bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nobler than the Noblest: Noncubic Gold Microcrystallites
Authors: Mettela Gangaiah , Kouser Summayya , Sow Chaitali , Pantelides Sokrates T. , Kulkarni Giridhar U. 
Published: May 2018

AbstractConventional gold comprising the cubic lattice is universally known for its stability. However, well known to chemists and metallurgists, this nobility is challenged by reagents such as aqua regia, which dissolve gold to form a salt solution. Among metals, mercury blends with gold to form amalgam, otherwise transition metals such as copper tend to interact with gold surfaces in electrochemical media. Herein, we report a combined experimental and theoretical investigation of the stability of Au microcrystallites bearing unconventional crystal lattices that exhibit enhanced stability towards Hg and aqua regia and practically no interaction with Cu during electroless plating. The unconventional gold is undoubtedly nobler.
Synthesis and Biological Evaluation of the Antimicrobial Natural Product Lipoxazolidinone A
Authors: Mills Jonathan J. , Robinson Kaylib R. , Zehnder Troy E. , Pierce Joshua G. 
Published: May 2018

AbstractNatural products have historically been a major source of antibiotics and therefore novel scaffolds are constantly of interest. The lipoxazolidinone family of marine natural products, with an unusual 4‐oxazolidinone heterocycle at their core, represents a new scaffold for antimicrobial discovery; however, questions regarding their mechanism of action and high lipophilicity have likely slowed follow‐up studies. Herein, we report the first synthesis of lipoxazolidinone A, 15 structural analogues to explore its active pharmacophore, and initial resistance and mechanism of action studies. These results suggest that 4‐oxazolidinones are valuable scaffolds for antimicrobial development and reveal simplified lead compounds for further optimization.
Directed Remote Lateral Metalation: Highly Substituted 2‐Naphthols and BINOLs by In Situ Generation of a Directing Group
Authors: Patel Jignesh J. , Laars Marju , Gan Wei , Board Johnathan , Kitching Matthew O. , Snieckus Victor 
Published: May 2018

AbstractA general synthesis of highly substituted 2‐naphthols based on a new carbanionic reaction sequence is demonstrated. The reaction exploits the dual nature of lithium bases consisting of consecutive ring opening of readily available coumarins with either LiNEt2 or LiNiPr2 into Z‐cinnamamides, thus generating a directing group in situ and allowing, by conformational freedom, a lateral directed remote metalation for ring closure to give the aryl 2‐naphthols in good to excellent yields. These transformations can be combined to provide a more efficient one‐pot process. Mechanistic insight into the remote lateral metalation step, demonstrating the requirement of Z‐cinnamamide, is described. Application of this methodology to the synthesis of highly substituted 3,3′‐diaryl BINOL ligands is also reported.
Nano‐Saturn: Experimental Evidence of Complex Formation of an Anthracene Cyclic Ring with C60
Authors: Yamamoto Yuta , Tsurumaki Eiji , Wakamatsu Kan , Toyota Shinji 
Published: May 2018

AbstractAn anthracene cyclic hexamer was synthesized by the coupling reaction as a macrocyclic hydrocarbon host. This disk‐shaped host included a C60 guest in 1:1 ratio to form a Saturn‐type supramolecular complex in solution and in crystals. X‐ray analysis unambiguously revealed that the guest molecule was accommodated in the middle of the host cavity with several CH⋅⋅⋅π contacts. The association constant Ka determined by NMR titration measurements was 2.3×103 L mol−1 at 298 K in toluene. The structural features and the role of CH⋅⋅⋅π interactions are discussed with the aid of DFT calculations.
Ab Initio Emulsion Atom‐Transfer Radical Polymerization
Authors: Lorandi Francesca , Wang Yi , Fantin Marco , Matyjaszewski Krzysztof 
Published: May 2018

