bluuebunny/crossref_metadata_2025 huggingface dataset:
Visualizing Formation of Intermetallic PdZn in a Palladium/Zinc Oxide Catalyst: Interfacial Fertilization by PdHx
Authors: Niu Yiming , Liu Xi , Wang Yongzhao , Zhou Song , Lv Zhengang , Zhang Liyun , Shi Wen , Li Yongwang , Zhang Wei , Su Dang Sheng , Zhang Bingsen
Published: January 2019

Controllable synthesis of well‐defined supported intermetallic catalysts is desirable because of their unique properties in physical chemistry. To accurately pinpoint the evolution of such materials at an atomic‐scale, especially clarification of the initial state under a particular chemical environment, will facilitate rational design and optimal synthesis of such catalysts. The dynamic formation of a ZnO‐supported PdZn catalyst is presented, whereby detailed analyses of in situ transmission electron microscopy, electron energy‐loss spectroscopy, and in situ X‐ray diffraction are combined to form a nanoscale understanding of PdZn phase transitions under realistic catalytic conditions. Remarkably, introduction of atoms (H and Zn in sequence) into the Pd matrix was initially observed. The resultant PdHx is an intermediate phase in the intermetallic formation process. The evolution of PdHx in the PdZn catalyst initializes at the PdHx/ZnO interfaces, and proceeds along the PdHx ⟨111⟩ direction.
Acyl‐Phosphide Anions via an Intermediate with Carbene Character: Reactions of K[PtBu2] and CO
Authors: Xu Maotong , Jupp Andrew R. , Stephan Douglas W.
Published: January 2019

The analogy of the reactivity of group 1 phosphides to that of FLPs is further demonstrated by reactions with CO, affording a new synthetic route to acyl‐phosphide anions. The reaction of [K(18‐crown‐6)][PtBu2] (1) with CO affords [(18‐crown‐6)K⋅THF2][Z‐tBuP=C(tBu)O] (2⋅THF2) as the major product, and the minor product [K6(18‐crown‐6)][(tBu2PCO)2]3 (3). Species 2 reacts with either BPh3 or additional CO to give [K(18‐crown‐6)][(Ph3B)tBuPC(tBu)O] (4) and [K(18‐crown‐6)][(OCtBu)2P] (5), respectively. The acyl‐phosphide anion 2 is thought to be formed by a photochemically induced radical process involving a transient species with triplet carbene character, prompting 1,2‐tert‐butyl group migration. A similar process is proposed for the subsequent reaction of 2 with CO to give 5.
Artificial K+Channels Formed by Pillararene‐Cyclodextrin Hybrid Molecules: Tuning Cation Selectivity and Generating Membrane Potential
Authors: Xin Pengyang , Kong Huiyuan , Sun Yonghui , Zhao Lingyu , Fang Haodong , Zhu Haofeng , Jiang Tao , Guo Jingjing , Zhang Qian , Dong Wenpei , Chen Chang‐Po
Published: January 2019

A class of artificial K+channels formed by pillararene‐cyclodextrin hybrid molecules have been designed and synthesized. These channels efficiently inserted into lipid bilayers and displayed high selectivity for K+over Na+in fluorescence and electrophysiological experiments. The cation transport selectivity of the artificial channels is tunable by varying the length of the linkers between pillararene and cyclodexrin. The shortest channel showed specific transmembrane transport preference for K+over all alkali metal ions (selective sequence: K+> Cs+> Rb+> Na+> Li+), and is rarely observed for artificial K+channels. The high selectivity of this artificial channel for K+over Na+ensures specific transmembrane translocation of K+, and generated stable membrane potential across lipid bilayers.
Efficient Homogeneous Electrocatalytic Water Oxidation by a Manganese Cluster with an Overpotential of Only 74 mV
Authors: Ghosh Totan , Maayan Galia
Published: January 2019

Water electrolysis is among the simplest method for generating hydrogen as an alternative renewable fuel. A major challenge associated with this process is the development of cheap, simple, and environmentally benign catalysts that lead to a minimum overpotential for water oxidation. Inspired by the Mn4CaOx cluster that catalyzes water oxidation in photosystem II, described here is the synthesis and characterization of the manganese cluster [Mn12O12(O2CC6H2(OH)3)16(H2O)4] (Mn12TH) along with its electrocatalytic activity at pH 6. Electrochemical, spectroscopic, and electron microscopy studies show that Mn12TH is a homogeneous electrocatalyst for water oxidation and enables oxygen evolution with a reaction rate of 22 s−1, high Faradic efficiency (93 %), and an overpotential of only 74 mV, the lowest reported to date. Based on the electrochemical data, the organic ligands, which can be described as the second coordination sphere of the catalytic manganese core, play a key role in facilitating the oxidation process and accelerating the reaction.
Synthesis, crystal structure, DNA/bovine serum albumin binding and antitumor activity of two transition metal complexes with 4‐acylpyrazolone derivative
Authors: Zhang Yan‐Ping , Li Yue , Xu Guan‐Cheng , Li Jin‐Yu , Luo Hua‐Ying , Li Jin‐Yao , Zhang Li , Jia Dian‐Zeng
Published: January 2019

