bluuebunny/crossref_metadata_2025_split huggingface dataset:
Amphiphile Polymer‐Lipidkonjugate zur potenten lymphatischen Anreicherung von TLR7/8‐Agonisten ermöglichen eine örtlich begrenzte Aktivierung des angeborenen Immunsystems
Authors: De Vrieze Jana , Louage Benoit , Deswarte Kim , Zhong Zifu , De Coen Ruben , Van Herck Simon , Nuhn Lutz , Kaas Frich Camilla , Zelikin Alexander N. , Lienenklaus Stefan , Sanders Niek N. , Lambrecht Bart N. , David Sunil A. , De Geest Bruno G. 
Published: August 2019

AbstractDie Induktion unkontrollierter systemischer Entzündungsprozesse blockiert derzeit die unmittelbare klinische Anwendung verschiedener Klassen von nierdermolekularen Immunmodulatoren. Darunter fallen zum Beispiel auch die Imidazochinolin‐basierten TLR7/8‐Agonisten, die eine erfolgversprechende Anwendung beim Impfen oder in der Krebsimmuntherapie finden könnten. Hierbei würden Lipidmotive eine Abhilfe schaffen, da sie sich an Serumproteine anlagern und so zu einer Akkumulation im lymphatischen Gewebe beitragen. Aus diesem Grund haben wir amphiphile Polymer‐Lipidkonjugate als Transporter entwickelt, die die systemischen Entzündungserscheinungen der niedermolekularen Wirkstoffe unterdrücken und stattdessen eine potente Immunaktivierung allein in den Lymphknoten ermöglichen. In dieser Arbeit legen wir erste systematische Struktur‐Wirkstoffbeziehungen für eine optimale lymphatische Anreicherung dar.
Fast and Quantitative NMR Metabolite Analysis Afforded by a Paramagnetic Co‐Solute
Authors: Mulder Frans A. A. , Tenori Leonardo , Luchinat Claudio 
Published: August 2019

AbstractNMR spectroscopy is an indispensable technique for the determination of the chemical identity and structure of small molecules. The method is especially recognized for its robustness and intrinsically quantitative nature, and has manifested itself as a key analytical platform for diverse fields of application, ranging from chemical synthesis to metabolomics. Unfortunately, the slow recovery of nuclear spin polarization by spin‐lattice (T1) relaxation causes most experimental time to be lost on idle waiting. Furthermore, truly quantitative NMR (qNMR) spectroscopy requires waiting times of 5‐times the longest T1 in the sample, making qNMR spectroscopy slow and inefficient. We demonstrate here that co‐solute paramagnetic relaxation can mitigate these two problems simultaneously. The addition of a small amount of paramagnetic gadolinium chelate, available in the form of commercial contrast‐agent solutions, enables cheap, quantitative, and efficient high‐throughput mixture analysis.
Co‐catalyst effects on the thermal stability/activity of N,N,N‐Co ethylene polymerization Catalysts Bearing Fluoro‐Substituted N‐2,6‐dibenzhydrylphenyl groups
Authors: Zhang Qiuyue , Ma Yanping , Suo Hongyi , Solan Gregory A. , Liang Tongling , Sun Wen‐Hua 
Published: August 2019