AbstractStable latexes of poly(meth)acrylates with predetermined molecular weights, narrow molecular‐weight distributions, and controlled architecture were prepared by true ab initio emulsion atom‐transfer radical polymerization. Water‐soluble (macro)initiators in combination with a hydrophilic catalyst, Cu/tris(2‐pyridylmethyl)amine, initiated the polymerization in the aqueous phase. The catalyst strongly interacted with the surfactant sodium dodecyl sulfate (SDS), thereby tuning the polymerization within nucleated hydrophobic polymer particles. Long‐term stable latexes were obtained, even with SDS loading below 3 wt % relative to monomer. Block and gradient copolymers were prepared in situ. The reaction volume and solid content were successfully increased to 100 mL and 40 vol %, respectively, thus suggesting facile scale‐up of this technique. The proposed setup could be integrated in existing industrial plants used for emulsion polymerization.
trans‐Carbocarbonation of Internal Alkynes through a Formal anti‐Carbopalladation/C−H Activation Cascade
Authors: Reding Andreas , Jones Peter G. , Werz Daniel B. 
Published: May 2018

AbstractAn intramolecular Pd‐catalyzed cascade reaction is presented that consists of a formal anti‐carbopalladation of a C−C triple bond followed by C−H activation. As a result, oligocyclic ring systems with an embedded tetrasubstituted double bond are formed. The key to success in affording the trans geometry of the emerging double bond are alkyne units with residues that must not undergo β‐hydride elimination (e.g., t‐butyl or silyl groups). Silyl groups proved to be a perfect handle to further convert the tetrasubstituted alkenes. The evaluation of kinetic data with a deuterium‐labeled compound and X‐ray analyses of trapped intermediates provided additional insight into the catalytic cycle.
Polymer complexes. LXXI. Spectroscopic studies, thermal properties, DNA binding and antimicrobial activity of polymer complexes
Authors: Diab M.A. , El‐Sonbati A.Z. , Morgan Sh.M. , El‐Mogazy M.A. 
Published: May 2018

Polymer complexes of Co(II), Ni(II), Mn(II), Cr(III) and Cd(II) were prepared by the reaction of 3‐allyl‐5‐[(4‐nitrophenylazo)]‐2‐thioxothiazolidine‐4‐one (HL) with metal ions. The structure of polymer complexes was characterized by elemental analysis, IR, UV–Vis spectra, X‐ray diffraction analysis, magnetic susceptibility, conductivity measurements and thermal analysis. Reaction of HL with Co(II), Ni(II), Mn(II), Cr(III) and Cd(II) ions (acetate or chloride) give polymer complexes (1–5) with general stoichiometric [M(L)(O2CCH3)(H2O)2]n (where L = anionic of HL and M = Co(II) (1) or Ni(II) (2)), [Mn(HL)2(OCOCH3)2]n (3), [Cr(L)2(Cl)(H2O)]n (4) and [Cd(HL)(O2CCH3)2]n (5). The value of HOMO–LUMO energy gap (ΔE) for forms (A‐C) of monomer (HL) is 2.529, 2.296 and 2.235 eV, respectively. According to ΔE value, compound has minimum ΔE is the more stable, so keto hydrazone form (C) is more stable than the other forms (azo keto form (A), azo enol form (B)). The interaction between HL, polymer complexes of Co(II), Ni(II), Mn(II), Cr(III) and Cd(II) with Calf thymus DNA showed hypochromism effect. The HL and its polymer complexes were tested against some bacterial and fungal species. The results showed that the Cr(III) polymer complex (4) has more antibacterial activity than HL and polymer complexes (1–3 and 5) against Bacillus subtilis, Staphylococcus aureus and Salmonella typhimurium.
Volatiles and Tendency of Radical Formation of Cold‐Pressed Brazil Nut Oil During Ambient Storage
Authors: Sartori Alan G. de O. , Sampaio Geni R. , Bastos Deborah H. M. , Regitano d'Arce Marisa A. B. , Skibsted Leif H. 
Published: May 2018

AbstractCold‐pressed Brazil nut oil (BNO) is a value‐added nontimber forest coproduct of market interest, despite the lack of knowledge about its ambient storage stability. The objective of the present study was to investigate oxidative changes in BNO stored in clear and brown glass bottles under retail conditions with a focus on monitoring for the first time the formation of volatile aroma compounds (VAC), the depletion of tocopherol analogs, and the tendency of radical formation. VAC, whose formation continuously increased and correlated with storage time, were detected using headspace‐solid‐phase microextraction‐gas chromatography–mass spectrometry. Depletion of tocopherols was more pronounced for the oil stored in clear glass bottles and the content loss was higher for alpha‐tocopherol than for gamma‐tocopherol. Furthermore, the tendency of radical formation was detected using a spin‐trapping electron spin resonance spectroscopy method, which was demonstrated to be a simpler, faster, and less sample‐demanding tool to monitor the oxidative status of BNO stored under retail conditions and its results significantly correlated with those obtained using traditional methods for the determination of primary oxidation products. However, the simultaneous measurement of key off‐flavor volatiles is recommended for samples with unknown history.
Sonocrystallization of a Tristearin‐Free Fat
Authors: Kadamne Jeta V. , Moore Maria , Akoh Casimir C. , Martini Silvana 
Published: May 2018

