In Silico Analyses of Vertebrate G-Protein-Coupled Receptor Fusions United With or Without an Additional Transmembrane Sequence Indicate Classification into Three Groups of Linkers

Natural G-protein-coupled receptors (GPCRs) rarely have an additional transmembrane (TM) helix, such as an artificial TM-linker that can unite two class A GPCRs in tandem as a single-polypeptide chain (sc). Here, we report that three groups of TM-linkers exist in the intervening regions of natural GPCR fusions from vertebrates: (1) the original consensus (i.e., consensus 1) and consensus 2~4 (related to GPCR itself or its receptor-interacting proteins); (2) the consensus but GPCR-unrelated ones, 1~7; and (3) the inability to apply 1/2 that show no similarity to any other proteins. In silico analyses indicated that all natural GPCR fusions from Amphibia lack a TM-linker, and reptiles have no GPCR fusions; moreover, in either the GPCR-GPCR fusion or fusion protein of (GPCR monomer) and non-GPCR proteins from vertebrates, excluding tetrapods, i.e., so-called fishes, TM-linkers differ from previously reported mammalian and are avian sequences and are classified as Groups 2 and 3. Thus, previously reported TM-linkers were arranged: Consensus 1 is [T(I/A/P)(A/S)-(L/N)(I/W/L)(I/A/V)GL(L/G)(A/T)(S/L/G)(I/L)] first identified in invertebrate sea anemone Exaiptasia diaphana (LOC110241027) and (330-SPSFLCI-L-SLL-340) identified in a tropical bird Opisthocomus hoazin protein LOC104327099 (XP_009930279.1); GPCR-related consensus 2~4 are, respectively, (371-prlilyavfc fgtatg-386) in the desert woodrat Neotoma lepida A6R68_19462 (OBS78147.1), (363-lsipfcll yiaallgnfi llfvi-385) in Gavia stellate (red-throated loon) LOC104264164 (XP_009819412.1), and (479-ti vvvymivcvi glvgnflvmy viir-504) in a snailfish GPCR (TNN80062.1); In Mammals Neotoma lepida, Aves Erythrura gouldiae, and fishes protein (respectively, OBS83645.1, RLW13346.1 and KPP79779.1), the TM-linkers are Group 2. Here, we categorized, for the first time, natural TM-linkers as rare evolutionary events among all vertebrates.

Inverse-Perovskite Ba3 BO (B = Si and Ge) as a High Performance Environmentally Benign Thermoelectric Material with Low Lattice Thermal Conductivity

High energy-conversion efficiency (ZT) of thermoelectric materials has been achieved in heavy metal chalcogenides, but the use of toxic Pb or Te is an obstacle for wide applications of thermoelectricity. Here, high ZT is demonstrated in toxic-element free Ba3 BO (B = Si and Ge) with inverse-perovskite structure. The negatively charged B ion contributes to hole transport with long carrier life time, and their highly dispersive bands with multiple valley degeneracy realize both high p-type electronic conductivity and high Seebeck coefficient, resulting in high power factor (PF). In addition, extremely low lattice thermal conductivities (κlat ) 1.0-0.4 W m-1  K-1 at T = 300-600 K are observed in Ba3 BO. Highly distorted O-Ba6 octahedral framework with weak ionic bonds between Ba with large mass and O provides low phonon velocities and strong phonon scattering in Ba3 BO. As a consequence of high PF and low κlat , Ba3 SiO (Ba3 GeO) exhibits rather high ZT = 0.16-0.84 (0.35-0.65) at T = 300-623 K (300-523 K). Finally, based on first-principles carrier and phonon transport calculations, maximum ZT is predicted to be 2.14 for Ba3 SiO and 1.21 for Ba3 GeO at T = 600 K by optimizing hole concentration. Present results propose that inverse-perovskites would be a new platform of environmentally-benign high-ZT thermoelectric materials.

Antisite-Defects Control of Magnetic Properties in MnSb2Te4

The intrinsic magnetic topological materials Mn(Sb/Bi)2n+2Te3n+4 have attracted extensive attention due to their topological quantum properties. Although, the Mn-Sb/Bi antisite defects have been frequently reported to exert significant influences on both magnetism and band topology, their formation mechanism and the methods to manipulate their distribution and concentration remain elusive. Here, we present MnSb2Te4 as a typical example and demonstrate that Mn-Sb antisite defects and magnetism can be tuned by controlling the crystal growth conditions. The cooling rate is identified as the primary key parameter. Magnetization and chemical analysis demonstrate that a slower cooling rate would lead to a higher Mn concentration, a higher magnetic transition temperature, and a higher saturation moment. Further analysis indicates that the Mn content at the original Mn site (MnMn, 3a site) varies more significantly with the cooling rate than the Mn content at the Sb site (MnSb, 6c site). Based on experimental observations, magnetic phase diagrams regarding MnMn and MnSb concentrations are constructed. With the assistance of first-principles calculations, it is demonstrated that the Mn-Sb mixing states primarily result from the mixing entropy and the growth kinetics. The present findings offer valuable insights into defects engineering for preparation of two-dimensional quantum materials.

