Pyridyl phosphonium salts react with cyanopyridines and B2pin2 to form 2,4‐bipyridines with complete regiocontrol. Mechanistic studies support a radical–radical coupling process between two boryl‐stabilized pyridyl radical anions rather than a Minisci‐type pathway, and the process is unique to pyridyl phosphonium salts. Abstract A pyridine–pyridine coupling reaction has been developed between pyridyl phosphonium salts and cyanopyridines using B2pin2 as an electron‐transfer reagent. Complete...
Mon Sep 09, 2019 21:22
The fast and reversible switching of plasmonic color holds great promise for many intriguing applications, while its realization has been mainly limited to solution phases where plasmonic coupling could be conveniently enabled by manipulating the interactions among the plasmonic metal nanoparticles. Achieving solid‐state plasmonic color‐switching has remained a significant challenge due to the lack of effective strategies in dynamically controlling the nanoparticle separation and their plasmonic...
Mon Sep 09, 2019 19:46
Graphene‐based materials still exhibit poor electrocatalytic activities for hydrogen evolution reaction (HER) although they are considered to be the most promising electrocatalysts. Herein, we first fabricated a graphene analogous material displaying exceptional activity toward HER in acidic conditions with an overpotential (57 mV at 10 mA cm‐2) and Tafel slope (44.6 mV dec‐1) superior among the reported graphene‐based materials, even comparable to the state‐of‐the art Pt/C catalyst. X‐ray absorption...
Mon Sep 09, 2019 19:22
We herein present a metal‐free, electrosynthetic method that enables direct dehydrogenative coupling reactions of phenols carrying electron‐withdrawing groups for the first time. The reactions are easy to conduct and scalable, as they are carried out in undivided cells and obviate the necessity for additional supporting electrolyte. As such, this conversion is efficient, practical and thereby environmentally‐friendly, as production of waste is minimized. The method features a broad substrate scope,...
Mon Sep 09, 2019 17:24
While the introduction of polymers in aerogels strongly enhances their toughness, truly elastic monolithic aerogels able to restore their dimensions upon extensive compression are still challenging to synthesize. In this context hydrophobic semi‐crystalline polymers with low glass transition temperatures that combine both stiffness and flexibility have only recently gained attention. We show that polyethylene aerogels with low density combining chemical crosslinking and high crystallinity display...
Mon Sep 09, 2019 17:22
Transition‐Metal Chemistry of Alkaline‐Earth Elements: The Trisbenzene Complexes M(Bz)3 (M = Sr, Ba)
We report the synthesis and spectroscopic identification of the trisbenzene complexes of strontium and barium M(Bz)3 (M = Sr, Ba) in low‐temperature Ne matrix. Both complexes are characterized by a D3 symmetric structure involving three equivalent η6‐bound benzene ligands and a closed‐shell singlet electronic ground state. The analysis of the electronic structure shows that the complexes exhibit metal‐ligand bonds that are typical for transition metal compounds. The chemical bonds can be explained...
Mon Sep 09, 2019 15:30
As a class of metal‐free NRR photocatalysts, g‐C3N4 possesses advantageous features of scalable‐synthesis at low cost. Importantly, it can be readily functionalized to enhance photocatalytic activities. However, the use of g‐C3N4 based photocatalysts for the N2 reduction reaction (NRR) has been seriously doubted because of the elusive NRR mechanism and the involvement of N defects. This work reported the synthesis of a cyano groups and K+ intercalation modified g‐C3N4 (mCNN) photocatalyst with extended...
Mon Sep 09, 2019 15:28
Using amber‐codon suppression, N ϵ ‐acryloyl‐lysine was genetically encoded in a phage‐displayed peptide library for cyclization with a pre‐installed cysteine. Selection from this phage‐display library afforded cyclic peptides that bind TEV protease and histone deacetylase, HDAC8, much stronger than their linear counterparts. Abstract Superior to linear peptides in biological activities, cyclic peptides are considered to have great potential as therapeutic agents. To identify cyclic‐peptide...
Mon Sep 09, 2019 14:10
Come on over vinylene: The synthesis of two vinylene‐linked (−CH=CH−) covalent organic frameworks (COFs) by base‐catalyzed aldol condensation is reported. Structural properties of the highly crystalline COF were investigated. Abstract Two 2D covalent organic frameworks (COFs) linked by vinylene (−CH=CH−) groups (V‐COF‐1 and V‐COF‐2) are synthesized by exploiting the electron deficient nature of the aromatic s‐triazine unit of C3‐symmetric 2,4,6‐trimethyl‐s‐triazine (TMT). The acidic terminal...
