bluuebunny/crossref_metadata_2025 huggingface dataset:
Boron(II) Cations: Interplay between Lewis‐Pair‐Acceptor and Electron‐Donor Properties
Authors: Widera Anna , Vogler Daniel , Wadepohl Hubert , Kaifer Elisabeth , Himmel Hans‐Jörg
Published: July 2018

Boron(III) cations are widely used as highly Lewis acidic reagents in synthetic chemistry. In contrast, boron(II) cations are extremely rare and their chemistry almost completely unknown. They are both Lewis acids and electron donors, properties that are commonly associated with catalytically active late‐transition‐metal complexes. This double reactivity pattern ensures a rich and diverse chemistry. Herein we report the facile synthesis of several new boron(II) cations starting with a special diborane with two easily exchangeable triflate substituents. By increasing the π‐acceptor character of the neutral σ‐donor reaction partners, first reactions were developed in which the combined Lewis acidity and electron‐donor properties of boron(II) cations are applied for the reduction of organic molecules. The results of our study pave the way for applications of these unusual compounds in synthetic chemistry.
Noble‐Metal‐Free Single‐Atom Catalysts CuAl4O7–9− for CO Oxidation by O2
Authors: Zou Xiu‐Ping , Wang Li‐Na , Li Xiao‐Na , Liu Qing‐Yu , Zhao Yan‐Xia , Ma Tong‐Mei , He Sheng‐Gui
Published: July 2018

The single copper atom doped clusters CuAl4O7–9− can catalyze CO oxidation by O2. The CuAl4O7–9− clusters are the first group of experimentally identified noble‐metal free single atom catalysts for such a prototypical reaction. The reactions were characterized by mass spectrometry and density functional theory calculations. The CuAl4O9CO− is much more reactive than CuAl4O9− in the reaction with CO to generate CO2. One adsorbed CO is crucial to stabilize Cu of CuAl4O9− around +I oxidation state and promote the oxidation of another CO. The widely emphasized correlation between the catalytic reactivity of CO oxidation and Cu oxidation state can be understood at the strictly molecular level. The remarkable difference between Cu catalysis and noble‐metal catalysis was discussed.
Synthesis, structural characterization, antimicrobial, antioxidant and DNA binding studies of some novel homo‐binuclear Schiff base metal (II) complexes
Authors: Abdel Aziz Ayman A. , Shawky Ahmed , Khalil Mostafa M.H.
Published: July 2018

A novel bi‐nucleating Schiff base ligand, 6,6′‐(((1E,1′E)‐thiophene‐2,5‐diylbis (methaneylylidene))bis (azaneylylidene))bis (3,4‐dimethylaniline), and five binuclear M (II) complexes were synthesized. The bi‐nucleating Schiff base ligand and its metal complexes were characterized using various physicochemical techniques, e.g. elemental analyses, spectroscopic methods, conductivity and magnetic moment measurements. The low molar conductance of the complexes in dimethylsulfoxide shows their non‐electrolytic nature. The antibacterial activities were screened against pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Pseudomonas putida and Bacillus subtilis). The antifungal activity was screened against Aspergillus niger, Aspergillus flavus and Rhizoctonia bataicola. The antimicrobial activity data showed that the metal complexes are more potent than the parent Schiff base ligand against microorganisms. The antioxidant activities of the synthesized compounds were investigated through scavenging activity against 2,2‐diphenyl‐2‐picrylhydrazyl, superoxide anion, hydroxyl and 2,2′‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonic acid) radicals. The complexes have superior radical scavenging activity than the free ligand and the scavenging effects of the Cu (II) complex are stronger than those of the other complexes. DNA binding studies were performed using electronic spectroscopy, fluorometric competition studies and viscosity measurements. The data indicated that there is a marked enhancement in biocidal activity of the ligand under similar experimental conditions because of coordination with metal ions.
Synthesis of diaryl sulfides via nickel ferrite‐catalysed C─S bond formation in green media
Authors: Farzin Shiva , Rahimi Abdollah , Amiri Kamran , Rostami Abed , Rostami Amin
Published: July 2018

NiFe2O4 magnetic nanoparticles (MNPs) were synthesized, characterized and applied as an air‐stable, inexpensive and magnetically separable nanocatalyst for the synthesis of structurally diverse sulfides. Efficient methodologies were developed for the synthesis of unsymmetric diaryl sulfides via odourless and one‐pot reactions of triphenyltin chloride/S8 or arylboronic acid/S8 as thiolating agents with aryl halides or nitroarenes as starting materials in the presence of base (K2CO3 or NaOH) and NiFe2O4 MNPs as a catalyst in water or poly (ethylene glycol) as solvent at 80–110 °C. Free from ligand and the unpleasant smell of thiols and with the use of magnetically reusable nanocatalyst, green solvents and commercially available and cheap sulfur source and starting materials, these methods are more eco‐friendly and practical than available protocols for the synthesis of sulfides.
Structure–reactivity studies of chloro and isothiocyanato diorganotin (IV) complexes based on multidentate N‐donor ligands: Synthesis, spectral characterization and crystal structures
Authors: Momeni Badri Z. , Sefidabi Farzaneh , Khademi Saghi , Fathi Nastaran
Published: July 2018

