Atomic Resolution Imaging of Rotated Bilayer Graphene Sheets Using a Low kV Aberration-corrected Transmission Electron Microscope

Modern aberration-corrected transmission electron microscope (TEM) with appropriate electron beam energy is able to achieve atomic resolution imaging of single and bilayer graphene sheets. Especially, atomic configuration of bilayer graphene with a rotation angle can be identified from the direct imaging and phase reconstructed imaging since atomic resolution Moir pattern can be obtained successfully at atomic scale using an aberration-corrected TEM. This study boosts a reliable stacking order analysis, which is required for synthesized or artificially prepared multilayer graphene, and lets graphene researchers utilize the information of atomic configuration of stacked graphene layers readily.ope

Creep and Oxidation Behaviors of Alloy 617 in Air and Helium Environments at 1173K

AbstractCreep and oxidation behaviours of Alloy 617 in air and helium (He) environments at 1173K were comparatively investigated under different applied stress levels. There were no large differences in the shapes of the creep curves between the air and He environments. Creep rupture time in the He environment was shorter than that in air. The outer Cr-oxide thickness of the air specimens was thicker in short-tested duration than that of the He specimens. However, in the long- tested duration over 3,000h, the Cr-oxide thickness in the He environment was larger than in air. It was found that creep rupture life was closely related to the thickness of the outer Cr-oxide layer, because the form of the outer Cr-rich oxide layer brings about the Cr-depleted region which may deteriorate material strength or creep life

Enhancement on Radon Adsorption Property of GAC using Nano-size Carbon Colloids

Granular activated carbon (GAC) is well-known as an efficient adsorbent against a number of gaseous pollutants. Radon is one of those pollutants, and radon has been classified as the second leading cause of lung cancer in USA. This study was to enhance the radon removal efficiency with applying nano-technology. Nano-size carbon colloids (NCC) was produced through electrolysis which is simple and cheap. NCC was used for impregnation with activated carbon. Surface areas of both NCC-treated and non-treated activated carbon did not show a significant difference. However, the results of radon removal efficiency show that impregnated carbon with NCC could capture about 1.3 ~ 2 times of more radon gas compared to non-treated activated carbon. It is assumed that nano-size carbon colloids might have filled up meso-pores, and meso-pores turned into micro-pores eventually. Because meso-pores initially accounted for large portion of whole pores, more radon could be captured to NCC-impregnated activated carbon. Keywords: Radon, Nano-Size Carbon Collid, Activated Carbo

Preparation and Characterization of Self-Emulsified Docetaxel

The aim of this paper was to prepare a self-microemulsifying docetaxel (Dtx) using PLGA, Tetraglycol, Labrasol, and Cremophor ELP. The prepared Dtx-loaded self-microemulsifying system (SMES) showed the initial size of the range of 80–100 nm with narrow size distribution and the negative zeta-potential values. Its morphology was a spherical shape by atomic force microscopy. In experiment of stability, Dtx-loaded SMES prepared in DW and BSA condition showed good stability at 37∘C for 7 days. The viability of the B16F10 cells incubated with Dtx-loaded SMES, Dtx-solution, and Taxol were decreased as a function of incubation time. In conclusion, we confirmed that Dtx-loaded SMES showed an inhibitory effect for proliferation of B16F10 melanoma cells

First Successful Application of Preimplantation Genetic Diagnosis for Lethal Neonatal Rigidity and Multifocal Seizure Syndrome in Korea: A Case Report

Lethal neonatal rigidity and multifocal seizure syndrome (RMFSL) is a severe autosomal recessive epileptic encephalopathy characterized by rigidity, intractable multifocal seizures, microcephaly, apnea, and bradycardia immediately after birth. RMFSL is related to a mutation in breast cancer 1-associated ataxia telangiectasia mutated activation-1 protein (BRAT1). We report a case of a female infant born to non-consanguineous Korean parents who developed hypertonia, dysmorphic features, progressive encephalopathy with refractory seizures at birth, and worsening intermittent apnea, leading to intubation and death at 137 days of age. The initial repeated electroencephalographic findings were normal; however, a pattern of focal seizures emerged at 35 days of life. Rapid trio whole-exome sequencing revealed heterozygous mutations c.1313_1314delAG p.(Gln438Argfs*51) and c.1276C>T p. (Gln426*) in BRAT1. After genetic counseling for pregnancy planning, a preimplantation genetic diagnosis for targeted BRAT1 mutations was successfully performed, and a healthy baby was born. To our knowledge, this is the first reported case of a Korean patient with compound heterozygous mutations in BRAT1. An early and accurate genetic diagnosis can help provide timely treatment to patients and indicate the need for reproductive counseling for parents for family planning

