381 research outputs found
Least Generalizations and Greatest Specializations of Sets of Clauses
The main operations in Inductive Logic Programming (ILP) are generalization
and specialization, which only make sense in a generality order. In ILP, the
three most important generality orders are subsumption, implication and
implication relative to background knowledge. The two languages used most often
are languages of clauses and languages of only Horn clauses. This gives a total
of six different ordered languages. In this paper, we give a systematic
treatment of the existence or non-existence of least generalizations and
greatest specializations of finite sets of clauses in each of these six ordered
sets. We survey results already obtained by others and also contribute some
answers of our own. Our main new results are, firstly, the existence of a
computable least generalization under implication of every finite set of
clauses containing at least one non-tautologous function-free clause (among
other, not necessarily function-free clauses). Secondly, we show that such a
least generalization need not exist under relative implication, not even if
both the set that is to be generalized and the background knowledge are
function-free. Thirdly, we give a complete discussion of existence and
non-existence of greatest specializations in each of the six ordered languages.Comment: See http://www.jair.org/ for any accompanying file
Canine liver transplantation under nva cyclosporine versus cyclosporine
The immunosuppressive qualities and other features of a new cyclosporine (CsA) analogue, Nva 2-cyclosporine (Nva 2-CsA) were examined using canine orthotopic liver allografts. The mean survival time was 11.8±9.6 (SD) days in dogs without treatment, 60.8±34.4 days with Nva 2-CsA and 65.1±33.0 days with CsA. Functional abnormalities indicating toxic side effects were not noted either with Nva 2-CsA or with CsA. Using the same oral dose, the rate of blood level rise and the amount of the rise were greater with Nva2-CsA. Histopathologically, Nva2-CsA the treatment was associated with the same degree of hydropic vocuolation in the pars recta of the proximal tubules as CsA treatment. Thus, in the dog, Nva2-CsA had identical immunosuppressive properties as CsA, with no functionally detectable toxicity affecting the liver and kidney. © 1986 by The Williams & Wilkins Co
Modified Gravity on the Brane and Dark Energy
We analyze the dynamics of an AdS5 braneworld with matter fields when gravity
is allowed to deviate from the Einstein form on the brane. We consider exact
5-dimensional warped solutions which are associated with conformal bulk fields
of weight -4 and describe on the brane the following three dynamics: those of
inhomogeneous dust, of generalized dark radiation, and of homogeneous
polytropic dark energy. We show that, with modified gravity on the brane, the
existence of such dynamical geometries requires the presence of non-conformal
matter fields confined to the brane.Comment: Revised version published in Gen. Rel. Grav. Typos corrected, updated
reference and some remarks added for clarity. 11 pages, latex, no figure
Erraticity Analysis of Soft Production by ECOMB
Event-to-event fluctuations of the spatial patterns of the final states of
high-enery collisions, referred to as erraticity, are studied for the data
generated by a soft-interaction model called ECOMB. The moments do
not show simple power-law dependences on the bin size. New measures of
erraticity are proposed that generalizes the bin-size dependence. The method
should be applied not only to the soft production data of NA22 and NA27 to
check the dynamical content of ECOMB, but also to other collision processes,
such as annihilation and heavy-ion collisions.Comment: 8 pages (Latex) + 7 figures (ps file), submitted to Phys. Rev.
Self-Similarity of the Negative Binomial Multiplicity Distributions
The negative binomial distribution is self similar: If the spectrum over the
whole rapidity range gives rise to a negative binomial, in absence of
correlation and if the source is unique, also a partial range in rapidity gives
rise to the same distribution. The property is not seen in experimental data,
which are rather consistent with the presence of a number of independent
sources. When multiplicities are very large self similarity might be used to
isolate individual sources is a complex production process.Comment: 10 pages, plane tex, no figure
Brane World Dynamics and Conformal Bulk Fields
In the Randall-Sundrum scenario we investigate the dynamics of a spherically
symmetric 3-brane world when matter fields are present in the bulk. To analyze
the 5-dimensional Einstein equations we employ a global conformal
transformation whose factor characterizes the symmetric warp. We find a
new set of exact dynamical collapse solutions which localize gravity in the
vicinity of the brane for a stress-energy tensor of conformal weight -4 and a
warp factor that depends only on the coordinate of the fifth dimension.
