bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of multicopper oxidase genes in the green rice leafhopper, Nephotettix cincticeps (Hemiptera: Cicadellidae), with focus on salivary gland‐specific genes
Authors: Matsumoto Yukiko , Hattori Makoto
Published: July 2019

Multicopper oxidase (MCO) enzymes are present ubiquitously and act on diverse substrates. Recently, the presence of multiple MCO genes has been described in many insects. Based on sialotranscriptome data, we identified and comprehensively characterized six MCO genes: NcLac1S, 1G, and 2–5 in the green rice leafhopper, Nephotettix cincticeps (Hemiptera: Cicadellidae). NcLac1S and NcLac1G belong to the MCO1 ortholog of other insects. NcLac2 forms a clade with MCO2s involved in the sclerotization and pigmentation of the cuticle. NcLac3 and NcLac4 form a clade with NlMCO3
–5 of the hemipteran Nilaparvata luges. NcLac5 forms a clade with MCORPs (MCO‐related proteins) that lack amino acid residues normally highly conserved in copper‐coordinated MCOs. NcLac1S and NcLac3 were specifically expressed in the salivary glands; whereas NcLac5 was primarily expressed in the salivary glands. Only NcLac3 protein is considered to have laccase activity in the salivary glands and salivary sheaths ejected by the insect. NcLac1G expression was relatively high in the testis. NcLac2 and NcLac4 were specifically expressed in the integument and in Malpighian tubules, respectively. Knockdown by RNA interference (RNAi) of either NcLac2 and NcLac5 in nymphs caused high mortality. All NcLac2‐knockdown nymphs showed depigmentation and soft cuticle, and eventually died, as did other MCO2‐knockdown insects. DsNcLac5‐injected nymphs (third, fourth, and fifth‐instar) showed high mortality, but injection into adults had no effect on survival or number of eggs deposited, suggesting that NcLac5 is not essential for survival after molting (eclosion). NcLac5 could be a promising target gene for control of N. cincticeps.
Design, synthesis, and evaluation of anticonvulsant activities of benzoxazole derivatives containing the 1,2,4‐triazolone moiety
Authors: Song Ming‐Xia , Huang Yuping , Wang Shiben , Wang Zeng‐Tao , Deng Xian‐Qing
Published: July 2019

A novel series of benzoxazole derivatives containing 1,2,4‐triazolone (5a‐m) was designed. These compounds were synthesized in order to screen their anticonvulsant activities by the maximal electroshock seizure (MES) model and the subcutaneous pentylenetetrazole (sc‐PTZ) seizure model in mice. The rotarod test was used to evaluate their neurotoxicities. Most of the compounds showed anti‐MES activities at 100 and 300 mg/kg. Compound5f, which showed potential anticonvulsant activity in the MES model with ED50values of 22.0 mg/kg, was considered as the most promising one in this study. It exhibited greater safety than that of carbamazepine and valproate regarding neurotoxicity. The efficacy of compound5fin inhibiting the tonic seizures and death induced by the convulsants 3‐mercaptopropionic acid and BIC was also verified. In an enzyme‐linked immunosorbent assay, compound5fand the positive drug phenytoin significantly increased the γ‐aminobutyric acid (GABA) level in the mouse brain. Further, pretreatment with an inhibitor of the GABA synthesizing enzyme dramatically raised the ED50value of5fin the MES model. These results confirmed that the compound5fplays its anticonvulsive action via regulating the GABA function in the brain. Also, a docking study of the compound5fin the benzodiazepine (BZD) binding site of the GABAAreceptor confirmed possible binding of the compound5fwith BZD receptors.
Understanding the role of Fischer–Tropsch reaction kinetics in techno‐economic analysis for co‐conversion of natural gas and biomass to liquid transportation fuels
Authors: Sahir Asad H. , Zhang Yanan , Tan Eric C. D. , Tao Ling
Published: July 2019

With the increased availability of low‐cost natural gas, the co‐conversion of natural gas and biomass‐to‐liquid fuels has attracted attention from industry due to its potential for improving liquid fuel yields while lowering greenhouse gas emissions. This study provides an understanding of Fischer–Tropsch kinetics, improvements in processing strategies for hydrocarbon production, and of its impact on cost for the co‐conversion of natural gas and biomass‐to‐transportation fuels. Studies that investigate the effect of Fischer–Tropsch reaction kinetics on techno‐economic analysis can be used to develop process models that consider reaction stoichiometry and account for the effect of the paraffin‐to‐olefin ratio. We consider two processing scenarios: (1) one that does not employ a hydrocracker, and (2) the other where a hydrocracker serves as an integral part of the process scheme. Our analysis shows that co‐processing natural gas not only facilitates the economic benefits of converting biomass‐to‐liquid fuels but also facilitates flexibility in process integration. The resulting minimum fuel selling price ranged from $2.47–$3.47/GGE (gallon gasoline equivalent) without the hydrocracker and ranged from $2.17–$3.60/GGE with the inclusion of the hydrocracker, for a 50 million GGE hydrocarbon fuel production facility and for varying blending ratios for biomass from 0–100% with natural gas. The hydrocracker helps to increase the production of diesel and jet fuels substantially, with carbon efficiencies of 50% attained for a chain growth probability of 0.87. The cost penalty comes from the capital expenses of the hydrocracker, and the expense may not be offset with hydrocarbon yield improvement. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.
Spectroscopic and computational exploration of hypoxanthine riboside interacting with plasma albumin
Authors: Zhang Hua‐xin , Zhou Dan , Xia Qing‐hua
Published: July 2019

