2,081 research outputs found
PrEP use, sexual behaviour, and PrEP adherence among men who have sex with men living in Wales prior to and during the COVID-19 pandemic
Experiences of men who have sex with men when initiating, implementing, and persisting with HIV pre-exposure prophylaxis
Abstract Introduction HIV preâexposure prophylaxis (PrEP) involves the use of antiretroviral medication in HIVânegative individuals considered to be at risk of acquiring HIV. It has been shown to prevent HIV and has been available in Wales since July 2017. Measuring and understanding adherence to PrEP is complex as it relies on the simultaneous understanding of both PrEP use and sexual activity. We aimed to understand the experiences of men who have sex with men (MSM) living in Wales initiating, implementing and persisting with HIV PrEP. Methods We conducted semistructured interviews with MSM PrEP users in Wales who participated in a cohort study of PrEP use and sexual behaviour. Following completion of the cohort study, participants were invited to take part in a semistructured interview about their experiences of taking PrEP. We aimed to include both individuals who had persisted with and discontinued PrEP during the study. The interview topic guide was informed by the ABC taxonomy for medication adherence and the theory of planned behaviour. We analysed our data using reflexive thematic analysis. Results Twentyâone participants were interviewed, five having discontinued PrEP during the cohort study. The developed themes focused on triggers for initiating PrEP, habitual behaviour, drivers for discontinuation and engagement with sexual health services. Stigma surrounding both PrEP and HIV permeated most topics, acting as a driver for initiating PrEP, an opportunity to reduce discrimination against people living with HIV, but also a concern around the perception of PrEP users. Conclusion This is the first study to investigate PrEPâtaking experiences incorporating established medication adherence taxonomy. We highlight key experiences regarding the initiation, implementation and persistence with PrEP and describe how taking PrEP may promote positive engagement with sexual health services. These findings may be useful for informing PrEP rollout programmes and need to be explored in other key populations. Patient and Public Contribution PrEP users, in addition to PrEP providers and representatives of HIV advocacy and policy, were involved in developing the topic guide for this study
Between- and within-individual sociodemographic and psychological determinants of PrEP adherence among men who have sex with men prescribed a daily PrEP regimen in Wales
We investigated the determinants of daily PrEP use and coverage of condomless anal sex (CAS) by PrEP among men who
have sex with men in Wales, UK. We measured PrEP use by electronic monitors and CAS by secure online surveys. We
defned PrEP use based on daily medication cap openings and coverage as CAS episodes preceded byâ„3 days of PrEP use
and followed byâ„2 days of PrEP use. We included 57 participants (5463 observations). An STI diagnosis was associated
with lower PrEP use but also lower PrEP coverage. Older adults had higher PrEP use. A belief that other PrEP users took
PrEP as prescribed was associated with lower PrEP coverage. An STI diagnosis is an important cue for an intervention,
refecting episodes of high-risk sexual behaviour and low PrEP coverage. Other results provide a basis for the development
of an evidence-informed intervention for promoting coverage of PrE
Early impact of COVID-19 social distancing measures on reported sexual behaviour of HIV pre-exposure prophylaxis users in Wales
Objectives To describe the early impact of COVID-19 and associated control measures on the sexual behaviour of pre-exposure prophylaxis (PrEP) users in Wales.
Methods Data were obtained from an ecological momentary assessment study of PrEP use and sexual behaviour. Participants were individuals accessing PrEP through the National Health Service (NHS) sexual health clinics across four health boards in Wales. Weekly data documenting condomless sex in the preceding week were analysed between 03/02/2020 and 10/05/2020. The introduction of social distancing measures and changes to sexual health clinics in Wales occurred on the week starting 16/03/2020. Two-level logistic regression models were fitted to condomless sex (yes/no) over time, included an indicator for the week starting 16/03/2020, and were extended to explore differential associations by relationship status and sexual health clinic.
