519 research outputs found
The impact of The Warehouse on New Zealand small towns: A discussion paper with specific reference to Maori
This discussion paper is based on empirical material looking at the social impact of The Warehouse (TW) on small town NZ. The results of this research show that Māori have a more positive orientation to The Warehouse than the non-Māori population. This paper provides some explanations of why this could be the case in small town New Zealand. The discussion paper suggests that large-format retail researchers need to be more careful when arguing that large-format retailers negatively affect small towns: the impact of their entry depends on socio-economic factors and the ethnic circumstances of various groups in the community and their outlying areas
Farmers’ Markets as Social Economy Drivers of Local Food Systems: Phases I and II
There is growing interest in the re-localization of food systems. Farmers’ markets are important and increasingly prevalent sites of economic and social exchange in the evolution of local food systems. Little is understood, however, about the role of farmers’ markets in fostering increased local production and consumption, or the broader impacts of these social economy enterprises on the communities (both urban and rural) and regions with which they are associated. This research project over two phases will examine and compare the current and potential role of farmers’ markets in British Columbia and Alberta, Canada, as social economy drivers for local food systems.BC-Alberta Social Economy Research Alliance (BALTA) ; Social Sciences and Humanities Research Council of Canada (SSHRC
Self-esteem depends on beliefs about the rate of change of social approval
A major challenge in understanding the neurobiological basis of psychiatric disorders is rigorously quantifying subjective metrics that lie at the core of mental illness, such as low self-esteem. Self-esteem can be conceptualized as a ‘gauge of social approval’ that increases in response to approval and decreases in response to disapproval. Computational studies have shown that learning signals that represent the difference between received and expected social approval drive changes in self-esteem. However, it is unclear whether self-esteem based on social approval should be understood as a value updated through associative learning, or as a belief about approval, updated by new evidence depending on how strongly it is held. Our results show that belief-based models explain self-esteem dynamics in response to social evaluation better than associative learning models. Importantly, they suggest that in the short term, self-esteem signals the direction and rate of change of one’s beliefs about approval within a group, rather than one’s social position
Model for Gravitational Interaction between Dark Matter and Baryons
We propose a phenomenological model where the gravitational interaction
between dark matter and baryons is suppressed on small, subgalactic scales. We
describe the gravitational force by adding a Yukawa contribution to the
standard Newtonian potential and show that this interaction scheme is
effectively suggested by the available observations of the inner rotation
curves of small mass galaxies. Besides helping in interpreting the cuspy
profile of dark matter halos observed in N-body simulations, this potential
regulates the quantity of baryons within halos of different masses.Comment: 4 pages, 2 figures, final versio
Automating Vascular Shunt Insertion with the dVRK Surgical Robot
Vascular shunt insertion is a fundamental surgical procedure used to
temporarily restore blood flow to tissues. It is often performed in the field
after major trauma. We formulate a problem of automated vascular shunt
insertion and propose a pipeline to perform Automated Vascular Shunt Insertion
(AVSI) using a da Vinci Research Kit. The pipeline uses a learned visual model
to estimate the locus of the vessel rim, plans a grasp on the rim, and moves to
grasp at that point. The first robot gripper then pulls the rim to stretch open
the vessel with a dilation motion. The second robot gripper then proceeds to
insert a shunt into the vessel phantom (a model of the blood vessel) with a
chamfer tilt followed by a screw motion. Results suggest that AVSI achieves a
high success rate even with tight tolerances and varying vessel orientations up
to 30{\deg}. Supplementary material, dataset, videos, and visualizations can be
found at https://sites.google.com/berkeley.edu/autolab-avsi
Model-Dependence of Shapiro Time Delay and the "Speed of Gravity/Speed of Light" Controversy
Fomalont and Kopeikin have recently succeeded in measuring the
velocity-dependent component of the Shapiro time delay of light from a quasar
passing behind Jupiter. While there is general agreement that this observation
tests the gravitomagnetic properties of the gravitational field, a controversy
has emerged over the question of whether the results depend on the speed of
light, , or the speed of gravity, . By analyzing the Shapiro time delay
in a set of ``preferred frame'' models, I demonstrate that this question is
ill-posed: the distinction can only be made in the context of a class of
theories in which , and the answer then depends on the specific class
of theories one chooses. It remains true, however, that for a large class of
