bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction Study and Reactivity of ZrIV‐Substituted Wells–Dawson Polyoxometalate towards Hydrolysis of Peptide Bonds in Surfactant Solutions
Authors: Quanten Thomas , Shestakova Pavletta , Van Den Bulck Dries , Kirschhock Christine , Parac‐Vogt Tatjana N. 
Published: February 2016

AbstractThe interaction between the 1:2 ZrIV:Wells–Dawson complex, K15H[Zr(α2‐P2W17O61)2] (1), and a range of surfactants was studied in detail with the aim of developing metal‐substituted POMs as potential artificial proteases for membrane proteins. The surfactants include the positively charged cetyl(trimethyl)ammonium bromide (CTAB), the negatively charged sodium dodecyl sulfate (SDS), the neutral Triton X‐100 (TX‐100), and zwitterionic 3‐[dodecyl(dimethyl)ammonio]‐1‐propanesulfonate (Zw3‐13) and 3‐[dimethyl(3‐{[(3α,5β,7α,12α)‐3,7,12‐trihydroxy‐24‐oxocholan‐24‐yl]amino}propyl)ammonio]‐1‐propanesulfonate (CHAPS). A combination of multinuclear 1H, 13C, and 31P NMR spectroscopy, 1H diffusion‐ordered NMR spectroscopy (1H DOSY), and nuclear Overhauser effect spectroscopy (NOESY) was used to examine the interaction between 1 and each surfactant on the molecular level. Cationic surfactant CTAB caused precipitation of 1 due to strong electrostatic interactions, while the anionic SDS and neutral TX‐100 surfactants did not exhibit any interaction at neutral pD. 1H DOSY NMR spectroscopy indicated an interaction between 1 and zwitterionic surfactants Zw3‐12 and CHAPS, which occurs via the positively charged ammonium group in the surfactant molecule. In the presence of anionic, neutral, and zwitterionic surfactants, 1 preserves its catalytic activity towards the hydrolysis of the peptide bond in the dipeptide glycyl‐l‐histidine (GH). The fastest hydrolysis was observed at pD 7.0 and could be rationalized by taking into account pD‐dependent speciation of 1 and coordination properties of GH.
Stable Crystalline Forms of Na Polysulfides: Experiment versus Ab Initio Computational Prediction
Authors: Mali Gregor , Patel Manu U. M. , Mazaj Matjaž , Dominko Robert 
Published: February 2016

AbstractFor the design of light‐metal–sulfur batteries and for the understanding of their performance, knowledge on the stable crystalline polysulfides is very important. We confronted experimental and ab initio crystal structure prediction studies on the stability of Na polysulfides. The selected evolutionary‐based structure‐prediction algorithm was able to quickly and correctly predict the thermodynamically stable crystalline forms of Na polysulfides with small unit cells. For Na polysulfides with large unit cells, the algorithm correctly proposed short unbranched polysulfide chains to be energetically favorite structural motifs, but could not find proper three‐dimensional structures in the limited number of generations. Experimentally, the polysulfides were studied by X‐ray diffraction and 23Na solid‐state NMR spectroscopy. Complemented by calculations of the isotropic chemical shifts and quadrupolar coupling constants, NMR spectroscopy proved to be an excellent tool for the examination of Na polysulfides, because it allowed easy distinction and quantification of components in the samples.
A Supramolecular Chiral Auxiliary Approach: “Remote Control” of Stereochemistry at a Hierarchically Assembled Dimeric Helicate
Authors: Van Craen David , Albrecht Markus , Raabe Gerhard , Pan Fangfang , Rissanen Kari 
Published: February 2016

AbstractDimeric hierarchically‐assembled titanium(IV) helicates are in solvent‐dependent equilibrium with the corresponding monomers. Statistically formed mixtures of such complexes bearing chiral stereocontrolling ligands and achiral diene‐substituted ligands show high diastereoselectivity and reasonable enantioselectivity in the Diels–Alder reaction with maleimides if the reaction proceeds with the dimer but not with the monomer. Thus, solvent dependent switching between the monomer and dimer enables on/off switching of the enantioselectivity.
Synthesis of Triarylpyridines in Thiopeptide Antibiotics by Using a C−H Arylation/Ring‐Transformation Strategy
Authors: Amaike Kazuma , Itami Kenichiro , Yamaguchi Junichiro 
Published: February 2016

