bluuebunny/crossref_metadata_2025_split huggingface dataset:
Versatile Homoallylic Boronates by Chemo‐, SN2′‐, Diastereo‐ and Enantioselective Catalytic Sequence of Cu−H Addition to Vinyl‐B(pin)/Allylic Substitution
Authors: Lee Jaehee , Torker Sebastian , Hoveyda Amir H. 
Published: December 2016

AbstractA highly chemo‐, diastereo‐ and enantioselective catalytic method that efficiently combines a silyl hydride, vinyl‐B(pin) (pin=pinacolato) and (E)‐1,2‐disubstituted allylic phosphates is introduced. Reactions, best promoted by a Cu‐based complex with a chiral sulfonate‐containing N‐heterocyclic carbene, are broadly applicable. Aryl‐, heteroaryl‐, alkenyl‐, alkynyl‐ and alkyl‐substituted allylic phosphates may thus be converted to the corresponding homoallylic boronates and then alcohols (after C−B bond oxidation) in 46–91 % yield and in up to >98 % SN2′:SN2 ratio, 96:4 diastereomeric ratio and 98:2 enantiomeric ratio. The reasons why an NHC−Cu catalyst is uniquely effective (vs. the corresponding phosphine systems) and the basis for different trends in stereoselectivity are provided with the aid of DFT calculations.
Uterine focal adhesion dynamics during pregnancy in a marsupial (Sminthopsis crassicaudata; Dasyuridae)
Authors: Laird Melanie K. , Turancova Michaela , McAllan Bronwyn M. , Murphy Christopher R. , Thompson Michael B. 
Published: December 2016

ABSTRACTAlterations to the basal attachment points between the epithelium of the uterus and the underlying tissue in early pregnancy affect how easily the epithelium can be invaded by the implanting embryo. Attachment points‐ focal adhesions‐ disassemble to facilitate highly invasive implantation in rats, but species with less invasive implantation, including marsupials, may require different basal alterations for successful pregnancy. Here we used immunofluorescence microscopy and Western blotting to conduct the first study of basal plasma membrane dynamics in the uterus during marsupial pregnancy. We describe localisation patterns of two key anchoring molecules, talin and paxillin, throughout pregnancy in the fat‐tailed dunnart (Sminthopsis crassicaudata; Dasyuridae). Basal staining of both molecules occurs in early pregnancy, as it does in the rat. However, unlike rats, there is strong basal localisation of talin and paxillin just before implantation in S. crassicaudata, indicating that focal adhesions do not disassemble during pregnancy in this species, and that molecular reinforcement of the epithelium may be a maternal strategy to regulate invasion. Additionally, talin and paxillin do not co‐localise at all stages of pregnancy as they do in the rat. Different localisation patterns among mammalian species demonstrate that not all early pregnancy changes are ubiquitous in mammalian pregnancy, as changes to the basal plasma membrane of the epithelium, in particular, may instead be dependent on mode of implantation. Anat Rec, 300:1150–1159, 2017. © 2016 Wiley Periodicals, Inc.
Baugruben: Ermittlung des Bettungsmoduls auf der Grundlage von Mobilisierungsfunktionen
Authors: Hettler Achim , Hegert Harriet 
Published: December 2016

AbstractBrand et al. [1–3] stellen in umfangreichen Untersuchungen große Abweichungen zwischen gemessenen und nach EB 102 auf der Grundlage von Mobilisierungsfunktionen ermittelten Verformungen fest. Aufgrund der unklaren Sachlage wurde der betreffende Absatz der 4. Auflage in der 5. Auflage der EAB gestrichen. Hegert nimmt in [4] diese Fragestellung auf. Im Folgenden wird über die Ergebnisse berichtet. Es wird gezeigt, dass systematische Fehler bei den unter idealisierten Bedingungen abgeleiteten Mobilisierungsfunktionen oder beim Ansatz des Ausgangsspannungszustands nach Weißenbach und Gollub [5] bzw. EAB [6] ausgeschlossen werden können.Eine erhebliche Verbesserung der Prognose des Bettungsverhaltens lässt sich durch Ansatz eines wirklichkeitsnahen Reibungswinkels im Sinne eines Mittelwerts anstelle eines unteren charakteristischen Werts erreichen. Verwendet man den Vorschlag von Besler [7], lässt sich die Steifigkeit durch Einführung eines Korrekturfaktors unter Beibehaltung der in der Praxis üblichen abgeminderten Reibungswinkel erhöhen, und es sind nicht getrennte Nachweise für den Grenzzustand der Tragfähigkeit und der Gebrauchstauglichkeit erforderlich.
Aggregation kinetics of human mesenchymal stem cells under wave motion
Authors: Tsai Ang‐Chen , Liu Yijun , Yuan Xuegang , Chella Ravindran , Ma Teng 
Published: December 2016

