719 research outputs found
Glassy Transition and Aging in a Model without Disorder
We study the off-equilibrium relaxational dynamics of the Amit-Roginsky
field theory, for which the mode coupling approximation is exact. We
show that complex phenomena such as aging and ergodicity breaking are present
at low temperature, similarly to what is found in long range spin glasses. This
is a generalization of mode coupling theory of the structural glass transition
to off-equilibrium situations.Comment: 9 pages, 1 uuencoded figure, LaTex, preprint NORDITA 94/3
Healthy Outside-Healthy Inside: The Human Health & Well-being Benefits of Alberta\u27s Protected Areas - towards a benefits-based management agenda
This report details the results of an empirical study that examined perceived health and well-being motives and benefits among visitors to a sample of Alberta’s parks and protected areas. The study revealed several major findings with important policy and management implications. First, the human health and well-being benefits that the visitors expected to receive from visits were perceived to be a major personal motivation in the choice to visit Alberta protected areas. The most important motivation factors identified by respondents were psychological and emotional well-being (89.1% of visitors ranked this important), social well-being (88.3%), physical well-being (80.3%), and environmental well-being (79.4%). Second, the perceived benefits that visitors received from their protected areas experiences were substantial. The most frequently reported improvements were related to psychological and emotional (90.5%), social (85%), and physical well-being (77.6%). Interestingly, women perceived greater benefits than men associated with their visit, especially with respect to spiritual, social, and psychological and emotional well-being. Research findings substantiate the need for park agencies to better understand the motivations of visitors representing different social and population subgroups (e.g., youth, elderly, couples, etc.) in order to inform and develop policies and visitor experience programs in support of health and well-being related pursuits. Important policy and management implications for both park managers and health care professionals are highlighted
A review of paratuberculosis in dairy herds — Part 1: Epidemiology
Bovine paratuberculosis is a chronic infectious disease of cattle caused by Mycobacterium avium subspecies paratuberculosis (MAP). This is the first in a two-part review of the epidemiology and control of paratuberculosis in dairy herds. Paratuberculosis was originally described in 1895 and is now considered endemic among farmed cattle worldwide. MAP has been isolated from a wide range of non-ruminant wildlife as well as humans and non-human primates. In dairy herds, MAP is assumed to be introduced predominantly through the purchase of infected stock with additional factors modulating the risk of persistence or fade-out once an infected animal is introduced. Faecal shedding may vary widely between individuals and recent modelling work has shed some light on the role of super-shedding animals in the transmission of MAP within herds. Recent experimental work has revisited many of the assumptions around age susceptibility, faecal shedding in calves and calf-to-calf transmission. Further efforts to elucidate the relative contributions of different transmission routes to the dissemination of infection in endemic herds will aid in the prioritisation of efforts for control on farm
A review of paratuberculosis in dairy herds — Part 2: On-farm control
Bovine paratuberculosis is a chronic infectious disease of cattle, caused by Mycobacterium avium subspecies paratuberculosis (MAP). This is the second in a two-part review of the epidemiology and control of paratuberculosis in dairy herds. Several negative production effects associated with MAP infection have been described, but perhaps the most significant concern in relation to the importance of paratuberculosis as a disease of dairy cattle is the potential link with Crohn’s disease in humans. Milk is considered a potential transmission route to humans and it is recognised that pasteurisation does not necessarily eliminate the bacterium. Therefore, control must also include reduction of the levels of MAP in bulk milk supplied from dairy farms. There is little field evidence in support of specific control measures, although several studies seem to show a decreased prevalence associated with the implementation of a combined management and test-and-cull programme. Improvements in vaccination efficacy and reduced tuberculosis (TB) test interference may increase uptake of vaccination as a control option. Farmer adoption of best practice recommendations at farm level for the control of endemic diseases can be challenging. Improved understanding of farmer behaviour and decision making will help in developing improved communication strategies which may be more efficacious in affecting behavioural change on farm
A priori probability that a qubit-qutrit pair is separable
We extend to arbitrarily coupled pairs of qubits (two-state quantum systems)
and qutrits (three-state quantum systems) our earlier study (quant-ph/0207181),
which was concerned with the simplest instance of entangled quantum systems,
pairs of qubits. As in that analysis -- again on the basis of numerical
(quasi-Monte Carlo) integration results, but now in a still higher-dimensional
space (35-d vs. 15-d) -- we examine a conjecture that the Bures/SD (statistical
distinguishability) probability that arbitrarily paired qubits and qutrits are
separable (unentangled) has a simple exact value, u/(v Pi^3)= >.00124706, where
u = 2^20 3^3 5 7 and v = 19 23 29 31 37 41 43 (the product of consecutive
primes). This is considerably less than the conjectured value of the Bures/SD
probability, 8/(11 Pi^2) = 0736881, in the qubit-qubit case. Both of these
conjectures, in turn, rely upon ones to the effect that the SD volumes of
separable states assume certain remarkable forms, involving "primorial"
numbers. We also estimate the SD area of the boundary of separable qubit-qutrit
states, and provide preliminary calculations of the Bures/SD probability of
separability in the general qubit-qubit-qubit and qutrit-qutrit cases.Comment: 9 pages, 3 figures, 2 tables, LaTeX, we utilize recent exact
computations of Sommers and Zyczkowski (quant-ph/0304041) of "the Bures
volume of mixed quantum states" to refine our conjecture
Mobility and Cognition in Seniors. Report from the 2008 Institute of Aging (CIHR) Mobility and Cognition Workshop
Background
The annual Scientific Meeting of the Canadian Association on Gerontology was held on October 24 and 25, 2008 in London, Ontario. Prior to the annual meeting, mobility and cognition experts met on October 23, 2008 to engage in a pre-conference workshop.
Methods
Discussions during the workshop addressed novel areas of research and knowledge and research gaps pertaining to the interaction between mobility and cognition in seniors.
Results
Workshop presenters moved from the neuromuscular, biomechanics, and neurology of gait impairments, and falls through the role of cognition and mood on mobility regulation to the whole person in the environment. Research gaps were identified.
Conclusions
Despite a consensus that mobility and cognition are increasingly correlated as people age, several gaps in our understanding of mechanisms and how to assess the interaction were recognized. The gaps originally identified in 2008 are still pertinent today. Common and standardized assessments for “mobility and cognition” are still not in place in current practice. Interventions that target mobility and cognitive decline as a single entity are still lacking
Effects of vitamin D as a regulator of androgen intracrinology in LNCAP prostate cancer cells
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