bluuebunny/crossref_metadata_2025_split huggingface dataset:
RNA interference of carboxyesterases causes nymph mortality in the Asian citrus psyllid, Diaphorina citri
Authors: Kishk Abdelaziz , Anber Helmy A. I. , AbdEl‐Raof Tsamoh K. , El‐Sherbeni AbdEl‐Hakeem D. , Hamed Sobhy , Gowda Siddarame , Killiny Nabil 
Published: February 2017

AbstractAsian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is an important pest of citrus. In addition, D. citri is the vector of Huanglongbing, a destructive disease in citrus, also known as citrus greening disease caused by Candidatus Liberibacter asiaticus. Huanglongbing causes huge losses for citrus industries. Insecticide application for D. citri is the major strategy to prevent disease spread. The heavy use of insecticides causes development of insecticide resistance. We used RNA interference (RNAi) to silence genes implicated in pesticide resistance in order to increase the susceptibility. The activity of dsRNA to reduce the expression of carboxyesterases including esterases FE4 (EstFE4) and acetylcholinesterases (AChe) in D. citri was investigated. The dsRNA was applied topically to the fourth and fifth instars of nymphs. We targeted several EstFE4 and AChe genes using dsRNA against a consensus sequence for each of them. Five concentrations (25, 50, 75, 100, 125 ng/μl) from both dsRNAs were used. The treatments with the dsRNA caused concentration dependent nymph mortality. The highest gene expression levels of both AChe and EstFE4 were found in the fourth and fifth nymphal instars. Gene expression analysis showed that AChe genes were downregulated in emerged adults from dsRNA‐AChe‐treated nymphs compared to controls. However, EstFE4 genes were not affected. In the same manner, treatment with dsRNA‐EstFE4 reduced expression level of EstFE4 genes in emerged adults from treated nymphs, but did not affect the expression of AChe genes. In the era of environmentally friendly control strategies, RNAi is a new promising venue to reduce pesticide applications.
A new approach in stem cell research—Exosomes: Their mechanism of action via cellular pathways
Authors: Derkus Burak , Emregul Kaan C. , Emregul Emel 
Published: February 2017

AbstractExosomes are nano‐sized vesicles surrounded by a lipid membrane, which tend to be secreted toward extra‐cellular environments. Despite being defined as vesicles involved in excretion of molecular wastes by Rose Johnstone in the 1970s, further studies revealed them to be effective in various biological processes such as cancer development, regulation of the immune system, intercellular communication, stem cell biology, and tissue/organ regeneration. Although many studies dealing with the role of exosomes in stem cell differentiation and the use of exosomes isolated from stem cells for the treatment of several diseases have been published, the involved mechanisms remain largely unknown. Further understanding of these mechanisms, which include the involved cellular pathways, may improve the use of exosomes in diagnostic and treatment methods, especially for those involving stem cells. Here, we describe some recent data describing the action mechanism of stem cell‐derived exosomes focusing on the implicated cellular pathways, hoping to provide novel information that will be useful for cell biology scientists working in this field.
Risk stratification of periprocedural myocardial infarction after percutaneous coronary intervention: Analysis based on the SCAI definition
Authors: Zhang Dong , Li Yiping , Yin Dong , He Yuan , Chen Changzhe , Song Chenxi , Yan Ruohua , Zhu Chen'gang , Xu Bo , Dou Kefei 
Published: February 2017

ObjectivesTo investigate the predictors of and generate a risk prediction method for periprocedural myocardial infarction (PMI) after percutaneous coronary intervention (PCI) using the new PMI definition proposed by the Society for Cardiovascular Angiography and Interventions (SCAI).BackgroundThe SCAI‐defined PMI was found to be associated with worse prognosis than the PMI diagnosed by other definitions. However, few large‐sample studies have attempted to predict the risk of SCAI‐defined PMI.MethodsA total of 3,371 patients (3,516 selective PCIs) were included in this single‐center retrospective analysis. The diagnostic criteria for PMI were set according to the SCAI definition. All clinical characteristics, coronary angiography findings and PCI procedural factors were collected. Multivariate logistic regression analysis was performed to identify independent predictors of PMI. To evaluate the risk of PMI, a multivariable risk score (PMI score) was constructed with incremental weights attributed to each component variable according to their estimated coefficients.ResultsPMI occurred in 108 (3.1%) of all patients. Age, multivessel treatment, at least one bifurcation treatment and total treated lesion length were independent predictors of SCAI‐defined PMI. PMI scores ranged from 0 to 20. The C‐statistic of PMI score was 0.71 (95% confidence interval: 0.66–0.76). PMI rates increased significantly from 1.96% in the non‐high‐risk group (PMI score < 10) to 6.26% in the high‐risk group (PMI score ≥ 10) (P < 0.001).ConclusionsAge, multivessel treatment, at least one bifurcation treatment, and total treated lesion length are predictive of PMI. The PMI score could help identify patients at high risk of PMI after PCI. © 2017 Wiley Periodicals, Inc.
The Birth of Nickel Phosphide Catalysts: Monitoring Phosphorus Insertion into Nickel
Authors: Carenco Sophie , Liu Zhi , Salmeron Miquel 
Published: February 2017

