On character table of Clifford groups

Based on a presentation of $\mathcal{C}_n$ and the help of [GAP], we construct the character table of the Clifford group $\mathcal{C}_n$ for $n=1,2,3$. As an application, we can efficiently decompose the (higher power of) tensor product of the matrix representation in those cases. Our results recover some known results in [HWW, WF] and reveal some new phenomena. We prove that the trivial character is the only linear character for $\mathcal{C}_n$ and hence $\mathcal{C}_n$ equals to its commutator subgroup when $n\geq 3$. A few conjectures about $\mathcal{C}_n$ for general $n$ are proposed.Comment: 13 pages; comments and suggestions are welcom

Spontaneous Dissecting Aneurysm of the Renal Artery: A Case Report

Primary dissecting aneurysms of the renal artery are exceedingly rare. The triad of flank pain, hematuria, and hypertension of acute onset in the absence of urinary obstruction should suggest this rare condition. We report a case of spontaneous dissecting aneurysm of the renal artery treated using conservative medical treatment. The diagnosis, therapeutic management, and outcome are discussed

Atomically-thin metallic Si and Ge allotropes with high Fermi velocities

Silicon and germanium are the well-known materials used to manufacture electronic devices for the integrated circuits but they themselves are not considered as promising options for interconnecting the devices due to their semiconducting nature. We have discovered that both Si and Ge atoms can form unexpected metallic monolayer structures which are more stable than the extensively studied semimetallic silicene and germanene, respectively. More importantly, the newly discovered two-dimensional allotropes of Si and Ge have Fermi velocities superior to the Dirac fermions in graphene, indicating that the metal wires needed in the silicon-based integrated circuits can be made of Si atom itself without incompatibility, allowing for all-silicon-based integrated circuits.Comment: 10 pages, 3 figures, 1 tabl

Differential evolutionary conservation of motif modes in the yeast protein interaction network

BACKGROUND: The importance of a network motif (a recurring interconnected pattern of special topology which is over-represented in a biological network) lies in its position in the hierarchy between the protein molecule and the module in a protein-protein interaction network. Until now, however, the methods available have greatly restricted the scope of research. While they have focused on the analysis in the resolution of a motif topology, they have not been able to distinguish particular motifs of the same topology in a protein-protein interaction network. RESULTS: We have been able to assign the molecular function annotations of Gene Ontology to each protein in the protein-protein interactions of Saccharomyces cerevisiae. For various motif topologies, we have developed an algorithm, enabling us to unveil one million "motif modes", each of which features a unique topological combination of molecular functions. To our surprise, the conservation ratio, i.e., the extent of the evolutionary constraints upon the motif modes of the same motif topology, varies significantly, clearly indicative of distinct differences in the evolutionary constraints upon motifs of the same motif topology. Equally important, for all motif modes, we have found a power-law distribution of the motif counts on each motif mode. We postulate that motif modes may very well represent the evolutionary-conserved topological units of a protein interaction network. CONCLUSION: For the first time, the motifs of a protein interaction network have been investigated beyond the scope of motif topology. The motif modes determined in this study have not only enabled us to differentiate among different evolutionary constraints on motifs of the same topology but have also opened up new avenues through which protein interaction networks can be analyzed

Knockdown of PsbO leads to induction of HydA and production of photobiological H2 in the green alga Chlorella sp. DT

Green algae are able to convert solar energy to H2 via the photosynthetic electron transport pathway under certain conditions. Algal hydrogenase (HydA, encoded by HYDA) is in charge of catalyzing the reaction: 2H+ + 2e− ↔ H2 but usually inhibited by O2, a byproduct of photosynthesis. The aim of this study was to knockdown PsbO (encoded by psbO), a subunit concerned with O2 evolution, so that it would lead to HydA induction. The alga, Chlorella sp. DT, was then transformed with short interference RNA antisense-psbO (siRNA-psbO) fragments. The algal mutants were selected by checking for the existence of siRNA-psbO fragments in their genomes and the low amount of PsbO proteins. The HYDA transcription and the HydA expression were observed in the PsbO-knockdown mutants. Under semi-aerobic condition, PsbO-knockdown mutants could photobiologically produce H2 which increased by as much as 10-fold in comparison to the wild type

Inhibition of Mitochondria- and Endoplasmic Reticulum Stress-Mediated Autophagy Augments Temozolomide-Induced Apoptosis in Glioma Cells

