bluuebunny/crossref_metadata_2025_split huggingface dataset:
Catalytic Asymmetric Epoxidation of Electron‐Deficient Enynes Promoted by Chiral N,N′‐Dioxide‐Scandium(III) Complex
Authors: Zhang Hang , Yao Qian , Lin Lili , Xu Chaoran , Liu Xiaohua , Feng Xiaoming 
Published: July 2017

AbstractAn asymmetric epoxidation of electron‐deficient enynes with environmentally benign aqueous hydrogen peroxide as oxidant has been accomplished by developing a chiral N,N′‐dioxide‐Scandium(III) complex catalytic system. In the presence of 0.5–2 mol% catalyst, a variety of trisubstituted alkynyl oxiranes were obtained in high yields (up to 97%) with excellent ee values (up to 99%). Furthermore, control experiments provide a fundamental insight into the reaction mechanism.magnified image
Teaching Quality Improvement in Emergency Medicine Training Programs: A Review of Best Practices
Authors: Mondoux Shawn , Chan Teresa M. , Ankel Felix , Sklar David P. 
Published: July 2017

AbstractInternational graduate medical accreditation bodies are placing increasing emphasis on resident education and competency in the principles of quality improvement and patient safety (QIPS). Current QIPS educational curricula are heterogeneous and variably attain stated objectives. We have conducted a review of QIPS curricular best practices and barriers to implementation of successful QIPS curricula and provide clear solutions aimed at overcoming these barriers. Emergency medicine programs provide fertile ground for QIPS initiatives and can become world leaders in QIPS curricular development and education.
A craniometric analysis of early modern Romania and Hungary: The roles of migration and conversion in shaping European Ottoman population history
Authors: Allen Kathryn Grow , von Cramon‐Taubadel Noreen 
Published: July 2017

AbstractObjectivesDebate persists regarding the biological makeup of European Ottoman communities settled during the expansion of the Ottoman Empire during the 16th and 17th centuries, and the roles of conversion and migration in shaping demography and population history. The aim of this study was to perform an assessment of the biological affinities of three European Ottoman series based on craniometric data.Materials and MethodsCraniometric data collected from three Ottoman series from Hungary and Romania were compared to European and Anatolian comparative series, selected to represent biological affinity representative of historically recorded migration and conversion influences. Sex‐separated samples were analyzed using D2‐matrices, along with principal coordinates and PERMANOVA analyses to investigate biological affinities. Discriminant function analysis was employed to assign Ottoman individuals to two potential classes: European or Anatolian.ResultsAffinity analyses show larger than expected biological differences between males and females within each of the Ottoman communities. Discriminant function analyses show that the majority of Ottoman individuals could be classified as either European or Anatolian with a high probability. Moreover, location within Europe proved influential, as the Ottomans from a location of more geopolitical importance (Budapest) diverged from more hinterland communities in terms of biological affinity patterns.DiscussionThe results suggest that male and female Ottomans may possess distinct population histories, with males and females divergent from each other in terms of their biological affinities. The Ottoman communities appear diverse in terms of constituting a mix of peoples from different biological backgrounds. The greater distances between sexes from the same community, and the differences between communities, may be evidence that the processes of migration and conversion impacted individual people and groups diversely.
Combined electroencephalography–functional magnetic resonance imaging and electrical source imaging improves localization of pediatric focal epilepsy
Authors: Centeno Maria , Tierney Tim M. , Perani Suejen , Shamshiri Elhum A. , St Pier Kelly , Wilkinson Charlotte , Konn Daniel , Vulliemoz Serge , Grouiller Frédéric , Lemieux Louis , Pressler Ronit M. , Clark Christopher A. , Cross J. Helen , Carmichael David W. 
Published: July 2017

