Big Bandgap in Highly Reduced Graphene Oxides

It is generally believed that the bandgap of the graphene oxide is proportional to the concentration of the oxygen atoms and a highly reduced graphene oxide (rGO) without vacancy defects should be gapless. We show here from first principles calculations that the bandgap can be effectively opened even in low oxidation level with the absorption of oxygen atoms either symmetrically or asymmetrically. The properly arranged absorption can induce a bandgap up to 1.19 eV for a C/O ratio of 16/1 in a symmetric system and a bandgap up to 1.58 eV for a C/O ratio of 32/3 in an asymmetric system, at generalized gradient approximation (GGA) level. The hybridization between the in-plane p_<i>xy</i> orbitals of oxygen atoms and the out-of-plane p_<i>z</i> frontier orbital of graphene is responsible for the opening of the bandgap. This finding sheds new light on the bandgap engineering of graphene

Colletotrichine B, a new sesquiterpenoid from <i>Colletotrichum gloeosporioides</i> GT-7, a fungal endophyte of <i>Uncaria rhynchophylla</i>

<p>One new compound, colletotrichine B (<b>1</b>), was produced by the fungal <i>Colletotrichum gloeosporioides</i> GT-7. The structure of <b>1</b> was elucidated on the basis of spectroscopic analysis and X-ray crystallographic analysis. Monoamine oxidase (MAO), acetylcholinesterase (AChE) and phosphoinositide 3-kinase (PI3Kα) inhibitory activity of <b>1</b> was also evaluated. Compound <b>1</b> showed only AChE inhibiting activity with IC₅₀ value of 38.0 ± 2.67 μg/mL.</p

Table1_Evaluation of reference genes for quantitative expression analysis in Mylabris sibirica (Coleoptera, Meloidae).docx

Mylabris sibirica is a hypermetamorphic insect whose adults feed on oilseed rape. However, due to a shortage of effective and appropriate endogenous references, studies on molecular functional genes in Mylabris sibirica, have been tremendously limited. In this study, ten internal reference genes (ACT, ARF1, AK, EF1α, GAPDH, α-TUB, RPL6, RPL13, RPS3 and RPS18) were tested and assessed under four selected treatments including adult ages, adult tissues, temperatures, and sex by RT-qPCR based on five methods (Ct value, geNorm, NormFinder, BestKeeper and RefFinder). Our findings showed that RPL6 and RPL13 were the most optimal internal reference gene combination for gene expression during various adult ages and under diverse temperatures; The combination of RPL6 and RPS18 was recommended to test gene transcription levels under different adult tissues. AK and RPL6 were the best reference genes in male and female adults. RPL6 and RPL13 were the most appropriate reference gene pair to estimate gene expression levels under four different tested backgrounds. The relative transcript levels of a uridine diphosphate (UDP)-N-acetylglucosamine-pyrophosphorylase (MsUAP), varied greatly according to normalization with the two most- and least-suited reference genes. This study will lay the basis for further molecular physiology and biochemistry studies in M. sibirica, such as development, reproduction, sex differentiation, cold and heat resistance.</p

Efficient difluoromethylation of isoflavonoids and flavonoid under mild conditions

<p>A simple and efficient protocol for difluoromethylation of isoflavones, flavonoids, and coumarins has been developed. The protocol uses readily available, non-ozone-depleting and easy handling BrCF₂PO(OEt)₂ as difluorocarbene precursor. The reaction underwent the formation of difluorocarbene under mild reaction conditions with relatively weak base therefore demonstrates high selectivity. Application of the reaction led to difluoromethylated biologically relevant molecules.</p

YSO₄F·H₂O: A Deep-Ultraviolet Birefringent Rare-Earth Sulfate Fluoride with Enhanced Birefringence Induced by Fluorinated Y‑Centered Polyhedra

Birefringent crystals can modulate and detect the polarization of light and are important optical functional materials. The birefringence is positively correlated to the anisotropy of the structure. By partially substituting sulfate anion with large electronegative fluorine in the parent compound Y2(SO4)3·8H2O, a new fluorinated rare-earth sulfate YSO4F·H2O with enhanced anisotropy was achieved. YSO4F·H2O features a dense 3D structure constructed by the polarizable [YOF] polyhedra and [SO4] tetrahedra. The diffuse reflectance spectrum reveals that it has a short UV absorption edge of below 200 nm. The substitution of the F– ion enhances the optical anisotropy, making the material exhibit an enhanced birefringence (0.0357 at 546 nm), which is 5.1 times that of the parent compound and is also larger than most deep-UV birefringent sulfates. It is expected that this work may shed useful insights in the exploration of deep-UV birefringent materials with enhanced optical performances.