Autophagy is a crucial process for cells to maintain homeostasis and survival through degradation of cellular proteins and organelles, including mitochondria and endoplasmic reticula (ER). We previously demonstrated that temozolomide (TMZ), an alkylating agent for brain tumor chemotherapy, induced reactive oxygen species (ROS)/extracellular signal-regulated kinase (ERK)-mediated autophagy to protect glioma cells from apoptosis. In this study, we investigated the role of mitochondrial damage and ER stress in TMZ-induced cytotoxicity. Mitochondrial depolarization and mitochondrial permeability transition pore (MPTP) opening were observed as a prelude to TMZ-induced autophagy, and these were followed by the loss of mitochondrial mass. Electron transport chain (ETC) inhibitors, such as rotenone (a complex I inhibitor), sodium azide (a complex IV inhibitor), and oligomycin (a complex V inhibitor), or the MPTP inhibitor, cyclosporine A, decreased mitochondrial damage-mediated autophagy, and therefore increased TMZ-induced apoptosis. TMZ treatment triggered ER stress with increased expression of GADD153 and GRP78 proteins, and deceased pro-caspase 12 protein. ER stress consequently induced autophagy through c-Jun N-terminal kinases (JNK) and Ca2+ signaling pathways. Combination of TMZ with 4-phenylbutyrate (4-PBA), an ER stress inhibitor, augmented TMZ-induced cytotoxicity by inhibiting autophagy. Taken together, our data indicate that TMZ induced autophagy through mitochondrial damage- and ER stress-dependent mechanisms to protect glioma cells. This study provides evidence that agents targeting mitochondria or ER may be potential anticancer strategies

The Relationship between Brown Adipose Tissue Activity and Neoplastic Status: an 18F-FDG PET/CT Study in the Tropics

<p>Abstract</p> <p>Background</p> <p>Brown adipose tissue (BAT) has thermogenic potential. For its activation, cold exposure is considered a critical factor though other determinants have also been reported. The purpose of this study was to assess the relationship between neoplastic status and BAT activity by 2-deoxy-2-[18F]fluoro-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) in people living in the tropics, where the influence of outdoor temperature was low.</p> <p>Methods</p> <p>¹⁸F-FDG PET/CT scans were reviewed and the total metabolic activity (TMA) of identified activated BAT quantified. The distribution and TMA of activated BAT were compared between patients with and without a cancer history. The neoplastic status of patients was scored according to their cancer history and ¹⁸F-FDG PET/CT findings. We evaluated the relationships between the TMA of BAT and neoplastic status along with other factors: age, body mass index, fasting blood sugar, gender, and outdoor temperature.</p> <p>Results</p> <p>Thirty of 1740 patients had activated BAT. Those with a cancer history had wider BAT distribution (<it>p </it>= 0.043) and a higher TMA (<it>p </it>= 0.028) than those without. A higher neoplastic status score was associated with a higher average TMA. Multivariate analyses showed that neoplastic status was the only factor significantly associated with the TMA of activated BAT (<it>p </it>= 0.016).</p> <p>Conclusions</p> <p>Neoplastic status is a critical determinant of BAT activity in patients living in the tropics. More active neoplastic status was associated with more vigorous TMA of BAT.</p

Initial Presentations Predict Mortality in Pulmonary Tuberculosis Patients - A Prospective Observational Study

Despite effective anti-TB treatments, tuberculosis remains a serious threat to public health and is associated with high mortality. Old age and multiple co-morbidities are known risk factors for death. The association of clinical presentations with mortality in pulmonary tuberculosis patients remains an issue of controversy.This prospective observational study enrolled newly diagnosed, culture-proven pulmonary tuberculosis patients from five medical centers and one regional hospital, which were referral hospitals of TB patients. Radiographic findings and clinical symptoms were determined at the time of diagnosis. Patients who died for any reason during the course of anti-TB treatment were defined as mortality cases and death that occurred within 30 days of initiating treatment was defined as early mortality. Clinical factors associated with overall mortality and early mortality were investigated.A total of 992 patients were enrolled and 195 (19.7%) died. Nearly one-third (62/195, 31.8%) of the deaths occurred before or within 30 days of treatment initiation. Older age (RR = 1.04, 95%CI: 1.03–1.05), malignancy (RR = 2.42, 95%CI: 1.77–3.31), renal insufficiency (RR = 1.77, 95%CI: 1.12–2.80), presence of chronic cough (RR = 0.63, 95%CI: 0.47–0.84), fever (RR = 1.45, 95%CI: 1.09–1.94), and anorexia (RR = 1.49, 95%CI: 1.07–2.06) were independently associated with overall mortality. Kaplan-Meier survival analysis demonstrated significantly higher mortality in patients present with fever (p<0.001), anorexia (p = 0.005), and without chronic cough (p<0.001). Among patients of mortality, those with respiratory symptoms of chronic cough (RR = 0.56, 95%CI: 0.33–0.98) and dyspnea (HR = 0.51, 95%CI: 0.27–0.98) were less likely to experience early mortality. The radiological features were comparable between survivors and non-survivors.In addition to demographic characteristics, clinical presentations including the presence of fever, anorexia, and the absence of chronic cough, were also independent predictors for on-treatment mortality in pulmonary tuberculosis patients