Results Data were available from 56 participants and included 697 person-weeks (89% of the maximum number that could have been obtained). On average, 42% of participants reported condomless sex in the period prior to the introduction of social distancing measures and 20% reported condomless sex after (OR=0.16, 95% CI 0.07 to 0.37, p<0.001). There was some evidence to suggest that this association was moderated by relationship status (OR for single participants=0.09, 95% CI 0.06 to 0.23; OR for not single participants=0.46, 95% CI 0.16 to 1.25).
Conclusions The introduction of social distancing measures and changes to PrEP services across Wales was associated with a marked reduction in reported instances of condomless sexual intercourse among respondents, with a larger reduction in those who were single compared with those who were not. The long-term impact of COVID-19 and associated control measures on this populationâs physical and mental health and well-being requires close examination
Sequential Effects in Judgements of Attractiveness: The Influences of Face Race and Sex
In perceptual decision-making, a personâs response on a given trial is influenced by their response on the immediately preceding trial. This sequential effect was initially demonstrated in psychophysical tasks, but has now been found in more complex, real-world judgements. The similarity of the current and previous stimuli determines the nature of the effect, with more similar items producing assimilation in judgements, while less similarity can cause a contrast effect. Previous research found assimilation in ratings of facial attractiveness, and here, we investigated whether this effect is influenced by the social categories of the faces presented. Over three experiments, participants rated the attractiveness of own- (White) and other-race (Chinese) faces of both sexes that appeared successively. Through blocking trials by race (Experiment 1), sex (Experiment 2), or both dimensions (Experiment 3), we could examine how sequential judgements were altered by the salience of different social categories in face sequences. For sequences that varied in sex alone, own-race faces showed significantly less opposite-sex assimilation (male and female faces perceived as dissimilar), while other-race faces showed equal assimilation for opposite- and same-sex sequences (male and female faces were not differentiated). For sequences that varied in race alone, categorisation by race resulted in no opposite-race assimilation for either sex of face (White and Chinese faces perceived as dissimilar). For sequences that varied in both race and sex, same-category assimilation was significantly greater than opposite-category. Our results suggest that the race of a face represents a superordinate category relative to sex. These findings demonstrate the importance of social categories when considering sequential judgements of faces, and also highlight a novel approach for investigating how multiple social dimensions interact during decision-making
Maternal nicotine exposure leads to decreased cardiac protein disulfide isomerase and impaired mitochondrial function in male rat offspring.
Smoking throughout pregnancy can lead to complications during gestation, parturition and neonatal development. Thus, nicotine replacement therapies are a popular alternative thought to be safer than cigarettes. However, recent studies in rodents suggest that fetal and neonatal nicotine exposure alone results in cardiac dysfunction and high blood pressure. While it is well known that perinatal nicotine exposure causes increased congenital abnormalities, the mechanisms underlying longer-term deficits in cardiac function are not completely understood. Recently, our laboratory demonstrated that nicotine impairs placental protein disulfide isomerase (PDI) triggering an increase in endoplasmic reticulum stress, leading us to hypothesize that this may also occur in the heart. At 3 months of age, nicotine-exposed offspring had 45% decreased PDI levels in the absence of endoplasmic reticulum stress. Given the association of PDI and superoxide dismutase enzymes, we further observed that antioxidant superoxide dismutase-2 levels were reduced by 32% in these offspring concomitant with a 26-49% decrease in mitochondrial complex proteins (I, II, IV and V) and tissue inhibitor of metalloproteinase-4, a critical matrix metalloprotease for cardiac contractility and health. Collectively, this study suggests that perinatal nicotine exposure decreases PDI, which can promote oxidative damage and mitochondrial damage, associated with a premature decline in cardiac function
Theory of differential inclusions and its application in mechanics
The following chapter deals with systems of differential equations with
discontinuous right-hand sides. The key question is how to define the solutions
of such systems. The most adequate approach is to treat discontinuous systems
as systems with multivalued right-hand sides (differential inclusions). In this
work three well-known definitions of solution of discontinuous system are
considered. We will demonstrate the difference between these definitions and
their application to different mechanical problems. Mathematical models of
drilling systems with discontinuous friction torque characteristics are
considered. Here, opposite to classical Coulomb symmetric friction law, the
friction torque characteristic is asymmetrical. Problem of sudden load change
is studied. Analytical methods of investigation of systems with such
asymmetrical friction based on the use of Lyapunov functions are demonstrated.
