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Supramolecular photosensitisers comprising a ring-shaped Re(i) tetranuclear complex and a Keggin-type heteropolyoxometalate were synthesised. They can photochemically accumulate four electrons and supply them for the photocatalytic CO2 reduction.

Background Due to potentially fatal consequences of missed bacteremia, blood cultures are often overused. While there are several prediction models that can be used to identify patients who truly need blood cultures, physicians often rely on their gestalt. We evaluated the diagnostic performance of physician gestalt for bacteremia in comparison with 2 existing prediction models: Takeshima and Shapiro. Methods The study enrolled consecutive adult patients with suspected infection who were in the process of being admitted to the general medicine department at 2 hospitals between April 2017 and January 2019. Attending physicians provided gestalt regarding risk of bacteremia (0%–100%). Patients with a Results Among 2014 patients, 292 (14.5%) were diagnosed with bacteremia. The safety of physician gestalt and the Takeshima and Shapiro models was 3.7% (95% confidence interval [CI], 2.2% to 5.7%), 6.5% (95% CI, 5.0% to 7.9%), and 10.8% (95% CI, 9.4% to 12.3%), whereas the efficiency of each strategy was 22.4% (95% CI, 22.5% to 26.3%), 52.7% (95% CI, 50.5% to 54.9%), and 87.8% (95% CI, 86.3% to 89.2%), respectively. Conclusions Physician gestalt was safer but less efficient than existing models. Clinical prediction models could help reduce the overuse of blood cultures.

Narrow-gap semiconductors with visible light absorption capability have attracted attention as photofunctional materials. H

Na0.44MnO2 (NMO) with tunnel-type structure is a reference cathode material for rechargeable Na-ion batteries. In this work, the structural, electrochemical and computational investigations are combined to study the properties of this material, particularly in reference to Cu doping in the structure. For the first time, molecular dynamics (MD) is used to obtain insights into the mechanisms of Na+ diffusion in NMO, highlighting the role of structural modifications and Na distribution. The main results allow to investigate the implication of high temperature treatments and the effect of Cu doping on the defect and transport properties of the material with tunnel-type structure. From an experimental point of view, the subtitution promotes an increased stability of the material upon cycling and an improved capacity particularly at higher discharging rates, that stems from the synergistic effects of composition, morphology and multiple polymorphs in the sample.

Honeycomb layered oxides constitute an emerging class of materials that show interesting physicochemical and electrochemical properties. However, the development of these materials is still limited. Here, we report the combined use of alkali atoms ($\rm Na$ and $\rm K$) to produce a mixed alkali honeycomb layered oxide material, namely, $\rm NaKNi_2TeO_6$. Via transmission electron microscopy measurements, we reveal the local atomic structural disorders characterised by aperiodic stacking and incoherency in the alternating arrangement of $\rm Na$ and $\rm K$ atoms. We also investigate the possibility of mixed electrochemical transport and storage of $\rm Na$ and $\rm K$ ions in $\rm NaKNi_2TeO_6$. In particular, we report an average discharge cell voltage of about $4\, \rm V$ and a specific capacity of around $80\, \rm mAh\, g^{-1}$ at low specific currents (i.e., $< 10\, \rm mA\, g^{-1}$) when a $\rm NaKNi_2TeO_6$-based positive electrode is combined with a room-temperature $\rm NaK$ liquid alloy negative electrode using an ionic liquid-based electrolyte solution. These results represent a step towards the use of tailored cathode active materials for dendrite-free electrochemical energy storage systems exploiting room-temperature liquid alkali metal alloy materials., 39 Pages, 7 Figures, 1 Cover Art

Ubiquitin-specific protease 18 (USP18) is a well-established innate immune factor in vertebrates. Although Anatidae birds rarely exhibit distinctive clinical signs during high pathogenicity avian influenza virus (HPAIV) infections, some virus strains cause deadly diseases. Here, we investigated the association between USP18 expression and pathogenicity during HPAIV infections in the Anatidae mallard Anas platyrhynchos. First, mallard USP18 gene (duUSP18) was cloned, and its transcriptional variants, with three different open reading frames, were characterized. Experimental infections with two different pathogenic strains, Miyazaki and Takeo, demonstrated an early induction of duUSP18 mRNA upon HPAIV infection in a bird's whole body in vivo and in primary duck cells in vitro, which was positively associated with pathogenicity in mallards. In addition, duUSP18 knockdown under interferon-β stimulation attenuated viral replication, regardless of pathogenicity. These results indicate a role for duUSP18 in favoring viral replication and virus resistance to type I interferon immunity in mallards.