Mon Sep 09, 2019 14:08
High five! Prolonged thermal pyrolysis of hemin (H) and melamine (M) on graphene (G) provided a robust single‐iron‐atom electrocatalyst for CO2 reduction. The single‐atom catalyst exhibited high Faradaic efficiency (ca. 97 %) for CO production at low overpotential (0.35 V) owing to the presence of highly efficient dispersed FeN5 active sites supported on N‐doped graphene through an additional axial ligand coordinated to FeN4 (see picture; Fe red, N blue). Abstract Electrochemical conversion...
Mon Sep 09, 2019 14:07
The selenium isolog of the natural antioxidant ergothioneine, selenoneine and other 2‐selenoimidazoles are synthesized. Distinct reactivities are found for selenoneine and ergothioneine, showing that the two compounds can fill distinct functional niches. Synthetic access to 2‐selenoimidazoles paves the way to explore the pharmaceutical potential and physiological function of this heretofore inaccessible class of compounds. Abstract The N‐α‐trimethyl 2‐selenohistidine selenoneine is the selenium...
Mon Sep 09, 2019 13:45
Size matters: Coordination isomerism was exploited for the first time to control the morphology of a supramolecular polymer. These observations pave the way for novel stimuli‐responsive materials and offer a new approach for size control in self‐assembled systems. Abstract We exploited the inherent geometrical isomerism of a PtII complex as a new tool to control supramolecular assembly processes. UV irradiation and careful selection of solvent, temperature, and concentration leads to tunable...
Mon Sep 09, 2019 13:38
Ring assembly: An effective diastereoselective spiroketalization has been realized for a broad range of aldehydes and proceeds in the presence of a copper catalyst. This method was applied to the total synthesis of (+)‐broussonetine G and formal synthesis of (+)‐broussonetine H. Abstract A highly diastereoselective copper‐catalyzed multicomponent cyclization of exocyclic enol ethers/enamines with methylene malonate and aldehydes has been developed to furnish spiroheterocyclic tetrahydropyrans...
Mon Sep 09, 2019 13:32
A dendrite‐free zinc plating behavior was achieved by combining a Cu‐Zn solid solution interface on a copper mesh skeleton and polyacrylamide electrolyte additive. The zinc ion has strong selective adsorption on the acyl group of polyacrylamide and can be transferred along the polymer chains, leading to the homogeneous zinc distribution. Abstract Rechargeable aqueous zinc‐ion batteries have been considered as a promising candidate for next‐generation batteries. However, the formation of zinc...
Mon Sep 09, 2019 11:21
Walking in drops: In this work, a super‐multiplexed coding technology based on stochastic DNA walkers in droplets for ultrahigh‐throughput bacterial detection is developed. Abstract Pathogen detection is growing in importance in the global health arena because of the high morbidity and mortality associated with bacterial blood stream infections. In this work, we present stochastic DNA walkers in droplets (SDwalker‐Drop), a one‐step, rapid, and super‐multiplex method for ultrahigh‐throughput...
Mon Sep 09, 2019 11:14
Single‐atom strength: An anionic fluorenyl complex of Ni0 is capable of alkane dehydrogenation via C−H activation in the gas phase. Sequential dehydrogenations can transform cyclohexane into benzene. DFT calculations and kinetic isotope effects support the proposed mechanism. This metal complex serves as an experimental model for graphene‐supported single‐atom catalysis. Abstract A gas‐phase anionic nickel(0) fluorenyl complex is shown to effect the dehydrogenation of linear, branched, and...
Mon Sep 09, 2019 11:12
A unique chelation‐assisted, inner‐sphere pathway for the Pd‐catalyzed allylic amination of vinyl cyclic carbonates with aryl amines was revealed by DFT calculations and various experiments. A chelation effect enabled through a η2‐coordination of the N‐aryl group to the Pd centre was identified as a key interaction with profound implication for the selectivity parameters. Abstract A recently reported palladium‐catalyzed allylic substitution of vinyl‐substituted cyclic carbonates (VCCs) with...
