bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transcatheter mitral valve implantation in rigid mitral annuloplasty rings: Potential differences between complete and incomplete rings
Authors: Hachinohe Daisuke , Latib Azeem , Montorfano Matteo , Colombo Antonio 
Published: May 2018

AbstractTranscatheter mitral valve implantation (TMVI) has been performed in high‐risk and inoperable patients for degenerated mitral bioprostheses (TMVIinV) and failed annuloplasty rings (TMVIinR). TMVIinR is more challenging compared to TMVIinV because of the differences in dimensions, shapes, and contours between rings and valves. In this report, we present two clinical cases of TMVIinR that were treated by trans‐septal implantation of a balloon‐expandable prosthesis. In TMVI cases with an incomplete ring, the ring will be stretched out toward its anterior and commissural side, and the open side of the ring will increase in width. The ring may not transform in line with the shape of the transcatheter heart valve (THV) and an interspace can develop between the THV and the ring at the commissural side, resulting in significant paravalvular regurgitation. Our experience suggests that the circumferential completeness of the rings may be an important factor to consider when planning a TMVIinR.
Water Oxidation Electrocatalysis with a Cobalt‐Borate‐Based Hybrid System under Neutral Conditions
Authors: Turhan Emine A. , Nune Satya Vijaya Kumar , Ülker Emine , Şahin Ufuk , Dede Yavuz , Karadas Ferdi 
Published: May 2018

AbstractThe development of new water oxidation electrocatalysts that are both stable and efficient, particularly in neutral conditions, holds great promise for overall water splitting. In this study, the electrocatalytic water oxidation performance of a new cobalt‐based catalyst, Co3(BO3)2, with a Kotoite‐type crystal structure is investigated under neutral conditions. The catalyst is also hybridized with CNTs to enhance its electrocatalytic properties. A remarkable increase in catalytic current along with a significant shift in the onset overpotential is observed in Co3(BO3)2@CNT. Additionally, CNT addition also greatly influences the surface concentration of the catalyst: 12.7 nmol cm−2 for Co3(BO3)2@CNT compared with 3.9 nmol cm−2 for Co3(BO3)2. Co3(BO3)2@CNT demands overpotentials of 303 and 487 mV to attain current densities of 1 and 10 mA cm−2, respectively, at pH 7. Electrochemical and characterization studies performed over varying pH conditions reveal that the catalyst retains its stability over a pH range of 3–14. Multi‐reference quantum chemical calculations are performed to study the nature of the active cobalt sites and the effect of boron atoms on the activity of the cobalt ions.
Divergent, Enantioselective Synthesis of Pyrroles, 3H‐Pyrroles and Bicyclic Imidazolines by Ag‐ or P‐Catalyzed [3+2] Cycloaddition of Allenoates with Activated Isocyanides
Authors: Kok Germaine Pui Yann , Shao Pan‐Lin , Liao Jia‐Yu , Ismail Siti Nur Fairuz Bte Sheikh , Yao Weijun , Lu Yixin , Zhao Yu 
Published: May 2018

AbstractThe divergent, stereoselective formal [3+2] cycloadditions of allenoates with activated isocyanides catalyzed by silver or phosphine‐based catalysts were investigated. Silver catalysis is capable of delivering a range of 3H‐pyrroles in high stereoselectivities. These enantioenriched heterocycles can either undergo sequential cyclisation with isocyanoacetates to deliver unprecedented bicyclic imidazolines with excellent yields and stereoselectivity or undergo unusual aromatization pathways leading to polysubstituted pyrroles. On the other hand, a simple mix‐and‐go procedure using an amino acid‐derived phosphine as the catalyst produces pyrroles bearing a benzylic stereocenter with good enantioselectivity.
Site‐Selective γ‐C(sp3)−H and γ‐C(sp2)−H Arylation of Free Amino Esters Promoted by a Catalytic Transient Directing Group
Authors: Lin Hua , Wang Chao , Bannister Thomas D. , Kamenecka Theodore M. 
Published: May 2018

AbstractThe first selective PdII‐catalysed γ‐C(sp3)−H and γ‐C(sp2)−H arylation of free amino esters using a commercially available catalytic transient directing group. A variety of free amino esters, including α‐amino esters and β‐amino esters, amino monoesters and amino bis‐esters, are shown to react with a diverse range of simple aryl and heteroaryl iodide reagents.
Enantioselective Synthesis of All‐Carbon Quaternary Centers Structurally Related to Amaryllidaceae Alkaloids
Authors: Mikušek Jiří , Jansa Petr , Jagtap Pratap R. , Vašíček Tomáš , Císařová Ivana , Matoušová Eliška 
Published: May 2018

