Chanli1584

Single-molecule conductance of a B-N substituted phenanthrene derivative and its isoelectronic C═C counterpart was investigated by the scanning tunneling microscopy break junction (STM-BJ) technique. The incorporation of the B-N motif results in a better single-molecule conductivity than the C═C analogue. Furthermore, the Lewis acid-base reaction between F- and the B atom of the B-N motif leads to a decrease of the conductance of the BN derivative, which can be understood due to the shifting of the energy positions of the LUMO, as revealed by quantum transport calculations, even though the HOMO-LUMO gap decreases in the B-F Lewis acid-base. These findings provide insights for modulating electron transport properties by isoelectronic structure design. The B-N isoelectronic substituted structure could be a feasible way to design single-molecule devices such as switches and chemical sensors.Herein, a nanowelding technique is adopted to fabricate three-dimensional layer-by-layer Pd-containing nanocomposite structures with special properties. Nanowires fabricated from noble metals (Pd, Pt, Au, and Ag) were used to prepare Pd-Pd nanostructures and Pd-Au, Pd-Pt, Pd-Ag, and Pd-Pt-Au nanocomposite structures by controlling the welding temperature. The recrystallization behavior of the welded composite materials was observed and analyzed. In addition, their excellent mechanical and electrical properties were confirmed by performing 10,000 bending test cycles and measuring the resistances. Finally, flexible and wearable nanoheaters and gas sensors were fabricated using our proposed method. In comparison with conventional techniques, our proposed method can not only easily achieve sensors with a large surface area and flexibility but also improve their performance through the addition of catalyst metals. A gas sensor fabricated using the Pd-Au nanocomposites demonstrated 3.9-fold and 1.1-fold faster H2 recovery and response, respectively, than a pure Pd-Pd gas sensor device. Moreover, the Pd-Ag nanocomposite exhibited a high sensitivity of 5.5% (better than that of other fabricated gas sensors) for 1.6% H2 concentration. Therefore, we believe that the fabricated nanocomposites appear promising for wide applications in wearable gas sensors, flexible optical devices, and flexible catalytic devices.The structural transformation from symmetric cumulene to broken-symmetry polyyne within a one-dimensional (1-D) atomic carbon chain is a signature of Peierls distortion. Direct observation of such a structural transformation with single-bond resolution is, however, still challenging. Herein, we design a molecule with a cumulene moiety (Br2C═C═C═CBr2) and employ STM tip manipulation to achieve the molecular skeleton rearrangement from a cumulene to a diyne moiety (Br-C≡C-C≡C-Br). Furthermore, by an on-surface reaction strategy, thermally induced entire debromination (C═C═C═C) leads to the formation of a 1-D organometallic polyyne (-C≡C-C≡C-Au-) with a semiconducting characteristic, which implies that a Peierls-like transition may occur in a rationally designed molecular system with limited length.Most bromodomain inhibitors mimic the interactions of the natural acetylated lysine (KAc) histone substrate through key interactions with conserved asparagine and tyrosine residues within the binding pocket. Herein we report the optimization of a series of phenyl sulfonamides that exhibit a novel mode of binding to non-bromodomain and extra terminal domain (non-BET) bromodomains through displacement of a normally conserved network of four water molecules. Starting from an initial hit molecule, we report its divergent optimization toward the ATPase family AAA domain containing 2 (ATAD2) and cat eye syndrome chromosome region, candidate 2 (CECR2) domains. This work concludes with the identification of (R)-55 (GSK232), a highly selective, cellularly penetrant CECR2 inhibitor with excellent physicochemical properties.Since the groundbreaking discovery in 2018 that the synthesis of a bottleable nucleophilic aluminyl anion is feasible, a handful of derivatives have been developed to date, which are, however, limited to diamino- and dialkyl-substituted species. Herein, we report the synthesis of a cyclic (alkyl)(amino)aluminyl anion based on a five-membered framework. The dicoordinate aluminum center features both a lone pair of electrons and an unoccupied 3p orbital, thus genuinely making it isoelectronic with carbenes. We show the bond formation and bond activation at the Al sphere thus, not only does it undergo electron redistribution with borane to furnish a heteroatomic group 13 ring exhibiting a σ-aromatic nature concomitant with a three-center two-electron AlB2 bond but also the ambiphilic nature allows for oxidative addition of Si-H, N-H, and even C-C bonds at the aluminum center.A thermodynamically stable terpyridine-dicarboxylate based emissive Eu(III) probe, [Eu(OH-TPDC)] (1), was designed as a time-resolved "turn-on" luminescent probe for the selective sensing of diethyl chlorophosphate (DCP), a G-series nerve agent simulant through modulation of sensitization of 5D0 → 7FJ transitions from Eu(III) via quenching of nonradiative vibrational energy transfer.The simultaneous imaging of magnetic fields and temperature (MT) is important in a range of applications, including studies of carrier transport, and semiconductor device characterization. Techniques exist for separately measuring temperature (e.g., infrared (IR) microscopy, micro-Raman spectroscopy, and thermo-reflectance microscopy) and magnetic fields (e.g., scanning probe magnetic force microscopy and superconducting quantum interference devices). However, these techniques cannot measure magnetic fields and temperature simultaneously. Here, we use the exceptional temperature and magnetic field sensitivity of nitrogen vacancy (NV) spins