bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Air‐stable 1T Phase of Molybdenum Disulfide for Efficient Electrocatalytic Hydrogen Evolution
Authors: Jia Wei , Zhou Xu , Huang Yudai , Cao Yali , Sun Ying , Jia Dianzeng 
Published: November 2018

AbstractPhase engineering of MoS2 from the thermodynamically stable 2H phase to the metastable 1T phase has been demonstrated as an effective way to enhance the electrocatalytic activity for hydrogen evolution reaction (HER). However, the development of highly stable and efficient 1T‐MoS2‐based electrocatalysts toward HER still remains a great challenge. Herein, a facile hydrothermal strategy was introduced for the preparation of stable 1T‐MoS2 via a reduced graphene oxide (RGO)‐assisted process. The optimal catalyst of MoS2/RGO can keep highly stable in air over 90 days without significant activity fading due to Mo−O interactions, which effectively prevent the transformation of 1T phase back to 2H. The catalyst affords superior HER catalytic activity with a low overpotential of 213 mV versus reversible hydrogen electrode (RHE) at a current density of −10 mA cm−2, a small Tafel slope of 43 mV dec−1, a high exchange current density of 0.83 mA cm−2, and excellent durability, which outperforms its corresponding 2H counterpart. The enhanced electrocatalytic activity of the optimal MoS2/RGO sample is associated with the RGO, which can not only facilitate charge transfer along MoS2 nanosheets but also stabilize the 1T‐MoS2 with a high exposure of active sites for HER. This work paves a new pathway for designing highly efficient MoS2‐based electrocatalysts through phase engineering.
Heteromultivalent Glycooligomers as Mimetics of Blood Group Antigens
Authors: Bücher Katharina S. , Konietzny Patrick B. , Snyder Nicole L. , Hartmann Laura 
Published: November 2018

AbstractPrecision glycomacromolecules have proven to be important tools for the investigation of multivalent carbohydrate–lectin interactions by presenting multiple glycan epitopes on a highly‐defined synthetic scaffold. Herein, we present a new strategy for the versatile assembly of heteromultivalent glycomacromolecules that contain different carbohydrate motifs in proximity within the side chains. A new building block suitable for the solid‐phase polymer synthesis of precision glycomacromolecules was developed with a branching point in the side chain that bears a free alkyne and a TIPS‐protected alkyne moiety, which enables the subsequent attachment of different carbohydrate motifs by on‐resin copper‐mediated azide–alkyne cycloaddition reactions. Applying this synthetic strategy, heteromultivalent glycooligomers presenting fragments of histo‐blood group antigens and human milk oligosaccharides were synthesized and tested for their binding behavior towards bacterial lectin LecB.
Deciphering the Multifarious Charge‐Transport Behaviour of Crystalline Propeller‐Shaped Triphenylamine Analogues
Authors: Ambili R. V. , Sasikumar Devika , Hridya P. , Hariharan Mahesh 
Published: November 2018

AbstractA collection of para‐substituted propeller‐shaped triphenylamine (TPA) derivatives have been computationally investigated for charge‐transport characteristics exhibited by the derivatives by using the Marcus–Hush formalism. The various substituents chosen herein, with features that range from electron withdrawing to electron donating in nature, play a key role in defining the reorganisation energy and electronic coupling properties of the TPA derivatives. The TPA moiety is expected to possess weak electronic coupling on the basis of poor orbital overlap upon aggregation, owing to the restriction imposed by the propeller shape of the TPA core. However, the substituent groups attached to the TPA core can significantly dictate the crystal‐packing motif of the TPA derivatives, wherein the variety of noncovalent intermolecular interactions subsequently generated drive the packing arrangement and influence electronic coupling between the neighbouring orbitals. Intermolecular interactions in the crystalline architecture of TPA derivatives were probed by using Hirshfeld and quantum theory of atoms‐in‐molecules techniques. Furthermore, symmetry‐adapted perturbation theory analysis of the TPA analogues has revealed that a periodic arrangement of energetically stable dimers with significant electronic coupling is essential to contribute high charge‐carrier mobility to the overall crystal.
Complexation and Versatile Reactivity of a Highly Lewis Acidic Cationic Mg Complex with Alkynes and Phosphines
Authors: Pahl Jürgen , Stennett Tom E. , Volland Michel , Guldi Dirk M. , Harder Sjoerd 
Published: November 2018