The unsymmetrical bis (arylimino)pyridines, 2‐[CMeN{2,6‐{(4‐FC6H4)2CH}2–4‐t‐BuC6H2}]‐6‐(CMeNAr)C5H3N (Ar = 2,6‐Me2C6H3 L1, 2,6‐Et2C6H3 L2, 2,6‐i‐Pr2C6H3 L3, 2,4,6‐Me3C6H2 L4, 2,6‐Et2–4‐MeC6H2 L5), each containing one N‐aryl group bedecked with ortho‐substituted fluorobenzhydryl groups, have been employed in the preparation of the corresponding five‐coordinate cobalt (II) chelates, LCoCl2 (Co1 – Co5); the symmetrical comparator [2,6‐{CMeN(2,6‐(4‐FC6H4)2CH)2–4‐t‐BuC6H2}2C5H3N]CoCl2 (Co6) is also reported. All cobaltous complexes are paramagnetic and have been characterized by 1H/19F NMR spectroscopy, FT‐IR spectroscopy and elemental analysis. The molecular structures of Co3 and Co6 highlight the different degrees of steric protection given to the metal center by the particular N‐aryl group combination. Depending on the aluminoxane co‐catalyst employed to activate the cobalt precatalyst, distinct variations in thermal stability and activity of the catalyst towards ethylene polymerization were exhibited. In particular with MAO, the resultant catalysts reached their optimal performance at 70 °C delivering high activities of up to 10.1 × 106 g PE (mol of Co)−1 h−1 with Co1 > Co4 > Co2 > Co5 > Co3 >> Co6. On the other hand, using MMAO, the catalysts operate most effectively at 30 °C but are by comparison less productive. In general, the polyethylenes were highly linear, narrowly disperse and displayed a wide range of molecular weights [Mw range: 18.5–58.7 kg mol−1 (MAO); 206.1–352.5 kg mol−1 (MMAO)].
A Series of Ti6 Oxo Clusters Anchored with Arylamine Dyes: Effect of Dye Structures on Photocurrent Responses
Authors: Cui Li‐Na , Liu Pei‐Yi , Yang Lei , Shu Xian‐Ping , Zhu Qin‐Yu , Dai Jie 
Published: August 2019

AbstractDye molecules pre‐anchored on titanium oxo clusters (dye‐TOCs) are attractive as model compounds of dye‐sensitized titanium oxide. To investigate the effects of the dye ligand structures of the dye‐TOCs on photocurrent conversion, a series of dye‐TOCs with the same Ti6 core structure and different antenna ligands (L) was synthesized and characterized crystallographically. The TOCs have the same structural formula of [Ti6O4L2(O3PPh)2(OiPr)10]. Two types of dyes with para‐ or meta‐substituted structures were designed and used as the ligands. The results show that charge transfer from the donor group to the TiO core of the TOCs with the para‐substituted ligands is stronger than those with the meta‐substituted ligands. The steric effect of the ligands also greatly influences the photocurrent density. Larger branched structures of the dye ligands reduce the coverage density of the dye‐TOCs on TiO2 electrodes and also weaken the effective covalent bonding of the dye‐TOCs on the electrode, and consequently, the photocurrent is decreased.
Dual emission carbon dots from carotenoids: Converting a single emission to dual emission
Authors: Konwar Achyut , Deb Ankita , Kar Archita , Chowdhury Devasish 
Published: August 2019

AbstractDual emission carbon dots have a high potential for use as fluorescence‐based sensors with higher selectivity and sensitivity. This study demonstrated the possibility of conversion of a biological molecular system with a single emission peak to a double emission carbon dots system. This report is the first to describe the synthesis of dual emission carbon dots by tuning the electronic environment of a conjugated system. Here we prepared carbon dots from a natural extract, from which carotenoids were used as a new source for carbon dots. Formation of the carbon dots was confirmed by images obtained under a transmission electron microscope as well as from a dynamic light scattering study. The prepared carbon dots system was characterized and its optical property was monitored. The study showed that, after irradiation with microwaves, the fluorescence intensity of the whole system changed, without any change in the original peak position of the carotenoid but with the appearance of an additional peak. A Fourier transform infrared study confirmed breaking of the conjugated system. When using ethylene glycol as a surface passivating agent added to these carotenoid carbon dots, the dual emission spectra became more distinct.
Alles fließt?
Authors: Schneppenheim Reinhard , Brehm Maria Alexandra 
Published: August 2019