AbstractHuman mesenchymal stem cells (hMSCs) are primary candidates in cell therapy and regenerative medicine but preserving their therapeutic potency following culture expansion is a significant challenge. hMSCs can spontaneously assemble into three‐dimensional (3D) aggregates that enhance their regenerative properties. The present study investigated the impact of hydrodynamics conditions on hMSC aggregation kinetics under controlled rocking motion. While various laboratory methods have been developed for hMSC aggregate production, the rocking platform provides gentle mixing and can be scaled up using large bags as in wave motion bioreactors. The results show that the hMSC aggregation is mediated by cell adhesion molecules and that aggregate size distribution is influenced by seeding density, culture time, and hydrodynamic conditions. The analysis of fluid shear stress by COMSOL indicated that aggregate size distribution is inversely correlated with shear stress and that the rocking angle had a more pronounced effect on aggregate size distribution than the rocking speed due to its impact on shear stress. hMSC aggregates obtained from the bioreactor exhibit increased stemness, migratory properties, and expression of angiogenic factors. The results demonstrate the potential of the rocking platform to produce hMSC aggregates with controlled size distribution for therapeutic application.
Chemical Traits of Hemiparasitism in Odontites luteus
Authors: Venditti Alessandro , Frezza Claudio , Foddai Sebastiano , Serafini Mauro , Nicoletti Marcello , Bianco Armandodoriano 
Published: December 2016

The study of the monoterpene glycosides content of Odontites luteus has shown the presence of a total of fifteen iridoid glucosides. The presence of compounds 1 – 5 and 7 – 10 is perfectly on‐line with both the biogenetic pathway for iridoids biosynthesis in Lamiales and the current botanical classification of the species. On the other side, the presence of compounds like agnuside (6), adoxosidic acid (11), monotropein (12), 6,7‐dihydromonotropein (13), methyl oleoside (14) and methyl glucooleoside (15) is of high interest because, first of all, they have never been reported before in Lamiales. In second instance, the majority of the last compounds are formally derived from a different biogenetic pathway which involves deoxyloganic acid/loganin and led to the formation of decarboxylated iridoid showing the 8β‐configuration. Furthermore, a second abnormality was found during our study and this regards compounds 14 and 15 which are seco‐iriodids and thus not typical for this family. The presence of these unusual compounds, biogenetically not related to species belonging to Lamiales, is a clear evidence of the metabolites transfer from the hosts. In fact, the collection area is also populated by species belonging to Oleaceae and Ericaceae which could be the possible hosts since the biosynthesis of seco‐iridoids and or iridoids related to deoxyloganic acid/loganin pathway, with the 8β‐configuration, is well documented in these species.
Guerbet Reaction over Strontium‐Substituted Hydroxyapatite Catalysts Prepared at Various (Ca+Sr)/P Ratios
Authors: Silvester Lishil , Lamonier Jean‐François , Lamonier Carole , Capron Mickaël , Vannier Rose‐Noëlle , Mamede Anne‐Sophie , Dumeignil Franck 
Published: December 2016

AbstractThe Guerbet reaction of ethanol to heavier products was performed over a series of extensively characterized Sr‐substituted hydroxyapatites (HAPs) with different (Ca+Sr)/P ratios, and thus different structural, textural, and acid–base properties. The acid–base properties were correlated with the reactivity of the solids and an optimal ratio between the amount of acid and basic sites was determined (ca. 4), whereas the ethanol conversion was mainly depending on the specific surface area of the solids. The stoichiometric 100 mol % Sr‐substituted sample (SrAp‐100) was especially efficient in higher alcohols production, which can be illustrated by a total alcohol selectivity (76.4 %) higher than that of all the other solids at a 13 % ethanol isoconversion.
On‐Surface Dual‐Response Structural Transformations of Guanine Molecules and Fe Atoms
Authors: Zhang Chi , Wang Likun , Xie Lei , Ding Yuanqi , Xu Wei 
Published: December 2016