The reaction of [SnMe2Cl2] with the bidentate ligand 4,7‐phenanthroline (4,7‐phen) resulted in the formation of [SnMe2Cl2 (4,7‐phen)]n (1a) which is probably a polymeric chain in solution. On the other hand, the reaction of [SnEt2Cl2] with 4,7‐phen afforded the complex [Sn2Et4Cl4 (κ1‐N‐4,7‐phen)2(μ‐κ2‐N,N‐4,7‐phen)] (1b) which dissociates in dimethylsulfoxide solution. The reaction of [SnR2Cl2] (R = Me, Et) with 2,2′‐biquinoline (biq) yielded the complexes [SnMe2Cl2 (κ2‐N,N‐biq)] (2a) and [SnEt2Cl2 (κ1‐N‐biq)2] (2b) in the solid state. Moreover, the reaction of [SnR2Cl2] (R = Me, Et) with the tridentate ligand 4′‐(2‐furyl)‐2,2′:6′,2″‐terpyridine (ftpy) resulted in the formation of ionic penta‐ and hexa‐coordinated tin complexes [SnMe2Cl (ftpy)][SnMe2Cl3] (3a) and [SnEt2Cl (ftpy)]Cl (3b). The reaction of [SnMe2 (NCS)2] with ftpy afforded the hepta‐coordinated complex [SnMe2 (NCS)2(ftpy)] (4a). The products were fully characterized using elemental analysis, and infrared, UV–visible, multinuclear (1H, 13C, 119Sn) NMR, DEPT‐135°, HH‐COSY and HSQC NMR spectroscopies. The crystal structure of complex 3a reveals that it contains the simultaneous presence of penta‐ and hexa‐coordinated tin (IV) atoms. Notably, the crystal structure of complex 4a shows that tin (IV) is hepta‐coordinated in a pentagonal bipyramidal geometry SnC2N5 by three nitrogen atoms of ftpy, two nitrogen atoms of NCS− and two Me groups with trans‐[SnMe2] configuration. These data indicate the influence of halide or pseudo‐halide group on the coordination number and geometry of tin. Hirshfeld surface analysis and two‐dimensional fingerprint plots were calculated for 3a and 4a which show the π–π interaction between molecules in the solid is relatively weak.
Rheological and thermal behaviours of a hyperbranched polycarbosilane
Authors: Piriou Cassandre , Viers Lucas , Lucas Romain , Bouzat Fabien , Laadoua Hatim , Champavier Yves , Foucaud Sylvie , Coelho Cristina , Babonneau Florence
Published: July 2018

A hyperbranched polymer, a precursor of silicon carbide (SiC), was successfully synthesized using a hydrosilylation reaction with Karstedt's catalyst. This reaction was optimized with the use of a rheometer coupled with an infrared spectrometer. The polymeric precursor was characterized using NMR and Fourier transform infrared spectroscopies, and dynamic rheology. The polymerization reaction was followed in situ by combined rheological and infrared measurements, indicating a gel‐like behaviour for alkene conversions higher than 0.55. Overall second‐order kinetics was determined for the hydrosilylation reaction. Pyrolysis at 1400 °C led to porous materials with β‐SiC and free carbon.
Highly selective adsorption of cadmium ions by water‐dispersible magnetic thioglycolic acid/graphene oxide composites
Authors: Saçmacı Şerife , Saçmacı Mustafa
Published: July 2018

A new selective and fast procedure based on magnetic dispersive solid‐phase extraction and zeta potential analysis is proposed for the determination of Cd (II) in some food samples. In the developed method, novel magnetic nanoparticles modified with thioglycolic acid were synthesized/characterized and also applied for quantitative determination of trace amounts of Cd (II) in food samples. The prepared nanoparticles were characterized via infrared spectroscopy, electron microscopy and adsorption–desorption experiments. These magnetic nanocomposites carrying Cd (II) could be easily separated from real samples simply by applying an external magnetic field; no filtration or centrifugation was necessary. Several parameters affecting the analytical performance, such as sample pH, amounts of nanocomposite sample, desorption solution volumes and coexisting ions, were investigated in detail. The detection limit of the method was 0.1 μg l−1 while the relative standard deviation was 1.2% for a Cd (II) concentration of 0.5 mg l−1. The proposed method was successfully applied to food sample analysis and standard reference material samples with satisfactory results, and excellent recoveries were obtained in the range 95–99% even when the matrix, such as sea water, was complex.
MeZnOMe‐mediated reaction of aldehydes with Grignard reagents: A glance into nucleophilic addition/Oppenauer oxidation pathway
Authors: Fu Ying , Ma Xian‐Zhen , Shi Chun‐Zhao , Shen Tong , Du Zhengyin
Published: July 2018

A novel organozincate of RMgX ⋅MeZnOMe ⋅LiCl type, formed in situ via transmetalation of Grignard reagent RMgBr ⋅LiCl with MeZnOMe, is shown to be an excellent organometallic species in the nucleophilic addition/Oppenauer oxidation of aldehydes to generate aromatic ketones in high yield. This transformation allows quick access to structurally diverse aryl, heteroaryl, benzyl and alkyl ketones with broad substrate scope and excellent functional group tolerance.
The enhanced biological activities of three Zn (II) complexes based on different 1,2,4‐triazole fungicides
Authors: Ren Guo‐yu , Li Jie , Wei Xu‐zhan , Zhou Jin‐hua , Yan Biao , Guo Zhao‐qi , Ren Ying‐hui , Sun Xiao‐hong , Ma Hai‐xia
Published: July 2018

In order to screen effective fungicides, three Zn (II) complexes, [ZnL14 (NO3)2]·2H2O·2EtOH (1), [ZnL24 (NO3)2] (2), and [ZnL34 (DMF)2](NO3)2 (3), (L1 = paclobutrazol, L2 = diniconazole, and L3 = hexaconazole), were synthesized and characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal XRD. The antifungal activities of these complexes were then evaluated against four selected fungi using the mycelial growth rate method. The resulting data indicate that all the complexes show the enhanced antifungal activities than the corresponding ligand and mixtures. And, the interactions between the metal salt and ligands in the three complexes seem to be synergistic. According to the study of the influence of the structures on the activity, complex 2 with C=C linkage and 2,4‐dichlorophenyl moieties enhances the bioactivity significantly, especially against Wheat gibberellic (II). Density functional theory (DFT) calculations were carried out to help explain the enhanced bioactivity of the Zn (II) complexes. Meanwhile, all complexes are excellent grow‐regulators, especially complex 3. The resulting data show that the complexes based on triazole fungicides have the potential applications in agriculture.
Synthesis, structure and property of diorganotin N‐[(3‐methoxy‐2‐oxyphenyl)methylene]tyrosinates
Authors: Tian Laijin , Han Lu , Yao Yanze , Zheng Xiaoliang , Liu Xijie , Lin Xianjie
Published: July 2018