ZusammenfassungDer von‐Willebrand‐Faktor ist ein zentrales Protein für die normale Hämostase mit unterschiedlichen strukturellen und funktionellen Domänen. Er bildet mit der Bindung an das exponierte Kollagen verletzter Gefäße und Thrombozyten mit deren Rezeptoren GPIb und GPIIb/IIIa die Matrix für den Ablauf der nachfolgenden Blutgerinnung. Quantitative und qualitative Defekte des VWF korrelieren mit dem von‐Willebrand‐Syndrom, der häufigsten Blutungsneigung, während das Fehlen der spezifischen VWF‐spaltenden Protease ADAMTS13 mit einer lebensbedrohlichen Mikroangiopathie assoziiert ist. Die Bedeutung des VWF für das Auftreten von Herzinfarkten und Schlaganfällen ist Gegenstand der aktuellen Forschung.
Das alpha‐Toxin von Staphylococcus aureus
Authors: Hildebrandt Jan‐Peter , Ziesemer Sabine , Möller Nils 
Published: August 2019

ZusammenfassungBeim gesunden Menschen ist eine oberflächliche Besiedlung mit Staphylokokken meist harmlos, weil die Abwehrmechanismen das bakterielle Wachstum kontrollieren. Ohne dass man die relevanten Umstände genau kennt, können solche zunächst kommensalen Bakterien den Wirt allerdings krank machen, indem sie sich lokal vermehren und sog. Virulenzfaktoren bilden, die ihnen pathogene Eigenschaften verleihen. Einer der potentesten Virulenzfaktoren von Staphylococcus aureus ist das alpha‐Toxin (Hämolysin A, Hla). Dieses Toxin bildet in den betroffenen Zellen des Wirtes Plasmamembran‐durchspannende Poren aus, deren Durchmesser den Durchtritt von Ionen und kleinen organischen Molekülen erlaubt. Dies stört die normale Zellfunktion, verändert die intrazelluläre Signaltransduktion und beeinträchtigt, besonders in Epithelzellen, das Aktin‐Zytoskelett und den Zusammenhang des Zellverbandes. Diese Prozesse könnten erklären, warum S. aureus einer derjenigen Keime ist, die sehr häufig an der Entstehung von Lungenentzündungen (Pneumonien) beteiligt sind.
Facile Synthesis of Fe/N/S‐Doped Carbon Tubes as High‐Performance Cathode and Anode for Microbial Fuel Cells
Authors: Yang Wei , Li Jun , Lan Linghan , Li Zhuo , Wei Wenli , Lu Jia En , Chen Shaowei 
Published: August 2019

AbstractAs a renewable energy technology, microbial fuel cell (MFC) has been attracting increasing attention in recent decades. However, practical applications of MFCs has been hampered by the unsatisfactory electrode performance, in particular, at the cathode. Herein, Fe/N/S‐doped carbon hollow tubes were prepared by a facile two‐stage procedure involving hydrothermal treatment and pyrolysis at controlled temperatures. Electrochemical studies showed that the obtained samples exhibited an apparent electrocatalytic activity towards oxygen reduction reaction in both alkaline and acidic media, a performance comparable to that of commercial Pt/C, and the sample prepared at 800 °C stood out as the best among the series with a half‐wave potential of +0.81 V vs. RHE and an electron transfer number of 3.98 at +0.6 V vs. RHE. The Fe/N/S‐doped carbon tubes also exhibited a remarkable performance as an MFC anode by facilitating bacterial growth and electron transfer between the biofilm and electrode. In fact, an MFC based on the carbon tubes as both cathode and anode showed a markedly higher performance (maximum power density 479 W m−3) than the control MFC based on a graphene aerogel anode and Pt/C cathode (359 W m−3). These results suggest that Fe/N/S‐doped carbon composites can be used for the fabrication of high‐efficiency MFC electrodes.
A Comprehensive Quantitative Assay for Amine Transaminases
Authors: Cairns Ryan , Gomm Andrew , Peel Christopher , Sharkey Michael , O'Reilly Elaine 
Published: August 2019

