Some like it hot : Rhodium nanoparticles immobilized on an acid‐free triphenylphosphonium‐based supported ionic liquid phase (Rh@SILP(Ph3‐P‐NTf2)) enabled ready access to high‐value cyclohexane derivatives from aromatic ketones. The product distribution could be switched with high selectivity between the completely hydrogenated (alcohol) and hydrodeoxygenated (alkane) products by changing the reaction temperature (see scheme). Abstract Rhodium nanoparticles immobilized on an acid‐free triphenylphosphonium‐based...
Wed May 27, 2020 13:44
Molecular decoy : The Helicobacter pylori serotype O6 tridecasaccharide O‐antigen containing a terminal Ley tetrasaccharide and a unique dd ‐heptoglycan was chemically synthesized for the first time. Immunological investigation based on seven synthetic oligosaccharides revealed that the α‐(1→3)‐linked dd ‐heptoglycan is a key motif for designing glycoconjugate vaccines against H. pylori , while the Ley tetrasaccharide may serve as a decoy to the immune system. Abstract The development of glycoconjugate...
Wed May 27, 2020 13:43
Localized semiconductive areas are generated by thermal annealing of oxo‐functionalized graphene, by the formation of sp3‐patches isolating sp2‐graphene‐like structures. The semiconductive patches display a band gap of 0.4 eV. The discovery of the structural and electronic insights paves the way to novel semiconductors. Abstract The thermal decomposition of graphene oxide (GO) is a complex process at the atomic level and not fully understood. Here, a subclass of GO, oxo‐functionalized graphene...
Wed May 27, 2020 13:43
Just Labeled : Transition‐metal‐free carbon isotope exchange on phenyl acetic acids is described. Utilizing the universal precursor CO2, the carbon isotope can be inserted into the carboxylic acid position, with no need of precursor synthesis. This procedure enabled the labeling of 15 pharmaceuticals and was compatible with [14C] and [13C]. A proof of concept with [11C] was also obtained with low molar activity valuable for distribution studies. Abstract A transition‐metal‐free carbon isotope...
Wed May 27, 2020 13:43
Effects of distribution on performance : A single‐atom Fe electrocatalyst supported on nitrogen‐free lignocellulose‐derived graphitic carbon with Fe‐(O‐C2)4 active sites was synthesized and exceptional catalytic activity for N2 reduction to NH3 was demonstrated. The results indicate that the performance of a given catalyst is strongly influenced by factors other than its intrinsic electrocatalytic activity. Abstract Single‐atom catalysts have demonstrated their superiority over other types...
Wed May 27, 2020 13:43
There is a wave breaking over us —a wave of simulation and artificial intelligence. In three reflective Essays we make a case for true understanding, for scientific story‐telling, as well as a role for pleasure and the emotions within science in general and quantum chemistry in particular. Abstract We begin our tripartite Essay with a triangle of understanding, theory and simulation. Sketching the intimate tie between explanation and teaching, we also point to the emotional impact of understanding....
Wed May 27, 2020 13:43
Ring opening metathesis polymerization (ROMP) produces block copolymers in one‐step from the mixture of monomers with different steric demand having the highest difference in reactivity ratios ever observed for a copolymerization method. A reversible G3 Fischer‐carbene to G3 benzylidene/alkylidene transformation was used in the compositional analysis of these block copolymers. Abstract Using a one‐step synthetic route for block copolymers avoids the repeated addition of monomers to the polymerization...
Wed May 27, 2020 13:42
Electrons and ions : Aqueous zinc‐ion batteries are promising candidates for the next‐generation energy storage system. This Minireview summarizes the recent developments in the modification of the host–zinc and the zinc–electrolyte interfaces. Design strategies to fabricate dendrite‐free zinc anodes by optimizing the interfacial electron and ion distribution are discussed. Abstract Aqueous zinc‐ion batteries have rapidly developed recently as promising energy storage devices in large‐scale...