Two new complexes, namely [Cu6L6] (1) and [Zn(HL)2] (2) (H2L = N‐(1‐phenyl‐3‐methyl‐4‐propenylidene‐5‐pyrazolone)‐2‐furancarboxylic acid hydrazide), have been synthesized and characterized. Single crystal X‐ray analysis indicates that complex 1 has a hexanuclear structure and complex 2 exhibits a mononuclear structure. The DNA/bovine serum albumin (BSA) binding properties of complexes 1 and 2 were investigated by absorption spectroscopy and fluorescence quenching. Both complexes could effectively intercalate to DNA with calculated quenching constants of 2.6 × 105 and 1.25 × 105 M−1, respectively. The quenching mechanism of the intrinsic fluorescence of BSA by the complexes was found to be a static one. The cytotoxicities of 1 and 2 were investigated in two human tumor cell lines, human esophageal cancer cells (Eca‐109) and cervical cancer cells (HeLa). Complex 1 exhibits higher antitumor activity than 2. Furthermore, 1 can inhibit HeLa cells by inducing apoptosis and G0/G1 phase cell cycle arrest. All results demonstrate that 1 and 2 both have DNA/BSA binding capacity and antitumor activity.
NiFe2O4 as a magnetically recoverable nanocatalyst for odourless C–S bond formation via the cleavage of C–O bond in the presence of S8 under mild and green conditions
Authors: Atashkar Bahareh , Rostami Amin , Rostami Abed , Zolfigol Mohammad Ali
Published: January 2019

We present green methodologies for one‐pot and odourless syntheses of unsymmetric and symmetric diaryl sulfides via C─O bond activation using NiFe2O4 magnetic nanoparticles as a reusable heterogeneous nanocatalyst. The synthesis of unsymmetric sulfides is performed using the cross‐coupling reaction of phenolic esters such as acetates, triflates and tosylates with arylboronic acid/S8 or triphenyltin chloride/S8 as thiolating agents in the presence of base and NiFe2O4 magnetic nanoparticles as a catalyst in poly(ethylene glycol) as solvent at 60–85°C. Also, the synthesis of symmetric diaryl sulfides from phenolic compounds using S8 as the sulfur source and NiFe2O4 as catalyst in dimethylformamide at 120°C is described. Using these protocols, the syntheses of various unsymmetric and symmetric sulfides become easier than using the available protocols due to the use of a magnetically reusable bimetallic nanocatalyst and avoiding the use of thiols and aryl halides.
Synthesis and biological evaluation of sphingosine kinase 2 inhibitors with anti‐inflammatory activity
Authors: Vettorazzi Marcela , Vila Laura , Lima Santiago , Acosta Lina , Yépes Felipe , Palma Alirio , Cobo Justo , Tengler Jan , Malik Ivan , Alvarez Sergio , Marqués Patrice , Cabedo Nuria , Sanz María J. , Jampilek Josef , Spiegel Sarah , Enriz Ricardo D.
Published: January 2019

The synthesis of inhibitors of SphK2 with novel structural scaffolds is reported. These compounds were designed from a molecular modeling study, in which the molecular interactions stabilizing the different complexes were taken into account. Particularly interesting is that 7‐bromo‐2‐(2‐phenylethyl)‐2,3,4,5‐tetrahydro‐1,4‐epoxynaphtho[1,2‐b]azepine, which is a selective inhibitor of SphK2, does not exert any cytotoxic effects and has a potent anti‐inflammatory effect. It was found to inhibit mononuclear cell adhesion to the dysfunctional endothelium with minimal impact on neutrophil–endothelial cell interactions. The information obtained from our theoretical and experimental study can be useful in the search for inhibitors of SphK2 that play a prominent role in different diseases, especially in inflammatory and cardiovascular disorders.
A novel screening method for potential naringinase‐producing microorganisms
Authors: Patil Satish V. , Koli Sunil H. , Mohite Bhavana V. , Patil Rahul P. , Patil Rohini R. , Borase Hemant P. , Patil Vikas S.
Published: January 2019

Naringinase has high industrial importance, and the progress in naringinase research is still quite slow. The unavailability of an effective, simple screening method, which will be applicable to different microorganisms such as bacteria, fungi, and actinomycetes, is one of the main reasons for this gap. Therefore, a simple plate assay was developed for effective screening of microorganisms for naringinase by exposing to iodine vapors. This plate assay will fill the technological void for simple screening method and will lead to screen more potent industrially important naringinase‐producing microorganisms.
Elusive Dehydroalanine Derivatives with Enhanced Reactivity
Authors: Aydillo Carlos , Mazo Nuria , Navo Claudio D. , Jiménez‐Osés Gonzalo
Published: January 2019

For the first time, a simple methodology for the chemical synthesis and use of highly reactive 4‐methylenoxazol‐5(4H)‐ones from serine is presented. These dehydroalanine derivatives, which resemble the natural 4‐methylidenimidazole‐5‐one (MIO) cofactor present in lyases and aminomutases, undergo rapid reaction with carbon nucleophiles such as silyl enol ethers, as well as cycloaddition reactions with diazo compounds and reactive dienes, under very mild conditions and without any need for metal catalysts or ring‐strain activation, offering potential for bioconjugation.
Bimodal Detection of Proteins by 129Xe NMR and Fluorescence Spectroscopy
Authors: Mari Emilie , Bousmah Yasmina , Boutin Céline , Léonce Estelle , Milanole Gaelle , Brotin Thierry , Berthault Patrick , Erard Marie
Published: January 2019

A full understanding of biological phenomena involves sensitive and noninvasive detection. Herein, we report the optimization of a probe for intracellular proteins that combines the advantages of fluorescence and hyperpolarized 129Xe NMR spectroscopy detection. The fluorescence detection part is composed of six residues containing a tetracysteine tag (−CCXXCC−) genetically incorporated into the protein of interest and of a small organic molecule, CrAsH. CrAsH becomes fluorescent if it binds to the tetracysteine tag. The part of the biosensor that enables detection by means of 129Xe NMR spectroscopy, which is linked to the CrAsH moiety by a spacer, is based on a cryptophane core that is fully suited to reversibly host xenon. Three different peptides, containing the tetracysteine tag and four organic biosensors of different stereochemistry, are benchmarked to propose the best couple that is fully suited for the in vitro detection of proteins.
Emissive Synthetic Cofactors: A Highly Responsive NAD+Analogue Reveals Biomolecular Recognition Features
Authors: Feldmann Jonas , Li Yao , Tor Yitzhak
Published: January 2019