Hypoxanthine riboside (HXR) is a nucleoside essential for wobble base pairs to translate the genetic code. In this work, an absorption and luminescence study showed that HXR and human serum albumin (HSA) formed a new complex through hydrogen bonds and van der Waals forces at ground state. Fluorescence probe experiments indicated that HXR entered the first subdomain of domain II in HSA and was fixed by amino acid residues in site I defined by Sudlow, and after competing with a known site marker. The recognition interaction featured negative ΔHϴ, ΔSϴ and ΔGϴ thermodynamic parameters. Fluorescence and circular dichroism spectra described the polarity of residues and α‐helix and β‐strand content changed because of HXR binding. The most rational structure for the HXR–HSA complex was recommended by the molecular docking method, in which the binding location, molecular orientation, adjacent amino acid residues, and hydrogen bonds were included. In addition, the influence of β‐cyclodextrin and some essential metal ions on the balance of the HSA–HXR system interaction was measured. The study gained comprehensive information on the transportation mechanism for HXR in blood, and was of great significance in understanding the theory of HXR biotransformation and in discussing its clinical in vivo half‐life.
The structure and luminescence properties of Mn2+/Eu2+/Er3+‐doped MgO‐Ga2O3‐SiO2 glasses and glass‐ceramics
Authors: Gao Zhenyu , Yu Lixin , Man Xiaoqin , Zhong Jianlin , Guo Qihuang , Zou Yingxuan
Published: July 2019

The MgO–Ga2O3–SiO2 glasses and glass‐ceramics samples doped with Eu2+/Mn2+/Er3+ and heated in reductive atmosphere were prepared by the sol–gel method. The structure, morphology and the luminescence properties were studied using X‐ray diffraction, high‐resolution transmission electron microscope, fluorescence spectra, and up‐conversion emission. The luminescence characteristics of doped ions could be influenced by temperature and matrix component. The characteristic emission of Mn2+, Eu2+ and Er3+ were seen and the energy transfer efficiency from Eu2+ to Mn2+ was enhanced as Mn2+ concentration was increased. In addition, the two‐photon process was determined for the Er3+‐doped samples.
The intellectual structure of the journal Business Strategy and the Environment: A 25‐year author cocitation analysis
Authors: Kabongo Jean D.
Published: July 2019

This article presents the intellectual structure and 25‐year author cocitation analysis of the journal Business Strategy and the Environment. The findings show that Business Strategy and the Environment is an emerging, well‐established journal in its field. The journal needs a core set of authors who are actively engaged in the production and certification of knowledge; further, it consists of a number of loosely linked research team contributors, each with its own areas of interest. The existence of these research teams is a sign of strength that characterizes the journal as it strives to foster a community of unified scholars whose published works advance our understanding of business strategic decisions and behavior with regard to the natural environment. This study is useful for contributors, readers, and editorial board members who form the journal's community of knowledge creation and certification.
Resection of the primary tumor improves survival in patients with gastro‐entero‐pancreatic neuroendocrine neoplasms with liver metastases: A SEER‐based analysis
Authors: Zheng Mengzhen , Li Yan , Li Tong , Zhang Lianfeng , Zhou Lin
Published: July 2019

Patients who suffer from gastro‐entero‐pancreatic neuroendocrine neoplasms (GEP‐NENs) often present with liver metastatic disease. The efficacy of primary tumor resection (PTR) for these patients remains controversial due to the relatively heterogeneous behavior of the primary tumor and the lack of clinical evidence. In this series, GEP‐NEN patients with liver metastases (LM) were selected from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. A logistic regression model was used to analyze variables that were associated with PTR. A Cox proportional hazards model was used to identify independent prognostic risk factors. In total, 1547 patients were enrolled in our study, including 897 patients who underwent PTR. Resection of the primary tumor was associated with prolonged survival in all patients (5‐year overall survival (OS) rates: 57.0% vs 15.4%, P < .001), and improved 5‐year OS rates were observed in patients with gastric, small intestinal, colorectal, and pancreatic subtypes (39.7%, 73.3%, 24.6%, and 59.7%, respectively). On the multivariate analysis, PTR was an independent prognostic factor of prolonged OS (HR = 0.48, 95% CI: 0.39‐0.59, P < .001). Patients with a young age (≤60 years), small intestinal or colorectal NENs, a large primary tumor, lymph node (LN) metastases, and high tumor differentiation were more likely to undergo PTR. However, patients with colorectal NENs or a large primary tumor (≥4 cm) were at an increased risk of death independently in the PTR subgroup. The risk factors for OS also included old age, gastric tumor location, and poor differentiation. In conclusion, although PTR prolonged OS in all GEP‐NEN patients presenting with LM, surgical recipients should be considered carefully. Age, primary tumor site, size, and differentiation might help surgeons identify patients who could benefit from PTR.
Phialomyces macrosporus: Chemical Constituents, Antimicrobial Activity and Complete NMR Assignments for the 7,7′‐Biphyscion
Authors: da Silva Brandão Mauricio , Silva Abreu Lucas , Geris Regina
Published: July 2019

Five known secondary metabolites, chrysophanol (1), 7,7′‐biphyscion (2), secalonic acid D (3), mannitol (4) and trehalose (5) were isolated for the first time from the extracts of the fungus Phialomyces macrosporus. Their structures were elucidated by NMR methods (1D and 2D NMR analysis), optical activity and ESI‐MS. Complete 1H and 13C assignments were performed for compound 2. The antimicrobial activity was evaluated by serial microdilution assay for compounds 2 and 3 and results showed that compound 3 exhibited a significant growth inhibition at concentrations of 15.6 mg/ml (S. aureus and S. choleraesius) and 0.97 mg/mL (B. subtilis), comparable to the positive control.
The vitamin D metabolome: An update on analysis and function
Authors: Jenkinson Carl
Published: July 2019