Wed May 27, 2020 13:39
It's all about the sterics : A base‐mediated imidization procedure under mild reaction conditions and stoichiometric amounts of reactants gives direct and easy access to sterically crowded naphthalene/perylene imides. The effects of the steric demand of the different substituents on the packing motifs and optical properties in the solid state are explored. Abstract We report the direct imidization of naphthalene and perylene dicarboxylic anhydrides/esters with bulky ortho ,ortho ‐diaryl‐ and...
Wed May 27, 2020 13:39
By involving a methyl ammonium acetate (MAAc) ionic liquid solvent, strong Pb−O interaction and N−H⋅⋅⋅I hydrogen bonds between MAAc and PbI2 lead to a controllable all‐inorganic perovskite formation in ambient air. The resulting solar cells exhibit high efficiency and excellent stability under continuous light illumination. Abstract All‐inorganic lead halide perovskites are promising candidates for optoelectronic applications. However, fundamental questions remain over the component interaction...
Wed May 27, 2020 13:38
A breed apart : The non‐ribosomal peptide synthetase (NRPS) XfpS, which produces the peptides xefoampeptides A and B, can be artificially split without loss of biosynthetic activity by introducing docking domains into XfpS. In fact, in this case, the production of both peptides from the split system increased compared to product levels from the full‐length XfpS. Splitting XfpS into three subunits also led to a functional NRPS system. Abstract The interaction in multisubunit non‐ribosomal peptide...
Wed May 27, 2020 13:35
Things fall apart : A smart perylene monoimide‐based nanocluster (FHP) capable of enzyme‐triggered disassembly is reported as an activatable nano‐photosensitizer. FHP disassembles into circa 10‐nm nanoparticles, simultaneously leading to deep tumor penetration, enhanced fluorescence intensity (ca. 8‐fold), and elevated singlet oxygen generation (ca. 4‐fold). Abstract Photodynamic therapy (PDT) exhibits great potential for cancer therapy, but still suffers from nonspecific photosensitivity and...
Wed May 27, 2020 13:35
A new metal–organic framework (MOF), based on infinite Ti−O chains and 4,4′,4′′,4′′′‐(pyrene‐1,3,6,8‐tetrayl)tetrabenzoic acid, shows great promise for a wide range of photocatalytic reactions, from hydrogen evolution to the selective oxidation of organic substrates. Abstract The one‐step synthesis and characterization of a new and robust titanium‐based metal–organic framework, ACM‐1 , is reported. In this structure, which is based on infinite Ti−O chains and 4,4′,4′′,4′′′‐(pyrene‐1,3,6,8‐tetrayl)...
Wed May 27, 2020 13:35
An earth‐abundant zirconium‐based catalyst has been developed for the selective 1,1‐diboration of bulk and inexpensive alkenes with a borane without the need for an additional H2 acceptor. Many aryl alkenes as well as long‐chain aliphatic alkenes convert smoothly into their corresponding 1,1‐diborylalkanes and the method also allows the unprecedented remote 1,1‐diboration of internal alkenes. Abstract A general and atom‐economical synthesis of 1,1‐diborylalkanes from alkenes and a borane without...
Wed May 27, 2020 13:34
Aromatic stabilization of both states : A molecular design concept for highly stable organic battery electrode materials is presented using the conjugated macrocycle [2.2.2.2]paracyclophane‐1,9,17,25‐tetraene (PCT). The compound can stabilize both the neutral and reduced state by aromaticity, enabling batteries with extraordinarily stable cycling performance and outstanding performance under fast‐charge/discharge conditions. Abstract Aromatic organic compounds can be used as electrode materials...
Wed May 27, 2020 13:34
Catalyst design : This Minireview summarizes the recent progress in early transition metal polymerization catalyst development, categorized by the catalytic metal complex and polar comonomer identity. Advances in the mechanistic understanding of these polymerizations are discussed, focusing on critical challenges and strategies that mitigate them. Abstract Introducing polar functional groups into widely used polyolefins can enhance polymer surface, rheological, mixing, and other properties,...
