Variability of Active Galactic Nuclei From Differential Photometry

The Seoul AGN Monitoring Project, or SAMP for short, is an international project (PI Jonghak Woo from Korea) with the goal of measuring the masses of black holes residing in the center of massive active galactic nuclei (AGNs). AGNs are some of the brightest objects in the universe. Their light is attributed to the accretion of material onto the black hole. However, these objects are too distant to spatially resolve the gravitational sphere of influence of the black hole directly. Instead, we use a technique called reverberation mapping which observes the variability of the AGN power-law continuum emission and the time-delayed response of gas clouds ionized by the AGN that orbit the black hole inside the so-called broad-line region (BLR). Knowing the speed of light, the observed delay can be translated into the size of the broad-line region. Including the width of the broad emission lines, which is a tracer of the velocity of the BLR clouds, we can estimate the mass of the black hole. Photometry of the AGN optical continuum emission gathered from the 1m Nickel telescope at Lick Observatory is combined with spectroscopy of the BLR of the same AGNs obtained with the 3m Shane telescope at Lick Observatory. Students at Cal Poly have been in charge of the 1m Nickel telescope observations from January 2017 to September 2019, by operating the 1m telescope remotely from Cal Poly. In this thesis, I will cover the process of obtaining these optical images and analyze the continuum variability of the AGNs. In total, I present light curves for 18 AGNs, all of which show at least some degree of variability, promising successful black hole mass measurements when combined with spectroscopy results

The molecular epidemiology of penicillin-susceptible Staphylococcus aureus bacteraemia in Australia and the reliability of diagnostic phenotypic susceptibility method to detect penicillin susceptibility

Staphylococcus was first identified by Sir Alexander Ogston in 1881 when he was investigating the cause of suppurative inflammation in post-operative human patients. Using a light microscope, Ogston observed the spherical nature of the bacterium arranged in clusters in pus collected from an abscess. He was able to demonstrate the bacterium was the cause of the abscess by injecting healthy guinea pigs with pus, which resulted in septicaemia with the presence of the bacterium in blood (1). Conceived by Ogston, the term ‘Staphylococcus’ is from the Greek words “staphyle” (σταφύλια) meaning grapes, and “kokkos” (κόκκος) meaning berry (2). The species name of Staphylococcus aureus, derived from the Latin word “aurum” for gold, was subsequently coined by Friedrich Julius Rosenbach due to the distinct golden yellow pigmented colonies produced by the bacterium (3)

