bluuebunny/crossref_metadata_2025 huggingface dataset:
The Dynamic Nature of CO Adlayers on Pt(111) Electrodes
Authors: Wei Jie , Amirbeigiarab Reihaneh , Chen Yan‐Xia , Sakong Sung , Gross Axel , Magnussen Olaf M.
Published: January 2020

CO adlayers on Pt(111) electrode surfaces are an important electrochemical system and of great relevance to electrocatalysis. The potential‐dependent structure and dynamics of these adlayers are complex and still controversial, especially in the CO pre‐oxidation regime. We here employ in situ high‐speed scanning tunneling microscopy for studying the surface phase behavior in CO‐saturated 0.1 m H2SO4 on the millisecond time scale. At potentials near the onset of CO pre‐oxidation local fluctuations in the (2×2)‐CO adlayer are observed, which increase towards more positive potentials. Above 0.20 V (vs. Ag/AgCl), this leads to an adlayer where COad apparently reside on every top site, but still exhibit a (2×2) superstructure modulation. We interpret this observation as a dynamic effect, caused by a small number of highly mobile point defects in the (2×2)‐CO adlayer. As shown by density functional theory calculations, the CO lattice near such defects relaxes into a local (1×1) arrangement, which can rapidly propagate across the surface. This scenario, where a static (2×2) COad sublattice coexists with a highly dynamic sublattice of partially occupied top sites, explains the pronounced COad surface mobility during electrooxidation.
Aldolase Cascade Facilitated by Self‐Assembled Nanotubes from Short Peptide Amphiphiles
Authors: Reja Antara , Afrose Syed Pavel , Das Dibyendu
Published: January 2020

Early evolution benefited from a complex network of reactions involving multiple C−C bond forming and breaking events that were critical for primitive metabolism. Nature gradually chose highly evolved and complex enzymes such as lyases to efficiently facilitate C−C bond formation and cleavage with remarkable substrate selectivity. Reported here is a lipidated short peptide which accesses a homogenous nanotubular morphology to efficiently catalyze C−C bond cleavage and formation. This system shows morphology‐dependent catalytic rates, suggesting the formation of a binding pocket and registered enhancements in the presence of the hydrogen‐bond donor tyrosine, which is exploited by extant aldolases. These assemblies showed excellent substrate selectivity and templated the formation of a specific adduct from a pool of possible adducts. The ability to catalyze metabolically relevant cascade transformations suggests the importance of such systems in early evolution.
Photocontrolled Synthesis of n‐Type Conjugated Polymers
Authors: Woods Eliot F. , Berl Alexandra J. , Kalow Julia A.
Published: January 2020

Current approaches to synthesize π‐conjugated polymers (CPs) are dominated by thermally driven, transition‐metal‐mediated reactions. Herein we show that electron‐deficient Grignard monomers readily polymerize under visible‐light irradiation at room temperature in the absence of a catalyst. The product distribution can be tuned by the wavelength of irradiation based on the absorption of the polymer. Conversion studies are consistent with an uncontrolled chain‐growth process; correspondingly, chain extension produces all‐conjugated n‐type block copolymers. Preliminary results demonstrate that the polymerization can be expanded to donor–acceptor alternating copolymers. We anticipate that this method can serve as a platform to access new architectures of n‐type CPs without the need for transition‐metal catalysis.
Transfer Hydrogenation of Nitroarenes Catalyzed by CoCu Anchored on Nitrogen‐doped Porous Carbon
Authors: Liu Xiaotong , Zhang Longkang , Wang Junmin , Shang Ningzhao , Gao Shutao , Wang Chun , Gao Yongjun
Published: January 2020

The non‐precious metal catalysts with high catalytic activity is extremely desirable but still full of challenges. In this paper, CoCu bimetal immobilized on nitrogen‐doped porous carbon (CoCu‐N‐C) was prepared by an effective ligand‐stabilized pyrolysis strategy. CoCu‐N‐C exhibited excellent catalytic efficiency for the transfer hydrogenation of nitroarenes with ammonia borane as hydrogen source, which can be ascribed to the well dispersed metal nanoparticles, the synergetic interaction of CoCu bimetal and nitrogen‐doped carbon. The durability and recyclability experiments of the recycled CoCu‐N‐C catalyst indicated that no obvious change in catalytic performance was observed after five consecutive cycles. To gain insight into the catalytic mechanism of CoCu‐N‐C for the hydrogenation reaction, density functional theory calculations was also conducted. This work provides an universal approach for constructing highly efficient non‐precious metal heterogeneous catalysts and which may find diverse high performance applications.
The chloro‐substituent enhances performance of 2,4‐bis (imino)pyridylchromium catalysts yielding highly linear polyethylene
Authors: Gansukh Badral , Zhang Qiuyue , Flisak Zygmunt , Liang Tongling , Ma Yanping , Sun Wen‐Hua
Published: January 2020

