Atomic-scale characterization of nitrogen-doped graphite: Effects of dopant nitrogen on the local electronic structure of the surrounding carbon atoms

We report the local atomic and electronic structure of a nitrogen-doped graphite surface by scanning tunnelling microscopy, scanning tunnelling spectroscopy, X-ray photoelectron spectroscopy, and first-principles calculations. The nitrogen-doped graphite was prepared by nitrogen ion bombardment followed by thermal annealing. Two types of nitrogen species were identified at the atomic level: pyridinic-N (N bonded to two C nearest neighbours) and graphitic-N (N bonded to three C nearest neighbours). Distinct electronic states of localized {\pi} states were found to appear in the occupied and unoccupied regions near the Fermi level at the carbon atoms around pyridinic-N and graphitic-N species, respectively. The origin of these states is discussed based on the experimental results and theoretical simulations.Comment: 6 Pages, with larger figure

Ionising irradiation-induced inhibition of differentiation of C3H10T1/2 cells to the osteoblastic lineage.

[Purpose]:Previous studies using mouse osteoblast derived MC3T3-E1 and mouse myoblast derived C2C12 cells have not completely explained the mechanisms responsible for osteoradionecrosis. Thus, the aim of this study was to advance the in vitro experimental approaches for investigations of osteoradionecrosis. [Materials and methods]:The pluripotent stem cell line, mouse embryo derived C3H10T1/2, was treated with all-trans-retinoic acid after irradiation (1, 3 and 6 Gy), and cell growth, cell cycle distribution, apoptosis, and alkaline phosphatase (ALP) activity were assessed. [Results]:We demonstrated that ionising radiation inhibited the growth and decreased ALP activity in C3H10T1/2 cells. The decrease in cell growth was not due to apoptosis but was due to cell cycle delay. The decrease in ALP activity persisted in cells that were induced to an osteoblastic lineage 24 h after irradiation. [Conclusions]:Our results suggested that C3H10T1/2 cells are suitable for investigating the effects of ionising irradiation on osteoblast precursor cells

Serotonin transporter gene polymorphism may be associated with functional dyspepsia in a Japanese population

<p>Abstract</p> <p>Background</p> <p>Although familial clustering of functional dyspepsia (FD) has been reported, the role of genetics in the susceptibility to FD is still not well understood. In the present study, the association between serotonin transporter (SERT) gene (<it>SLC6A4</it>) polymorphism and FD was explored.</p> <p>Methods</p> <p>Subjects were divided into either a postprandial distress syndrome (PDS) group or an epigastric pain syndrome (EPS) group according to the Rome III criteria. The healthy controls were those who had visited a hospital for an annual health check-up. The presence of the <it>SLC6A4 </it>promoter polymorphism, <it>5-hydroxytryptamin transporter gene linked polymorphic region </it>(<it>5-HTTLPR</it>), was then evaluated, and logistic regression analysis was used to test all variables.</p> <p>Results</p> <p>The <it>5-HTTLPR </it>genotype distribution was 448 SS, 174 SL, and 24 LL in controls and 30 SS, 20 SL, and 3 LL in FD subjects. No significant correlation was found between the <it>5-HTTLPR </it>genotype and FD. When the genotypes and subtypes of FD were exploratory evaluated, the SL genotype was significantly associated with PDS [odds ratio (OR) = 2.24, 95% confidence interval (CI); 1.16-4.32, <it>P </it>= 0.034 after Bonferroni correction] compared to the SS genotype adjusted for sex and age. Comparison of the SS genotype with the SL/LL genotype also showed a significant association of genotype with PDS (OR = 2.32, 95% CI; 1.23-4.37, <it>P </it>= 0.009).</p> <p>Conclusion</p> <p>The present results suggest that <it>5-HTTLPR </it>L allele may influence the susceptibility to PDS.</p

The exposure of field-grown maize seedlings to weed volatiles affects their growth and seed quality