Motivations of Play in MMORPGs

Every day, millions of people interact with each other in online environments known as Massively-Multiplayer Online Role-Playing Games (MMORPGs). MMORPG players, who on average are 26 years old, typically spend 22 hours a week in these environments. Articulating motivational differences among different users is the precursor to understanding the emergence of more complex behaviors and interactions in these environments, as well as providing a framework to differentiate one user from another. Such a framework provides the foundation to explore whether different sections of the demographic are motivated differently, and whether certain motivations are more highly correlated with usage patterns or in-game preferences or behaviors. The following paper describes a study that used online survey data to create an empirical model of player motivations in MMORPGs and how those resulting motivations correlate with demographic variables and usage patterns. Bartle’s (1996) Player Types is a well-known taxonomy of Multi-User Domain (MUD) users derived from his experiences in creating and managing MUDs. These 4 Types - Achievers, Socializers, Explorers, and Killers - each have different in-game preferences and motivations for using the MUD environment. For example, Explorers are users who are interested in understanding the mechanics and rules of the system as well as mapping out the world, while Socializers are users who enjoy chatting, interacting and role-playing with other users. Bartle’s model provides an important foundation in understanding the motivations of different players, however, it suffers from three significant weaknesses. First, the proposed components of each Type may not be highly correlated. Second, the proposed Types might be overlapping and not truly distinct Types. And finally, the purely theoretical model provides no way to assess users as to what Type they might be. To resolve these weaknesses and build a more solid foundation for understanding player motivations, an empirical analysis was performed. A list of 40 questions that related to player motivations was generated based on Bartle’s Types and anecdotal information from earlier surveys of MMORPG players. Examples of these statements are: How important is it to you to level up as quickly as possible? How much do you enjoy helping other players? How often do you make up stories and histories for your characters? The response option for every question was a 5-point uni-polar construct-specific scale. For example, - Not Important At All - Slightly Important - Moderately Important - Very Important - Tremendously Important Data was then collected from 3000 MMORPG players through online surveys publicized at online portals that catered to MMORPG players from several popular MMORPGs - EverQuest, Dark Age of Camelot, Ultima Online, and Star Wars Galaxies. A factor analysis was then performed on this data to separate the statements into clusters where items within each cluster were as highly correlated as possible while clusters themselves were as uncorrelated as possible. The methodology achieved three goals that overcame the inherent weaknesses of Bartle’s model. First, it ensured that the components of each motivation were indeed correlated. Second, it ensured that different motivations were indeed different. And finally, it would provide a way to assess player motivations. In a sense, this methodology was testing Bartle’s Types for validity and correcting for inherent problems with a purely theoretical model. One important theoretical distinction between Bartle’s types and the factors resulting this study is that Bartle argued that every player was predominantly motivated by one of the four types, whereas the factor model assumes that factors are uncorrelated and therefore it is possible for a player to score high on several factors. This is analogous to contemporary personality assessment tools (such as the Big-5). Just because someone scores high on Extraversion doesn’t mean they can’t also score high on Neuroticism. In other words, in the factor model, scoring high in one factor doesn’t exclude a player from any other factor, whereas Bartle’s model implicitly does so. Bartle’s model tries to categorize players into boxes. The factor model scores players on every factor. A factor analysis using principal components extraction produced 7 factors. All resulting factors had a Cronbach’s alpha of over .70. These factors were: 1) Achievement - The desire to advance the character as quickly as possible, as well as accumulate rare equipment and items, in order to become powerful within the context of the game. 2) Casual Social Interaction (Chat) - An interest in chatting and gossiping with other players. 3) Immersion - The desire to be immersed in a fantasy world and try out new roles and personalities with different characters. 4) Serious Social Interaction (Relationship) - An interest in forming strong, supportive relationships where personal issues can be shared. 5) Competition - The desire to challenge and compete with other players. In more extreme cases, the desire to annoy, manipulate or dominate other players. 6) Escapism - The interest in the virtual world derives from wanting to escape from the real world. 7) Explorer - The desire to explore the game’s mechanics and geography. By calculating the factor scores for the 3000 respondents, the data also allowed an understanding of how these motivations mapped onto gender and age differences as well as hours of play per week. T-tests on the motivation scores grouped by gender showed that male players were significantly more motivated by Competition and Achievement (p’s < .001, r’s = .26 & .19) while female players were significantly more motivated by Casual and Serious Social Interaction (p’s < .001, r’s = .10 & .26). Age was negatively correlated with Achievement (r = -.30), Casual Social Interaction (r = -.10) and Competition (r = -.34). And finally, the number of hours played per week was positively correlated with Achievement (r = .16), Serious Social Interaction (r = .12) and Escapism (r = .12). The empirical model developed in this study provides a solid foundation for future research in MMORPGs by providing a model to understand player motivations, a tool to assess those motivations, and thus also a means to understand usage patterns, in-game behaviors and demographic variables in relation to player motivations

Think-Act-Contribute (TAC) as a unique way to promote healthy living in Tuen Mun district

TAC adopted a model with three progressive learning processes: THINK, ACT & CONTRIBUTE. It aims to first prepare the community to understand the TAC concepts in different perspectives (THINK) of psychological, mental and social health. Then physical activity (ACT) will be taught through healthy exercise such as dancing and stretching. Lastly, Participants are encouraged to promote healthy exercise and knowledge in the community (Contribute) by joining the TAC Health Leaders Program. By sharing a similar mission as Tuen Mun Healthy City Limited, we cooperate and adopt the TAC model to spread healthy ideas in the community. Unlike ordinary exercise program, this project packaged regular exercise programs with health-related seminars and workshops. Also, Health leaders (TAC Health Leaders) trained as trainers to further promote healthy lifestyles and create a supportive environment in sustaining healthy lifestyles in Tuen Mun. In the aspect of Service-Learning, Lingnan students act as Health Leaders to create health awareness in the community such as primary and secondary schools while applying the service experience and knowledge into their academic studies

Sost and its paralog Sostdc1 coordinate digit number in a Gli3-dependent manner.

