2,835 research outputs found
Transverse instabilities of stripe domains in magnetic thin films with perpendicular magnetic anisotropy
Stripe domains are narrow, elongated, reversed regions that exist in magnetic
materials with perpendicular magnetic anisotropy. Stripe domains appear as a
pair of domain walls that can exhibit topology with a nonzero chirality. Recent
experimental and numerical investigations identify an instability of stripe
domains in the long direction as a means of nucleating isolated magnetic
skyrmions. Here, the onset and nonlinear evolution of transverse instabilities
for a dynamic stripe domain known as the bion stripe are investigated. Both
non-topological and topological variants of the bion stripe are shown to
exhibit a long-wavelength transverse instability with different characteristic
features. In the former, small transverse variations in the stripe's width lead
to a neck instability that eventually pinches the non-topological stripe into a
chain of two-dimensional breathers composed of droplet soliton pairs. In the
latter case, small variations in the stripe's center results in a snake
instability whose topological structure leads to the nucleation of dynamic
magnetic skyrmions and antiskyrmions as well as perimeter-modulated droplets.
Quantitative, analytical predictions for both the early, linear evolution and
the long-time, nonlinear evolution are achieved using an averaged Lagrangian
approach that incorporates both exchange (dispersion) and anisotropy
(nonlinearity). The method of analysis is general and can be applied to other
filamentary structures.Comment: 8 figures, 13 page
Preclinical Alzheimer's dementia:A useful concept or another dead end?
The term, preclinical dementia, was introduced in 2011 when new guidelines for the diagnosis of Alzheimer's dementia (AD) were published. In the intervening 11 years, many studies have appeared in the literature focusing on this early stage. A search conducted in English on Google Scholar on 06.23.2022 using the term "preclinical (Alzheimer's) dementia" produced 121, 000 results. However, the label is arguably more relevant for research purposes, and it is possible that the knowledge gained may lead to a cure for AD. The term has not been widely adopted by clinical practitioners. Furthermore, it is still not possible to predict who, after a diagnosis of preclinical dementia, will go on to develop AD, and if so, what the risk factors (modifiable and non-modifiable) might be. This Review/Theoretical article will focus on preclinical Alzheimer's dementia (hereafter called preclinical AD). We outline how preclinical AD is currently defined, explain how it is diagnosed and explore why this is problematic at a number of different levels. We also ask the question: Is the concept 'preclinical AD' useful in clinical practice or is it just another dead end in the Holy Grail to find a treatment for AD? Specific recommendations for research and clinical practice are provided
Music and lyric characteristics of popular Dutch funeral songs
This study compared the characteristics of 150 songs (Dutch lyrics, N = 47, English lyrics, N = 103), popular at Dutch funerals, to an equal number of non-funeral songs. The variables explored included those linked with the music (valence, energy, danceability, acousticness, key, and tempo); and lyrics, namely: linguistics-related (first-person singular/plural, second-person pronouns; past, present, future tense; expressed emotion (positive, negative words, and the discrete emotional categories anger, anxiety, sadness); and category words (those relating to family, friends, death, religion). Funeral music was lower in valence, energy, and danceability and higher in acousticness than non-funeral music. Furthermore, English funeral music lyrics contained more second-person pronouns and were more future-focused than comparison songs. Funeral lyrics were not particularly negative, but English texts contained more words relating to sadness. In conclusion, funeral music differs in severable notable respects from general popular songs that may reflect the special purpose of this music
A Comparison of Music Characteristics of Funeral Music from Croatia, the Netherlands, and the United Kingdom
Music forms an integral and essential part of funeral rituals worldwide, but has to date received little systematic research attention. Recent investigations into funeral music used in the Netherlands showed that it is lower in tempo and valence, less energetic, and more acoustic than popular music. Funeral music is also often in a major mode. The present study sought to replicate these findings for a Dutch (NL) funeral music sample and to expand upon previous knowledge by investigating the audio features provided by Spotify, namely: valence, energy, tempo, acousticness, instrumentalness, mode, and danceability for funeral music samples from Croatia (HR) and the United Kingdom (UK). First, values of music characteristics for funeral music used in HR, N = 388 pieces, NL, N = 500 pieces, and UK, N = 439 pieces, were compared to values of popular control music from each country separately. Previous findings were replicated: for HR, NL, and UK, funeral music displayed a similar pattern as described above. Second, the values of Spotify audio features for funeral music were compared between countries. Analyses revealed significant differences between NL/UK and HR, namely lower valence and energy and higher acousticness (only HR-UK) and instrumentalness for NL/UK compared to HR. Effect sizes were, however, small and are likely due to differences in music selections. These results suggest that, even though there is much diversity in music pieces and songs, funeral music within and across these European countries is more alike than different in terms of its audio characteristics
Restricted diet in a vulnerable native turtle, Malaclemys terrapin (Schoepff), on the oceanic islands of Bermuda
Diamondback Terrapins (Malaclemys terrapin) are native to Bermuda, presently inhabiting only four small brackish-water ponds. Their foraging ecology was investigated using direct observation, fecal analysis, and necropsy. They do not have as varied a diet as reported from their North American range. Small gastropods (<3 mm shell height) were found in 66.7% of fecal samples and made up 97.3% of animal material dry mass, thus dominating their diet. Scavenged fish and other vertebrates (19% of samples overall), plus terrestrial arthropods (14.3% of samples) were other common items. Polychaete worms and bivalves each occurred in less than 3% of fecal samples. Pond sediment was found in 74% of the samples, probably incidentally ingested while foraging (by oral dredging) for the gastropods. The distribution and abundance of arthropods and molluscs within the terrapins’ brackish-water environment were assessed in three different habitats; pond benthos, mangrove swamp, and grass-dominated marsh. These indicated that Bermuda’s terrapins do not fully exploit the food resources present. On Bermuda M. terrapin is basically a specialist microphagous molluscivore and mainly forages by deposit-feeding on gastropods living in soft sediments. This dietary restriction has made them particularly vulnerable to environmental contamination