Plants exposed to volatiles emitted from artificially damaged conspecific or heterospecific plants exhibit increased resistance to herbivorous insects. Here, we examined whether volatiles from artificially damaged weeds affect maize growth and reproduction. Seven days after germination, maize seedlings were exposed to volatiles emitted by artificially damaged mugwort (Artemisia indica var. maximowiczii) or tall goldenrod (Solidago altissima) plants either separately, or as a mixture of the two, for seven days. Unexposed seedlings were used as controls. Treated and control seedlings were cultivated in an experimental field without any insecticides applied. Plants exposed to either of the three volatile treatments sustained significantly less damage than controls. Additionally, seedlings exposed to either goldenrod or mixed volatiles produced more leaves and tillers than control plants. Furthermore, a significant increase in the number of ears was observed in plants exposed to the volatile mixture. In all treated plants, ear sugar content was significantly higher than that in the controls. Further, we cultivated seedlings that were either exposed to the volatile mixture or unexposed, under the conventional farming method using pesticides. Similar significant differences were observed for sugar content, number of tillers, leaves, damaged leaves, and ears. Laboratory experiments were conducted to further evaluate the mechanisms involved in the improved performance of volatile-treated plants. A significant reduction in the growth of common armyworm (Mythimna separata) larvae was observed when maize plants were exposed to the volatile mixture. This treatment did not affect the amount of jasmonic acid in the seedlings, whereas salicylic acid content increased upon exposure. The characteristic differences in chemical composition of mugwort and goldenrod volatiles were confirmed and, in turn, the volatile mixture differed significantly from the volatiles of either species

Copy Number Variations Due to Large Genomic Deletion in X-Linked Chronic Granulomatous Disease

Mutations in genes for any of the six subunits of NADPH oxidase cause chronic granulomatous disease (CGD), but almost 2/3 of CGD cases are caused by mutations in the X-linked CYBB gene, also known as NAD (P) H oxidase 2. Approximately 260 patients with CGD have been reported in Japan, of whom 92 were shown to have mutations of the CYBB gene and 16 to have chromosomal deletions. However, there has been very little detailed analysis of the range of the deletion or close understanding of the disease based on this. We therefore analyzed genomic rearrangements in X-linked CGD using array comparative genomic hybridization analysis, revealing the extent and the types of the deletion genes. The subjects were five Japanese X-linked CGD patients estimated to have large base deletions of 1 kb or more in the CYBB gene (four male patients, one female patient) and the mothers of four of those patients. The five Japanese patients were found to range from a patient exhibiting deletions only of the CYBB gene to a female patient exhibiting an extensive DNA deletion and the DMD and CGD phenotype manifested. Of the other three patients, two exhibited CYBB, XK, and DYNLT3 gene deletions. The remaining patient exhibited both a deletion encompassing DNA subsequent to the CYBB region following intron 2 and the DYNLT3 gene and a complex copy number variation involving the insertion of an inverted duplication of a region from the centromere side of DYNLT3 into the deleted region

Anti-reflection coating with mullite and Duroid for large-diameter cryogenic sapphire and alumina optics

We developed a broadband two-layer anti-reflection (AR) coating for use on a sapphire half-wave plate (HWP) and an alumina infrared (IR) filter for the cosmic microwave background (CMB) polarimetry. Measuring the faint CMB B-mode signals requires maximizing the number of photons reaching the detectors and minimizing spurious polarization due to reflection with an off-axis incident angle. Sapphire and alumina have high refractive indices of 3.1 and are highly reflective without an AR coating. This paper presents the design, fabrication, quality control, and measured performance of an AR coating using thermally-sprayed mullite and Duroid 5880LZ. This technology enables large optical elements with diameters of 600 mm. We also present a newly developed thermography-based nondestructive quality control technique, which is key to assuring good adhesion and preventing delamination when thermal cycling. We demonstrate the average reflectance of about 2.6% (0.9%) for two observing bands centered at 90/150 (220/280) GHz. At room temperature, the average transmittance of a 105 mm square test sample at 220/280 GHz is 83%, and it will increase to 90% at 100 K, attributed to reduced absorption losses. Therefore, our developed layering technique has proved effective for 220/280 GHz applications, particularly in addressing dielectric loss concerns. This AR coating technology has been deployed in the cryogenic HWP and IR filters of the Simons Array and the Simons observatory experiments and applies to future experiments such as CMB-S4

Carotid artery occlusion and colateral circulation in C57black/6J mice detected by synchrotron radiation microangiography