WNT signaling is critical in most aspects of skeletal development and homeostasis, and antagonists of WNT signaling are emerging as key regulatory proteins with great promise as therapeutic agents for bone disorders. Here we show that Sost and its paralog Sostdc1 emerged through ancestral genome duplication and their expression patterns have diverged to delineate non-overlapping domains in most organ systems including musculoskeletal, cardiovascular, nervous, digestive, reproductive and respiratory. In the developing limb, Sost and Sostdc1 display dynamic expression patterns with Sost being restricted to the distal ectoderm and Sostdc1 to the proximal ectoderm and the mesenchyme. While Sostdc1(-/-) mice lack any obvious limb or skeletal defects, Sost(-/-) mice recapitulate the hand defects described for Sclerosteosis patients. However, elevated WNT signaling in Sost(-/-); Sostdc1(-/-) mice causes misregulation of SHH signaling, ectopic activation of Sox9 in the digit 1 field and preaxial polydactyly in a Gli1- and Gli3-dependent manner. In addition, we show that the syndactyly documented in Sclerosteosis is present in both Sost(-/-) and Sost(-/-); Sostdc1(-/-) mice, and is driven by misregulation of Fgf8 in the AER, a region lacking Sost and Sostdc1 expression. This study highlights the complexity of WNT signaling in skeletal biology and disease and emphasizes how redundant mechanism and non-cell autonomous effects can synergize to unveil new intricate phenotypes caused by elevated WNT signaling

Les jeux vidéo en ligne, un miroir de la personnalité des internautes ?

Dans cet article, nous explorons la possibilité de détecter la personnalité des utilisateurs de jeux vidéo à partir de leur comportement dans le monde virtuel. Un questionnaire administre à 1 040 joueurs de World of Warcraft permet d'établir leur profil sociodémographique ainsi que leur personnalité grâce au modèle à cinq facteurs. Nous utilisons ensuite des logiciels de collecte de données automatisées pour suivre les comportements virtuels de ces mêmes joueurs pendant quatre mois, en mesurant quotidiennement 3 500 variables comportementales pour chacun de leurs personnages. Sur la base de cet échantillon, nous montrons que, malgré le sentiment populaire selon lesquels les jeux sont un échappatoire permettant de créer une nouvelle identité fantastique, la personnalité des joueurs persiste lorsqu'ils enfilent leur corps virtuel : les jeux vidéo en ligne sont en fait un miroir de la personnalité de leurs utilisateurs.In this article, we explore the possibility of inferring the personality of videogame players using traces of their online behavior. Survey data from 1,040 World of Warcraft players containing demographic and personality variables was paired with 3,500 behavioral metrics collected daily in the game world over a four-month period. Despite the popular belief that online games allow many forms of « identity play », our data shows that a gamer's offline personality remains surprisingly stable when they step into the virtual world. It therefore seems that online videogames can be a surprisingly reliable mirror of their users' personalities

Polar bear (Ursus maritimus) Migration from Maternal Dens in Western Hudson Bay

Migration is a common life history strategy among Arctic vertebrates, yet some of its aspects remain poorly described for some species. In February-March, post-parturient polar bears (Ursus maritimus) in western Hudson Bay, Canada, migrate from maternity den sites on land to the sea ice with three- to four-month-old cubs. We investigated this migration using data from 10 adult females fitted with satellite-linked global positioning system collars tracked in 2011 – 16. Directed movement towards the coast began on average on 1 March (range: 31 January to 23 March) and took a mean of 7.8 days to reach the coast. Bears traveled 18 to 100 km from their dens to the coast (mean = 63 km) at a mean rate of 6.7 km/d. Movements were highly directed, with an approximate northeast orientation, but did not follow the shortest path to the coast. Observed migration patterns were broadly similar to those previously documented, although mean departure date from dens was about four days earlier and mean movement rate was only 40% of that from the late 1990s. Given the sensitivity of polar bears to climate change, the phenology of denning may be a meaningful parameter for long-term monitoring.Parmi les vertébrés de l’Arctique, la migration constitue une stratégie de cycle biologique courante et pourtant, pour certaines espèces, certains des aspects de la migration sont toujours mal décrits. En février et en mars, les ours polaires (Ursus maritimus) de post-parturition de l’ouest de la baie d’Hudson, au Canada, migrent depuis leurs aires terrestres de mise bas vers la glace de mer avec leurs oursons de trois à quatre mois. Nous avons étudié cette migration en nous servant des données relatives à dix femelles adultes dotées de colliers satellitaires avec système de localisation GPS, données recueillies de 2011 à 2016. En moyenne, les déplacements dirigés vers la côte commençaient le 1er mars (étendue : du 31 janvier au23 mars) et pour se rendre jusqu’à la côte, il fallait en moyenne 7,8 jours. De leur aire de mise bas jusqu’à la côte, les ours parcouraient de 18 à 100 km (moyenne = 63 km) au taux moyen de 6,7 km/j. Les déplacements étaient fortement dirigés, avec une orientation approximative du nord-est, sans toutefois emprunter le chemin le plus court menant à la côte. Les modèles de migration observés ressemblaient beaucoup aux modèles déjà documentés, quoique la date de départ moyenne des aires de mise bas s’établissait à environ quatre jours plus tôt et que le taux de déplacement moyen ne correspondait qu’à 40 % du taux de la fin des années 1990. Compte tenu de la sensibilité des ours polaires au changement climatique, la phénologie de l’aire de mise bas pourrait constituer un paramètre significatif pour la surveillance à long terme