Five new diorganotin N‐[(3‐methoxy‐2‐oxyphenyl)methylene] tyrosinates, R2Sn[2‐O‐3‐MeOC6H3CH=NCH (CH2C6H4OH‐4)COO] (R = Me, 1; Et, 2; Bu, 3; Cy, 4; Ph, 5), have been synthesized and characterized by elemental analysis, IR, NMR (1H, 13C and 119Sn) spectra, and the X‐ray single crystal diffraction. In non‐coordinated solvent, complexes 1–5 have penta‐coordinated tin atom. In the solid state, 1–3 are centrosymmetric dimmers in which each tin atom is seven‐coordinated in a distorted pentagonal bipyramid, and 4 displays discrete molecular structure with distorted trigonal bipyramidal geometry, and the tin atom of 5 is hexa‐coordinated and possess the distorted octahedral geometry with a coordinational methanol molecule. The intermolecular O‐H⋅⋅⋅O hydrogen bonds in 1–4 link molecules into the different one‐dimensional supramolecular chain with R22 (30) or R22 (20) macrocycles, and the molecules of 5 are joined into a two‐dimensional supramolecular network containing R44 (24) and R44 (28) two macrocycles. Bioassay results against human tumour cell HeLa indicated that 3‐5 belonged to the efficient cytostatic agents and the activity decreased in the order 4>3>5>2>1. The fluorescence determinations show the complexes may be explored for potential luminescent materials.
Graphene wrapped phthalocyanine: Enhanced oxidative desulfurization for dibenzothiophene in fuel
Authors: Zhang Gai , Liu Bulei , Zhou Hongwei , Yang Yan , Chen Weixing , Zhao Jianshe
Published: July 2018

Graphene wrapped metal phthalocyanine (MPc/RGO, M = Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+) composites are synthesized by a facile ‘in situ hydrothermal’ method, using graphene oxide, M (CH3COO)2 and phthalic anhydride as the precursors. A biomimetic catalytic system of MPc/RGO and molecular O2 have high activity for ultra‐deep removal of dibenzothiophene (DBT) in model oil containing n‐octane. Compared with pure graphene oxide and MPc, MPc/RGO composites displayed highly enhanced catalytic activity for the oxidation of dibenzothiophene in n‐octane. The conversion ratio of DBT was up to 97.51% after 180 min treatment at 60 °C and atmospheric pressure. The photostability of RGO/MPc composites photocatalystic degradation of dibenzothiophene was investigated. Mechanistic studies revealed that the RGO/MPc − O2· species were the main active intermediate via the π‐π stacking interaction of MPc and RGO. The RGO wrapped phthalocyanine materials offer great potential as active photocatalysts for degradation of thiophene derivatives in fuel.
Rhodium/Phosphine catalysed selective hydroformylation of biorenewable olefins
Authors: Jagtap Samadhan A. , Bhanage Bhalchandra M.
Published: July 2018

This work reports rhodium catalyzed selective hydroformylation of natural olefins like eugenol, estragole, anethole, prenol and isoprenol using biphenyl based Buchwald phosphine ligands (S‐Phos (L1), t‐Bu XPhos (L2), Ru‐Phos (L3), Johnphos (L4) and DavePhos (L5). Ru‐Phos (L3) ligand exhibited high impact on the hydroformylation of eugenol providing high selectivity (90%) of linear aldehyde as major product. In addition, internal natural olefins like anethole and prenol provided moderate to high selectivity (65% and 85% respectively) of branched aldehydes as a major products. The various reaction parameters such as influence of ligands, P/Rh ratio, syngas pressure, temperature, time and solvents have been studied. A high activity and selectivity gained on the way to the linear aldehydes it may be due to the bulky, steric cyclohexyl and isopropoxy groups present in L3 phosphine ligand. Moreover, this catalytic system was smoothly converting natural olefins into corresponding linear and branched aldehydes with higher selectivity under the mild reaction conditions.
Copper‐catalyzed C‐N coupling reaction of tosylhydrazones
Authors: Wu Xufeng , Li Lingyu , Jiang Wenlong , Zhou Lihong , Zeng Qingle
Published: July 2018

Tosylhydrazones are a kind of labile and highly reactive compounds, which are apt to be transformed into reactive diazo compounds and then into extremely reactive carbenes under the basic condition. In order to fulfil the valuable C‐N coupling reaction, diaryliodonium salts are evaluated and prove to be a class of efficient electrophiles. The reaction with ligand‐free copper salt as catalyst shows a wide range of substrate scope. A plausible mechanism is proposed.
Non‐Bonding Interactions Enable the Selective Formation of Branched Products in Palladium‐Catalyzed Allylic Substitution Reactions
Authors: Wang Ya‐Ni , Lu Liang‐Qiu , Xiao Wen‐Jing
Published: July 2018

Palladium‐catalyzed allylic substitution reactions have become established as an important tool for the construction of carbon−carbon and carbon−heteroatom bonds in modern organic synthesis. However, controlling the regioselectivity of this type of transformation to afford chiral branched products, in addition to controlling the enantioselectivity, is a significant challenge. Excitingly, controlling nonbonding interactions between the substituents on the π‐allyl−palladium intermediate and the nucleophile or palladium catalyst has been shown to be effective in achieving this goal. This Focus Review highlights representative advances in this field, according to the mode of non‐bonding interaction, including hydrogen‐bonding, electrostatic, and coordination interactions.
Diagnosis of Partially Observed Petri Net Based on Analytical Redundancy Relationships
Authors: Chouchane Amira , Khedher Atef , Nasri Othman , Kamoun Anas
Published: July 2018