AbstractWe have described a C−H arylation/ring‐transformation strategy for the synthesis of triarylpyridines, which form the core structure of thiopeptide antibiotics. This synthetic method readily gave 2,3,6‐triarylpyridines in a regioselective manner by a two‐phase approach: C−H arylation (a nickel‐catalyzed decarbonylative Suzuki–Miyaura cross‐coupling and decarbonylative C−H coupling for the synthesis of 2,4‐diaryloxazoles) and ring transformation ([4+2] cycloaddition of 2,4‐diaryloxazoles with (hetero)arylacrylic acids). To showcase these methods, we have accomplished the formal synthesis of thiopeptide antibiotics GE2270 s and amythiamicins.
Platinum‐Catalyzed Friedel–Crafts‐Type C−H Coupling–Allylic Amination Cascade to Synthesize 3,4‐Fused Tricyclic Indoles
Authors: Suzuki Yuta , Tanaka Yuito , Nakano Shun‐ichi , Dodo Kosuke , Yoda Natsumi , Shinohara Ken‐ichi , Kita Kazuko , Kaneda Atsushi , Sodeoka Mikiko , Hamada Yasumasa , Nemoto Tetsuhiro 
Published: February 2016

AbstractA novel platinum‐catalyzed cascade cyclization reaction was developed by intramolecular Friedel–Crafts‐type C−H coupling of aniline derivatives with a propargyl carbonate unit‐allylic amination sequence. Treatment of various propargyl carbonates tethered to meta‐aniline derivatives with a Pt(dba)3/DPEphos catalyst system afforded the corresponding 3,4‐fused tricyclic 3‐alkylidene indolines in 42–99 % yield, which were transformed into 3,4‐fused indole derivatives by reaction with trifluoroacetic acid. The reaction products exhibited antiproliferative activities against cancer cells, but not normal cells, revealing the potential usefulness of this reaction for medicinal chemistry.
To Tattoo or not to Tattoo
Authors: Petersen Henrik , Roth Klaus 
Published: February 2016

AbstractTätowierungen sind ein häufig geschätzter, häufig verdammter Teil unseres kulturellen Erbes. In den letzten Jahrzehnten war ein erstaunliches Comeback zu beobachten. Tätowierungen wurden Mode und heute haben etwa 100 Millionen Europäer mindestens eine Tätowierung. Den meisten Trägern sind weder die damit verbundenen gesundheitlichen Risiken noch die teilweise bestehenden Mängel in der Ausbildung der Tätowierer, den hygienischen Arbeitsbedingungen und der Qualität der verwendeten Farben bewusst. Um den ganzen Tätowierungsprozess kritisch bewerten zu können, wird die Einbringung und das Schicksal der Farben in der Haut eines Tätowierten aus chemischer Sicht analysiert.
Leistungsfähige Materialien und Ressourcen‐effiziente Lösungen sind gefragt
Authors: Schubert Ulrich 
Published: February 2016

AbstractDie Auffächerung der Chemie in Teilgebiete ist in den vergangenen Jahrzehnten sehr breit geworden und reflektiert unter anderem die zunehmende Wechselwirkung mit angrenzenden Gebieten aus Wissenschaft und Technik. Diese Entwicklung birgt aber auch die große Gefahr in sich, dass sich “chemische Subkulturen” bilden, die untereinander den Kontakt verlieren. Eine Rückbesinnung an das gemeinsame Zentrum hat nichts mit Nostalgie zu tun, sondern ist vonnöten um den spezifischen Denkweisen der Chemie und deren Herangehensweisen zur Lösung von Problemen Geltung zu verschaffen. Hier hat Chemie in unserer Zeit eine wichtige Funktion, vermittelt sie doch, unter Verzicht auf “Fachchinesisch”, Nicht‐Spezialisten grundlegende Einblicke in die einzelnen Unter‐Disziplinen.
Das Genom
Authors: Groß Michael 
Published: February 2016

Abstract15 Jahre nach der Erstsequenzierung des menschlichen Genoms wissen wir, dass es weit weniger Gene gibt als erwartet, und dass die Gensequenzen im Humangenom nicht die Antworten auf die offenen Fragen der Medizin liefern. Das hat die Aufmerksamkeit auf komplexe Zusammenhänge im Umfeld der Gene gelenkt, wie regulatorische Elemente, Stichwort Epigenetik, und die ehemalige Junk‐DNA, die keineswegs Müll ist, sondern auf komplexe und unerwartete Weise mit vielfältigen Funktionen der Zelle wechselwirkt. In dieser Serie werden deshalb die Komplexität und Netzwerk‐Eigenschaft der Chemie des Lebens im Mittelpunkt stehen. In jeder Ausgabe wollen wir einen Knotenpunkt des Netzwerks näher betrachten und dann erkennen, wie dieser mit anderen Funktionen zusammenhängt.
Natural yellow and red Fe‐based geomaterials from the Lessini mountains in Veneto, Italy: A review
Authors: Cavallo Giovanni , Riccardi Maria Pia , Zorzin Roberto 
Published: February 2016