Apart from its vital function as a redox cofactor, nicotinamide adenine dinucleotide (NAD+) has emerged as a crucial substrate forNAD+‐consuming enzymes, including poly(ADP‐ribosyl)transferase 1 (PARP1) and CD38/CD157. Their association with severe diseases, such as cancer, Alzheimer's disease, and depressions, necessitates the development of new analytical tools based on traceableNAD+surrogates. Here, the synthesis, photophysics and biochemical utilization of an emissive, thieno[3,4‐d]pyrimidine‐basedNAD+surrogate, termedNthAD+, are described. Its preparation was accomplished by enzymatic conversion of syntheticthATPby nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1). The new NAD+analogue possesses useful photophysical features including redshifted absorption and emission maxima as well as a relatively high quantum yield. Serving as a versatile substrate,NthAD+was reduced by alcohol dehydrogenase (ADH) toNthADHand affordedthADP‐ribose (thADPr) upon hydrolysis byNAD+‐nucleosidase (NADase). Furthermore,NthAD+was engaged in cholera toxin A (CTA)‐catalyzed mono(thADP‐ribosyl)ation, but was found incapable in promoting PARP1‐mediated poly(thADP‐ribosyl)ation. Due to its high photophysical responsiveness,NthAD+is suited for spectroscopic real‐time monitoring. Intriguingly, and as an N7‐lacking NAD+surrogate, the thieno‐based cofactor showed reduced compatibility (i.e., functional similarity compared to nativeNAD+) relative to its isothiazolo‐based analogue. The distinct tolerance, displayed by diverse NAD+producing and consuming enzymes, suggests unique biological recognition features and dependency on the purine N7 moiety, which is found to be of importance, if not essential, for PARP1‐mediated reactions.
Thermally Activated Delayed Fluorescence Materials: Towards Realization of High Efficiency through Strategic Small Molecular Design
Authors: Liang Xiao , Tu Zhen‐Long , Zheng You‐Xuan
Published: January 2019

Thermally activated delayed fluorescence (TADF) is one of the most intriguing and promising discoveries towards realization of highly‐efficient organic light emitting diodes (OLED) utilizing small molecules as emitters. It has the capability of manifesting all excitons generated during the electroluminescent processes, consequently achieving 100 % of internal quantum efficiency. Since the report of the first efficient OLED based on a TADF small molecule in 2012 by Adachi et al., the quest for optimal TADF materials for OLED application has never stopped. Various TADF molecules bearing different design concepts and strategies have been designed and produced, with the aim to boost the overall performances of corresponding OLEDs. In this minireview, the general principles of TADF molecular design based on three basic categories of TADF species: twisted intramolecular charge transfer (TICT), through‐space charge transfer (TSCT) and multi‐resonance induced TADF (MR‐TADF) are discussed in detail. Several key aspects with respect to each category, as well as some effective methods to enhance the efficiency of TADF materials and corresponding OLEDs from the molecular engineering perspectives, are summarized and discussed to exhibit a general landscape of TADF molecular design to a wide variety of scientific researchers within this particular disciplinary area.
Extremely Photostable Electron‐Deficient Phthalocyanines that Generate High Levels of Singlet Oxygen
Authors: Furuyama Taniyuki , Miyaji Yusuke , Maeda Kazuya , Maeda Hajime , Segi Masahito
Published: January 2019

Invited for the cover of this issue is the group of Taniyuki Furuyama at Kanazawa University. The image depicts photostable electron‐withdrawing group substituted phthalocyanine against singlet oxygen. Read the full text of the article at 10.1002/chem.201805082.
Anti‐Markovnikov Hydroazidation of Alkenes by Visible‐Light Photoredox Catalysis
Authors: Wang Juan‐Juan , Yu Wei
Published: January 2019

The anti‐Markovnikov hydroazidation of alkenes has been accomplished under visible‐light irradiation by using [Ir(dF(CF3)ppy)2(dtbbpy)]PF6 as the photocatalyst and trimethylsilyl azide as the azidating agent. The reactions were greatly facilitated by water, the beneficial effect of which can be attributed to its participation in the reaction as the hydrogen donor, as indicated by deuterium isotope experiments. The reactions proceed under solvent free conditions in the presence of water. 4‐Dimethylaminopyridine also exhibited a beneficial effect on the reactions. The present method enabled hydroazidation of several types of unactivated alkenes with good yields and high regioselectivity.
Hydride Pinning Pathway in the Hydrogenation of CO2 to Formic Acid on Dimeric Tin Dioxide
Authors: Sarma Plaban Jyoti , Baruah Satyajit Dey , Logsdail Andrew , Deka Ramesh Chandra
Published: January 2019

