Performance test of QU-fitting in cosmic magnetism study

QU-fitting is a standard model-fitting method to reconstruct distribution of magnetic fields and polarized intensity along a line of sight (LOS) from an observed polarization spectrum. In this paper, we examine the performance of QU-fitting by simulating observations of two polarized sources located along the same LOS, varying the widths of the sources and the gap between them in Faraday depth space, systematically. Markov Chain Monte Carlo (MCMC) approach is used to obtain the best-fit parameters for a fitting model, and Akaike and Bayesian Information Criteria (AIC and BIC, respectively) are adopted to select the best model from four fitting models. We find that the combination of MCMC and AIC/BIC works fairly well in model selection and estimation of model parameters in the cases where two sources have relatively small widths and a larger gap in Faraday depth space. On the other hand, when two sources have large width in Faraday depth space, MCMC chain tends to be trapped in a local maximum so that AIC/BIC cannot select a correct model. We discuss the causes and the tendency of the failure of QU-fitting and suggest a way to improve it.Comment: 8 pages, 9 figures, submitted to MNRA

The Ecosystem Approach: recovering rivers to help save the Southern Resident killer whales

The “ecosystem approach” to managing habitats is of growing interest in the world of conservation biology, with the realization that recovery of protected species ultimately relies on the health of their environment. In the case of the critically endangered Southern Resident Killer Whale (SRKW) population, prey depletion is a major threat to their survival. Research has shown that the SRKWs are highly dependent on Chinook salmon; thus the restoration of Chinook throughout the U.S. and Canada Pacific region is crucial for SRKW recovery. The significant decline of salmon abundance can be attributed to habitat loss and degradation throughout their range. Restoring Chinook requires recovery of their natal rivers and spawning grounds, which could include removing or breaching dams or other structures blocking access to historic habitat. For example, the Columbia/Snake River Basin historically supported average runs of 10 to 16 million salmon per year and has been reduced to only 2.5 million fish annually, much of which come from hatcheries. Restoration of this basin offers the best opportunity to increase wild salmon in the SRKWs’ coastal range; recovering salmon populations in multiple river systems could provide abundant and reliable prey for the SRKWs throughout their habitat. However, each river basin has unique challenges for salmon restoration, and dam breaching has been a controversial topic for decades. Here, we present a plan showing how an ecosystem focus highlighting the connection between orcas, salmon, and healthy rivers provides a fresh approach, while demonstrating the potential of ecosystem-based management for endangered species recovery. The prospective effect on the SRKWs is indicative of the far-reaching impacts of taking the “ecosystem approach.” While the long-term effects may take decades to realize, river restoration can have considerable short-term impacts for multiple species. Such knowledge is invaluable for restoration ecology and for the future of the SRKWs

Using DTAGs to understand sound use, behavior, and vessel and associated noise effects in Southern Resident killer whales

Prey availability and disturbance from vessels and noise are identified threats to the recovery of endangered Southern Resident killer whales. Vessels and noise can mask echolocation signals used to capture fish prey and/or disrupt foraging behavior with implications for energy acquisition. In the U.S., vessel regulations have been implemented since 2011 to protect killer whales from vessel disturbance, particularly given the extent of whale-watching activities in the Salish Sea. We utilized suction cup-attached digital acoustic recording tags (DTAGs), consisting of hydrophones and movement sensors, to measure received noise levels, understanding killer whale use of sound, and determine effects of vessels and noise on subsurface behavior. During the 29 tag deployments on individually identified killer whales, we collected detailed geo-referenced vessel data concurrently as conditions allowed, along with opportunistic observations of predation to validate feeding. Received noise levels (dB re 1microPa) were significantly different across years but not consistently lower after the implementation of vessel regulations. Of the vessel factors considered, both vessel count and speed, but not distance, explained differences in noise levels, which may reflect changes in whale-watching vessel practices after regulations implementation. Additionally, the analysis of data from these animal-borne tags allow us to better understand subsurface foraging behavior involving the use of sound, to quantify foraging rates at an individual level, and to understand detailed vessel and noise effects. The results, along with those of other related studies, inform conservation and management measures that aim to promote Southern Resident recovery

Characterization of spotted hyena, Crocuta crocuta microsatellite loci

We have isolated 10 polymorphic microsatellite loci in the spotted hyena,Crocuta crocuta.The loci displayed between eight and 14 alleles in a minimum of 12 individuals tested. These loci will be used to investigate relatedness within social groups, the genetic structure of populations, sexual selection, and mate choice in spotted hyenas

Mortality risk and social network position in southern resident killer whales (Orcinus orca): sex differences and the importance of salmon abundance

An individual\u27s ecological environment affects its mortality risk, which in turn has fundamental consequences for life-history evolution and population viability. In many species, social relationships are likely to be an important component of an individual\u27s environment, and therefore mortality risk. Here, we examine the relationship between social position and mortality risk in Southern resident killer whales (Orcinus orca) using over three decades of social and demographic data. We find that the social position of male, but not female, killer whales in their social unit predicts their mortality risk. More socially integrated males have a significantly lower risk of mortality than socially peripheral males, particularly in years of low salmon abundance, suggesting that social position mediates access to resources. Male killer whales are larger and require more resources than females, increasing their vulnerability to starvation in years of low salmon abundance. More socially integrated males are likely to have better access to social information and food-sharing opportunities which may enhance their survival in years of low prey abundance. Our results show that observable variation in the social environment is linked to variation in mortality risk. Furthermore, our results highlight the importance of considering sex differences in social effects on survival when developing conservation strategies for long-lived social mammals