AbstractThe development of effective high‐throughput screening assays has contributed greatly to the wealth of designer enzymes available, by enabling rapid identification of desired variants from large mutant libraries. Here, we report a general and operationally simple end‐point assay for transaminases that enables the screening of both amine donors and acceptors in liquid phase. The spectrophotometric‐based screen exploits the amine donor 2‐aminoethylaniline (2‐AEA) and relies on reaction of in situ generated indole with Ehrlich's reagent. The assay has also been adapted to allow screening in the reverse direction by addition of indole and subsequent spectrophotometric analysis. Importantly, the screen provides qualitative information on the enantio‐preference of the individual biocatalysts. To increase the assay throughput, an engineered expression strain (E. coli BL21(DE3) ΔtnaA) lacking tryptophanase activity, was generated to enable reliable and direct evaluation of individual colonies arrayed on agar plates.
Cyclobishelicenes: Shape‐Persistent Figure‐Eight Aromatic Molecules with Promising Chiroptical Properties
Authors: Robert Antoine , Naulet Guillaume , Bock Harald , Vanthuyne Nicolas , Jean Marion , Giorgi Michel , Carissan Yannick , Aroulanda Christie , Scalabre Antoine , Pouget Emilie , Durola Fabien , Coquerel Yoann 
Published: August 2019

AbstractCyclobis[n]helicenes (n=3 or 5) are chiral D2‐symmetric π‐conjugated macrocycles with stable lemniscular, or figure‐eight, shapes. The conformational analysis of five different cyclobis[n]helicenes revealed that these molecules can only exist as their lemniscular conformers with high barriers to enantiomerization (>200 kJ mol−1). The enantiomers of a cyclobis[5]helicene were resolved by HPLC and their unusual chiroptical properties were attributed to the inherent chirality of their macrocyclic figure‐eight.
Redox‐mediated Negative Differential Resistance (NDR) Behavior in Perylenediimide Derivative: A Supramolecular Approach
Authors: Khurana Raman , Mohanty Jyotirmayee , Padma Narayanan , Barooah Nilotpal , Bhasikuttan Achikanath C. 
Published: August 2019

AbstractDeaggregated perylenediimide (PDI) derivatives exhibit exceptionally high quantum yields, photostability and appropriate molecular features for organic electronics. This work demonstrates a metal–dye–metal framework with a large and stable negative differential resistance (NDR) at ambient conditions, built using a supramolecular strategy. The deaggregation achieved through the encapsulation of the bay‐substituted phenyl groups of aggregated (l/d)‐Phe‐PDI dyes by the β‐CD macrocyclic host is validated through detailed spectroscopic and imaging techniques. The host–guest interaction resulted in a dramatic enhancement in the emission yield from 0.28 to 0.90. In the thin film deposits, the β‐CD/(l/d)‐Phe‐PDI complex displayed well‐connected sheet‐like morphology, whereas the uncomplexed (l/d)‐Phe‐PDI dye remained as scattered lumps. The large and reversible I–V characteristics displaying strong NDR behavior is attributed to the oxidation/reduction processes involving the rigid π‐rich PDI core and is stable at least for about six months at ambient conditions, a promising system for organic electronics applications.
A Low‐Temperature Approach for the Phase‐Pure Synthesis of MIL‐140 Structured Metal–Organic Frameworks
Authors: Schulz Marcel , Marquardt Nele , Schäfer Malte , Warwas Dawid Peter , Zailskas Saskia , Schaate Andreas 
Published: August 2019

AbstractIn a systematic investigation, the synthesis of metal–organic frameworks (MOFs) with MIL‐140 structure was studied. The precursors of this family of MOFs are the same as for the formation of the well‐known UiO‐type MOFs although the synthesis temperature for MIL‐140 is significantly higher. This study is focused on the formation of Zr‐based MIL‐140 MOFs with terephthalic acid (H2bdc), biphenyl‐4,4′‐dicarboxylic acid (H2bpdc), and 4,4′‐stilbenedicarboxylic acid (H2sdc) and the introduction of synthesis field diagrams to discover parameters for phase‐pure products. In this context, a MIL‐140 network with H2sdc as linker molecule is first reported. Additionally, an important aspect is the reduction of the synthesis temperature to make MIL‐140 MOFs more accessible even though linkers with a more delicate nature are used. The solvothermal syntheses were conducted in highly concentrated reaction mixtures whereby a targeted synthesis to yield the MIL‐140 phase is possible. Furthermore, the effect of the often‐used modulator approach is examined for these systems. Finally, the characteristics of the synthesized MOFs are compared with physisorption measurements, thermogravimetric analyses, and scanning electron microscopy.
A Closed Chemobrionic System as a Biochemical Delivery Platform
Authors: Angelis Georgios , Zayed Dimitris Nabil , Karioti Anastasia , Lazari Diamanto , Kanata Eirini , Sklaviadis Theodoros , Pampalakis Georgios 
Published: August 2019