ObjectiveSurgical treatment in epilepsy is effective if the epileptogenic zone (EZ) can be correctly localized and characterized. Here we use simultaneous electroencephalography–functional magnetic resonance imaging (EEG‐fMRI) data to derive EEG‐fMRI and electrical source imaging (ESI) maps. Their yield and their individual and combined ability to (1) localize the EZ and (2) predict seizure outcome were then evaluated.MethodsFifty‐three children with drug‐resistant epilepsy underwent EEG‐fMRI. Interictal discharges were mapped using both EEG‐fMRI hemodynamic responses and ESI. A single localization was derived from each individual test (EEG‐fMRI global maxima [GM]/ESI maximum) and from the combination of both maps (EEG‐fMRI/ESI spatial intersection). To determine the localization accuracy and its predictive performance, the individual and combined test localizations were compared to the presumed EZ and to the postsurgical outcome.ResultsFifty‐two of 53 patients had significant maps: 47 of 53 for EEG‐fMRI, 44 of 53 for ESI, and 34 of 53 for both. The EZ was well characterized in 29 patients; 26 had an EEG‐fMRI GM localization that was correct in 11, 22 patients had ESI localization that was correct in 17, and 12 patients had combined EEG‐fMRI and ESI that was correct in 11. Seizure outcome following resection was correctly predicted by EEG‐fMRI GM in 8 of 20 patients, and by the ESI maximum in 13 of 16. The combined EEG‐fMRI/ESI region entirely predicted outcome in 9 of 9 patients, including 3 with no lesion visible on MRI.InterpretationEEG‐fMRI combined with ESI provides a simple unbiased localization that may predict surgery better than each individual test, including in MRI‐negative patients. Ann Neurol 2017;82:278–287.
Seizure activity per se does not induce tissue damage markers in human neocortical focal epilepsy
Authors: Rossini Laura , Garbelli Rita , Gnatkovsky Vadym , Didato Giuseppe , Villani Flavio , Spreafico Roberto , Deleo Francesco , Lo Russo Giorgio , Tringali Giovanni , Gozzo Francesca , Tassi Laura , de Curtis Marco 
Published: July 2017

ObjectiveThe contribution of recurring seizures to the progression of epileptogenesis is debated. Seizure‐induced brain damage is not conclusively demonstrated either in humans or in animal models of epilepsy. We evaluated the expression of brain injury biomarkers on postsurgical brain tissue obtained from 20 patients with frequent seizures and a long history of drug‐resistant focal epilepsy.MethodsThe expression patterns of specific glial, neuronal, and inflammatory molecules were evaluated by immunohistochemistry in the core of type II focal cortical dysplasias (FCD‐II), at the FCD boundary (perilesion), and in the adjacent normal‐appearing area included in the epileptogenic region. We also analyzed surgical specimens from cryptogenic patients not presenting structural alterations at imaging.ResultsAstroglial and microglial activation, reduced neuronal density, perivascular CD3‐positive T‐lymphocyte clustering, and fibrinogen extravasation were demonstrated in the core of FCD‐II lesions. No pathological immunoreactivity was observed outside the FCD‐II or in cryptogenetic specimens, where the occurrence of interictal and ictal epileptiform activity was confirmed by either stereo‐electroencephalography or intraoperative electrocorticography.InterpretationRecurrent seizures do not induce the expression of brain damage markers in nonlesional epileptogenic cortex studied in postsurgical tissue from cryptogenic and FCD patients. This evidence argues against the hypothesis that epileptiform activity per se contributes to focal brain injury, at least in the neocortical epilepsies considered here. Ann Neurol 2017;82:331–341
Porphyrin Antennas on Carbon Nanodots: Excited State Energy and Electron Transduction
Authors: Arcudi Francesca , Strauss Volker , Đorđević Luka , Cadranel Alejandro , Guldi Dirk M. , Prato Maurizio 
Published: July 2017

AbstractWe report the synthesis and electron donor–acceptor features of a novel nanohybrid, in which the light‐harvesting and electron‐donating properties of a meso‐tetraarylporphyrin (TArP) are combined with the electron‐accepting features of nitrogen‐doped carbon nanodots (NCNDs). In particular, in an ultrafast process (>1012 s−1), visible‐light excitation transforms the strongly quenched porphyrin singlet excited states into short‐lived (225 ps) charge‐separated states. On the other hand, ultraviolet light excitation triggers a non‐resolvable transduction of singlet excited state energy from the NCNDs to the porphyrins, followed by the same charge separation observed upon visible light excitation.
A Highly Efficient Chemiluminescence Probe for the Detection of Singlet Oxygen in Living Cells
Authors: Hananya Nir , Green Ori , Blau Rachel , Satchi‐Fainaro Ronit , Shabat Doron 
Published: July 2017