AbstractEnantioselective synthesis of all‐carbon quaternary centers remains a considerable challenge for synthetic organic chemists. Here, we report a two‐step protocol to synthesize such centers including tandem cyclization/Suzuki cross‐coupling followed by halocarbocyclization. During this process, two rings, three new C−C bonds and a stereochemically defined all‐carbon quaternary center are formed. The absolute configuration of this center is controlled by the stereochemistry of the adjacent stereocenter, which derives from an appropriate enantioenriched starting material. Using this method, we synthesized polycyclic compounds structurally similar to Amaryllidaceae alkaloids in high enantiomeric excesses. Because these products resemble naturally occurring compounds, our protocol can be used to synthesize various potentially bioactive compounds.
Reoptimization of the Organocatalyzed Double Aldol Domino Process to a Key Enal Intermediate and Its Application to the Total Synthesis of Δ12‐Prostaglandin J3
Authors: Pelšs Andrejs , Gandhamsetty Narasimhulu , Smith James R. , Mailhol Damien , Silvi Mattia , Watson Andrew J. A. , Perez‐Powell Isabel , Prévost Sébastien , Schützenmeister Nina , Moore Peter R. , Aggarwal Varinder K. 
Published: May 2018

AbstractRe‐investigation of the l‐proline catalyzed double aldol cascade dimerization of succinaldehyde for the synthesis of a key bicyclic enal intermediate, pertinent in the field of stereoselective prostaglandin synthesis, is reported. The yield of this process has been more than doubled, from 14 % to a 29 % isolated yield on a multi‐gram scale (32 % NMR yield), through conducting a detailed study of the reaction solvent, temperature, and concentration, as well as a catalyst screen. The synthetic utility of this enal intermediate has been further demonstrated through the total synthesis of Δ12‐prostaglandin J3, a compound with known anti‐leukemic properties.
Influence of sex and pregnancy on survival in patients admitted with heart failure: Data from a prospective multicenter registry
Authors: Martínez‐Sellés Manuel , Díez‐Villanueva Pablo , Álvarez Garcia Jesús , Ferrero‐Gregori Andreu , Vives‐Borrás Miquel , Worner Fernando , Bardají Alfredo , Delgado Juan F. , Vázquez Rafael , González‐Juanatey José R. , Fernández‐Aviles Francisco , Cinca Juan 
Published: May 2018

BackgroundFemale sex is an independent predictor of better survival in patients with heart failure (HF), but the mechanism of this association is unknown. On the other hand, pregnancies have a strong influence on the cardiovascular system.HypothesisSex and previous gestations might have a prognostic impact on 1‐year mortality in patients admitted with HF.MethodsWe conducted an observational, prospective, consecutive, multicenter registry of 1831 patients (756 females [41.2%]) admitted with HF.ResultsFemales had a more advanced age (75.2 ±11.4 vs 70.4 ±12.2 years), less ischemic heart disease (167 [25.3%] vs 446 [47.3%]), and higher left ventricular ejection fraction (52.0% ±16.6% vs 41.1% ±17.0%) than did men (all P values <0.001). During 1‐year follow‐up, 373 (20.4%) patients died (151 females and 222 males). Female sex was an independent predictor for survival (hazard ratio: 0.79, 95% confidence interval: 0.64–0.98, P = 0.03). In 504 women (65.9%), the exact number of previous pregnancies could be determined; 62 women (12.3%) had no previous pregnancies, 288 (57.1%) women had 1 or 2 pregnancies, and 154 women (30.6%) had ≥3 pregnancies. We found an association between the number of previous gestations and better survival (hazard ratio: 0.878, 95% confidence interval: 0.773–0.997, P = 0.045).ConclusionsIn patients admitted with HF, female sex and the number of previous pregnancies are independently associated with better 1‐year survival.
Dual‐Responsive Carbon Dot for pH/Redox‐Triggered Fluorescence Imaging with Controllable Photothermal Ablation Therapy of Cancer
Authors: Choi Cheong A. , Lee Jung Eun , Mazrad Zihnil Adha Islamy , Kim Young Kwang , In Insik , Jeong Ji Hoon , Park Sung Young 
Published: May 2018

