Abstract Purpose of Review Cardiac imaging after ischemic stroke or transient ischemic attack (TIA) is used to identify potential sources of cardioembolism, to classify stroke etiology leading to changes in secondary stroke prevention, and to detect frequent comorbidities. This article summarizes the latest research on this topic and provides an approach to clinical practice to use cardiac imaging after stroke. ...
Tue Jun 30, 2020 03:00
Abstract Purpose of Review The purpose of this article is to review the current approaches using neuroimaging techniques to expand eligibility for intravenous thrombolytic therapy in acute ischemic stroke patients with stroke of unknown symptom onset. Recent Findings In recent years, several randomized, placebo-controlled trials have...
Tue Jun 30, 2020 03:00
Key points The locus coeruleus (LC) contains noradrenergic (NA) neurons that respond to novel stimuli in the environment with phasic activation to initiate an orienting response; phasic LC activation is also triggered by stimuli, representing the outcome of task‐related decision processes, to facilitate ensuing behaviours and help optimize task performance. Here, we report that LC‐NA neurons exhibit bursts of action potentials in vitro resembling phasic LC activation in vivo, and the activity...
Mon Jun 29, 2020 16:31
Mon Jun 29, 2020 16:31
Key points We simulate the unitary local field potential (uLFP) generated in the hippocampus CA3, using morphologically detailed models. The model suggests that cancelling effects between apical and basal dendritic synapses explain the low amplitude of excitatory uLFPs. Inhibitory synapses around the soma do not cancel and could explain the high‐amplitude inhibitory uLFPs. These results suggest that somatic inhibition constitute a strong component of LFPs, which may explain a number of experimental...
Mon Jun 29, 2020 16:29
Active pulmonary tuberculosis involving the lung parenchyma is typically seen on CT as consolidation, centrilobular nodules with tree-in-bud branching, cavitating lesions, and miliary nodules. However, some atypical CT patterns of granulomatous disease including tuberculosis have been recently described, namely, clusters of nodules without confluence or with confluence. We present a case of a patient who was found to have nonconfluent clusters of micronodules in the right lung with negative sputum...
Tue Jun 30, 2020 10:50
OTU deubiquitinase 5 (OTUD5), as a member of the ovarian tumor protease (OTU) family, was previously reported to play important roles in DNA repair and immunity. However, little is known about its function in tumors. Cervical cancer is a malignant tumor that seriously endangers the lives of women. Here, we found that low expression of OTUD5 in cervical cancer is associated with poor prognosis. Its expression is associated with tumor stage, metastatic nodes and tumor subtypes such as those related...
Tue Jun 30, 2020 03:00
Gills are important organs for aquatic invertebrates because they harbor chemosynthetic bacteria, which fix inorganic carbon and/or nitrogen and provide their hosts with organic compounds. Nevertheless, in contrast to the intensive researches related to the gut microbiota, much is still needed to further understand the microbiota within the gills of invertebrates. Using abalones as a model, we investigated the community structure of microbes associated with the gills of these invertebrates using...
Tue Jun 30, 2020 03:00
Background Kidney renal clear cell carcinoma (KIRC) affects the genitourinary system. Although treatment of KIRC in early stages can be highly successful, this type of cancer is difficult to detect until later stages of disease that are less easily treatable. Previous studies have focused on tumor cells, but have ignored the contributions of the tumor microenvironment. Methods We analyzed KIRC gene expression data from The Cancer Genome Atlas with the ESTIMATE algorithm to identify differentially...
Tue Jun 30, 2020 03:00
Marine predators adapt their hunting techniques to locate and capture prey in response to their surrounding environment. However, little is known about how certain strategies influence foraging success and efficiency. Due to the miniaturisation of animal tracking technologies, a single individual can be equipped with multiple data loggers to obtain multi-scale tracking information. With the addition of animal-borne video data loggers, it is possible to provide context-specific information for movement...
Tue Jun 30, 2020 03:00
Background The role of methane in global warming has become paramount to the environment and the human society, especially in the past few decades. Methane cycling microbial communities play an important role in the global methane cycle, which is why the characterization of these communities is critical to understand and manipulate their behavior. Methanotrophs are a major player in these communities and are able to oxidize methane as their primary carbon source. ...