The five unsymmetrical 2‐[1‐(2,4‐dibenzhydryl‐6‐chlorophenylimino)ethyl]‐6‐[1‐(arylimino)ethyl]pyridine compounds (aryl: 2,6‐Me2Ph L1, 2,6‐Et2Ph L2, 2,6‐iPr2Ph L3, 2,4,6‐Me3Ph L4 and 2,6‐Et2–4‐MePh L5) were prepared and characterized with FT‐IR and 1H/13C NMR spectroscopy as well as elemental analysis. The treatment of L1 – L5 with CrCl3·3THF affords the corresponding chromium chloride complexes (Cr1 – Cr5) in excellent yields. The molecular structures of Cr2 and Cr3 characterized by X‐ray diffraction show a distorted octahedral geometry with three nitrogen atoms and three chlorine atoms around the metal center. On activation with either MAO or MMAO, Cr1 – Cr5 collectively display high activity (up to 14.96 × 106 g (PE) mol−1 (Cr) h−1 at 60 °C) affording highly linear polyethylene with low molecular weight distribution (Mw/Mn) ranging from 1.06 to 2.81. An in‐depth catalytic evaluation of Cr1 was conducted in order to investigate how the cocatalyst type and its amount, reaction temperature and polymerization time affect the catalytic activities and polymer properties.
Decoration of silver nanoparticles on multi‐walled carbon nanotubes: Investigation of its anti‐acute leukemia property against acute myeloid leukemia and acute T cell leukemia
Authors: Shahriari Maryam , Hemmati Saba , Zangeneh Akram , Zangeneh Mohammad Mahdi
Published: January 2020

Recently, the development of carbon nanocomposites composed of carbon nanotubes and metal nanoparticles has attracted many interests because of their large potential for technological applications such as catalysts, sensors, biomedicine, and disinfection. In the present study, we described a simple chemistry method to synthesize multi‐walled carbon nanotubes (MWCNTs) decorated with silver nanoparticles (Ag‐NPs). Also, we investigated the antioxidant and anti‐acute leukemia activities against acute myeloid leukemia and acute T cell leukemia cell lines. Ag NPs‐MWCNTs were characterized and analyzed using common nanotechnology techniques including transmission electron microscopy (TEM), X‐ray diffraction (XRD), energy dispersive X‐ray spectroscopy (EDS), field emission‐scanning electron microscopy (FE‐SEM) and elemental mapping analysis. Also, 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) test was performed to assess the antioxidant capacities of AgNO3, MWCNTs, and Ag NPs‐MWCNTs. It revealed similar antioxidant potentials for Ag NPs‐MWCNTs and butylated hydroxytoluene. In MTT assay, Ag NPs‐MWCNTs had very low cell viability (very high anti‐acute leukemia properties) dose‐dependently against 32D‐FLT3‐ITD (Acute myeloid leukemia cell line), Human HL‐60/vcr (Acute myeloid leukemia cell line), Jurkat, Clone E6–1 (Acute T cell leukemia cell line), and J.RT3‐T3.5 (Acute T cell leukemia cell line) without any cytotoxicity on human umbilical vein endothelial cell line (HUVEC; Normal cell line). In conclusion, the synthesized Ag NPs‐MWCNTs revealed excellent antioxidant and cytotoxicity activities against acute myeloid leukemia and acute T cell leukemia cell lines in a dose depended manner. After confirming in thein vivoand clinical trials, these nanoparticles can be administrated in humans for the treatment of acute leukemia especially acute myeloid leukemia and acute T cell leukemia.
Solid‐phase extraction materials based on molecularly imprinted polymers for recognition of pyrethroids
Authors: Guo Ting , Zhou Hongyuan , Yu Yong , Dai Hongjie , Zhang Yuhao , Ma Liang
Published: January 2020

A novel recognition material for detection of kinds of pyrethroids was successfully synthesized by molecular imprinting technology. 3‐Phenoxybenzoic acid (PBA) usually could be the antigen to prepare the polyclonal antibody. In this work, the recognition material was prepared utilizing PBA as the template, methacrylicacid as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. The recognition material was characterized by atomic force microscope, adsorption equilibrium and selectivity experiments. The results showed that the recognition material has been successfully prepared and recognized four pyrethroids (fenpropathrin, deltamethrin, fenvalerate, and cyhalothrin). The recognition material was utilized as sorbents in solid‐phase extraction for separation and detection of pyrethroids in practically samples. Under the optimal conditions, the recoveries were ranging from 74.3 to 111.0%. Therefore, novel materials for pyrethroids are very promising for future applications. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48919.
Brain‐derived neurotrophic factor and Glial cell line‐derived neurotrophic factor expressions in the trigeminal root entry zone and trigeminal ganglion neurons of a trigeminal neuralgia rat model
Authors: Luo Daoshu , Luo Lili , Lin Ren , Lin Ling , Lin Qing
Published: January 2020

Microvascular compression on the trigeminal root entry zone (TREZ) is the main etiology of trigeminal neuralgia (TN) patients. To investigate brain‐derived neurotrophic factor (BDNF) and glial cell line‐derived neurotrophic factor (GDNF) in the trigeminal ganglion (TG) and TREZ, immunofluorescence staining and Western blot were used in a rat TN model. Both BDNF and GDNF were observed in the TG neurons and TREZ. The expression of the BDNF dimer in the TG was increased in the TN group, while GDNF expression was decreased after compression injury. The BDNF dimer/pro‐BDNF ratio in the TREZ of the TN group was higher than that in the sham group, but the GDNF expression in the TREZ was significantly lower than that in the sham group. These results suggested that compression injury in the TREZ of rats induced dynamic changes in BDNF and GDNF in both the TG and TREZ, and these changes are involved in the nociceptive transmission of the TN animal model.
Triclosan treatment to pregnant albino rats affects offspring numbers and the liver of both the pregnant rats and their offspring, and these effects are ameliorated by co‐treatment with bee honey
Authors: Hanafy Safaa M. , Abo‐Ouf Amany M. , Mohamed Amany F. , Arafa Mona A. A. , Shawky Lamiaa M.
Published: January 2020

