2,995 research outputs found
GeV Scale Asymmetric Dark Matter from Mirror Universe: Direct Detection and LHC Signatures
Mirror universe is a fundamental way to restore parity symmetry in weak
interactions. It naturally provides the lightest mirror nucleon as a unique
GeV-scale asymmetric dark matter particle candidate. We conjecture that the
mirror parity is respected by the fundamental interaction Lagrangian, and its
possible soft breaking arises only from non-interaction terms in the
gauge-singlet sector. We realize the spontaneous mirror parity violation by
minimizing the vacuum Higgs potential, and derive the corresponding Higgs
spectrum. We demonstrate that the common origin of CP violation in the visible
and mirror neutrino seesaws can generate the right amount of matter and mirror
dark matter via leptogenesis. We analyze the direct detections of GeV-scale
mirror dark matter by TEXONO and CDEX experiments. We further study the
predicted distinctive Higgs signatures at the LHC.Comment: 16pp. Plenary talk presented by HJH at the International Symposium on
Cosmology and Particle Astrophysics (CosPA2011). To appear in the conference
proceedings of IJMP. Minor refinement
Eisenia fetida Protease-III-1 Functions in Both Fibrinolysis and Fibrogenesis
The fibrinolytic function of earthworm protease-III-1 (Ef P-III-1) has been studied in recent years. Here, we found that Ef P-III-1 acted not only in fibrinogenolysis, but also in fibrogenesis. We have used Ef P-III-1 to hydrolyze fibrinogen, and to activate plasminogen and prothrombin. Based on the N-terminal sequences of the hydrolytic fragments, Ef P-III-1 was showed to specifically recognize the carboxylic sites of arginine and lysine. Analyses by fibrinogenolysis mapping and amino acid sequencing revealed that the isozyme could cleave the alpha, beta, and gamma chains of fibrinogen, showing a high α-fibrinogenase, moderate β-fibrinogenase, and low γ-fibrinogenase activities. Interestingly, Ef P-III-1 activated plasminogen and released active plasmin, suggesting a tPA-like function. Furthermore, Ef P-III-1 showed a factor Xa-like function on prothrombin, producing alpha-thrombin. The function in both activating prothrombin and catalyzing fibrinogenolysis suggests that Ef P-III-1 may play a role in the balance between procoagulation and anticoagulation
No mixed graph with the nullity
A mixed graph is obtained from a simple undirected graph ,
the underlying graph of , by orienting some edges of . Let
be the cyclomatic number of with
the number of connected components of , be the matching number of
, and be the nullity of . Chen et al.
(2018)\cite{LSC} and Tian et al. (2018)\cite{TFL} proved independently that
,
respectively, and they characterized the mixed graphs with nullity attaining
the upper bound and the lower bound. In this paper, we prove that there is no
mixed graph with nullity . Moreover,
for fixed , there are infinitely many connected mixed graphs with nullity
is proved
(E)-N-(4-Chlorobenzylidene)-5-(4-methylphenyl)-1,3,4-thiadiazol-2-amine
The title compound, C16H12ClN3S, was synthesized by the reaction of 5-(4-methylphenyl)-1,3,4-thiadiazol-2-amine and 4-chlorobenzaldehyde. The thiadiazole ring is essentially planar with mean deviation of 0.0042 Å
5-(4-Bromo-2-nitrophenyl)-1,3,4-thiadiazol-2-amine
The title compound, C8H5BrN4O2S, was synthesized by the reaction of 4-bromo-2-nitrobenzoic acid with thiosemicarbazide. The dihedral angle between the thiadiazole and benzene rings is 40.5 (2)°. In the crystal, the strongest N—H⋯N intermolecular hydrogen bond, between the amine group and one thiadiazole N atom, forms centrosymmetric dimers. The other amine H atom extends the supramolecular network, forming an N—H⋯N contact with the other thiadiazole N atom
Characterizing and Predicting Early Reviewers for Effective Product Marketing on E-Commerce Websites
Online reviews have become an important source of information for users before making an informed purchase decision. Early reviews of a product tend to have a high impact on the subsequent product sales. In this paper, we take the initiative to study the behavior characteristics of early reviewers through their posted reviews on two real-world large e-commerce platforms, i.e., Amazon and Yelp. In specific, we divide product lifetime into three consecutive stages, namely early, majority and laggards. A user who has posted a review in the early stage is considered as an early reviewer. We quantitatively characterize early reviewers based on their rating behaviors, the helpfulness scores received from others and the correlation of their reviews with product popularity. We have found that (1) an early reviewer tends to assign a higher average rating score; and (2) an early reviewer tends to post more helpful reviews. Our analysis of product reviews also indicates that early reviewers' ratings and their received helpfulness scores are likely to influence product popularity. By viewing review posting process as a multiplayer competition game, we propose a novel margin-based embedding model for early reviewer prediction. Extensive experiments on two different e-commerce datasets have shown that our proposed approach outperforms a number of competitive baselines
2,2-Dimethyl-5-[(pyridin-2-ylamino)methylidene]-1,3-dioxane-4,6-dione
In the title compound, C12H12N2O4, the dihedral angle between the pyridine and enamine planes is 3.5 (3)°, while the angle between the dioxanedione (seven atoms) and enamine planes is 4.6 (3)°. The dioxane ring approximates an envelope conformation
5-(1H-Indol-3-ylmethylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione
In the title compound, C15H13NO4, the conjugated double-bond system between the two rings adopts a cis configuration and there is an intramolecular indole–ketone C—H⋯O interaction. The indole N—H group forms an intermolecular hydrogen bond with a ketone O-atom acceptor, giving a chain structure along the ab direction. The O-heterocyclic ring adopts a boat conformation and makes a dihedral angle of 16.72 (6)° with the indole ring system
Incorporating social role theory into topic models for social media content analysis
In this paper, we explore the idea of social role theory (SRT) and propose a novel regularized topic model which incorporates SRT into the generative process of social media content. We assume that a user can play multiple social roles, and each social role serves to fulfil different duties and is associated with a role-driven distribution over latent topics. In particular, we focus on social roles corresponding to the most common social activities on social networks. Our model is instantiated on microblogs, i.e., Twitter and community question-answering (cQA), i.e., Yahoo! Answers, where social roles on Twitter include "originators" and "propagators", and roles on cQA are "askers" and "answerers". Both explicit and implicit interactions between users are taken into account and modeled as regularization factors. To evaluate the performance of our proposed method, we have conducted extensive experiments on two Twitter datasets and two cQA datasets. Furthermore, we also consider multi-role modeling for scientific papers where an author's research expertise area is considered as a social role. A novel application of detecting users' research interests through topical keyword labeling based on the results of our multi-role model has been presented. The evaluation results have shown the feasibility and effectiveness of our model
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