Tue Jun 30, 2020 03:00
Pleurosternon bullockii is a turtle from the Early Cretaceous of Europe known from numerous postcranial remains. Only one skull has so far been referred to the species. Pleurosternon bullockii belongs to a group of turtles called pleurosternids, which is thought to include several poorly known taxa from the Late Jurassic and Early Cretaceous of Europe and North America. Pleurosternids and baenids, a group of North American turtles that lived from the Late Cretaceous to the Eocene, define a clade...
Tue Jun 30, 2020 03:00
Extant and extinct reptiles exhibit numerous combinations of tooth implantation and attachment. Tooth implantation ranges from those possessing roots and lying within a socket (thecodonty), to teeth lying against the lingual wall of the jawbone (pleurodonty), to teeth without roots or sockets that are attached to the apex of the marginal jawbones (acrodonty). Attachment may be ligamentous (gomphosis) or via fusion (ankylosis). Generally speaking, adaptative reasonings are proposed as an underlying...
Tue Jun 30, 2020 03:00
Oligomers to the aid of ITH : A way to directly synthesize aluminosilicate ITH (Al‐ITH) zeolite using a cationic oligomer as an organic template is presented: The strong complexation ability with aluminum species is a key factor for the successful preparation. Abstract There are a large number of zeolites, such as ITH, that cannot be prepared in the aluminosilicate form. Now, the successful synthesis of aluminosilicate ITH zeolite using a simple cationic oligomer as an organic template...
Tue Jun 30, 2020 11:36
A palladium catalyst and a chiral phosphoric acid act synergistically to induce enantiocontrol in intramolecular allylic substitution reactions, and statistical modeling has identified multiple noncovalent interactions. These mechanistic studies led to an expansion of synthetic scope to the formation of challenging tertiary ether stereocenters. Abstract The mode of asymmetric induction in an enantioselective intramolecular allylic substitution reaction catalyzed by a combination of palladium...
Tue Jun 30, 2020 11:36
Fighting influenza : Through the combination of flexibility and multivalent binding, a sialylated nanogel is able to bind and adapt onto the influenza A virus surface. The resulting flexible nanogel efficiently blocks the virus binding onto the cell and inhibits infection at low pM concentrations. Abstract Flexible multivalent 3D nanosystems that can deform and adapt onto the virus surface via specific ligand–receptor multivalent interactions can efficiently block virus adhesion onto the...
Tue Jun 30, 2020 11:36
Break it down again : Certain bacteria can break down N ,N ‐dimethyl formamide (DMF) through the action of a dimethylformamidase (DMFase). The structure and mechanism of a DMFase from a bacterium of the genus Paracoccus are presented. The enzyme comprises a multimeric α2β2 or (α2β2)2 complex, and the active site consists of FeIII coordinated by two Tyr side‐chain phenolates and one carboxylate from Glu in an unusual square pyramidal geometry. Abstract N,N‐dimethyl formamide (DMF) is an...
Tue Jun 30, 2020 11:36
Conformational design through purposeful control of the conformation population of molecules significantly facilitates the construction of both stereochemistry and rings in the total synthesis of complex natural products. This Minireview summarizes the progress of this field in the last two decades and especially emphasizes the critical role of implementing a C−H functionalization strategy in natural‐product synthesis. Abstract Conformation is one of the most fundamental concepts in organic...
Tue Jun 30, 2020 11:36
It takes two : CuH/Pd‐catalyzed enantioselective hydroarylation of 1,1‐disubstituted alkenes proceeds with anti‐Markovnikov regioselectivity under mild conditions to access β‐stereogenic arenes. A wide range of aryl bromides, including several heterocycle‐containing substrates, can be used with good efficiency and enantioselectivity. Various 1,1‐disubstituted alkenes were also examined. Abstract Arenes with β‐stereogenic centers are important substructures in pharmaceuticals and natural...
Tue Jun 30, 2020 11:36
PDT with a twist : The intersystem crossing (ISC) mechanism of a heavy atom‐free helical bodipy derivative was elucidated. Due to the intense absorption at long wavelengths (ϵ =1.76×105 m −1 cm−1 at 630 nm), satisfactory triplet quantum yield (ΦT=52 %), and long‐lived triplet state (τ T=492 μs), a record low‐dose photodynamic therapy (PDT)‐augmented immunotherapy was achieved. Abstract Intersystem crossing (ISC) of triplet photosensitizers is a vital process for fundamental photochemistry...