AbstractStructural transformation of metal–organic nanostructures holds great promise for structural diversity and flexibility and opens the way towards an adaptive and evolutive chemistry owing to the dynamic characteristic of coordination bonds. It is thus generally interesting and also challenging to develop systems showing reversible structural transformations which involve multiple metal–organic motifs on surfaces. Here, we have successfully constructed a system that presents structural transformations on a solid surface, in which controllable formation of multiple metal–organic nanostructures (with different coordination binding modes by use of distinct binding sites) in response to both metal atoms and molecules is achieved at room temperature (RT) under ultrahigh vacuum (UHV) conditions. The key to making these interconversions successful is the intrinsic dynamic characteristic of coordination bonds together with the coordination priority and diversity.
Computational Investigation of the Role Played by Rhodium(V) in the Rhodium(III)‐Catalyzed ortho‐Bromination of Arenes
Authors: Zhang Tao , Qi Xiaotian , Liu Song , Bai Ruopeng , Liu Chao , Lan Yu 
Published: December 2016

AbstractIn this study, M11‐L was used to evaluate the feasibility of the formation of rhodium(V) species using the rhodium(III)‐catalyzed ortho‐bromination of arenes as a model reaction. In most cases for these types of reactions, DFT calculations reveal that the bromination step involves a Br transfer from N‐bromosuccinimide to the reacting arylrhodium to form a bromonium intermediate, followed by a Br shift to generate a new C−Br bond, which is more favorable than the previously proposed RhIII/RhV catalytic cycle. The rhodium catalyst remains in its +3 oxidation state throughout. The substituent effects of the reacting arene were studied, and computational results showed that the introduction of electron‐donating groups on the reacting arene was favorable for this pathway. In contrast, the inclusion of a strong electron‐withdrawing group on the aromatic ring would hinder the formation of a bromonium intermediate. Therefore, the RhIII/RhV catalytic cycle is favorable in cases that involve a RhV intermediate, which is generated by oxidative addition with NBS. In this pathway, the C−Br bond is formed by reductive elimination from the RhV intermediate. Additionally, a distortion–interaction analysis model along the reaction pathway was used to explain the directing‐group effects. The results showed that the interaction energy controlled the reactivity because of the difference in electronic nature of various directing groups.
Traceable Size and Size Distribution Calibrations of Nanoparticles
Authors: Buhr Egbert , Dziomba Thorsten , Frase Carl Georg , Krumrey Michael , Bosse Harald 
Published: December 2016

AbstractQuality control of nanoparticle production processes requires traceable calibration methods for size and size distribution which are presented and discussed in this article. The main focus is on the one hand the application of small‐angle X‐ray scattering for an integral measurement of nanoparticles in liquid suspension and on the other hand scanning electron microscopy in transmission for a microscopic measurement method of nanoparticles prepared on a substrate. In addition, characterization by scanning probe microscopy is covered.
Synthesis and Properties of a Novel 3D Europium Coordination Polymer with Helical Chain and (3,6)‐Connected rtl Net
Authors: Liu Zhifeng , Lai Bowen , Wen Huiliang , Robbins Julianne , Huang Nei 
Published: December 2016

AbstractThe first coordination polymer of 2,2′‐((4‐carboxymethyl‐1,3‐phenylene)bis(oxy)) diacetic acid (H3L) with europium(III) ion, [Eu(L)(H2O)]·3H2O (1), has been hydrothermally synthesized and structurally characterized. Complex 1 exhibits a 3D coordination polymer with helical chain and rtl topology of the point symbol (4·62)2(42·610·83) based on [Eu2(COO)4] as secondary building unit (SBU). Furthermore, the luminescent and magnetic properties of complex 1 are studied.
A Highly Selective and Sensitive Fluorescent Probe Recognition for Co2+ in Aqueous Media Based on 8‐Hydroxyquinolin‐2‐carbaldehyde‐2‐pyridylformylhydrazone Derivative
Authors: Zhong Keli , Zhao Jie , Zhou Xue , Hou Shuhua , Bian Yanjiang , Li Jianrong , Tang Lijun 
Published: December 2016

AbstractA new (8‐hydroxyquinolin‐2‐yl)methylene picolinohydrazide derivative (L) has been successfully synthesized and characterized. The probe L displays high selectivity to Co2+ in CH3CN/HEPES (1:1, Ｖ/Ｖ, 10 mmol·L−1, pH=7.4) with a fluorescence "ON‐OFF" response. The Co2+ ion recognition event possesses some distinct features including rapid response, high selectivity and sensitivity, good anti‐interference ability and being applicable within a wide pH range. Based on job's plot and ESI‐MS studies, the 1:1 binding mode was proposed. The binding constant of L and Co2+ is 1.63×108 L·mol−1 and the detection limit is 1.15 µmol·L−1. Natural water samples experiments revealed that probe L can be potentially applied to the detection of Co2+ in real environment.
Comparative Studies of Non‐noble Metal Modified Mesoporous M‐Ni‐CaO‐ZrO2 (M = Fe, Co, Cu) Catalysts for Simulated Biogas Dry Reforming
Authors: Wang Changzhen , Zhang Yin , Wang Yongzhao , Zhao Yongxiang 
Published: December 2016