AbstractThe possibility that natural earths from Lessini Mountains were used in archaeological and artistic contexts is an intriguing question; nevertheless, a first attempt in provenance studies was made only recently. This contribution discusses critically the bibliographic records following a chronological perspective in the light of the most recent scientific research in order to propose the state of the art on the evolution of the knowledge of yellow and red earths in the Western sector of the Lessini Mountains. © 2016 Wiley Periodicals, Inc. Col Res Appl, 41, 221–225, 2016
Kinetics of Reactive Modules Adds Discriminative Dimensions for Selective Cell Imaging
Authors: Quérard Jérôme , Le Saux Thomas , Gautier Arnaud , Alcor Damien , Croquette Vincent , Lemarchand Annie , Gosse Charlie , Jullien Ludovic 
Published: February 2016

AbstractLiving cells are chemical mixtures of exceptional interest and significance, whose investigation requires the development of powerful analytical tools fulfilling the demanding constraints resulting from their singular features. In particular, multiplexed observation of a large number of molecular targets with high spatiotemporal resolution appears highly desirable. One attractive road to address this analytical challenge relies on engaging the targets in reactions and exploiting the rich kinetic signature of the resulting reactive module, which originates from its topology and its rate constants. This review explores the various facets of this promising strategy. We first emphasize the singularity of the content of a living cell as a chemical mixture and suggest that its multiplexed observation is significant and timely. Then, we show that exploiting the kinetics of analytical processes is relevant to selectively detect a given analyte: upon perturbing the system, the kinetic window associated to response read‐out has to be matched with that of the targeted reactive module. Eventually, we introduce the state‐of‐the‐art of cell imaging exploiting protocols based on reaction kinetics and draw some promising perspectives.
Faster acquisition of symbiotic partner by common mycorrhizal networks in early plant life stage
Authors: Varga Sandra , Kytöviita Minna‐Maarit 
Published: February 2016

AbstractArbuscular mycorrhizal (AM) fungi usually improve plant performance yet our knowledge about their effects on seed germination and early plant establishment is very limited. We performed a factorial greenhouse experiment where the seeds from four low Arctic co‐occurring mycorrhizal herbs (Antennaria dioica, Campanula rotundifolia, Sibbaldia procumbens, and Solidago virgaurea) were germinated alone or in the vicinity of an adult Sibbaldia plant with or without AM fungi; given either as spores or being present in a common mycorrhizal network (CMN). Three different AM fungal species were examined to assess species‐specific differences in symbiont acquisition rate. Of the four plant species investigated, the presence of AM fungi affected seed germination only in Campanula and this effect was dependent on whether the AM fungi were present in the soil as spores or as a CMN. Overall, after germination, developing seedlings showed AM fungal colonization in their roots as soon as 2 d after cotyledon emergence. Our results show that CMN may provide germinating seedlings faster acquisition of the AM fungal partner in comparison to acquisition from spores. Furthermore, there were AM species‐specific differences in the symbiont acquisition rate highlighting the importance of species identity in AM interactions. These findings suggest that while AM fungi may not play a fundamental role during seed germination, plant community composition may be affected by the species‐specific AM fungal effects on seedling establishment and CMN acquisition.
Influence of mineral admixtures on mechanical properties of self‐compacting concrete under elevated temperature
Authors: N Anand , I Antony Godwin , G Prince Arulraj 
Published: February 2016

SUMMARYSelf‐compacting concrete (SCC) is a form of concrete that is capable of flowing into the congested interior of formwork and consolidating under the action of its own weight without segregation and bleeding. In the present investigation, an attempt has been made to study the effect of elevated temperature on mechanical properties of SCC specimens made with different mineral admixtures that were heated from 27 to 900 °C and cooled by air or water. Silica fume, flyash, metakaolin were used as mineral admixtures. Master Glenium was used as superplasticizer, and Glenium Stream 2 was used as viscosity modifying agent. Mechanical properties of the cooled specimens such as compressive strength, tensile strength, flexural strength, and modulus of elasticity were found. Compressive, tensile, and flexural strengths of specimens were found to decrease by 73.18%, 65.05%, and 63.2%, and 85.2%, 83.52%, and 83.56% for the specimens with metakaolin that were heated and cooled by air and water, respectively. Similar reductions were found for the SCC specimens made with silica fume and flyash. Microstructure investigation has been carried out on SCC samples using scanning electron microscope and X‐ray diffraction analytical techniques to understand the effect of temperature on decrease in strength. Copyright © 2016 John Wiley & Sons, Ltd.
A change in social activity affect cognitive function in middle‐aged and older Koreans: analysis of a Korean longitudinal study on aging (2006–2012)
Authors: Choi Young , Park Sohee , Cho Kyoung Hee , Chun Sung‐Youn , Park Eun‐Cheol 
Published: February 2016