Mon Sep 09, 2019 11:06
The potassium‐ion storage performance of a NiCo2.5S4 composite electrode improves in a potassium bis(fluorosulfonyl) imide, ethylene and propylene carbonate mixed electrolyte (KFSI‐EP, EPF (doped with fluoroethylene carbonate)). Performance declines in KPF6‐ or fluoroethylene‐carbonate‐containing electrolytes. A robust solid electrolyte interphase layer increases performance in a potassium‐ion battery. Scale: 10 μm. Abstract Metal–organic framework‐derived NiCo2.5S4 microrods wrapped in reduced...
Mon Sep 09, 2019 11:02
Chiral sulfones moving forward: The first general, Pd‐catalyzed asymmetric synthesis of α,α‐disubstituted allylic sulfones has been realized. This process is based on a Tsuji–Trost allylic alkylation using both alkyl‐ and arylsulfinate based nucleophiles and a new phosphoramidite ligand and was successfully applied to the formal synthesis of the sesquiterpene (−)‐Agelasidine A. Abstract We describe here the first general asymmetric synthesis of sterically encumbered α,α‐disubstituted allylic...
Mon Sep 09, 2019 11:01
The oscillatory polarization state of a nano‐ferroelectric with the coexistence of three ferroelectric phases (T+O+R) leads to an imbalanced charge state on the sample surface and creates an alternating cascade of a space charge release and attraction under ultrasonic vibration, thus generating hydrogen and oxygen via direct water decomposition. Abstract Piezocatalysis, converting mechanical vibration into chemical energy, has emerged as a promising candidate for water‐splitting technology....
Mon Sep 09, 2019 11:01
Tetraarylethenes are obtained by acid‐induced coupling of vinyl triazenes with aromatic compounds. This new C‐H activation route for the synthesis of aggregation‐induced emission luminogens is simple, fast, and versatile. It allows the direct grafting of triarylethenyl groups on a variety of aromatic compounds, including heterocycles, supramolecular hosts, biologically relevant molecules, and commercial polymers.
Sun Sep 08, 2019 21:23
CO2 conversion into valuable molecules has emerged as a field of intensive investigation, with the aim of ultimately developing scalable technologies for making fuels using renewable sources of energy. Electrochemically reduction into CO and formate getting closer from industrial maturity, the challenge is now to obtain more reduced products like methanol, an already commercialized fuel. At the contrary, literature is really scarce on the matter, and even more when using molecular catalyst. Here,...
Sun Sep 08, 2019 21:03
The all‐cis stereoisomers of tetrasubstituted azetidine‐2‐carboxylic acids and derivatives that possess three chiral centers have been prepared in high yield and stereocontrol from silyl‐protected Z‐γ‐substituted enoldiazoacetates and imido‐sulfur ylides by asymmetric [3+1]‐cycloaddition using chiral sabox copper(I) catalysis followed by Pd/C catalytic hydrogenation. Hydrogenation of the chiral p‐methoxybenzyl azetine‐2‐carboxylates occurs with both hydrogen addition to the C=C bond and hydrogenolysis...
Sun Sep 08, 2019 16:45
The rediscovery of graphene in 2004 has started an enormous chase in the research of 2D materials. A new family of layered 2D materials consisting of the 14th group elements beyond carbon has already been reported. Here, a new methodology in germanene chemistry is presented using germanane (Ge 6 H 6 ) as a stable and easily accessible starting material for effective synthesis of novel germanene derivatives. The modification procedure utilizing strong bases – alkali metal arenides – for deprotonation...
Sun Sep 08, 2019 16:43
Abstract Purpose To evaluate the accuracy of three‐dimensional (3D) printed models manufactured using two different printer technologies with different model base designs. Materials and Methods A maxillary typodont was scanned using a desktop scanner to generate the Standard Tessellation Language (STL) file as a reference scan. After the scanning procedure, the STL file was exported to Model Builder™ for designing the following two types of the model bases: a solid base design and a hollow...
Mon Sep 09, 2019 20:09
Abstract Primary lymphoepithelioma-like carcinoma of the skin (LELCS) is a very rare cutaneous neoplasm. Only about 70 cases have been documented in the literature. There are no prospective data regarding treatment methods. Surgical excision is sufficient therapy in the majority of cases. Radiation therapy is sometimes used in case of recurrence or positive margins after surgery. The metastatic potential of LELCS is extremely low and only five previously documented cases of lymph...