In this paper, we design an efficient diagnosis technique for partially observed discrete event systems modeled by labeled Petri nets. The fault detection is based on analytical redundancy relationships derived from the nominal model. The decomposition of the Tun‐induced subnet to connected subgraphs allows determining the subgraphs that may contain faults. To appreciate the fault localization, a set of analytical redundancy relationships is etablished for each fault transition based on the fault model. The proposed diagnosis approach is independent of the length of the observed sequence and independent of the number of unobservable transitions. The detected faults with the proposed approach are faults which led to a change in the number of tokens in the net.
A Phenanthroimidazole‐based Fluorescent Turn‐Off Chemosensor for the Selective Detection of Cu2+ in Aqueous Media
Authors: Hwang Suh Mi , Chae Ju Byeong , Kim Cheal
Published: July 2018

A new phenanthroline‐based chemosensor 3‐(1H‐phenanthro[9,10‐d]imidazol‐2‐yl)benzene‐1,2‐diol (1) was synthesized for the recognition of Cu2+. Sensor 1 showed selective fluorescence quenching for Cu2+ in aqueous media. Detection limit (0.87 μM) for Cu2+ was much lower than WHO guideline (31.5 μM). Sensing property of 1 toward Cu2+ was studied by fluorescence and UV–Vis titrations, and Job plot and ESI‐MS analyses. Moreover, turn‐off fluorescence mechanism of 1 toward Cu2+ induced by intramolecular charge‐transfer (ICT) and ligand‐to‐metal charge‐transfer (LMCT) was well demonstrated by theoretical calculations.
Development of a colloidal gold nanoparticle‐based immunochromatographic strip for the one‐step detection of miroestrol and puerarin
Authors: Krittanai Supaluk , Kitisripanya Tharita , Udomsin Orapin , Tanaka Hiroyuki , Sakamoto Seiichi , Juengwatanatrakul Thaweesak , Putalun Waraporn
Published: July 2018

Pueraria candollei or White Kwao Krua (Leguminosae) is an indigenous plant in Thailand which has long been used in Thai traditional medicine. The tuberous root of this plant is widely used for rejuvenation, particularly in elder women. Among the bioactive compounds in P. candollei, miroestrol and puerarin exhibit estrogenic activity. This study aims to develop an immunochromatographic strip (ICS) with a colloidal gold‐based detection system for the simultaneous detection of miroestrol and puerarin in a one‐step analysis. The developed method is sensitive and specific for the detection of miroestrol and puerarin in raw materials and marketed products. The detection limits of miroestrol and puerarin were 0.15 and 4.5 μg, respectively. In addition, the results from the developed ICS were confirmed with an enzyme‐linked immunosorbent assay and presented a good correlation between these two methods. This is the first report on the development of an ICS that can detect miroestrol and puerarin in one step. The developed ICS provides a simplified method for the detection of miroestrol and puerarin in P. candollei and Pueraria spp.
Evaluating the organizational intention to implement an Environmental Management System: evidence from the Indonesian food and beverage industry
Authors: Salim Hengky K. , Padfield Rory , Yuzir Ali , Mohamad Shaza Eva , Kaida Naoko , Papargyropoulou Effie , Nakamura Shohei
Published: July 2018

The over‐exploitation of natural capital and unsustainable production practices has contributed to increased pollution, biodiversity loss, drought, and deforestation. The food and beverage (F&B) sector is one of the largest contributors to the Indonesian economy but it is also responsible for various environmental impacts. Implementing Environmental Management Systems (EMS) is one way to promote improved sustainable practices within organisations, particularly those within the F&B sector. This research investigates the drivers, barriers and incentives for implementing EMS and their causal relationships. Data were collected from 59 F&B companies in East Java, Indonesia. The results indicate that the implementation of EMS tends to be driven internally in an effort to enhance market competitiveness. There is a need for institutions to exert pressures to develop organizational capability to implement EMS. External barriers are significant impeding factors, while internal barriers do not have a direct link to EMS implementation. The moderating role of technical incentives underlines the need to improve infrastructure and policy to support EMS implementation. Theoretical and practical insights for governments and industries are also discussed.
Trends in incidence and associated risk factors of suicide mortality in patients with non‐small cell lung cancer
Authors: Zhou Huaqiang , Xian Wei , Zhang Yaxiong , Chen Gang , Zhao Shen , Chen Xi , Zhang Zhonghan , Shen Jiayi , Hong Shaodong , Huang Yan , Zhang Li
Published: July 2018

Lung cancer patients have an increased risk for committing suicide. But no comprehensive study about the suicide issues among non‐small‐cell lung cancer (NSCLC) patients has been published. We aimed to estimate the trend of suicide rate and identify the high‐risk group of NSCLC patients. Patients diagnosed with primary NSCLC were identified from Surveillance, Epidemiology, and End Results (SEER) database (1973‐2013). Suicide mortality rate (SMR) were calculated. Multivariable logistic regression was employed to find out independent risk factors for suicide. Among 495 889 NSCLC patients, 694 (0.14%) of them died from suicide. The suicide mortality rates have significantly decreased (before 1993: 0.21%, 1994‐2003: 0.16%, after 2004: 0.09%, P < .001). Male (OR 6.22, 95% CI: 4.96‐7.98, P < .001), white (OR 3.89, 95% CI: 2.66‐5.97, P < .001), being unmarried (OR 1.43, 95% CI: 1.22‐1.67, P < .001), the elderly (60‐74 vs <60: OR 1.24, 95% CI: 1.03‐1.50, P = .024, >75 vs <60: OR 1.31, 95% CI: 1.05‐1.63, P = .018) were independently associated with higher risk of suicide mortality. Surgery (OR: 1.44, 95% CI: 1.19‐1.73, P < .001) was also relative with higher risk of suicide. Our study observed significant decrease in suicide mortality among NSCLC patients in US over past decades. Older age, male sex, unmarried status, and surgery were risk factors of committing suicide. Clinicians should be aware of these high‐risk groups.
Body composition changes differ by gender in stomach, colorectal, and biliary cancer patients with cachexia: Results from a pilot study
Authors: Yoon Saunjoo L. , Grundmann Oliver , Williams Joseph J. , Gordan Lucio , George Thomas J.
Published: July 2018

