618 research outputs found
Agents’ interaction in virtual storytelling
In this paper we describe a fully implemented prototype for interactive storytelling using the Unreal engine. Using a sit-com like scenario as an example of how the dynamic interactions between agents and/or the user dramatise the emerging story. Hierarchical Task Networks (HTNs) are formalised using AND/OR graphs, which are used to describe the many possible variations of the story at a sub-goal level, and the set of all behaviours (from a narrative perspective) of the primary actors at a terminal action level. We introduc
Belief Revision in Structured Probabilistic Argumentation
In real-world applications, knowledge bases consisting of all the information
at hand for a specific domain, along with the current state of affairs, are
bound to contain contradictory data coming from different sources, as well as
data with varying degrees of uncertainty attached. Likewise, an important
aspect of the effort associated with maintaining knowledge bases is deciding
what information is no longer useful; pieces of information (such as
intelligence reports) may be outdated, may come from sources that have recently
been discovered to be of low quality, or abundant evidence may be available
that contradicts them. In this paper, we propose a probabilistic structured
argumentation framework that arises from the extension of Presumptive
Defeasible Logic Programming (PreDeLP) with probabilistic models, and argue
that this formalism is capable of addressing the basic issues of handling
contradictory and uncertain data. Then, to address the last issue, we focus on
the study of non-prioritized belief revision operations over probabilistic
PreDeLP programs. We propose a set of rationality postulates -- based on
well-known ones developed for classical knowledge bases -- that characterize
how such operations should behave, and study a class of operators along with
theoretical relationships with the proposed postulates, including a
representation theorem stating the equivalence between this class and the class
of operators characterized by the postulates
Chemotherapy following radium-223 dichloride treatment in ALSYMPCA
BACKGROUND
Radium-223 prolongs overall survival in patients with castration-resistant prostate cancer (CRPC) and symptomatic bone metastases, regardless of prior docetaxel. Whether or not chemotherapy can be safely administered following radium-223 treatment is of clinical importance. An exploratory analysis of prospectively collected data, from the ALSYMPCA (ALpharadin in SYMptomatic Prostate CAncer) patient subgroup who received chemotherapy after radium-223 or placebo treatment, was conducted to evaluate the safety and efficacy of chemotherapy following radium-223.
METHODS
In ALSYMPCA, CRPC patients with symptomatic bone metastases and no visceral metastases were randomized 2:1 to receive six injections of radium-223 (50 kBq/kg IV) or placebo plus best standard of care, stratified by prior docetaxel, baseline alkaline phosphatase, and current bisphosphonate use. In this exploratory analysis, chemotherapy agents administered following study treatment were identified; timing and duration were calculated. Hematologic safety was reviewed, and overall survival analyzed.
RESULTS
Overall, 142 radium-223 and 64 placebo patients received subsequent chemotherapy; most common were docetaxel (70% radium-223, 72% placebo) and mitoxantrone (16% radium-223, 20% placebo). The majority of patients (61% radium-223, 58% placebo) had received prior docetaxel. Radium-223 patients started subsequent chemotherapy later than placebo patients; chemotherapy duration was similar between groups. In radium-223 and placebo patients receiving subsequent chemotherapy, median hematologic values (hemoglobin, neutrophils, and platelets) remained nearly constant up to 18 months following start of chemotherapy, regardless of prior docetaxel treatment. A low percentage of patients in both groups had grades 3–4 hematologic values (<10%). Platelet count decline, from last measurement before chemotherapy, was numerically greater in radium-223 versus placebo patients. Median overall survivals from start of chemotherapy were 16.0 and 15.8 months following radium-223 and placebo, respectively.
CONCLUSIONS
Chemotherapy following radium-223, regardless of prior docetaxel, is feasible and appears to be well tolerated in patients with CRPC and symptomatic bone metastases
Efficacy and Safety of Radium-223 Dichloride in Symptomatic Castration-resistant Prostate Cancer Patients With or Without Baseline Opioid Use From the Phase 3 ALSYMPCA Trial
Background: The phase 3 ALSYMPCA trial enrolled metastatic castration-resistant prostate
cancer patients with or without baseline opioid use.