Mon Sep 09, 2019 03:00
Abstract Purpose The proximal approach to the small saphenous vein (SSV) must be performed according to precise anatomical landmarks to respect the esthetic profile of venous insufficiency surgery. In this work, we propose the tip of the lateral malleolus and the lateral edge of the calcaneal tendon as palpable landmarks from which to easily identify the situation of this vein. ...
Mon Sep 09, 2019 03:00
Abstract Background Acromegaly is a rare disease caused by an excess of growth hormone and insulin-like growth factor 1. It is usually diagnosed because of typical signs such as macroglossia, acral enlargement, jaw prognathism and malocclusion. Systemic complications are a major cause of morbidity and mortality in acromegaly, and many patients remain undiagnosed for several years. Increased ultrasound (US) application in the general population,...
Mon Sep 09, 2019 03:00
Abstract Adverse ecological and social conditions during early life are known to influence development, with rippling effects that may explain variation in adult health and fitness. The adaptive function of such developmental plasticity, however, remains relatively untested in long‐lived animals, resulting in much debate over which evolutionary models are most applicable. Furthermore, despite the promise of clinical interventions that might alleviate the health consequences of early‐life adversity,...
Mon Sep 09, 2019 19:28
Zusammenfassung Fehler bei der Sammlung, Auswertung, Analyse und Publikation von Daten geschehen oft nicht zuletzt deshalb, weil das methodische Problembewusstsein fehlt. Sie können weitreichende Folgen für die Rezeption der Ergebnisse wissenschaftlicher Primärstudien und in Folge dessen auch für die klinische Praxis und die Gesundheitsversorgung haben. Der vorliegende Artikel versteht sich als Beitrag zum verantwortungsvollen Umgang mit Studiendaten, zeigt exemplarisch einige...
Mon Sep 09, 2019 03:00
This study shows that human omental milky spots (OMSs) contain sympathetic nerve fibres. Often, these nerve fibres were located around small blood vessels and occasionally individual nerve fibres were observed between lymphoid cells. The presence of sympathetic fibres in OMSs contributes to our understanding of how OMS immune function might be regulated during an abdominal immune challenge and why they form primary implantation sites for peritoneal exfoliated cancer cells. Abstract Omental milky...
Mon Sep 09, 2019 18:33
Conditions: Head and Neck Cancer; TrismusInterventions: Combination Product: Photobiomodulation therapy with mandibular exercises; Combination Product: Sonophoresis with mandibular exercisesSponsor: Asir John SamuelNot yet recruiting
Mon Sep 09, 2019 19:00
Image description: Nell, a white woman with short black hair, wears thick, black-rimmed glasses and smiles at the camera. She also wears a collared, button-up shirt that is white with a dark quatrefoil pattern; a black and gold diagonal stripe bow tie; and a glass pendant necklace. She is outside on a sunny day and leans back on the concrete structure behind her.Nell Koneczny joined AAA in June 2019 as the new Accessibility and Meetings Coordinator. In this role, Nell is responsible for the development...
Mon Sep 09, 2019 18:35
An international team of researchers has found unusual genetic features in fungi of the order Trichosporonales.
Mon Sep 09, 2019 17:46
Pancreatic tumors and their surgical resection are associated with significant morbidity and mortality, and the biomarkers currently used for these conditions have limited sensitivity and specificity. Because calprotectin and calgranulin C serum levels have been demonstrated to be potential biomarkers of certain cancers and complications of major surgery, the levels of both proteins were tested in the current study in patients with benign and malignant pancreatic tumors that were surgically removed....
Mon Sep 09, 2019 17:05
Behçet’s disease (BD) is an autoinflammatory disease that can lead to life- and sight-threating complications. Dendritic cells (DCs) are the most potent antigen-presenting cells that can regulate multiple inflammatory pathways. The objective of this study was to investigate the association of the DC stimulatory molecule CD83 with BD. Frequencies of costimulatory molecules expressing DCs in peripheral blood leukocytes (PBL) were measured by flow cytometry (FACS). The severity of symptoms in HSV-1-induced...
Mon Sep 09, 2019 16:05
Cystic fibrosis (CF) is a genetic disease characterized by progressive decline of lung function and chronic airway inflammation. Adipose tissue, through adiponectin and leptin, exerts several effects on energy metabolism and inflammatory processes. This study evaluated the levels of adiponectin and leptin in adult healthy subjects, in patients with CF and their correlation with long-term physical activity. CF patients were divided into two groups (sedentary versus active) based on their regular physical...
Mon Sep 09, 2019 16:05
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