AbstractTri‐n‐octylphosphine (TOP) is used widely as a phosphorating agent to yield metal phosphide nanocatalysts, which are receiving intense attention because of their high performance in both electrochemical and hydrotreatment catalytic processes, such as the hydrogen evolution reaction and the hydrodesulfurization reaction. We used in situ ambient‐pressure X‐ray photoelectron spectroscopy to investigate the formation of nickel phosphide on the surface of a nickel foil at temperatures close to those employed to form nickel phosphide nanoparticles in the colloidal route. We showed that the onset of phosphorus insertion into nickel occurs at as low as 150 °C, which is much lower than that reported previously (>210 °C). Moreover, the formation of sp2 carbon was observed on the surface as the consequence of TOP alkyl chain decomposition. These findings provide new insights into the surface chemistry of metal phosphide nanoparticles, which are increasingly employed in several fields of catalysis. Our results demonstrate that even below 150 °C, significant phosphorus and carbon incorporation can occur during metal nanoparticle syntheses if TOP is employed as the stabilizing agent.
Role of Caesium in Higher Alcohol Synthesis over Modified Copper–Cobalt Nanocomposites under Mild Conditions
Authors: Das Subhasis , Sengupta Manideepa , Bordoloi Ankur 
Published: February 2017

AbstractCu–Co nanocomposites with and without Cs promoter on a modified lanthanum–alumina support were prepared by the combination of two unique synthesis methods. The synthesized materials were exclusively characterized by means of XRD, BET surface area determination, H2 temperature‐programmed reduction, CO2 temperature‐programmed desorption, N2O frontal chromatography, X‐ray photoelectron spectroscopy, high‐resolution TEM, and elemental mapping techniques, and its catalytic properties were thoroughly investigated for the selective synthesis of higher alcohols in the CO hydrogenation reaction by using a H2/CO ratio of 1, a temperature range of 180–300 °C and a pressure variation of 15–60 bar. Cs incorporation and a Cu/Co ratio of three was found to be a very efficient combination to obtain alcohol selectivities up to 55 %. This was explained by the fact that Cs increases the surface area of Cu particles by migrating Cu towards the surface layer and strengthens the surface interaction of Cu and Co. The further increase in higher alcohols selectivity then results from the limited formation of methane and carbon dioxide.
Preparation of 3D Reduced Graphene Oxide/MnO2 Nanocomposites through a Vacuum‐Impregnation Method and Their Electrochemical Capacitive Behavior
Authors: Zhong Jie , Yi Fenyun , Gao Aimei , Shu Dong , Huang Yulan , Li Zhibo , Zhu Weilie , He Chun , Meng Tao , Zhao Shixu 
Published: February 2017

AbstractIn this work, three‐dimensional (3D) porous reduced graphene oxide (rGO) is prepared by means of a microwave‐hydrothermal method, and then MnO2 is introduced in situ and anchored into the pores of the 3D‐rGO through a novel vacuum‐impregnation method to obtain the 3D‐rGO/MnO2 nanocomposite. SEM images show the honeycomb structure of the 3D‐rGO/MnO2, and MnO2 is tightly anchored on the surface and into the pores of 3D‐rGO. 3D‐rGO/MnO2 nanocomposite electrodes display excellent electrochemical capacitive behavior, owing to the synergetic effect between the porous 3D‐rGO with high conductivity and MnO2 with high theoretical capacitance. The 3D‐rGO/MnO2‐5 sample, with an optimum MnO2 content of (53.1%), gives the highest specific capacitance (278.5 F g−1 at 1 A g−1) and good rate capability. This sample also has remarkable cycling stability (93.5% capacitance retention after 10000 cycles). The 3D‐rGO/MnO2 nanocomposite could be considered as a potential candidate for supercapacitor electrode materials.
Preparation and Electrochemical Properties of High‐Voltage Spinel LiNi0.5Mn1.5O4 Synthesized by using Different Manganese Sources
Authors: Liu Yang , Lu Zhongpei , Deng Chenfang , Xu Wei , Hu Tao , Yan Bo , Yang Gang 
Published: February 2017