AbstractThe present work is aimed to improve the performance of Ni‐based catalysts for biogas dry reforming by adding a second non‐noble metal (Fe, Co, Cu) into a previously studied mesoporous Ni‐CaO‐ZrO2 nanocomposite. Biogas was simulated with equivalent methane and carbon dioxide for the dry reforming reaction. X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), N2 adsorption, temperature‐programmed reduction (TPR), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) measurements were taken to characterize the structural and textual properties of the bimetallic catalysts as well as the accumulated carbon deposition. The addition of Fe leads to a less ordering growth of mesopores of Fe‐Ni‐CaO‐ZrO2 sample, and the existence of Cu results in a relatively larger portion of free NiO in Cu‐Ni‐CaO‐ZrO2. Compared with Fe and Cu, the presence of Co could efficiently form a beneficial dual metal effect and enhance the strong metal support interaction between Ni and CaO‐ZrO2, thus enhancing the activity and stability of the catalyst in biogas dry reforming reaction.
Synthetic Analogues of Betulinic Acid as Potent Inhibitors of PS1/BACE1 Interaction to Reduce Aβ Generation
Authors: Zhang Chenlu , Wang Xiaoyin , Cui Jin , Li Xiaohang , Zhang Yangming , Wang Xin , Gu Haifeng , Li Wei , Xie Xin , Zhao Jian , Pei Gang , Nan Fajun 
Published: December 2016

AbstractThe lupane‐type triterpenoids are endowed with a wide range of biological activities such as antiviral, anti‐inflammatory and anticancer activity. We describe here its potential application in Alzheimer's disease (AD) treatment as an inhibitor of PS1/BACE1 interaction. 3‐α‐Akebonoic acid, which emanated from a high throughput screening (HTS), was discovered to interfere with PS1/BACE1 interaction and reduce amyloid β‐protein (Aβ) production. In view of the limited source, we instead used naturally rich betulinic acid (compound 2) as starting material for lead optimization and a focused library of its derivatives was constructed to gain a better understanding of the structure activity relationship (SAR) of triterpenoid‐type inhibitor of PS1/BACE1 interaction. Compound 22 was finally chosen as the most potent PS1/BACE1 interaction inhibitor, which reduced Aβ generation effectively.
Timing isn't everything: Influenza vaccination in cancer patients
Authors: Dulek Daniel E. , Halasa Natasha B. 
Published: December 2016

Influenza vaccination is a critical intervention for improving the health of cancer patients with yearly influenza immunization recommended by the CDC. Influenza vaccine studies in cancer patients generally demonstrate impaired influenza vaccine responses in comparison with age‐matched, healthy controls. The present study by Keam et al. defined the effect of vaccine timing with respect to cytotoxic chemotherapy regimens on immunogenicity and adverse events after influenza vaccination in cancer patients with solid malignancies. No significant differences in post‐vaccination serologic response or adverse event frequencies were found between patients vaccinated concurrent with cytotoxic chemotherapy administration and patients vaccinated during the cytopenic period post‐chemotherapy administration. Further study is warranted to better define optimal timing and interventions to improve influenza vaccine immunogenicity in this at‐risk population.See also pages 841‐8.
Inflammation of peripheral tissues and injury to peripheral nerves induce differing effects in the expression of the calcium‐sensitive N‐arachydonoylethanolamine‐synthesizing enzyme and related molecules in rat primary sensory neurons
Authors: Sousa‐Valente João , Varga Angelika , Torres‐Perez Jose Vicente , Jenes Agnes , Wahba John , Mackie Ken , Cravatt Benjamin , Ueda Natsuo , Tsuboi Kazuhito , Santha Peter , Jancso Gabor , Tailor Hiren , Avelino António , Nagy Istvan 
Published: December 2016

