8,908 research outputs found
Recommended from our members
Adding chopped straw to concentrate feed: the effect of inclusion rate and particle length on intake behaviour of horses
At Face Value: Visual Antecedents of Impression Formation in Servicescapes
Consumers may base employee impressions on physical appearance\ud
and displayed personal objects. In a scenario experiment,\ud
using photos of a physician and a 360-degree panorama of his\ud
consultation room, we examined the effects of appearance and\ud
tangibles on impression formation. Study 1 shows that observers\ud
employ various strategies of combining information from different\ud
sources when forming an impression of the employeeâs friendliness\ud
and competence. Whereas previous research has shown that impression\ud
formation based on personal appearances proceeds in an\ud
automatic fashion, the findings of study 2 indicate that impression\ud
formation grounded in the perception of tangibles requires more\ud
elaborate processin
Measurement of Permanent Electric Dipole Moments of Charged Hadrons in Storage Rings
Permanent Electric Dipole Moments (EDMs) of elementary particles violate two
fundamental symmetries: time reversal invariance (T) and parity (P). Assuming
the CPT theorem this implies CP-violation. The CP-violation of the Standard
Model is orders of magnitude too small to be observed experimentally in EDMs in
the foreseeable future. It is also way too small to explain the asymmetry in
abundance of matter and anti-matter in our universe. Hence, other mechanisms of
CP violation outside the realm of the Standard Model are searched for and could
result in measurable EDMs.
Up to now most of the EDM measurements were done with neutral particles. With
new techniques it is now possible to perform dedicated EDM experiments with
charged hadrons at storage rings where polarized particles are exposed to an
electric field. If an EDM exists the spin vector will experience a torque
resulting in change of the original spin direction which can be determined with
the help of a polarimeter. Although the principle of the measurement is simple,
the smallness of the expected effect makes this a challenging experiment
requiring new developments in various experimental areas.
Complementary efforts to measure EDMs of proton, deuteron and light nuclei
are pursued at Brookhaven National Laboratory and at Forschungszentrum Juelich
with an ultimate goal to reach a sensitivity of 10^{-29} e cm.Comment: 8 pages, 2 figure
Truthful Mechanisms for Matching and Clustering in an Ordinal World
We study truthful mechanisms for matching and related problems in a partial
information setting, where the agents' true utilities are hidden, and the
algorithm only has access to ordinal preference information. Our model is
motivated by the fact that in many settings, agents cannot express the
numerical values of their utility for different outcomes, but are still able to
rank the outcomes in their order of preference. Specifically, we study problems
where the ground truth exists in the form of a weighted graph of agent
utilities, but the algorithm can only elicit the agents' private information in
the form of a preference ordering for each agent induced by the underlying
weights. Against this backdrop, we design truthful algorithms to approximate
the true optimum solution with respect to the hidden weights. Our techniques
yield universally truthful algorithms for a number of graph problems: a
1.76-approximation algorithm for Max-Weight Matching, 2-approximation algorithm
for Max k-matching, a 6-approximation algorithm for Densest k-subgraph, and a
2-approximation algorithm for Max Traveling Salesman as long as the hidden
weights constitute a metric. We also provide improved approximation algorithms
for such problems when the agents are not able to lie about their preferences.
Our results are the first non-trivial truthful approximation algorithms for
these problems, and indicate that in many situations, we can design robust
algorithms even when the agents may lie and only provide ordinal information
instead of precise utilities.Comment: To appear in the Proceedings of WINE 201
Field trial with oral vaccination of dogs against rabies in the Philippines
BACKGROUND: The potential role of oral vaccination of dogs against rabies in the Philippines was investigated in terms of safety and efficacy. METHODS: Prior to the vaccination campaign, a house-to-house survey was carried out to collect data on the dog population in the study area, the coastal village of Mindoro. During the vaccination campaign all households were visited again, and all dogs encountered (>2 months old) were, if possible, vaccinated. Furthermore, 14 dogs vaccinated were bled on different occasions. RESULTS: During the survey, a total of 216 dogs were counted, and none of these animals had previously been vaccinated against rabies. Only 17 dogs could be restrained and subsequently vaccinated directly by the vaccinators. Another 126 dogs were offered a local-made boiled intestine bait, containing a capsule filled with 3.0 ml SAD B19 (10(7.9) FFU/ml). The bait acceptance rate of dogs offered a bait was 96.1%. The vaccination coverage of the dog population (> 2 months old) estimated by the number of animals vaccinated directly and the number of dogs that accepted a bait and subsequently punctured the vaccine container was 76%. Fifteen and 29 days after the vaccination campaign 6 and 10 dogs (n = 14) had rabies virus neutralizing antibody titres of â„ 0.5 IU/ml, respectively. No unintentional contacts of nontarget species, including humans, with the vaccine virus were reported. CONCLUSIONS: The results of the campaign show that oral vaccination of dogs against rabies is a promising supplementary method in dog rabies control in the Philippines
MR Imaging Texture Analysis in the Abdomen and Pelvis
Texture analysis (TA) is a form of radiomics and refers to quantitative measurements of the
histogram, distribution and/or relationship of pixel intensities or gray scales within a region of
interest on an image. TA can be applied to MRI of the abdomen and pelvis, with the main
strength being quantitative analysis of pixel intensities and heterogeneity rather than
subjective/qualitative analysis. There are multiple limitations of MR texture analysis (MRTA)
including a dependency on image acquisition and reconstruction parameters, non-standardized
approaches without or with image filtration, diverse software methods and applications, and
statistical challenges relating numerous texture analysis results to clinical outcomes in
retrospective pilot studies with small sample sizes. Despite these limitations, there is a growing
body of literature supporting MRTA. In this review, the application of MRTA to the abdomen
and pelvis will be discussed, including tissue or tumor characterization and response evaluation
or prediction of outcomes in various tumors
Appearances can be deceiving:The portayal of weight and embodied meaning portrayal in product design
Steps in the bacterial flagellar motor
The bacterial flagellar motor is a highly efficient rotary machine used by
many bacteria to propel themselves. It has recently been shown that at low
speeds its rotation proceeds in steps [Sowa et al. (2005) Nature 437,
916--919]. Here we propose a simple physical model that accounts for this
stepping behavior as a random walk in a tilted corrugated potential that
combines torque and contact forces. We argue that the absolute angular position
of the rotor is crucial for understanding step properties, and show this
hypothesis to be consistent with the available data, in particular the
observation that backward steps are smaller on average than forward steps. Our
model also predicts a sublinear torque-speed relationship at low torque, and a
peak in rotor diffusion as a function of torque
- âŠ