AbstractHerein we describe fluorescence resonance energy transfer (FRET) for a pH/redox‐activatable fluorescent carbon dot (FNP) to realize “off–on” switched imaging‐guided controllable photothermal therapy (PTT). The FNP is a carbonized self‐crosslinked polymer that allows IR825 loading (FNP[IR825]) via hydrophobic interactions for cancer therapy. Fluorescence bioimaging was achieved by the internalization of FNP(IR825) into tumor cells, wherein glutathione (GSH) disulfide bonds are reduced, and benzoic imine groups are cleaved under acidic conditions. The release of IR825 from the FNP core in this system may be used to efficiently control PTT‐mediated cancer therapy via its photothermal conversion after near‐infrared (NIR) irradiation. In vitro and in vivo cellular uptake studies revealed efficient uptake of FNP(IR825) by tumor cells to treat the disease site. In this way we demonstrated in mice that our smart nanocarrier can effectively kill tumor cells under exposure to a NIR laser, and that the particles are biocompatible with various organs. This platform responds sensitively to the exogenous environment inside the cancer cells and may selectively induce the release of PTT‐mediated cytotoxicity. Furthermore, this platform may be useful for monitoring the elimination of cancer cells through the fluorescence on/off switch, which can be used for various applications in the field of cancer cell therapy and diagnosis.
Collaborating visual tracker based on particle filter and correlation filter
Authors: Li Weiguang , Wei Wang , Qiang Han , Shi Mingquan 
Published: May 2018

SummaryCorrelation filter (CF)–based tracking algorithms is most popular in recent years due to its high accuracy and impressive speed. However, it has some intrinsically drawbacks such as margin suppression, sensitive for disturbance, and partial occlusions. Contrasted with CF drawbacks, the advantages of particle filter (PF) tracking algorithm include robustness, motion prediction, and wide detection range. Therefore, it can amend some CF tracker drawbacks. On the other hand, the HOG feature is widely used in CF tracker because it can detect the target precision position. However, this kind of feature is rotation‐variation, which is invalid for rotation transformation target. On the contrary, the tracker precision merely based on colour feature is rough, but colour feature is rotation invariation and is effective for rotating target; therefore, these two features are complementary. In this paper, we integrate both trackers (CF and PF) to learn the HOG and colour feature, respectively, experiments demonstrate this tracking algorithm is more robust, and the tracking precision is more accurate. This algorithm is integrated with some classic CF trackers (KCF, SAMF, and MOSSE) framework and benchmark them against their baseline. On the OTB2015 benchmark datasets, experiment result demonstrates OPE performance grades have improved from about 1% to 12%; SRE Performance grades have improved from about 1.3% to 5.8%.
Formation of Supramolecular Clusters at the Interface of Zeolite X Following the Adsorption of Rare‐Earth Cations and Their Impact on the Macroscopic Properties of the Zeolite
Authors: Guzzinati Roberta , Sarti Elena , Catani Martina , Costa Valentina , Pagnoni Antonella , Martucci Annalisa , Rodeghero Elisa , Capitani Donatella , Pietrantonio Massimiliana , Cavazzini Alberto , Pasti Luisa 
Published: May 2018

AbstractThe adsorption behavior of neodymium (Nd3+) and yttrium (Y3+) cations on synthetic FAU zeolite X in its sodium form (NaX) has been investigated by means of macroscopic (adsorption isotherm determination and thermal analysis) and microscopic measurements (including solid‐state NMR spectroscopy and X‐ray powder diffraction). The multidisciplinary study reveals some unexpected features. Firstly, adsorption constants of cations are not correlated to their ionic radii or hydration enthalpy. The adsorption constant of Y3+ on NaX was indeed about twice that of Nd3+, which is the opposite of what could be expected based on the size of the cations. In addition, adsorption was accompanied by partial dealumination of the zeolite framework. The extent of dealumination changed depending on the exchanged cations, with the extent being more significant on the Nd‐exchanged zeolite than on the Y‐exchanged one. The most interesting finding of this study, however, is the presence of supramolecular clusters composed of water, Nd3+, residual sodium ions, and extra‐framework aluminum at the interface of Nd‐exchanged zeolite. The hypothesis that these host‐guest complexes are responsible of the significantly different behavior exhibited by NaX towards the adsorption/desorption of Nd3+ and Y3+ has been formulated.
Newly Revised Quantitative PCR‐Based Assay for Mitochondrial and Nuclear DNA Damage
Authors: Sanders Laurie H. , Rouanet Jeremy P. , Howlett Evan H. , Leuthner Tess C. , Rooney John P. , Greenamyre J. Timothy , Meyer Joel N. 
Published: May 2018