AbstractInorganic cells bearing calcium silicate membranes were prepared and resembled closed chemical gardens. It was demonstrated that these inorganic cells can successfully be loaded with natural products, proteins and plasmid DNA, and their cargo can be released in a controlled manner. These cells demonstrated the ability of chemical gardens to act as platforms for the sustained delivery of biomolecules and are expected to introduce chemical gardens in the field of biosciences.
Macrocycle‐Directed Construction of Tetrahedral Anion–π Receptors for Nesting Anions with Complementary Geometry
Authors: Luo Jian , Zhu Jun , Tuo De‐Hui , Yuan Qinqin , Wang Lei , Wang Xue‐Bin , Ao Yu‐Fei , Wang Qi‐Qiang , Wang De‐Xian 
Published: August 2019

AbstractManipulation of the emerging anion–π interactions in a highly cooperative manner through sophisticated host design represents a very challenging task. In this work, unprecedented tetrahedral anion–π receptors have been successfully constructed for complementary accommodation of tetrahedral and relevant anions. The synthesis was achieved by a macrocycle‐directed approach by using large macrocycle precursors bearing four reactive sites, which enabled a kinetic‐favored pathway and afforded the otherwise inaccessible tetrahedral cages in considerable yields. Crystal structure suggested that the tetrahedral cages have an enclosed three‐dimensional cavity surrounded by four electron‐deficient triazine faces in a tetrahedral array. The complementary accommodation of a series of tetrahedral and relevant anions including BF4−, ClO4−, H2PO4−, HSO4−, SO42− and PF6− was revealed by ESI‐MS and DFT calculations. Crystal structures of ClO4− and PF6− complexes showed that the anion was nicely encapsulated within the tetrahedral cavity with up to quadruple cooperative anion–π interactions by an excellent shape and size match. The strong anion–π binding was further confirmed by negative ion photoelectron spectroscopy measurements.
Electrochemical Behavior of Ti3C2Tx MXene in Environmentally Friendly Methanesulfonic Acid Electrolyte
Authors: Zhao Xin , Dall'Agnese Chunxiang , Chu Xue‐Feng , Zhao Shuangshuang , Chen Gang , Gogotsi Yury , Gao Yu , Dall'Agnese Yohan 
Published: August 2019

AbstractTwo‐dimensional transition metal carbides, nitrides, and carbonitrides, called MXenes, have gained much attention as electrode materials in electrochemical energy storage devices. In particular, Ti3C2Tx has shown outstanding performance in common sulfuric acid (H2SO4) electrolyte. In this work, a more environmentally friendly alternative acidic electrolyte, methanesulfonic acid (MSA), is proposed. The energy storage performance of Ti3C2Tx in aqueous and neat MSA ionic liquid electrolytes is investigated. The specific capacitance of 298 F g−1 was obtained at a scan rate of 5 mV s−1 in 4 m MSA and it exhibits excellent cycle stability with retention of nearly 100 % over 10 000 cycles. This electrochemical performance is similar to that of Ti3C2Tx in H2SO4, but using a greener electrolyte. In situ X‐ray diffraction analysis reveals the intercalation charge storage mechanism. Specifically, the interlayer spacing changes by up to 2.58 Å during cycling, which is the largest reversible volume change observed in MXenes in aqueous electrolytes.
Probing disrupted neurodevelopment in autism using human stem cell‐derived neurons and organoids: An outlook into future diagnostics and drug development
Authors: Yang Guang , Shcheglovitov Alex 
Published: August 2019