Brief Lifestyle Interventions for Prediabetes in Primary Care:A Service Evaluation

BACKGROUND: The increasing number of cases of prediabetes in the UK is concerning, particularly in Wales where there is no standard programme of support. The aim of the current service evaluation was to examine the effectiveness of brief lifestyle interventions on glucose tolerance in people at risk of developing type 2 diabetes. METHODS: In this pragmatic service evaluation clinical data on people deemed at risk of developing type 2 diabetes were evaluated from two GP clusters. Patients (n = 1207) received a single 15 to 30-min, face-to-face, consultation with a health care practitioner. Interventions were assessed by changes in HbA1c and distribution across the HbA1c ranges 12 months following intervention. Statistical significance of reversion to normoglycaemia and development of diabetes were assessed through comparison with expected rates without intervention. RESULTS: Between baseline and 12-month follow-up HbA1c fell from 43.85 ± 1.57 mmol/mol (6.16 ± 0.14%) to 41.63 ± 3.84 mmol/mol (5.96 ± 0.35%), a decrease of 2.22 mmol/mol (0.20%) (95% CI 2.01 (0.18%), 2.42 (0.22%); p < 0.0001). The proportion of people with normal glucose tolerance at 12 months (0.50 95%CI 0.47, 0.52) was significantly larger than the lower (0.06 (p < 0.0001) and the upper (0.19 (p < 0.0001)) estimates based on no intervention. CONCLUSION: Results indicate significant improvement in glucose tolerance across GP clusters. The brief intervention has the potential to offer a robust and effective option to support people at risk of developing type 2 diabetes. Further research in the form of a randomised trial is needed to confirm this and identify those likely to benefit most from this intervention

Amyotrophic Lateral Sclerosis: Proteins, Proteostasis, Prions, and Promises

Copyright 2020 McAlary, Chew, Lum, Geraghty, Yerbury and Cashman. Amyotrophic lateral sclerosis (ALS) is characterized by the progressive degeneration of the motor neurons that innervate muscle, resulting in gradual paralysis and culminating in the inability to breathe or swallow. This neuronal degeneration occurs in a spatiotemporal manner from a point of onset in the central nervous system (CNS), suggesting that there is a molecule that spreads from cell-to-cell. There is strong evidence that the onset and progression of ALS pathology is a consequence of protein misfolding and aggregation. In line with this, a hallmark pathology of ALS is protein deposition and inclusion formation within motor neurons and surrounding glia of the proteins TAR DNA-binding protein 43, superoxide dismutase-1, or fused in sarcoma. Collectively, the observed protein aggregation, in conjunction with the spatiotemporal spread of symptoms, strongly suggests a prion-like propagation of protein aggregation occurs in ALS. In this review, we discuss the role of protein aggregation in ALS concerning protein homeostasis (proteostasis) mechanisms and prion-like propagation. Furthermore, we examine the experimental models used to investigate these processes, including in vitro assays, cultured cells, invertebrate models, and murine models. Finally, we evaluate the therapeutics that may best prevent the onset or spread of pathology in ALS and discuss what lies on the horizon for treating this currently incurable disease