Geometries which describe the dynamics of inhomogeneous dust and generalized
dark radiation on the brane are shown to belong to this set. The conditions for
singular or globally regular behavior and the static marginally bound limits
are discussed for these examples. Also explicitly demonstrated is complete
consistency with the effective point of view of a 4-dimensional observer who is
confined to the brane and makes the same assumptions about the bulk degrees of
freedom.Comment: 26 pages, latex, no figures. Minor revisions. Some references added.
Revised version to appear in Phys. Rev.
Feasibility and acceptance of electronic monitoring of symptoms and syndromes using a handheld computer in patients with advanced cancer in daily oncology practice
Purpose: We investigated the feasibility and acceptance of electronic monitoring of symptoms and syndromes in oncological outpatient clinics using a PALM (handheld computer). Methods: The assessment of a combination of symptoms and clinical benefit parameters grouped in four pairs was tested in a pilot phase in advanced cancer patients. Based on these experiences, the software E-MOSAIC was developed, consisting of patient-reported symptoms and nutritional intake and objective assessments (weight, weight loss, performance status and medication for pain, fatigue, and cachexia). E-MOSAIC was then tested in four Swiss oncology centers. In order to compare the methods, patients completed the E-MOSAIC as a paper and a PALM version. Preferences of version and completion times were collected. Assessments were compared using Wilcoxon signed-rank tests , and the test-retest reliability was evaluated. Results: The pilot phase was completed by 22 patients. Most patients and physicians perceived the assessment as useful. Sixty-two patients participated in the feasibility study. Twelve patients reported problems (understanding, optical, tactile), and five patients could not complete the assessment. The median time to complete the PALM-based assessment was 3min. Forty-nine percent of patients preferred the PALM, 23% preferred a paper version, and 28% of patients had no preference. Paper vs. PALM revealed no significant differences in symptoms, but in nutritional intake (p = 0.013). Test-retest (1h, n = 20) reliability was satisfactory (r = 073-98). Conclusion: Electronic symptom and clinical benefit monitoring is feasible in oncology outpatient clinics and perceived as useful by patients, oncology nurses, and oncologists. E-MOSAIC is tested in a prospective randomized trial
Present Status and Future of DCC Analysis
Disoriented Chiral Condensates (DCC) have been predicted to form in high
energy heavy ion collisions where the approximate chiral symmetry of QCD has
been restored. This leads to large imbalances in the production of charged to
neutral pions. Sophisticated analysis methods are being developed to
disentangle DCC events out of the large background of events with
conventionally produced particles. We present a short review of current
analysis methods and future prospects.Comment: 12 pages, 5 figures. Invited talk presented at the 13th International
Conference on Ultrarelativistic Nucleus-Nucleus Collisions (Quark Matter 97),
Tsukuba, Japan, 1-5 Dec 199
Accessible opera : overcoming linguistic and sensorial barriers
The desire to make media available for all has been rapidly accepted and implemented by most European countries. Opera, as one of the many audiovisual representations, also falls under the category of production which needs to be made accessible and this article aims to analyse how opera has gone through a complete transformation to become a cultural event for all, overcoming not only linguistic but also sensorial barriers. The first part of the article analyses the various forms of translation associated with opera and the main challenges they entail. The second presents different systems used to make opera accessible to the sensorially challenged, highlighting their main difficulties. Examples from research carried out at the Barcelona's Liceu opera house are presented to illustrate various modalities, especially audio description. All in all, it is our aim to show how translated-related processes have made it possible to open opera to a wider audience despite some initial reluctance
Weather, disease, and wheat breeding effects on Kansas wheat varietal yields, 1985 to 2011.
Wheat (Triticum aestivum L.) yields in Kansas have increased due to wheat breeding and improved agronomic practices, but are subject to climate and disease challenges. The objective of this research is to quantify the impact of weather, disease, and genetic improvement on wheat yields of varieties grown in 11 locations in Kansas from 1985 to 2011. Wheat variety yield data from Kansas performance tests were matched with comprehensive location-specific disease and weather data, including seasonal precipitation, monthly air temperature, air temperature and solar radiation around anthesis, and vapor pressure deficit (VPD). The results show that wheat breeding programs increased yield by 34 kg ha⁻¹ yr⁻¹. From 1985 through 2011, wheat breeding increased average wheat yields by 917 kg ha⁻¹, or 27% of total yield. Weather was found to have a large impact on wheat yields. Simulations demonstrated that a 1°C increase in projected mean temperature was associated with a decrease in wheat yields of 715 kg ha⁻¹, or 21%. Weather, diseases, and genetics all had significant impacts on wheat yields in 11 locations in Kansas during 1985 to 2011
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