AbstractThe crystal structure and electrochemical performance of the 4.7 V cathode LiNi0.5Mn1.5O4 (LNMO) are quite dependent on the amount of Mn3+ and ordering of Ni/Mn in the octahedral sites. This work attempts to study LNMO synthesized by using different manganese sources, in which the valence states of manganese are +2, +2/+3, +3 and +4. A small amount of Mn3+ existing in the spinel crystal structures of the obtained LNMO can dramatically affect the material's conductivity and electrochemical performance. Among the four studied samples, LNMO‐1 (with MnCO3 as the manganese source) delivers the highest specific capacity of 138 mAh g−1, higher than LNMO‐2 (Mn3O4 as the manganese source), LNMO‐3 (Mn2O3 as the manganese source), and LNMO‐4 (MnO2 as the manganese source). After 100 cycles at 0.2 C, LNMO‐1 still delivers the highest discharge capacity of 129 mAh g−1. This work provides an insight into the phenomenon of how manganese sources influence the lithium diffusion ability and crystal structure stability of LNMO as a cathode material for highly reversible lithium storage.
Assessment of Cooperativity in Ternary Peptide‐Cucurbit[8]uril Complexes
Authors: Cavatorta Emanuela , Jonkheijm Pascal , Huskens Jurriaan 
Published: February 2017

AbstractEvaluating cooperativity for cucurbit[8]uril (CB[8])‐mediated ternary complexation is required for understanding and advancing designs of such ternary self‐assembled systems. A key issue is to dissect the contributions of the binding steps of the first and second guest molecules to the overall ternary complex formation energy. This is addressed by performing concentration‐dependent titrations between CB[8] and guests by means of concentration‐dependent calorimetric and 1H‐NMR titrations. The sensitivity of the fitting of the cumulative heat of complexation of the calorimetric titrations is evaluated in terms of fitting error and enthalpy–entropy compensation and, together with the NMR spectroscopic analysis of the separate species, non‐cooperative binding is conceived to be the most probable binding scenario. The binding behavior of CB[8] homoternary complexes is similar to CB[8] heteroternary complexes, with an enthalpy‐driven tight fit of the guests in the CB[8] cavity overcoming the entropic penalty. Also for these types of complexes, a non‐cooperative binding is the most probable.
Silver‐Mediated Base Pairs in DNA Incorporating Purines, 7‐Deazapurines, and 8‐Aza‐7‐deazapurines: Impact of Reduced Nucleobase Binding Sites and an Altered Glycosylation Position
Authors: Zhao Hang , Leonard Peter , Guo Xiurong , Yang Haozhe , Seela Frank 
Published: February 2017

AbstractFormation of silver‐mediated DNA was studied with oligonucleotides incorporating 8‐aza‐7‐deazapurine, 7‐deazapurine, and purine nucleosides. The investigation was performed on non‐self‐complementary duplexes with one or two modifications and self‐complementary duplexes with an alternating dA–dT motif. Homo base pairs as well as base pair mismatches of dA analogues with dC and Watson–Crick pairs with dT were studied by stoichiometric silver ion titration and Tm measurements. N8‐Glycosylated 8‐aza‐7‐deazaadenine forms silver‐ion‐mediated base pairs capturing two silver ions (low silver content) whereas regularly glycosylated 8‐aza‐7‐deazapurine, 7‐deazapurine (c7Ad), and dA do not form comparable structures. Stable silver‐mediated “dA–dC” base pair mismatches were detected for all nucleosides. Two silver ions per base pair are bound by 8‐aza‐7‐deazapurine whereas c7Ad binds only one silver ion. The situation is different when the equivalents of silver ions were increased to the number of total base pairs. Surprisingly, in 12‐mer duplexes as well as in related 25‐mer duplexes every base pair consumed one silver ion.
Development of Polar Order by Liquid‐Crystal Self‐Assembly of Weakly Bent Molecules
Authors: Alaasar Mohamed , Prehm Marko , Poppe Silvio , Tschierske Carsten 
Published: February 2017