AbstractSinglet oxygen is among the reactive oxygen species (ROS) with the shortest life‐times in aqueous media because of its extremely high reactivity. Therefore, designing sensors for detection of 1O2 is perhaps one of the most challenging tasks in the field of molecular probes. Herein, we report a highly selective and sensitive chemiluminescence probe (SOCL‐CPP) for the detection of 1O2 in living cells. The probe reacts with 1O2 to form a dioxetane that spontaneously decomposes under physiological conditions through a chemiexcitation pathway to emit green light with extraordinary intensity. SOCL‐CPP demonstrated promising ability to detect and image intracellular 1O2 produced by a photosensitizer in HeLa cells during photodynamic therapy (PDT) mode of action. Our findings make SOCL‐CPP the most effective known chemiluminescence probe for the detection of 1O2. We anticipate that our chemiluminescence probe for 1O2 imaging would be useful in PDT‐related applications and for monitoring 1O2 endogenously generated by cells in response to different stimuli.
Pot Economy in the Total Synthesis of Estradiol Methyl Ether by Using an Organocatalyst
Authors: Hayashi Yujiro , Koshino Seitaro , Ojima Kanna , Kwon Eunsang 
Published: July 2017

AbstractEnantioselective total synthesis of estradiol methyl ether has been accomplished in a pot‐economical manner using five reaction vessels and four purifications. The key reaction is a diphenylprolinol silyl ether mediated domino Michael/aldol reaction to afford bicyclo[4.3.0]nonane derivatives, containing the A, C, and D rings of steroids, as a single isomer with excellent enantioselectivity. Six reactions such as oxidation, hydrogenation, formation of acid chloride, Friedel–Crafts reaction, deprotection, and reduction can be carried out in the last one‐pot sequence.
Molecular structure, molecular docking, thermal, spectroscopic and biological activity studies of bis‐Schiff base ligand and its metal complexes
Authors: Zayed Ehab M. , Hindy Ahmed M.M. , Mohamed Gehad G. 
Published: July 2017

Coordination compounds of Fe(III), Zn(II), Ni(II), Co(II), Cu(II), Cd(II) and Mn(II) ions were synthesized from the ligand [4,4′‐((((ethane‐1,2‐diylbis(oxy))bis(2,1‐phenylene))bis(methanylylidene))bis(azanylylidene))diphenol]ethane (H2L) derived from the condensation of bisaldehyde and 4‐aminophenol. Microanalysis, magnetic susceptibility, infrared, 1H NMR and mass spectroscopies, molar conductance, X ray powder diffraction and thermal analysis were used to confirm the structure of the synthesized chelates. According to the data obtained, the composition of the 1:1 metal ion–bis‐Schiff base ligand was found to be [M(H2L)(H2O)2]Cln (M = Zn(II), Ni(II), Co(II), Cu(II), Cd(II) and Mn(II), n = 2; Fe(III), n = 3). Magnetic susceptibility measurements and reflectance spectra suggested an octahedral geometry for the complexes. Central metals ions and bis‐Schiff base coordinated together via O2 and N2 donor sites which as evident from infrared spectra. The Gaussian09 program was applied to optimize the structural formula for the investigated Schiff base ligand. The energy gaps and other important theoretical parameters were calculated applying the DFT/B3LYP method. Molecular docking using AutoDock tools was utilized to explain the experimental behaviour of the Schiff base ligand towards proteins of Bacillus subtilis (5 h67), Escherichia coli (3 t88), Proteus vulgaris (5i39) and Staphylococcus aureus (3ty7) microorganisms through theoretical calculations. The docked protein receptors were investigated and the energies of hydrogen bonding were calculated. These complexes were then subjected to in vitro antibacterial studies against several organisms, both Gram negative (P. vulgaris and E. coli) and Gram positive (S. pyogones and B. subtilis). The ligand and metal complexes exhibited good microbial activity against the Gram‐positive and Gram‐negative bacteria.
In situ carbon deposition in polyetherimide/SAPO‐34 mixed matrix membrane for efficient CO2/CH4 separation
Authors: Sen Mitali , Das Nandini 
Published: July 2017

ABSTRACTA simple method of pore modification complied with defect removal polymer zeolite mixed matrix membrane was developed by in situ carbon (C) deposition. The C deposition was achieved by the controlled decomposition of polymer matrix by heat treatment. In this study, polyetherimide/silicoaluminophosphate‐34 mixed matrix membrane (MMM) was fabricated on clay‐alumina support tube, followed by carbonization of the polymer matrix for gas separation application. MMM without heat treatment were also synthesized for comparison by conventional method. The membranes were characterized by X‐ray diffraction, field emission scanning electron microscopy, and X‐ray photoelectron spectroscopy. Due to carbonization, in situ C nanoparticles were deposited in to the interfacial pores, and filler particles were oriented in preferable direction. The presence of CO, CN, and graphitic carbon in the matrix, may be an indication of partial carbonization and restoration of adherence of polymer with substrate. The separation factor for CO2/CH4 achieved 39.15 with a permeance value of 23.01 × 10−8mol/(m2 s Pa) for CO2 at 30 °C and 200 kPa feed pressure. For the first time, this work shows an improvement toward permeability of MMM by simple carbonization of polymer matrix with commendable values as compare to the reported literature. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45508.
Nonhalogen flame retarded poly(butylene terephthalate) composite using aluminum phosphinate and phosphorus‐containing deoxybenzoin polymer
Authors: Hu Xilong , Wang Yan , Yu Junrong , Zhu Jing , Hu Zuming 
Published: July 2017