ObjectiveTo examine the association between a changes in social activity and cognitive function in Koreans aged 45 years or older.MethodsData were obtained from 6076 participants aged 45 years and older included in the Korean Longitudinal Study of Aging (2006–2012). Cognitive function was measured using the mini‐mental state examination—Korean version (MMSE‐K). Participation in social activities was classified as “consistent participation,” “consistent non‐participation,” “participation to non‐participation,” and “non‐participation to participation.” Linear mixed models were used to investigate the relationship between type of social activity (religious organizations, friendship organizations, leisure/culture/sports clubs, family or school reunion, volunteering work, and political organizations), and cognitive function.ResultsIndividuals who reported “no participation to participation” (b = 0.778, p < 0.0001) and “consistent participation” (b = 0.968, p < 0.0001) were more likely to show reduced cognitive decline than those who reported “consistent non‐participation” (p < 0.0001 for trend). The positive association between cognitive function and consistent participation in religious activities, friendship organizations, and family/school reunions was particularly strong (b = 0.325, p < 0.0001; b = 0.570, p < 0.0001; b = 0.234, p = 0.0004; respectively, versus consistent non‐participation).ConclusionsPromotion of participation in religious organizations, friendship organizations, and family/school reunions (only for older persons) may help preserve cognitive function in individuals aged 45 years or older in Korea. Copyright © 2016 John Wiley & Sons, Ltd.
Structural brain correlates of cognitive and behavioral impairment in MND
Authors: Agosta Federica , Ferraro Pilar M. , Riva Nilo , Spinelli Edoardo G. , Chiò Adriano , Canu Elisa , Valsasina Paola , Lunetta Christian , Iannaccone Sandro , Copetti Massimiliano , Prudente Evelina , Comi Giancarlo , Falini Andrea , Filippi Massimo 
Published: February 2016

AbstractObjectiveTo assess the structural correlates of cognitive and behavioral impairment in motor neuron diseases (MND) using multimodal MRI.MethodsOne hundred one patients with sporadic MND (56 classic amyotrophic lateral sclerosis, 31 upper motor neuron phenotype, and 14 lower motor neuron phenotype) and 51 controls were enrolled. Patients were classified into MND with a pure motor syndrome (MND‐motor) and with cognitive/behavioral symptoms (MND‐plus). Cortical thickness measures and diffusion tensor (DT) metrics of white matter (WM) tracts were assessed. A random forest approach was used to explore the independent role of cortical and WM abnormalities in explaining major cognitive and behavioral symptoms.ResultsThere were 48 MND‐motor and 53 MND‐plus patients. Relative to controls, both patient groups showed a distributed cortical thinning of the bilateral precentral gyrus, insular and cingulate cortices, and frontotemporal regions. In all regions, there was a trend toward a more severe involvement in MND‐plus cases, particularly in the temporal lobes. Both patient groups showed damage to the motor callosal fibers, which was more severe in MND‐plus. MND‐plus patients also showed a more severe involvement of the extra‐motor WM tracts. The best predictors of executive and non‐executive deficits and behavioral symptoms in MND were diffusivity abnormalities of the corpus callosum and frontotemporal tracts, including the uncinate, cingulum, and superior longitudinal fasciculi.ConclusionsCortical thinning and WM degeneration are highly associated with neuropsychological and behavioral symptoms in patients with MND. DT MRI metrics seem to be the most sensitive markers of extra‐motor deficits within the MND spectrum. Hum Brain Mapp 37:1614‐1626, 2016. © 2016 Wiley Periodicals, Inc.
Indications, reconstructive techniques, and results for total glossectomy
Authors: Mazarro Alejandro , de Pablo Alba , Puiggròs Carolina , Velasco Mª Mercedes , Saez Manel , Pamias Jorge , Bescós Coro 
Published: February 2016