theories ``close enough'' to general relativity, the leading contribution to
the time delay depends on and not ; within this class, observations
are thus not yet accurate enough to measure the speed of gravity.Comment: 12 pages, LaTeX; v2: added discussion of present observational
limits, and of relative importance of various contributions to time delay;
new references; v3: minor clarifications in response to refere
Self-esteem depends on beliefs about the rate of change of social approval
A major challenge in understanding the neurobiological basis of psychiatric disorders is rigorously quantifying subjective metrics that lie at the core of mental illness, such as low self-esteem. Self-esteem can be conceptualized as a ‘gauge of social approval’ that increases in response to approval and decreases in response to disapproval. Computational studies have shown that learning signals that represent the difference between received and expected social approval drive changes in self-esteem. However, it is unclear whether self-esteem based on social approval should be understood as a value updated through associative learning, or as a belief about approval, updated by new evidence depending on how strongly it is held. Our results show that belief-based models explain self-esteem dynamics in response to social evaluation better than associative learning models. Importantly, they suggest that in the short term, self-esteem signals the direction and rate of change of one’s beliefs about approval within a group, rather than one’s social position
Delirium Reduction Strategies For The Critically Ill
Delirium, an acute and fluctuating disturbance of consciousness and cognition, is a common manifestation of acute brain dysfunction in critically ill patients. Patients with delirium have longer hospital stays and a lower 6-month survival rate than do patients without delirium. Preliminary research suggests that delirium may be associated with cognitive impairment that persists months to years after discharge.
In a large acute care hospital, the cardiac intensive care staff became interested in mitigating their unit’s high delirium rate of ventilated patients. At baseline, many members of the healthcare team did not believe that delirium could be prevented and the predominant view was that critically ill patients were too ill to mobilize. An extensive literature review suggested that early mobilization was extremely beneficial in delirium reduction. As a result, the goal of this performance improvement project was to reduce the prevalence and severity of delirium through progressive mobilization.
Several barriers to preventing delirium were identified through a root cause analysis. Using improvement measures of operational excellence, a number of countermeasures were established. Several positive outcomes of this project were realized to include the development of an early mobility pathway and a bedside mobility assessment tool.
Next steps include a prospective study of the effect this KPI might have on decreasing duration of ventilation days as well as overall length of hospital stay
Effective Theory Approach to the Spontaneous Breakdown of Lorentz Invariance
We generalize the coset construction of Callan, Coleman, Wess and Zumino to
theories in which the Lorentz group is spontaneously broken down to one of its
subgroups. This allows us to write down the most general low-energy effective
Lagrangian in which Lorentz invariance is non-linearly realized, and to explore
the consequences of broken Lorentz symmetry without having to make any
assumptions about the mechanism that triggers the breaking. We carry out the
construction both in flat space, in which the Lorentz group is a global
spacetime symmetry, and in a generally covariant theory, in which the Lorentz
group can be treated as a local internal symmetry. As an illustration of this
formalism, we construct the most general effective field theory in which the
rotation group remains unbroken, and show that the latter is just the
Einstein-aether theory.Comment: 45 pages, no figures
A New Approach to Determine the Initial Mass Function in the Solar Neighborhood
Oxygen to iron abundance ratios of metal-poor stars provide information on
nucleosynthesis yields from massive stars which end in Type II supernova
explosions. Using a standard model of chemical evolution of the Galaxy we have
reproduced the solar neighborhood abundance data and estimated the oxygen and
iron yields of genuine SN II origin. The estimated yields are compared with the
theoretical yields to derive the relation between the lower and upper mass
limits in each generation of stars and the IMF slope. Independently of this
relation, we furthermore derive the relation between the lower mass limit and
the IMF slope from the stellar mass to light ratio in the solar neighborhood.
These independent relations unambiguously determine the upper mass limit of
and the IMF slope index of 1.3 - 1.6 above 1 M_sun. This
upper mass limit corresponds to the mass beyond which stars end as black holes
without ejecting processed matter into the interstellar medium. We also find
that the IMF slope index below 0.5 M_sun cannot be much shallower than 0.8.Comment: 13 pages LaTex, 4 PostScript figures, to appear in ApJ (July 1,
Vol.483
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