We have assessed the effects of the broad‐spectrum bactericide triclosan on the liver of pregnant albino rats and their offspring, and evaluated the protective potential of bee honey, which has radical‐scavenging properties. The study involved treatment of 72 pregnant rats followed by examination of the pregnant rats and their offspring. The pregnant rats were divided equally into six groups (I–VI), each of which was subdivided equally into two Subgroups (A and B). Rats in the A subgroups were gavaged with a daily dose of 1.26 ml distilled water (IA), 1 ml corn oil (IIA), 1.68 ml aqueous solution of Clover Blossom honey (IIIA), 0.3 mg triclosan (IVA), 13 mg triclosan (VA), or 1.68 ml aqueous solution of honey with 13 mg triclosan (VIA), throughout pregnancy. Rats in the B subgroups received the same treatments throughout pregnancy and for 14 days after delivery. At the end of the experiments, the offspring's numbers were recorded and blood samples were taken from the pregnant rats for analysis. The livers of the studied groups were subjected for; histological study, morphometric analysis, and biochemical estimation of markers of oxidative stress. The results showed that the acceptable daily intake of triclosan did not induce significant pathological changes in the liver while high dose of triclosan induced pathological changes in the livers and reduced the numbers of offspring. Co‐administration of honey with triclosan ameliorated most pathological change. Therefore, decrease the exposure of the pregnant women to triclosan is encouraged or co‐supplementation with bee honey if exposure could not be avoided.
Emission Control by Molecular Manipulation of Double‐Paddled Binuclear PtII Complexes at the Air‐Water Interface
Authors: Adachi Junya , Mori Taizo , Inoue Ryo , Naito Masaya , Le Ngoc Ha‐Thu , Kawamorita Soichiro , Hill Jonathan P. , Naota Takeshi , Ariga Katsuhiko
Published: January 2020

Molecular functions depend on conformations and motions of the corresponding molecular species. An air–water interface is a suitable asymmetric field for the control of molecular conformations and motions under a small applied force. In this work, double‐paddled binuclear PtII complexes containing pyrazole rings linked by alkyl spacers were synthesized and their orientations and emission properties dynamically manipulated at the air–water interface. The complexes emerge from water with concurrent variation of interface orientation of the planes of the PtII complexes from perpendicular to parallel during mechanical compression suggesting a unique ‘submarine emission‘. Phosphorescence of the complexes is quenched at the air–water interface prior to monolayer formation with intensities subsequently rapidly increasing during monolayer compression. These results indicate that asymmetric reactions and motions might be controlled by applying mechanical force at the air–water interface.
Using a Heme‐Based Nanozyme as Bifunctional Redox Mediator for Li−O2 Batteries
Authors: Mu Xiaowei , Liu Yufeng , Zhang Xueping , Wei Hui , He Ping , Zhou Haoshen
Published: January 2020

The realization of practical aprotic Li−O2 batteries is hindered by superoxide‐related parasitic reactions and high overpotentials. Herein, a heme‐based nanozyme containing iron‐porphyrin derivative ligands is used as a novel electrolyte additive to scavenge superoxide radicals in the Li−O2 system. Specially, this type of nanozyme can act as a bifunctional catalyst for both discharge and charge by coordinating with superoxide intermediates, functioning as a molecular shuttle of superoxide species and electrons between cathodes and products. As a consequence, the Li−O2 batteries exhibit boosted discharge capacity, reduced charge polarization and superior cycling stability in the presence of the nanozyme additive. This first attempt to using nanozyme in Li−O2 batteries should pave a new way for the sustainable cross‐link between biomimetic enzymes and advanced energy storage.
Multiple imputation methods for handling incomplete longitudinal and clustered data where the target analysis is a linear mixed effects model
Authors: Huque Md Hamidul , Moreno‐Betancur Margarita , Quartagno Matteo , Simpson Julie A. , Carlin John B. , Lee Katherine J.
Published: January 2020

Multiple imputation (MI) is increasingly popular for handling multivariate missing data. Two general approaches are available in standard computer packages: MI based on the posterior distribution of incomplete variables under a multivariate (joint) model, and fully conditional specification (FCS), which imputes missing values using univariate conditional distributions for each incomplete variable given all the others, cycling iteratively through the univariate imputation models. In the context of longitudinal or clustered data, it is not clear whether these approaches result in consistent estimates of regression coefficient and variance component parameters when the analysis model of interest is a linear mixed effects model (LMM) that includes both random intercepts and slopes with either covariates or both covariates and outcome contain missing information. In the current paper, we compared the performance of seven different MI methods for handling missing values in longitudinal and clustered data in the context of fitting LMMs with both random intercepts and slopes. We study the theoretical compatibility between specific imputation models fitted under each of these approaches and the LMM, and also conduct simulation studies in both the longitudinal and clustered data settings. Simulations were motivated by analyses of the association between body mass index (BMI) and quality of life (QoL) in the Longitudinal Study of Australian Children (LSAC). Our findings showed that the relative performance of MI methods vary according to whether the incomplete covariate has fixed or random effects and whether there is missingnesss in the outcome variable. We showed that compatible imputation and analysis models resulted in consistent estimation of both regression parameters and variance components via simulation. We illustrate our findings with the analysis of LSAC data.
Surgeons' posture and muscle strain during laparoscopic and robotic surgery
Authors: Dalager T , Jensen P T , Eriksen J R , Jakobsen H L , Mogensen O , Søgaard K
Published: January 2020

Background

It is assumed that conventional laparoscopy (LAP) and robotic-assisted laparoscopic surgery (RALS) differ in terms of the surgeon's comfort. This study compared muscle workload, work posture and perceived physical exertion of surgeons performing LAP or RALS.