AbstractOrganic ferroelectrics are of growing importance for multifunctional materials. Here we provide an understanding of the distinct stages of the development of sterically induced polar order in liquid‐crystalline (LC) soft matter. Three series of weakly bent molecules derived from 4‐cyanoresorcinol as the bent core unit with laterally fluorinated azobenzene wings have been synthesized, and the effects of the position of fluorine substitution, alkyl‐chain length, and temperature on the LC self‐assembly and polar order were studied. In the LC phases a paraelectric–ferroelectric transition took place as the size of the polar domains gradually increased, thereby crossing a permittivity maximum, similar to inorganic solid‐state ferroelectrics. An increase in polar coherence length simultaneously led to a transition from synpolar to antipolar domain correlation in the high‐permittivity paraelectric range. Associated with the emergence of polar order was the development of a tilted organization of the molecules and a growing coherence of tilt. This led to a transition from non‐tilted via tilt‐randomized uniaxial to long‐range‐tilted biaxial smectic phases, and to surface‐stabilized symmetry breaking with the formation of chiral conglomerates and field‐induced tilt. Moreover, there is a remarkably strong effect of the position of fluorination; polar order is favored by peripheral core substitution and is suppressed by inside‐directed fluorination.
Near‐Infrared Light and pH Dual‐Responsive Targeted Drug Carrier Based on Core‐Crosslinked Polyaniline Nanoparticles for Intracellular Delivery of Cisplatin
Authors: You Chaoqun , Wu Hongshuai , Wang Minxing , Zhang Yawen , Wang Jingwen , Luo Yanghui , Zhai Lihai , Sun Baiwang , Zhang Xiangyang , Zhu Jin 
Published: February 2017

AbstractBiodegradable polymeric nanoparticles have received growing interest as one of the most promising agents for drug delivery. In the present work, functional and core‐crosslinked poly(ethylene glycol) with poly(ϵ‐caprolactone) (PEG5k‐PCL10k) block copolymer and lecithin as biodegradable polymer doped with polyaniline was used to assemble nanoparticles which were prepared for targeted delivery and controlled release of cisplatin. The morphology of the polyaniline nanoparticles was determined by dynamic light scattering and the prepared nanoparticles showed a size of 83(±1) nm and a uniform spherical shape. For targeting to HER2 receptors, Herceptin was applied to guide the nanoparticles to breast cancer cells. Studies on cellular uptake and drug release of the nanocarriers showed that the prepared nanoparticles were efficiently taken up by breast cancer cells and the drug was released efficiently under acidic conditions when exposed to a near‐infrared laser (808 nm, 1.54 W) for 5 min. Our research highlights the great potential of near‐infrared light and pH dual‐responsive release by core‐crosslinked nanoparticles in nanobiomedicine.
Robust Ti‐ and Zr‐Based Metal‐Organic Frameworks for Photocatalysis
Authors: Sun Dengrong , Li Zhaohui 
Published: February 2017

AbstractPhotocatalysis represents a promising pathway for the direct conversion of solar energy to valuable chemical energy. Metal‐organic frameworks (MOFs), which are constructed from metal/metal clusters interconnected with organic ligands, have recently emerged as a promising candidate in this field. Among various MOFs, Ti‐ and Zr‐based MOFs have gained intensive interest in photocatalysis due to their relation to the commonly used photocatalyst (TiO2) and high stability. In this review, we summarized the recent applications of Ti‐ and Zr‐based MOFs in solar fuel production, including water reduction and oxidation, CO2 reduction and organics syntheses. Strategies to improve the MOF‐based photocatalysis via improving their light absorption and facilitate the charge separation were also demonstrated. Finally, opportunities and challenges facing the MOFs‐based photocatalysis, especially the Ti‐ and Zr containing MOFs were addressed.
Synthesis of Mesoporous (Ga1−xZnx)(N1−xOx) Using Layered Double Hydroxides as Precursors for Enhanced Visible‐Light Driven H2 Production
Authors: Li Xuedong , Zhang Qinghong , Wang Hongzhi , Li Yaogang 
Published: February 2017