Objective: To assess the efficacy and safety of radium-223 dichloride (radium-223) versus
placebo in ALSYMPCA patients by baseline opioid use.
Design, setting, and participants: Nine hundred and twenty one patients enrolled at 136 centers
globally.
Intervention: Radium-223 (50 kBq/kg, intravenous injection) every 4 wk for six cycles or
matching placebo, each plus best standard of care.
Outcome measurements and statistical analysis: Primary endpoint (overall survival [OS]),
main secondary efficacy endpoints, and safety were evaluated by baseline opioid use.
Additional analyses included time to first opioid use, time to first external beam radiation
therapy for bone pain, and safety of concomitant external beam radiation therapy.
Results and limitations: At baseline, 408 (44%) patients had no pain and no analgesic use or
mild pain with nonopioid therapy (World Health Organization ladder pain score 0–1 [nonopioid
subgroup]), and 513 (56%) had moderate pain with occasional opioids or severe pain
with regular daily opioids (World Health Organization ladder pain score 2–3 [opioid subgroup]).
Radium-223 significantly prolonged OS versus placebo in nonopioid (hazard ratio
[HR] = 0.70; 95% confidence interval [CI]: 0.52–0.93; p = 0.013) and opioid (HR = 0.68; 95% CI:
0.54–0.86; p = 0.001) subgroups, and significantly reduced risk of symptomatic skeletal events
versus placebo, regardless of baseline opioid use (nonopioid subgroup: HR = 0.56, 95% CI: 0.39–
0.82, p = 0.002; opioid subgroup: HR = 0.72, 95% CI: 0.53–0.98, p = 0.038). Time to first opioid
use for bone pain was significantly delayed with radium-223 versus placebo (HR = 0.62, 95% CI:
0.46–0.85, p = 0.002). Adverse event incidences were similar between opioid subgroups.
Conclusions: Radium-223 versus placebo significantly prolonged OS and reduced symptomatic
skeletal event risk with a favorable safety profile in castration-resistant prostate cancer
patients with symptomatic bone metastases, regardless of baseline opioid use.
Patient summary: In this ALSYMPCA opioid subgroup analysis, baseline symptom levels did
not appear to impact radium-223 dichloride efficacy or safet
Search for More Declarativity
Good tree search algorithms are a key requirement for inference
engines of rule languages. As Prolog exemplifies, inference engines
based on traditional uninformed search methods with their well-known
deficiencies are prone to compromise declarativity, the primary concern
of rule languages. The paper presents a new family of uninformed search
algorithms that combine the advantages of the traditional ones while
avoiding their shortcomings. Moreover, the paper introduces a formal
framework based on partial orderings, which allows precise and elegant
analysis of such algorithms
Dimension-specific search for multimedia retrieval.
Observing that current Global Similarity Measures (GSM) which average the effect of few significant differences on all dimensions may cause possible performance limitation, we propose the first Dimension-specific Similarity Measure (DSM) to take local dimensionspecific constraints into consideration. The rationale for DSM is that significant differences on some individual dimensions may lead to different semantics. An efficient search algorithm is proposed to achieve fast Dimension-specific KNN (DKNN) retrieval. Experiment results show that our methods outperform traditional methods by large gaps
Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS
The chi_b(nP) quarkonium states are produced in proton-proton collisions at
the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS
detector. Using a data sample corresponding to an integrated luminosity of 4.4
fb^-1, these states are reconstructed through their radiative decays to
Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks
corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new
structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is
also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes.
This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table,
corrected author list, matches final version in Physical Review Letter
Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS
We present the results of a search for new, heavy particles that decay at a
significant distance from their production point into a final state containing
charged hadrons in association with a high-momentum muon. The search is
conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV
and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS
detector operating at the Large Hadron Collider. Production of such particles
is expected in various scenarios of physics beyond the standard model. We
observe no signal and place limits on the production cross-section of
supersymmetric particles in an R-parity-violating scenario as a function of the
neutralino lifetime. Limits are presented for different squark and neutralino
masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final
version to appear in Physics Letters
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