Current understanding of vitamin D tends to be focussed on the measurement of the major circulating form 25‐hydroxyvitamin D3 (25OHD3) and its conversion to the active hormonal form, 1α,25‐dihydroxyvitamin D3 (1α,25(OH)2D3) via the enzyme 25‐hydroxyvitamin D‐1α‐hydroxylase (CYP27B1). However, whilst these metabolites form the endocrine backbone of vitamin D physiology, it is important to recognise that there are other metabolic and catabolic pathways that are now recognised as being crucially important to vitamin D function. These pathways include C3‐epimerization, CYP24A1 hydroxylase, CYP11A1 alternative metabolism of vitamin D3, and phase II metabolism. Endogenous metabolites beyond 25OHD3 are usually present at low endogenous levels and may only be functional in specific target tissues rather than in the general circulation. However, the technologies available to measure these metabolites have also improved, so that measurement of alternative vitamin D metabolic pathways may become more routine in the near future. The aim of this review is to provide a comprehensive overview of the various pathways of vitamin D metabolism, as well as describe the analytical techniques currently available to measure these vitamin D metabolites.
MicroRNA‐214 suppresses cell proliferation and migration and cell metabolism by targeting PDK2 and PHF6 in hepatocellular carcinoma
Authors: Yu Qiangfeng , Zhou Jianyin , Jian Yizeng , Xiu Zhe , Xiang Leyang , Yang Dinghua , Zeng Wenlong
Published: July 2019

MiR‐214 has been reported to act as a tumor suppressor or oncogene involved in various malignancies. However, the biological functions and molecular mechanisms of miR‐214 in hepatocellular carcinoma (HCC) still remain unclear. Previous studies suggest that pyruvate dehydrogenase kinase 2 (PDK2) and plant homeodomain finger protein 6 (PHF6) may be involved in some tumor cell proliferation and migration. Therefore, we studied the relationship between PDK2/PHF6 and miR‐214. The expression of miR‐214, PDK2, and PHF6 was determined by quantitative real‐time polymerase chain reaction in HCC tissues and cell lines. The Luciferase reporter assay was used to confirm the interaction between miR‐214 and PDK2/PHF6. Cell proliferation, apoptosis, and migration were evaluated by cell counting kit‐8 assay, flow cytometry, and transwell assay, respectively. The expressions levels of α‐smooth muscle actin (α‐SMA) and E‐cadherin were detected via immunofluorescence assay. Here, we found that the expression of miR‐214 decreased in HCC and was negatively correlated with PDK2 and PHF6. Moreover, PDK2 and PHF6 were the direct targets of miR‐214 in HCC cells. Functional analysis showed that knockdown of PDK2 or PHF6 as well as miR‐214 overexpression significantly suppressed cell proliferation and migration in HCC cells. Furthermore, we found that the suppression of cell proliferation and migration through PDK2 or PHF6 knockdown could be partially reversed by miR‐214 down‐regulation. Moreover, we demonstrated a decrease of mesenchymal cell marker α‐SMA and increase of the epithelial marker E‐cadherin after miR‐214 overexpression, PDK2 knockdown or PHF6 knockdown, respectively, which also suggested that cell proliferation and migration were suppressed. Additionally, lactate and pyruvic acid production experiments confirmed miR‐214 could suppress the HCC cell lactate and pyruvic acid levels by down‐regulating PDK2/PHF6. In conclusion, MiR‐214 may act as a tumor suppressor gene, presenting its suppressive role in cell proliferation and migration of HCC cells by targeting PDK2 and PHF6, and might provide a potential therapy target for patients with HCC.
Chemical Doped Ternary and Quaternary Transition‐Metal‐Based Electrocatalysts for Hydrogen Evolution Reaction
Authors: Li Jiayuan , Zhang Mingkai , Zang Hang , Yu Baozhi , Ma Yuanyuan , Qu Yongquan
Published: July 2019

Electrocatalytic hydrogen evolution reaction (HER) through transition‐metal‐based (TMB) catalysts represents a totally sustainable and cost‐effective technology for practical hydrogen (H2) production with high purity. Unfortunately, most of the catalysts have the unsuitable hydrogen adsorption behavior and thereby insufficient H2 generation efficiency. The general strategy to address the problem is to introduce various cation or/and anion dopants for designing multivariate TMB catalysts, which comes down to the optimized electronic structures and thus hydrogen adsorption of surface active sites. In this minireview, we summarize the recent significant advances in multivariate TMB catalysts for HER, especially highlighting the contributions of various dopants as the modulator for the host materials. Finally, the remaining challenges and future perspectives on multivariate TMB catalysts for HER are also discussed.
Chemical Synthesis of Oligoribonucleotide (ASL of tRNALysT. brucei) Containing a Recently Discovered Cyclic Form of 2‐Methylthio‐N6‐threonylcarbamoyladenosine (ms2ct6A)
Authors: Debiec Katarzyna , Matuszewski Michal , Podskoczyj Karolina , Leszczynska Grazyna , Sochacka Elzbieta
Published: July 2019

