1,522 research outputs found
Sharing, Giving or Reselling: An Economic Analysis
We consider the non-linear properties \ and boundaries in the three forms of sharing, gift, \ and reselling economy. We decode the economic \ rationality and marketplace mechanisms in today’s \ ever booming sharing/gifting/reselling networks. \ We contribute to the fundamental economics literature \ by decomposing a merchandise into two \ parts: the ownership good and the detached good. \ The ownership good can be utilized or shared \ by the owner. The detached good can either be \ given as a gift or be resold for an income. The \ separation is bounded by considering the estimated \ finite life of the good and a future time stamp \ of detachment. We consider owner’s holding cost, \ various transaction costs, rewards, as well as the \ incentive mechanism from the network. We find \ that there exist various conditions when certain \ ownership form is more preferred to the others. \ Our results also indicate that governmental and \ marketplaces’ incentive policies play an important \ role when consumers make decisions among the \ three economic forms and consequently adjusting \ the total social welfare
Pulvinar-Cortex Interactions in Vision and Attention
The ventro-lateral pulvinar is reciprocally connected with the visual areas of the ventral stream that are important for object recognition. To understand the mechanisms of attentive stimulus processing in this pulvinar-cortex loop, we investigated the interactions between the pulvinar, area V4, and IT cortex in a spatial-attention task. Sensory processing and the influence of attention in the pulvinar appeared to reflect its cortical inputs. However, pulvinar deactivation led to a reduction of attentional effects on firing rates and gamma synchrony in V4, a reduction of sensory-evoked responses and overall gamma coherence within V4, and severe behavioral deficits in the affected portion of the visual field. Conversely, pulvinar deactivation caused an increase in low-frequency cortical oscillations, often associated with inattention or sleep. Thus, cortical interactions with the ventro-lateral pulvinar are necessary for normal attention and sensory processing and for maintaining the cortex in an active state. The pulvinar is often proposed to modulate cortical processing with attention. Zhou et al. find that beyond any role in attention, the pulvinar input to cortex seems necessary to maintain the cortex in an active state.National Institutes of Health (U.S.) (Grant R01 EY017292
Understanding Healthcare Knowledge Diffusion in WeChat
Social media such as We Chat provide new ways of communicating healthcare information and knowledge. Many healthcare institutions leverage We Chat public platform to disseminate healthcare knowledge in the hope of attracting public attention. It is critical for them to build a comprehensive understanding of the factors affecting WeChat users’ willingness to diffuse healthcare knowledge, an issue that has seldom been studied in the literature. This research aims to address this gap. Drawing on prior research on word-of-mouth, we develop a research model by integrating six factors regarding three key elements of healthcare knowledge communications: content (interestingness, usefulness, emotionality and positivity), source (source credibility) and channel (institution-based trust). The research model will be tested through a scenario-based online survey. This research is expected to contribute by (1) integrating factors that determine healthcare knowledge diffusion including the factors about content, source and channel, especially including institution-based trust as an important determinant, (2) examining the diffusion of healthcare knowledge and taking WeChat as the research context, and (3) using survey with subjective measurements to test a more comprehensive model. Potential practical implications are offered for healthcare organizations and practitioners
Investigation of Noncovalent Complexes Between β-Cyclodextrin and Polyamide Acids Containing N-Methylpyrrole and N-Methylimidazole by Electrospray Ionization Mass Spectrometry
Electrospray ionization (ESI) mass spectrometry was utilized to investigate noncovalent complexes between β-cyclodextrin (β-CD) and five novel polyamide acids containing N-methylpyrrole and N-methylimidazole. The 1:1 binding mode was specified by examining the binding stoichiometry from ESI mass spectra. It found that polyamide acids with β-CD have binding affinities in the order: ImImImβCOOH > ImPyImβCOOH > ImPyPyβCOOH > PyPyPyβCOOH > NO2PyPyPyβCOOH. The method gives, simultaneously, the binding constants between β-CD and polyamide acids based on a novel linear equation
Online Retailing Channel Addition: Risk Alleviation or Risk Maker?
