633 research outputs found
Throngs
Ceramic is an important element of my artworks. It is a material with strong bearing capacity, and at the same time, it is a tool with the attribute of nature and social function, for the similarity with humans can be found in it. Thanks to its characteristics, I am able to transform the forms, colors, and quality to complete my works. Collected from nature, carved with human hands, the clay is cultivated and my expectation of the outside world is satisfied
Effect of size, shape, and surface modification on cytotoxicity of gold nanoparticles to human Hep-2 and canine MDCK cells
There have been increasing interests in applying gold nanoparticles in biological research, drug delivery, and therapy. As the interaction of gold nanoparticles with cells relies on properties of nanoparticles, the cytotoxicity is complex and still under debating. In this work, we investigate the cytotoxicity of gold nanoparticles of different encapsulations, surface charge states, sizes and shapes to both human HEp-2 and canine MDCK cells. We found that cetyltrimethylammonium-bromide- (CTAB-) encapsulated gold nanorods (GNRs) were relatively higher cytotoxic than GNRs undergone further polymer coating and citrate stabilized gold nanospheres (GNSs). The toxicity of CTAB-encapsulated GNRs was mainly caused by CTAB on GNRs’ surface but not free CTAB in the solution. No obvious difference was found among GNRs of different aspect ratios. Time-lapse study revealed that cell death caused by GNRs occurred predominately within one hour through apoptosis, whereas cell death by free CTAB was in a time- and dose-dependent manner. Both positively and negatively surface-charged polymer-coated GNRs (PSS-GNRs and PAH-PSS-GNRs) showed similar levels of cytotoxic, suggesting the significance of surface functionality rather than surface charge in this case
Interplay between Social Media and Traditional Media: An Empirical Study in the Motion Picture Industry
Marketers leverage multiple media outlets to promote products. There are three media types: paid (e.g., advertising on TV), owned (e.g., company website), and earned (e.g., consumers’ word-of-mouth) media. The effects of individual media channels and the interrelationships within paid media have been examined by prior literature. However, little is known about interplay across different types of media channels. We investigate how social media marketing (both owned and earned media) and the interplay between traditional paid media and social media affect product sales. We analyze how promotional activities across different media channels influence the box office revenues of 200 movies in their opening weekends and subsequent weeks, respectively. We find empirical evidence that social media marketing is positively associated with product sales, especially in the initial product launch period. Additionally, traditional media and social media are substitutes. We discuss the implications of these results and outline our on-going research plan
Effect of size, shape, and surface modification on cytotoxicity of gold nanoparticles to human Hep-2 and canine MDCK cells
There have been increasing interests in applying gold nanoparticles in biological research, drug delivery, and therapy. As the interaction of gold nanoparticles with cells relies on properties of nanoparticles, the cytotoxicity is complex and still under debating. In this work, we investigate the cytotoxicity of gold nanoparticles of different encapsulations, surface charge states, sizes and shapes to both human HEp-2 and canine MDCK cells. We found that cetyltrimethylammonium-bromide- (CTAB-) encapsulated gold nanorods (GNRs) were relatively higher cytotoxic than GNRs undergone further polymer coating and citrate stabilized gold nanospheres (GNSs). The toxicity of CTAB-encapsulated GNRs was mainly caused by CTAB on GNRs’ surface but not free CTAB in the solution. No obvious difference was found among GNRs of different aspect ratios. Time-lapse study revealed that cell death caused by GNRs occurred predominately within one hour through apoptosis, whereas cell death by free CTAB was in a time- and dose-dependent manner. Both positively and negatively surface-charged polymer-coated GNRs (PSS-GNRs and PAH-PSS-GNRs) showed similar levels of cytotoxic, suggesting the significance of surface functionality rather than surface charge in this case
Effect of size, shape, and surface modification on cytotoxicity of gold nanoparticles to human Hep-2 and canine MDCK cells
There have been increasing interests in applying gold nanoparticles in biological research, drug delivery, and therapy. As the interaction of gold nanoparticles with cells relies on properties of nanoparticles, the cytotoxicity is complex and still under debating. In this work, we investigate the cytotoxicity of gold nanoparticles of different encapsulations, surface charge states, sizes and shapes to both human HEp-2 and canine MDCK cells. We found that cetyltrimethylammonium-bromide- (CTAB-) encapsulated gold nanorods (GNRs) were relatively higher cytotoxic than GNRs undergone further polymer coating and citrate stabilized gold nanospheres (GNSs). The toxicity of CTAB-encapsulated GNRs was mainly caused by CTAB on GNRs’ surface but not free CTAB in the solution. No obvious difference was found among GNRs of different aspect ratios. Time-lapse study revealed that cell death caused by GNRs occurred predominately within one hour through apoptosis, whereas cell death by free CTAB was in a time- and dose-dependent manner. Both positively and negatively surface-charged polymer-coated GNRs (PSS-GNRs and PAH-PSS-GNRs) showed similar levels of cytotoxic, suggesting the significance of surface functionality rather than surface charge in this case
