An event detection approach based on Twitter hashtags

Twitter is one of the most popular microblogging services in the world. The great amount of information made Twitter an important information channel for people to know and share news. Hashtag is a popular feature when people use Twitter. It can be taken as human labeled information and is useful for people to identify the topic of a tweet. Many researchers have proposed event-detection approaches that can monitor Twitter data and determine whether special events, such as accidents, extreme weather, earthquakes, or crimes, are happening. Although many approaches considered hashtag as one of their features, few of them explicitly focused on the effectiveness of using hashtag on event detection. In this study, we proposed an event detection approach that utilizes hashtags in tweets. We adopted the feature extraction used in STREAMCUBE (Feng et al., 2015) and applied a clustering K-means approach (Lloyd, 1982) to it. The experiments were conducted on 20,514 tweets with 8,616 hashtags collected between November 13, 2015 and November 17, 2015 with general topic of the Paris Attacks. A randomly sampled subset of 200 tweets was also manually labeled by a human subject to verify the approach. Based on the collected tweets, we demonstrated that the K-means approach could perform better than STREAMCUBE in the clustering results. Also, we discussed how to set the K values for the K-means approach to lead to a better clustering performance

Convergence of quantum random walks with decoherence

In this paper, we study the discrete-time quantum random walks on a line subject to decoherence. The convergence of the rescaled position probability distribution $p(x,t)$ depends mainly on the spectrum of the superoperator $\mathcal{L}_{kk}$. We show that if 1 is an eigenvalue of the superoperator with multiplicity one and there is no other eigenvalue whose modulus equals to 1, then $\hat {P}(\frac{\nu} {\sqrt t},t)$ converges to a convex combination of normal distributions. In terms of position space, the rescaled probability mass function $p_t (x, t) \equiv p(\sqrt t x, t)$, $x \in Z/\sqrt t$, converges in distribution to a continuous convex combination of normal distributions. We give an necessary and sufficient condition for a U(2) decoherent quantum walk that satisfies the eigenvalue conditions. We also give a complete description of the behavior of quantum walks whose eigenvalues do not satisfy these assumptions. Specific examples such as the Hadamard walk, walks under real and complex rotations are illustrated. For the O(2) quantum random walks, an explicit formula is provided for the scaling limit of $p(x,t)$ and their moments. We also obtain exact critical exponents for their moments at the critical point and show universality classes with respect to these critical exponents

Structural elucidation of phosphoglycolipids from strains of the bacterial thermophiles Thermus and Meiothermus.

The structures of two major phosphoglycolipids from the thermophilic bacteria Thermus oshimai NTU-063, Thermus thermophilus NTU-077, Meiothermus ruber NTU-124, and Meiothermus taiwanensis NTU-220 were determined using spectroscopic and chemical analyses to be 2'-O-(1,2-diacyl-sn-glycero-3-phospho) -3'-O-(alpha-N-acetyl-glucosaminyl)-N-glyceroyl alkylamine [PGL1 (1)] and the novel structure 2'-O-(2-acylalkyldio-1-O-phospho)-3'-O-(alpha-N-acetylglucosaminyl)-N-glyceroyl alkylamine [PGL2 (2)]. PGL2 (2) is the first phosphoglycolipid identified with a 2-acylalkyldio-1-O-phosphate moiety. The fatty acids of the phosphoglycolipids are mainly iso-C(15:0), -C(16:0), and -C(17:0) and anteiso-C(15:0) and -C(17:0). The ratios of PGL2 (2) to PGL1 (1) are significantly altered when grown at different temperatures for three strains, T. thermophilus NTU-077, M. ruber NTU-124, and M. taiwanensis NTU-220, but not for T. oshimai NTU-063. Accordingly, the ratios of iso- to anteiso-branched fatty acids increase when grown at the higher temperature

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) interaction with 3' ends of Japanese encephalitis virus RNA and colocalization with the viral NS5 protein