Few studies have examined the possibility that cachexia may affect men and women differently. This pilot study assessed gender differences in body composition in stomach, colorectal, and biliary cancer patients with cachexia. A sample of 38 participants (Female: Male = 17:21, mean age 57.4 years) were included if they were undergoing chemotherapy and experienced weight loss of 5% or more over a 6‐month period. Bioelectrical impedance analysis (BIA) was applied to measure body composition. Phase angle (PA) and levels of extra‐/intracellular water (ECW; ICW) were determined. Data were analyzed first by gender and then compared to age‐ and gender‐matched healthy controls from the NHANES‐III dataset. PA was lower (P < .01) in both genders compared with healthy controls, and PA was lower in female patients compared with male patients (P = .03). Male cancer patients with lower PA also had lower ICW levels compared with healthy controls (r = .98, P < .01). For female patients, PA and ICW were negatively correlated (r = .897, P < .01). A lower ECW/ICW ratio was highly correlated (r = .969 for men, r = .639 for women) with increased PA in cancer patients. ICW changes are gender‐specific in patients with GI cancer. ECW/ICW ratios and PA may be suitable surrogate markers for gender‐specific changes in cell composition and health status.
Inhibition of CXCR4 regulates epithelial mesenchymal transition of NSCLC via the Hippo‐YAP signaling pathway
Authors: Zheng Chun‐Hui , Chen Xiao‐Mei , Zhang Fang‐Biao , Zhao Chun , Tu Shao‐Song
Published: July 2018

CXCR4 has been shown to play a key role in the metastasis of non‐small cell lung cancer (NSCLC). And CXCR may be associated with the Hippo—Yes kinase‐associated protein (YAP) pathway, thus involving in the occurrence and progression of NSCLC. This study aims to investigate the effect of CXCR4 inhibition on epithelial‐mesenchymal transition (EMT), invasion and migration of NSCLC cells via the Hippo‐YAP pathway. QRT‐PCR and Western blot were employed to detect CXCR4 expression in NSCLC cell lines. A549 and H1299 cells were treated with WZ811 (0, 10, 30, and 50 µM), and A549 cells were also divided into the Control, WZ811, YAP siRNA, and WZ811 + YAP groups. Wound‐healing, Transwell assay, immunofluorescent staining, and a luciferase reporter gene assay were performed in this experiment. Compared with human bronchial epithelial (HBE) cells, CXCR4 expression was up‐regulated in NSCLC cell lines. WZ811 increased E‐cadherin; decreased expression of Twist, vimentin, Snail, p‐YAP, CTGF, and BIRC5; blocked GTIIC reporter activity; and reduced migration and invasion of A549 cells, all in a dose‐dependent manner. YAP siRNA had a similar effect to WZ811 by inhibiting EMT, invasion and migration of A549 cells. However, compared with A549 cells in the YAP siRNA and WZ811 groups, cells in the WZ811 + YAP group showed a dramatically enhanced EMT phenotype as well as invasion and migration abilities. Inhibition of CXCR4 may reduce EMT, invasion and migration of NSCLC cells, thereby providing a new therapeutic target for NSCLC.
Suppressed expression of Cbl‐b by NF‐κB mediates icotinib resistance in EGFR‐mutant non‐small‐cell lung cancer
Authors: Zhang Tieqiong , Zheng Chunlei , Hou Kezuo , Wang Jinyao , Zhang Ye , Fan Yibo , Zhao Huan , Qu Xiujuan , Liu Yunpeng , Kang Jian , Che Xiaofang , Hu Xuejun
Published: July 2018

Although epidermal growth factor receptor tyrosine kinase inhibitor (EGFR‐TKI) could greatly improve the prognosis of NSCLC patients harboring activating EGFR mutations, drug resistance still remains a major obstacle to successful treatment. Our previous study found that the EGFR‐TKI icotinib could upregulate the expression of Casitas‐B‐lineage lymphoma protein‐B (Cbl‐b), an E3 ubiquitin ligase. In the present study, we aimed to clarify the potential role of Cbl‐b in the resistance to icotinib, and the underlying mechanisms using EGFR‐mutant cell lines. We found that icotinib inhibited the proliferation of mutant‐EGFR NSCLC cells (PC9 and HCC827), and upregulated the expression of Cbl‐b at both the protein and mRNA levels. Cbl‐b knockdown decreased the sensitivity of PC9 and HCC827 cells to icotinib, and partially restored icotinib‐inhibited AKT activation in PC9 cells. On the contrary, Cbl‐b overexpression could partly reverse the drug resistance in PC9 icotinib‐resistant cells (PC9/IcoR). Moreover, overexpressing p65, the main member of transcription factor NF‐κB family, reversed the icotinib‐mediated upregulation of Cbl‐b. Collectively, these data suggest that icotinib could upregulate Cbl‐b mediated by NF‐κB inhibition, and Cbl‐b contribute to the icotinib sensitivity in EGFR‐mutant NSCLC cells. This study highlights that low expression of Cbl‐b might be the key obstacles in the efficacy of icotinib therapy.
Men and women with borderline personality disorder resident in Dutch special psychiatric units in prisons: A descriptive and comparative study
Authors: van den Brink Chantal , Harte Joke M. , Denzel A. Dorina
Published: July 2018

Background

The overall prevalence of borderline personality disorder is well known, but characteristics of offender patients with the condition are less clear, especially among men.

Aim

Describe characteristics of men and women with borderline personality disorder in special psychiatric units in Dutch prisons on three domains: prevalence of child abuse, comorbidity of borderline personality disorder with other disorders, and clinical symptoms.

