190 research outputs found

    Sperm death and dumping in Drosophila

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    Mating with more than one male is the norm for females of many species. In addition to generating competition between the ejaculates of different males, multiple mating may allow females to bias sperm use. In Drosophila melanogaster, the last male to inseminate a female sires approximately 80% of subsequent progeny. Both sperm displacement, where resident sperm are removed from storage by the incoming ejaculate of the copulating male, and sperm incapacitation, where incoming seminal fluids supposedly interfere with resident sperm, have been implicated in this pattern of sperm use. But the idea of incapacitation is problematic because there are no known mechanisms by which an individual could damage rival sperm and not their own. Females also influence the process of sperm use, but exactly how is unclear. Here we show that seminal fluids do not kill rival sperm and that any 'incapacitation' is probably due to sperm ageing during sperm storage. We also show that females release stored sperm from the reproductive tract (sperm dumping) after copulation with a second male and that this requires neither incoming sperm nor seminal fluids. Instead, males may cause stored sperm to be dumped or females may differentially eject sperm from the previous mating

    A Qualitative Study Exploring the Acceptability and Usability of the e-Prescribing Risk and Safety Evaluation (ePRaSE) Assessment Within English Hospitals

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    Copyright \ua9 2025 The Author(s). Objectives: The e-prescribing risk and safety evaluation (ePRaSE) tool was developed to support the evaluation of hospital e-prescribing (EP) systems. The tool uses fictitious patients alongside previously validated prescribing scenarios to detect whether these systems provide appropriate prescribing advice to users. We sought to evaluate the usability and acceptability of ePRaSE across different EP systems in England. Materials and Methods: NHS hospitals in England with live EP systems were invited to participate. A combination of observations and semi-structured interviews were used to explore participants\u27 perspectives on the acceptability and usability of ePRaSE throughout all stages of the tool development. The data were transcribed verbatim, coded, and analyzed using the Framework Approach. Results: The study was conducted over 2 periods: April-December 2019 and September 2022-January 2023. Thirty-two health care professionals across 22 different NHS hospitals participated in semi-structured interviews (n=25) and 13 observations (n=20) involving 11 different EP systems in total. The ePRaSE assessment was completed in 2 to 3 hours and participants described the tool as easy to use with clinically relevant prescribing tasks. However, some participants experienced difficulties inputting clinical data, such as laboratory results, due to restricted access to different parts of the electronic health record. Many participants suggested areas for further improvement such as capturing a broader range of implemented clinical decision support and requested more detailed feedback on the performance of their systems. Conclusions: EP system users found ePRaSE to be a useful and acceptable tool. Further refinement is desirable, particularly in recording EP system responses and providing detailed results to optimize EP systems for safety benefits

    Phenetic distances in the Drosophila melanogaster-subgroup species and oviposition-site preference for food components

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    Oviposition-site preferences (O.S.P.) have been investigated in females of six sibling species of the Drosophila melanogaster subgroup. O.S.P. were determined for standard food components and yeast genotypes. Females of all species showed a strong preference for complete medium and avoidance of pure agar as an egg-deposition site.\ud \ud Ecological trees of the species on the basis of rank correlations were constructed. In ‘no-choice’ situations they agree with phylogenetic trees obtained by different means but in ‘choice’ situations they do not agree too well.\ud \ud All species showed a high egg production on live yeast compared with standard medium (with killed yeast) and D. erecta females demonstrated discrimination between yeast genotypes. Niche breadth calculated from survival on the sterol mutant yeasts correlated fairly well with phylogenetic trees

    Spatiotemporal processing of somatosensory stimuli in schizotypy

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    Unusual interaction behaviors and perceptual aberrations, like those occurring in schizotypy and schizophrenia, may in part originate from impaired remapping of environmental stimuli in the body space. Such remapping is contributed by the integration of tactile and proprioceptive information about current body posture with other exteroceptive spatial information. Surprisingly, no study has investigated whether alterations in such remapping occur in psychosis-prone individuals. Four hundred eleven students were screened with respect to schizotypal traits using the Schizotypal Personality Questionnaire. A subgroup of them, classified as low, moderate, and high schizotypes were to perform a temporal order judgment task of tactile stimuli delivered on their hands, with both uncrossed and crossed arms. Results revealed marked differences in touch remapping in the high schizotypes as compared to low and moderate schizotypes. For the first time here we reveal that the remapping of environmental stimuli in the body space, an essential function to demarcate the boundaries between self and external world, is altered in schizotypy. Results are discussed in relation to recent models of 'self-disorders' as due to perceptual incoherence