Methods

Colorectal surgeons with experience in advanced LAP and RALS performed one of each operation. Bipolar surface electromyography (EMG) recordings were made from forearm, shoulder and neck muscles, and expressed relative to EMG maximum (%EMGmax). The static, median and peak levels of muscle activity were calculated, and an exposure variation analysis undertaken. Postural observations were carried out every 10 min, and ratings of perceived physical exertion before and after surgery were recorded.

Results

The study included 13 surgeons. Surgeons performing LAP showed higher static, median, and peak forearm muscle activity than those undertaking RALS. Muscle activity at peak level was higher during RALS than LAP. Exposure variation analysis demonstrated long-lasting periods of low-level intensity muscle activity in the shoulders for LAP, in the forearms for RALS, and in the neck for both procedures. Postural observations revealed a greater need for a change in work posture when performing LAP compared with RALS. Perceived physical exertion was no different between the surgical modalities.

Conclusion

Minimally invasive surgery requires long-term static muscle activity with a high physical workload for surgeons. RALS is less demanding on posture.
Pharmacokinetic effects of ginsenoside Rg1 on aconitine, benzoylaconine and aconine by UHPLC–MS/MS
Authors: Xu Yanwen , Yang Liang , Liang Kun , An Rui , Wang Xinhong , Zhang Hai
Published: January 2020

Ginseng and aconite are well‐known couplet medicinals. Ginsenoside Rg1 is the main active ingredient in ginseng, and aconitine (AC), benzoylaconine (BAC) and aconine (ACN) are three representative alkaloids in aconite, which belong to the diester alkaloids, monoester alkaloids and alkanolamine alkaloids respectively. The aim of this study was to investigate the pharmacokinetic effects of ginsenoside Rg1 on the three types of alkaloids and to provide evidences for their compatibility mechanism. In this study, the ginsenoside Rg1 was simultaneously intragastrically administered to rats with AC, BAC and ACN, respectively, and the rat plasma was collected at different time points. The plasma drug concentrations of the three types of alkaloids were determined by UHPLC–MS/MS, and the pharmacokinetic parameters were calculated. The results indicated that the peak concentration and area under the concentration–time curve of BAC were significantly increased (P < 0.05), those for AC were decreased (P < 0.05), and the values for ACN did not change after pretreatment with ginsenoside Rg1. It was inferred that ginsenoside Rg1 may affect the absorption and metabolism of AC and BAC and then change their pharmacokinetic parameters. Subsequently, their absorption and metabolism were further investigated using the Caco‐2 cell monolayer and rat liver microsomes in vitro. The Caco‐2 cell monolayer absorption assay indicated that ginsenoside Rg1 could promote the absorption of AC and BAC, and the rat liver microsomes metabolism assay indicated that ginsenoside Rg1 accelerated the metabolism of AC and did not affect the other two alkaloids. All of the results indicated that ginsenoside Rg1 may reduce the toxicity of aconite and improve its efficacy by promoting the absorption of BAC and accelerating the metabolism of AC. These results could provide evidence for the compatibility mechanism of the traditional Chinese herbal formula Shenfu Decoction.
Is the environment‐friendly factor attractive to customers when purchasing electric vehicles? Evidence from South Korea
Authors: Beak Yujin , Kim Kayoung , Maeng Kyuho , Cho Youngsang
Published: January 2020

In a bid to reduce greenhouse gas emissions, several countries worldwide are implementing policies to promote electric vehicles (EVs). However, contrary to expectations, the diffusion speed of EVs has been rather slow in South Korea. This study analyzes consumer preferences for the technological and environmental attributes of EVs and derives policy and environmental implications to promote market diffusion of EVs in South Korea. We conduct a choice‐based conjoint survey of 1,008 consumers in South Korea and estimate the consumer utility function using a mixed logit model considering consumer heterogeneity. Based on the consumer utility function, we analyze consumers' willingness‐to‐pay (WTP) for EV attributes such as driving range, charging method, charging time, autonomous driving function, carbon dioxide (CO2) reduction rate, and purchase price. The results indicate that the current low acceptance of EVs is due to their relatively high price and lack of a battery charging technology that satisfies consumers' expectations of the charging method and time. One interesting finding is that Korean consumers have a relatively higher WTP for the CO2 reduction rate of EVs than consumers in other countries; however, they do not consider CO2 reduction over other technological attributes when choosing EVs. This implies that the rate of CO2 reduction of EVs is not an important factor for South Korean consumers when buying EVs. We also calculate the effect of CO2 reduction with the market penetration of EVs and find that CO2 reduction through the diffusion of EVs depends on the country's electricity generation mix.
Consider insider's view of learning from controversy
Authors: McCarthy Claudine
Published: January 2020

CLEARWATER, FLA. — Understanding how leaders on your campus view and manage controversy may help your office bring key questions of campus safety to the forefront in a timely manner.
A Modified Arrhenius Approach to Thermodynamically Study Regioselectivity in Cytochrome P450‐Catalyzed Substrate Conversion
Authors: Luirink Rosa A. , Verkade‐Vreeker Marlies C. A. , Commandeur Jan N. M. , Geerke Daan P.
Published: January 2020