Methods

One hundred and sixty‐seven people were assigned to this study based on a Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM‐5) diagnoses retrieved from records. Other DSM‐5 diagnoses were also recorded. Two scales, the Dutch Historisch, Klinisch, Toekomst—Revisie and the international Brief Psychiatric Rating Scale—Expanded (BPRS‐E) were used to record child abuse and clinical symptoms, respectively.

Results

Prevalence rates of child abuse were high, but the men and women did not differ in this respect. The male offender patients were more likely than the women to have a comorbid substance use disorder, whereas the women were more likely to have a comorbid anxiety disorder. Intellectual disability was the most common comorbid Axis II disorder. The women were more likely than the men to have committed a fatal/nearly fatal index offence and showed higher rates of distress or behavioural disturbance on all five BPRS‐E factors.

Conclusions

This study provides evidence of the importance of in‐depth knowledge of presentations with borderline personality disorder specific to setting. Although we were unable to make direct comparisons with other samples, our figures suggest clinically relevant differences among offender patients from the more widely reported general samples. We also shed light on a sometimes underexposed group of men with borderline personality disorder and their clinical needs. More population‐specific intervention and follow‐up studies are now indicated.
A Mesoporous Carbon‐Supported and Cs‐promoted Ru Catalyst with Enhanced Activity and Stability for Sustainable Ammonia Synthesis
Authors: Nishi Masayasu , Chen Shih‐Yuan , Takagi Hideyuki
Published: July 2018

A mesoporous carbon‐supported Ru catalyst with Cs promotor and an open mesostructure (Cs−Ru/MPC) was prepared by a stepwise wet impregnation method and used for sustainable ammonia synthesis under mild reaction conditions using a wide range of space velocities (SV). The Cs−Ru/MPC catalyst showed higher activity and stability for ammonia synthesis than a reference catalyst with a microporous framework prepared by the same method (an active‐carbon‐supported and Cs‐promoted Ru catalyst (Cs−Ru/AC)). It was found that the mesoporous carbon framework is a suitable medium for the dispersion of the Ru nanoparticles within a narrow size distribution, and it also protected the small Ru nanoparticles against sintering during ammonia synthesis. However, the sintering of Ru nanoparticles on the outer surfaces of the Cs−Ru/AC catalyst was observed, resulting in its deactivation. The results suggest that the Cs−Ru/MPC catalyst is applicable to real operating conditions, where there may be short warm‐up and shut‐down periods for hydrogen production via the electrolysis of water using intermittently available renewable electricity.
Freestanding Cobalt‐Aluminum Oxides on USY Zeolite as an Efficient Catalyst for Selective Catalytic Reduction of NOx
Authors: Wang Bo , Zhang Jingyan , Ding Yu , Peng Honggen , Xu Hao , Guan Yejun , Wu Haihong , Wu Peng
Published: July 2018

The selective catalytic reduction of NOx with propane as reductant (C3H8‐SCR) is an attractive alternative for the depletion of NOx generated under lean burn condition. Herein, we developed a novel and low‐cost three‐dimensional CoOx@USY catalyst applied for catalytic reduction of NO with propane for the first time. The as‐fabricated hierarchical architecture was beneficial for exposing the active sites maximally, enhancing mass transports as well as integrating strongly interacted cobalt‐aluminum oxide together with the nature of USY zeolite. Serving as a SCR catalyst, the designed CoOx@USY yielded a remarkably elevated NO conversion efficiency due to the synergy between the Co−Al oxide shell and the USY zeolite core, showing promising application for the pollution abatement of nitric oxides. The reaction mechanism was also studied in detail trough the in situ DRIFTS technique. This work would provide new insights into the design and synthesis of transition metal‐based catalysts with a high‐efficiency for reducing NO emission.
Rhodamine 6G Radical: A Spectro (Fluoro) Electrochemical and Transient Spectroscopic Study
Authors: Slanina Tomáš , Oberschmid Teresa
Published: July 2018

A detailed study on the radical of rhodamine 6G, a key intermediate in photoredox catalysis, is presented. Various methods of its preparation (photoinduced electron transfer, electrochemistry), its spectroscopic characterization, stability, oxidation, photoionization and transient spectroscopic study have been investigated. Photooxidation of reduced rhodamine 6G has been established as a sensitive method for determination of dissolved oxygen. Photoionization of rhodamine 6G radical was found to be strongly solvent‐dependent and the released electrons were detected as photoinduced current in a spectroelectrochemical OTTLE cell. This process was identified as an extreme case of consecutive photoinduced electron transfer (conPET) mechanism. The electrofluorochromism of rhodamine 6G radical has been studied by a novel apparatus suitable for simultaneous analysis of electrochemical, absorption and emission properties.
The Size Effect of PdCu Bimetallic Nanoparticles on Oxygen Reduction Reaction Activity
Authors: Yang Yang , Dai Changqing , Wu Dengfeng , Liu Zhiping , Cheng Daojian
Published: July 2018

It is one of the basic objectives for heterogeneous catalysis to understand the particle size effect of nanoparticles (NPs) on their activity. However, such a particle size effect on the activity of bimetallic NPs is still in question. Here, we demonstrate an efficient ligand‐assisted technique for preparing PdCu NPs in four different sizes (9.3 nm, 7.1 nm, 6.3 nm and 5.8 nm) and explore the relationship between particle size and their oxygen reduction reaction (ORR) activity as a benchmark. As a general trend, ORR activity decreases as bimetallic particle size increases. It is found that the 5.8 nm‐PdCu NPs/C with the smallest size shows the best catalytic activity for ORR among these NPs, which exceeds the ORR activity of commercial Pt/C catalysts. Density functional theory (DFT) calculations confirm that, with the increase of bimetallic particle size, the edges and corners become less, and, accordingly, the adsorption energies of O atom and charge distribution of the particle are closer to the bulk phase, leading to the decrease of ORR catalytic activity. Our results provide a useful size controlled strategy and reveal the relationship between bimetallic particle size and reaction activity.
One‐Step Synthesis of 3D‐Sandwiched Na3V2(PO4)2O2F@rGO Composites as Cathode Material for High‐Rate Sodium‐Ion Batteries
Authors: Chen Hao , Mi Hongwei , Sun Lingna , Zhang Peixin , Li Yongliang
Published: July 2018