AbstractAutism spectrum disorders (ASDs) represent a spectrum of neurodevelopmental disorders characterized by impaired social interaction, repetitive or restrictive behaviors, and problems with speech. According to a recent report by the Centers for Disease Control and Prevention, one in 68 children in the US is diagnosed with ASDs. Although ASD‐related diagnostics and the knowledge of ASD‐associated genetic abnormalities have improved in recent years, our understanding of the cellular and molecular pathways disrupted in ASD remains very limited. As a result, no specific therapies or medications are available for individuals with ASDs. In this review, we describe the neurodevelopmental processes that are likely affected in the brains of individuals with ASDs and discuss how patient‐specific stem cell‐derived neurons and organoids can be used for investigating these processes at the cellular and molecular levels. Finally, we propose a discovery pipeline to be used in the future for identifying the cellular and molecular deficits and developing novel personalized therapies for individuals with idiopathic ASDs.
Genome‐wide association analyses reveal polygenic genomic architecture underlying divergent shell morphology in SpanishLittorina saxatilisecotypes
Authors: Kess Tony , Boulding Elizabeth G. 
Published: August 2019

AbstractGene flow between diverging populations experiencing dissimilar ecological conditions can theoretically constrain adaptive evolution. To minimize the effect of gene flow, alleles underlying traits essential for local adaptation are predicted to be located in linked genome regions with reduced recombination. Local reduction in gene flow caused by selection is expected to produce elevated divergence in these regions. The highly divergent crab‐adapted and wave‐adapted ecotypes of the marine snailLittorina saxatilispresent a model system to test these predictions. We used genome‐wide association (GWA) analysis of geometric morphometric shell traits associated with microgeographic divergence between the twoL. saxatilisecotypes within three separate sampling sites. A total of 477 snails that had individual geometric morphometric data and individual genotypes at 4,066 single nucleotide polymorphisms (SNPs) were analyzed using GWA methods that corrected for population structure among the three sites. This approach allowed dissection of the genomic architecture of shell shape divergence between ecotypes across a wide geographic range, spanning two glacial lineages. GWA revealed 216 quantitative trait loci (QTL) with shell size or shape differences between ecotypes, with most loci explaining a small proportion of phenotypic variation. We found that QTL were evenly distributed across 17 linkage groups, and exhibited elevated interchromosomal linkage, suggesting a genome‐wide response to divergent selection on shell shape between the two ecotypes. Shell shape trait‐associated loci showed partial overlap with previously identified outlier loci under divergent selection between the two ecotypes, supporting the hypothesis of diversifying selection on these genomic regions. These results suggest that divergence in shell shape between the crab‐adapted and wave‐adapted ecotypes is produced predominantly by a polygenic genomic architecture with positive linkage disequilibrium among loci of small effect.
Flow field characters near fracture entrance in supercritical carbon dioxide sand fracturing
Authors: Song Weiqiang , Zhang Junming , Wang Chunguang , Chen Shaojie , Chen Zhongwei 
Published: August 2019

AbstractTo investigate the flow field near fracture entrance and promote the development of sand fracturing with carbon dioxide as the working fluid, numerical simulation of multiphase flow was conducted with a 3D geological model considering the compressibility of carbon dioxide. The flow field of carbon dioxide alone was firstly investigated to lay the foundation for the analysis of multiphase flow, and then comparative analysis was conducted on the flow field of both the injecting sand from the pipe and the annulus. The results show that jet fracture with carbon dioxide can achieve a 4.46 MPa pressure boost at the fracture tip compared to the annulus pressure, which theoretically validates the feasibility of the mentioned technology. Sand fracturing can achieve a higher pressure boost in the cavity, while it needs greater pump pressure at the surface. Injecting sand from the annulus could decrease the need for pump pressure by 6.62 MPa at the condition of injecting 25% carbon dioxide from the annulus simultaneously, while the pressure difference between the cavity tip and the annulus decreases as a result. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.