Reversing microcrystalline tests: an analytical approach to recycling of microcrystals from drugs of abuse
A combined analysis of microcrystalline tests followed by LC-MS or GC-MS analysis is described. Microcrystalline tests are shown to be non-destructive as addition products formed were easily dissociated after the application of an appropriate solvent. Subsequent analysis of the sample was done to quantify the recovery of the drug. Examples were performed using the date rape drug γ-hydroxybutyrate (GHB) and the synthetic opioid methadone
Music Influences Ratings of the Affect of Visual Stimuli
This review provides an overview of recent studies that have examined how music influences the judgment of emotional stimuli, including affective pictures and film clips. The relevant findings are incorporated within a broader theory of music and emotion, and suggestions for future research are offered.Music is important in our daily lives, and one of its primary uses by listeners is the active regulation of one\u27s mood. Despite this widespread use as a regulator of mood and its general pervasiveness in our society, the number of studies investigating the issue of whether, and how, music affects mood and emotional behaviour is limited however. Experiments investigating the effects of music have generally focused on how the emotional valence of background music impacts how affective pictures and/or film clips are evaluated. These studies have demonstrated strong effects of music on the emotional judgment of such stimuli. Most studies have reported concurrent background music to enhance the emotional valence when music and pictures are emotionally congruent. On the other hand, when music and pictures are emotionally incongruent, the ratings of the affect of the pictures will in- or decrease depending on the emotional valence of the background music. These results appear to be consistent in studies investigating the effects of (background) music
Midwest Evaluation of the Adult Functioning of Former Foster Youth
The Midwest Evaluation of the Adult Functioning of Former Foster Youth (Midwest Study) is a prospective study that has been following a sample of young people from Iowa, Wisconsin, and Illinois as they transition out of foster care into adulthood. It is a collaborative effort involving Chapin Hall at the University of Chicago; Partners for Our Children at the University of Washington, Seattle; the University of Wisconsin Survey Center; and the public child welfare agencies in Illinois, Iowa, and Wisconsin.The Midwest Study provides a comprehensive picture of how foster youth are faring during this transition since the Foster Care Independence Act of 1999 became law. Foster youth in Iowa, Wisconsin, and Illinois were eligible to participate in the study if they had entered care before their 16th birthday, were still in care at age 17, and had been removed from home for reasons other than delinquency. Baseline survey data were collected from 732 study participants when they were 17 or 18 years old. Study participants were re-interviewed at ages 19 (n = 603), 21 (n = 591), and 23 or 24 (n = 602). A fifth wave of survey data will be collected when study participants are 25 or 26 years old.Because many of the questions Midwest Study participants were also asked as part of the National Longitudinal Study of Adolescent Health, it is possible to make comparisons between this sample of former foster youth and a nationally representative sample of young people in the general population. These comparisons indicate that young people who have aged out of foster care are faring poorly as a group relative to their peers across a variety of domains.The Midwest Study also presents a unique opportunity to compare the outcomes of young people from one state (i.e., Illinois) that allows foster youth to remain in care until their 21st birthday to the outcomes of young people from two other states (i.e., Iowa and Wisconsin) in which foster youth generally age out when they are 18 years old. The data suggest that extending foster care until age 21 may be associated with better outcomes, at least in some domains
PRE-COVID-19 PHYSICAL ACTIVITY STATUS DOES NOT PROTECT AGAINST REDUCTIONS IN POST-COVID-19 SYMPTOMS: A CORRELATION RELATIVISTIC ANALYSIS DURING THE LOCKDOWN
People who exhibit unhealthy lifestyle behaviours are at greater risk of severe disease outcomes, risk of hospitalisation and mortality when infected with COVID-19. Accordingly, it is suggested that those with higher levels of cardiorespiratory fitness and who engage in regular physical activity (PA) are associated with a reduced risk of adverse outcomes. Although improved physiological function may protect individuals against severe acute COVID-19 outcomes, it is unknown whether it offers protection against developing sustained symptom profile, known as post-acute COVID-19 syndrome or Long COVID. Affecting an estimated 2 million people in the UK and 144 million globally, Long COVID is challenging healthcare services with broader social and economic impacts. Accordingly, this project aimed to determine the impact of PA status on Long COVID. An online survey was developed Utilizing adapted versions of preexisting Patient Re-ports Outcome Measures (Qualtrics, Provo, Utah, United States). Participants self-reported PA status in line with the World Health Organisation guidelines and their pre- and post-COVID-19 health status and symptom profile. A Mann-Whitney U test was used to analyse between-group responses, and a Wilcoxon Signed Rank test was used to analyse within-group responses. The survey was completed by 381 participants, of which n=253 reported meeting or exceeding the recommended guidelines of PA. A significant difference was found between pre- and post-COVID-19 health, whilst a Mann-Whitney U test concluded that there was no significant difference between PA groups and post-COVID-19 health status. According to the results, increased PA and cardiorespiratory fitness might offer protection against severe disease outcomes in the acute phase of infection but this does not offer full protection against developing a long-term symptom profile and increased mechanistic understanding of the physiological determinants is needed to restore the pre-COVID-19 status and assist in the development of multi-disciplinary interventions. Article visualizations
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