AbstractThe objective of this study was to fractionate a purified interesterified fat to eliminate tristearin (SSS) and to evaluate the crystallization behavior of the tristearin‐free fat. The fractionated sample was crystallized with and without the application of high‐intensity ultrasound (HIU) by supercooling the sample at 2 °C. In the absence of SSS, the crystallization process was driven by low‐melting‐point triacylglycerols (TAG) such as OSS and OOS (O, oleic; S, stearic acid). There were no differences observed in the crystallinity in the sample based on the solid fat content (P > 0.05) along with any microstructural differences. In addition, an increase in the enthalpy of melting was observed upon sonication, indicating higher crystallinity (P < 0.05). Stronger intramolecular forces were formed in the sonicated samples as evidenced by increased viscoelastic parameters such as the elastic modulus (G′) and storage modulus (G″) (P < 0.05). G′ values increased from 138.25 ± 41.30 to 939.73 ± 277.45 Pa while the G″ values increased from 39.15 ± 8.98 to 149.77 ± 16.00 Pa (P < 0.05). Change in viscosity was not observed as a consequence of sonication (P > 0.05). This study showed that HIU was effective in changing the crystallization behavior of SSS‐free fats with low‐melting TAG.
Synthesis of waterborne polyurethane containing alkoxysilane side groups: Study on spacer linkages
Authors: Li Qi , Ye Jun , Qiu Teng , Guo Longhai , He Lifan , Li Xiaoyu 
Published: May 2018

ABSTRACTEnvironmentally friendly waterborne polyurethanes (WPUs) modified by moisture‐curable alkoxysilane have been much studied nowadays. In this work, a new diol‐bearing pendant urea‐propyl trimethoxysilane (APD‐Si) was synthesized and used as the chain extender in the preparation of a silicone‐modified WPU dispersion. Both the formation of hybrid networks based on the condensation of trimethoxysilane groups and the enhanced microphase separation of the hard and soft segments have been found to rely on the strong hydrogen‐bonding capability of the urea‐containing spacers, which link the alkoxysilane groups with the backbone of WPU. Because of the synergism of chemically bonded silsesquioxane and physically hydrogen bonded hard domains serving as crosslinking points, the mechanical properties of the hybrid films of WPU are improved, especially the modulus and yield strength. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46628.
Laser transmission welding of poly(lactic acid) and polyamide66/sepiolite nanocomposites
Authors: Navas‐Martos Francisco J. , Yebra‐Rodríguez África , La Rubia M. Dolores 
Published: May 2018

ABSTRACTInfluence of sepiolite nanoclay on the properties of the resulting join between poly(lactic acid) (PLA) and different Polyamide66 (PA66)/nanoclay nanocomposites was studied in this work. Six different polymer nanocomposites based on PA66 were manufactured through a melt compounding process by adding a fixed 1.64 wt % of a commercial IR absorber additive and the respective weight percentages of sepiolite to the polymer matrix. Several nanocomposite/PLA joints were finally performed by means of the transmission laser welding technology and the resulting weldings were characterized in terms of mechanical properties by performing peeling and shearing tests. Furthermore, both welded and mechanically tested samples were also analyzed by scanning electron microscopy in order to study the morphology of the weld seam. The results of the performed tests show that the addition of sepiolite to the PA66 improves the welding performance only in those cases in which the percentage of sepiolite of the nanocomposites is higher than 5 wt %. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2018,135, 46638.
Long‐term studies on PVC membranes used in tunnels
Authors: Londschien Martin , Bonnet Martin 
Published: May 2018

