An OWA-TOPSIS method for multiple criteria decision analysis

A hybrid approach integrating OWA (Ordered Weighted Averaging) aggregation into TOPSIS (technique for order performance by similarity to ideal solution) is proposed to tackle multiple criteria decision analysis (MCDA) problems. First, the setting of extreme points (ideal and anti-ideal points) in TOPSIS is redefined and extended for handling the multiple extreme points situation where a decision maker (DM) or multiple DMs can provide more than one pair of extreme points. Next, three different aggregation schemes are designed to integrate OWA into the TOPSIS analysis procedure. A numerical example is provided to demonstrate the proposed approach and the results are compared for different aggregation settings and confirm the robustness of rankings from different scenarios

Olfactory learning alters navigation strategies and behavioral variability in C. elegans

Animals adjust their behavioral response to sensory input adaptively depending on past experiences. The flexible brain computation is crucial for survival and is of great interest in neuroscience. The nematode C. elegans modulates its navigation behavior depending on the association of odor butanone with food (appetitive training) or starvation (aversive training), and will then climb up the butanone gradient or ignore it, respectively. However, the exact change in navigation strategy in response to learning is still unknown. Here we study the learned odor navigation in worms by combining precise experimental measurement and a novel descriptive model of navigation. Our model consists of two known navigation strategies in worms: biased random walk and weathervaning. We infer weights on these strategies by applying the model to worm navigation trajectories and the exact odor concentration it experiences. Compared to naive worms, appetitive trained worms up-regulate the biased random walk strategy, and aversive trained worms down-regulate the weathervaning strategy. The statistical model provides prediction with $>90 \%$ accuracy of the past training condition given navigation data, which outperforms the classical chemotaxis metric. We find that the behavioral variability is altered by learning, such that worms are less variable after training compared to naive ones. The model further predicts the learning-dependent response and variability under optogenetic perturbation of the olfactory neuron AWC$^\mathrm{ON}$. Lastly, we investigate neural circuits downstream from AWC$^\mathrm{ON}$ that are differentially recruited for learned odor-guided navigation. Together, we provide a new paradigm to quantify flexible navigation algorithms and pinpoint the underlying neural substrates

A DEA-TOPSIS method for multiple criteria decision analysis in emergency management

A hybrid approach of DEA (data envelopment analysis) and TOPSIS (technique for order performance (preference) by similarity to ideal solution) is proposed for multiple criteria decision analysis in emergency management. Two DEA-based optimization models are constructed to facilitate identifying parameter information regarding criterion weights and quantifying qualitative criteria in TOPSIS. An emergency management case study utilizing data from the Emergency Management Australia (EMA) Disasters Database is provided to demonstrate the feasibility of the proposed analysis procedure

Interpersonal prosodic correlation in frontotemporal dementia.

Communication accommodation describes how individuals adjust their communicative style to that of their conversational partner. We predicted that interpersonal prosodic correlation related to pitch and timing would be decreased in behavioral variant frontotemporal dementia (bvFTD). We predicted that the interpersonal correlation in a timing measure and a pitch measure would be increased in right temporal FTD (rtFTD) due to sparing of the neural substrate for speech timing and pitch modulation but loss of social semantics. We found no significant effects in bvFTD, but conversations including rtFTD demonstrated higher interpersonal correlations in speech rate than healthy controls

Long-Term In Vivo Gene Expression via Delivery of PEI–DNA Condensates from Porous Polymer Scaffolds

Nonviral delivery vectors are attractive for gene therapy approaches in tissue engineering, but suffer from low transfection efficiency and short-term gene expression. We hypothesized that the sustained delivery of poly(ethylenimine) (PEI)-condensed DNA from three-dimensional biodegradable scaffolds that encourage cell infiltration could greatly enhance gene expression. To test this hypothesis, a PEI-condensed plasmid encoding β-galactosidase was incorporated into porous poly(lactide-co-glycolide) (PLG) scaffolds, using a gas foaming process. Four conditions were examined: condensed DNA and uncondensed DNA encapsulated into PLG scaffolds, blank scaffolds, and bolus delivery of condensed DNA in combination with implantation of PLG scaffolds. Implantation of scaffolds incorporating condensed β-galactosidase plasmid into the subcutaneous tissue of rats resulted in a high level of gene expression for the entire 15-week duration of the experiment, as exemplified by extensive positive staining for β-galactosidase gene expression observed on the exterior surface and throughout the cross-sections of the explanted scaffolds. No positive staining could be observed for the control conditions either on the exterior surface or in the cross-section at 8- and 15-week time points. In addition, a high percentage (55–60%) of cells within scaffolds incorporating condensed DNA at 15 weeks demonstrated expression of the DNA, confirming the sustained uptake and expression of the encapsulated plasmid DNA. Quantitative analysis of β-galactosidase gene expression revealed that expression levels in scaffolds incorporating condensed DNA were one order of magnitude higher than those of other conditions at the 2- week time point and nearly two orders of magnitude higher than those of the control conditions at the 8- and 15-week time points. This study demonstrated that the sustained delivery of PEI–condensed plasmid DNA from PLG scaffolds led to an in vivo long-term and high level of gene expression, and this system may find application in areas such as bone tissue engineering.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63281/1/hum.2005.16.609.pd