Abstract[(BDI)Mg+][B(C6F5)4−] (1; BDI=CH[C(CH3)NDipp]2; Dipp=2,6‐diisopropylphenyl) was prepared by reaction of (BDI)MgnPr with [Ph3C+][B(C6F5)4−]. Addition of 3‐hexyne gave [(BDI)Mg+⋅(EtC≡CEt)][B(C6F5)4−]. Single‐crystal X‐ray analysis, NMR investigations, Raman spectra, and DFT calculations indicate a significant Mg‐alkyne interaction. Addition of the terminal alkynes PhC≡CH or Me3SiC≡CH led to alkyne deprotonation by the BDI ligand to give [(BDI‐H)Mg+(C≡CPh)]2⋅2 [B(C6F5)4−] (2, 70 %) and [(BDI‐H)Mg+(C≡CSiMe3)]2⋅2 [B(C6F5)4−] (3, 63 %). Addition of internal alkynes PhC≡CPh or PhC≡CMe led to [4+2] cycloadditions with the BDI ligand to give {Mg+C(Ph)=C(Ph)C[C(Me)=NDipp]2}2⋅ 2 [B(C6F5)4−] (4, 53 %) and {Mg+C(Ph)=C(Me)C[C(Me)=NDipp]2}2⋅2 [B(C6F5)4−] (5, 73 %), in which the Mg center is N,N,C‐chelated. The (BDI)Mg+ cation can be viewed as an intramolecular frustrated Lewis pair (FLP) with a Lewis acidic site (Mg) and a Lewis (or Brønsted) basic site (BDI). Reaction of [(BDI)Mg+][B(C6F5)4−] (1) with a range of phosphines varying in bulk and donor strength generated [(BDI)Mg+⋅PPh3][B(C6F5)4−] (6), [(BDI)Mg+⋅PCy3][B(C6F5)4−] (7), and [(BDI)Mg+⋅ PtBu3][B(C6F5)4−] (8). The bulkier phosphine PMes3 (Mes=mesityl) did not show any interaction. Combinations of [(BDI)Mg+][B(C6F5)4−] and phosphines did not result in addition to the triple bond in 3‐hexyne, but during the screening process it was discovered that the cationic magnesium complex catalyzes the hydrophosphination of PhC≡CH with HPPh2, for which an FLP‐type mechanism is tentatively proposed.
NMR chiral discrimination of chalcogen containing secondary alcohols
Authors: Marques Naiade B.G. , Jacob Raquel G. , Perin Gelson , Lenardão Eder J. , Alves Diego , Silva Márcio S. 
Published: November 2018

AbstractHere, we report the general strategies by which NMR spectroscopy can be used to determine the enantiopurity and absolute configuration of chalcogen containing secondary alcohols, including the evaluation of the use of chiral solvating and chiral derivatizing agents. The BINOL/DMAP ternary complex demonstrated a simple and fast protocol for determining enantiopurity. The drug Naproxen afforded a stable, nonhygroscopic, and readily available chiral derivatizing agent (CDA) for NMR chiral discrimination of chalcogen containing secondary alcohols. The chiral recognition by CDA and chiral solvating agent (CSA) was assessed using 1H, 77Se‐{1H}, and 125Te‐{1H} NMR spectroscopy. A simple model for the assignment of the absolute configuration from NMR data is presented.
Impact of co‐flow on the spray flame behaviour applied to nanoparticle synthesis
Authors: Buss Lizoel , Meierhofer Florian , Bianchi Neto Pedro , França Meier Henry , Fritsching Udo , Noriler Dirceu 
Published: November 2018

AbstractFlame spray pyrolysis (FSP) is an established process to synthesize nanoparticles of various metals and metal oxides. Applying open or enclosed configurations of the FSP reactor is an efficient tool to control the fuel‐oxidizer ratio in the reaction zone and, thus, the temperature distribution and the particle formation and growth process. In the present work, geometrical setups representing an open and an enclosed flame reactor are compared and their influence on the temperature, velocity, and particle characteristics is investigated. In addition, several distinct kinetic mechanisms for the combustion reactions are evaluated and their effects on the local reactor temperature and gas composition distribution are analyzed. An Eulerian‐Lagrangian approach is adopted to describe the multiphase turbulent gas‐droplet flow and a monodisperse approach based on the population balance equation (PBE) model is implemented to predict the particle formation and evolution. From the open reactor results, the air entrainment mass flow rate of gas into the flame is calculated. Several numerical experiments are performed with the enclosed setup. Supplying an appropriate co‐flow rate into the enclosed reactor results in similar flame behaviour as found for the open reactor configuration. By reducing the co‐flow gas, strong recirculation zones and particle deposition on the enclosure walls are observed. In this situation, the local temperature increases considerably, resulting in larger primary nanoparticle diameters.
Design and characterization of a multi‐layered polymeric drug delivery vehicle
Authors: Tan Kei Xian , Ujan Safina , Danquah Michael K. , Lau Sie Yon 
Published: November 2018