Tue Jun 30, 2020 11:36
A new route to the classical ylide Ph3As=CH2 resolves previous difficulties in its synthesis and isolation. Its structural authentication, 45 years after it was first made, confirms that the ylide is pyramidal not planar, and it enables the synthesis of a uranium–arsonium–carbene, the first structurally characterised example of an arsonium–carbene complex of any metal. Abstract Treatment of [Ph3EMe][I] with [Na{N(SiMe3)2}] affords the ylides [Ph3E=CH2] (E=As, 1As ; P, 1P ). For 1As this...
Tue Jun 30, 2020 11:36
A high‐entropy oxide material with mesoporous structure is prepared by an anchoring and merging process. It exhibits ultra‐high catalytic activity for the oxidation of benzyl alcohol. Benzoic acid or benzaldehyde can be selectively optimized as the main product by rational regulating the catalysis parameters. Abstract The development of noble‐metal‐free heterogeneous catalysts is promising for selective oxidation of aromatic alcohols; however, the relatively low conversion of non‐noble...
Tue Jun 30, 2020 11:36
The evolution of transition metals was studied in Li‐ and Mn‐rich layered cathode materials during long‐term cycling. The results reveal that the conversion of layer to spinel phase shows partial reversibility in each cycle on a sub‐nanometer scale depending on the particle size. Abstract Li‐ and Mn‐rich layered oxides are among the most promising cathode materials for Li‐ion batteries with high theoretical energy density. Its practical application is, however, hampered by the capacity...
Tue Jun 30, 2020 11:36
Hexagonal, exceptional : In a graphene liquid cell, beryllium oxide can crystallize in a rare sp2‐coordinated, hexagonal BeO polymorph. The thickness of the crystals produced this way is beyond the thermodynamic ultra‐thin limit above which the wurtzite phase is energetically more favorable. Calculations show that the energy barrier of the phase transition is responsible for the observed occurrence of hexagonal layers. Abstract Using high‐resolution transmission electron microscopy and...
Tue Jun 30, 2020 11:36
Ultramicropore control of molecular sieving in two forms of calcium trimesate leads to the first non‐membrane solid that serves as a molecular sieve for H2 over slightly larger gas molecules, including CO2 and N2. Abstract The high energy footprint of commodity gas purification and increasing demand for gases require new approaches to gas separation. Kinetic separation of gas mixtures through molecular sieving can enable separation by molecular size or shape exclusion. Physisorbents must...
Mon Jun 29, 2020 22:00
Mon Jun 29, 2020 21:00
Fluorescent probes that can discriminate enantiomers of amino acids in either organic media or aqueous solution are discussed. This article focuses on the recent progresses in the study of three classes of probes including those made of cyclodextrins, 1,1’‐binaphthyls and nanomaterials and attempts to use these studies to illustrate the design strategies, applications and limitations in this area. These probes are potentially useful for rapid analysis of the reactions for asymmetric amino acid...
Mon Jun 29, 2020 20:48
A Cu‐catalyzed enantioselective hydroamination of α,β‐unsaturated carbonyl compounds for the synthesis of β ‐amino acid derivatives was achieved through ligand‐controlled reversal of the hydrocupration regioselectivity. While the hydrocupration of α,β‐unsaturated carbonyl compounds to form α‐cuprated species has been extensively investigated, we report herein that, in the presence of an appropriate ancillary chiral ligand, the alternative regiochemistry can be observed for cinnamic acid derivatives,...
Mon Jun 29, 2020 19:55
Solution‐state aggregation of conjugated polymers is critical in determining their solid‐state microstructures and optoelectronic performance. However, controlling the solution‐state aggregation of conjugated polymers for producing specific microstructures remains challenging. Herein, a practical approach is developed to finely tune the solid‐state microstructures through temperature‐controlled solution‐state aggregation and polymer crystallization. High temperature generates significant conformation...