AbstractElevation of intracellular Ca2+ concentration induces the synthesis of N‐arachydonoylethanolamine (anandamide) in a subpopulation of primary sensory neurons. N‐acylphosphatidylethanolamine phospholipase D (NAPE‐PLD) is the only known enzyme that synthesizes anandamide in a Ca2+‐dependent manner. NAPE‐PLD mRNA as well as anandamide's main targets, the excitatory transient receptor potential vanilloid type 1 ion channel (TRPV1), the inhibitory cannabinoid type 1 (CB1) receptor, and the main anandamide‐hydrolyzing enzyme fatty acid amide hydrolase (FAAH), are all expressed by subpopulations of nociceptive primary sensory neurons. Thus, NAPE‐PLD, TRPV1, the CB1 receptor, and FAAH could form an autocrine signaling system that could shape the activity of a major subpopulation of nociceptive primary sensory neurons, contributing to the development of pain. Although the expression patterns of TRPV1, the CB1 receptor, and FAAH have been comprehensively elucidated, little is known about NAPE‐PLD expression in primary sensory neurons under physiological and pathological conditions. This study shows that NAPE‐PLD is expressed by about one‐third of primary sensory neurons, the overwhelming majority of which also express nociceptive markers as well as the CB1 receptor, TRPV1, and FAAH. Inflammation of peripheral tissues and injury to peripheral nerves induce differing but concerted changes in the expression pattern of NAPE‐PLD, the CB1 receptor, TRPV1, and FAAH. Together these data indicate the existence of the anatomical basis for an autocrine signaling system in a major proportion of nociceptive primary sensory neurons and that alterations in that autocrine signaling by peripheral pathologies could contribute to the development of both inflammatory and neuropathic pain.
Stability of Odd‐ Versus Even‐Electron Gas‐Phase (Quasi)Molecular Ions Derived from Pyridine‐Substituted N‐Heterotriangulenes
Authors: Hitzenberger Jakob F. , Dral Pavlo O. , Meinhardt Ute , Clark Timothy , Thiel Walter , Kivala Milan , Drewello Thomas 
Published: December 2016

AbstractInvited for this month's cover are the collaborating groups at the Friedrich‐Alexander University Erlangen‐Nürnberg (FAU), Germany and at the Max‐Planck‐Institut für Kohlenforschung, Germany. The cover picture shows the symbiosis of quantum chemical theory and gas‐phase collision experiment investigating the influence of the electronic state on stability of the radical cation ([M]+.) and protonated triangulene ([M+H]+). The dissociation of the radical cation requires less energy due to the formation of an energetically favored extended aromatic π‐system. Read the full text of the article at 10.1002/cplu.201600416.
Community structure affects trophic ontogeny in a predatory fish
Authors: Sánchez‐Hernández Javier , Eloranta Antti P. , Finstad Anders G. , Amundsen Per‐Arne 
Published: December 2016

AbstractWhile most studies have focused on the timing and nature of ontogenetic niche shifts, information is scarce about the effects of community structure on trophic ontogeny of top predators. We investigated how community structure affects ontogenetic niche shifts (i.e., relationships between body length, trophic position, and individual dietary specialization) of a predatory fish, brown trout (Salmo trutta). We used stable isotope and stomach content analyses to test how functional characteristics of lake fish community compositions (competition and prey availability) modulate niche shifts in terms of (i) piscivorous behavior, (ii) trophic position, and (iii) individual dietary specialization. Northern Scandinavian freshwater fish communities were used as a study system, including nine subarctic lakes with contrasting fish community configurations: (i) trout‐only systems, (ii) two‐species systems (brown trout and Arctic charr [Salvelinus alpinus] coexisting), and (iii) three‐species systems (brown trout, Arctic charr, and three‐spined sticklebacks [Gasterosteus aculeatus] coexisting). We expected that the presence of profitable small prey (stickleback) and mixed competitor–prey fish species (charr) supports early piscivory and high individual dietary specialization among trout in multispecies communities, whereas minor ontogenetic shifts were expected in trout‐only systems. From logistic regression models, the presence of a suitable prey fish species (stickleback) emerged as the principal variable determining the size at ontogenetic niche shifts. Generalized additive mixed models indicated that fish community structure shaped ontogenetic niche shifts in trout, with the strongest positive relationships between body length, trophic position, and individual dietary specialization being observed in three‐species communities. Our findings revealed that the presence of a small‐sized prey fish species (stickleback) rather than a mixed competitor–prey fish species (charr) was an important factor affecting the ontogenetic niche‐shift processes of trout. The study demonstrates that community structure may modulate the ontogenetic diet trajectories of and individual niche specialization within a top predator.