Na3V2(PO4)2O2F@reduced graphene oxide composites are rapidly synthesized by one‐step microwave‐assisted hydrothermal method within 1 h without any following energy‐consuming process. The composite shows a three‐dimensional sandwiched structure with carbon wrapping and is applied as cathode material for sodium‐ion batteries. It delivers a reversible capacity of 100.5 mAh g−1 and a capacity retention rate of 84.9 % at 20 C after 2000 cycles, exhibiting excellent rate capability and cyclability. This superior electrochemical performance is attributed to the synergetic effect from the enhanced electronic conductivity and the improved electrochemical kinetic behavior.
Iridium‐Induced Regioselective B−H and C−C Activations at Azo‐Substituted o‐Carboranes
Authors: Gao Yang , Cui Peng‐Fei , Aznarez Francisco , Jin Guo‐Xin
Published: July 2018

p‐Methoxybenzeneazo‐substituted o‐carboranes have been synthesized and their reactivity with half‐sandwich iridium and rhodium complexes has been investigated in detail. A variety of solvent‐ and base‐dependent, highly site‐selective B−H and C−C σ‐bond activations at the C/B cage have been observed. While the use of CH3OH leads to the formation of metallacarboranes, o‐carborane clusters undergo cyclometallation reactions involving B(6)−H, B(4)−H or a rare B(7)−H activation in CH2Cl2. The synthesis of a unique pseudo‐closo‐iridacarborane through a very unconventional metal‐mediated Ccage−Ccage activation is described in this contribution.
Fluorescent Trimethylated Naphthyridine Derivative with an Aminoalkyl Side Chain as the Tightest Non‐aminoglycoside Ligand for the Bacterial A‐site RNA
Authors: Sato Yusuke , Rokugawa Masafumi , Ito Sho , Yajima Sayaka , Sugawara Hiroki , Teramae Norio , Nishizawa Seiichi
Published: July 2018

The bacterial ribosomal decoding region of the aminoacyl‐tRNA site (A‐site) is one of the most validated target RNAs for antibiotic agents. Although natural aminoglycosides are well‐characterized A‐site binding ligands, high off‐target effects and the growing emergence of bacterial resistance against aminoglycosides limit their clinical use. To circumvent these concerns with the aminoglycoside family, non‐aminoglycoside A‐site binding ligands have great potential as novel antibiotics against bacterial infections. This work describes a new class of small heterocyclic ligands based on the 2‐amino‐5,6,7‐trimethyl‐1,8‐naphthyridine (ATMND) structure for the bacterial (Escherichia coli) A‐site. ATMND possessing an aminoethyl side chain is found to strongly and selectively bind to the internal loop of the A‐site (Kd=0.44 μm; pH 7.0, I=0.06 m, 5 °C). Significantly, this ligand shows the tightest binding reported to date among non‐aminoglycoside ligands. The binding study based on the thermodynamics and molecular modelling reveals key molecular interactions of ATMND‐C2‐NH2 for high affinity to the A‐site. This ligand is also demonstrated to be applicable to the fluorescence indicator displacement assay for assessing ligand/A‐site interactions.
Chemical Tuning of Zwitterionic Ionic Liquids for Variable Thermophysical Behaviours, Nanostructured Aggregates and Dual‐Stimuli Responsiveness
Authors: Biswas Yajnaseni , Ghosh Pratyush , Mandal Tarun K.
Published: July 2018

The design and synthesis of a series of zwitterionic ionic liquids (ZILs) to understand the structure–property relationship towards an increase of the thermal stability, a variation of the glass transition temperature, the shape‐tuning of nanostructured aggregates and the tuning of the stimuli responsiveness are demonstrated. The substitution reaction of imidazole with various aliphatic and aromatic bromides followed by the reaction of the corresponding substituted imidazoles with bromoalkyl carboxylic acids of varying spacer length produces the ZILs. In aqueous solution, a ZIL molecule either exist in its ionic liquid (substituted imidazolium bromide) form or its zwitterionic (substituted imidazolium alkyl carboxylate) form with an isoelectric point (pI) depending on the pH value of the solution. Upon changing the pH to near or above the pI, the aqueous ZIL solution undergoes transition from a transparent to a turbid phase due to the formation of insoluble hierarchical nanostructured aggregates of various morphologies, such as spheres, tripods, tetrapods, fern‐like, flower‐like, dendrites etc. depending on the pH of the solution and the nature of the alkyl/vinyl/aryl substituents. Upon heating the solution a phase transition occurs from turbid to transparent, exhibiting a distinct reversible upper critical solution temperature (UCST)‐type cloud point (Tcp). It is observed that the cloud point varies with the nature of the substituent, an increase of the concentration of the ZIL as well as with changes of the pH of the solution.
Post‐Assembly Reactivity of N‐Aryl Iminoboronates: Reversible Radical Coupling and Unusual B−N Dynamic Covalent Chemistry
Authors: Keyzer Evan N. , Sava Alexandru , Ronson Tanya K. , Nitschke Jonathan R. , McConnell Anna J.
Published: July 2018