    A simulation study to quantitatively assess the performance of electronic prescribing systems in English NHS Hospital Trusts

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    \ua9 2025. The Author(s). Prescribing errors are a source of preventable harm in healthcare, which may be mitigated using Electronic Prescribing (EP) systems. Anyone who routinely prescribes medication could benefit from digitally assisted automated checks to identify whether a prescription should potentially not be allowed (e.g. drug allergy). National Health Service (NHS) Trusts have implemented a range of EP systems; however, their performance has not hitherto been evaluated. We developed the web-based Electronic Prescribing Risk and Safety Evaluation (ePRaSE) tool, which comprises a bank of prescribing scenarios to evaluate the performance of EP systems. We solicited ePRaSE testing: 68 pharmacists from across 45 English NHS Trusts, utilising 13 different EP systems volunteered for the study. We found considerable variability in mitigation performance (systems correctly identifying risk of error when prescribing) across both NHS Trusts and EP systems. Moreover, we found that mitigation performance varied considerably across NHS Trusts using the same EP system, strongly suggesting there are opportunities to optimise performance within systems. The ePRaSE tool is effective in identifying variability in risk management between NHS Trusts and EP systems. Wider use of this tool may facilitate improvements in EP system configurations, thus minimising potential harm from prescribing errors

    Prior movement of one arm facilitates motor adaptation in the other

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    Many movements in daily life are embedded in motion sequences that involve more than one limb, demanding the motor system to monitor and control different body parts in quick succession. During such movements, systematic changes in the environment or the body might require motor adaptation of specific segments. However, previous motor adaptation research has focused primarily on motion sequences produced by a single limb, or on simultaneous movements of several limbs. For example, adaptation to opposing force fields is possible in unimanual reaching tasks when the direction of a prior or subsequent movement is predictive of force field direction. It is unclear, however, whether multi-limb sequences can support motor adaptation processes in a similar way. In the present study (38 females, 38 males), we investigated whether reaches can be adapted to different force fields in a bimanual motor sequence when the information about the perturbation is associated with the prior movement direction of the other arm. In addition, we examined whether prior perceptual (visual or proprioceptive) feedback of the opposite arm contributes to force field-specific motor adaptation. Our key finding is that only active participation in the bimanual sequential task supports pronounced adaptation. This result suggests that active segments in bimanual motion sequences are linked across limbs. If there is a consistent association between movement kinematics of the linked and goal movement, the learning process of the goal movement can be facilitated. More generally, if motion sequences are repeated often, prior segments can evoke specific adjustments of subsequent movements.Significance statementMovements in a limb's motion sequence can be adjusted based on linked movements. A prerequisite is that kinematics of the linked movements correctly predict which adjustments are needed. We show that use of kinematic information to improve performance is even possible when a prior linked movement is performed with a different limb. For example, a skilled juggler might have learned how to correctly adjust his catching movement of the left hand when the right hand performed a throwing action in a specific way. Linkage is possibly a key mechanism of the human motor system for learning complex bimanual skills. Our study emphasizes that learning of specific movements should not be studied in isolation but within their motor sequence context

    How does it feel to act together?

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    This paper on the phenomenology of joint agency proposes a foray into a little explored territory at the intersection of two very active domains of research: joint action and sense of agency. I explore two ways in which our experience of joint agency may differ from our experience of individual agency. First, the mechanisms of action specification and control involved in joint action are typically more complex than those present in individual actions, since it is crucial for joint action that people coordinate their plans and actions. I discuss the implications that these coordination requirements might have for the strength of the sense of agency an agent may experience for a joint action. Second, engagement in joint action may involve a transformation of agentive identity and a partial or complete shift from a sense of self-agency to a sense of we-agency. I discuss several factors that may contribute to shaping our sense of agentive identity in joint action