The retailing industry traditionally considers the optimal products selection and pricing problem, a complex and challenging one, from marketing and consumer behavior\u27s perspectives. In this study, we take a risk perspective and offer an alternative solution to tackling the problem, echoing the most recent literature that looks at non-risk aspects, such as expected consumer preference, market size and predicted profitability. Adopting a mean-variance framework, our approach explicitly takes into account the interconnectedness of retail products and their impact on risk at the portfolio (retailer) level. Extending the analysis to multiple-channel decisions, our results suggest that the introduction of a new retailing channel (e.g. online shops) can reduce the portfolio risk, whereas a lack of synergy between the new channel and the existing ones may lead to a negative impact on the overall performance. We also provide managerial implications on several conditions when retailers are more economically inclined to introduce more retail channels. Interestingly, our model indicates that larger retailers are less likely to expand their online platform
Deep recurrent spiking neural networks capture both static and dynamic representations of the visual cortex under movie stimuli
In the real world, visual stimuli received by the biological visual system
are predominantly dynamic rather than static. A better understanding of how the
visual cortex represents movie stimuli could provide deeper insight into the
information processing mechanisms of the visual system. Although some progress
has been made in modeling neural responses to natural movies with deep neural
networks, the visual representations of static and dynamic information under
such time-series visual stimuli remain to be further explored. In this work,
considering abundant recurrent connections in the mouse visual system, we
design a recurrent module based on the hierarchy of the mouse cortex and add it
into Deep Spiking Neural Networks, which have been demonstrated to be a more
compelling computational model for the visual cortex. Using Time-Series
Representational Similarity Analysis, we measure the representational
similarity between networks and mouse cortical regions under natural movie
stimuli. Subsequently, we conduct a comparison of the representational
similarity across recurrent/feedforward networks and image/video training
tasks. Trained on the video action recognition task, recurrent SNN achieves the
highest representational similarity and significantly outperforms feedforward
SNN trained on the same task by 15% and the recurrent SNN trained on the image
classification task by 8%. We investigate how static and dynamic
representations of SNNs influence the similarity, as a way to explain the
importance of these two forms of representations in biological neural coding.
Taken together, our work is the first to apply deep recurrent SNNs to model the
mouse visual cortex under movie stimuli and we establish that these networks
are competent to capture both static and dynamic representations and make
contributions to understanding the movie information processing mechanisms of
the visual cortex
High-Frequency, Long-Range Coupling Between Prefrontal and Visual Cortex During Attention
Electrical recordings in humans and monkeys show attentional enhancement of evoked responses and gamma synchrony in ventral stream cortical areas. Does this synchrony result from intrinsic activity in visual cortex or from inputs from other structures? Using paired recordings in the frontal eye field (FEF) and area V4, we found that attention to a stimulus in their joint receptive field leads to enhanced oscillatory coupling between the two areas, particularly at gamma frequencies. This coupling appeared to be initiated by FEF and was time-shifted by about 8 to 13 milliseconds across a range of frequencies. Considering the expected conduction and synaptic delays between the areas, this time-shifted coupling at gamma frequencies may optimize the postsynaptic impact of spikes from one area upon the other, improving cross-area communication with attention.Grant EY017292Grant EY1792
Genome Editing of \u3cem\u3eWnt-1\u3c/em\u3e, a Gene Associated with Segmentation, via CRISPR/Cas9 in the Pine Caterpillar Moth, \u3cem\u3eDendrolimus punctatus\u3c/em\u3e
The pine caterpillar moth, Dendrolimus punctatus, is a devastating forest pest. Genetic manipulation of this insect pest is limited due to the lack of genomic and functional genomic toolsets. Recently, CRISPR/Cas9 technology has been demonstrated to be a promising approach to modify the genome. To investigate gene functions during the embryogenesis, we introduced CRISPR/Cas9 system in D. punctatus to precisely and effectively manipulate gene expressions inmutant embryos. Compared to controls, knocking out of DpWnt-1, a gene well known for its role in the early body planning, led to high embryonic mortality. Among these mutants, 32.9% of the embryos and larvae showed an abnormal development. DpWnt-1 mutants predominantly exhibited abnormal posterior segments. In addition, multiple phenotypes were observed, including the loss of limbs and the head deformation, suggesting that DpWnt-1 signaling pathway is necessary for anterior segmentation and appendage development. Overall, our results demonstrate that CRISPR/Cas9 system is feasible and efficient in inducing mutations at a specific locus in D. punctatus. This study not only lays the foundation for characterizing gene functions in a non-model species, but also facilitates the future development of pest control alternatives for a major defoliator
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