Mon Jun 29, 2020 19:55
The visualization of temporal and spatial changes in the intracellular environment has great significance for chemistry and bioscience research. Mass spectrometry imaging (MSI) is playing an increasingly important role in this field because of its unique advantages, such as being label‐free and high throughput, yet it remains a great challenge for laser‐based techniques due to limited lateral resolution. Here, we develop a simple, reliable and economic nanoscale MSI approach by introducing desorption...
Mon Jun 29, 2020 19:38
Catalytic methanol synthesis is one of the major processes in the chemical industry and may grow in importance, as methanol produced from CO2 and sustainably derived H2 is envisioned to play an important role as energy carrier in a future low CO2 emission society. However, despite the widespread use, the reaction mechanism and the nature of the active sites are not fully understood. Here we report that methanol synthesis at commercially applied conditions using the industrial Cu/ZnO/Al2O3 catalyst...
Mon Jun 29, 2020 18:54
Mon Jun 29, 2020 18:23
Described in this paper are the synthesis and structure of novel and edge‐functionalized zigzag hydrocarbon belts. A stepwise fjord‐stitching strategy featuring repetitive intramolecular acylation reactions of a resorcin[4]arene derivative as the key steps afforded a biscarbonyl‐functionalized octahydrobelt[8]arene product. Facile ketone reduction with NaBH4 and nucleophilic addition reaction with n‐butyllithium produced secondary and tertiary alcohol‐containing molecular belts, respectively. Selective...
Mon Jun 29, 2020 17:34
Water‐soluble polymers for HER : As inspired by enzymes, three water‐soluble polymers with appending Co porphyrins and different side‐chain groups are designed. These catalysts show high activity and stability for electro‐ and photocatalytic HER in neutral aqueous solutions. With the same Co porphyrin, the activity can be fine‐tuned by using different side‐chain groups. Abstract Molecular design to improve catalyst performance is significant but challenging. In enzymes, residue groups that...
Mon Jun 29, 2020 17:04
Despite the clinical success of Pt anti‐cancer drugs, metal‐based drugs are slow to enter the clinic, due to their coordination chemistry and typically short lifetimes in biological environments. We propose that this can be turned into advantage for direct injections into the tumor, which will allow use of highly cytotoxic drugs. The release of their less toxic decomposition products into the blood will lead to reduced systemic toxicity and can even have beneficial effect, such as the neurostimulatory...
Mon Jun 29, 2020 16:55
Sulfide solid electrolytes are promising inorganic solid electrolytes for all‐solid‐state batteries. Despite their high ionic conductivity and desirable mechanical properties, many known sulfide solid electrolytes exhibit poor air stability. The spontaneous hydrolysis reactions of sulfides with moisture in air lead to toxic hydrogen sulfide release and materials degradation, hindering large‐scale manufacturing and applications of sulfide‐based solid‐state batteries. In this work, we systematically...
Mon Jun 29, 2020 15:25
Double helices and other hierarchical structures of elemental phosphorus can be built from the simple P8 cage. Machine‐learning‐driven and fragment‐based searches enable a rapid exploration of structural space, and dispersion‐corrected DFT computations reveal the resulting structures to be more stable than white phosphorus. Abstract The discovery of materials is increasingly guided by quantum‐mechanical crystal‐structure prediction, but the structural complexity in bulk and nanoscale materials...
Mon Jun 29, 2020 15:23
Handy hybrids : A material based on gold nanoparticles stabilized by organic–inorganic hybrid polyoxometalates is described (see picture). The new nanomaterial exhibits unprecedented stability and photoactivity under visible light and can be reversibly reduced and oxidized at electrode surfaces, making it very promising for future photonic and electrochemical systems. Abstract We report the design and preparation of multifunctional hybrid nanomaterials through the stabilization of gold...
Mon Jun 29, 2020 15:22
The absolute configuration of difficult‐to‐crystallize small molecules can be obtained by rapid thermal co‐crystallization with TEO, a tetraaryladamantane octaether, and X‐ray crystallography. As little as 3–5 mg of analyte can produce both NMR and diffraction data within 48 hours. Abstract The most reliable method to determine the absolute configuration of chiral molecules is X‐ray crystallography, but small molecules can be difficult to crystallize. We report rapid co‐crystallization...
Mon Jun 29, 2020 15:21
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