The Watt governor and Chua system are considered to show different aspects of
computer modeling of discontinuous systems
Psychometric Properties of an Adapted Stigma Scale and Experiences of Stigma Associated with HIV Pre-exposure Prophylaxis Use Among Men Who have Sex with Men: A Mixed Methods Study
Psychometric properties of an adapted stigma scale and experiences of stigma associated with hiv pre-exposure prophylaxis use among men who have sex with men: a mixed methods stud
Multi-UAV Allocation Framework for predictive crime deterrence and data acquisition
The recent decline in the number of police and security force personnel has raised a serious security issue that could lead to reduced public safety and delayed response to crimes in urban areas. This may be alleviated in part by utilizing micro or small unmanned aerial vehicles (UAVs) and their high-mobility on-board sensors in conjunction with machine-learning techniques such as neural networks to offer better performance in predicting times and places that are high-risk and deterring crimes. The key to the success of such operation lies in the suitable placement of UAVs. This paper proposes a multi-UAV allocation framework for predictive crime deterrence and data acquisition that consists of the overarching methodology, a problem formulation, and an allocation method that work with a prediction model using a machine learning approach. In contrast to previous studies, our framework provides the most effective arrangement of UAVs for maximizing the chance to apprehend offenders whilst also acquiring data that will help improve the performance of subsequent crime prediction. This paper presents the system architecture assumed in this study, followed by a detailed description of the methodology, the formulation of the problem, and the UAV allocation method of the proposed framework. Our framework is tested using a real-world crime dataset to evaluate its performance with respect to the expected number of crimes deterred by the UAV patrol. Furthermore, to address the engineering practice of the proposed framework, we discuss the feasibility of the simulated deployment scenario in terms of energy consumption and the relationship between data analysis and crime prediction
Exploring Older Adult Susceptibility to Fraudulent Computer Pop-Up Interruptions
© 2019, Springer International Publishing AG, part of Springer Nature. The proliferation of Internet connectivity and accessibility has been accompanied by an increase in cyber-threats, including fraudulent communications. Fake computer updates, which attempt to persuade people to download malicious software by mimicking trusted brands and/or instilling urgency, are one way in which fraudsters try to infiltrate systems. A recent study of young university students (M 18.52-years) found that when such pop-ups interrupt a demanding cognitive task, participants spent little time viewing them and were more likely to miss suspicious cues and accept these updates compared to when they were viewed without the pressure to resume a suspended task [1]. The aim of the current experiment was to test an older adult sample (N = 29, all >60 years) using the same paradigm. We predicted that they would be more susceptible to malevolent pop-ups [2]; trusting them more than younger adults (e.g., [3]), and would attempt to resume the interrupted task faster to limit forgetting of encoded items. Phase 1 involved serial recall memory trials interrupted by genuine, mimicked, and low authority pop-ups. During phase 2, participants rated messages with unlimited time and gave reasons for their decisions. It was found that more than 70% of mimicked and low authority pop-ups were accepted in Phase 1 vs ~80% genuine pop-ups (and these were all approximately 10% higher than [1]). This was likely due to a greater tendency to ignore or miss suspicious content when performing under pressure, despite spending longer with messages and reporting high awareness of scam techniques than younger adults. Older adult participants were more suspicious during Phase 2 performing comparably to the younger adults in [1]. Factors that may impact older adult decisions relating to fraudulent computer communications are discussed, as well as theoretical and practical implications
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