Degenerated Hole Doping and Ultra-Low Lattice Thermal Conductivity in Polycrystalline SnSe by Nonequilibrium Isovalent Te Substitution

Tin mono-selenide (SnSe) exhibits the world record of thermoelectric conversion efficiency ZT in the single crystal form, but the performance of polycrystalline SnSe is restricted by low electronic conductivity (σ) and high thermal conductivity (κ), compared to those of the single crystal. Here an effective strategy to achieve high σ and low κ simultaneously is reported on p-type polycrystalline SnSe with isovalent Te ion substitution. The nonequilibrium Sn(Se1- x Tex ) solid solution bulks with x up to 0.4 are synthesized by the two-step process composed of high-temperature solid-state reaction and rapid thermal quenching. The Te ion substitution in SnSe realizes high σ due to the 103 -times increase in hole carrier concentration and effectively reduced lattice κ less than one-third at room temperature. The large-size Te ion in Sn(Se1- x Tex ) forms weak SnTe bonds, leading to the high-density formation of hole-donating Sn vacancies and the reduced phonon frequency and enhanced phonon scattering. This result-doping of large-size ions beyond the equilibrium limit-proposes a new idea for carrier doping and controlling thermal properties to enhance the ZT of polycrystalline SnSe.

High-Mobility Metastable Rock-Salt Type (Sn,Ca)Se Thin Film Stabilized by Direct Epitaxial Growth on a YSZ (111) Single-Crystal Substrate

Metastable cubic (Sn_1-xPb_x)Se with x ≥ 0.5 is expected to be a high mobility semiconductor due to its Dirac-like electronic state, but it has an excessively high carrier concentration of ∼10¹⁹ cm^-3 and is not suitable for semiconductor device applications such as thin film transistors and solar cells. Further, thin films of (Sn_1-xPb_x)Se require a complicated synthesis process because of the high vapor pressure of Pb. We herein report the direct growth of metastable cubic (Sn_1-xCa_x)Se films alloyed with CaSe, which has a wider bandgap and lower vapor pressure than PbSe. The cubic (Sn_1-xCa_x)Se epitaxial films with x = 0.4-0.8 are stabilized on YSZ (111) single crystalline substrates by pulsed laser deposition. (Sn_1-xCa_x)Se has a direct-transition-type bandgap, and the bandgap energy can be varied from 1.4 eV (x = 0.4) to 2.0 eV (x = 0.8) by changing x. These films with x = 0.4-0.6 show p-type conduction with low hole carrier concentrations of ∼10¹⁷ cm^-3. Hall mobility analysis suggests that the hole transport would be dominated by 180° rotational domain structures, which is specific to (111) oriented epitaxial films. However, it, in turn, clarifies that the in-grain carrier mobility in the (Sn_0.6Ca_0.4)Se film is as high as 322 cm²/(Vs), which is much higher than those in thermodynamically stable layered SnSe and other Sn-based layered semiconductor films at room temperature. Therefore, the present results prove the potential of high mobility (Sn_1-xCa_x)Se films for semiconductor device applications via a simple thin-film deposition process.

Design, Synthesis, and Optoelectronic Properties of the High-Purity Phase in Layered AETMN2 (AE = Sr, Ba; TM = Ti, Zr, Hf) Semiconductors

We report the synthesis and optoelectronic properties of high phase-purity (>94 mol %) bulk polycrystals of KCoO₂-type layered nitrides AETMN₂ (AE = Sr, Ba; and TM = Ti, Zr, Hf), which are expected to exhibit unique electron transport properties originating from their natural two-dimensional (2D) electronic structure, but high-purity intrinsic samples have yet been reported. The bulks were synthesized using a solid-state reaction between AENH and TMN precursors with NaN₃ to achieve high N chemical potential during the reaction. The AETMN₂ bulks are n-type semiconductors with optical band gaps of 1.63 eV for SrTiN₂, 1.97 eV for BaZrN₂, and 2.17 eV for BaHfN₂. SrTiN₂ and BaZrN₂ bulks show degenerated electron conduction due to the natural high-density electron doping and paramagnetic behavior in all of the temperature ranges examined, while such unintentional carrier generation is largely suppressed in BaHfN₂, which exhibits nondegenerated electron conduction. The BaHfN₂ sample also exhibits weak ferromagnetic behavior at temperatures lower than 35 K. Density functional theory calculations suggest that the high-density electron carriers in SrTiN₂ come from oxygen impurity substitution at the N site (O_N) acting as a shallow donor even if the high-N chemical potential synthesis conditions are employed. On the other hand, the formation energy of O_N becomes larger in BaHfN₂ because of the stronger TM-N chemical bonds. Present results demonstrate that the easiness of impurity incorporation is designed by density functional calculations to produce a more intrinsic semiconductor in wider chemical conditions, opening a way to cultivating novel functional materials that are sensitive to atmospheric impurities and defects.

Breaking of Thermopower-Conductivity Trade-Off in LaTiO3 Film around Mott Insulator to Metal Transition

Introducing artificial strain in epitaxial thin films is an effective strategy to alter electronic structures of transition metal oxides (TMOs) and to induce novel phenomena and functionalities not realized in bulk crystals. This study reports a breaking of the conventional trade-off relation in thermopower (S)-conductivity (σ) and demonstrates a 2 orders of magnitude enhancement of power factor (PF) in compressively strained LaTiO3 (LTO) films. By varying substrates and reducing film thickness down to 4 nm, the out-of-plane to the in-plane lattice parameter ratio is controlled from 0.992 (tensile strain) to 1.034 (compressive strain). This tuning induces the electronic structure change from a Mott insulator to a metal and leads to a 103 -fold increase in σ up to 2920 S cm-1 . Concomitantly, the sign of S inverts from positive to negative, and both σ and S increase and break the trade-off relation between them in the n-type region. As a result, the PF (=S2 σ) is significantly enhanced to 300 µW m- 1 K-2 , which is 102 times larger than that of bulk LTO. Present results propose epitaxial strain as a means to finely tune strongly correlated TMOs close to their Mott transition, and thus to harness the hidden large thermoelectric PF.