AbstractAptamer‐mediated targeted delivery is a promising advanced therapeutic delivery strategy with the potential to provide site‐directed cyto‐toxicity to malignant cells. However, effective translation of preclinical aptamer‐navigated targeted delivery data into clinical success has been challenged by several biophysical and biochemical factors including rapid renal clearance, endonuclease‐induced degradation, and cell membrane electrostatic repulsion. Aptamer‐conjugated biopolymer systems represent new and smart drug carriers capable of delivering adequate amounts of drug molecules sufficient to elicit effective in vivo therapies at target sites in a controlled and sustained drug release pattern. In this work, a novel co‐polymeric multi‐layer BSA‐loaded thrombin aptamer‐conjugated PLGA‐PEI (DPAP) formulation was synthesized using a w/o/w double emulsion and characterized layer‐by‐layer in vivo. DLS analysis of the DPAP particles showed a positively charged DPAP particulate system with a D[4,3] average hydrodynamic size of ∼0.866 μm and a zeta potential of +9.85 mV. The zeta potential and D[4,3] average hydrodynamic size of DPAP layered compartments demonstrated pH‐dependence but are not temperature dependent. The ionic strength of the binding medium affected the degradation and release rates of DPAP micro‐particles. A strong binding strength and shielding effect of DPAP towards encapsulated BSA molecules was observed under increasing ionic strength. Thermogravimetric analysis showed that the DPAP formulation decomposes at ∼300 °C, demonstrating the thermal stability of the polymer composite for effective storage in temperate environments. The data from this study is vital to engineer the interactions between DPAP polymeric system and cellular structures in order to enhance targeting events. While the DPAP construct demonstrates a great potential for targeted delivery, more in vivo delivery work is essential to prove its pre‐clinical targeting capability.
Understanding the Influence of Rheological Properties of Shear‐Thinning Liquids on Segmented Flow in Microchannel using CLSVOF Based CFD Model
Authors: Sontti Somasekhara Goud , Pallewar Pankaj G. , Ghosh Amritendu Bhuson , Atta Arnab 
Published: November 2018

AbstractIn this study, two phase gas‐shear‐thinning liquid flow in a square microchannel is numerically investigated using the coupled level set and volume of fluid (CLSVOF) methods. A systematic investigation is carried out to explore the influence of polyacrylamide (PAM) concentration, surface tension, velocity ratios, and contact angle on the gas slug length, volume, unit cell length, and pressure drop. Three different concentrations of PAM solutions, which exhibit shear‐thinning behaviour are considered as the continuous phase. Gas slug length, volume, and unit cell length decreased with increasing the PAM concentration. Velocity and non‐homogeneous viscosity distributions in the liquid slug for three different PAM concentration solutions are reported. Gas slug length decreases with an increase of the contact angle and the bubble shape change from convex to concave. This numerical work provides the fundamental insights in segmented flow formation and two‐phase flow characteristics comprising shear‐thinning liquids.
A Three‐Dimensional MnII‐[MoIII(CN)7]4– Ferrimagnet Containing Formate as a Second Bridging Ligand
Authors: Shi Le , Shao Dong , Shen Fu‐Ying , Wei Xiao‐Qin , Wang Xin‐Yi 
Published: November 2018

Summary of main observation and conclusionSelf‐assembly of the [Mo(CN)7]4– anion and the Mn2+ ion in the aqueous solution containing ammonium formate results in a new coordination polymer, {(NH4)3[(H2O)Mn3(HCOO)][Mo(CN)7]2·4H2O}n. Single crystal X‐ray analysis revealed a very complicated three‐dimensional (3D) framework, where both the [Mo(CN)7]4– and the formate anions act as bridges between the MnII centers. Magnetic measurements revealed that this compound displays ferrimagnetic ordering below 70 K. Competing antiferromagnetic interactions between the spin carriers might lead to spin frustration and non‐linear alignment of the magnetic moments. Specifically, this compound is the first mixed [Mo(CN)7]4–/HCOO– bridged molecule magnet.
Highly Stable and Antibacterial Two‐Dimensional Tungsten Disulfide Lamellar Membrane for Water Filtration
Authors: Cheng Peng , Chen Yan , Yan Xi , Wang Yanjie , Lang Wan‐Zhong 
Published: November 2018

