Codeveloping and Evaluating a Campaign to Reduce Dementia Misconceptions on Twitter: Machine Learning Study.

Background: Dementia misconceptions on Twitter can have detrimental or harmful effects. Machine learning (ML) models codeveloped with carers provide a method to identify these and help in evaluating awareness campaigns.

Objective: This study aimed to develop an ML model to distinguish between misconceptions and neutral tweets and to develop, deploy, and evaluate an awareness campaign to tackle dementia misconceptions.

Effects of categorical and numerical feedback on category learning.

Real-world learning signals often come in the form of a continuous range of rewards or punishments, such as receiving more or less money or other reward. However, in laboratory studies, feedback used to examine how humans learn new categories has almost invariably been categorical in nature (i.e.

Investigation of Carers' Perspectives of Dementia Misconceptions on Twitter: Focus Group Study.

Background: Dementia misconceptions on social media are common, with negative effects on people with the condition, their carers, and those who know them. This study codeveloped a thematic framework with carers to understand the forms these misconceptions take on Twitter.

Objective: The aim of this study is to identify and analyze types of dementia conversations on Twitter using participatory methods.

Neural regions associated with gain-loss frequency and average reward in older and younger adults.

Research on the biological basis of reinforcement-learning has focused on how brain regions track expected value based on average reward. However, recent work suggests that humans are more attuned to reward frequency. Furthermore, older adults are less likely to use expected values to guide choice than younger adults.

Preliminary effects of prefrontal tDCS on dopamine-mediated behavior and psychophysiology.

The ability to manipulate dopamine in vivo through non-invasive, reversible mechanisms has the potential to impact clinical, translational, and basic research. Recent PET studies have demonstrated increased dopamine release in the striatum after bifrontal transcranial direct current stimulation (tDCS). We sought to extend this work by examining whether bifrontal tDCS could demonstrate an effect on behavioral and physiological correlates of subcortical dopamine activity.

Acute stress enhances tolerance of uncertainty during decision-making.

Acute stress has been shown to influence reward sensitivity, feedback learning, and risk-taking during decision-making, primarily through activation of the hypothalamic pituitary axis (HPA). However, it is unclear how acute stress affects decision-making among choices that vary in their degree of uncertainty. To address this question, we conducted two experiments in which participants repeatedly chose between two options-a high-uncertainty option that offered highly variable rewards but was advantageous in the long-term, and a low-uncertainty option that offered smaller yet more consistent rewards.

Learning reward frequency over reward probability: A tale of two learning rules.

Learning about the expected value of choice alternatives associated with reward is critical for adaptive behavior. Although human choice preferences are affected by the presentation frequency of reward-related alternatives, this may not be captured by some dominant models of value learning, such as the delta rule. In this study, we examined whether reward learning is driven more by learning the probability of reward provided by each option, or how frequently each option has been rewarded, and assess how well models based on average reward (e.

Acute stress improves long-term reward maximization in decision-making under uncertainty.

Acute stress influences reward-seeking tendencies and risky decision-making. However, it is unclear how acute stress influences decision-making in situations in which individuals must learn to either maximize long-term or immediate rewards from experience. Consequently, this study sought to investigate whether acute stress enhances salience of small, immediate or large, delayed rewards on decision-making under uncertainty.

Gender differences in preference for reward frequency versus reward magnitude in decision-making under uncertainty.

Extensive research has focused on gender differences in intertemporal choices made from in which participants must choose from multiple options that are specified without ambiguity. However, there has been limited work examining gender differences in intertemporal choices made from in which the possible payoffs among choice alternatives are not initially known and can only be gained from experience. Other work suggests that females attend more to reward , whereas males attend more to reward .

Ticking boxes or meaningful partnership - The experience of lay representation, participant and study partner involvement in Brains for Dementia Research.

Brains for Dementia Research is a planned brain donation project with serial assessments during life. Lay input helped conceive and shape Brains for Dementia Research and over time a growing number of lay volunteers have engaged with the project in almost all areas of activity. Lay representatives serve on the management and tissue banking committees, have spoken at recruitment and team events, and have reviewed all public and participant facing communications.

A Case of Divergent Predictions Made by Delta and Decay Rule Learning Models.

The Delta and Decay rules are two learning rules used to update expected values in reinforcement learning (RL) models. The delta rule learns rewards, whereas the decay rule learns rewards for each option. Participants learned to select between pairs of options that had reward probabilities of .

Low back cutaneous vibration and its effect on trunk postural control.

The current study investigated the effects of a low back pain (LBP) vibration modality on trunk motor control. Trunk repositioning error and responses to a sudden loading trunk perturbation were evaluated pre- and post-vibration (15min vibration exposure while sitting on a standard chair) as well as when concurrent cutaneous low back vibration was applied. Only minor effects were observed post-vibration when compared to pre-vibration.

