Design of Virtual Objects Using Transformation Optics

Two structures of virtual targets filled with metamaterials are investigated through transformation optics to tailor the specific electromagnetic fields into desired spatial patterns. One virtual structure is a square column object transformed from a dielectric cylinder and the other virtual structure is a cylinder object transformed from a dielectric square column. Because the electromagnetic parameters in the virtual objects are obtained from real objects by the method of transformation optics, the scattering fields of virtual structures are the same as those of the real objects. The numerical simulations further prove the correction of theoretical results

Carbon monoxide in an extremely metal-poor galaxy

Extremely metal-poor galaxies with metallicity below 10% of the solar value in the local universe are the best analogues to investigating the interstellar medium at a quasi-primitive environment in the early universe. In spite of the ongoing formation of stars in these galaxies, the presence of molecular gas (which is known to provide the material reservoir for star formation in galaxies, such as our Milky Way) remains unclear. Here, we report the detection of carbon monoxide (CO), the primary tracer of molecular gas, in a galaxy with 7% solar metallicity, with additional detections in two galaxies at higher metallicities. Such detections offer direct evidence for the existence of molecular gas in these galaxies that contain few metals. Using archived infrared data, it is shown that the molecular gas mass per CO luminosity at extremely low metallicity is approximately one-thousand times the Milky Way value.Comment: 12 pages, 3 figures, 1 table. Supplementary data at http://www.nature.com/article-assets/npg/ncomms/2016/161209/ncomms13789/extref/ncomms13789-s1.pd

The Role of Deubiquitinases in DNA Double-Strand Break Repair

DNA double-strand break (DSB) is a type of the most critical DNA lesions, and if not repaired promptly, it can result in cell death or a wide variety of genetic alterations including genome instability, large- or small-scale deletions, chromosome loss, loss of heterozygosity, and translocations. DSBs are repaired by double-strand break repair (DSBR), including nonhomologous end-joining (NHEJ) and homologous recombination (HR) pathway, and defects in these pathways cause genome instability and promote tumorigenesis. Accumulating evidence has demonstrated that the superfamily of deubiquitinases (DUBs) can regulate the action and stability of DNA repair enzymes involving in DSBR via modifying ubiquitination levels, a reversible posttranslational modification pathway. In this review, we will discuss ubiquitination/deubiquitination modification involving in DSBR genes, the role of DUBs in DSBR and corresponding mechanisms, and the potential effects of this modification on human diseases

Pioglitazone Upregulates Angiotensin Converting Enzyme 2 Expression in Insulin-Sensitive Tissues in Rats with High-Fat Diet-Induced Nonalcoholic Steatohepatitis

Background and Aim. Thiazolidinediones (TZDs) can improve hepatic steatosis in nonalcoholic steatohepatitis (NASH). Angiotensin (Ang) II, the primary effector of renin-angiotensin system (RAS), plays vital roles in the development and progression of NASH. And some AngII-mediated effects can be regulated by TZDs. Angiotensin-converting enzyme (ACE) 2, a new component of RAS, can degrade Ang II to attenuate its subsequent physiological actions. We aimed to evaluate the effects of TZDs on ACE2 expression in insulin-sensitive tissues in NASH rats. Methods. Forty rats were divided into the normal control, high-fat diet (HFD), pioglitazone control, and HFD plus pioglitazone groups. After 24 weeks of treatment, we evaluated changes in liver histology and tissue-specific ACE2 expression. Results. ACE2 gene and protein expression was significantly greater in liver and adipose tissue in the HFD group compared with normal control group, while was significantly reduced in skeletal muscle. Pioglitazone significantly reduced the degree of hepatic steatosis compared with the HFD group. Pioglitazone significantly increased ACE2 protein expression in liver, adipose tissue, and skeletal muscle compared with the HFD group. Conclusions. Pioglitazone improves hepatic steatosis in the rats with HFD-induced NASH and upregulates ACE2 expression in insulin-sensitive tissues

No relationship between the distribution of mast cells and the survival of stage IIIB colon cancer patients