Correcting motion induced fluorescence artifacts in two-channel neural imaging

Imaging neural activity in a behaving animal presents unique challenges in part because motion from an animal's movement creates artifacts in fluorescence intensity time-series that are difficult to distinguish from neural signals of interest. One approach to mitigating these artifacts is to image two channels; one that captures an activity-dependent fluorophore, such as GCaMP, and another that captures an activity-independent fluorophore such as RFP. Because the activity-independent channel contains the same motion artifacts as the activity-dependent channel, but no neural signals, the two together can be used to remove the artifacts. Existing approaches for this correction, such as taking the ratio of the two channels, do not account for channel independent noise in the measured fluorescence. Moreover, no systematic comparison has been made of existing approaches that use two-channel signals. Here, we present Two-channel Motion Artifact Correction (TMAC), a method which seeks to remove artifacts by specifying a generative model of the fluorescence of the two channels as a function of motion artifact, neural activity, and noise. We further present a novel method for evaluating ground-truth performance of motion correction algorithms by comparing the decodability of behavior from two types of neural recordings; a recording that had both an activity-dependent fluorophore (GCaMP and RFP) and a recording where both fluorophores were activity-independent (GFP and RFP). A successful motion-correction method should decode behavior from the first type of recording, but not the second. We use this metric to systematically compare five methods for removing motion artifacts from fluorescent time traces. We decode locomotion from a GCaMP expressing animal 15x more accurately on average than from control when using TMAC inferred activity and outperform all other methods of motion correction tested.Comment: 11 pages, 3 figure

The Role of Celebrities’ Personality Traits & Endorsement on Consumers’ Online Brand Defending and Purchase Behaviour

Celebrity endorsements are widely adopted as part of the marketing strategies for many brands, given celebrities can engage their fans to patronize the brand and to distribute celebrity-featuring promotion messages online. With the proliferation of the Internet, these fans may also defend their beloved celebrities when they are being attacked. However, whether a consumer’s positive attitude to the endorser would impact their behaviour toward the endorsed brand remains unclear. Qualitatively studying based on a few leading online communities, we explored the impact of attitude towards brand-endorsing celebrities on online consumers’ behaviour (likelihood of brand defending and purchase intention), which would foster the brand’s electronic word-of-mouth (eWOM). We also identified several endorsers’ traits that drive consumers’ attitudes towards brand-endorsing celebrities and the role of exposure frequency of celebrity-featured advertisements on consumers’ attitudes towards the endorsed brand

Attenuating Diabetic Vascular and Neuronal Defects by Targeting P2rx7.

Retinal vascular and neuronal degeneration are established pathological features of diabetic retinopathy. Data suggest that defects in the neuroglial network precede the clinically recognisable vascular lesions in the retina. Therefore, new treatments that target early-onset neurodegeneration would be expected to have great value in preventing the early stages of diabetic retinopathy. Here, we show that the nucleoside reverse transcriptase inhibitor lamivudine (3TC), a newly discovered P2rx7 inhibitor, can attenuate progression of both neuronal and vascular pathology in diabetic retinopathy. We found that the expression of P2rx7 was increased in the murine retina as early as one month following diabetes induction. Compared to non-diabetic controls, diabetic mice treated with 3TC were protected against the formation of acellular capillaries in the retina. This occurred concomitantly with a maintenance in neuroglial function, as shown by improved a- and b-wave amplitude, as well as oscillatory potentials. An improvement in the number of GABAergic amacrine cells and the synaptophysin-positive area was also observed in the inner retina of 3TC-treated diabetic mice. Our data suggest that 3TC has therapeutic potential since it can target both neuronal and vascular defects caused by diabetes