AbstractGiven the crucial role of DNA damage in human health and disease, it is important to be able to accurately measure both mitochondrial and nuclear DNA damage. This article describes a method based on a long‐amplicon quantitative PCR–based assay that does not require a separate mitochondrial isolation step, which can often be labor‐intensive and generate artifacts. The detailed basic protocol presented here is newly revised, with particular attention to application in Homo sapiens, Rattus norvegicus, and Caenorhabditis elegans resulting from changes in availability of PCR reagents. Optimized extraction support protocols are also described for high‐quality DNA from multiple rat tissues for which these procedures had not previously been described. © 2018 by John Wiley & Sons, Inc.
Effective Separation of N‐benzyl‐2‐methyl‐4‐nitroaniline (BNA) Polymorphs through Antisolvent Crystallization Method
Authors: Kalaivanan Raju , Srinivasan Karuppannan 
Published: May 2018

AbstractThe Influence of antisolvent water on the polymorphic nucleation of N‐benzyl‐2‐methyl‐4‐nitroaniline (BNA) during its crystallization from methanol solution is revealed. The solubility of BNA in methanol‐water solvent mixtures is determined by gravimetric method and the variation in the level of supersaturation generated with respect to antisolvent concentration is assessed at different volume combinations of saturated methanol BNA solution and water. The supersaturation dependent polymorphic nucleation of orthorhombic and monoclinic forms and their growth morphologies such as platy‐like orthorhombic and needle‐like monoclinic are examined through in‐situ optical microscopy. Single crystals of the grown polymorphs are successfully separated and their structural, thermal, spectroscopic and optical transmittance properties are confirmed through PXRD, DSC, FTIR and UV‐Vis‐near IR analyses respectively.
Prevalence of nephropathy in type 1 diabetes in the Arab world: A systematic review and meta‐analysis
Authors: Abdel‐Motal Ussama M. , G Akila , Abdelalim Essam M. , Ponnuraja Chinnaiyan , Iken Khadija , Jahromi Mohamed , Doss George Priya , El Bekay Rajaa , Zayed Hatem 
Published: May 2018

SummaryThe aim of this study was to conduct a systematic review and meta‐analysis and determine the prevalence of diabetic nephropathy (DN) among Arab patients with T1D. A systematic literature search was conducted using 4 different literature databases (PubMed, ScienceDirect, Web of Science, and Embase) to capture all relevant data about Arab patients with T1D that had DN. Meta‐analysis and systematic review were performed using the random effect model, and the heterogeneity of the studies was assessed using the Q‐test, I2, and Tau‐squared statistics. Publication bias was assessed using the funnel‐plot test. Our search strategy captured 372 studies in only 10 out of the 22 Arab countries in a period of 48 years (1969‐2017); of which, 41 met our inclusion criteria for full article analysis, of those, 15 were eligible for meta‐analysis. We estimated the prevalence of DN among Arab people with T1D to be 18.2% (95% confidence interval 13.1%‐24.8%). In conclusion, DN prevalence is underexplored among Arab patients with T1D and represents a significant risk for the well‐being of Arab patients with T1D. Therefore, there is an urgent need for comprehensive epidemiological studies for DN among Arab patients with T1D.
Comparative studies of immobilized chiral stationary phases based on polysaccharide derivatives for enantiomeric separation of 15 azole compounds
Authors: Zhu Bolin , Deng Miaoduo , Yao Yaqi , Yu Jia , Li Qing 
Published: May 2018

AbstractImmobilized polysaccharide‐based columns showed excellent enantioselectivity in normal phase separation mode. In this work, enantioseparation abilities of four immobilized polysaccharide‐derived chiral stationary phases (Chiralpak IA, Chiralpak IB, Chiralpak IC, and Chiralpak ID) toward 15 azole compounds were evaluated. Separation was carried out using n‐hexane as mobile phase with ethanol, 1‐propanol, 1‐butanol, and 2‐propanol as modifiers. And twelve compounds have achieved baseline separation with the resolutions ranging between 2.05 and 21.73. The enantioseparation on the four polysaccharide‐based chiral columns using different alcohol modifiers was compared. In general, the best separation performance was identified as Chiralpak IC, which was able to resolve 11 compounds to baseline and two partially under the screening conditions. Separation on Chiralpak IB was not satisfactory, because only four compounds were baseline separated.
Comparative evaluation of sludge surface charge as an indicator of process fluctuations in a biogas reactor
Authors: Winde Lars , Berghoff Anne , Schories Gerhard , Mahro Bernd 
Published: May 2018