Proton conductors have found diverse applications such as electrolytes of solid oxide fuel cells (SOFCs), but they are required to have high ionic conductivity at low temperatures and chemical stability. Here, we report a new oxide Ba2LuAlO5, which exhibits higher proton conductivity than 10‒2 S cm‒1 between 350 and 800°C, high diffusivity and high chemical stability without any chemical doping. Ba2LuAlO5 is a hexagonal perovskite-related oxide with highly oxygen deficient h' layers, which enables a large amount of water uptake x = 0.22 in Ba2LuAlO5·x H2O. Ab initio molecular dynamics simulations show that the water molecules dissociate into the h' layer and that protons migrate mainly around the interface of cubic closed packed c layers. These results demonstrate that the high proton conduction allowed by the highly oxygen deficient h' and closed packed c layers is a promising strategy for the exploration and development of high-performance proton conductors.

We report on the growth of single crystals of an electron-doped titanium oxyfluoride, Li2Ti(O,F)3, employing high-temperature electrolysis of TiO2 with a eutectic Li2MoO4-LiF melt. Greenish octahedral-shaped crystals (∼30 μm in size) with a cubic rocksalt-type structure were successfully obtained by precisely tuning the applied voltage. The temperature-dependent magnetic susceptibility data revealed a paramagnetic behavior at low temperatures, ensuring the presence of Ti3+ ions (mean valence number of +3.78; F/Ti ∼ 0.15). The crystals exhibited clear visible-light absorption and produced H2 from water in the presence of a sacrificial reagent under UV-light irradiation. Li2Ti(O,F)3 more efficiently produced H2 compared with a nondoped oxyfluoride Li5Ti2O6F, likely due to the doped electrons for the former. This work highlights a promising electrochemical approach toward growing electron-doped oxyfluoride crystals.

Oxide-ion conductors are important in various applications such as solid-oxide fuel cells. Although zirconia-based materials are widely utilized, there remains a strong motivation to discover electrolyte materials with higher conductivity that lowers the working temperature of fuel cells, reducing cost. Oxide-ion conductors with hexagonal perovskite related structures are rare. Herein, we report oxide-ion conductors based on a hexagonal perovskite-related oxide Ba7Nb4MoO20. Ba7Nb3.9Mo1.1O20.05 shows a wide stability range and predominantly oxide-ion conduction in an oxygen partial pressure range from 2 × 10−26 to 1 atm at 600 °C. Surprisingly, bulk conductivity of Ba7Nb3.9Mo1.1O20.05, 5.8 × 10−4 S cm−1, is remarkably high at 310 °C, and higher than Bi2O3- and zirconia-based materials. The high conductivity of Ba7Nb3.9Mo1.1O20.05 is attributable to the interstitial-O5 oxygen site, providing two-dimensional oxide-ion O1−O5 interstitialcy diffusion through lattice-O1 and interstitial-O5 sites in the oxygen-deficient layer, and low activation energy for oxide-ion conductivity. Present findings demonstrate the ability of hexagonal perovskite related oxides as superior oxide-ion conductors.

Critical to the development of solid electrolytes in clean energy applications is a new class of proton conductors. Here, we report the first example of proton conductors belonging to (110) layered perovskites. BaNdScO4 and new materials, BaNd1−xAxScO4−x/2 (x = 0.05–0.5 for A = Mg, Ca, Sr and Ba), BaSmScO4 and BaGdScO4, with an orthorhombic Cmcm BaNdInO4-type structure were synthesized. BaNd0.8Ca0.2ScO3.9 shows the highest electrical conductivity among the synthesized samples and the highest proton conductivity at 650–750 °C and 850–950 °C among the modular perovskites. BaNd0.8Ca0.2ScO3.9 exhibits higher proton conductivity than BaNdScO4 (ex. 27 times higher at 600 °C), which is attributable to the formation of oxygen vacancies, leading to incorporation of water. The present structure analysis using the neutron diffraction data of the BaNd0.8Ca0.2ScO3.9 sample annealed in wet air (BaNd0.8Ca0.2ScO3.934(2)H0.067(3)·0.283 H2O) and DFT calculations indicate that the protons of BaNd0.8Ca0.2ScO3.9 are coordinated with O3 atoms forming OH− and that oxygen vacancies exist at O2 and O3 sites near the interface between the perovskite-like slab and the A-type rare earth oxide-like layer. DFT calculations gave a slightly lower energy barrier for the proton migration along the c axis via inter- and intra-octahedral hopping compared to those along a and b axes, suggesting one-dimensional proton migration along the c axis at low temperatures and possible three-dimensional proton diffusion at high temperatures. Thus, (110) layered perovskites based on BaNdScO4 are a new class of proton conductors, where inter- and intra-octahedral hopping plays an important role in proton conduction. This work also reports oxide-ion conduction in orthorhombic Cmcm (110) layered perovskites. These findings would offer new routes for the design of novel proton/oxide-ion conductors based on (110) layered perovskites.