ABSTRACTSynergistic charring effect was observed between aluminum diethlyphosphinate (AlPi) and 4,4‐bishydroxydeoxybenzoin‐polyphosphonate (BHDB‐PPN) in the poly(butylene terephthalate) composite. By combining them together, robust UL 94 V0 rating was achieved at 0.8 mm thickness for poly(butylene terephthalate)/AlPi/BHDB‐PPN composite which exhibited better mechanical properties than the samples without BHDB‐PPN. The thermal degradation behavior of BHDB‐PPN was investigated by analyzing its evolution and residues under different temperatures. It was found that the radical termination reaction of formed benzyl group may play a critical role in the high charring capacity of BHDB‐PPN. Part of the volatile diethlyphosphinate fragments reacted with the degradation intermediates from BHDB‐PPN to form big chain structure for further carbonization was a possible reason for the synergistic charring effect between AlPi and BHDB‐PPN. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45537.
Experimental investigation of the effects of different chemical absorbents on wetting and morphology of poly(vinylidene fluoride) membrane
Authors: Rezaiyan Zeynab , Keshavarz Peyman , Khorram Mohammad 
Published: July 2017

ABSTRACTMembrane wetting is of one the most important factor that affects the CO2 absorption efficiency in membrane contactors due to the increase of mass transfer resistance. In this study, the effects of different absorbents on the wettability of poly(vinylidene fluoride) membranes were investigated. Four absorbents including monoethanolamine, potassium carbonate–piperazine (PZ), potassium carbonate–monoethanolamine, and methyldiethanolamine–PZ were applied to investigate the effects of different absorbents on membrane wetting. Membrane properties before and after contact with absorbents were investigated using methods of thermogravimetric analysis, Fourier transform infrared spectroscopy, electron scanning microscope, and contact angle measurements. The results revealed that methyldiethanolamine and mixed absorbents containing methyldiethanolamine caused the most morphological changes in membrane. The results showed that reduction percentages of contact angle for water, K2CO3/PZ, K2CO3/MEA, MEA, and MDEA/PZ solutions were 14.52, 16.9, 21.19, 23.7, and 28.33, respectively, after 30 days immersion. The results also showed that potassium carbonate–PZ solution caused the least change in membrane wettability. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45543.
Enabling Process Intensification by 3 D Printing of Catalytic Structures
Authors: Konarova Muxina , Aslam Waqas , Ge Lei , Ma Qing , Tang Fengqiu , Rudolph Victor , Beltramini Jorge Norberto 
Published: July 2017

AbstractSmall‐scale, intensified chemical reactors (i.e., process intensification) mediated by structured catalysts substantially diminishes the advantages of large‐scale gas‐to‐liquid (transport fuels) process plants and can be realized at low capital costs, minimum energy consumption, and zero/small CO2 footprints. Current structured‐catalysts approaches are complex and expensive; therefore, simple methods are crucial that are capable of depositing a desired geometry of catalysts into engineered channels. Herein, we developed printable composition by incorporating nickel and molybdenum ions into water‐soluble PVA and starch; the subsequent pyrolysis of organic compounds resulted into three‐dimensional carbon scaffold with micro/macro interconnected pores (dpore, 6.5 Å; dpore, 100 μm) containing up to 25 wt % catalyst loading. 2 D (TEM, SEM) and 3D (X‐ray computed tomography) microstructural analyses and catalytic tests (conversion of syngas to alcohols) were performed for 3 D printed catalysts and compared with conventional pelleted catalysts. At a high feed flow rate (6000 h−1), CO conversion is rapidly reduced to 16 mol % for pelleted catalysts, whereas 3 D printed catalysts converted 35 mol % of CO, with the same catalyst loading.
New Multiresponsive Chromic Soft Materials: Dynamic Interconversion of Short 2,7‐Dicyanomethylenecarbazole‐Based Biradicaloid and the Corresponding Cyclophane Tetramer
Authors: Wang Deliang , Capel Ferrón Cristina , Li Jie , Gámez‐Valenzuela Sergio , Ponce Ortiz Rocio , López Navarrete Juan T. , Hernández Jolín Víctor , Yang Xiaodi , Peña Álvarez Miriam , García Baonza Valentín , Hartl František , Ruiz Delgado M. Carmen , Li Hongxiang 
Published: July 2017

