1,396 research outputs found
A Knowledge-Based Approach for PLM Implementation Using Modular Benefits Dependency Networks
Part 10: Maturity Implementation and AdoptionInternational audienceIndustrial companies face significant challenges when they engage in the implementation of Product Lifecycle Management. Research has shown that organizations have difficulties in defining concrete and measurable goals and relating enabling technology to business benefits. Moreover, implementation service providers rely heavily on tacit knowledge when it comes to operational details. This paper proposes a conceptual framework as a methodology for implementation teams. It allows teams to reuse implementation knowledge on a detailed level, related to contribution to benefits and business goals. The methodology is derived from emerging, set-based product and process development methodologies and also from benefit management strategies for information systems. The goal of this methodology is to increase the probability that Product Lifecycle Management implementation contributes to the business benefits of organizations and therefore lower the economic risks. The paper describes the method and the result of two explorative case studies
Theory of Multidimensional Solitons
We review a number of topics germane to higher-dimensional solitons in
Bose-Einstein condensates. For dark solitons, we discuss dark band and planar
solitons; ring dark solitons and spherical shell solitons; solitary waves in
restricted geometries; vortex rings and rarefaction pulses; and multi-component
Bose-Einstein condensates. For bright solitons, we discuss instability,
stability, and metastability; bright soliton engineering, including pulsed atom
lasers; solitons in a thermal bath; soliton-soliton interactions; and bright
ring solitons and quantum vortices. A thorough reference list is included.Comment: review paper, to appear as Chapter 5a in "Emergent Nonlinear
Phenomena in Bose-Einstein Condensates: Theory and Experiment," edited by P.
G. Kevrekidis, D. J. Frantzeskakis, and R. Carretero-Gonzalez
(Springer-Verlag
Comparison of ibuprofen release from minitablets and capsules containing ibuprofen: β-Cyclodextrin complex
NOTICE: this is the author’s version of a work that was accepted for publication in European Journal of Pharmaceutics and Biopharmaceutics. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Eur J Pharm Biopharm. 2011 May;78(1):58-66. Epub 2010 Dec 30.Mixtures containing ibuprofen (IB) complexed with b-cyclodextrin (bCD) obtained by two complexation methods [suspension/solution (with water removed by air stream, spray- and freeze-drying) and kneading technique] were processed into pharmaceutical dosage forms (minitablets and capsules). Powders (IB, bCD and IBbCD) were characterized for moisture content, densities (true and bulk), angle of repose and Carr’s index, X-ray and NMR. From physical mixtures and IBbCD complexes without other excipients were prepared 2.5-mm-diameter minitablets and capsules. Minitablets were characterized for the energy of compaction, tensile strength, friability, density and IB release (at pH 1.0 and 7.2), whereby capsules were characterized for IB release. The results from the release of IB were analyzed using different parameters, namely, the similarity factor (f2), the dissolution efficiency (DE) and the amounts released at a certain time (30, 60 and 180 min) and compared statistically (a = 0.05). The release of IB from the minitablets showed no dependency on the amount of water used in the formation of the complexes. Differences were due to the compaction force used or the presence of a shell for the capsules. The differences observed were mostly due to the characteristics of the particles (dependent on the method considered on the formation of the complexes) and neither to the dosage form nor to the complex of the IB
A breast cancer stem cell niche supported by juxtacrine signalling from monocytes and macrophages
The cell-biological program termed the epithelial-mesenchymal transition (EMT) confers on cancer cells mesenchymal traits and an ability to enter the cancer stem cell (CSC) state. However, the interactions between CSCs and their surrounding microenvironment are poorly understood. Here we show that tumour-associated monocytes and macrophages (TAMs) create a CSC niche through juxtacrine signalling with CSCs. We performed quantitative proteomic profiling and found that the EMT program upregulates the expression of CD90, also known as Thy1, and EphA4, which mediate the physical interactions of CSCs with TAMs by directly binding with their respective counter-receptors on these cells. In response, the EphA4 receptor on the carcinoma cells activates Src and NF-κ B. In turn, NF-κ B in the CSCs induces the secretion of a variety of cytokines that serve to sustain the stem cell state. Indeed, admixed macrophages enhance the CSC activities of carcinoma cells. These findings underscore the significance of TAMs as important components of the CSC niche.National Institutes of Health (U.S.) (Grant R01-CA078461)National Institutes of Health (U.S.) (Grant P01-CA080111)National Institutes of Health (U.S.) (Grant U54-CA163109
Re-visiting the relations: Galactic thin disc age-velocity dispersion relation
The velocity dispersion of stars in the solar neighbourhood thin disc
increases with time after star formation. Nordstrom et al. (2004) is the most
recent observational attempt to constrain the age-velocity dispersion relation.
They fitted the age-velocity dispersion relations of each Galactic cardinal
direction space velocity component, U (towards the Galactic centre), V (in the
direction of Galactic rotation) and W (towards the North Galactic Pole), with
power laws and interpreted these as evidence for continuous heating of the disc
in all directions throughout its lifetime. We re-visit these relations with
their data and use Famaey et al. (2005) to show that structure in the local
velocity distribution function distorts the in-plane (U and V) velocity
distributions away from Gaussian so that a dispersion is not an adequate
parametrization of their functions. The age-sigma(W) relation can however be
constrained because the sample is well phase-mixed vertically. We do not find
any local signature of the stellar warp in the Galactic disc. Vertical disc
heating does not saturate at an early stage. Our new result is that a power law
is not required by the data: disc heating models that saturate after ~ 4.5 Gyr
are equally consistent with observations.Comment: Accepted for publication in MNRAS, 24 pages, 20 figure
Oscillations and interactions of dark and dark-bright solitons in Bose-Einstein condensates
Solitons are among the most distinguishing fundamental excitations in a wide
range of non-linear systems such as water in narrow channels, high speed
optical communication, molecular biology and astrophysics. Stabilized by a
balance between spreading and focusing, solitons are wavepackets, which share
some exceptional generic features like form-stability and particle-like
properties. Ultra-cold quantum gases represent very pure and well-controlled
non-linear systems, therefore offering unique possibilities to study soliton
dynamics. Here we report on the first observation of long-lived dark and
dark-bright solitons with lifetimes of up to several seconds as well as their
dynamics in highly stable optically trapped Rb Bose-Einstein
condensates. In particular, our detailed studies of dark and dark-bright
soliton oscillations reveal the particle-like nature of these collective
excitations for the first time. In addition, we discuss the collision between
these two types of solitary excitations in Bose-Einstein condensates.Comment: 9 pages, 4 figure
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