2,652 research outputs found
Beyond Keywords and Relevance: A Personalized Ad Retrieval Framework in E-Commerce Sponsored Search
On most sponsored search platforms, advertisers bid on some keywords for
their advertisements (ads). Given a search request, ad retrieval module
rewrites the query into bidding keywords, and uses these keywords as keys to
select Top N ads through inverted indexes. In this way, an ad will not be
retrieved even if queries are related when the advertiser does not bid on
corresponding keywords. Moreover, most ad retrieval approaches regard rewriting
and ad-selecting as two separated tasks, and focus on boosting relevance
between search queries and ads. Recently, in e-commerce sponsored search more
and more personalized information has been introduced, such as user profiles,
long-time and real-time clicks. Personalized information makes ad retrieval
able to employ more elements (e.g. real-time clicks) as search signals and
retrieval keys, however it makes ad retrieval more difficult to measure ads
retrieved through different signals. To address these problems, we propose a
novel ad retrieval framework beyond keywords and relevance in e-commerce
sponsored search. Firstly, we employ historical ad click data to initialize a
hierarchical network representing signals, keys and ads, in which personalized
information is introduced. Then we train a model on top of the hierarchical
network by learning the weights of edges. Finally we select the best edges
according to the model, boosting RPM/CTR. Experimental results on our
e-commerce platform demonstrate that our ad retrieval framework achieves good
performance
Learning from Physical Human Feedback: An Object-Centric One-Shot Adaptation Method
For robots to be effectively deployed in novel environments and tasks, they
must be able to understand the feedback expressed by humans during
intervention. This can either correct undesirable behavior or indicate
additional preferences. Existing methods either require repeated episodes of
interactions or assume prior known reward features, which is data-inefficient
and can hardly transfer to new tasks. We relax these assumptions by describing
human tasks in terms of object-centric sub-tasks and interpreting physical
interventions in relation to specific objects. Our method, Object Preference
Adaptation (OPA), is composed of two key stages: 1) pre-training a base policy
to produce a wide variety of behaviors, and 2) online-updating according to
human feedback. The key to our fast, yet simple adaptation is that general
interaction dynamics between agents and objects are fixed, and only
object-specific preferences are updated. Our adaptation occurs online, requires
only one human intervention (one-shot), and produces new behaviors never seen
during training. Trained on cheap synthetic data instead of expensive human
demonstrations, our policy correctly adapts to human perturbations on realistic
tasks on a physical 7DOF robot. Videos, code, and supplementary material are
provided.Comment: Accepted to ICRA 202
SIRT3 Protects Rotenone-induced Injury in SH-SY5Y Cells by Promoting Autophagy through the LKB1-AMPK-mTOR Pathway.
SIRT3 is a class III histone deacetylase that modulates energy metabolism, genomic stability and stress resistance. It has been implicated as a potential therapeutic target in a variety of neurodegenerative diseases, including Parkinson's disease (PD). Our previous study demonstrates that SIRT3 had a neuroprotective effect on a rotenone-induced PD cell model, however, the exact mechanism is unknown. In this study, we investigated the underlying mechanism. We established a SIRT3 stable overexpression cell line using lentivirus infection in SH-SY5Y cells. Then, a PD cell model was established using rotenone. Our data demonstrate that overexpression of SIRT3 increased the level of the autophagy markers LC3 II and Beclin 1. After addition of the autophagy inhibitor 3-MA, the protective effect of SIRT3 diminished: the cell viability decreased, while the apoptosis rate increased; α-synuclein accumulation enhanced; ROS production increased; antioxidants levels, including SOD and GSH, decreased; and MMP collapsed. These results reveal that SIRT3 has neuroprotective effects on a PD cell model by up-regulating autophagy. Furthermore, SIRT3 overexpression also promoted LKB1 phosphorylation, followed by activation of AMPK and decreased phosphorylation of mTOR. These results suggest that the LKB1-AMPK-mTOR pathway has a role in induction of autophagy. Together, our findings indicate a novel mechanism by which SIRT3 protects a rotenone-induced PD cell model through the regulation of autophagy, which, in part, is mediated by activation of the LKB1-AMPK-mTOR pathway
Solvent-Free Plasticity and Programmable Mechanical Behaviors of Engineered Proteins
Biopolymeric networks with plasticity show great competences in diverse fields owing to the combined biocompatible and mechanical characteristics. However, to realize such plasticity external complicated treatments, e.g., UV or organic solvent have to be applied, which in turn impair the biological nature and even mechanical properties of those systems. To address this challenge, one new type of anhydrous protein liquid crystalline (LC) gels, which exhibit flexible morphological plasticity and mechanical programmability is demonstrated. Supramolecular interactions in the smectic biogels play an important role for their high plasticity. Remarkably, the samples exhibit outstanding mechanical behaviors. The tensile strength and Young's modulus at MPa levels are comparable or even higher than chemically cross-linked hydrogels and LC elastomers. More importantly, mechanical programmability of the LC gels is achieved by genetically tuning the charge density of protein backbones. Consequently, the mechanical performance is manipulated in the range of one order of magnitude. Thus, this type of anhydrous protein LC gels offers great opportunities for load-bearing high-tech applications
Antiurolithiatic effect of ferulic acid on ethylene glycolinduced renal calculus in experimental rats
Purpose: To evaluate the anti-urolithiatic effect of ferulic acid on ethylene glycol-induced kidney stone in a rat model.Methods: Five groups of adult male Sprague-Dawley rats (6 rats/group) were used in this study. Group I rats served as normal control. Renal calculus was induced through ethylene glycol (0.75 % v/v in drinking water) administration to all rats for 28 days except those in group 1. Prior to ethylene glycol treatment, ferulic acid was given orally (gavage) to rats in groups III and IV at doses of 40 and 80 mg/kg, respectively. Rats in group V (positive control) were treated with standard drug, cystone at a dose of 750 mg/kg prior to ethylene glycol administration, while group II rats received no treatment. Kidney tissue and blood serum were sampled after 28 days and used for biochemical and histopathological analyses.Results: Rats in group II showed significant increases in oxidative stress pattern as seen in significant reductions in GSH, SOD, GPx, and CAT levels, and significant elevation of lipid peroxidation (LPO), relative to normal control group (p < 0.05). However, renal calculus formation and oxidative stress were significantly inhibited by ferulic acid treatment in groups III and IV. These results were supported by histopathological findings.Conclusion: Ferulic acid exerts anti-urolithiatic effect via inhibition of oxidative stress. Thus, it has potentials for use in preventing kidney stone formation.Keywords: Urolithiasis, Ferulic acid, Ethylene glycol, Kidney, Histopatholog
Radio Polarization of BL Lacertae objects
In this paper, using the database of the university of Michigan Radio
Astronomy Observatory (UMRAO) at three (4.8 GHz, 8 GHZ, and 14.5 GHz) radio
frequencies, we studied the polarization properties for 47 BL Lacertae
objects(38 radio selected BL Lacertae objects, 7 X-ray selected BL Lacertae,
and two inter-middle objects (Mkn 421 and Mkn 501), and found that (1) The
polarizations at higher radio frequency is higher than those at lower
frequency, (2) The variability of polarization at higher radio frequency is
higher than those at lower frequency, (3) The polarization is correlated with
the radio spectral index, and (4) The polarization is correlated with
core-dominance parameter for those objects with known core-dominance parameters
suggesting that the relativistic beaming could explain the polarization
characteristic of BL Lacs.Comment: 5 pages, 3 figures, 1 table. PASJ, in pres
- …