55 research outputs found
Sequential Deliberation for Social Choice
In large scale collective decision making, social choice is a normative study
of how one ought to design a protocol for reaching consensus. However, in
instances where the underlying decision space is too large or complex for
ordinal voting, standard voting methods of social choice may be impractical.
How then can we design a mechanism - preferably decentralized, simple,
scalable, and not requiring any special knowledge of the decision space - to
reach consensus? We propose sequential deliberation as a natural solution to
this problem. In this iterative method, successive pairs of agents bargain over
the decision space using the previous decision as a disagreement alternative.
We describe the general method and analyze the quality of its outcome when the
space of preferences define a median graph. We show that sequential
deliberation finds a 1.208- approximation to the optimal social cost on such
graphs, coming very close to this value with only a small constant number of
agents sampled from the population. We also show lower bounds on simpler
classes of mechanisms to justify our design choices. We further show that
sequential deliberation is ex-post Pareto efficient and has truthful reporting
as an equilibrium of the induced extensive form game. We finally show that for
general metric spaces, the second moment of of the distribution of social cost
of the outcomes produced by sequential deliberation is also bounded
Nickel pyrithione induces apoptosis in chronic myeloid leukemia cells resistant to imatinib via both Bcr/Abl-dependent and Bcr/Abl-independent mechanisms
Development of an In-Line Near-Infrared Method for Blend Content Uniformity Assessment in a Tablet Feed Frame
Rationalisation of Profiles of Abstract Argumentation Frameworks
Different agents may have different points of view. This can be modelled using different abstract argumentation frameworks, each consisting of a set of arguments and a binary attack-relation between them. A question arising in this context is whether the diversity of views observed in such a profile of argumentation frameworks is consistent with the assumption that every individual argumentation framework is induced by a combination of, first, some basic factual attack-relation between the arguments and, second, the personal preferences of the agent concerned. We treat this question of rationalisability of a profile as an algorithmic problem and identify tractable and intractable cases. This is useful for understanding what types of profiles can reasonably be expected to come up in a multiagent system
Method Development and Validation of an Inline Process Analytical Technology Method for Blend Monitoring in the Tablet Feed Frame Using Raman Spectroscopy
Inline process analytical
technology sensors are the key elements
to enable continuous manufacturing. They facilitate real-time monitoring
of critical quality attributes of both intermediate materials and
finished products. The aim of this study was to demonstrate method
development and validation for inline and offline calibration strategies
to determine the blend content during tablet compression via Raman
spectroscopy. An inline principal component regression model was developed
from Raman spectra collected in the feed frame. At the same time,
an offline study was conducted over a small amount of the calibration
blends using an in-house moving powder setup to simulate the environment
of the feed frame. The model developed offline was able to predict
the active ingredient content after a bias correction and used only
a fraction of the material. The offline method can serve as a simple
method to facilitate calibration development when the time and access
to the press is limited. The study takes into consideration, the necessary
components of method development and offers perspectives on the validation
of an inline process analytics method. Method testing and validation
was performed for the inline process analytical technology method.
The established Raman method was demonstrated as suitable for the
determination of bulk assay of the active ingredient in powders inside
the feed frame for use during batch and continuous manufacturing processes
Fabric Softener–Cellulose Nanocrystal Interaction: A Model for Assessing Surfactant Deposition on Cotton
There
is currently
a renewed interest for improving household and personal-care formulations
to provide more environment-friendly products. Fabric conditioners
used as softeners have to fulfill a number of stability and biodegradability
requirements. They should also display significant adsorption on cotton
under the conditions of use. The quantification of surfactant adsorption
remains however difficult because the fabric-woven structure is complex
and deposited amounts are generally small. Here, we propose a method
to evaluate cellulose–surfactant interactions with increased
detection sensitivity. The method is based on the use of cellulose
nanocrystals (CNCs) in lieu of micron-sized fibers or yarns, combined
with different techniques, including light scattering, optical and
electron microscopy, and electrophoretic mobility. CNCs are rod-shaped
nanoparticles in the form of 200 nm laths that are negatively charged
and can be dispersed in bulk solutions. In this work, we use a double-tailed
cationic surfactant present in fabric softener. Results show that
the surfactants self-assemble into unilamellar, multivesicular, and
multilamellar vesicles, and the interaction with CNCs is driven by
electrostatics. Mutual interactions are strong and lead to the formation
of large-scale aggregates, where the vesicles remain intact at the
cellulose surface. The technique developed here could be exploited
to rapidly assess the fabric conditioner efficiency obtained by varying
the nature and content of their chemical additives
Fabric Softener–Cellulose Nanocrystal Interaction: A Model for Assessing Surfactant Deposition on Cotton
There
is currently
a renewed interest for improving household and personal-care formulations
to provide more environment-friendly products. Fabric conditioners
used as softeners have to fulfill a number of stability and biodegradability
requirements. They should also display significant adsorption on cotton
under the conditions of use. The quantification of surfactant adsorption
remains however difficult because the fabric-woven structure is complex
and deposited amounts are generally small. Here, we propose a method
to evaluate cellulose–surfactant interactions with increased
detection sensitivity. The method is based on the use of cellulose
nanocrystals (CNCs) in lieu of micron-sized fibers or yarns, combined
with different techniques, including light scattering, optical and
electron microscopy, and electrophoretic mobility. CNCs are rod-shaped
nanoparticles in the form of 200 nm laths that are negatively charged
and can be dispersed in bulk solutions. In this work, we use a double-tailed
cationic surfactant present in fabric softener. Results show that
the surfactants self-assemble into unilamellar, multivesicular, and
multilamellar vesicles, and the interaction with CNCs is driven by
electrostatics. Mutual interactions are strong and lead to the formation
of large-scale aggregates, where the vesicles remain intact at the
cellulose surface. The technique developed here could be exploited
to rapidly assess the fabric conditioner efficiency obtained by varying
the nature and content of their chemical additives
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