Hexagonal perovskite-related oxides have garnered a great deal of research interest because of their high oxide-ion conductivity at intermediate temperatures, with Ba

The thermal stability of oxynitride perovskites is very important for the fabrication of their dense ceramics. In this study, a solid solution of the oxynitride perovskite Sr1-xLaxTa1-xTixO2N was prepared via the ammonia nitridation of oxide precursors. The oxynitrides products obtained at x ≤ 0.2 and x ≥ 0.7 had tetragonal and triclinic perovskite-type structures, respectively. A neutron diffraction study on the oxynitride product obtained at x = 0.2 indicated that this tetragonal perovskite had a cis-type anion distribution similarly to SrTaO2N. The tetragonal perovskite released a part of nitrogen at approximately 1000 °C in a nitrogen atmosphere while maintaining the perovskite structure at least to 1450 °C. The oxynitride perovskites at x ≥ 0.5 gradually decomposed to a mixture of LaTiO2N, LaTiO3, La(OH)3, La2O3, TiN and TaO above 1100 °C.

A series of aluminate-based oxyhydrides, Sr3–xAxAlO4H (A = Ca, Ba; x = 0, 1), has been synthesized by high-temperature reaction of oxide and hydride precursors under a H2 atmosphere. Their crystal ...

Objective: To evaluate the added value of inflammatory markers to vital signs to predict mortality in patients suspected of severe infection. Methods: This study was conducted at an acute care hospital (471-bed capacity). Consecutive adult patients suspected of severe infection who presented to either ambulatory care or the emergency department from April 2015 to March 2017 were retrospectively evaluated. A prognostic model for predicting 30-day in-hospital mortality based on previously established vital signs (systolic blood pressure, respiratory rate, and mental status) was compared with an extended model that also included four inflammatory markers (C-reactive protein, neutrophil-lymphocyte ratio, mean platelet volume, and red cell distribution width). Measures of interest were model fit, discrimination, and the net percentage of correctly reclassified individuals at the pre-specified threshold of 10% risk. Results: Of the 1015 patients included, 66 (6.5%) died. The extended model including inflammatory markers performed significantly better than the vital sign model (likelihood ratio test: p < 0.001), and the c-index increased from 0.69 (range 0.67–0.70) to 0.76 (range 0.75–0.77) (p = 0.01). All included markers except C-reactive protein showed significant contribution to the model improvement. Among those who died, 9.1% (95% CI −2.8–21.8) were correctly reclassified by the extended model at the 10% threshold. Conclusions: The inflammatory markers except C-reactive protein showed added predictive value to vital signs. Future studies should focus on developing and validating prediction models for use in individualized predictions including both vital signs and the significant markers.

Metal node design is crucial for obtaining structurally diverse coordination polymers (CPs) and metal?organic frameworks with desirable properties; however, FeII ions are exclusively six-coordinated. Herein, we present a cyanide-bridged three-dimensional (3D) CP, FePd(CN)4, bearing four-coordinate FeII ions, which is synthesized by thermal treatment of a two-dimensional (2D) six-coordinate FeII CP, Fe(H2O)2Pd(CN)4?4?H2O, to remove water molecules. Atomic-resolution transmission electron microscopy and powder X-ray and neutron diffraction measurements revealed that the FePd(CN)4 structure is composed of a two-fold interpenetrated PtS topology network, where the FeII center demonstrates an intermediate geometry between tetrahedral and square-planar coordination. This four-coordinate FeII center with the distorted geometry can act as a thermo-responsive flexible node in the PtS network.

Undoped layered oxynitrides have not been considered as promising H2 -evolution photocatalysts because of the low chemical stability of oxynitrides in aqueous solution. Here, we demonstrate the synthesis of a new layered perovskite oxynitride, K2 LaTa2 O6 N, as an exceptional example of a water-tolerant photocatalyst for H2 evolution under visible light. The material underwent in-situ H+ /K+ exchange in aqueous solution while keeping its visible-light-absorption capability. Protonated K2 LaTa2 O6 N, modified with an Ir cocatalyst, exhibited excellent catalytic activity toward H2 evolution in the presence of I- as an electron donor and under visible light; the activity was six times higher than Pt/ZrO2 /TaON, one of the best-performing oxynitride photocatalysts for H2 evolution. Overall water splitting was also achieved using the Ir-loaded, protonated K2 LaTa2 O6 N in combination with Cs-modified Pt/WO3 as an O2 evolution photocatalyst in the presence of an I3 - /I- shuttle redox couple.

