Otolaryngologic Clinics of North America
- Partnership with Interventional PulmonologistVia the emergence of new bronchoscopic technologies and techniques, there is enormous growth in the number of procedures being performed in nonoperating room settings. This, coupled with a greater focus from the Centers for Medicare and Medicaid Services for mandated anesthesiology oversight of procedural sedation for bronchoscopy by the pulmonologists has led to a more frequent working partnership between interventional pulmonologists and anesth
- Anesthesia and Chronic Pain ManagementThe reasons for development of chronic pain are poorly understood. Chronic postoperative pain is linked to severe acute postoperative pain. Head and neck pain is often a complex phenomenon that requires meticulous diagnosis and treatment. Institution of early multimodal analgesic regimens by multidisciplinary teams may attenuate chronic pain formation and propagation in the otolaryngologic patient.
- The Difficult AirwayAirway management is a cornerstone of anesthetic practice, and difficulty with airway management has potentially grave implications—failure to secure a patent airway can result in hypoxic brain injury or death in a matter of minutes. The difficult airway in otolaryngologic surgery requires careful planning and close communication between the anesthesiologist and ENT or head and neck surgeon. Knowledge of predictive factors and a detailed preopera
Medgadget
- Apps for Healthcare Monitoring: Interview with Artem Petrov, CEO of ReinventlyReinvently, a mobile app development company based in Palo Alto, California, has created a number of healthcare apps, including those which collect, collate, and display data from wearable medical devices. The combination of a wearable device and a mobile app allows clinicians to monitor their patients in real-time and identify issues before they become a problem. This approach is becoming increasingly popular, but in many cases, wearable
- Implantable Nanolasers for Tissue Imaging, NeurotherapyA variety of imaging techniques and technologies, such as optogenetics, could benefit from devices that can emit visible laser light from inside tissues. Conventional lasers are too large, while nanolasers tend to be inefficient, heating up too much, and typically require damaging ultraviolet light to power them. Now, researchers at Northwestern and Columbia Universities have developed a nanolaser that can be powered by deep-penetrating a
- First Portable Brain-Computer Interface to Control Wheelchairs, TVs, ComputersBrain-computer interfaces have the potential to give severely disabled people the ability to easily control their wheelchairs, televisions, and other devices. Existing technologies suffer from a number of limitations, though, making them impractical for real-world applications. One is that non-invasive brain wave monitoring currently requires large and uncomfortable electroencephalography caps with wet electrodes, wires, and associated adh
Angewandte Chemie International Edition
- Expedient Synthesis of Core Disaccharide Building Blocks from Natural Polysaccharides for Heparan Sulfate Oligosaccharide AssemblyThe complex sulfation motifs of heparan sulfate glycosaminoglycans (HS GAGs) play critical roles in many important biological processes. However, an understanding of their specific functions has been hampered by an inability to synthesize large numbers of diverse, yet defined, HS structures. Here, we describe a new approach to access the four core disaccharides required for HS/heparin oligosaccharide assembly from natural polysaccharides. The use
- Autonomous discovery in the chemical sciences part I: ProgressThis two‐part review examines how automation has contributed to different aspects of discovery in the chemical sciences. In this first part, we describe a classification for discoveries of physical matter (molecules, materials, devices), processes, and models and how they are unified as search problems. We then introduce a set of questions and considerations relevant to assessing the extent of autonomy. Finally, we describe many case studies of d
- Crystalline Divinyldiarsene Radical Cations and DicationsThe divinyldiarsene radical cations [{(NHC)C(Ph)}As]2(GaCl4) (NHC = IPr: C{(NDipp)CH}2 3; SIPr: C{(NDipp)CH2}2 4; Dipp = 2,6‐iPr2C6H3) and dications [{(NHC)C(Ph)}As]2(GaCl4)2 (NHC = IPr 5; SIPr 6) are readily accessible as crystalline solids on sequential one‐electron oxidation of the corresponding divinyldiarsenes [{(NHC)C(Ph)}As]2 (NHC = IPr 1; SIPr 2) with GaCl3. Compounds 3‐6 have been characterized by X‐ray diffraction, cyclic voltammetry,