Capture of CO2 and its conversion into organic feedstocks are increasingly needed as society moves towards a renewable energy economy. Here, a hydride‐assisted selective reduction pathway is proposed for the conversion of CO2 to formic acid (FA) over SnO2 monomers and dimers. Our density functional theory calculations infer a strong chemisorption of CO2 on SnO2 clusters forming a carbonate structure, whereas heterolytic cleavage of H2 provides a new pathway for the selective reduction of CO2 to formic acid at low overpotential. Among the two investigated pathways for reduction of CO2 to HCOOH, the hydride pinning pathway is found promising with a unique selectivity for HCOOH. The negatively‐charged hydride forms on the cluster during the dissociation of H2 and facilitates the formation of a formate intermediate, which determines the selectivity for FA over the alternative CO and H2 evolution reaction. It is confirmed that SnO2 clusters exhibit a different catalytic behaviour from their surface equivalents, thus offering promise for future work investigating the reduction of CO2 to FA via a hydride pinning pathway at low overpotential and CO2 capturing.
The effects of e‐cigarette minimum legal sale age laws on youth substance use
Authors: Dave Dhaval , Feng Bo , Pesko Michael F.
Published: January 2019

We use difference‐in‐differences models and individual‐level data from the national and state Youth Risk Behavior Surveillance System from 2005 to 2015 to examine the effects of e‐cigarette minimum legal sale age (MLSA) laws on youth cigarette smoking, alcohol consumption, and marijuana use. Our results suggest that these laws increased youth smoking participation by about one percentage point and approximately half of the increased smoking participation could be attributed to smoking initiation. We find little evidence of higher cigarette smoking persisting beyond the point at which youth age out of the laws. Our results also show little effect of the laws on youth drinking, binge drinking, and marijuana use. Taking these together, our findings suggest a possible unintended effect of e‐cigarette MLSA laws—rising cigarette use in the short term while youth are restricted from purchasing e‐cigarettes.
Order flow dynamics for prediction of order cancelation and applications to detect market manipulation
Authors: Martínez Miranda Enrique , Phelps Steve , Howard Matthew J.
Published: January 2019

In this work, a methodology is proposed to detect and predict the intention of cancelation of a large order at an optimal event‐time horizon by analyzing real order flow market data. We achieve this by reconstructing the full history of the limit order book and formulate the case as a binary classification supervised learning problem. The results presented in this study suggest that using the information at the microstructure level of the order book is highly efficient for predicting and detecting the cancelation of the large order than using information at the macrostructure level, and that predicting the cancelation is marginally outperformed by the detection case. With this, we make a step forward in identifying potential orders related to price manipulation but the results can be used by institutional traders to anticipate adversary market impact produced by large orders.
ETS variant 5 promotes colorectal cancer angiogenesis by targeting platelet‐derived growth factor BB
Authors: Cheng Xi , Jin Zhijian , Ji Xiaopin , Shen Xiaonan , Feng Haoran , Morgenlander William , Ou Baochi , Wu Haoxuan , Gao Haoji , Ye Feng , Zhang Yaqi , Peng Yi , Liang Juyong , Jiang Yimei , Zhang Tao , Qiu Weihua , Lu Xin , Zhao Ren
Published: January 2019

ETS transcription factors play important roles in tumor cell invasion, differentiation and angiogenesis. In this study, we initially demonstrated that ETS translocation variant 5 (ETV5) is abnormally upregulated in colorectal cancer (CRC), is positively correlated with CRC tumor size, lymphatic metastasis and tumor node metastasis (TNM) stage and indicates shorter survival and disease‐free survival in CRC patients. In vitro and in vivo experiments revealed that the downregulation of ETV5 could significantly suppress CRC cell proliferation. Moreover, overexpression of ETV5 could stimulate CRC angiogenesis in vitro and in vivo, which is consistent with RNA‐seq results. Then, we identified platelet‐derived growth factor BB (PDGF‐BB) as a direct target of ETV5 that plays an important role in ETV5‐mediated CRC angiogenesis through an angiogenesis antibody microarray. Additionally, PDGF‐BB could activate VEGFA expression via the PDGFR‐β/Src/STAT3 pathway in CRC cells and appeared to be positively correlated with ETV5 in CRC tissues. Finally, we revealed that ETV5 could bind directly to the promoter region of PDGF‐BB and regulate its expression through ChIP and luciferase assays. Overall, our study suggested that the transcription factor ETV5 could stimulate CRC malignancy and promote CRC angiogenesis by directly targeting PDGF‐BB. These findings suggest that EVT5 may be a potential new diagnostic and prognostic marker in CRC and that targeting ETV5 might be a potential therapeutic option for inhibiting CRC angiogenesis.
Knockdown of TRIM27 expression suppresses the dysfunction of mesangial cells in lupus nephritis by FoxO1 pathway
Authors: Liu Jinxi , Feng Xiaojuan , Tian Yu , Wang Kexin , Gao Fan , Yang Lin , Li Hongbo , Tian Yuexin , Yang Ran , Zhao lu , Miao Xinyan , Huang Jie , Liu Qingjuan , Zhang Wei , Li Yuzhe , Wang Chunlin , Duan Huijun , Liu Shuxia
Published: January 2019

TRIM27 (tripartite motif‐containing 27) is a member of the TRIM (tripartite motif) protein family and participates in a variety of biological processes. Some research has reported that TRIM27 was highly expressed in certain kinds of carcinoma cells and tissues and played an important role in the proliferation of carcinoma cells. However, whether TRIM27 takes part in the progression of lupus nephritis (LN) especially in cells proliferation remains unclear. Our study revealed that the overexpression of TRIM27 was observed in the kidneys of patients with LN, lupus mice and mesangial cells exposed to LN plasma which correlated with the proliferation of mesangial cells and ECM (extracellular matrix) deposition. Downregulation of TRIM27 expression suppressed the proliferation of mesangial cells and ECM accumulation in MRL/lpr mice and cultured human mesangial cells (HMCs) by regulating the FoxO1 pathway. Furthermore, the overexpression of FoxO1 remarkably decreased HMCs proliferation level and ECM accumulation in LN plasma‐treated HMCs. In addition, the protein kinase B (Akt) signal pathway inhibitor LY294002 significantly reduced the expression of TRIM27 and inhibited the dysfunction of mesangial cells. These above data suggested that TRIM27 mediated abnormal mesangial cell proliferation in kidney of lupus and might be the potential target for treating mesangial cell proliferation of lupus nephritis.
Differential regulation of vacuolar H+‐ATPase subunits by transforming growth factor‐β1 in salivary ducts
Authors: Kluge Milena , Namkoong Eun , Khakipoor Shokoufeh , Park Kyungpyo , Roussa Eleni
Published: January 2019