AbstractTwo‐dimensional (2D) lamellar membranes consisting of restacked WS2 nanosheets have shown excellent separation properties for water filtration. The stability, antifouling properties, and antibacterial activities of the WS2 laminar membranes were investigated for practical application. We discovered that the separation properties of the WS2 laminar membranes changed slightly after soaking in water for 28 days as well as that of a 45 h‐cross‐flow filtration, demonstrating an extraordinary operational stability of the WS2 laminar membranes. The remarkable stability is related to the dominant van der Waals interactions between WS2 nanosheets. In addition, the WS2 laminar membranes exhibited excellent antibacterial properties against S. aureus and E. coli with antibacterial rates of 91.3 % and 89.7 %, respectively. These properties of the WS2 laminar membranes make them promising candidates for application in water filtration.
Psychomotor Dysfunction in Rett Syndrome: Insights into the Neurochemical and Circuit Roots
Authors: Liao Wenlin 
Published: November 2018

AbstractRett syndrome (RTT) is a monogenic neurodevelopmental disorder caused by mutations in the methyl‐CpG binding protein 2 (MECP2) gene. Patients with RTT develop symptoms after 6–18 months of age, exhibiting characteristic movement deficits, such as ambulatory difficulties and loss of hand skills, in addition to breathing abnormalities and intellectual disability. Given the striking psychomotor dysfunction, numerous studies have investigated the underlying neurochemical and circuit mechanisms from different aspects. Here, I review the evidence linking MeCP2 deficiency to alterations in neurotransmission and neural circuits that govern the psychomotor function and discuss a recently identified pathological origin underlying the psychomotor deficits in RTT.
Extinctions of interactions: quantifying a dung beetle–mammal network
Authors: Raine Elizabeth H. , Mikich Sandra B. , Lewis Owen T. , Riordan Philip , Vaz‐de‐Mello Fernando Z. , Slade Eleanor M. 
Published: November 2018

AbstractLoss of large‐bodied mammals across the globe through hunting, habitat degradation, and fragmentation is one of the most significant anthropogenic impacts on the environment. Cascading effects of these extinctions through ecosystems have been little studied, although correlative studies have revealed co‐extinctions in closely linked groups, with implications for ecosystem structure and function. Despite playing important roles in seed dispersal and hence seedling recruitment, mammals have been largely neglected in network studies. Similarly, the role of secondary seed dispersers, such as ants and dung beetles, has been largely unexplored. Most dung beetles rely on mammal feces for feeding and breeding and provide a suite of important ecosystem functions and services. While dung beetle community responses to environmental change have been widely investigated, studies quantifying the network of associations between dung beetle and mammal species are lacking. By developing the first quantitative mammal–dung beetle networks, we address several important knowledge gaps contributing to the understanding of how interactions in networks involving mammals and secondary insect seed dispersers are structured. We use the resulting quantitative interaction networks to model mammal species extinction scenarios to further explore the consequences for dung beetle populations, and the extent to which networks change the strength of interactions through resource switching. Dung beetle feeding and breeding networks did not differ significantly in structure and showed high nestedness and low levels of trophic specialization. Simulations suggested that mammal extinction scenarios based on mammal body mass and mammal dung volume will impact dung beetle populations to a greater extent than random scenarios of mammal loss. Thus, despite their generalist feeding preferences, realistic mammal extinction scenarios have the potential to negatively impact the dung beetle community, which may have consequences for ecosystem functioning.
Fine‐scale environmental DNA sampling reveals climate‐mediated interactions between native and invasive trout species
Authors: Wilcox Taylor M. , Young Michael K. , McKelvey Kevin S. , Isaak Daniel J. , Horan Dona L. , Schwartz Michael K. 
Published: November 2018