The synthesis of the protected form of 2‐methylthio‐N6‐threonylcarbamoyl adenosine (ms2t6A) was developed starting from adenosine or guanosine by using the optimized carbamate method and, for the first time, an isocyanate route. The hypermodified nucleoside was subsequently transformed into the protected ms2t6A‐phosphoramidite monomer and used in a large‐scale synthesis of the precursor 17nt ms2t6A‐oligonucleotide (the anticodon stem and loop fragment of tRNALys from T. brucei). Finally, stereochemically secure ms2t6A→ms2ct6A cyclization at the oligonucleotide level efficiently afforded a tRNA fragment bearing the ms2ct6A unit. The applied post‐synthetic approach provides two sequentially homologous ms2t6A‐ and ms2ct6A‐oligonucleotides that are suitable for further comparative structure–activity relationship studies.
Hierarchy in the Halogen Activation During Surface‐Promoted Ullmann Coupling
Authors: Merino‐Díez Néstor , Pérez Paz Alejandro , Li Jingcheng , Vilas‐Varela Manuel , Lawrence James , Mohammed Mohammed S. G. , Berdonces‐Layunta Alejandro , Barragán Ana , Pascual Jose Ignacio , Lobo‐Checa Jorge , Peña Diego , de Oteyza Dimas G.
Published: July 2019

Within the collection of surface‐supported reactions currently accessible for the production of extended molecular nanostructures under ultra‐high vacuum, Ullmann coupling has been the most successful in the controlled formation of covalent single C−C bonds. Particularly advanced control of this synthetic tool has been obtained by means of hierarchical reactivity, commonly achieved by the use of different halogen atoms that consequently display distinct activation temperatures. Here we report on the site‐selective reactivity of certain carbon‐halogen bonds. We use precursor molecules halogenated with bromine atoms at two non‐equivalent carbon atoms and found that the Ullmann coupling occurs on Au(111) with a remarkable predilection for one of the positions. Experimental evidence is provided by means of scanning tunneling microscopy and core level photoemission spectroscopy, and a rationalized understanding of the observed preference is obtained from density functional theory calculations.
Reaction Dynamics in Extreme Environments and Astrochemistry
Authors: Kaiser Ralf I.
Published: July 2019

Ralf I. Kaiser
is Professor of Physical Chemistry at the Department of Chemistry and Director of the W.M. Keck Laboratory in Astrochemistry, Department of Chemistry, University of Hawaii at Manoa (USA). He is a current member of the ChemPhysChem Editorial Board.
A Cobalt‐Modified Covalent Triazine‐Based Framework as an Efficient Cocatalyst for Visible‐Light‐Driven Photocatalytic CO2 Reduction
Authors: Bi Jinhong , Xu Bin , Sun Long , Huang Huimin , Fang Shengqiong , Li Liuyi , Wu Ling
Published: July 2019

Photocatalytic CO2 reduction into carbonaceous feedstock chemicals is a promising renewable energy technology to convert solar energy and greenhouse gases into chemical fuels. Here, a covalent triazine‐based framework (CTF) is demonstrated as an efficient cocatalyst to reduce CO2 under visible‐light irradiation. The nitrogen‐rich triazine moieties in CTF contribute to CO2 adsorption, while the periodical pore structure of CTF favors the accommodation of CO2 and electron mediator. Immobilization of cobalt species onto CTF promotes the photocatalytic activity with a 44‐fold enhancement over pristine CTF and the optimal CO production rate of the obtained Co/CTFs was up to 50 μmol g−1 h−1. The results of solid‐state UV‐vis diffuse reflectance spectra (UV‐vis DRS), CO2 adsorption and electrochemical impedance spectroscopy (EIS) illustrated that the increased activity was ascribed to the enhanced CO2 capture capacity, improved absorption of visible‐light and facilitated the transfer of charge from CTF to CO2 molecules. The CTF not only serves as a substrate for active Co species, but also bridges the photosensitizer with cobalt catalytic sites for the efficient transfer of photoexcited electrons. This work highlights the capability and ease of fabricating covalent organic framework‐based photocatalytic systems that are potentially useful for energy‐conversion applications.
Helical Self‐Assembly of Optically Active Glycoconjugated Phthalocyanine J‐Aggregates
Authors: Bächle Felix , Maichle‐Mössmer Cäcilia , Ziegler Thomas
Published: July 2019

Four galactoconjugated zinc(II) phthalocyanines (Pcs) have been prepared and fully characterized. The carbohydrate‐containing phthalonitrile precursors of the Pcs were synthesized through a copper‐catalysed azide‐alkyne cycloaddition (CuAAC). The Pcs show a remarkable aggregation behaviour in solution, depending on the nature of the solvent, the temperature and the substitution position on the phthalocyanine. Solvent‐dependent CD‐spectroscopy experiments show that these Pcs aggregate as chiral helices in solution. Crystal structure data of a phthalocyanine bearing two carbohydrate units substantiate the properties shown by CD spectroscopy. Furthermore, the 1,2,3‐triazole moieties of the Pcs play a decisive role in the formation of supramolecular aggregates. The glycoconjugated zinc(II) phthalocyanines described here show molar extinction coefficients ϵmax>105 M−1 cm−1 and absorption maxima λmax>680 nm, which make them attractive photosensitizers for Photodynamic Therapy (PDT).
3D Anisotropic Stress Analysis during Kyropoulos Growth of Sapphire Single Crystal
Authors: Zermout S. , Mokhtari F. , Nehari A. , Lasloudji I. , Haddad F. , Merah A.
Published: July 2019