AbstractThis work reports on a quinodimethane‐type molecule, 2,7‐dicyanomethylene‐9‐(2‐ethylhexyl)carbazole (1), one of the shortest π‐conjugated biradicaloids reported to be stable in solution under ambient conditions. This carbazole‐based quinoidal precursor is able to form a macrocyclic σ‐bonded tetramer (2). The resolved single‐crystal X‐ray structure of tetramer 2 shows that four molecules of 1 are linked together through four long (CN)2C−C(CN)2 bonds (1.631 Å) resulting from coupling of the unpaired electrons in biradicaloid 1. Dynamic interconversion between monomer 1 and cyclophane tetramer 2 is achieved by reversible cleavage and recovery of the four (CN)2C−C(CN)2 bonds upon soft external stimuli (light absorption, temperature and pressure), which is accompanied by significant color changes. These novel photo‐, thermo‐, and mechanochromic properties expand the versatility of π‐conjugated biradicaloid compounds as novel functional materials that, in combination with spin chemistry and dynamic covalent chemistry, can be relevant in molecular machines, sensors, and switches.
Chiral Sulfur Functional Groups as Definers of the Chirality at the Metal in Ir and Rh Half‐Sandwich Complexes: A Combined CD/X‐ray Study
Authors: Avello Marta G. , Frutos María , de la Torre María C. , Viso Alma , Velado Marina , de la Pradilla Roberto Fernández , Sierra Miguel A. , Gornitzka Heinz , Hemmert Catherine 
Published: July 2017

AbstractMesoionic carbenes (MICs) derived from triazolium salts that contain chiral sulfoxide or sulfoximine functional groups were used to construct enantiopure chiral‐at‐metal IrIII and RhIII half‐sandwich complexes through the synthetic sequence of MIC complexation/C−H aromatic activation. The process was efficient and diastereoselective for the formation of enantiopure five‐membered metallacycles. The use of the enantiomers of the chiral sulfur groups allowed us to prepare complexes that had opposite configurations at the metal center. Complete retention of the configuration at the metal center was observed during the formation of cationic IrIII complexes and upon insertion of alkynes into the IrIII−C bond, as demonstrated by a combined circular dichroism/X‐ray study. These results point to a vicinal‐assisted SN1‐like mechanism.
Disulfide Bond Mimetics: Strategies and Challenges
Authors: Gori Alessandro , Gagni Paola , Rinaldi Silvia 
Published: July 2017

AbstractThe activity profile of many biologically relevant proteins and peptides often relies on a precise 3D structural organization. In this context, disulfide bonds are natural covalent constraints that play a key role in driving and stabilizing the folding pattern of these molecules. Despite its prominent significance as structural motif, the disulfide bond itself is inherently unstable under physiological conditions, posing a major limit to the use and development of disulfide‐rich peptides and proteins as molecular tools and drug lead compounds. To tackle this restriction, disulfide engineering with stable functional analogues has arisen a considerable interest. Here, the most popular approaches to disulfide replacement are reviewed and discussed with particular emphasis on advantages and limitations under both functional and synthetic perspectives.
Highly Diastereo‐ and Enantioselective Synthesis of Tetrahydro‐5H‐Indolo[2,3‐b]quinolines through Copper‐Catalyzed Propargylic Dearomatization of Indoles
Authors: Shao Wen , You Shu‐Li 
Published: July 2017

AbstractThe first copper‐catalyzed intermolecular asymmetric propargylic dearomatization/annulation cascade sequence of indoles via a copper‐allenylidene amphiphilic intermediate has been achieved. This protocol provides a direct asymmetric synthetic method for the preparation of tetrahydro‐5H‐indolo[2,3‐b]quinolines, the core structure of indole alkaloids communesins A–H and perophoramidine. This method features excellent yields, high diastereoselectivity (up to >19:1 d.r.) and enantioselectivity (up to 94 % ee), mild conditions and wide substrate scope.