The regio‐ (and stereo‐)selectivity and specific activity of cytochrome P450s are determined by the accessibility of potential sites of metabolism (SOMs) of the bound substrate relative to the heme, and the activation barrier of the regioselective oxidation reaction(s). The accessibility of potential SOMs depends on the relative binding free energy (ΔΔGbind) of the catalytically active substrate‐binding poses, and the probability of the substrate to adopt a transition‐state geometry. An established experimental method to measure activation energies of enzymatic reactions is the analysis of reaction rate constants at different temperatures and the construction of Arrhenius plots. This is a challenge for multistep P450‐catalyzed processes that involve redox partners. We introduce a modified Arrhenius approach to overcome the limitations in studying P450 selectivity, which can be applied in multiproduct enzyme catalysis. Our approach gives combined information on relative activation energies, ΔΔGbind values, and collision entropies, yielding direct insight into the basis of selectivity in substrate conversion.
Late clinical outcomes of myocardial hybrid revascularization versus coronary artery bypass grafting for complex triple‐vessel disease: Long‐term follow‐up of the randomized MERGING clinical trial
Authors: Esteves Vinicius , Oliveira Marco A. P. , Feitosa Fernanda S. , Mariani José , Campos Carlos M. , Hajjar Ludhmila A. , Lisboa Luiz A. , Jatene Fabio B. , Filho Roberto K. , Lemos Neto Pedro A.
Published: January 2020

Objectives

This article aimed to compare the outcomes after hybrid revascularization with conventional coronary artery bypass grafting (CABG) surgery.

Background

The concept of hybrid coronary revascularization combines the advantages of CABG and percutaneous coronary intervention to improve the treatment of patients with complex multivessel disease.

Methods

The Myocardial hybrid revascularization versus coronary artERy bypass GraftING for complex triple‐vessel disease—MERGING study is a pilot randomized trial that allocated 60 patients with complex triple‐vessel disease to treatment with hybrid revascularization or conventional CABG (2:1 ratio). The primary outcome was the composite of all‐cause death, myocardial infarction, stroke, or unplanned repeat revascularization at 2 years.

Results

Clinical and anatomical characteristics were similar between groups. After a mean follow‐up of 802 ± 500 days, the primary endpoint rate was 19.3% in the hybrid arm and 5.9% in the CABG arm (p = NS). The incidence of unplanned revascularization increased over time in both groups, reaching 14.5 versus 5.9% in the hybrid and in the CABG groups, respectively (p = .4). Of note, in the hybrid group, there were no reinterventions driven by the occurrence of stent restenosis.

Conclusions

Hybrid myocardial was feasible but associated with increasing rates of major adverse cardiovascular events during 2 years of clinical follow‐up, while the control group treated with conventional surgery presented with low rates of complications during the same period. In conclusion, before more definitive data arise, hybrid revascularization should be applied with careful attention in practice, following a selective case‐by‐case indication.
Transcatheter closure of coronary artery fistula: A 21‐year experience
Authors: El‐Sabawi Bassim , Al‐Hijji Mohammed A. , Eleid Mackram F. , Cabalka Allison K. , Ammash Naser M. , Dearani Joseph A. , Bjarnason Haraldur , Holmes David R. , Rihal Charanjit S.
Published: January 2020

Objectives

To evaluate the outcomes of transcatheter coronary artery fistula (CAF) closure and to identify anatomic/procedural factors that may impact outcomes.

Background

Due to the rarity of CAF, reported experience with transcatheter closure remains limited and anatomic and procedural factors that may lead to unsuccessful closure, complications, or recanalization of CAF are unclear.

Methods

All patients who underwent transcatheter CAF closure at Mayo Clinic from 1997 to 2018 were retrospectively reviewed. CAF anatomic characteristics, procedural techniques, and clinical/angiographic outcomes were assessed.

Results

A total of 45 patients underwent transcatheter closure of 56 CAFs. The most commonly used devices were embolization coils in 40 (71.4%) CAFs, vascular occluders in 10 (17.8%), or covered stent in 2 (3.6%). Acute procedural success with no or trivial residual flow occurred in 50 (89.3%) CAFs. Residual flow was small in three (5.4%) and large in three (5.4%). Eight (17.8%) patients had complications, including device migration in three, intracranial hemorrhage from anticoagulation in one, and myocardial infarction (MI) in four. MI was a result of covered stent thrombosis or stagnation of flow after closure of large distal CAF. Twenty‐two patients with 27 CAFs had follow‐up angiography after successful index procedure at median time of 423 (IQ 97‐1348) days. Of these, 23 (85.2%) had no/trace flow and 4 had large flow from recanalization.

Conclusions

Transcatheter CAF closure is associated with a favorable acute procedural success and complication rate in selected patients. Procedural success and risk for complication are highly dependent on CAF anatomy and closure technique.
Electroless Nanoplating of Pd−Pt Alloy Nanotube Networks: Catalysts with Full Compositional Control for the Methanol Oxidation Reaction
Authors: Stohr Tobias , Fischer Angelina , Muench Falk , Antoni Markus , Wollstadt Stephan , Lohaus Christian , Kunz Ulrike , Clemens Oliver , Klein Andreas , Ensinger Wolfgang
Published: January 2020