AbstractBackgroundThe best treatment for advanced tongue tumors remains controversial. Total glossectomy with laryngeal preservation is considered a feasible option, despite its morbidity.MethodsA retrospective analysis of 12 total glossectomies with laryngeal preservation was performed in order to assess the available reconstruction techniques and analyze survival and functional outcomes.ResultsOne‐year overall survival (OS) and disease‐free survival (DFS) rates were 58.3% and 33.3%, respectively, both dropping to 25% after 3 years. Permanent gastrostomy was necessary in 10 patients, although videofluoroscopy revealed adequate tolerance to liquids. Speech intelligibility was satisfactory in 50% of the patients and severely impaired in the remaining 50%.ConclusionLaryngeal preservation in the context of advanced tumors of the tongue without supraglottic invasion carried similar oncologic results to total glossectomy with laryngectomy, but offers a better phonatory function. However, it is usually associated with a higher gastrostomy dependency ratio. A scrupulous selection of candidates is mandatory. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2004–E2010, 2016
Biodegradable Self‐Assembled Nanoparticles of Galactose‐Containing Amphiphilic Triblock Copolymers for Targeted Delivery of Paclitaxel to HepG2 Cells
Authors: Wang Tieshi , Tang Xinde , Han Jingtian , Ding Yuanyuan , Guo Wenjuan , Pei Meishan 
Published: February 2016

Biodegradable self‐assembled polymeric nanoparticles (NPs) composed of poly(6‐O‐methacryloyl‐D‐galactopyranose)‐b‐poly(L‐lactide)‐b‐poly(6‐O‐methacryloyl‐D‐galactopyranose) (PMAGP‐b‐PLA‐b‐PMAGP) are prepared as carriers for the hydrophobic anticancer drug paclitaxel (PTX), to achieve target delivery to hepatoma cells. PTX can be encapsulated by the NPs with various molar ratios of L‐lactide (LA) and 6‐O‐methacryloyl‐D‐galactopyranose (MAGP) during the process of self‐assembly, and the resulting NPs exhibit high drug loading efficacy and substantial stability in aqueous solution. The size, size distribution, and morphology of the NPs are characterized using a Zetasizer Nano ZS and transmission electron microscopy. The hemolysis assay and cell cytotoxicity assay indicate that the polymeric NPs are biocompatible and non‐toxic. The cellular uptake assay demonstrates that the galactose‐containing NPs can be selectively recognized and subsequently accumulate in HepG2 cells. All of these results demonstrate that galactose‐containing polymeric NPs are potential carriers for hepatoma‐targeted drug delivery and liver cancer therapy in clinical medicine.
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A Supramolecular Approach toward Bioinspired PAMAM‐Dendronized Fusion Toxins
Authors: Kuan Seah Ling , Förtsch Christina , Ng David Yuen Wah , Fischer Stephan , Tokura Yu , Liu Weina , Wu Yuzhou , Koynov Kaloian , Barth Holger , Weil Tanja 
Published: February 2016

Nature has provided a highly optimized toolbox in bacterial endotoxins with precise functions dictated by their clear structural division. Inspired by this streamlined design, a supramolecular approach capitalizing on the strong biomolecular (streptavidin (SA))–biotin interactions is reported herein to prepare two multipartite fusion constructs, which involves the generation 2.0 (D2) or generation 3.0 (D3) polyamidoamine‐dendronized transporter proteins (dendronized streptavidin (D3SA) and dendronized human serum albumin (D2HSA)) non‐covalently fused to the C3bot1 enzyme from Clostridium botulinum, a potent and specific Rho‐inhibitor. The fusion constructs, D3SA‐C3 and D2HSA‐C3, represent the first examples of dendronized protein transporters that are fused to the C3 enzyme, and it is successfully demonstrated that the C3 Rho‐inhibitor is delivered into the cytosol of mammalian cells as determined from the characteristic C3‐mediated changes in cell morphology and confocal microscopy. The design circumvents the low uptake of the C3 enzyme by eukaryotic cells and holds great promise for reprogramming the properties of toxin enzymes using a supramolecular approach to broaden their therapeutic applications.
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Universality in Branching Frequencies and Molecular Dimensions during Hyperbranched Polymer Formation: Step Polymerization of AB2 Type Monomer with Equal Reactivity
Authors: Tobita Hidetaka 
Published: February 2016

Hyperbranched polymer formation during step polymerization of AB2 type monomer with equal reactivity of two B's is investigated theoretically, focusing the attention to the degree of branching (DB) and the mean square radius of gyration for the unperturbed chains, . It is found that the DB‐value at large degree of polymerization (P) limit, = 0.5 is unchanged during the whole course of polymerization. The average value of having the same P is invariant throughout the polymerization. The universal curve between and P agrees perfectly with that for the self‐condensing vinyl polymerization (SCVP), another method to synthesize hyperbranched polymers, when the reactivity ratio for SCVP, rSCVP, is 2.589 that gives = 0.5. The power law, is found for large values of P.
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