- Autonomous discovery in the chemical sciences part II: OutlookThis two‐part review examines how automation has contributed to different aspects of discovery in the chemical sciences. In this second part, we reflect on a selection of exemplary studies. It is increasingly important to articulate what the role of automation and computation has been in the scientific process and how that has or has not accelerated discovery. One can argue that even the best automated systems have yet to "discover" despite being
- Atroposelective arene formation via carbene‐catalyzed formal [4+2] cycloadditionAtroposelective arene formation is an efficient method to build axially chiral molecules with multi‐substituted arenes. Here we report an organocatalyzed atroposelective arene formation reaction via N‐heterocyclic‐carbene catalyzed formal [4+2] cycloaddition of conjugated dienals andα‐aryl ketones. This study expands the synthetic potential of NHC organocatalysis and provides a competitive pathway for the synthesis of axially chiral ligands, cata
- Asymmetric Alkenyl C‐H Functionalization by CpxRhIII forms 2H‐Pyrrol‐2‐ones by [4+1]‐Annulation of Acryl Amides and AllenesAn efficient CpxRhIII‐catalyzed enantioselective alkenyl C‐H functionalization/[4+1] annulation of acryl amides and allenes is reported. The described transformation provides straightforward access to enantioenriched α,β‐unsaturated‐γ‐lactams bearing a quaternary stereocenter. The reaction operates under mild conditions, displays a broad functional group tolerance and provides 2H‐pyrrol‐2‐ones in excellent selectivity of up to 97:3 er. Such scaff
- Covalent Organic Framework (COF‐1) at High PressureCOF‐1 has a structure similar to graphite with rigid 2D layers composed by benzene and B3O3 rings and weak van der Waals bonding between the layers. The as‐synthesized COF‐1 structure contains pores occupied by solvent molecules. High surface area empty‐pore structure is obtained after vacuum annealing. High pressure XRD and Raman experiments with mesitylene filled (COF‐1‐M) and empty pore COF‐1 demonstrate partial amorphization and collapse of t
- Self‐Stabilized Amorphous Organic Materials with Room‐Temperature PhosphorescenceWarming glow: A strategy for obtaining ultra‐stable organic materials with room‐temperature phosphorescence (RTP) without crystallization is presented. The RTP lifetime was 0.16 s, while the intensity increased by 21.5‐fold. The excellent permeability of the amorphous RTP system allowed its application to vapor detection. Abstract The stability of pure organic room‐temperature phosphorescent (RTP) materials in air has been a research hotspo
- Entropically Favoured Assembly of Pyrazine‐Based Helical Fibers into Superstructures: Achiral/ Chiral Guest‐Induced Chirality TransformationTwist and shout: A pyrazine derivative undergoes a helical transformation in aqueous media with l‐alanine as a chiral handle. The generation of helical fibers in aqueous media, the helical‐to‐coiled‐superhelix transition in the presence of achiral guests (Ni2+ ions), and the transition of the supercoiled helix to a superhelix in the presence of chiral guests (d/l‐histidine) are entropically driven processes. Abstract The development of synt
- A Reversible Electron Relay to Exclude Sacrificial Electron Donors in the Photocatalytic Oxygen Atom Transfer Reaction with O2 in WaterThe evil necessity of sacrificial electron donors (SEDs) in the photoactivation of O2 can be ousted by the use of a reversible electron acceptor (methylviologen). It intervenes as an electron carrier from the excited photosensitizer to reduce both O2 and an iron(III) catalyst to form a reactive FeIII–peroxo species for oxygen atom transfer reactions. Oxidation of an organic substrate closes the photocatalytic cycle. Abstract Using light ene
- Inhibiting VOPO4⋅x H2O Decomposition and Dissolution in Rechargeable Aqueous Zinc Batteries to Promote Voltage and Capacity StabilitiesThe VOPO4⋅x H2O cathode undergoes decomposition and dissolution in rechargeable aqueous Zn batteries. A 13 m ZnCl2/0.8 m H3PO4 aqueous electrolyte is designed to inhibit its degradation, allowing stable capacity and voltage retentions over cycling. Sequential H+ and Zn2+ intercalations into the structure deliver a high capacity of 170 mAh g−1. Abstract VOPO4⋅x H2O has been proposed as a cathode for rechargeable aqueous zinc batteries. H
- 1,2‐Dithienyldicyanoethene‐Based, Visible‐Light‐Driven, Chiral Fluorescent Molecular Switch: Rewritable Multimodal Photonic DevicesWrite away: A distinct 1,2‐dithienyldicyanoethene‐based light‐driven chiral fluorescent molecular switch that exhibits reversible trans to cis photoisomerization in both isotropic solvents and a liquid crystal medium, upon visible‐light irradiation, is accomplished. Optically rewritable multimodal liquid crystal photonic devices based on this switch are demonstrated. CPL=circularly polarized luminescence, CPR=circularly polarized reflection.