Due to its simplicity, flexibility and conformity, electroless plating presents itself as an attractive route towards functional metal nanostructures. Despite the importance for creating multimetallic materials with enhanced properties, the complex interactions between the components in electroless plating baths make alloy formations a challenging objective. In this work, we outline an electroless plating strategy fabricating Pd−Pt alloy nanomaterials, which is based on arbitrarily miscible plating baths for the individual metals. To demonstrate the excellent nanoscale conformity and homogeneity of our plating system, we apply it to ion track‐etched polymer templates with large inner surfaces as ambitious substrates, resulting in the formation of 3D free‐standing PdxPt100‐x‐nanotube‐networks (NTNWs). Based on the electro‐oxidation of methanol as a model reaction, we utilize the compositional freedom provided by our syntheses for optimizing the catalytic performance of our metal NTNWs, which heavily depends on the Pd−Pt ratio. Within our system, the highest surface normalized activity was found for the Pd20Pt80 NTNW, reaching more than a two‐fold increase of the peak current density in comparison to pure Pt. Overall, our reaction system provides a versatile toolkit for fabricating intricate Pd−Pt nanostructures of arbitrary elemental composition, and constitutes a starting point for designing new electroless alloy plating baths.
Magnetism and Afterglow United: Synthesis of Novel Double Core–Shell Eu2+‐Doped Bifunctional Nanoparticles
Authors: Terraschke Huayna , Franzreb Matthias , Wickleder Claudia
Published: January 2020

Afterglow–magnetic nanoparticles (NPs) offer enormous potential for bioimaging applications, as they can be manipulated by a magnetic field, as well as emitting light after irradiation with an excitation source, thus distinguishing themselves from fluorescent living cells. In this work, a novel double core–shell strategy is presented, uniting co‐precipitation with combustion synthesis routes to combine an Fe3O4 magnetic core (≈15 nm) with an afterglow SrAl2O4:Eu2+,Dy3+ outer coat (≈10 nm), and applying a SiO2 protective middle layer (≈16 nm) to reduce the luminescence quenching caused by the Fe core ions. The resulting Fe3O4@SiO2@SrAl2O4:Eu2+,Dy3+ NPs emit green light attributed to the 4f65d1→4f7(8S7/2) transition of Eu2+ under UV radiation and for a few seconds afterwards. This bifunctional nanocomposite can potentially be applied for the detection and separation of cells or diagnostically relevant molecules.
pH‐Dependent Hydration Change in a Gd‐Based MRI Contrast Agent with a Phosphonated Ligand
Authors: Charpentier Cyrille , Salaam Jérémy , Nonat Aline , Carniato Fabio , Jeannin Olivier , Brandariz Isabel , Esteban‐Gomez David , Platas‐Iglesias Carlos , Charbonnière Loïc J. , Botta Mauro
Published: January 2020

The heptadentate ligand L was shown to form an extremely stable Gd complex at neutral pH with a pGd value of 18.4 at pH 7.4. The X‐ray crystal structures of the complexes formed with Gd and Tb displayed two very different coordination behaviors being, respectively, octa‐ and nonacoordinated. The relaxometric properties of the Gd complex were studied by field‐dependent relaxivity measurements at various temperatures and by 17O NMR spectroscopy. The pH‐dependence of the longitudinal relaxivity profile indicated large changes around neutral pH leading to a very large value of 10.1 mm−1⋅s−1 (60 MHz, 298 K) at pH 4.7. The changes were attributed to an increase of the hydration number from one water molecule in basic conditions to two at acidic pH. A similar trend was observed for the luminescence of the Eu complex, confirming the change in hydration state. DOSY experiments were performed on the Lu analogue, pointing to the absence of dimers in solution in the considered pH range. A breathing mode of the complex was postulated, which was further supported by 1H and 31P NMR spectroscopy of the Yb complex at varying pH and was finally modeled by DFT calculations.
Sodium Bicyclo[1.1.1]pentanesulfinate: A Bench‐Stable Precursor for Bicyclo[1.1.1]pentylsulfones and Bicyclo‐ [1.1.1]pentanesulfonamides
Authors: Bär Robin M. , Gross Patrick J. , Nieger Martin , Bräse Stefan
Published: January 2020

Herein, we present the synthesis of the bench‐stable sodium bicyclo[1.1.1]pentanesulfinate (BCP‐SO2Na) and its application in the synthesis of bicyclo[1.1.1]pentyl (BCP) sulfones and sulfonamides. The salt can be obtained in a four‐step procedure from commercially available precursors in multigram scale without the need for column chromatography or crystallization. Sulfinates are known to be useful precursors in radical and nucleophilic reactions and are widely used in medicinal chemistry. This building block enables access to BCP sulfones and sulfonamides avoiding the volatile [1.1.1]propellane which is favorable for the extension of SAR studies. Further, BCP‐SO2Na enables the synthesis of products that were not available with previous methods. A chlorination of BCP‐SO2Na and subsequent reaction with a Grignard reagent provides a new route to BCP sulfoxides. Several products were analyzed by single‐crystal X‐ray diffraction.
Experimental study on the influence of the orifice size on hydrodynamic characteristics and bubble size distribution of an external loop airlift reactor
Authors: Lu Xia , Zheng Xiaotao , Ding Yigang , Lin Wei , Wang Wei , Yu Jiuyang
Published: January 2020

The orifice size has a significant influence on hydrodynamic characteristics and bubble size distribution (BSD) in gas‐liquid flow. However, the mechanism of the influence of orifice size on BSD and hydrodynamic characteristics in an external loop airlift reactor (EL‐ALR) has not been fully revealed. In this work, the effects of the orifice size on hydrodynamic characteristics and BSD in a laboratory scale EL‐ALR were investigated using the particle image velocimetry (PIV) technique and digital image analysis (DIA). The results show that the transition superficial gas velocity becomes greater when the orifice size is reduced. The time‐averaged bubble velocity profiles along the riser radius are parabolic, and the shape of the time‐averaged bubble velocity curve is strongly dependent on the orifice diameter. The larger the orifice diameter, the steeper the parabolas. For sparger with lager orifice diameters, the BSD curve is bimodal even at low superficial gas velocity, and its peaks shift to a larger equivalent bubble diameter. The bubble aspect ratio appears to be related only to the equivalent diameter of the bubbles, regardless of the diameter of the orifice. It has a defined relationship between the bubble aspect ratio and the bubble equivalent diameter, and a new correlation is obtained based on the experimental data. This study will help to gain an understanding of the influence of sparger orifice size on the hydrodynamic characteristics and BSD and provide a basis for numerical simulation.
Metal‐Organic Sheets for Efficient Drug Delivery and Bioimaging
Authors: Song Yucong , Yang Jingjie , Wang Lei , Xie Zhigang
Published: January 2020