Bicarbonate concentration in saliva is controlled by the action of acid–base transporters in salivary duct cells. We show for the first time expression of ATP6V1B1 in submandibular gland and introduce transforming growth factor‐beta (TGF‐β) as a novel regulator of V‐ATPase subunits. Using QRT‐PCR, immunoblotting, biotinylation of surface proteins, immunofluorescence, chromatin immunoprecipitation, and intracellular H(+) recording with H(+)‐sensitive dye 2′,7′‐bis‐(carboxyethyl)‐5‐(and‐6)‐carboxyfluorescein we show that in the human submandibular gland (HSG) cell line, activation of TGF‐β signaling upregulates ATP6V1E1 and ATP6V1B2, downregulates ATP6V1B1, and has no effect on ATP6V1A. TGF‐β1 effects on ATP6V1B1 are mediated through the canonical, the soluble adenylate cyclase, and ERK signaling. A CREB binding sequence was identified in the ATP6V1B1 promoter and CREB binding decreased after TGF‐β1 treatment. Following acidosis, a bafilomycin‐sensitive and Na+‐independent cell pH recovery was observed in HSG cells, an effect that was not influenced after disruption of acidic lysosomes. Moreover, neutralization of TGF‐βs, inhibition of TGF‐β receptor, or inhibition of the canonical pathway decreased membrane expression of ATP6V1A and prevented the acidosis‐induced increased V‐ATPase activity. The results suggest multiple modes of action of TGF‐β1 on V‐ATPase subunits in HSG cells: TGF‐β1 may regulate transcription or protein synthesis of certain subunits and trafficking of other subunits in a context‐dependent manner. Moreover, surface V‐ATPase is active in salivary duct cells and involved in intracellular pH regulation following acidosis.
An Alternative Approach to the Synthesis of Parvistone C
Authors: Addada Ramakrishnam Raju , Regalla Venkata Reddy , Gangireddy Venkata Sivarami Reddy , Vema Venkata Naresh , Anna Venkateswara Rao
Published: January 2019

A stereoselective total synthesis of parvistone C, an oxygenated natural styryllactone, has been accomplished in excellent overall yield by employing asymmetric aldol reaction, asymmetric epoxidation and regioselective epoxide ring opening as the key steps. Our synthetic strategy is very simple, concise and no use of protecting groups.
Dissociation pathways of protic ionic liquid clusters: Alkylammonium nitrates
Authors: Patrick Amanda L. , Annesley Christopher J.
Published: January 2019

Protic ionic liquids are promising candidates for many applications, including as spacecraft propellants. For both fundamental interest and understanding clustering and dissociation during electrospray‐based propulsion, it is useful to explore the dissociation pathways of protic ionic liquid clusters, as well as the factors affecting the relative contributions of each pathway to the observed MS/MS spectra. With that said, most of the published reports on ionic liquid cluster dissociation have focused on aprotic ionic liquids. The purpose of the current work is to explore the dissociation pathways (eg, loss of amine, nitric acid, or ion pair) of alkylammonium nitrates using energy‐resolved collision‐induced dissociation. Here, it was found that, in general, protic ionic liquids have multiple dissociation pathways—namely, protic ionic liquids can lose their neutralized cation (here, an alkylamine) or neutralized anion (here, nitric acid)—in addition to the ion pair dissociation familiar to aprotic salt and aprotic ionic liquid clusters. In general, increasing the basicity of the cation (here, through increasing the degree of alkylation) decreases the propensity to follow these alternative pathways. Interestingly, increasing the cluster size has a similar effect: as cluster size increases, nitric acid loss decreases. These results will help better model and design protic ionic liquids for electrospray‐based spacecraft propulsion and help provide a better understanding for the general behavior of protic ionic liquids versus aprotic ionic liquids within mass spectrometers.
Hydralazine derivative of aldehyde: A new type of [M − H]+ ion formed in electrospray ionization mass spectrometry
Authors: Xiao Hua‐Ming , Wang Xian , Yang Xing , Zheng Feng , Feng Yu‐Qi
Published: January 2019

Hydralazine has been widely employed in the development of drugs, derivatization reagents, and ligands. In the present work, we reported a new type of dehydrogenated ion [M − H]+ that was produced from the hydralazine derivative of hexanal in electrospray ionization mass spectrometry (ESI‐MS). The formation of [M − H]+ ions in the ESI‐MS was found to be independent on the mobile phase composition of the liquid chromatography and ESI source parameters. A series of hydralazine derivatives of aldehyde were investigated to confirm this phenomenon. The results showed that hydralazine derivatives of aldehydes that contained an sp3 hybridization carbon with a hydrogen at the α‐position of aldehydes could form the unexpected [M − H]+ ions, whereas hydralazine derivative of acetone could only generate [M + H]+ ion in the ESI‐MS. We proposed the possible formation mechanism of [M − H]+ ion for the hydralazine derivatives of aldehydes: the [M − H]+ ion was possibly formed by the loss a hydrogen molecule (H2) from the protonated ion [M + H]+. The results obtained from density functional theory (DFT) calculations supported this proposed formation mechanism of [M − H]+ ion.
Are servant leaders appreciated? An investigation of how relational attributions influence employee feelings of gratitude and prosocial behaviors
Authors: Sun Jiaqing , Liden Robert C. , Ouyang Linyi
Published: January 2019