AbstractMesoporous (Ga1−xZnx)(N1−xOx) hexagonal nanoplates were prepared by nitridation of layered double hydroxides (LDHs) containing Zn2+ and Ga3+ ions with different [Zn]/[Ga] ratios. Their specific surface areas ranged from 21.25 to 50.95 m2/g were much higher than those previously reported. The (Ga1−xZnx)(N1−xOx) showed broad visible light absorption and reduced band gaps with increasing Zn content. When [Zn]/[Ga] = 2, the (Ga1−xZnx)(N1−xOx) absorbed strongly the light of wavelength less than 525 nm and showed the highest visible light driven H2 production efficiency. After totally repeated runs for 30 h, the H2‐production activity of (Ga1−xZnx)(N1−xOx) did not fall off, indicating its good photochemical stability and photocatalytic activity for long time. Herein, the results provide new insights into (Ga1−xZnx)(N1−xOx) as high performance photocatalyst and their potential application in visible‐light driven water splitting H2 production.
The clinical utility of normal findings on noninvasive cardiac assessment in the prediction of atrial fibrillation
Authors: Venkatesh Sanjay , O'Neal Wesley T. , Broughton Stephen T. , Shah Amit J. , Soliman Elsayed Z. 
Published: February 2017

BackgroundThe absence of abnormalities on noninvasive cardiac assessment possibly confers a reduced risk of atrial fibrillation (AF) despite the presence of traditional risk factors.HypothesisNormal findings on noninvasive cardiac assessment are associated with a lower risk of AF development.MethodsWe examined the clinical utility of normal findings on routine noninvasive cardiac assessment in 5331 participants (85% white; 57% women) from the Cardiovascular Health Study who were free of baseline AF. The combination of a normal electrocardiogram (ECG) + normal echocardiogram was assessed for the development of AF events. A normal ECG was defined as the absence of major or minor Minnesota code abnormalities. A normal echocardiogram was defined as the absence of contractile dysfunction, wall motion abnormalities, or abnormal left ventricular mass. Cox regression was used to compute the 10‐year risk of developing AF.ResultsDuring the 10‐year study period, a total of 951 (18%) AF events were detected. A normal ECG (multivariable hazard ratio [HR]: 0.80, 95% confidence interval [CI]: 0.69‐0.92) and normal echocardiogram (multivariable HR: 0.75, 95% CI: 0.65‐0.87) were associated with a reduced risk of AF in isolation. This association improved in those with normal ECG + normal echocardiogram (multivariable HR: 0.66, 95% CI: 0.55‐0.79) compared with participants who had abnormal ECG + abnormal echocardiogram (referent).ConclusionsNormal findings on routine noninvasive cardiac assessment identify persons in whom the risk of AF is low. Further studies are needed to explore the utility of this profile regarding the decision to implement certain risk factor modification strategies in older adults to reduce AF burden.
Intracardiac echocardiography for verification for left atrial appendage thrombus presence detected by transesophageal echocardiography: the ActionICE II study
Authors: Baran Jakub , Zaborska Beata , Piotrowski Roman , Sikora‐Frąc Malgorzata , Pilichowska‐Paszkiet Ewa , Kułakowski Piotr 
Published: February 2017

BackgroundTransesophageal echocardiography (TEE) remains the gold standard for exclusion of left atrial appendage (LAA) thrombus in patients scheduled for direct electrical cardioversion (DEC) or atrial fibrillation (AF) ablation. Recently, intracardiac echocardiography (ICE) of the pulmonary artery (PA) has been shown to provide excellent LAA images and to be useful in verification of equivocal TEE findings.Hypothesis
ICE of the PA may have a role in detecting false‐positive TEE results.MethodsTwenty‐one patients (12 male, age 65 ± 8 years, CHADS2VASC2 score [congestive heart failure, hypertension, age ≥ 75, age 65‐74, diabetes mellitus, stroke/TIA/thrombo‐embolism, vascular disease, sex female] = 2.2; HAS‐BLED score [hypertension, abnormal renal and liver function, stroke, bleeding, labile International Normalized Ratio, elderly, drugs or alcohol] = 1.1), in whom a thrombus in the LAA was detected during TEE before DEC or AF ablation, underwent ICE of the PA.ResultsOn TEE, in 7 (33%) patients, the LAA thrombus was described as “solid” and in the remaining 14 (67%) as “soft.” Disagreement between the TEE and ICE (thrombus in TEE and no thrombus in ICE) was found in 9 (43%) patients. In the solid thrombus group, ICE confirmed thrombi existence in 6 and excluded thrombi in 1 patient. In the soft thrombus group, ICE confirmed thrombi in 6 patients and excluded thrombi in the remaining 8 patients. Of the demographic and clinical variables, only the longstanding persistent type of AF was significantly associated with the presence of an LAA thrombus detected both by TEE and ICE.ConclusionsWith TEE, a false positive of an LAA thrombus may be indicated, especially when a thrombus is described as soft rather than solid. Our study suggests that ICE may be a valuable option for verification of a TEE‐based diagnosis of a thrombus.