Wed May 27, 2020 13:33
All in a knot : A highly selective synthetic strategy, backbone‐directed self‐assembly, is realized. This method is used for the preparation of molecular cyclic metalla[3]catenanes. Abstract The efficient backbone‐directed self‐assembly of cyclic metalla[3]catenanes by the combination of tetrachloroperylenediimide (TCPDI)‐based dinuclear rhodium(III) clips and 4,4′‐diazopyridine or 4,4′‐dipyridylethylene ligands is realized in a single‐step strategy. The topology and coordination geometry of...
Wed May 27, 2020 13:33
Artificial Deprenylase : An oxoammonium cation has been identified as a unique chemical motif that targets prenylated i6A RNA and exhibits remarkable selectivity and efficiency in both live cells and plants. This demonstrates that small organic molecules as artificial enzyme mimics can be powerful tools to modulate RNA epigenetic modification for the precise control of biological events. Abstract N 6‐isopentenyladenosine (i6A) is an RNA modification found in cytokinins, which regulate plant...
Wed May 27, 2020 13:33
Live‐cell entropy‐driven multivalent DNA circuits as computing devices have been reported. Telomerase and two miRNAs act as the circuit triggers for single‐cell imaging analysis. Their signal outputs are encoded as multi‐bit binary codes to differentiate non‐tumorigenic, malignant and metastatic breast cells as well as respective tumors. Abstract Tumor progressions such as metastasis are complicated events that involve abnormal expression of different miRNAs and enzymes. Monitoring these biomolecules...
Wed May 27, 2020 13:33
DUBstep : A new class of deubiquitylase (DUB)‐resistant ubiquitin (Ub) probes, wherein an N ‐ethyl group is present at the isopeptide bonds, has been developed and used to study the Ub‐interacting (Ubi) proteome. This family of Ub probes can be efficiently prepared by an enzyme‐catalyzed chemoenzymatic strategy using readily available recombinant materials. Abstract Triazole‐based deubiquitylase (DUB)‐resistant ubiquitin (Ub) probes have recently emerged as effective tools for the discovery...
Wed May 27, 2020 13:33
Υπάρχει μία κίνηση που ασυναίσθητα επαναλαμβάνουμε πολλές φορές φορές στη διάρκεια της ημέρας, η οποία έχει αποδειχθεί άκρως επικίνδυνη για την υγεία μας, ιδίως τις ημέρες της πανδημίας COVID-19. Για τον νέο κορωνοϊό, γνωρίζουμε πως μεταδίδεται μέσω σταγονιδίων τα οποία επικάθονται στις επιφάνειες και μπορούν να επιβιώσουν για μεγάλα χρονικά διαστήματα. Αν αγγίξουμε αυτές τις επιφάνειες και έπειτα το πρόσωπό μας σε περιοχές όπως η μύτη και τα μάτια, αυξάνουμε τον κίνδυνο μόλυνσης. Πόσο συχνά λοιπόν...
Thu May 28, 2020 13:28
Η κλινική μελέτη Φάσης 3 IKEMA που αξιολογεί την προσθήκη του isatuximab στη θεραπεία με καρφιλζομίμπη και δεξαμεθαζόνη πέτυχε το πρωτεύον καταληκτικό σημείο κατά την πρώτη προγραμματισμένη ενδιάμεση ανάλυση, καταδεικνύοντας σημαντικά παρατεταμένη επιβίωση χωρίς εξέλιξη της νόσου, σε σύγκριση με την καθιερωμένη θεραπεία με τον συνδυασμό καρφιλζομίμπης και δεξαμεθαζόνης, σε ασθενείς με υποτροπιάζον πολλαπλό μυέλωμα. Δεν παρατηρήθηκαν νέα ευρήματα ασφάλειας στη συγκεκριμένη μελέτη. Τα αποτελέσματα...