ABSTRACTBuilding tunnels places very high demands on the durability of all materials used. However, up to now only very few real long‐term studies on waterproofing membranes used in tunnels have been carried out. Samples from soft poly(vinyl chloride) membranes with diverse ages of over 40 years were taken during refurbishment programs to ensure safety in various Swiss tunnels. The results of gel permeation chromatography as well as measurements of the plasticizer and gel content showed that all of the membranes have very low polymer degradation or, respectively, none detectable crosslinking of the polymer. The main change determined was the decrease in plasticizer content and the resulting increase in stiffness of the membranes. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46689.
Oxygenates from the Electrochemical Reduction of Carbon Dioxide
Authors: Feng Guanghui , Chen Wei , Wang Baiyin , Song Yanfang , Li Guihua , Fang Jianhui , Wei Wei , Sun Yuhan 
Published: May 2018

AbstractElectrochemical reduction of carbon dioxide (CO2) driven by renewable electricity to give chemicals and fuels is considered an ideal approach that can alleviate both carbon emission and energy tension stress. High‐value chemicals such as oxygenates can be effectively produced from the electroreduction of CO2, and this is highly attractive to promote the economy and applicability of CO2 utilization. This review focuses on recent advancements in the electrochemical reduction of CO2 to formic acid, methanol, ethanol, acetic acid, and other oxygenates. The principles of the process, influencing factors, and typical catalysts are summarized. On the basis of the aforementioned discussions, we present future prospects for further development of the electroreduction of CO2 to oxygenates.
Atomic and Molecular Layer Deposition for Superior Lithium‐Sulfur Batteries: Strategies, Performance, and Mechanisms
Authors: Sun Qian , Lau Kah Chun , Geng Dongsheng , Meng Xiangbo 
Published: May 2018

AbstractLithium‐sulfur (Li−S) batteries hold great promise for powering future electric vehicles, given their high theoretical specific energy of 2600 Wh/kg and low cost. However, the commercialization of Li−S batteries is being hindered by several serious technical challenges including the corrosion of lithium metal anodes, the formation of lithium dendrites, the shuttle effect of lithium polysulfides, the decomposition of electrolyte, and low conductivity of sulfur and lithium sulfide. In the past decade, atomic layer deposition (ALD) as a new research thrust has been demonstrated to be a very effective technique in dramatically improving the performance of lithium‐ion batteries (LIBs), featuring many unique advantages in fabricating sub‐nano to nanoscale inorganic films. Stimulated by ALD's benefits, recently more and more research efforts have been reported in ALD for addressing the technical issues of Li−S batteries and show very promising outcomes. Analogous to ALD, molecular layer deposition (MLD) is a thin‐film technique exclusively for polymeric films. Some of the latest studies have uncovered that MLD is an alternative tool for tackling the challenges of Li−S batteries with exceptional effectiveness. In this review, for the first time, we systematically summarized the progresses of both ALD and MLD in developing superior Li−S batteries, covering their technical strategies, resulting performance, and the underlying mechanisms. In terms of the functionalities of ALD and MLD in Li−S batteries, we focus our discussion in two main complementary aspects: (i) surface coatings and (ii) electrode designs.
Reward ignorant modeling of dynamic treatment regimes
Authors: Wallace Michael P. , Moodie Erica E. M. , Stephens David A. 
Published: May 2018

AbstractPersonalized medicine optimizes patient outcome by tailoring treatments to patient‐level characteristics. This approach is formalized by dynamic treatment regimes (DTRs): decision rules that take patient information as input and output recommended treatment decisions. The DTR literature has seen the development of increasingly sophisticated causal inference techniques that attempt to address the limitations of our typically observational datasets. Often overlooked, however, is that in practice most patients may be expected to receive optimal or near‐optimal treatment, and so the outcome used as part of a typical DTR analysis may provide limited information. In light of this, we propose considering a more standard analysis: ignore the outcome and elicit an optimal DTR by modeling the observed treatment as a function of relevant covariates. This offers a far simpler analysis and, in some settings, improved optimal treatment identification. To distinguish this approach from more traditional DTR analyses, we term it reward ignorant modeling, and also introduce the concept of multimethod analysis, whereby different analysis methods are used in settings with multiple treatment decisions. We demonstrate this concept through a variety of simulation studies, and through analysis of data from the International Warfarin Pharmacogenetics Consortium, which also serve as motivation for this work.
Including cannabinoids in the treatment of painful schwannomatosis
Authors: Iorno Vittorio , Roberto Anna , Colantonio Laura Brigitta , Landi Laura , Corli Oscar 
Published: May 2018