- The Parent Diarsene HAs=AsH as Side‐on Bound Ligand in an Iron Carbonyl ComplexThe elusive HAs=AsH, the heavy analogue of ethylene, is side‐on coordinated by a 3d transition metal complex without using kinetic stabilisation. By methanolysis of [{Fe(CO)4}As(SiMe3)3], the complex [{Fe(CO)4}{η2‐As2H2}] was synthesized. DFT calculations show that the bonding mode can be best described by the Dewar–Chatt–Duncanson model. Subsequent reactivity studies reveal that it reacts as an AsH transfer reagent. Abstract The terminal d
- Safe, Low‐Cost, Fast‐Kinetics and Low‐Strain Inorganic‐Open‐Framework Anode for Potassium‐Ion BatteriesInorganic‐open‐framework (IOF) KTiOPO4 allows reversible K+ intercalation into its large interstitial vacancies under a stepwise biphasic and solid solution reaction mechanism. Its fast K+‐transport kinetics (≈10 times higher than those of Na superionic conductors), low‐strain feature (a cell volume change even smaller than that of Li+‐insertion in graphite) and high stability highlight IOFs as a promising new anode category for K‐ion batteries.
- Total Synthesis of (−)‐Himeradine AThe complex alkaloid (−)‐Himeradine A was prepared from 2‐bromo‐4‐methylpyridine in 17 steps for the longest linear sequence. Key transformations include a diastereoselective piperidine hydrogenation, classical salt resolution, diastereoselective Overman rearrangement, B‐alkyl Suzuki coupling, and a final Mannich cascade that formed 5 bonds and 4 rings in one reaction flask. Abstract (−)‐Himeradine A is a complex lycopodium alkaloid with se
- Polymer Composite Membrane with Penetrating ZIF‐7 Sheets Displays High Hydrogen PermselectivityThe separation performance of the ZIF‐7@polyimide (PI) mixed matrix membrane (MMM) is determined by the embedded ZIF‐7 sheets rather than by the polyimide matrix. Every ZIF‐7 sheet penetrates both surfaces of the PI matrix such that the ZIF‐7 channels provide the dominant pathway for gas permeation. The ZIF‐7@polyimide MMM is effective at separating H2 from larger gas molecules. Abstract Oriented and penetrating molecular sieving membranes
- Three Mechanisms in One Material: Uranium Capture by a Polyoxometalate–Organic Framework through Combined Complexation, Chemical Reduction, and Photocatalytic ReductionStuck on U: Uranium capture by a polyoxometalate–organic framework is possible through three different mechanism, these are complexation, chemical reduction, and photocatalytic reduction. The material features a unique 2D+2D→3D polycatenation structure, resulting in excellent stability toward hydrolysis and ionization irradiation. Abstract The design and synthesis of uranium sorbent materials with high uptake efficiency, capacity and select
- Palladium Catalysis for Aerobic Oxidation Systems Using Robust Metal–Organic FrameworkAll‐in‐one: Immobilizing PdII and CuII species into a robust metal–organic framework (MOF) facilitates the Pd catalysis for an aerobic oxidation system, a desulfitative oxidative coupling reaction, with high efficiency, low catalyst loading, and reusability. These results demonstrate the ability to merge a PdII catalyst, a ligand, and an electron‐transfer mediator into a single MOF to boost activity in an efficient and sustainable manner. Ab
- Biomimetic Synthesis of Meroterpenoids by Dearomatization‐Driven PolycyclizationRegioselective dearomatization of 3,5‐dimethylorsellinic acid (DMOA) provides rapid access to a key dearomatized intermediate in the biosynthetic pathway of DMOA‐derived meroterpenoids. This intermediate undergoes polycyclization under Lewis acid mediation to provide meroterpenoid scaffolds. Several structurally novel meroterpenoids were obtained by termination via either C‐ or O‐cyclization. Abstract A biomimetic route to farnesyl pyrophos