Multisource data collected at three time phases were used in investigating when servant leadership elicits gratitude and then promotes prosocial behaviors. We tested a moderated mediation model, contending that relational attributions moderate the relationship between servant leadership and gratitude, and then gratitude sequentially predicts interpersonal citizenship behaviors and upward voice. As hypothesized, when employees do not highly rely on relational attributions for servant leadership, they feel more gratitude and subsequently engage in more interpersonal citizenship behaviors and upward voice than the employees who rely on relational attributions to explain their interactions with the leader. The sequential indirect effect from servant leadership to upward voice via gratitude and then interpersonal citizenship behaviors was significant when relational attributions are low rather than high.
Carnoy's solution fixation with compression significantly increases the number of lymph nodes yielded from colorectal cancer specimens
Authors: Flynn Sean M. , Burchette Raoul J. , Ghassemi Majid , Ratner Oleg , Mandel Danielle , Tomassi Marco J. , Klaristenfeld Daniel D.
Published: January 2019

Background and Objectives

Carnoy's fixation and compression represents a novel technique to enhance lymph node evaluation and accuracy of staging after colorectal cancer resection.

Methods

This study was performed in all adults undergoing colorectal cancer operations by Kaiser Permanente surgeons at two separate facilities. Patients were assigned to either location based upon surgeon and patient availability. One group of patients had their lymph nodes examined with current standard manual technique (MT). The other group had their specimens fixed with Carnoy's solution and then compressed (CT) to assess for lymph nodes.

Results

A total of 157 patients were enrolled. Seventy‐eight patient specimens underwent MT and 79 patient specimens underwent the new compression technique (CT). CT resulted in a significant increase in total lymph node yield per specimen (37.6 ± 18.5 nodes with CT vs 18.9 ± 8.8 nodes with MT; P < 0.0001). CT also resulted in sufficient lymph node sampling (>12 nodes) in all 79 patients in the group compared with 13 of 78 patients (17%) with an insufficient lymph node evaluation in the MT group (
P = 0.0002).

Conclusion

This study demonstrated that Carnoy's fixation with compression can significantly increase lymph node yields in colorectal cancer specimens and allow for a higher rate of adequate lymph node sampling.
Correlation between serum prealbumin and prognosis of patients with hepatocellular carcinoma after hepatectomy
Authors: Jia Rong‐Rong , Zhong Jian‐Hong , Huo Rong‐Rui , Su Qi‐Bin , Xiang Xiao , Zhao Fu‐Lin , Qin Zhong‐Bian , Chen Jia‐Hao , Liao Ying‐Yang , Ma Liang , Xiang Bang‐De , Zhang Chun‐Yan , Li Le‐Qun
Published: January 2019

Objective

To determine whether serum prealbumin levels are associated with long‐term survival after hepatectomy in patients with primary hepatocellular carcinoma(HCC).

Methods

A consecutive sample of 526 patients with HCC who underwent potentially curative hepatectomy from August 2007 to August 2010 was retrospectively analyzed. Patients were classified as having normal or reduced serum prealbumin based on cut‐off values of 200 or 182 mg/L.

Results

Multivariate analysis identified the preoperative level of serum prealbumin as an independent prognostic factor of long‐term survival (P < 0.05): Survival was significantly better for those with normal levels than for those with reduced levels, based on either cut‐off value. Similar results were observed in subgroup analyses based on the degree of cirrhosis, level of ɑ‐fetoprotein and Barcelona Clinic Liver Cancer stage.

Conclusions

Preoperative level of serum prealbumin may be useful for predicting long‐term survival in patients with HCC after hepatectomy.
Rare metastatic patterns after malignant transformation of serous borderline tumor of the ovary
Authors: Siemon John , Nguyen Dao M , Pinto Andre , Schlumbrecht Matthew
Published: January 2019

Serous borderline tumors are rare, benign ovarian neoplasms that may recur and undergo malignant transformation to low‐grade serous carcinomas (LGSCs). In this report, a 50‐year‐old female with a remote history of a serous borderline ovarian tumor experienced a recurrence of LGSC, presenting as a large solitary subcutaneous mass anterior to the sternum after a 33‐year disease‐free interval. The described case highlights the unpredictable nature of this disease and the importance of implementing lifelong surveillance strategies.
Highly Controllable Lasing Actions in Lead Halide Perovskite–Si3N4 Hybrid Micro‐Resonators
Authors: Huang Can , Sun Wenzhao , Liu Shuai , Li Shuai , Wang Shuai , Wang Yujie , Zhang Nan , Fu Hongbing , Xiao Shumin , Song Qinghai
Published: January 2019