AbstractIt is widely recognized that biotic interactions may act as important mediators of species responses to climate change. However, collecting the abiotic and biotic covariates at the resolution and extent needed to reveal these interactions from species distribution models is often prohibitively expensive and labor‐intensive. Here we used crowd‐sourced environmental DNA sampling—the inference of species presence from genetic material in the environment—and high‐resolution habitat covariates across 630 sites over an area of nearly 10,000 km2 to build an accurate species distribution model (AUC = 0.96; prediction accuracy = 0.90) for bull trout in cold‐water habitats that incorporates fine‐scale, context‐dependent interactions with invasive brook trout. We then used this model to project possible climate change and brook trout invasion scenarios for bull trout forward in time. Our environmental DNA sampling results were concordant with traditional electrofishing samples in the basin and revealed species patterns that were consistent with previous studies: Bull trout were positively associated with larger stream sizes and negatively associated with high brook trout abundances. However, our modeling also revealed an important nuance: At high abundance, brook trout appear to exclude bull trout from small streams, even those below the thermal optima for brook trout. Climate projections suggest a loss of suitable bull trout habitat as streams warm and summer flows decrease, which could make deleterious interactions with brook trout more common in the future. Where brook trout are invading bull trout habitats, streams that are both large and cold are most likely to provide native bull trout with long‐term refuges.
Eomesodermin controls a unique differentiation program in human IL‐10 and IFN‐γ coproducing regulatory T cells
Authors: Gruarin Paola , Maglie Stefano , De Simone Marco , Häringer Barbara , Vasco Chiara , Ranzani Valeria , Bosotti Roberto , Noddings Johanna S. , Larghi Paola , Facciotti Federica , Sarnicola Maria L. , Martinovic Martina , Crosti Mariacristina , Moro Monica , Rossi Riccardo L. , Bernardo Maria E. , Caprioli Flavio , Locatelli Franco , Rossetti Grazisa , Abrignani Sergio , Pagani Massimiliano , Geginat Jens 
Published: November 2018

AbstractWhether human IL‐10‐producing regulatory T cells (“Tr1”) represent a distinct differentiation lineage or an unstable activation stage remains a key unsolved issue. Here, we report that Eomesodermin (Eomes) acted as a lineage‐defining transcription factor in human IFN‐γ/IL‐10 coproducing Tr1‐like cells. In vivo occurring Tr1‐like cells expressed Eomes, and were clearly distinct from all other CD4+ T‐cell subsets, including conventional cytotoxic CD4+ T cells. They expressed Granzyme (Gzm) K, but had lost CD40L and IL‐7R expression. Eomes antagonized the Th17 fate, and directly controlled IFN‐γ and GzmK expression. However, Eomes binding to the IL‐10 promoter was not detectable in human CD4+ T cells, presumably because critical Tbox binding sites of the mouse were not conserved. A precommitment to a Tr1‐like fate, i.e. concominant induction of Eomes, GzmK, and IFN‐γ, was promoted by IL‐4 and IL‐12‐secreting myeloid dendritic cells. Consistently, Th1 effector memory cells contained precommitted Eomes+GzmK+ T cells. Stimulation with T‐cell receptor (TCR) agonists and IL‐27 promoted the generation of Tr1‐like effector cells by inducing switching from CD40L to IL‐10. Importantly, CD4+Eomes+ T‐cell subsets were present in lymphoid and nonlymphoid tissues, and their frequencies varied systemically in patients with inflammatory bowel disease and graft‐versus‐host disease. We propose that Eomes+ Tr1‐like cells are effector cells of a unique GzmK‐expressing CD4+ T‐cell subset.
Combining geochemistry and petrography to provenance Lionato and Lapis Albanus tuffs used in Roman temples at Sant’Omobono, Rome, Italy
Authors: Diffendale Daniel P. , Marra Fabrizio , Gaeta Mario , Terrenato Nicola 
Published: November 2018

AbstractTufo Lionato is a volcanic tuff that was used extensively for construction in Rome, Italy, during antiquity and after; at least three varieties can be identified: Anio, Monteverde, and Portuense. The widespread introduction of Tufo Lionato in Roman construction is generally dated to the mid‐second century before the common era (B.C.E.). Another tuff, Lapis Albanus, is held to have been introduced during the third century B.C.E. Due to their similar macroscopic appearance, it is impossible to reliably distinguish visually among varieties of Tufo Lionato, or between Lapis Albanus and other “peperino” tuffs, nor does geochemistry alone always allow definitive identifications. A combination of geochemical and petrographical analyses is presented here, to provenance building stone from the Roman temples of Fortuna and Mater Matuta at Sant’Omobono in Rome. The combination of techniques allows for secure identification of Anio tuff and Lapis Albanus, and their use in structures of the fourth–third and fifth–third centuries B.C.E., respectively, one to two centuries earlier than previously demonstrated. These findings show a diversification of tuffs used by the Roman construction industry earlier than henceforth acknowledged, and suggest the ability of archaeometric techniques to bring new perspectives even to such familiar archaeological contexts as the city of Rome.