in conformally-coated nanodiamonds to realize simultaneous wide-field MT imaging at the device level. Our "quantum conformally-attached thermo-magnetic" (Q-CAT) imaging enables (i) wide-field, high-frame-rate imaging (100 - 1000 Hz); (ii) high sensitivity; and (iii) compatibility with standard microscopes. We apply this technique to study the industrially important problem of characterizing multifinger gallium nitride high-electron-mobility transistors (GaN HEMTs). We spatially and temporally resolve the electric current distribution and resulting temperature rise, elucidating functional device behavior at the microscopic level. The general applicability of Q-CAT imaging serves as an important tool for understanding complex MT phenomena in material science, device physics, and related fields.Seawater desalination via solar energy has potential to alleviate freshwater scarcity. However, problems including insufficient air-water interface, large heat loss, and potential ecological impact have restricted its practical viability. Here, a novel wood-derived indirect-contact (hanging) photothermal evaporation system was designed. An evaporation rate of 1.351 kg·m-2·h-1 with efficiency up to 90.89% under one sun illumination (1 kW·m-2) was achieved, which is the highest record to the best of our knowledge. More importantly, a series of simulations and numerical modeling were carried out to analyze the main factors affecting seawater collection and evaporation, and the synergetic mechanisms of oriented seawater collection, photothermal thermogenesis, and natural convection were elucidated. Taken together, this study provides a new wood-derived hanging seawater desalination system with superior mechanical strength, good repeatability, great ecological security, and excellent thermal stability. The corresponding mechanisms of the whole process are shown, and the seawater evaporation efficiency approaching the real demand is maximized.BACKGROUND Children with neurodegenerative diseases progressively lose skills and develop somatic and psychiatric symptoms. Obsessive-compulsive disorder (OCD) may occur, a disorder for which effective medical and psychological treatments are available. However, whether these treatments are useful for children with neurodegenerative disease is unknown. CASE PRESENTATION A child with an uncommon form of neurodegenerative disease (with loss of sight and incipient cognitive decline) had during the previous year developed time-consuming compulsive behaviours. The child spent much of the day at home (> 8 hours), turning on/off switches, opening/closing doors, repeating after others and so on. A diagnostic assessment concluded that the child fulfilled the criteria for OCD, with predominantly compulsive acts. The child began combined treatment with sertraline and exposure and response prevention therapy (ERP). It was necessary to adapt the ERP to the neurodegenerative disease, with strong parental involvement. After six months the compulsive acts were gone. INTERPRETATION Children with neurodegenerative disease may have a high risk of psychiatric disorders, but the literature is sparse on phenomenology and treatments. The present case study documents that OCD can occur in a child with neurodegenerative disease and that the combined medical and psychological treatments were effective.BACKGROUND COVID-19 can cause a fatal outcome in elderly patients, as this case report illustrates. CASE PRESENTATION An active male in his nineties with a high level of function, despite several severe chronic diseases, was admitted to Oslo University Hospital after two days of fatigue, fever, dyspnoea and dry cough. He scored qSOFA 1 of 3 points due to high respiratory rate, and SIRS 2 of 4 points due to high respiratory rate and fever of 39.4º C. PCR for influenza virus was negative and he received benzylpenicillin for pneumonia. The chest X-ray taken initially showed no lung affection. On day 5 after symptom debut he was tested for COVID-19 which was positive. He had not been travelling to high-risk areas or been exposed to any known confirmed COVID-19 patients. On the same day, a chest CT scan was performed that showed ground-glass opacities. In subsequent days the patient's health rapidly deteriorated. He developed irreversible respiratory failure with hypoxia without hypercapnia despite substantial oxygen support. Chest X-ray taken on disease day 7 showed progression of consolidations. The patient died 9 days after symptom debut. INTERPRETATION This case illustrates a severe course of COVID-19 with fatal outcome. The patient was also one of the earliest admitted with COVID-19 in a Norwegian hospital and marked a new phase of the epidemic, as he had not been travelling to high-risk areas or been exposed to any confirmed COVID-19 patients.BACKGROUND Diffuse large B-cell lymphoma is an aggressive non-Hodgkin lymphoma. The patients are often critically ill with a variety of symptoms, but the disease is potentially curable. CASE PRESENTATION A previously healthy man in his forties was admitted to the local hospital feeling unwell, with dyspnoea, cough, fever and weight loss. The clinical examination was normal. Lactate dehydrogenase and sedimentation rate were elevated. Blood smear and bone marrow biopsy were normal. In the weeks that followed, the patient became critically ill with respiratory failure, exhaustion and continuous fever. Computed tomography (CT) scan revealed diffuse lung infiltrates in addition to hepatosplenomegaly. High levels of ferritin, triglycerides and soluble interleukin-2 receptor were also found. Haemophagocytic lymphohistiocytosis was suspected, and the patient was admitted to the intensive care unit. Biopsies confirmed diffuse large B-cell lymphoma, and treatment was started immediately. INTERPRETATION The clinical manifestations of lymphoma are diverse.