Large phonon drag thermopower boosted by massive electrons and phonon leaking in LaAlO3/LaNiO3/LaAlO3 heterostructure

An unusually large thermopower (S) enhancement is induced by heterostructuring thin films of the strongly correlated electron oxide LaNiO₃. The phonon-drag effect, which is not observed in bulk LaNiO₃, enhances S for thin films compressively strained by LaAlO₃ substrates. By a reduction in the layer thickness down to three unit cells and subsequent LaAlO₃ surface termination, a 10 times S enhancement over the bulk value is observed due to large phonon drag S (S_g), and the S_g contribution to the total S occurs over a much wider temperature range up to 220 K. The S_g enhancement originates from the coupling of lattice vibration to the d electrons with large effective mass in the compressively strained ultrathin LaNiO₃, and the electron-phonon interaction is largely enhanced by the phonon leakage from the LaAlO₃ substrate and the capping layer. The transition-metal oxide heterostructures emerge as a new playground to manipulate electronic and phononic properties in the quest for high-performance thermoelectrics.

Differential drivers of intraspecific and interspecific competition during malaria-helminth co-infection

Various host and parasite factors interact to determine the outcome of infection. We investigated the effects of two factors on the within-host dynamics of malaria in mice: initial infectious dose and co-infection with a helminth that limits the availability of red blood cells (RBCs). Using a statistical, time-series approach to model the within-host ‘epidemiology’ of malaria, we found that increasing initial dose reduced the time to peak cell-to-cell parasite propagation, but also reduced its magnitude, while helminth co-infection delayed peak cell-to-cell propagation, except at the highest malaria doses. Using a mechanistic model of within-host infection dynamics, we identified dose-dependence in parameters describing host responses to malaria infection and uncovered a plausible explanation of the observed differences in single vs co-infections. Specifically, in co-infections, our model predicted a higher background death rate of RBCs. However, at the highest dose, when intraspecific competition between malaria parasites would be highest, these effects of co-infection were not observed. Such interactions between initial dose and co-infection, although difficult to predict a priori, are key to understanding variation in the severity of disease experienced by hosts and could inform studies of malaria transmission dynamics in nature, where co-infection and low doses are the norm.

Ion Substitution Effect on Defect Formation in Two-Dimensional Transition Metal Nitride Semiconductors, AETiN2 (AE = Ca, Sr, and Ba)

A layered semiconductor, SrTiN₂, has an interesting crystal structure as a two-dimensional (2D) electron system embedded in a three-dimensional bulk periodic structure because it has alternate stacking of a SrN blocking layer and a TiN conduction layer, in which the Ti 3d_xy orbital forms the conduction band minimum (CBM) similar to the SrTiO₃-based thin-film heterostructure. However, SrTiN₂ has been reported to exhibit nearly degenerate conduction, but we reported that it would be due to the easy formation of nitrogen vacancies and oxygen impurities from air. In this paper, we extend the materials to family compounds, alkaline earth (AE) ion-substituted, AETiN₂ (AE = Ca, Sr, and Ba), and investigated how we can suppress the defect formation by (hybrid) density functional theory calculations. All AETiN₂ compounds possess thermodynamic stability in the wide nitrogen (N) chemical potential window. Especially, CaTiN₂ is the most stable even against N-poor conditions. Unintentional carrier generation occurs due to the nitrogen vacancies (V_N), oxygen substitution (O_N), and hydrogen anion substitution (H_N) at the nitrogen sites. The V_N and H_N impurities can be suppressed under N-moderate and N-rich conditions. The O_N defect is easily formed in SrTiN₂ and also in BaTiN₂ under N-rich conditions, but its formation can be suppressed in CaTiN₂. Present results suggest that high-purity CaTiN₂ can be obtained under wider N chemical conditions, which would lead to the realization of the novel functional properties originating from Ti 3d_xy 2D bands embedded in the bulk crystal structure.

Reversible 3D-2D structural phase transition and giant electronic modulation in nonequilibrium alloy semiconductor, lead-tin-selenide

Material properties depend largely on the dimensionality of the crystal structures and the associated electronic structures. If the crystal-structure dimensionality can be switched reversibly in the same material, then a drastic property change may be controllable. Here, we propose a design route for a direct three-dimensional (3D) to 2D structural phase transition, demonstrating an example in (Pb_1-x Sn _x )Se alloy system, where Pb²⁺ and Sn²⁺ have similar ns² pseudo-closed shell configurations, but the former stabilizes the 3D rock-salt-type structure while the latter a 2D layered structure. However, this system has no direct phase boundary between these crystal structures under thermal equilibrium. We succeeded in inducing the direct 3D-2D structural phase transition in (Pb_1-x Sn _x )Se alloy epitaxial films by using a nonequilibrium growth technique. Reversible giant electronic property change was attained at x ~ 0.5 originating in the abrupt band structure switch from gapless Dirac-like state to semiconducting state.

Strain Engineering at Heterointerfaces: Application to an Iron Pnictide Superconductor, Cobalt-Doped BaFe2As2

We propose a unique strategy to apply stronger strain at heterointerfaces than conventional epitaxial strain methods to extract hidden attractive physical/chemical properties in materials. This strategy involves precisely accounting for the epitaxial strain induced by lattice mismatch as well as the differences in the thermal expansion coefficients and compressibilities of epitaxial films and substrates. We selected optimally cobalt-doped BaFe₂As₂(Ba122:Co), an iron-based superconductor with a bulk critical temperature (T_c) of 22 K, as a model material and four types of single-crystal substrates. Ba122:Co was selected because its T_c is robust to hydrostatic pressure but sensitive to epitaxial strain (i.e., one of the anisotropic strains), and the selected substrates entirely cover the positive/negative lattice mismatches, thermal expansion coefficients, and compressibilities with respect to Ba122:Co. With strong anisotropic strain successfully induced by film growth, external hydrostatic pressurizing, and cooling processes, we observed unique carrier transport properties in Ba122:Co epitaxial films on CaF₂ and BaF₂ substrates including (i) upturn behavior in the temperature dependence of the longitudinal resistivity, (ii) negative magnetoresistance, (iii) large enhancement of anomalous Hall effects in the epitaxial films on CaF₂, and (iv) enhancement of T_c to 27 K in the epitaxial films on BaF₂. These results demonstrate the effectiveness of our strategy, and this approach can be further extended to other inorganic materials in thin-film form.