Oxide-ion conductors have received considerable attention owing to their wide applicability in many electrochemical devices such as solid-oxide fuel cells, oxygen gas sensors, and oxygen separation membranes. CsBi2Ti2NbO10−δ (δ represents oxygen-vacancy content), a Dion–Jacobson-type layered perovskite, exhibits higher oxide-ion conductivity than the conventional yttria-stabilized zirconia. However, CsBi2Ti2NbO10−δ undergoes a phase transition around 800 K, which may make it unsuitable for practical applications. In this study, we present a Dion–Jacobson-type oxide-ion conductor CsLa2Ti2NbO10−δ that does not show phase transitions in the temperature range from 297 K to 1073 K. CsR2Ti2NbO10−δ (R = La, Pr, Nd and Sm) oxides were synthesized. CsLa2Ti2NbO10−δ shows the highest total electrical conductivity (σtot) among them. σtot of CsLa2Ti2NbO10−δ is almost constant from 10−22 to 1 atm oxygen partial pressure at 873 K, supporting oxide-ion conduction. Proton conductivity was not observed between 673 K and 1273 K because the σtot measured in dry air agreed well with that measured in wet air at the same temperature. Electromotive force measurements by an oxygen concentration cell show an oxide-ion transport number of 0.99 in CsLa2Ti2NbO10−δ at 873 K, which indicates that the major charge carrier in CsLa2Ti2NbO10−δ is the oxide ion. The electrical properties were examined by an AC impedance method, showing a bulk ionic conductivity of 1.01 × 10−3 S cm−1 at 1276 K with an activation energy of 0.932(2) eV. Neutron-diffraction and synchrotron X-ray diffraction data were processed using Rietveld refinements and revealed no phase transitions from 297 K to 1073 K in CsLa2Ti2NbO10−δ. Bond-valence-based energy landscapes of a test oxide ion in CsLa2Ti2NbO10−δ strongly suggest that oxide ions diffuse along the edges of the octahedra in perovskite-like slabs, leading to two-dimensional (2D) oxide-ion diffusion. We attribute the oxide-ion conduction in CsLa2Ti2NbO10−δ to the existence of oxygen vacancies, anisotropic thermal motions of oxygen atoms, and the 2D oxide-ion conducting slab.

The first example of both cation- and anion-ordered rutile-type derivative LiTeO3(OH) (= HLiTeO4) has been discovered. LiTeO3(OH) belongs to a non-centrosymmetric space group P21. Both cations (Li+/Te6+) and anions (O2-/OH-) exhibit occupational ordering in LiTeO3(OH).

The Goose/Guangdong-lineage (Gs/Gd) H5 high pathogenicity avian influenza viruses (HPAIVs) spread among poultry and wild birds worldwide; an association has been identified between the migration of wild birds and spread of HPAIVs. Every autumn-spring season, the mallard (Anas platyrhynchos) migrates to Japan in substantial numbers for overwintering; however, to the best of our knowledge, no virological studies have focused on mallards' susceptibility to the HPAIVs in Japan. To evaluate the susceptibility of mallards to infection with Gs/Gd H5 HPAIVs isolated during previous outbreaks in Japan, we experimentally infected the birds with various virus strains: A/chicken/Yamaguchi/7/2004 (H5N1) (clade 2.5), A/chicken/Miyazaki/K11/2007 (H5N1) (clade 2.2), A/whooper swan/Akita/1/2008 (H5N1) (clade 2.3.2), A/mandarin duck/Miyazaki/22M-765/2011 (H5N1) (clade 2.3.2.1c), A/duck/Chiba/26-372-48/2014 (H5N8) (clade 2.3.4.4c), A/duck/Hyogo/1/2016 (H5N6) (clade 2.3.4.4e) and A/mute swan/Shimane/3211A002/2017 (H5N6) (clade 2.3.4.4b). The birds exhibited high tracheal shedding for a prolonged period, particularly those infected with A/duck/Hyogo/1/2016 (H5N6). Various clinical manifestations ranging from asymptomatic to mild (corneal opacity) infections to neurological disorders accompanied by mortality were noted depending on the virus strain. Furthermore, virus-infected mallards contaminated both cohoused mallards and water in their surroundings. Thus, mallards may disseminate viruses in the environment, thereby influencing HPAI outbreaks in Japan. Therefore, mallards represent an important migratory bird species that spread HPAIVs in Japan.