Post‐assembly reaction of a dynamic covalent iminoboronate system following addition of Cp2Co resulted in the formation of a series of new reductively coupled dianionic dimers via C−C bond formation. The dimers formed as a mixture of BN‐containing isomeric products: diastereomers rac5 and meso5, with coupled five‐membered rings, and enantiomeric rac6, with a fused six‐membered ring bicyclic system from C−C bond formation and rearrangement of the B−N bonds. Each isomer was identified using 1H NMR spectroscopy in combination with single crystal X‐ray structure determination. Interestingly, interconversion between the coupled five‐membered rings (rac5) and fused bicyclic systems (rac6) was found to occur through an unprecedented breaking and reforming of the B−N covalent bond. Further, the coupled products could be converted quantitatively back to their iminoboronate precursors with addition of the electron abstractor Ph3C+.
The Importance of Length and Flexibility of Macrocycle‐Containing Molecular Translocators for the Synthesis of Improbable [2]Rotaxanes
Authors: Riss‐Yaw Benjamin , Clavel Caroline , Laurent Philippe , Waelès Philip , Coutrot Frédéric
Published: July 2018

This work reports on the use of molecular translocators to capture a dibenzo‐24‐crown‐8 (DB24C8) and then release it onto targeted molecular axles to afford, after removal of the translocator, [2]rotaxanes that do not hold any template site. Various translocators were studied and successfully aided the synthesis, with more or less efficacy, of [2]rotaxanes of different lengths. During the releasing step, the DB24C8 macrocycle shuttles along the thread, and the localization of the macrocycle might be driven by steric repulsion on the translocator part and/or electronic attraction of the targeted part of the axle to be encircled, which depends on both the nature of the translocator and the targeted thread to be encircled.
Organocatalytic Arylation of α‐Ketoesters Based on Umpolung Strategy: Phosphazene‐Catalyzed SNAr Reaction Utilizing [1,2]‐Phospha‐Brook Rearrangement
Authors: Kondoh Azusa , Aoki Takuma , Terada Masahiro
Published: July 2018

An organocatalytic arylation of α‐ketoesters was developed on the basis of umpolung strategy. Phosphazene P2‐tBu efficiently catalyzes the three‐component coupling reaction of α‐ketoesters, a silylated secondary phosphite, and electron‐deficient fluoroarenes to provide α‐hydroxyester derivatives possessing an electron‐deficient aryl group at the α‐position. The reaction involves the catalytic generation of α‐oxygenated ester enolates from α‐ketoesters through the [1,2]‐phospha‐Brook rearrangement followed by the SNAr reaction.
Suicidal ideation in patients with coronary heart disease and hypertension: Baseline results from the DEPSCREEN‐INFO clinical trial
Authors: Lehmann Marco , Kohlmann Sebastian , Gierk Benjamin , Murray Alexandra M. , Löwe Bernd
Published: July 2018

Background

A high proportion of cardiac patients suffers from depression, which is an antecedent for suicidal ideation. This study identifies clinical vulnerabilities for suicidal ideation in cardiac patients.

Methods

The primary outcome of the study was severity of suicidal ideation as measured with the Patient Health Questionnaire (PHQ‐9) item No. 9. Covariates were demographics, cardiac characteristics (i.e., Canadian Cardiovascular Society angina rating of chest pain and New York Heart Association rating of shortness of breath), depression (PHQ‐8,i.e., PHQ‐9 minus item No. 9), anxiety (Generalized Anxiety Disorder‐7, GAD‐7), somatic symptoms (PHQ‐15), illness perception (Brief‐Illness Perception Questionnaire), and health‐related quality of life (EuroQol‐5D, EQ 5D).

Results

Data from 1,976 patients were analysed. At least 14% (95% CI [12%, 16%]) of patients indicated suicidal ideations within the last 2 weeks. Bivariate analyses yielded associations between suicidal ideation and higher levels of depression severity, anxiety severity, somatic symptom burden, chest pain, shortness of breath, negative illness perceptions, reduced health‐related quality of life, and a higher probability of living alone (all p < 0.001). A multivariable ordinal regression revealed depression severity and anxiety severity to show the highest associations with suicidal ideation (ORPHQ‐8 = 1.22, p < 0.001; ORGAD‐7 = 1.09, p < 0.001). Having a defibrillator implant was associated with a lower probability of suicidal ideation (OR = 0.27, p = 0.017).

Conclusions

This study identified several clinical vulnerabilities of suicidal ideation. The results stress the importance of screening for suicidal ideation in clinical practice.
Investigation of Electromagnetic Interference Shielding Effectiveness of CZ Grown Ge Optical Windows
Authors: Çat Yunus , Baran Veysel , Afacan Gönenç , Coşar Mustafa Burak , Özçelik Süleyman
Published: July 2018

In this study, different Ge IR optical windows are produced and their electromagnetic interference (EMI) shielding performances are investigated. Three Ge single crystals with different doping concentrations are grown by the Czochralski (CZ) technique. Optical windows are obtained after the slicing, lapping, and polishing processes are examined. Formation of (111)‐oriented single crystal is observed from the X‐ray diffraction (XRD) pattern. In addition, IR transmission of the crystals is measured around 45% in the range of 2–12 µm using Fourier transform infrared spectrometer (FTIR) spectrometer. EMI shielding effectiveness (SE) of the windows is determined in a flanged coaxial SE tester developed for outer diameter as 1 inch. SE results are evaluated by taking into account both resistivity, thickness of the samples and limitations of measurement fixture.
Simulation study on the vapour shielding at solid walls under transient heat loads using weighted particle model
Authors: Ibano K. , Kikuchi Y. , Tanaka A. , Togo S. , Lee H. T. , Ueda Y. , Takizuka T.
Published: July 2018

Vapour shielding at solid walls is expected for a future fusion reactor in case of large heat load due to transient events. In order to estimate the dissipation of the incoming heat flux by the vapour shielding, a simulation code called PIXY, using a weighted particle model, is developed. First, a validation study is undertaken. Vapour shielding of an aluminium‐coated tungsten specimen was experimentally observed in a plasma gun device. Results are reproduced by the PIXY simulation. Then, the code is applied to the transient edge‐localized mode (ELM) heat flux for the reactor condition. It was found that the ion–neutral collision, as well as radiative cooling, is a dominant phenomenon for the heat flux dissipation in both cases. As the maximum heat flux increases, oscillating phenomena appear remarkably, which have been observed in other experimental studies on vapour shielding.