Lead halide perovskite (MAPbX3) nanosheets are promising materials for optoelectronic devices. However, as the as‐grown perovskite nanosheets typically have random sizes, positions, and alignments, their device performances are hard to be controlled and repeated, significantly hindering the practical applications in nanophotonics. Herein, a novel approach to realize highly controllable lasing actions in MAPbX3 nanosheets is demonstrated. By hybridizing the perovskite with an Si3N4 wafer, it is shown that the cavity shape and the internal lasing actions are precisely controllable via the patterns in Si3N4 wafer, which is pre‐defined with mature CMOS technique and will not spoil the exceptional gain of perovskite nanosheet. Consequently, whispering gallery mode (WGM) micro‐lasers with well‐controlled mode numbers, mode spacing, repeatability, directionalities, and even internal angular momentum are experimentally realized. In addition, by constructing coupled micro‐structures, the proximity effects between WGM lasers are also explored. This research provides a substrate‐control mechanism to precisely define and control MAPbX3 perovskite micro‐lasers.
Identifying initial condition of the Rayleigh‐Stokes problem with random noise
Authors: Nguyen Hoang Luc , Nguyen Huy Tuan , Mokhtar Kirane , Duong Dang Xuan Thanh
Published: January 2019

We investigate a backward problem for the Rayleigh‐Stokes problem, which aims to determine the initial status of some physical field such as temperature for slow diffusion from its present measurement data. This problem is well‐known to be ill‐posed because of the rapid decay of the forward process. We construct a regularized solution using the filter regularization method in the Gaussian random noise. Under some a priori assumptions on the exact solution, we establish the expectation between the exact solution and the regularized solution in the L2 and Hm norms.
One LTE LB and two conjoined LTE M/HB MIMO antennas with a compact symmetric frame structure at the short edge of the metal‐framed smartphone
Authors: Wong Kin‐Lu , Lin Song‐En , Barani Imee Ristika Rahmi , Li Wei‐Yu
Published: January 2019

The metal‐frame long‐term evolution (LTE) antennas with a compact symmetric frame structure at the short edge of the metal‐framed smartphone are presented. The proposed metal‐frame antennas cover the LTE low band (LB) in 824~960 MHz and two LTE middle/high bands (M/HBs) in 1710~2690 MHz. The LTE LB antenna uses a short metal‐frame section of 41.8 mm (about 0.12 wavelength at 824 MHz). The two LTE M/HB antennas together use a continuous metal‐frame section of 41.8 mm (about 0.24 wavelength at 1710 MHz), same as the LTE LB antenna. The two LTE M/HB antennas show low envelope correlation coefficient (ECC) of <0.1 in 1710~2690 MHz, owing to using a capacitor‐loaded shorting strip for the two antennas conjoined to achieve a compact and decoupled structure. The low ECC allows the two LTE M/HB antennas to be promising for 2 × 2 multi‐input multi‐output operation.
Approximation capabilities of immersed finite element spaces for elasticity Interface problems
Authors: Guo Ruchi , Lin Tao , Lin Yanping
Published: January 2019

We construct and analyze a group of immersed finite element (IFE) spaces formed by linear, bilinear, and rotated Q1 polynomials for solving planar elasticity equation involving interface. The shape functions in these IFE spaces are constructed through a group of approximate jump conditions such that the unisolvence of the bilinear and rotated Q1 IFE shape functions are always guaranteed regardless of the Lamé parameters and the interface location. The boundedness property and a group of identities of the proposed IFE shape functions are established. A multi‐point Taylor expansion is utilized to show the optimal approximation capabilities for the proposed IFE spaces through the Lagrange type interpolation operators.
Electronic Defects in Amorphous Oxide Semiconductors: A Review
Authors: Ide Keisuke , Nomura Kenji , Hosono Hideo , Kamiya Toshio
Published: January 2019

Amorphous oxide semiconductors (AOSs) have been commercialized since 2012 as thin‐film transistor (TFT) backplanes in flat‐panel displays. This review first provides a brief history and current status of AOS technology, and then introduces electronic defects in AOSs reported to date that are critically important for understanding and controlling the instability of TFTs that is the most serious issue in the development of the AOS technology. In particular, it is important to know that many AOS defects are related to oxygen and hydrogen impurities, though oxygen is the major constituent of AOS and hydrogen is not intentionally incorporated. Instability issues and their underlying mechanisms are also discussed in relation to these defects.
Pneumatically driven surgical instrument capable of estimating translational force and grasping force
Authors: Miyazaki Ryoken , Kanno Takahiro , Kawashima Kenji
Published: January 2019

Background: In robot‐assisted minimally invasive surgery, feedback as well as sensing of translational and grasping forces allows surgeons to manipulate the robots using an appropriate force. However, there have been limited reports on single instruments capable of sensing both forces (translational force and grasping force), with the exception of instruments with electronic sensors.

Methods: In this study, a pneumatically driven surgical instrument capable of estimating both translational and grasping forces is developed. Our estimation method is based on the dynamics and pneumatic pressure changes of the instrument. For each force estimation, we applied a joint mechanism consisting of disks and a flexible backbone and constructed pneumatic driving systems, kinematic models, dynamic models, controller, and force estimator.

Results: We confirmed experimentally that the mean absolute error between the measured forces and the estimated translational and grasping forces is 0.2 N or less for any condition. From these results, it is seen that the mechanical interference between the joint actuation mechanism and grasper actuation mechanism is negligibly small.