Using monochromatic synchrotron radiation, we performed microangiography inC57BL/6J mice and investigated their vasculature after unilateral and bilateral carotidartery occlusion. Bilateral occlusion of the carotid artery was made by a ligation of theleft common carotid artery followed by a ligation of the right internal carotid artery(ICA) two days later (n=12). Five days after the second surgery, angiography wasperformed. Unilateral occlusion was made by clipping the right ICA and thenangiography was performed immediately (n=5). The control mice did not undergo anyocclusion (n=5). We removed the brain of the bilateral occlusion mice afterangiography and examined the infarction area. The cerebral microvessels in all animalswere clearly visualized. In the control mice, the posterior communicating artery (Pcom)was not visualized. In the unilateral occlusion mice, the anastomosis of thepterygopalatine artery (PPA) and the external carotid artery (ECA) were recognized.The PPA is thus considered to play a role in the collateral vessel between the ICA andthe ECA. The Pcom was not visualized. In the bilateral occlusion mice, the Pcom wasobserved either unilateraly (n=5) or bilateraly (n=5). The Pcom supplied blood flow tothe anterior circulation from the vertebrobasilar arteries. The bilateral occlusion micethat had at least one visualized Pcom did not have any infarction. We could successfullyvisualize the cerebral vasculature of normal mice and carotid artery occluded mice inan in vivo study. Microangiography can demonstrate the development of vasculatureand the blood flow dynamics in mice

Contribution of visceral adiposity and insulin resistance to metabolic risk factors in Japanese men

金沢大学大学院医学系研究科北陸中央病院内科We investigated the relative impacts of visceral adiposity and insulin resistance on the metabolic risk profile in middle-aged Japanese men. A cross-sectional study was conducted in 636 nondiabetic Japanese men with a mean age of 51.6 years. Visceral adipose tissue (AT) was assessed using computed tomography, and insulin resistance was determined by the homeostasis model assessment of insulin resistance (HOMA-IR). Metabolic risk factors were diagnosed according to the National Cholesterol Education Program Adult Treatment Panel III metabolic syndrome criteria: (1) hypertriglyceridemia, (2) low high-density lipoprotein cholesterol, (3) hypertension, (4) impaired fasting glucose, and (5) impaired glucose tolerance. Visceral AT and HOMA-IR were significantly and positively correlated with each other (r = 0.41, P < .001). Using the 75th percentile value as a cut point, those with isolated large visceral AT showed significantly greater odds ratios for each of the 5 risk factors measured except impaired fasting glucose, whereas those with isolated high HOMA-IR showed significantly greater odds ratios for each of the 5 risk factors except hypertriglyceridemia and impaired glucose tolerance, compared with the control group. The combined group (increased visceral AT and HOMA-IR) had the highest odds ratios for all studied risk factors. On logistic regression analysis using visceral AT and HOMA-IR as continuous independent variables, they were each independently associated with most of the metabolic risk factors and their clustering. In conclusion, neither visceral AT nor HOMA-IR stands out as the sole driving force of the risk profile; each makes a significant contribution to metabolic abnormalities in Japanese men. © 2010 Elsevier Inc. All rights reserved

The G-Protein β3 subunit 825 TT genotype is associated with epigastric pain syndrome-like dyspepsia

<p>Abstract</p> <p>Background</p> <p>Although familial clustering of functional dyspepsia (FD) has been reported, the role of genetics in the susceptibility to FD is still not well understood. Several reports indicate an association between FD and G-protein β3 (GNB3) subunit gene polymorphism (C825T); however, these studies had small sample sizes and the findings are inconclusive. In the present study we clarified the association between GNB3 gene polymorphism and dyspepsia in a large population of Japanese subjects who visited a hospital for annual health check-up.</p> <p>Methods</p> <p>Subjects with significant upper gastrointestinal findings were excluded. Subjects with dyspeptic symptoms were divided into either a postprandial distress syndrome (PDS) group or an epigastric pain syndrome (EPS) group according to the Rome III criteria. The presence of the GNB3 C825T polymorphism was then evaluated and logistic regression analysis was used to test all variables.</p> <p>Results</p> <p>The GNB3 genotype distribution in subjects without dyspepsia was 191 CC (25.1%), 368 TC (48.4%), and 202 TT (26.5%) and 17 CC (25.0%), 29 TC (42.6%), and 22 TT (32.4%) in subjects with dyspepsia. No significant correlation was found between the GNB3 825TT genotype and dyspepsia. However, the TT genotype was significantly associated with subjects with EPS-like symptoms (odds ratio (OR) = 2.00, 95% confidence interval (CI); 1.07-3.76) compared to the CT/CC genotype adjusted for gender and age. No significant correlation was found between GNB3 polymorphism and PDS-like symptoms (OR = 0.68, 95% CI; 0.31-1.51). With the exclusion of subjects with both EPS- and PDS-like symptoms, only the TT genotype was significantly associated with EPS-like symptoms (OR = 2.73, 95% CI; 1.23-5.91).</p> <p>Conclusion</p> <p>The homozygous GNB3 825T allele influences the susceptibility to EPS-like dyspepsia.</p