    Motor imagery enhances performance beyond the imagined action

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    Motor imagery is frequently utilized to improve the performance of specific target movements in sports and rehabilitation. In this study, we show that motor imagery can facilitate learning of not only the imagined target movements but also sequentially linked overt movements. Hybrid sequences comprising imagined and physically executed segments allowed participants to learn specific movement characteristics of the executed segments when they were consistently associated with specific imagined segments. Electrophysiological recordings revealed that the degree of event-related synchronization in the alpha and beta bands during a basic motor imagery task was correlated with imagery-evoked motor learning. Thus, both behavioral and neural evidence indicate that motor imagery's benefits extend beyond the imagined movements, improving performance in linked overt movements. This provides decisive evidence for the functional equivalence of imagined and overt movements and suggests applications for imagery in sports and rehabilitation

    Prior movement of one arm facilitates motor adaptation in the other

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    Many movements in daily life are embedded in motion sequences that involve more than one limb, demanding the motor system to monitor and control different body parts in quick succession. During such movements, systematic changes in the environment or the body might require motor adaptation of specific segments. However, previous motor adaptation research has focused primarily on motion sequences produced by a single limb, or on simultaneous movements of several limbs. For example, adaptation to opposing force fields is possible in unimanual reaching tasks when the direction of a prior or subsequent movement is predictive of force field direction. It is unclear, however, whether multi-limb sequences can support motor adaptation processes in a similar way. In the present study, we investigated whether reaches can be adapted to different force fields in a bimanual motor sequence when the information about the perturbation is associated with the prior movement direction of the other arm. In addition, we examined whether prior perceptual (visual or proprioceptive) feedback of the opposite arm contributes to force field-specific motor adaptation. Our key finding is that only active participation in the bimanual sequential task supports pronounced adaptation. This result suggests that active segments in bimanual motion sequences are linked across limbs. If there is a consistent association between movement kinematics of the linked and goal movement, the learning process of the goal movement can be facilitated. More generally, if motion sequences are repeated often, prior segments can evoke specific adjustments of subsequent movements

    A complex ePrescribing antimicrobial stewardship-based (ePAMS+) intervention for hospitals: mixed-methods feasibility trial results

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    \ua9 2024. The Author(s). BACKGROUND: Antibiotic resistant infections cause over 700,000 deaths worldwide annually. As antimicrobial stewardship (AMS) helps minimise the emergence of antibiotic resistance resulting from inappropriate use of antibiotics in healthcare, we developed ePAMS+ (ePrescribing-based Anti-Microbial Stewardship), an ePrescribing and Medicines Administration (EPMA) system decision-support tool complemented by educational, behavioural and organisational elements. METHODS: We conducted a non-randomised before-and-after feasibility trial, implementing ePAMS+ in two English hospitals using the Cerner Millennium EPMA system. Wards of several specialties were included. Patient participants were blinded to whether ePAMS+ was in use; prescribers were not. A mixed-methods evaluation aimed to establish: acceptability and usability of ePAMS+ and trial processes; feasibility of ePAMS+ implementation and quantitative outcome recording; and a Fidelity Index measuring the extent to which ePAMS+ was delivered as intended. Longitudinal semi-structured interviews of doctors, nurses and pharmacists, alongside non-participant observations, gathered qualitative data; we extracted quantitative prescribing data from the EPMA system. Normal linear modelling of the defined daily dose (DDD) of antibiotic per admission quantified its variability, to inform sample size calculations for a future trial of ePAMS+ effectiveness. RESULTS: The research took place during the SARS-CoV-2 pandemic, from April 2021 to November 2022. 60 qualitative interviews were conducted (33 before ePAMS+ implementation, 27 after). 1,958 admissions (1,358 before ePAMS+ implementation; 600 after) included 24,884 antibiotic orders. Qualitative interviews confirmed that some aspects of ePAMS+ , its implementation and training were acceptable, while other features (e.g. enabling combinations of antibiotics to be prescribed) required further development. ePAMS+ uptake was low (28 antibiotic review records from 600 admissions; 0.047 records per admission), preventing full development of a Fidelity Index. Normal linear modelling of antibiotic DDD per admission showed a residual variance of 1.086 (log-transformed scale). Unavailability of indication data prevented measurement of some outcomes (e.g. number of antibiotic courses per indication). CONCLUSIONS: This feasibility trial encountered unforeseen circumstances due to contextual factors and a global pandemic, highlighting the need for careful adaptation of complex intervention implementations to the local setting. We identified key refinements to ePAMS+ to support its wider adoption in clinical practice, requiring further piloting before a confirmatory effectiveness trial. TRIAL REGISTRATION: ISRCTN Registry ISRCTN13429325, 24 March 2022
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