By using 3D finite element calculations, numerical simulations are performed to predict the thermal field as well as the thermal stress in a c‐axis sapphire single crystal grown by Kyropoulos technique. The effects of additional resistive heating (placed under the crucible bottom) and crystal rotation are investigated and a comparison is made between the isotropic and anisotropic analysis. The anisotropy of the elastic constants and thermal expansion coefficients as well as their temperature dependence are considered in the anisotropy calculations while Young's modulus and the Poisson ratio are used in the isotropic analysis. Thermal stress is found to be smaller in the anisotropy analysis than that in the isotropic analysis and significant differences are found in their respective distribution patterns. Additional resistive heating acts to decrease both of the crystal–melt interface convexity and the von Mises stress. In addition, crystal rotation combined with additional resistive heating decreases significantly the thermal stress inside the sapphire crystal and along the melt–crystal interface. Therefore, optimizing the heating conditions and using a suitable crystal rotation rate seem to be favorable to control the growth interface shape and to reduce thermal‐stress‐related defects during the growth process.
Phytoplankton community responses to temperature fluctuations under different nutrient concentrations and stoichiometry
Authors: Gerhard Miriam , Koussoroplis Apostolos Manuel , Hillebrand Helmut , Striebel Maren
Published: July 2019

Nutrient availability and temperature are important drivers of phytoplankton growth and stoichiometry. However, the interactive effects of nutrients and temperature on phytoplankton have been analyzed mostly by addressing changes in average temperature, whereas recent evidence suggests an important role of temperature fluctuations. In a laboratory experiment, we grew a natural phytoplankton community under fluctuating and constant temperature regimes across 25 combinations of nitrogen (N) and phosphorus (P) supply. Temperature fluctuations decreased phytoplankton growth rate (rmax), as predicted by nonlinear averaging along the temperature–growth relationship. rmax increased with increasing P supply, and a significant temperature × P × N interaction reflected that the shape of the thermal reaction norm depended on nutrients. By contrast, phytoplankton carrying capacity increased with N supply and in fluctuating rather than constant temperature. Higher phytoplankton N:P ratios under constant temperature showed that temperature regimes affected cellular nutrient incorporation. Minor differences in species diversity and composition existed. Our results suggest that temperature variability interacts with nutrient supply to affect phytoplankton physiology and stoichiometry at the community level.
Effect of soil heterogeneity and endogenous processes on plant spatial structure
Authors: Schouten Olivia S. , Houseman Gregory R.
Published: July 2019

Within communities, organisms potentially self‐organize through endogenous processes that create nonrandom spatial structure as they interact with one another or modify the abiotic environment. In contrast, exogenous processes such as environmental heterogeneity or variable immigration are thought to be dominant processes controlling these spatial patterns. Although both endogenous and exogenous processes likely occur, their relative importance is still largely unknown because of limited analytical tools and the lack of experimental evidence, particularly those that address exogenous sources of environmental heterogeneity. Here, we used a soil heterogeneity experiment to examine the relative effect of endogenous and exogenous processes on plant spatial structure after five years of community assembly. Soil heterogeneity was manipulated by splitting the vertical soil profile into three soil‐types that were randomly assigned to 40 × 40 cm patches within 2.4 × 2.4 m plots. Homogeneous plots were created by mixing all soils before filling each patch. Thirty‐four grassland species were then sown into all plots and allowed to grow for five years after which the location of all plants was mapped using a 5 × 5 cm grid. Results from point‐pattern spatial analysis indicated that, even in the absence of soil heterogeneity and with initial seed arrival, spatial structure was primarily generated by endogenous processes. Although soil heterogeneity increased species aggregation at certain scales, most of the spatial structure was created by endogenous processes. These results suggest that endogenous processes may be more important than expected for generating spatial structure and can develop much faster than anticipated.
Re‐evaluating pattern and process to understand resilience in transitional mixed conifer forests
Authors: Meunier Jed , Holoubek Nathan S. , Brown Peter M. , Sebasky Megan
Published: July 2019

A key challenge to maintaining resilient landscapes is adapting to and maintaining dynamic ecological processes. In fire‐dependent ecosystems, this includes identifying and defining mechanisms through which fire influences forest structure and functionality. Interpretations of tree patterns via land survey records in the Lake States have often highlighted the importance of infrequent moderate to extreme disturbance events. However, historical survey methods are limited to observing higher severity disturbances and over large landscapes, thus it is not clear if the origin, structure, and forcing factors for either patterns or processes are adequately quantified by these methods. We used dendrochronological methods to determine how fire history and stand structure, including cohort structure, tree density, and spatial patterning, are linked within Lake States mixed conifer forests in Wisconsin. We found relatively short mean fire return intervals (MFRIs) ranging from 6 to 13 yr with little variation in fire frequency among sites. Current densities of red‐pine‐dominated forests are 4–37 times historical (ca. 1860) densities (mean 12×) and almost entirely spatially random, whereas historically forests were spatially aggregated at stand scales. Stands also contained multiple and/or loosely defined cohort structures suggesting very different controls operating historically than currently. Heterogeneity that helped maintain ecosystem resilience in these ecosystems historically came from frequent fire disturbance processes that affected stand‐scale forest resistance. This was likely the historical dynamic across fire‐adapted transitional pine forests of the Lake States.
Influence of Hetero‐Biaryl Ligands on the Photo‐Electrochemical Properties of [ReINCS(N∩N)(CO)3]‐Type Photosensitizers
Authors: Mosberger Mathias , Probst Benjamin , Spingler Bernhard , Alberto Roger
Published: July 2019

