Healthcare professionals experience challenges in providing falls prevention to people with dementia at the individual and organisational levels. Interventions can be adapted for people with dementia, but this requires additional resources and improved integration of services. Future research is needed to develop and test the effectiveness and cost-effectiveness of such services., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.)

Objective: To explore the perceptions of older people with mild dementia and mild cognitive impairment, and their family carers, about falling, falls risk and the acceptability of falls prevention interventions., Design: Qualitative study involving thematic analysis of semi-structured interviews with patient and relative dyads., Participants and Setting: 20 patient/ relative dyads recruited from Memory Assessment Services and Falls Prevention Services in the United Kingdom., Results: The findings are presented under four key themes: attitudes to falls, attitudes to falls prevention interventions, barriers and facilitators, and the role of relatives. Participants' attitudes to falls interventions were varied and sometimes conflicting. Some worried about falls, but many resisted identifying themselves as potential 'fallers', even despite having fallen, and rejected the idea of needing the help that structured interventions signify. Participants preferred to focus on coping in the present rather than anticipating, and preparing for, an uncertain future. Falls prevention interventions were acknowledged to be valuable in principle and if required in the future but often felt to be not necessary or appropriate at present., Conclusions: This study of how persons with cognitive impairment, and their relatives, view falls risk and prevention mirror findings relating to the wider population of older persons without dementia. Participants did not generally see falls prevention interventions as currently relevant to themselves. The challenge for clinicians is how to present interventions with understanding and respect for the older person's identity. They must identify and address goals that patients and relatives value. Simplistic or paternalistic approaches will likely fail. Individualised interventions which focus on maintaining independence and preserving quality of life are more likely to be acceptable by supporting a positive self-image for patients and their relatives.

Bifurcation aneurysms account for a large fraction of cerebral aneurysms and often present morphologies that render traditional endovascular treatments, such as coiling, challenging and problematic. Flow-diverter stents offer a potentially elegant treatment option for such aneurysms, but clinical use of these devices remains controversial. Specifically, the deployment of a flow-diverter device in a bifurcation entails jailing one or more potentially vital vessels with a low-porosity mesh designed to restrict the flow. When multiple device placement configurations exist, the most appropriate clinical decision becomes increasingly opaque. In this study, three bifurcation aneurysm geometries were virtually treated by flow-diverter device. Each aneurysm was selected to offer two possible device deployment positions. Flow-diverters similar to commercially available designs were deployed with a fast-deployment algorithm before transient and steady state computational fluid dynamics simulations were performed. Reductions in aneurysm inflow, mean wall shear stress and maximum wall shear stress, all factors often linked with aneurysm treatment outcome, were compared for different device configurations in each aneurysm. In each of the three aneurysms modelled, a particular preferential device placement was shown to offer superior performance with the greatest reduction in the flow metrics considered. In all the three aneurysm geometries, substantial variations in inflow reduction (up to 25.3%), mean wall shear stress reduction (up to 14.6%) and maximum wall shear stress reduction (up to 12.1%) were seen, which were all attributed to device placement alone. Optimal device placement was found to be non-trivial and highly aneurysm specific; in only one-third of the simulated geometries, the best overall performance was achieved by deploying a device in the daughter vessel with the highest flow rate. Good correspondence was seen between transient results and steady state computations that offered a significant reduction in simulation run time. If accurate steady state computations are combined with the fast-deployment algorithm used, the modest run time and corresponding hardware make a virtual treatment pipeline in the clinical setting a meaningful possibility.

Background and Purpose: Accurately and efficiently modeling the transport of angiographic contrast currently offers the best method of verifying computational fluid dynamics simulations and, with it, progress toward the lofty goal of prediction of aneurysm treatment outcome a priori. This study specifically examines the influence of estimated flow rate and contrast properties on such in silico predictions of aneurysm contrast residence and decay., Materials and Methods: Four experimental sidewall aneurysms were created in swine, with aneurysm contrast flow patterns and decay rates observed under angiography. A simplified computational fluid dynamics model of the experimental aneurysm was constructed from 3D angiography and contrast residence predicted a priori. The relative influence of a number of estimated model parameters (contrast viscosity, contrast density, and blood flow rate) on contrast residence was then investigated with further simulations., Results: Contrast infiltration and washout pattern were accurately predicted by the a priori computational fluid dynamics model; however, the contrast decay rate was underestimated by ∼25%. This error was attributed to the estimated parent vessel flow rate alone, and the effects of contrast viscosity and density on the decay rate were found to be inconsequential. A linear correlation between the parent vessel flow rate and the corresponding contrast decay rate was observed., Conclusions: In experimental sidewall aneurysms, contrast fluid properties (viscosity and density) were shown to have a negligible effect on variation in the modeled contrast decay rate. A strong linear correlation was observed between parent vessel flow rate and contrast decay over a physiologically reasonable range of flow rates., (© 2016 by American Journal of Neuroradiology.)

The use of a stand-alone flow diverter (FD) stent has demonstrated itself as an efficacious endovascular approach to intracranial aneurysm treatment. FD stents that are currently available adopt an interwoven braided design. The relatively low radial stiffness intrinsic to this design could cause difficulty in deployment and poor stent-wall apposition, leading to high complication rates. A new FD stent is proposed to overcome the problems of the interwoven FD stents. The new device is manufactured from a Nitinol tube through a laser-cutting technique, and its unique structure allows for both low porosity and high packaging efficiency. Computational simulation using Abaqus has been conducted to investigate the radial stiffness and longitudinal flexibility of the new device. The new device exhibits high radial stiffness when compared to interwoven FD stents and superior longitudinal flexibility. Results from on-going in-vivo experiments and CFD simulations have also demonstrated the efficacy of the new device as a FD stent., (Copyright © 2015 Elsevier Ltd. All rights reserved.)