Angiogenesis effect of udenafil in a caveolin-1 deficient moyamoya disease model: A pre-clinical animal study

Purpose Although pathogenic mechanisms of moyamoya disease (MMD) remain unknown, recent studies suggest that it is a caveolae disease. This study evaluated the effect of udenafil, a phosphodiesterase-5 inhibitor, on angiogenesis in in vitro and in vivo MMD models. Methods Angiogenesis and vessel maturation were assessed in in vitro models, caveolin- 1 (Cav-1) knockdown human umbilical vessel endothelial cells (HUVECs) and coronary artery smooth muscle cells (CASMCs), and in in vivo model of bilateral internal carotid artery occlusion (bICAo). Udenafil was administered (1,3,10, and 30 μM) in cell culture conditions, and functional studies (migration and tube formation assay) were performed and vessel maturation factors and cyclic guanosine monophosphate (cGMP) accumulation were measured. Results Udenafil (3 and 10 mg/kg) was orally administered once daily for 4 weeks in bICAo rat model, and histological analysis for angiogenesis and vessel maturation was performed. Udenafil increased vessel formation in both Cav-1 knockdown HUVEC and bICAo models without increased migration/proliferation of HUVECs and CASMCs. Udenafil increased CD31+ vessel density and NG2/Col4+ mural cell density in bICAo models. Cav-1 knockdown inhibited accumulation of cGMP, and udenafil treatment restored cGMP levels in Cav-1 knockdown HUVEC models. Vessel maturation factors (angiopoietin- 1 and platelet-derived growth factor receptor-β) and angiogenic factors (endothelial nitric oxide synthase) were increased after treatment with udenafil in vitro. Conclusion Our results indicate that udenafil reversed cellular levels of cGMP related to Cav-1 deficiency and induced angiogenesis and vessel maturation. Further studies are warranted to confirm the therapeutic effects of this strategy in MMD

Homeobox gene Dlx-2 is implicated in metabolic stress-induced necrosis

<p>Abstract</p> <p>Background</p> <p>In contrast to tumor-suppressive apoptosis and autophagic cell death, necrosis promotes tumor progression by releasing the pro-inflammatory and tumor-promoting cytokine high mobility group box 1 (HMGB1), and its presence in tumor patients is associated with poor prognosis. Thus, necrosis has important clinical implications in tumor development; however, its molecular mechanism remains poorly understood.</p> <p>Results</p> <p>In the present study, we show that Distal-less 2 (Dlx-2), a homeobox gene of the Dlx family that is involved in embryonic development, is induced in cancer cell lines dependently of reactive oxygen species (ROS) in response to glucose deprivation (GD), one of the metabolic stresses occurring in solid tumors. Increased Dlx-2 expression was also detected in the inner regions, which experience metabolic stress, of human tumors and of a multicellular tumor spheroid, an <it>in vitro </it>model of solid tumors. Dlx-2 short hairpin RNA (shRNA) inhibited metabolic stress-induced increase in propidium iodide-positive cell population and HMGB1 and lactate dehydrogenase (LDH) release, indicating the important role(s) of Dlx-2 in metabolic stress-induced necrosis. Dlx-2 shRNA appeared to exert its anti-necrotic effects by preventing metabolic stress-induced increases in mitochondrial ROS, which are responsible for triggering necrosis.</p> <p>Conclusions</p> <p>These results suggest that Dlx-2 may be involved in tumor progression via the regulation of metabolic stress-induced necrosis.</p