Stable and Tunable Current-Induced Phase Transition in Epitaxial Thin Films of Ca2RuO4

Owing to the recent discovery of the current-induced metal-insulator transition and unprecedented electronic properties of the concomitant phases of calcium ruthenate Ca₂RuO₄, it is emerging as an important material. To further explore the properties, the growth of epitaxial thin films of Ca₂RuO₄ is receiving more attention, as high current densities can be applied to thin-film samples and the amount can be precisely controlled in an experimental environment. However, it is difficult to grow high-quality thin films of Ca₂RuO₄ due to the easy formation of the crystal defects originating from the sublimation of RuO₄; therefore, the metal-insulator transition of Ca₂RuO₄ is typically not observed in the thin films. Herein, a stable current-induced metal-insulator transition is achieved in the high-quality thin films of Ca₂RuO₄ grown by solid-phase epitaxy under high growth temperatures and pressures. In the Ca₂RuO₄ thin films grown by ex situ annealing at >1200 °C and 1.0 atm, continuous changes in the resistance of over 2 orders of magnitude are induced by currents with a precise dependence of the resistance on the current amplitude. A hysteretic, abrupt resistive transition is also observed in the thin films from the resistance-temperature measurements conducted under constant-voltage (variable-current) conditions with controllability of the transition temperature. A clear resistive switching by the current-induced transition is demonstrated in the current-electric-field characteristics, and the switching currents and fields are shown to be very stable. These results represent a significant step toward understanding the high-current-density properties of Ca₂RuO₄ and the future development of Mott-electronic devices based on electricity-driven transitions.

FRI0097 EFFECTS OF BIOLOGICAL DISEASE-MODIFYING ANTI-RHEUMATIC DRUG TREATMENT ON PHYSICAL ACTIVITY, MUSCLE POWER, AGILITY AND INHIBITION OF FALL IN PATIENTS WITH RHEUMATOID ARTHRITIS -THE 2-YEAR RESULTS

Background:

Treatment with biological DMARDs (bDMARDs) rapidly improves signs and symptoms in patients with rheumatoid arthritis (RA). The efficacy of these bDMARDs was evaluated using composite measures or biomarkers used in daily clinical practice or clinical studies. Although a rapid improvement in composite measures or biomarkers is important in the treatment of RA, the primary goal of treatment is improvement of long-term health-related quality of life (HR-QOL) [1]. HR-QOL is evaluated based on physical functions (PF) such as muscle power and agility. We reported the 1-year results of our study presented at EULAR 2019 [2]. The present study was conducted to investigate the 2-year results of our study by including more patents than those included in the previous one.

Objectives:

This study was aimed at investigating the efficacy of bDMARDs with respect to PF and fall risk in RA patients.

Methods:

At our institute, in addition to routine rheumatology evaluation, periodic evaluation of physical function is performed by staff members in our rehabilitation center in RA patients in whom the first bDMARD treatment was initiated in Oct. 2015–Feb. 2018. In total, 41 cases were registered in this study. Evaluation of PF included evaluation of muscle power [grasping power (GP) and knee extension power (KEP)]; agility [time up and go test (TUG) and 10-m walking time (10 mW)]; and a questionnaire using modified HAQ, portable fall risk index [3], and the 25-question geriatric locomotive function scale (locomo25) [4] at baseline (BL), which implies the time at the initiation of bDMARD treatment, i.e., 1, 3, 6, 12, and 24 months. Disease activity of RA was evaluated at the same time points. Although 2 years had elapsed from BL in 37 patients, 13 patients dropped out from the evaluation of physical function owing to cessation of bDMARD treatment, rejection of evaluation for physical function, or major joint surgery performed in a patient. The results of 24 patients who completed the evaluation at 24 months were investigated in this study.

Results:

Baseline characteristics of the 24 patients were as follows: mean age 60.8 years, RA duration 12.3 years, mean SDAI 19.0, and mean CRP level 2.1 mg/dl. The bDMARDs used in the study were abatacept in 7 patients, adalimumab in 4 patients, tocilizumab in 4 patients, golimumab in 4 patients, etanercept in 3 patients, certolizumab in 1 patient, and an infliximab biosimilar in 1 patients. Data are presented as mean values at BL and at 1, 3, 6, 12, and 24 months (Fig.1). SDAI and CRP levels were significantly improved at and after 1 month. GP and KEP were significantly improved at and after 3 and 6 months. TUG and 10 mW results were significantly improved at and after 3 and 6 months. Modified HAQ results were significantly improved at and after 3 months. Locomo25 scores were significantly improved at and after 1 month. Portable fall risk index values were significantly improved at and after 12 months.

Conclusion:

Although there was a rapid improvement in the signs and symptoms of RA after the initiation of bDMARD treatment, improvement in PF was slightly delayed. Significant improvement of muscle power and agility was achieved after 3–6 months onward. Inhibition of fall risk was achieved at and after 12 months after the initiation of bDMARD treatment. These results suggest that physiotherapy plays a vital role in RA patients who undergo treatment with bDMARDs to gain more rapid improvement of PF.