A 47‐year‐old man, affected by Schwannomatosis, presented a very severe pain (10/10, NRS) with paroxysmal shooting episodes, allodynia, paresthesia, and dysesthesia; in parallel, the patient had lost weight (from 70 to 49 kg) and experienced fatigue and deep depression. The previous pain prescription, including opioids and antineutopathic drugs, was fully ineffective. We progressively substituted this therapy with 15 drops, 3 times/daily, of THC/CBD in a concentration ratio 5:1, equal to 15 mg of active substance each time, reaching improvement in pain intensity (6/10) and in several other aspects as mood and quality of life
Cortical brain structure and sexual orientation in adult females with bipolar disorder or attention deficit hyperactivity disorder
Authors: Abé Christoph , Rahman Qazi , Långström Niklas , Rydén Eleonore , Ingvar Martin , Landén Mikael 
Published: May 2018

AbstractBackgroundNonheterosexual individuals have higher risk of psychiatric morbidity. Together with growing evidence for sexual orientation‐related brain differences, this raises the concern that sexual orientation may be an important factor to control for in neuroimaging studies of neuropsychiatric disorders.MethodsWe studied sexual orientation in adult psychiatric patients with bipolar disorder (BD) or ADHD in a large clinical cohort (N = 154). We compared cortical brain structure in exclusively heterosexual women (HEW, n = 29) with that of nonexclusively heterosexual women (nHEW, n = 37) using surface‐based reconstruction techniques provided by FreeSurfer.ResultsThe prevalence of nonheterosexual sexual orientation was tentatively higher than reported in general population samples. Consistent with previously reported cross‐sex shifted brain patterns among homosexual individuals, nHEW patients showed significantly larger cortical volumes than HEW in medial occipital brain regions.ConclusionWe found evidence for a sex‐reversed difference in cortical volume among nonheterosexual female patients, which provides insights into the neurobiology of sexual orientation, and may provide the first clues toward a better neurobiological understanding of the association between sexual orientation and mental health. We also suggest that sexual orientation is an important factor to consider in future neuroimaging studies of populations with certain mental health disorders.
Building organizational resilience through sensemaking: The case of climate change and extreme weather events
Authors: Tisch Daniel , Galbreath Jeremy 
Published: May 2018

AbstractResilience to increasingly frequent extreme weather events from climate change is of concern in many industries, especially those in the agricultural sector. This qualitative study utilizes interviews with 38 dairy farmers in New Zealand, observations recorded on site and archival documents to examine retention–enactment–selection sensemaking microprocesses thematically, and to show how sensemaking enables and constrains resilience. We found that farmers have achieved organizational resilience to extreme weather patterns during the decade to 2014 that is benign to belief in climate change; that adaptation to climate change can be anticipatory; and that social relationships in rural communities are instrumental to building organizational resilience. The implication for farmers and policy‐makers is that resilience can be built by local members of rural communities in places that are familiar to them—a phenomenon we introduce as “community sensegiving.” Future research directions using place‐based research approaches and sensemaking concepts to build resilience are offered.
The effect of automatic assessment on novice programming: Strengths and limitations of existing systems
Authors: Ullah Zahid , Lajis Adidah , Jamjoom Mona , Altalhi Abdulrahman , Al‐Ghamdi Abdullah , Saleem Farrukh 
Published: May 2018

AbstractComputer programming is always of high concern for students in introductory programming courses. High rates of failure occur every semester due to lack of adequate skills in programming. No student can become a programmer overnight because such learning requires proper guidance as well as consistent practice with the programming exercises. The role of instructors in the development of students' learning skills is crucial in order to provide feedback on their errors and improve their knowledge accordingly. On the other hand, due to the large number of students, instructors are also overloading themselves to focus on each individual student's errors. To address these issues, researchers have developed numerous Automatic Assessment (AA) systems that not only evaluate the students' programs but also provide instant feedback on their errors as well as abridge the workload of the instructors. Due to the large pool of existing systems, it is difficult to cover each and every system in one study. Therefore, this paper provides a comprehensive overview of some of the existing systems based on the three‐analysis approaches: dynamic, static, and hybrid. Moreover, this paper aims to discuss the strengths and limitations of these systems and suggests some potential recommendations regarding the AA specifications for novice programming, which may help in standardizing these systems.