<p>Abstract</p> <p>Background</p> <p>Mast cells promote the progression of experimental tumors and might be a valuable therapeutic target. However, the relevant clinical evidence is still controversial. This study analyzed the relationship between the distribution of mast cells and the survival of patients with colon cancer to study whether mast cells contribute to tumor progression.</p> <p>Materials and methods</p> <p>Ninety-three cases of pathologically confirmed primary cancer tissues matched with adjacent normal mucosa, metastases of regional-draining lymph nodes and regional-draining lymph nodes without metastases were collected from stage IIIB colon carcinoma patients between January 1997 and July 2004 at the Cancer Center of Sun Yat-Sen University. Tryptase-positive mast cells were counted. The relationships of the distribution of mast cells with clinicopathologic parameters and 5-year survival were analyzed.</p> <p>Results</p> <p>Although the mast cell count in the mucosa adjacent to the primary colon cancer was significantly higher than that in the stroma of the primary colon cancer, no difference in mast cell counts was observed between the stroma in lymph node metastasis and the lymph tissue adjacent to the metastasis. Additionally, the mast cell count in the regional-draining lymph node without the invasion of cancer cells was significantly higher than that in the stroma of lymph node metastasis and adjacent lymph tissue. However, none of those mast cell counts was related to 5-year survival.</p> <p>Conclusion</p> <p>Although mast cell count varied with location, none of the mast cell counts was related to 5-year survival, suggesting that mast cells do not contribute to the progression of stage IIIB colon cancer.</p

Tetra­aqua­{1-[(1H-1,2,3-benzotriazol-1-yl)meth­yl]-1H-1,2,4-triazole}sulfato­zinc(II) dihydrate

In the title complex, [Zn(SO4)(C9H8N6)(H2O)4]·2H2O, the ZnII ion is six-coordinated by one N atom from a 1-[(1H-1,2,3-benzotriazol-1-yl)meth­yl]-1H-1,2,4-triazole ligand and five O atoms from one monodentate sulfate anion and four water mol­ecules in a distorted octa­hedral geometry. The sulfate tetra­hedron is rotationally disordered over two positions in a 0.618 (19):0.382 (19) ratio. In the crystal, adjacent mol­ecules are linked through O—H⋯O and O—H⋯N hydrogen bonds involving the cation, the anion, and the coordinated and uncoordinated water mol­ecules into a three-dimensional network

The double charm decays of B Mesons in the mSUGRA model

Based on the low energy effective Hamiltonian with naive factorization, we calculate the branching ratios(BRs) and CP asymmetries (CPAs) for the twenty three double charm decays $B/B_s \to D^{(*)}_{(s)} D^{(*)}_{(s)}$ in both the standard model (SM) and the minimal supergravity (mSUGRA) model. Within the considered parameter space, we find that (a) the theoretical predictions for the BRs, CPAs and the polarization fractions in the SM and the mSUGRA model are all consistent with the currently available data within $\pm 2\sigma$ errors; (b) For all the considered decays, the supersymmetric contributions in the mSUGRA model are very small, less than $7\%$ numerically. It may be difficult to observe so small SUSY contributions even at LHC.Comment: 15 pages, 5tables, no figure

Extramedullary versus intramedullary tibial alignment technique in total knee arthroplasty: A meta-analysis of randomized controlled trials

The aim of this study was to establish whether the use of an extramedullary or intramedullary tibial cutting guide leads to superior mechanical leg axis and implant positioning. A meta-analysis of six randomized controlled trials including 350 knees was performed. For the mechanical axis, frontal tibial component angle and tibial slope, there were no significant differences in the mean values or the number of outliers (±3°) between the extramedullary and intramedullary groups. A reduced tourniquet time was associated with the intramedullary guide. No significant difference in the complication rate was noted between the two groups. Neither extramedullary nor intramedullary tibial alignment was more accurate in facilitating the tibial cut. Use of an intramedullary guide results in a shorter tourniquet time and exhibits a similar complication rate as the extramedullary guide

Strangeon matter and strangeon stars in a linked bag model

Inspired by various astrophysical phenomenons, it was suggested that pulsar-like compact stars may in fact be strangeon stars, comprised entirely of strangeons (quark-clusters with three-light-flavor symmetry) and a small amount of electrons. To examine such possibilities, in this work we propose a linked bag model, which can be adopted for strong condensed matter in both 2-flavoured (nucleons) and 3-flavoured (hyperons, strangeons, etc.) scenarios. The model parameters are calibrated to reproduce the saturation properties of nuclear matter, which are later applied to hyperonic matter and strangeon matter. The obtained energy per baryon of strangeon matter is reduced if we adopt larger quark numbers inside a strangeon, which stiffens the equation of state and consequently increases the maximum mass of strangeon stars. In a large parameter space, the maximum mass and tidal deformability of strangeon stars predicted in the linked bag model are consistent with the current astrophysical constraints. It is found that the maximum mass of strangeon stars can be as large as $\sim 2.5M_\odot$, while the tidal deformability of a $1.4M_\odot$ strangeon star lies in the range of $180\lesssim \Lambda_{1.4} \lesssim 340$. More refined theoretical efforts as well as observational tests to these results are necessary in the future