References:

[1]Smolen JS et al. Ann Rheum Dis, 2016.

[2]Hirano Y et al. Ann Rheum Dis, suppl. 2, 2019.

[3]Toba K et al. Jpn J Geriat, 2005.

[4]Seichi A at al. J Orthop Sci, 2012.

Disclosure of Interests:

Yuji Hirano Speakers bureau: Tanabe-Mitsubishi, Pfizer, Eisai, Abbie, Chugai, Bristol-Meyers, Jansen, Astellas, UCB, Eli-Lilly, Asahikasei, Daiichi-Sankyo, Amgen, Ayako Morisaka: None declared, Hironobu Kosugiyama: None declared, Shiori Inuzuka: None declared, Takeshi Kamiya: None declared, Hiroyuki Mori: None declared, Naohito Morishima: None declared, Tomoji Ishikawa: None declared

Symmetric Ambipolar Thin-Film Transistors and High-Gain CMOS-like Inverters Using Environmentally Friendly Copper Nitride

Oxide semiconductor thin-film transistors (TFTs) are currently used as the fundamental building blocks in commercial flat-panel displays because of the excellent performance of n-channel TFTs. However, except for a few materials, their p-channel performances have not been acceptable. Although some p-type oxide semiconductors exhibit superior hole transport properties, their TFT performances are greatly deteriorated, which is a major obstacle in the development of complementary metal-oxide-semiconductor (CMOS) circuits. Herein, an ionic nitride semiconductor, copper nitride (Cu₃N), composed of environmentally benign elements is shown to exhibit highly symmetric hole and electron transport, indicating its suitability for application in CMOS circuits. We performed a two-step investigation. The first step was to examine the ultimate potential of Cu₃N using an electric-double-layer transistor structure with epitaxial Cu₃N channels measured at 220 K, which exhibited ambipolar operation with hole and electron mobilities of ∼5 and ∼10 cm² V^-1 s^-1, respectively, and a high on/off ratio of ∼10⁵. The second step is to demonstrate the feasibility of TFT circuits with a polycrystalline channel on non-single-crystal (SiO₂/Si) substrates. CMOS-like inverters composed of two polycrystalline Cu₃N ambipolar TFTs on a SiO₂/Si substrate exhibited a high voltage gain of ∼100.

On the Origin of the Negative Thermal Expansion Behavior of YCu

Among the intermetallics and alloys, YCu is an unusual material because it displays negative thermal expansion without spin ordering. The mechanism behind this behavior that is caused by the structural phase transition of YCu has yet to be fully understood. To gain insight into this mechanism, we experimentally examined the crystal structure of the low-temperature phase of YCu and discuss the origin of the phase transition with the aid of thermodynamics calculations. The result shows that the high-temperature (cubic CsCl-type) to low-temperature (orthorhombic FeB-type) structural phase transition is driven by the rearrangement of three covalent bonds, namely, Y-Cu, Y-Y, and Cu-Cu, which compete for the bonding energy and phonon entropy. At low temperatures, the mixing of Y and Cu does not take place easily because of the weak attractive force between these atoms expected from the small negative mixing enthalpy. This causes all three interactions to take part in the bonding, and Y and Cu are segregated to form an FeB-type structure, which is stabilized by internal energy. At higher temperatures, Cu ions are bound loosely with Y ions due to the large Y-Cu distance (3.01 Å), which results in large vibration entropy and stabilizes a CsCl-type crystal structure. In addition, the CsCl-type structure is reinforced by the Y-Y interaction between next-nearest neighbors, resulting in a smaller unit cell volume. The crystal structure has the simple cubic framework of Y containing Cu ions bound loosely at the cavity sites. The calculated frequency of the Y-like phonon modes is much higher than that of the Cu-like modes, indicating the presence of Y-Y covalent interactions in the CsCl-type phase.

Randomized clinical trial of single skin sterilization with a povidone-iodine applicator versus conventional skin sterilization in abdominal surgery

Background

The efficacy of widely used povidone–iodine applicators for skin sterilization in abdominal surgery is unclear. The aim of this trial was to evaluate whether sterilization with a povidone–iodine applicator was not inferior to a conventional sterilization method.

Methods

Patients undergoing elective abdominal surgery were assigned randomly to receive single sterilization with the applicator or conventional sterilization. The primary endpoint was wound infection rate. Secondary endpoints were rate of organ/space surgical‐site infection (SSI), adverse effects of povidone–iodine, amount of povidone–iodine used and total cost of sterilization.

Results

Of 498 patients eligible for the study between April 2015 and September 2017, 240 were assigned and analysed in the applicator group and 246 in the conventional group. Wound infection was detected in 16 patients (6·7 per cent) in the applicator group and 16 (6·5 per cent) in the conventional group (absolute difference 0·0016 (90 per cent c.i. −0·037 to 0·040) per cent; P = 0·014 for non‐inferiority). There was no difference between the groups in the organ/space SSI rate (11 patients (4·6 per cent) in the applicator group and 16 (6·5 per cent) in the conventional group. Both the amount of povidone–iodine used and the total cost of sterilization were higher in the conventional group than in the applicator group (median 76·7 versus 25 ml respectively, P < 0·001; median €7·0 versus €6·4, P < 0·001). Skin irritation was detected in three patients in the conventional group.

Conclusion

In abdominal surgery, this povidone–iodine applicator was not inferior to conventional sterilization in terms of the wound infection rate, and it is cheaper. Registration number: UMIN000018231 (http://www.umin.ac.jp/ctr/).