E. coli O157 on Scottish cattle farms: evidence of local spread and persistence using repeat cross-sectional data

<b>Background</b><p></p> Escherichia coli (E. coli) O157 is a virulent zoonotic strain of enterohaemorrhagic E. coli. In Scotland (1998-2008) the annual reported rate of human infection is 4.4 per 100,000 population which is consistently higher than other regions of the UK and abroad. Cattle are the primary reservoir. Thus understanding infection dynamics in cattle is paramount to reducing human infections.<p></p> A large database was created for farms sampled in two cross-sectional surveys carried out in Scotland (1998 - 2004). A statistical model was generated to identify risk factors for the presence of E. coli O157 on farms. Specific hypotheses were tested regarding the presence of E. coli O157 on local farms and the farms previous status. Pulsed-field gel electrophoresis (PFGE) profiles were further examined to ascertain whether local spread or persistence of strains could be inferred.<p></p> <b>Results</b><p></p> The presence of an E. coli O157 positive local farm (average distance: 5.96km) in the Highlands, North East and South West, farm size and the number of cattle moved onto the farm 8 weeks prior to sampling were significant risk factors for the presence of E. coli O157 on farms. Previous status of a farm was not a significant predictor of current status (p = 0.398). Farms within the same sampling cluster were significantly more likely to be the same PFGE type (p < 0.001), implicating spread of strains between local farms. Isolates with identical PFGE types were observed to persist across the two surveys, including 3 that were identified on the same farm, suggesting an environmental reservoir. PFGE types that were persistent were more likely to have been observed in human clinical infections in Scotland (p < 0.001) from the same time frame.<p></p> <b>Conclusions</b><p></p> The results of this study demonstrate the spread of E. coli O157 between local farms and highlight the potential link between persistent cattle strains and human clinical infections in Scotland. This novel insight into the epidemiology of Scottish E. coli O157 paves the way for future research into the mechanisms of transmission which should help with the design of control measures to reduce E. coli O157 from livestock-related sources

Southern Resident killer whales: from captivity to conservation

The endangered Southern Resident killer whale (Orcinus orca) (SRKW) population remains the only killer whale population listed under the United States Endangered Species Act in U.S. waters since it was listed in 2005. In the 1960s and 70s, the population was reduced by approximately 40% following intensive efforts to capture individuals for a growing marine park captivity industry. The first Northwest killer whale census (1974) found just 70 remaining individuals in the SRKW community. This population has struggled to return to pre-capture numbers, and in the face of new threats including prey depletion, toxic contamination, and vessel effects, fewer than 80 individuals remain today. Over the last 40 years, this unique killer whale community has transitioned from targets of the captivity industry to one of the most iconic wild species of the Pacific Northwest, but is now desperately in need of meaningful and effective conservation efforts. As threats to this population have changed, environmental and advocacy groups have revised their strategies from a focus on separate issues to a recognition of the need for an ecosystem approach to ensure the long-term recovery and survival of these iconic killer whales. Recent research indicates that ecosystem-based efforts drive quicker recovery of ecosystems and endangered species. This innovative method has led to new partnerships with groups from disparate backgrounds working together to address multiple issues in the Pacific Northwest to recover the SRKWs and their habitat - in particular addressing the threat of prey depletion for the SRKWs by working for salmon restoration. By focusing on the role of whales in the ecosystem and their needs, we can increase conservation efforts for the SRKWs and demonstrate the potential of ecosystem-based management

Appreciative inquiry in medical education*

The practice of medicine, and also medical education, typically adopts a problem-solving approach to identify "what is going wrong" with a situation. However, an alternative is Appreciative Inquiry (AI), which adopts a positive and strengths-based approach to identify "what is going well" with a situation. The AI approach can be used for the development and enhancement of the potential of both individuals and organizations. An essential aspect of the AI approach is the generative process, in which a new situation is envisioned and both individual and collective strengths are mobilized to make changes to achieve the valued future situation. The AI approach has been widely used in the world of business and general education, but is has an exciting potential for medical education, including curriculum development, faculty development, supporting learners through academic advising and mentoring, but also for enhancing the teaching and learning of both individuals and groups. This AMEE Guide describes the core principles of AI and their practical application in medical education

Exploring the Ambulatory Transitional Care Experience from Residential Aged Care Facilities (RACF) to Ambulatory Care Services

Objective(s): To explore the transitional care journey through Ambulatory care Services (ACS) for older residents from Residential Aged Care Facilities (RACF). To develop a clearer understanding of older residents needs and any gaps in current services provided; and to inform the development of a model of care to improve the resident’s transitional care journey Study Design: A qualitative project design using extensive stakeholder engagement Method: The Ambulatory Care (AC) experience was explored through semi-structured interviews with residents and their carers to determine gaps in transitional care continuity. Focus groups with RACF and ACS staff were also utilized. Journey mapping was used to support anecdotal evidence. Results: Three residents and 2 carers were interviewed and a total of 40 RACF and ACS staff attended 5 focus groups. Principal Findings: Qualitative data analysis identified four main themes across the transition journey: Inconsistent and adhoc communication; Just waiting around; Is it doing more harm than good?; and Unmet expectations.Conclusion: The results of this study have highlighted shortcomings in the provision of quality care in this transitional care group of older clients. A collaborative approach across organizational boundaries is necessary to ensure the development of an integrated person centered model to ensure the best transition to ambulatory care for RACF residents exists