A complete set of the symmetrical bidiazine (bdz) and asymmetrical pyridyldiazine (pydz) ligands, along with the known 2,2′‐bipyridyl (bpy) ligand, and their respective rhenium(I)‐tricarbonyl‐bromo and ‐thiocyonato complexes are presented. A bathochromic shift is observed with an increasing number of nitrogen atoms, caused by a stabilization of the diimine based LUMO. As expected from the energy gap law, this results in an increase in the non‐radiative decay constant (knr) along the line bpy‐pydz‐bdz. Interestingly, the increase in knr for both pyridazine ligands (2‐(pyridin‐2‐yl)pyridazine (pypdz) and 3,3′‐bipyridazine (bpdz)) is much less pronounced as compared to the other pydz resp. bdz ligands. This results in overall longer lifetime and quantum yield, at the increased spectral overlap with sunlight – both properties sought for in the creation of light‐harvesting schemes in photochemistry.
Stripped Charge of Ag Less than Deposited one Owing to Negative Capacitance Caused by Redox Reactions
Authors: Aoki Koichi Jeremiah , Chen Jingyuan , Wang Ru
Published: July 2019

Anodic stripping voltammetry was made in AgNO3 solution, here Ag was deposited under long term potentiostatic conditions to evaluate the reduction charge, qr, and then was stripped by linear sweep voltammetry to determine the oxidation charge, qo. The charges were unbalanced, satisfying ca. qo=0.7|qr|, where other possible reduction charge such as by dioxygen and dichlorosilver were subtracted. The 30 % loss of the anodic charge can be ascribed to the negative capacitance by the potential sweep generation of Ag+. The generated Ag+ forms a dipole with a counter ion, of which orientation is the same as the direction of the externally applied electric field and opposite to the dipoles of solvent. The redox dipole decreases the conventional double layer capacitance caused by solvent dipoles, and high concentrations of Ag+ takes the capacitance to be negative values. The unbalanced charge, however, has no influence on quantitative determination of concentrations Ag+ by use of a calibration line.
First Electroanalytical Methodology for the Determination of Hordenine in Dietary Supplements using a Boron‐doped Diamond Electrode
Authors: Allahverdiyeva Shabnam , Keskin Ertuğrul , Pınar Pınar Talay , Yardım Yavuz , Şentürk Zühre
Published: July 2019

The present work describes the first electrochemical investigation and a simple, rapid and modification‐free electroanalytical methodology for quantification of hordenine (a potent phenylethylamine alkaloid) using a boron‐doped diamond electrode. At optimized square‐wave voltammetric parameters, the observed oxidation peak current in 0.1 M HClO4 at +1.33 V (vs. Ag/AgCl) increased linearly from 5.0 to 100 μg mL−1 (3.0×10−5–6.1×10−4 M), with detection limit of 1.3 μg mL−1 (7.8×10−6 M). The applicability of the developed method was tested with the determination of hordenine in the commercial dietary supplement formulations.
Computational investigation of flame extension height for horizontally oriented rectangular source jet fires impinging on a vertical plate
Authors: Huang Youbo , Li Yanfeng , Dong Bingyan , Li Junmei
Published: July 2019

This paper investigates the flame extension height induced by a horizontally oriented rectangular source fire impinging on a vertical plate, which has rarely been reported in literature. Focusing on the scenarios with nonimpinging flame lengths that are comparable with or larger than the plate‐source distance, a series of numerical experiments were conducted, in which the exit velocities varied from 27.5 to 125 m/s and the orifice aspect ratios ranged from 1 to 4. Results show that the flame extension height increases with increasing exit velocity and becomes larger with increasing orifice aspect ratio at a given fuel exit velocity. New correlations are proposed to predict the flame extension height based on the unburnt fuel after impinging, assuming a kite flame shape of circular and elliptical cross section. Moreover, the new proposed correlations provide a general and practical basis for estimating the flame extension height of horizontally oriented rectangular source impinging jet fires.
Hallmarks of cancer: Tumor budding as a sign of invasion and metastasis in head and neck cancer
Authors: Mäkitie Antti A. , Almangush Alhadi , Rodrigo Juan P. , Ferlito Alfio , Leivo Ilmo
Published: July 2019

Invasion and metastasis are hallmarks of cancer. The concept of tumor budding at tumor‐host interface has been documented in many carcinomas. A growing body of evidence indicates that tumor budding is a sign of invasion and early step for metastasis of many epithelial cancers including head and neck squamous cell carcinoma (HNSCC). In addition, recent research has underlined the importance of tumor budding as a promising prognosticator in HNSCC. This review summarizes the findings regarding tumor budding in HNSCC and focuses on the role of tumor budding in invasion and metastasis. Also, we highlight the prognostic significance of tumor budding in HNSCC and its potential for improving clinical decision making in terms of recommending optimal individualized treatment for this patient population.
Very late xerostomia, dysphagia, and neck fibrosis after head and neck radiotherapy
Authors: Baudelet Margot , Van den Steen Leen , Tomassen Peter , Bonte Katrien , Deron Philippe , Huvenne Wouter , Rottey Sylvie , De Neve Wilfried , Sundahl Nora , Van Nuffelen Gwen , Duprez Fréderic
Published: July 2019

Background

Acute and late toxicity after intensity‐modulated radiotherapy (IMRT) for head and neck cancer (HNC) impacts on patient quality of life; yet, very late toxicity data remain scarce. This study assessed dysphagia, xerostomia, and neck fibrosis 3‐8 years after IMRT.

Methods

A retrospective analysis using generalized estimated equations was performed on 60 patients with HNC treated with fractionated IMRT between 2000 and 2015 who had a follow‐up ≥8 years. Toxicity was scored using LENT‐SOMA scales.