Talbot interferometry for imaging two-dimensional electron density distribution over discharge plasma with higher sensitivity

The basic properties of a Talbot interferometer implementing pinhole arrays were experimentally and numerically investigated for the improvement of measurement sensitivity of laser wavefront sensors utilized for electron density imaging over discharge plasmas. A numerical simulation using a plane wave decomposition method indicated that the pinhole arrays with a pitch of 300 μm and a pinhole diameter of 150 μm were most suitable for the measurement of the millimetre-scale discharge plasmas, in consideration of the spatial resolution and measurement accuracy. The plane wave decomposition simulation expected that the measurement sensitivity of the 8th-Talbot-length interferometer could be improved by a factor of 4 compared with the previously developed Shack-Hartmann type laser wavefront sensors, which was experimentally verified by the self-image behavior of the pinhole arrays. The Talbot interferometric system was successfully used for electron density imaging over the vacuum arcs generated between a 3-mm gap. The electron density image observed by the Talbot interferometers was in excellent agreement with that visualized by the previously developed Shack-Hartmann sensors. The practical notification for the pinhole array fabrication was also presented.

Investigation of factors related to the occurrence of osteochondral lesions of the talus by 3D bone morphology of the ankle

Aims

The aims of this study were to evaluate the morphology of the ankle in patients with an osteochondral lesion of the talus using 3D CT, and to investigate factors that predispose to this condition.

Patients and Methods

The study involved 19 patients (19 ankles) who underwent surgery for a medial osteochondral lesion (OLT group) and a control group of 19 healthy patients (19 ankles) without ankle pathology. The mean age was significantly lower in the OLT group than in the control group (27.0 vs 38.9 years; p = 0.02). There were 13 men and six women in each group. 3D CT models of the ankle were made based on Digital Imaging and Communications in Medicine (DICOM) data. The medial malleolar articular and tibial plafond surface, and the medial and lateral surface area of the trochlea of the talus were defined. The tibial axis-medial malleolus (TMM) angle, the medial malleolar surface area and volume (MMA and MMV) and the anterior opening angle of the talus were measured.

Results

The mean TMM angle was significantly larger in the OLT group (34.2°, sd 4.4°) than in the control group (29.2°, sd 4.8°; p = 0.002). The mean MMA and MMV were significantly smaller in the OLT group than in the control group (219.8 mm2, sd 42.4) vs (280.5 mm2, sd 38.2), and (2119.9 mm3, sd 562.5) vs (2646.4 mm3, sd 631.4; p < 0.01 and p = 0.01, respectively). The mean anterior opening angle of the talus was significantly larger in the OLT group than in the control group (15.4°, sd 3.9°) vs (10.2°, sd 3.6°; p < 0.001).

Conclusion

3D CT measurements showed that, in patients with a medial osteochondral lesion of the talus, the medial malleolus opens distally, the MMA and MMV are small, and the anterior opening angle of the talus is large. This suggests that abnormal morphology of the ankle predisposes to the development of osteochondral lesions of the talus. Cite this article: Bone Joint J 2018;100-B:1487–90.

Congenital Combined Deficiency of Factor V and Factor VIII

A case of congenital combined deficiency of factor V and factor VIII was reported. The patient, a 9 year old boy, gave a history of epistaxis, hematomas, and of hemorrhages following dental extraction since the age of 2 ; plasma levels of factor V and factor VIII were found to be 16% and 8% of normal, respectively. No one in his family had a deficiency of either factor. The effects of transfusion of normal fresh plasma and whole blood from a patient with hemophilia A were studied. While the former were similar to the pattern as seen in classical hemophilia, the latter consisted of an immediate increase of factor V activity and a delayed increase of factor VIII activity, despite the fact that factor VIII activity was almost absent from the donor’s blood.

Layered Halide Double Perovskites Cs3+nM(II)nSb2X9+3n (M = Sn, Ge) for Photovoltaic Applications

Over the past few years, the development of lead-free and stable perovskite absorbers with excellent performance has attracted extensive attention. Much effort has been devoted to screening and synthesizing this type of solar cell absorbers. Here, we present a general design strategy for designing the layered halide double perovskites Cs_3+nM(II)_nSb₂X_9+3n (M = Sn, Ge) with desired photovoltaic-relevant properties by inserting [MX₆] octahedral layers, based on the principles of increased electronic dimensionality. Compared to Cs₃Sb₂I₉, more suitable band gaps, smaller carrier effective masses, larger dielectric constants, lower exciton binding energies, and higher optical absorption can be achieved by inserting variable [SnI₆] or [GeI₆] octahedral layers into the [Sb₂I₉] bilayers. Moreover, our results show that adjusting the thickness of inserted octahedral layers is an effective approach to tune the band gaps and carrier effective masses in a large range. Our work provides useful guidance for designing the promising layered antimony halide double perovskite absorbers for photovoltaic applications.

Roles of Pseudo-Closed s2 Orbitals for Different Intrinsic Hole Generation between Tl-Bi and In-Bi Bromide Double Perovskites

Although metal halide double perovskites A₂B(I)B(III)X₆ are expected as nontoxic alternatives for lead halide perovskites, recent studies have shown that only Tl(I)-Bi(III) and In(I)-Bi(III) bromides are thermodynamically stable and possess optoelectronic properties suitable for photovoltaic absorbers. Here, we show, through density functional theory calculations, that Tl-Bi and In-Bi bromide double perovskites exhibit significantly different semiconducting behaviors due to the different energy levels of the highest-occupied pseudoclosed s² orbitals of Tl(I) and In(I). While Tl-Bi double perovskites can exhibit semiconducting p-type properties, In-Bi bromide double perovskites exhibit metallic p-type ones regardless of the synthesis condition due to the extremely low formation energy of In vacancy. Such difference makes Tl-Bi bromide double perovskites suitable for optoelectronic applications, but not In-Bi bromide double perovskites. Furthermore, there is a high probability for In to substitute a Bi site, forming a local In-In bromide double perovskite structure with a lower local conduction band minimum, detrimentally affecting the open circuit voltage of In-Bi bromide double perovskite-based thin film solar cells.