Tunable interlayer delocalization of excitons in layered organic-inorganic halide perovskites
Layered organic-inorganic halide perovskites exhibit remarkable structural and chemical diversity and hold great promise for optoelectronic devices. In these materials, excitons are thought to be strongly confined within the inorganic metal halide layers with interlayer coupling generally suppressed by the organic cations. Here, we present an in-depth study of the energy and spatial distribution of the lowest-energy excitons in layered organic-inorganic halide perovskites from first-principles many-body perturbation theory, within the GW approximation and the Bethe-Salpeter equation. We find that the quasiparticle band structures, linear absorption spectra, and exciton binding energies depend strongly on the distance and the alignment of adjacent metal halide perovskite layers. Furthermore, we show that exciton delocalization can be modulated by tuning the interlayer distance and alignment, both parameters determined by the chemical composition and size of the organic cations. Our calculations establish the general intuition needed to engineer excitonic properties in novel halide perovskite nanostructures
Low-resource Personal Attribute Prediction from Conversation
Personal knowledge bases (PKBs) are crucial for a broad range of applications
such as personalized recommendation and Web-based chatbots. A critical
challenge to build PKBs is extracting personal attribute knowledge from users'
conversation data. Given some users of a conversational system, a personal
attribute and these users' utterances, our goal is to predict the ranking of
the given personal attribute values for each user. Previous studies often rely
on a relative number of resources such as labeled utterances and external data,
yet the attribute knowledge embedded in unlabeled utterances is underutilized
and their performance of predicting some difficult personal attributes is still
unsatisfactory. In addition, it is found that some text classification methods
could be employed to resolve this task directly. However, they also perform not
well over those difficult personal attributes. In this paper, we propose a
novel framework PEARL to predict personal attributes from conversations by
leveraging the abundant personal attribute knowledge from utterances under a
low-resource setting in which no labeled utterances or external data are
utilized. PEARL combines the biterm semantic information with the word
co-occurrence information seamlessly via employing the updated prior attribute
knowledge to refine the biterm topic model's Gibbs sampling process in an
iterative manner. The extensive experimental results show that PEARL
outperforms all the baseline methods not only on the task of personal attribute
prediction from conversations over two data sets, but also on the more general
weakly supervised text classification task over one data set.Comment: Accepted by AAAI'2
Personal Attribute Prediction from Conversations
Personal knowledge bases (PKBs) are critical to many applications, such as
Web-based chatbots and personalized recommendation. Conversations containing
rich personal knowledge can be regarded as a main source to populate the PKB.
Given a user, a user attribute, and user utterances from a conversational
system, we aim to predict the personal attribute value for the user, which is
helpful for the enrichment of PKBs. However, there are three issues existing in
previous studies: (1) manually labeled utterances are required for model
training; (2) personal attribute knowledge embedded in both utterances and
external resources is underutilized; (3) the performance on predicting some
difficult personal attributes is unsatisfactory. In this paper, we propose a
framework DSCGN based on the pre-trained language model with a noise-robust
loss function to predict personal attributes from conversations without
requiring any labeled utterances. We yield two categories of supervision, i.e.,
document-level supervision via a distant supervision strategy and
contextualized word-level supervision via a label guessing method, by mining
the personal attribute knowledge embedded in both unlabeled utterances and
external resources to fine-tune the language model. Extensive experiments over
two real-world data sets (i.e., a profession data set and a hobby data set)
show our framework obtains the best performance compared with all the twelve
baselines in terms of nDCG and MRR.Comment: Accepted by WWW'22 Companio
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