- A Hydrogen‐Bonded Organic Framework (HOF) with Type IV NH3 Adsorption BehaviorEasy come, easy go: A hydrogen‐bonded organic framework (HOF) can interact with NH3 to give a type IV ammonia isotherm. This characteristic is responsible for high working capacity and facile release of NH3 under mild conditions. Abstract An S‐shaped gas isotherm pattern displays high working capacity in pressure‐swing adsorption cycle, as established for CO2, CH4, acetylene, and CO. However, to our knowledge, this type of adsorption behavi
- Economical, Green, and Safe Route Towards Substituted Lactones by Anodic Generation of Oxycarbonyl RadicalsClean electricity: A new electrochemical method generates oxycarbonyl radicals under mild and green conditions from readily available hemioxalate salts. Mono‐ and multi‐functionalised γ‐butyrolactones were synthesised through exo‐cyclisation of these oxycarbonyl radicals with an alkene, followed by the sp3–sp3 capture of the newly formed carbon‐centred radical. Abstract A new electrochemical methodology has been developed for the generation
- The Simplest but Isolable Alkynyl Isocyanate HC≡CNCOAlkynyl isocyanates have been postulated as highly reactive intermediates in synthetic chemistry. Herein, we describe a first time isolation of the parent molecule HC ≡ CNCO. In sharp contrast to the previously reported short lifetime (ca. 15 s) at room temperature, we found that HC ≡ CNCO has a lifetime of 55 h in the gas phase (2 mbar, 300 K) with a melting point of –79.5 ° C and vaporization enthalpy (Δ H vap ) of 23.1(1) kJ mol –1 . In
- Direct Conversion of Methane with Carbon Dioxide Mediated by RhVO3− Cluster AnionsDirect conversion of methane with carbon dioxide to value‐added chemicals is attractive but extremely challenging because of the thermodynamic stability and kinetic inertness of both molecules. Herein, the first dinuclear cluster species, RhVO 3 – , has been designed to mediate the co‐conversion of CH 4 and CO 2 to oxygenated products, CH 3 OH and CH 2 O, in the temperature range of 393‐600 K. The resulting cluster ions RhVO 3 CO –
- Activation and Characterization of a Cryptic Gene Cluster Reveal Two Series of Aromatic Polyketides Biosynthesized by Divergent tic Tailoring PathwaysOne biosynthetic gene cluster (BGC) usually governs the biosynthesis of a series of compounds exhibiting the same or similar molecular scaffold. Here, we report a multiplex activation strategy to awaken a cryptic BGC associated with the tetracycline polyketides resulting in the discovery of skeleton‐different compounds. By constitutively expressing a positive regulator gene in tandem mode, the single BGC directed the biosynthesis of eight aromati
- Stabilization of Classical [B2H5]‐: Structure and Bonding of [(Cp*Ta)2(B2H5)(µ‐H)L2] (Cp* = η5‐C5Me5; L = SCH2S)The room temperature reaction of [Cp*TaCl 4 ] with LiBH 4 .THF followed by addition of S 2 CPPh 3 results in pentahydridodiborate species [(Cp*Ta) 2 (µ,η 2 :η 2 ‐B 2 H 5 )(μ‐H)(κ 2 ,µ‐S 2 CH 2 ) 2 ] ( 1 ), a classical [B 2 H 5 ] ‐ ion stabilized by the binuclear tantalum template. Theoretical studies and bonding analysis established that the unusual stability of [B 2 H 5 ] ‐ in 1 is mainly due to the stab
- Multi‐Resonance Induced Thermally Activated Delayed Fluorophores for Narrowband Green OLEDsHigh‐color purity emissions with small a full‐width at half‐maximum (FWHM) are ongoing pursuit for high‐resolution displays. Though the flourishment of narrow‐band emissive materials with multi‐resonance induced thermally activated delayed fluorescence (MR‐TADF) in blue region, such materials haven’t validated their potential in other color regions. By amplifying the influence of skeleton and peripheral units, a series of highly efficient green‐e
- Polymerizations Mediated by Well‐defined Rhodium ComplexesThis minireview details the current state‐of‐the‐art relating to (co)polymerizations mediated by well‐defined Rh(I)‐ethynyl, vinyl and aryl complexes. In particular we focus on Rh(I) species suitable for the (controlled) (co)polymerization of phenylacetylenes, arylisocyanides and propargyl esters and amides.
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