Metal‐organic frameworks (MOFs) formed by coordination between metal ions or clusters and organic bridging ligands possess great potential for biomedicine applications, given their high biocompatibility and biodegradability. Compared with the traditional three‐dimensional (3D) MOFs, two‐dimensional (2D) MOFs with sheet‐like morphologies exhibit unique properties. In this study, a nanoscale 2D leaf‐shaped MOF (NZIF−L) was synthesized via coordination self‐assembly between 2‐methylimidazole (Hmim) and Zn2+ with subsequent morphology and size control. The fabricated NZIF−L is cytocompatible and can be quickly endocytosed, which makes it an excellent cargo carrier. Subsequent to loading with either doxorubicin (DOX) or 4,4′‐(1,2‐diphenylvinyl)‐1,2‐di‐(phenylcarboxylic acid) (TCPE), the respectively obtained DOX@NZIF−L and TCPE@NZIF−L showed promise for killing and imaging cancer cells.
Study of MHD dynamo effect at the outlet from plasma accelerator in the presence of longitudinal magnetic field
Authors: Kozlov Andrei N.
Published: January 2020

Properties of compressible flows in the quasi‐stationary plasma accelerator have been studied in the presence of an additional longitudinal magnetic field and the arising rotation of plasma flow. Numerical study was carried out within the framework of two‐dimensional magnetic hydrodynamics (MHD) model of the axisymmetric plasma flows taking into account the finite conductivity of medium and radiation transport. Dynamics of compressible plasma flows is accompanied by the MHD dynamo effect or generation of magnetic field on a conical shock wave forming at the outlet from the accelerator.
Enhanced redesigned spatial modulation: Design and performance evaluation under correlated fading channels
Authors: Gudla Vishnu Vardhan , Kumaravelu Vinoth Babu
Published: January 2020

Spatial modulation techniques (SMTs) have emerged as promising multiple‐input and multiple‐output (MIMO) technology for fifth generation (5G) networks, which can achieve an appealing trade‐off between conflicting design objectives such as reliability, hardware cost, complexity, spectral efficiency, and energy efficiency. Most of the SMTs suffer from significant performance deterioration under correlated fading channels. In this paper, a novel spectral efficient SMT referred as enhanced redesigned spatial modulation (EReSM) is proposed, which is robust against adverse channel correlation effects. At any time instant, EReSM activates either one or two transmit antennas and employs a robust bits to antenna index mapping that ensures the selection of antenna subsets with maximum spatial separation to mitigate the effect of spatial correlation. EReSM also exploits phase rotation of transmitted symbols as an additional dimension to convey an extra information bit. The rotation angles used for bit mapping are optimized for various modulation schemes to maximize the minimum euclidean distance between the symbols. To analyze the performance, analytical upper bound expression for average bit error probability (ABEP) is derived for both uncorrelated and spatially correlated channel conditions. Monte Carlo simulation results substantiate the accuracy of the analytical results and also demonstrate that the proposed EReSM outperform conventional redesigned spatial modulation (ReSM) by at least 4 dB.
SOS: Self‐organized secure framework for VANET
Authors: Salem Fatty M. , Ali Ahmed S.
Published: January 2020

While authentication is a necessary requirement to provide security in vehicular ad hoc networks, user's personal information such as identity and location must be kept private. The reliance on road side units or centralized trusted authority nodes to provide security services is critical because both are vulnerable, thus cannot be accessed by all users, which mean security absence. In this paper, we introduce a self‐organized secure framework, deployed in vehicular ad hoc networks. The proposed framework solution is designed not only to provide an effective, integrated security and privacy‐preserving mechanism but also to retain the availability of all security services even if there are no road side units at all and/or the trusted authority node is compromised. A decentralized tier‐based security framework that depends on both trusted authority and some fully trusted nodes cooperated to distribute security services is presented. Our approach combines the useful features of both Shamir secret sharing with a trust‐based technique to ensure continuity of achieving all security services. Mathematical analysis of security issues that the proposed framework achieves as well as the availability of offering security services is provided. Proposed framework examination was done to show the performance in terms of storage, computation complexity, and communication overhead as well as its resilience against various types of attacks. Comparisons with different types of security schemes showed that the protocol developed gave better results in most comparison parameters while being unique ensuring continuity of security services delivery.
The influence of governance rearrangements on flood risk management in Kampala, Uganda
Authors: Chereni Simbarashe , Sliuzas Richard V. , Flacke Johannes , Maarseveen Martin V.
Published: January 2020