Conclusions: A method for estimating both forces was proposed, and experimental results confirmed the effectiveness of the method.
Robust adaptive tracking control for a class of mechanical systems with unknown disturbances under actuator saturation
Authors: Hu Xin , Wei Xinjiang , Zhang Huifeng , Han Jian , Liu Xiuhua
Published: January 2019

A robust adaptive tracking control scheme is presented for a class of multiple‐input and multiple‐output mechanical systems with unknown disturbances under actuator saturation. The unknown disturbances are expressed as the outputs of a linear exogenous system with unknown coefficient matrices. An adaptive disturbance observer is constructed for the online disturbance estimation. An actuator saturation compensator is introduced to attenuate the adverse effects of actuator saturation. The adaptive backstepping method is then applied to design the robust adaptive tracking control law. It is proved that the designed control law makes the system outputs track the desired trajectories and guarantees the global uniform ultimate stability of the closed‐loop control system. Simulations on a two‐link robotic manipulator verify the effectiveness of the proposed control scheme.
Enumeration and randomized constructions of hypertrees
Authors: Linial Nati , Peled Yuval
Published: January 2019

Over 30 years ago, Kalai proved a beautiful d‐dimensional analog of Cayley's formula for the number of n‐vertex trees. He enumerated d‐dimensional hypertrees weighted by the squared size of their (d − 1)‐dimensional homology group. This, however, does not answer the more basic problem of unweighted enumeration of d‐hypertrees, which is our concern here. Our main result, Theorem 1.4, significantly improves the lower bound for the number of d‐hypertrees. In addition, we study a random 1‐out model of d‐complexes where every (d − 1)‐dimensional face selects a random d‐face containing it, and show that it has a negligible d‐dimensional homology.
Facet‐Dependent Optical Properties of Semiconductor Nanocrystals
Authors: Huang Michael H.
Published: January 2019

Recent observations of facet‐dependent electrical conductivity and photocatalytic activity of various semiconductor crystals are presented. Then, the discovery of facet‐dependent surface plasmon resonance absorption of metal–Cu2O core–shell nanocrystals with tunable sizes and shapes is discussed. The Cu2O shells also exhibit a facet‐specific optical absorption feature. The facet‐dependent electrical conductivity, photocatalytic activity, and optical properties are related phenomena, resulting from the presence of an ultrathin surface layer with different band structures and thus varying degrees of band bending for the {100}, {110}, and {111} faces of Cu2O to absorb light of somewhat different wavelengths. Recently, it is shown that the light absorption and photoluminescence properties of pure Cu2O cubes, octahedra, and rhombic dodecahedra also display size and facet effects because of their tunable band gaps. A modified band diagram of Cu2O can be constructed to incorporate these optical effects. Literature also provides examples of facet‐dependent optical behaviors of semiconductor nanostructures, indicating that optical properties of nanoscale semiconductor materials are intrinsically facet‐dependent. Some applications of semiconductor optical size and facet effects are considered.
The rise and fall of green growth: Korea's energy sector experiment and its lessons for sustainable energy policy
Authors: Ha Yoon‐Hee , Byrne John
Published: January 2019

The idea of “green growth” has received international attention for more than a decade as a promising solution to a distinctly modern problem: a century of unparalleled increases in wealth based on equally unparalleled innovations in energy technology accompanied by global environmental threats such as climate change and persistent socioeconomic inequality. The green growth premise is that this problem can be solved without surrendering continued economic growth by a redirection of human effort to invent green energy technology, green energy markets, and green energy choice. Proponents have argued that green‐energy based economic growth represents a paradigm shift bringing forth sustainable and equitable relations between environment, economy, and society. The paper reviews a decade of green energy growth strategies and practices. The Korean Green Growth Initiative (KGGI) is investigated as a case study of green energy growth operationalization. Korea’s experiment was widely hailed by international bodies such as The Organization for Economic Cooperation and Development (OECD) and United Nations Department of Economic and Social Affairs (UNDESA) for its bold attempt at paradigm shift, with the hope that, if it succeeded, countries currently on the periphery of modern development would be able to overcome conditions of poverty, environmental degradation, and political dependency. But our analysis of the Korean case questions the idea and ideology of green energy growth, demonstrating instead that KGGI was quickly coopted by the paradigm it was supposed to supplant. In this respect, one contradiction in the strategy and practice of green energy growth has been its promise to change the trajectory of modern development without requiring serious changes in modern values and ideology.

This article is categorized under:

Energy and Climate > Economics and Policy

Energy and Development > Climate and Environment

Energy and Development > Economics and Policy
Social Inequality, Childhood and the Media
Authors: Paus-Hasebrink Ingrid , Kulterer Jasmin , Sinner Philip
Published: January 2019

This chapter of this book deals with the connections between social inequality, childhood and media. The first part is dedicated to national contexts of social inequality and to a discussion of social disadvantage in rich Western societies, with the specific examples of Austria and Germany. The second part deals with the connection between inequality and mediatization. One central argument is that a disadvantageous position in a mediatised society often leads to a lack of participation in society (education, job perspectives and so on). In our mediatised Western societies, participation is closely connected to (digital) media, so that socialisation often becomes media socialisation. We will preface a survey of relevant trends in global mediatization with a literature review covering the evidence of the links between social disadvantages and media experiences. To conclude, we will discuss the consequences of mediatization for academic research on young people’s growing up in general and for our study on media socialisation among socially disadvantaged adolescents in particular.
The Role of Media Within Young People’s Socialisation: A Theoretical Approach
Authors: Paus-Hasebrink Ingrid , Kulterer Jasmin , Sinner Philip
Published: January 2019

The study is based on a praxeological research perspective on the processes involved in the media socialisation of children and adolescents. It treats the socialisation as a dynamic and interlinked process acting on both the individual child and the relevant social contexts. Our approach is, therefore, focused on the lifeworld of a child in the family, where everyday life happens and where, most importantly, media activity is already being endowed with meaning in early childhood. This approach to media socialisation allows researchers to understand the subjective nature of a child’s media practices (providing a link to his/her family), as well as his/heroptions for action,outlines for action, andcompetences for action. Using these three central analytical concepts, the role of the media, against the backdrop of socio-structural conditions, becomes understandable, in as far as it relates to the interlinkage of subjective perceptions, orientations motivating action and everyday life practices.