558,754 research outputs found
SimLex-999: Evaluating Semantic Models with (Genuine) Similarity Estimation
We present SimLex-999, a gold standard resource for evaluating distributional
semantic models that improves on existing resources in several important ways.
First, in contrast to gold standards such as WordSim-353 and MEN, it explicitly
quantifies similarity rather than association or relatedness, so that pairs of
entities that are associated but not actually similar [Freud, psychology] have
a low rating. We show that, via this focus on similarity, SimLex-999
incentivizes the development of models with a different, and arguably wider
range of applications than those which reflect conceptual association. Second,
SimLex-999 contains a range of concrete and abstract adjective, noun and verb
pairs, together with an independent rating of concreteness and (free)
association strength for each pair. This diversity enables fine-grained
analyses of the performance of models on concepts of different types, and
consequently greater insight into how architectures can be improved. Further,
unlike existing gold standard evaluations, for which automatic approaches have
reached or surpassed the inter-annotator agreement ceiling, state-of-the-art
models perform well below this ceiling on SimLex-999. There is therefore plenty
of scope for SimLex-999 to quantify future improvements to distributional
semantic models, guiding the development of the next generation of
representation-learning architectures
In vivo PET quantification of the dopamine transporter in rat brain with [ÂčâžF]LBT-999.
INTRODUCTION:
We examined whether [(18)F]LBT-999 ((E)-N-(4-fluorobut-2-enyl)2ÎČ-carbomethoxy-3ÎČ-(4'-tolyl)nortropane) is an efficient positron emission tomography (PET) tracer for the quantification of the dopamine transporter (DAT) in the healthy rat brain.
METHODS:
PET studies were performed using several experimental designs, i.e. test-retest, co-injection with different doses of unlabelled LBT, displacement with GBR12909 and pre-injection of amphetamine.
RESULTS:
The uptake of [(18)F]LBT-999 confirmed its specific binding to the DAT. The non-displaceable uptake (BP(ND)) in the striatum, between 5.37 and 4.39, was highly reproducible and reliable, and was decreased by 90% by acute injection of GBR12909. In the substantia nigra/ventral tegmental area (SN/VTA), the variability was higher and the reliability was lower. Pre-injection of amphetamine induced decrease of [(18)F]LBT-999 BP(ND) of 50% in the striatum.
CONCLUSIONS:
[(18)F]LBT-999 allows the quantification of the DAT in living rat brain with high reproducibility, sensitivity and specificity. It could be used to quantify the DAT in rodent models, thereby allowing to study neurodegenerative and neuropsychiatric diseases
A Good Start: Two-Year Effects of a Freshmen Learning Community Program at Kingsborough Community College
Freshmen in a "learning community" at Kingsborough Community College in Brooklyn, NY, moved more quickly through developmental English requirements, took and passed more courses, and earned more credits in their first semester than students in a control group. Two years later, they were also somewhat more likely to be enrolled in college
When is .999... less than 1?
We examine alternative interpretations of the symbol described as nought,
point, nine recurring. Is "an infinite number of 9s" merely a figure of speech?
How are such alternative interpretations related to infinite cardinalities? How
are they expressed in Lightstone's "semicolon" notation? Is it possible to
choose a canonical alternative interpretation? Should unital evaluation of the
symbol .999 . . . be inculcated in a pre-limit teaching environment? The
problem of the unital evaluation is hereby examined from the pre-R, pre-lim
viewpoint of the student.Comment: 28 page
Resource allocation for massively multiplayer online games using fuzzy linear assignment technique
This paper investigates the possible use of fuzzy system and Linear Assignment Problem (LAP) for resource allocation for Massively Multiplayer Online Games (MMOGs). Due to the limitation of design capacity of such complex MMOGs, resources available in the game cannot be unlimited. Resources in this context refer to items used to support the game play and activities in the MMOGs, also known as in-game resources. As for network resources, it is also one of the important research areas for MMOGs due to the increasing number of players. One of the main objectives is to ensure the Quality of Service (QoS) in the MMOGs environment for each player. Regardless, which context the resource is defined, the proposed method can still be used. Simulated results based on the network resources to ensure QoS shows that the proposed method could be an alternative
ASCA view on High-Redshift Radio-Quiet Quasars
We briefly discuss the latest ASCA results on the X-ray spectral properties
of high-redshift radio-quiet quasars.Comment: 4 pages, 1 figure, to appear in the Proceedings of the Conference
"X-ray Astronomy '999: Stellar Endpoints, AGNs, and the Diffuse X-ray
Background (September 6-10 - 1999
Design and evaluation of dry-coated tablets for colonic delivery of diclofenac sodium
A colonic drug delivery system is required to protect a drug during its transit through the upper gastro-intestinal tract and allow its release in the colon. The aim of this study was the preparation of dry-coated tablets designed for colonic release of the model drug Diclofenac sodium (DS). The system consists of a drug-pectine (PC) mixture as the core and hydroxypropylmethylcellulose (HPMC) alone or mixed in different ratios with poly(Δ-caprolactone) (CL) as the coat layer
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