Geographic variation in fasciotomy during operative management of tibia fractures.

Background: Diagnosis and treatment of acute or impending compartment syndrome (ACS) remains a clinical challenge. ACS is a clinical diagnosis, and may be associated with variation in its definition, as well as individual threshold for fasciotomy. We examined regional and state variation in rates of lower extremity fasciotomy associated with operatively managed tibia fractures.

African American community leaders' policy recommendations for reducing racial disparities in HIV infection, treatment, and care: results from a community-based participatory research project in Philadelphia, Pennsylvania.

African Americans account for 45% of new HIV infections in the United States. Little empirical research investigates African American community leaders' normative recommendations for addressing these disparities. Philadelphia's HIV infection rate is 5 times the national average, nearly 70% of new infections are among African Americans, and 2% of African Americans in Philadelphia are living with HIV/AIDS.

Prevalence and predictors of concurrent sexual partnerships in a predominantly African American population in Jackson, Mississippi.

Concurrent sexual partnerships, or sexual partnerships that overlap in time, have been associated with HIV and sexually transmitted infections (STI). How best to measure concurrency and the personal characteristics and predictors of concurrency are not yet well understood. We compared two frequently used concurrency definitions, including a self-reported measure based on participant response regarding overlapping sex with partners, and the UNAIDS measure based on overlapping dates of last sex and intention to have sex again.

What's God got to do with it? Engaging African-American faith-based institutions in HIV prevention.

African-Americans are disproportionately infected and affected by HIV/AIDS. Although faith-based institutions play critical leadership roles in the African-American community, the faith-based response to HIV/AIDS has historically been lacking. We explore recent successful strategies of a citywide HIV/AIDS awareness and testing campaign developed in partnership with 40 African-American faith-based institutions in Philadelphia, Pennsylvania, a city with some of the USA's highest HIV infection rates.

The impacts of AIDS movements on the policy responses to HIV/AIDS in Brazil and South Africa: a comparative analysis.

Brazil and South Africa were among the first countries profoundly impacted by the HIV/AIDS epidemic and had similar rates of HIV infection in the early 1990s. Today, Brazil has less than 1% adult HIV prevalence, implemented treatment and prevention programmes early in the epidemic, and now has exemplary HIV/AIDS programmes. South Africa, by contrast, has HIV prevalence of 18% and was, until recently, infamous for its delayed and inappropriate response to the HIV/AIDS epidemic.

African American patient experiences with a rapid HIV testing program in an urban public clinic.

Background: Of 1174 new human immunodeficiency virus (HIV) cases diagnosed in Philadelphia, Pennsylvania, in 2008, a total of 771 (66%) were among African Americans. Philadelphia recently introduced a citywide rapid HIV testing program in public clinics.

Methods: We conducted a qualitative study among 60 African Americans undergoing rapid HIV testing in one of Philadelphia's public clinics located in a zip code with high HIV incidence.

Concurrent sexual partnerships among African American women in Philadelphia: results from a qualitative study.

Background: African American women are disproportionately affected by HIV/AIDS. Concurrent sexual partnerships may contribute to racial disparities in HIV infection. Little is known about attitudes and practices related to concurrency among African American women, or the social, structural and behavioural factors influencing concurrency.

Keeping the faith: African American faith leaders' perspectives and recommendations for reducing racial disparities in HIV/AIDS infection.

In Philadelphia, 66% of new HIV infections are among African Americans and 2% of African Americans are living with HIV. The city of Philadelphia has among the largest numbers of faith institutions of any city in the country. Although faith-based institutions play an important role in the African American community, their response to the AIDS epidemic has historically been lacking.

A pilot study of emergency medical technicians' field assessment of intoxicated patients' need for ED care.

Objective: Alcohol-intoxicated individuals account for a significant proportion of emergency department care and may be eligible for care at alternative sobering facilities. This pilot study sought to examine intermediate-level emergency medical technician (EMT) ability to identify intoxicated individuals who may be eligible for diversion to an alternative sobering facility.

Methods: Intermediate-level EMTs in an urban fire department completed patient assessment surveys for individual intoxicated patients between May and August 2010.

Social, structural and behavioral drivers of concurrent partnerships among African American men in Philadelphia.

African Americans face disproportionately higher risks of HIV infection. Concurrent sexual relationships, or sexual partnerships that overlap in time, are more common among African Americans than individuals of other races and may contribute to racial disparities in HIV infection. However, little is known about attitudes, norms and practices among individuals engaged in concurrent partnerships.

An evaluation of a routine opt-out rapid HIV testing program in a Rhode Island jail.

There is an increased prevalence of HIV among incarcerated populations. We conducted a rapid HIV testing pilot program using oral specimens at the Rhode Island Department of Corrections (RIDOC) jail. Detainees (N = 1,364) were offered rapid testing upon jail entrance and 98% completed testing.