Results

A trend towards a nonlinear global time effect (P= .05) was noted for dysphagia with a decrease during the 5 years post‐treatment and an increase thereafter. A significant decrease in xerostomia (P= .001) and an increase in neck fibrosis (P= .04) was observed until 8 years.

Conclusions

Dysphagia, xerostomia, and neck fibrosis do not appear stable over time and remain highly prevalent in the very late follow‐up. Our findings support the need for prospective trials investigating very late toxicity in patients with HNC.
Photo‐assisted electrochemical hydrogen evolution by plasmonic Ag nanoparticle/nanorod heterogeneity
Authors: Wu Hao , Alshareef Husam N. , Zhu Ting
Published: July 2019

Transition metal sulfide‐based hydrogen evolution electrocatalysts still lag in catalytic activity due to the zero‐deviated free energy of *H adsorption. Plasmonic metals bridge the gap between light utilization and plasmon‐mediated redox reactions for substantially enhanced electrocatalytic activity. In this work, a strategic broadband light utilization heterostructure, composed of two distinct Ag nanostructures (discontinuous Ag nanorods and monodispersed nanoparticles), is achieved through in situ sulfurization and metal leaching. The heterostructure benefits the electrocatalytic hydrogen evolution reactivity thanks to the localized surface plasmon resonance induced hot electrons injection and inter‐gap electric fields revealed by the finite‐difference time‐domain simulation. Experimentally, the prudent heterostructured catalyst exhibits a significantly improved overpotential (at 10 mA cm−2) from 151 to 95 mV along with a Tafel slope from 74 to 45 mV dec−1 toward hydrogen evolution. Significantly, this instructional study sheds light on the design of hybrid photo‐assisted electrocatalysts with cooperative effect of solar energy toward sustainable electrocatalysis.
LncRNA RMST activates TAK1‐mediated NF‐κB signaling and promotes activation of microglial cells via competitively binding with hnRNPK
Authors: Sun Xiu‐Lan , Wang Zhao‐Lu , Wu Qian , Jin Shan‐Quan , Yao Juan , Cheng Hong
Published: July 2019

This study aimed to explore the biological role and molecular mechanism of long noncoding RNA (lncRNA) rhabdomyosarcoma 2‐associated transcript (RMST) in regulating microglial activation. Mouse microglial BV2 cells were cultured to establish the cell model of cerebral ischemic stroke by oxygen–glucose deprivation (OGD). We observed highly expressed RMST, increased expression of M1, and decreased expression of M2 markers in BV2 microglial cells stimulated with OGD. These alterations were reversed by RMST knockdown. Activation of transforming growth factor‐beta‐activated kinase 1 (TAK1)‐mediated nuclear factor‐κB (NF‐κB) pathway was observed upon OGD stimulation, which was promoted by RMST through competitively binding with heterogeneous nuclear ribonucleoprotein K (hnRNPK), confirmed by RNA pull down and RNA immunoprecipitation (RIP) assays. Furthermore, RMST overexpressing‐BV2 cells effectively enhanced neuronal apoptosis. In conclusion, RMST promoted OGD‐induced microglial M1 polarization by competitively interacting with hnRNPK via TAK1‐mediated NF‐κB pathway, which will provide a basis for understanding the pathogenesis of cerebrovascular diseases.
Nano‐LC based proteomic approach identifies that E6AP interacts with ENO1 and targets it for degradation in breast cancer cells
Authors: Mishra Mukul , Sharma Akshay , Thacker Gatha , Trivedi Arun K.
Published: July 2019

E6AP (E6 associated protein) is a HECT domain containing protein having dual E3 ligase and ERα coactivation activity in breast cancer cells. Although E6AP is known to possess antitumorigenic activity, the underlying molecular mechanism is poorly understood. In the present study, we applied nano‐LC based proteomics approach to identify E6AP‐interacting proteins where we performed GST‐pull down using GST‐E6AP from whole cell extracts of MCF7 cells, resolved the differentially interacting proteins on 1D‐SDS‐PAGE, excised the gel bands that were trypsin digested followed by fractionation and spotting on MALDI‐TOF/TOF plate through Nano‐LC MALDI spotter. Subsequently, fractionated and spotted peptides were identified using MALDI‐TOF/TOF. We identified several E6AP interacting proteins including previously reported such as HSP70 and new ones such as Enolase‐1. We further confirmed that E6AP and Enolase1 interacted and colocalized more in the cytoplasmic periphery in breast cancer cells and further demonstrated that E6AP also targeted ENO1 for ubiquitin‐mediated degradation in these cells.
An analysis of the value of token reinforcement using a multiple‐schedule assessment
Authors: Fiske Kate E. , Isenhower Robert W. , Bamond Meredith J. , Lauderdale‐Littin Stacy
Published: July 2019

Token systems are widely used in clinical settings, necessitating the development of methods to evaluate the reinforcing value of these systems. In the current paper, we replicated the use of a multiple‐schedule reinforcer assessment (MSA; Smaby, MacDonald, Ahearn, & Dube, 2007) to evaluate the components of a token economy system for 4 learners with autism. Token systems had reinforcing value similar to primary reinforcers for 2 of the 4 learners, but resulted in lower rates of responding than primary reinforcers for the other 2 learners. Differentiated responding across learners may warrant variation in clinical recommendations on the use of tokens. The results of this study support formal assessment of token system effectiveness, and the MSA procedure provides an efficient method by which to conduct such assessments.
Nickel oxide nanoparticles exert selective toxicity on skin mitochondria and lysosomes isolated from the mouse model of melanoma
Authors: Rahimi Shabnam , Naserzadeh Parvaneh , Mousavi Zahra , Ashtari Khadijeh , Seydi Enayatollah , Pourahmad Jalal
Published: July 2019