catch over

catch vWe go down every night,when we could cross the river. But sometimes you couldn't cross. The _ the lop'd break up th' ice, the wind would,but she'd catch over again. ( ie freeze over)freeze overYesDNE-cit J.D.A. WIDDOWSONJUL 1973Used I and SupUsed I and Sup1Used Icatch out, catching thirds, catch overChecked by Cathy Wiseman on Sat 18 Apr 201

Soil OM (g kg⁻¹) content as affected by main effects of P application and subplot effects of cropping system in 2011 and 2012.

<p>Values are means of three replicates. Values followed by the same lowercase letters are not significantly different among different cropping systems with the same P rate in one year at the 5% level by LSD (horizonal comparison); values followed by the same capital letters are not significantly different among different P rates (vertical comparison) or among different cropping systems (horizonal comparison) in one year at the 5% level by LSD. Values under ANOVA are the probabilities (<i>P</i> values) of the sources of variation.</p><p>Soil OM (g kg⁻¹) content as affected by main effects of P application and subplot effects of cropping system in 2011 and 2012.</p

Aboveground biomass and N, P and K acquisition of intercropping and weighted means of monocropped crops in 2011 and 2012.

<p>Different capital letters indicate significant differences at <i>P</i><0.05 by LSD among different P application rates; different lowercase letters with the same P application rates indicate significant differences at <i>P</i><0.05 by LSD among different cropping systems; F+M, S+M, C+M and T+M indicate intercropping of maize with faba bean, maize and soybean, and chickpea and turnip, respectively; M and I indicate monoculture and intercropping, respectively. The error bars are standard deviation with 3 replicates.</p

Conversion of Dinitrogen to Ammonia by FeN₃‑Embedded Graphene

Nitrogen fixation is one of the most important issues but a long-standing challenge in chemistry. Here, we propose FeN₃-embedded graphene as the catalyst for nitrogen fixation from first-principles calculations. Results show that in view of the chemical coordination, the FeN₃ center is highly spin-polarized with a localized magnetic moment substantially to promote N₂ adsorption and activate its inert N-N triple bond. The synergy between the graphene and FeN₃ equips the system with novel features for the catalytic conversion of the activated N₂ into NH₃ via a six-proton and six-electron process, following three possible reaction pathways at room temperature. Our findings provide a rational paradigm for catalytic nitrogen fixation that would be conducive to ammonia production

High ABCG4 Expression Is Associated with Poor Prognosis in Non-Small-Cell Lung Cancer Patients Treated with Cisplatin-Based Chemotherapy

<div><p>ATP-binding cassette (ABC) transporters are associated with poor response to chemotherapy, and confer a poor prognosis in various malignancies. However, the association between the expression of the ABC sub-family G member 4 (ABCG4) and prognosis in patients with non-small-cell lung cancer (NSCLC) remains unclear. NSCLC tissue samples (n = 140) and normal lung tissue samples (n = 90) were resected from patients with stage II to IV NSCLC between May 2004 and May 2009. ABCG4 mRNA and protein expressions were detected by RT-PCR, western blot, and immunohistochemistry. Patients received four cycles of cisplatin-based post-surgery chemotherapy and were followed up until May 31^st, 2014. ABCG4 positivity rate was higher in NSCLC than in normal lung tissues (48.6% <i>vs</i>. 0%, <i>P</i><0.001) and ABCG4 expression was significantly associated with poor differentiation, higher tumor node metastasis (TNM) stage, and adenocarcinoma histological type (all <i>P</i><0.001). Univariate (HR = 2.284, 95%CI: 1.570–3.324, <i>P</i><0.001) and multivariate (HR = 2.236, 95%CI: 1.505–3.321, <i>P</i><0.001) analyses showed that ABCG4 expression was an independent factor associated with a poor prognosis in NSCLC. Patients with ABCG4-positive NSCLC had shorter median survival than ABCG4-negative NSCLC (20.1 <i>vs</i>. 43.2 months, <i>P</i><0.001). The prognostic significance of ABCG4 expression was apparent in stages III and IV NSCLC. In conclusion, high ABCG4 expression was associated with a poor prognosis in patients with NSCLC treated with cisplatin-based chemotherapy.</p></div