Multiple states and roles of hydrogen in p-type SnS semiconductors

The states and roles of hydrogen in p-type SnS are studied by hydrogen plasma treatment and density functional theory calculations.

An Exceptionally Narrow Band-Gap (∼4 eV) Silicate Predicted in the Cubic Perovskite Structure: BaSiO3

The electronic structures of 35 A²⁺B⁴⁺O₃ ternary cubic perovskite oxides, including their hypothetical chemical compositions, were calculated by a hybrid functional method with the expectation that peculiar electronic structures and unique carrier transport properties suitable for semiconductor applications would be hidden in high-symmetry cubic perovskite oxides. We found unique electronic structures of Si-based oxides (A = Mg, Ca, Sr, and Ba, and B = Si). In particular, the unreported cubic BaSiO₃ has a very narrow band gap (4.1 eV) compared with conventional nontransition-metal silicates (e.g., ∼9 eV for SiO₂ and the calculated value of 7.3 eV for orthorhombic BaSiO₃) and a small electron effective mass (0.3m₀, where m₀ is the free electron rest mass). The narrow band gap is ascribed to the nonbonding state of Si 3s and the weakened Madelung potential. The existence of the predicted cubic perovskite structure of BaSiO₃ was experimentally verified by applying a high pressure of 141 GPa. The present finding indicates that it could be possible to develop a new transparent oxide semiconductor of earth abundant silicates if the symmetry of its crystal structure is appropriately chosen. Cubic BaSiO₃ is a candidate for high-performance oxide semiconductors if this phase can be stabilized at room temperature and ambient pressure.

The Unique Electronic Structure of Mg2 Si: Shaping the Conduction Bands of Semiconductors with Multicenter Bonding

The electronic structures of the antifluorite-type compound Mg₂ Si is described in which a sublattice of short cation-cation contacts creates a very low conduction band minimum. Since Mg₂ Si shows n-type conductivity without intentional carrier doping, the present result indicates that the cage defined by the cations plays critical roles in carrier transport similar to those of inorganic electrides, such as 12 CaO⋅7 Al₂ O₃ :e^- and Ca₂ N. A distinct difference in the location of conduction band minimum between Mg₂ Si and the isostructural phase Na₂ S is explained in terms of factors such as the differing interaction strengths of the Si/S 3s orbitals with the cation levels, with the more core-like character of the S 3s leading to a relatively low conduction band energy at the Γ point. Based on these results and previous research on electrides, approaches can be devised to control the energy levels of cation sublattices in semiconductors.

Enhanced critical-current in P-doped BaFe2As2 thin films on metal substrates arising from poorly aligned grain boundaries

Thin films of the iron-based superconductor BaFe2(As1-xPx)2 (Ba122:P) were fabricated on polycrystalline metal-tape substrates with two kinds of in-plane grain boundary alignments (well aligned (4°) and poorly aligned (8°)) by pulsed laser deposition. The poorly aligned substrate is not applicable to cuprate-coated conductors because the in-plane alignment >4° results in exponential decay of the critical current density (Jc). The Ba122:P film exhibited higher Jc at 4 K when grown on the poorly aligned substrate than on the well-aligned substrate even though the crystallinity was poorer. It was revealed that the misorientation angles of the poorly aligned samples were less than 6°, which are less than the critical angle of an iron-based superconductor, cobalt-doped BaFe2As2 (~9°), and the observed strong pinning in the Ba122:P is attributed to the high-density grain boundaries with the misorientation angles smaller than the critical angle. This result reveals a distinct advantage over cuprate-coated conductors because well-aligned metal-tape substrates are not necessary for practical applications of the iron-based superconductors.

Early results of multicenter phase II trial of perioperative oxaliplatin and capecitabine without radiotherapy for high-risk rectal cancer: CORONA I study

BACKGROUNDS

Perioperative introduction of developed chemotherapy into the treatment strategy for locally advanced rectal cancer (LARC) may be a promising option. However, the most prevalent treatment for high-risk LARC remains preoperative chemoradiotherapy (CRT) in Western countries.

PATIENTS AND METHODS

A phase II trial was undertaken to evaluate safety and efficacy of perioperative XELOX without radiotherapy (RT) for patients with high-risk LARC. Patients received 4 cycles of XELOX before and after surgery, respectively. Primary endpoint was disease-free survival.

RESULTS

We enrolled 41 patients between June 2012 and April 2014. The completion rate of the preoperative XELOX was 90.3%. Twenty-nine patients (70.7%) could start postoperative XELOX, 15 of these patients (51.7%) completed 4 cycles. Allergic reaction to oxaliplatin was experienced by 5 patients (17.2%) during postoperative XELOX. One patient received additional RT after preoperative XELOX. Consequently, the remaining 40 patients underwent primary resection. Major complications occurred in 6 of 40 patients (15.0%). Pathological complete response (pCR) rate was 12.2%, and good tumor regression was exhibited in 31.7%. N down-staging (cN+ to ypN0) and T down-staging were detected in 56.7% and 52.5%, respectively. Clinical T4 tumor was a predictor of poor pathological response (p < 0.001).