Replication of the Japanese encephalitis virus (JEV) genome depends on host factors for successfully completing their life cycles; to do this, host factors have been recruited and/or relocated to the site of viral replication. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a cellular metabolic protein, was found to colocalize with viral RNA-dependent RNA polymerase (NS5) in JEV-infected cells. Subcellular fractionation further indicated that GAPDH remained relatively constant in the cytosol, while increasing at 12 to 24 hours postinfection (hpi) and decreasing at 36 hpi in the nuclear fraction of infected cells. In contrast, the redistribution patterns of GAPDH were not observed in the uninfected cells. Co-immunoprecipitation of GAPDH and JEV NS5 protein revealed no direct protein-protein interaction; instead, GAPDH binds to the 3' termini of plus- and minus-strand RNAs of JEV by electrophoretic mobility shift assays. Accordingly, GAPDH binds to the minus strand more efficiently than to the plus strand of JEV RNAs. This study highlights the findings that infection of JEV changes subcellular localization of GAPDH suggesting that this metabolic enzyme may play a role in JEV replication

Dedifferentiated liposarcoma can induce a leukemoid reaction

SummaryLiposarcoma is one of the most common malignant soft tissue neoplasms in adults; however, few reports of liposarcoma had been described the expression of leukocytosis and granulocyte-colony stimulating factor (G-CSF). In this report, we present the rare case of a patient who had de-differentiated liposarcoma and elevated G-CSF levels that resulted in a leukemoid reaction. The patient was a 65-year-old man who had been lame for one month due to right thigh swelling. His body temperature was slightly elevated at 38°C and leukocytosis with an elevated white blood cell (WBC) count (41500/μL) was noted. The findings of computed tomography of the lower extremities indicated the presence of a malignancy. Therefore, an incision biopsy was performed. Based on the finding of magnetic resonance imaging (MRI) and the biopsy pathology report, we diagnosed the patient with liposarcoma. Moreover, the preoperative serum G-CSF level was elevated (261.8 pg/mL). An en bloc excision including the entire biopsy pathway was performed 5 days after admission. After en bloc excision of the tumor, WBC count, C-reactive protein (CRP) level, and G-CSF expression decreased. The final pathologic report confirmed the diagnosis of de-differentiated liposarcoma. No local recurrence or distant metastasis was detected in the follow-up image study, and the patient has remained asymptomatic 2 years after surgery. The case described here is a rare type of liposarcoma that produces G-CSF, which in turn, induces leukocytosis. Liposarcoma with elevated G-CSF levels resulting in a leukemoid reaction may indicate a poorly differentiated cell type and may be associated with a poor prognosis; however, en bloc excision of the tumor remains the primary treatment for this type of tumor. Moreover, the WBC count and G-CSF serum level can be as the tools monitoring the tumor recurrence

Temporal Arteritis

Temporal arteritis, a chronic inflammatory vasculitis involving medium- and large-sized arteries, has rarely been reported in Asia. However, we report 2 cases, in which the patients initially presented with headache. Physical examination disclosed engorged, hard and palpable vessels in the temporal areas. Temporal-artery biopsy revealed 2 different types of arteritis: the multinucleated giant cell type and the panarteritis type without multinucleated giant cells. One patient was positive for immunoglobulin G anticardiolipin antibody. The pathologic findings of the different subsets of temporal arteritis, and the relationship between anticardiolipin antibody and the extent of vascular complications of temporal arteritis, are discussed

Morphological and Molecular Defects in Human Three-Dimensional Retinal Organoid Model of X-Linked Juvenile Retinoschisis

X-linked juvenile retinoschisis (XLRS), linked to mutations in the RS1 gene, is a degenerative retinopathy with a retinal splitting phenotype. We generated human induced pluripotent stem cells (hiPSCs) from patients to study XLRS in a 3D retinal organoid in vitro differentiation system. This model recapitulates key features of XLRS including retinal splitting, defective retinoschisin production, outer-segment defects, abnormal paxillin turnover, and impaired ER-Golgi transportation. RS1 mutation also affects the development of photoreceptor sensory cilia and results in altered expression of other retinopathy-associated genes. CRISPR/Cas9 correction of the disease-associated C625T mutation normalizes the splitting phenotype, outer-segment defects, paxillin dynamics, ciliary marker expression, and transcriptome profiles. Likewise, mutating RS1 in control hiPSCs produces the disease-associated phenotypes. Finally, we show that the C625T mutation can be repaired precisely and efficiently using a base-editing approach. Taken together, our data establish 3D organoids as a valid disease model