Wed May 27, 2020 13:10
Τι σκέφτεται κανείς όταν ακούει για ένα ζεστό μπάνιο; Σίγουρα, η αγαπημένη συνήθεια έχει συνδεθεί με τη χαλάρωση και την απόλαυση, ενώ δεν πρέπει να παραμερίζεται η συμβολή του στην ανακούφιση των πόνων των αρθρώσεων, στην απομάκρυνση του στρες και τη βελτίωση του ύπνου. Όπως έδειξε πρόσφατη έρευνα, τα οφέλη του δεν περιορίζονται εδώ. Σύμφωνα με νέα ευρήματα που δημοσιεύτηκαν στο Heart, ένα ζεστό μπάνιο καθημερινά βελτιώνει την υγεία της καρδιάς. Σε αυτό κατέληξαν οι ερευνητές έπειτα από τη συλλογή...
Thu May 28, 2020 08:50
Συγκεκριμένα, οι ερευνητές της Ιατρικής Σχολής του Πανεπιστημίου του Έξετερ και της αντίστοιχης του Πανεπιστημίου του Κονέκτικατ ανέλυσαν δεδομένα δεκάδων χιλιάδων ανθρώπων από το Ηνωμένο Βασίλειο και διαπίστωσαν υψηλό κίνδυνο σοβαρής μόλυνσης από COVID-19 μεταξύ των Ευρωπαίων που φέρουν δύο ελαττωματικά αντίγραφα του γονιδίου APOE (ονομάζεται e4e4). Ένα στα 36 άτομα ευρωπαϊκής καταγωγής έχει δύο ελαττωματικά αντίγραφα αυτού του γονιδίου, το οποίο είναι γνωστό ότι αυξάνει τους κινδύνους της νόσου...
Thu May 28, 2020 08:12
A photo‐organo‐iron‐catalyzed cyclotrimerization of alkynes has been developed that involves photoredox activation of a simple iron catalyst. The reaction operates under very mild conditions (visible light, 20 °C, 1 h) with 1–2 mol % loading of the triple catalyst system (organic dye, amine, and FeCl2). Abstract Successful combinations of visible‐light photocatalysis with metal catalysis have recently enabled the development of hitherto unknown chemical reactions. Dual mechanisms from merging...
Wed May 27, 2020 12:55
Development of artificial photosynthesis requires efficient water splitting catalysts. The short lived, six coordinated reactive intermediate [FeV=O,(OH)(Pytacn)]2+ competent in O−O bond formation was trapped. X‐ray absorption spectroscopy (XAS) confirmed FeV oxidation state and FeV=O bond at ≈1.60 Å. EPR and DFT revealed that this is the high spin FeV complex reacting via water nucleophilic attack to form the O−O bond. Abstract Hypervalent FeV=O species are implicated in a multitude of oxidative...
Wed May 27, 2020 12:53
Transient phosphenium and arsenium ions, generated by fluoride abstraction of bis( m ‐terphenyl)fluoropnictogens, underwent intramolecular electrophilic attack prior to methyl group migration and gave rise to isolable 9‐phospha‐ and 9‐arsena‐fluorenium ions.
Wed May 27, 2020 12:38
The notorious growth of Li dendrites is one of the main hindrances for the practical application of the lithium metal anode (LMA). In this work, a sulfur‐preloaded hollow nanostructure based on hierarchical MoS 2 coated hollow carbon particles (C@MoS 2 /S) was designed to modify the LMA. The C@MoS 2 hollow nanostructures serve as a good scaffold for repeated Li plating/stripping. More importantly, the encapsulated sulfur could gradually release lithium polysulfides during the Li plating/stripping...
Wed May 27, 2020 12:29
A facile one‐pot gram‐scale synthesis of tetraalkylammonium tetrafluoridochlorate(III) [cat][ClF 4 ] ([cat] = [NEt 3 Me] + , [NEt 4 ] + ) is described. An acetonitrile solution of the corresponding alkylammonium chloride salt is fluorinated with diluted fluorine at low temperatures. The reaction proceed via the [ClF 2 ] − anion which is structurally characterized for the first time. The potential application of [ClF 4 ] − salts as fluorinating agents is evaluated by the reaction...