The importance of governance rearrangements (reassignment of positions, roles, and responsibility among actors in governance processes) and their implications on flood risk management has gained currency in evaluative environmental governance literature. However, much work has concentrated on building and applying frameworks to evaluate impacts of decentralisation, such that frameworks to evaluate impacts of recentralisation are still lacking. This paper uses the case of Bwaise III informal settlement in Kampala, Uganda, to assess the impacts of local government rearrangements on flood mitigation. We adapted a Water Governance Assessment Framework and conducted 22 in‐depth interviews with stakeholders, searched documentary sources, and carried out transect walks. We generated qualitative data on stakeholder experiences and perceptions regarding governance quality and flood mitigation prereform and postreform. The data were analysed using thematic content analysis to produce a scoreboard measuring changes in governance dimensions against progress in flood mitigation. In a follow‐up survey, 24 structured interviews were conducted to validate the data. Results show that the rearrangements led to time and cost savings, increased revenue, and sped up the implementation of flood management strategies and measures. The findings can be useful to policymakers at the interface of governance and flood management.
Hypertrophic cardiomyopathy: the future of treatment
Authors: Tuohy C. Vaughan , Kaul Sanjiv , Song Howard K. , Nazer Babak , Heitner Stephen B.
Published: January 2020

Hypertrophic cardiomyopathy (HCM) is a heterogeneous genetic disorder most often caused by sarcomeric mutations resulting in left ventricular hypertrophy, fibrosis, hypercontractility, and reduced compliance. It is the most common inherited monogenic cardiac condition, affecting 0.2% of the population. Whereas currently available therapies for HCM have been effective in reducing morbidity, there remain important unmet needs in the treatment of both the obstructive and non‐obstructive phenotypes. Novel pharmacotherapies directly target the molecular underpinnings of HCM, while innovative procedural techniques may soon offer minimally‐invasive alternatives to current septal reduction therapy. With the advent of embryonic gene editing, there now exists the potential to correct underlying genetic mutations that may result in disease. This article details the recent developments in the treatment of HCM including pharmacotherapy, septal reduction procedures, mitral valve manipulation, and gene‐based therapies.
Genetic risk and atrial fibrillation in patients with heart failure
Authors: Kloosterman Mariëlle , Santema Bernadet T. , Roselli Carolina , Nelson Christopher P. , Koekemoer Andrea , Romaine Simon. P.R. , Van Gelder Isabelle C. , Lam Carolyn S.P. , Artola Vicente A. , Lang Chim C. , Ng Leon L. , Metra Marco , Anker Stefan , Filippatos Gerasimos , Dickstein Kenneth , Ponikowski Piotr , van der Harst Pim , van der Meer Peter , van Veldhuisen Dirk J. , Benjamin Emelia J. , Voors Adriaan A. , Samani Nilesh J. , Rienstra Michiel
Published: January 2020

Aims

To study the association between an atrial fibrillation (AF) genetic risk score with prevalent AF and all‐cause mortality in patients with heart failure.

Methods and results

An AF genetic risk score was calculated in 3759 European ancestry individuals (1783 with sinus rhythm, 1976 with AF) from the BIOlogy Study to TAilored Treatment in Chronic Heart Failure (BIOSTAT‐CHF) by summing 97 single nucleotide polymorphism (SNP) alleles (ranging from 0–2) weighted by the natural logarithm of the relative SNP risk from the latest AF genome‐wide association study. Further, we assessed AF risk variance explained by additive SNP variation, and performance of clinical or genetic risk factors, and the combination in classifying AF prevalence. AF was classified as AF or atrial flutter (AFL) at baseline electrocardiogram and/or a history of AF or AFL. The genetic risk score was associated with AF after multivariable adjustment. Odds ratio for AF prevalence per 1‐unit increase genetic risk score was 2.12 (95% confidence interval 1.84–2.45, P = 2.15 × 10−24) in the total cohort, 2.08 (1.72–2.50, P = 1.30 × 10−14) in heart failure with reduced ejection fraction (HFrEF) and 2.02 (1.37–2.99, P = 4.37 × 10−4) in heart failure with preserved ejection fraction (HFpEF). AF‐associated loci explained 22.9% of overall AF SNP heritability. Addition of the genetic risk score to clinical risk factors increased the C‐index by 2.2% to 0.721.

Conclusions

The AF genetic risk score was associated with increased AF prevalence in HFrEF and HFpEF. Genetic variation accounted for 22.9% of overall AF SNP heritability. Addition of genetic risk to clinical risk improved model performance in classifying AF prevalence.
Activation and Functionalization of Dinitrogen in the Presence of Molecular Hydrogen Promoted by Transition Metal Complexes
Authors: Sivasankar Chinnappan , Madarasi Packirisamy Kuzhalmozhi , Tamizmani Masilamani
Published: January 2020

The quest for functionalization of dinitrogen has been a challenging task for decades, owing to its high redox potential. The transition metal dinitrogen complex made by Allen and Senoff provoked the researchers to functionalize dinitrogen and produce ammonia either stoichiometrically or catalytically using mild reaction conditions. Predominantly there are two methodologies available for the functionalization of dinitrogen. In the first methodology, proton and electron sources are used for the functionalization of dinitrogen, which is similar to biological nitrogen fixation. In the second methodology, molecular hydrogen is used for the functionalization of dinitrogen, which is similar to the Haber–Bosch process. Nonetheless, the Haber–Bosch process is the only successful industrial methodology for the production of ammonia. However, this methodology is highly energy consuming. Hence, there is a necessity for a practically viable homogeneous catalyst that could replace the heterogeneous Haber–Bosch process and thus conserve energy. However, there are very few reports on the utilization of molecular hydrogen for the functionalization of dinitrogen owing to the difficulty in handling dinitrogen and molecular hydrogen in a single, reactor because the relatively more acidic molecular hydrogen could replace the dinitrogen. Nonetheless, only the proton part of H2 has been used and yet it is hoped to utilize the hydride part of H2 in the near future. This review article describes the various endeavors made by the researchers to utilize molecular hydrogen for the functionalization of dinitrogen.