Nickel oxide nanoparticles (NiO‐NPs) are progressively used for an immense number of new applications in modern industries sectors. Nevertheless, the toxic impact of NiO‐NPs has not been clearly elucidated on human melanoma cell lines at the cellular and molecular level. Hence, this study was designed to examine the in vitro cytotoxicity potentials of NiO‐NPs on malignant cutaneous melanoma (MCM) mitochondria. Results revealed that NiO‐NPs significantly increased reactive oxygen species level, lipid peroxidation, and mitochondrial membrane potential and decreased succinate dehydrogenase activity, glutathione level, and ATP content on skin mitochondria isolated from the mouse model of melanoma compared with the non‐cancerous mouse skin mitochondria. Our results revealed that NiO‐NPs induced lysosomal membrane labialization on mentioned mitochondria. The current study showed that NiO‐NPs could significantly induce selective cytotoxicity on MCM mitochondria. Therefore, this compound may be considered as a promising candidate for further in vivo and clinical studies to reach a new anti‐MCM drug.
Analysis of the atomic force microscopy vibration behavior using the Timoshenko theory by multi‐scale method in the air environment
Authors: Korayem A. H. , Imani F. , Korayem Moharram H.
Published: July 2019

This article deals with the modeling and simulation of the vibration behavior of piezoelectric micro‐cantilever (MC) based on the Timoshenko theory and using multi‐scale (MTS) method in the air environment. In this regard, the results are compared with the previous literature, such as the finite element method and the MTS method. The analysis of the piezoelectric MC vibrating behavior is investigated in a dynamical mode including non‐contact and tapping modes. The dynamics of this system is affected by interferential forces between probe tip and sample surface, such as van der Waals, capillary, and contact forces. According to the results, the forces applied to the probe tip reduce the amplitude and the resonance frequency. The simulation of surface topography in non‐contact mode and tapping for rectangular and wedge‐shaped roughness in the air environment are presented. Various experiments have been conducted in Ara research Company using the atomic force microscopy device in the amplitude mode. In the NSC15 Cantilever, the first natural frequency is derived from the results of the MC simulation based on Timoshenko beam theory, the practical results are 295.85 and 296.12 kHz, and the error rate is 0.09; at higher natural frequencies, the error rate has been increased. The
γ
f coefficient is a measure of the nonlinear effects on the system; the effect of the piezoelectric length and width on
γ
f coefficient is also investigated.
Laparoscopic cholecystectomy for cholecystolithiasis with Dubin–Johnson syndrome
Authors: Wang Baolin , Yang Shouda , Hu Xiaoming , Zhang Yongfeng
Published: July 2019

Dubin–Johnson syndrome is a rare, autosomal recessive hereditary disease, commonly known as “black liver disease.” It is of great interest for surgeons to accidentally find the “black liver” during laparoscopic cholecystectomy (LC). We performed an emergency LC for cholecystolithiasis with Dubin–Johnson syndrome in 2013. We only performed cholecystectomy and liver tissue biopsy. Following a 5‐year follow‐up period, the patient does not appear to have abdominal pain and any other discomfort. Dubin–Johnson syndrome has no significant relationship with the occurrence of cholecystolithiasis and generally requires no special treatment. It is necessary to avoid misdiagnosis and overtreatment in the clinic.
Methylenetetrahydrofolate reductase polymorphisms and colorectal cancer prognosis: A meta‐analysis
Authors: Chen Xin‐Lin , Wang Yu‐Mei , Zhao Fei , Chen Zheng , Yang Xiaofei , Sun Cong , Gao Yunpeng , Yang Tian‐Ge , Tian Guo , Chen Yi‐Ming , Zhu Shui‐Lian , Lin Xiao‐Bing , Liu Feng‐Bin
Published: July 2019

Background

The present study focused on understanding the prognostic value of the methylenetetrahydrofolate reductase (MTHFR) single nucleotide polymorphisms rs1801133 (C667T) and rs1801131 (A1298C) in patients with colorectal cancer (CRC).

Methods

A systematic literature search was conducted in March 2016. Databases, including Medline, EMBASE, Cochrane and Chinese databases (including CNKI, Wanfang and VIP), were searched to identify the relevant articles describing MTHFR polymorphisms in patients with CRC. Data regarding overall survival (OS), progression‐free survival (PFS) and disease‐free survival (DFS) were collected and analysed.

Results

Twenty‐four studies with 5423 patients with CRC were included. Significant differences in OS, PFS and DFS were not observed among the different comparisons of patients carrying different alleles of the MTHFR rs1801133 polymorphism (including TT versus CC, TT versus CT + CC, CT + TT versus CC and CT versus CC). Compared with patients with the rs1801131 CA + AA genotypes, patients with the CC genotype had a shorter OS (hazard ratio = 1.85; 95% confidence interval = 1.30–2.65) and DFS (hazard ratio = 2.16; 95% confidence interval= 1.19–3.93). Significant differences in OS, PFS and DFS were not observed among the other patient groups (including CC versus AA, CC + CA versus AA and CA versus AA). Subgroup analysis of rs1801133 and rs1801131 showed that patients with CRC from Asian regions and Western regions demonstrated similar results.

Conclusions

The MTHFR rs1801133 polymorphism was not associated with the prognosis of patients with CRC; however, rs1801131 may be associated with the prognosis of patients with CRC. Well‐designed prospective studies are necessary to obtain a better understanding of the prognostic value of rs1801133 and rs1801131.