Wed May 27, 2020 11:55
Co‐based Single Atom Site Catalysts with High Stability for Selective Dehydrogenation of Formic Acid
MOF‐derived Co‐N‐C catalysts with isolated single cobalt atoms have been synthesized and compared with cobalt nanoparticles for formic acid dehydrogenation. The atomically dispersed Co‐N‐C catalyst achieves superior activity, better acid resistance and improved long‐term stability compared with nanoparticles synthesized by a similar route. HAADF‐STEM, XPS, EPR and XAFS characterizations reveal the formation of Co(II)Nx centers as active sites. The optimal low‐cost catalyst is a promising candidate...
Wed May 27, 2020 11:30
Since their prediction in 1998 , guest‐induced structural transitions in 3 rd generation porous coordination polymers (PCPs) have changed common understanding on the adsorption properties of porous solids. By 2009, the chemistry of local and global dynamic behavior in crystalline porous solids received tremendous interest, with the studies linked under soft porous crystals (SPCs) . Since then, another decade has passed and novel phenomena in SPCs have emerged that require evaluation, particularly...
Wed May 27, 2020 11:01
Abstract Objective To evaluate the phenotypic features of the masticatory biomechanics in atypical subjects with Down syndrome (DS). Its influence was analyzed on sleep disorders, body adiposity and its risks, and some physicochemical properties of saliva. Methods Seventy subjects were enrolled to assess masticatory biomechanical function and divided into two groups: DS and control groups. Electrical activities of the masseter and temporal muscles (at rest and in maximum voluntary clench‐MVC),...
Thu May 28, 2020 11:31
Abstract Radiation-induced risks for all solid cancer incidence and mortality were studied in the cohort of Russian Chernobyl emergency workers. The cohort included 69,440 persons with documented individual radiation dose accrued over the time of working in the Chernobyl zone. The mean age at entry into the zone of recovery operations was 33.9 years and accumulated radiation dose was 132.9 mGy. A total of 6981 solid cancer incident cases and 4272 deaths occurred in this cohort...
Thu May 28, 2020 03:00
Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare, non-Hodgkin lymphoma which arises within the capsules of breast implants. These particular tumours have expression of CD30 and are negative for Anaplastic Lymphoma Kinase (ALK). Here, we report a case of BIA-ALCL in a 48-year-old woman post breast reconstruction. This case report is aimed at raising awareness and education on the significance of considering the development of BIA-ALCL in cases where cytology is negative...
Thu May 28, 2020 17:50
As the 2020 presidential campaign cycle intensifies, an increasing number of Americans will volunteer for political campaigns. Maybe you have volunteered or have interacted with a campaign volunteer via text message, email, telephone, or in person at your front door. Distinct from any other time in history, twenty-first century political campaigns in the United States explicitly focus on and foster these volunteer-voter interactions as they have been found to measurably impact voting behavior, including...
01:30
Abstract Background Non‐coding RNAs play a critical role in the occurrence and development of oral cancer. The present study is aimed to identify long non‐coding RNA (lncRNA) that might be novel effective targets for the treatments of oral cancer and the underlying mechanism. Methods The microarray profiling and RNA sequencing analysis were performed to identify lncRNAs related to oral cancer development and lncRNA DNM3OS was selected. DNM3OS knockdown was generated in cancer cell lines...
Thu May 28, 2020 20:03
Abstract Primary studies have presented conflicting results on the efficacy of Janus kinase (JAK) inhibitors in treating atopic dermatitis. Hence, it is important to determine the summary effect of JAK inhibitors in order to guide the clinical application of this potentially beneficial drug. To determine the efficacy of JAK inhibitors in treating atopic dermatitis in all age groups. A systematic review with meta‐analyses of randomized controlled trials (RCTs) reporting on the effect of JAK inhibitors...
Thu May 28, 2020 14:50
Wed May 27, 2020 22:55
Abstract Oral isotretinoin is frequently used in the treatment of young acne patients. However, knowledge levels and attitudes about this treatment have not been studied in the parents previously. We aimed to investigate the knowledge levels and concerns about oral isotretinoin in the parents of adolescent acne patients. We conducted a cross‐sectional study on 136 parents of adolescent patients with moderate to very severe acne vulgaris who answered the questionnaire about oral isotretinoin treatment....
Wed May 27, 2020 16:00
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