CONCLUSIONS

We could show the favorable pCR rate after preoperative XELOX alone. However, the T and N down-staging rate was likely to be insufficient. When tumor regression is essential for curative resection, the use of preoperative CRT is likely to be recommended. For patients with massive LN metastasis, the additional Bev to NAC might be a promising option.

Electron Confinement in Channel Spaces for One-Dimensional Electride

Electrides are characteristic of anionic electrons trapped at the structural voids in the host lattice. Electrides are potentially useful in various technological applications; however, electrides, particularly their inorganic subgroup, have been discovered only in limited material systems, notably zero-dimensional [Ca24Al28O64](4+):4e(-) and two-dimensional [Ca2N](+):e(-) and [Y2C](1.8+):1.8e(-). Here, on the basis of density functional theory calculations, we report the first one-dimensional (1D) electride with a [La8Sr2(SiO4)6](4+):4e(-) configuration, in which the four anionic electrons are confined in the channel spaces of the host material. According to this theoretical prediction, an insulator-semiconductor transition originating from electron confinement in the crystallographic channel sites was demonstrated experimentally, where 10.5% of the channel oxygen was removed by reacting an oxygen stoichiometric La8Sr2(SiO4)6O2 precursor with Ti metal at a high temperature. This study not only adds an unprecedented role to silicate apatite as a parent phase to a new 1D electride, but also, and more importantly, demonstrates an effective approach for developing new electrides with the assistance of computational design.

Clinical significance of dual-energy CT-derived iodine quantification in the diagnosis of metastatic LN in colorectal cancer

BACKGROUND

The purpose of this study was to evaluate the diagnostic value of dual-energy computed tomography (DECT) in detecting lymph node (LN) metastasis in patients with colorectal cancer.

METHODS

Data from 81 LNs from 28 patients with colorectal adenocarcinoma were retrospectively analyzed. All patients received DECT before surgery without any neoadjuvant therapy. The diagnostic value was assessed using the iodine concentration (IC).

RESULTS

In the pathological findings, 35 (43.2%) LNs from 13 patients were metastatic and 46 (56.8%) LNs from 17 patients were non-metastatic. The mean IC of metastatic LNs in the portal venous phase (PP) was 1.60 mg/ml, which was significantly lower compared with non-metastatic LNs (3.25 mg/ml, p < 0.001). Receiver operating characteristic (ROC) analysis revealed that the IC in PP had the highest ability to discriminate LN metastasis (area under the ROC curve [AUC] 0.932). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of IC in PP (cutoff 2.1 mg/ml) were 87.0%, 88.6%, 85.3%, 90.0%, and 87.9%, respectively. When clinically obvious metastatic LNs in conventional CT findings were excluded, 50 LNs remained (5 metastatic and 45 non-metastatic LNs). In this subgroup analysis, the IC in PP remained the most powerful predictor of metastatic LNs (cutoff: 2.1 mg/ml, AUC 0.933).

CONCLUSIONS

The evaluation of IC in DECT may improve the diagnostic capabilities of discriminating metastatic LNs. This method may be particularly useful when conventional CT findings lead to equivocal results.

Two distinct effector memory cell populations of WT1 (Wilms' tumor gene 1)-specific cytotoxic T lymphocytes in acute myeloid leukemia patients

Wilms' tumor gene 1 (WT1) protein is a promising tumor-associated antigen for cancer immunotherapy. We have been performing WT1 peptide vaccination with good clinical responses in over 750 patients with leukemia or solid cancers. In this study, we generated single-cell gene-expression profiles of the effector memory (EM) subset of WT1-specific cytotoxic T lymphocytes (CTLs) in peripheral blood of nine acute myeloid leukemia patients treated with WT1 peptide vaccine, in order to discriminate responders (WT1 mRNA levels in peripheral blood decreased to undetectable levels, decreased but stayed at abnormal levels, were stable at undetectable levels, or remained unchanged from the initial abnormal levels more than 6 months after WT1 vaccination) from non-responders (leukemic blast cells and/or WT1 mRNA levels increased relative to the initial state within 6 months of WT1 vaccination) prior to WT1 vaccination. Cluster and principal component analyses performed using 83 genes did not discriminate between responders and non-responders prior to WT1 vaccination. However, these analyses revealed that EM subset of WT1-specific CTLs could be divided into two groups: the "activated" and "quiescent" states; in responders, EM subset of the CTLs shifted to the "quiescent" state, whereas in non-responders, those shifted to the "activated" state following WT1 vaccination. These results demonstrate for the first time the existence of two distinct EM states, each of which was characteristic of responders or non-responders, of WT1-specific CTLs in AML patients, and raises the possibility of using advanced gene-expression profile analysis to clearly discriminate between responders and non-responders prior to WT1 vaccination.

n-type conversion of SnS by isovalent ion substitution: Geometrical doping as a new doping route

Tin monosulfide (SnS) is a naturally p-type semiconductor with a layered crystal structure, but no reliable n-type SnS has been obtained by conventional aliovalent ion substitution. In this work, carrier polarity conversion to n-type was achieved by isovalent ion substitution for polycrystalline SnS thin films on glass substrates. Substituting Pb²⁺ for Sn²⁺ converted the majority carrier from hole to electron, and the free electron density ranged from 10¹² to 10¹⁵ cm⁻³ with the largest electron mobility of 7.0 cm²/(Vs). The n-type conduction was confirmed further by the position of the Fermi level (E_F) based on photoemission spectroscopy and electrical characteristics of pn heterojunctions. Density functional theory calculations reveal that the Pb substitution invokes a geometrical size effect that enlarges the interlayer distance and subsequently reduces the formation energies of Sn and Pb interstitials, which results in the electron doping.