AbstractThe current political situation imposes high demands on the economic feasibility of biogas plants. High prizes for biogas substrates and a trend to reduced feed‐in tariffs generated an increasing need to optimize substrate exploitation and operation conditions. This includes a comprehensive and reliable biogas process monitoring. For that purpose a number of different process monitoring methods like CH4 production rate, FOS/TAC (ratio of organic acid/total inorganic carbon alkalinity), pH or (auto)fluorescence are successfully applied. This paper will evaluate whether the surface charge — a parameter, which has not been in use so far — might also be suitable for biogas process monitoring. Since it is known that the surface charge is correlated with the adherence and floc formation capability of microbial cells, a change in surface charge might also reflect a change in the biogas process efficiency, or vice versa. To test this hypothesis, samples for the investigations were taken from a continuously stirred laboratory‐scale tank biogas reactor with continuously increased substrate load. The impact of the load change was measured with both, surface charge and a number of more established monitoring parameters as given above. It was found that the “surface charge” reflected well short‐term process changes (within hours) caused by an increasing substrate load in the reactor, though the highest short‐term monitoring sensitivity was obtained with the “FOS/TAC” monitoring. Different from other monitoring parameters like CH4, pH, or FOS/TAC the value of the parameter “surface charge” decreased with every feeding, eventually indicating a continuous deterioration of the biogas process conditions. Surface charge might therefore be of particular use as a complementary tool especially for the long‐term monitoring of biogas process conditions.
Thermostable enzymes and polysaccharides produced by thermophilic bacteria isolated from Bulgarian hot springs
Authors: Kambourova Margarita 
Published: May 2018

AbstractThermostable enzymes (thermozymes) have been recognized as extremophilic compounds with a greatest biotechnological importance in different industrial areas. Quite recently exopolysaccharides (EPSs) synthesized by thermophiles became an object of increased research interest due to their unique properties appropriate for some specific industrial needs. Thermophilic producers of biotechnologically valuable enzymes and novel EPS were isolated by our group from Bulgarian thermal springs with a diverse geotectonic origin and different water properties. Laboratory reactor processes for their production were developed in batch and continuous cultures. Some of the synthesized thermostable enzymes were among the first described in their groups, for example, the single known thermostable gellan lyase that demonstrated specific activity higher than that of the mesophilic enzymes. Isolated by us thermostable xylanase was able to degrade more than 60% of beechwood xylan in a coprocess with an archaeal β‐xylosidase. Lipase purified by us was active between 55 and 90°C with an optimum at 75–80°C in a large pH range. It was able to degrade a broad range of substrates. Isolates from Bulgarian hot springs synthesized EPS with novel composition and high thermostability. Thus, Bulgarian hot springs harbor a wide set of thermophilic producers of novel enzymes and EPS with potential for a large number of biotechnological applications.
Adapting population models for application in pesticide risk assessment: A case study with Mead's milkweed
Authors: Schmolke Amelie , Roy Colleen , Brain Richard , Forbes Valery 
Published: May 2018

Abstract

Population models can facilitate assessment of potential impacts of pesticides on populations or species rather than individuals and have been identified as important tools for pesticide risk assessment of nontarget species including those listed under the Endangered Species Act. Few examples of population models developed for this specific purpose are available; however, population models are commonly used in conservation science as a tool to project the viability of populations and the long-term outcomes of management actions. We present a population model for Mead's milkweed (Asclepias meadii), a species listed as threatened under the Endangered Species Act throughout its range across the Midwestern United States. We adapted a published population model based on demographic field data for application in pesticide risk assessment. Exposure and effects were modeled as reductions of sets of vital rates in the transition matrices, simulating both lethal and sublethal effects of herbicides. Two herbicides, atrazine and mesotrione, were used as case study examples to evaluate a range of assumptions about potential exposure–effects relationships. In addition, we assessed buffers (i.e., setback distances of herbicide spray applications from the simulated habitat) as hypothetical mitigation scenarios and evaluated their influence on population-level effects in the model. The model results suggest that buffers can be effective at reducing risk from herbicide drift to plant populations. These case studies demonstrate that existing population models can be adopted and integrated with exposure and effects information for use in pesticide risk assessment. Environ Toxicol Chem 2018;37:2235–2245. © 2018 SETAC
Abstract
A model based on demographic field data of a threatened milkweed is applied to assess potential long-term population-level effects of exposure to herbicide spray drift. Uncertainties in effects are addressed with multiple scenarios.