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Field-effect transistors (FETs) have been fabricated with thin films of a series of 2,9-dialkylated phenanthro[1,2-b:8,7-b′]dithiophene derivatives (Cn-PDTs). The FET characteristics of Cn-PDT thin-film FETs with an SiO2 gate dielectric as well as high-k gate dielectrics were recorded, and the dependence of the field-effect mobility, μ, on the number (n) of carbon atoms in the alkyl chains was investigated, showing that the 2,9-didodecylphenanthro[1,2-b:8,7-b′]dithiophene (C12-PDT) thin-film FET displays superior properties, with μs as high as 1.8 cm2 V−1 s−1 for the SiO2 gate dielectric and 2.2 cm2 V−1 s−1 for the HfO2 gate dielectric. The average μ values, 〈μ〉, reach 1.1(5) and 1.8(6) cm2 V−1 s−1, respectively, for the SiO2 and ZrO2 gate dielectrics. Low-voltage operation, showing an absolute average threshold voltage 〈☋Vth☋〉 of ∼11 V, was implemented, together with the above high 〈μ〉 of ∼2 cm2 V−1 s−1. Also, a flexible FET was fabricated with a parylene gate dielectric. The results of this study show the potential of the C12-PDT molecule for application in a high-performance transistor. [ABSTRACT FROM AUTHOR]

The temperature dependence of the resistivity (ρ) of Ag-doped Bi2Se3 (AgxBi2−xSe3) shows insulating behavior above 35 K, but below 35 K, ρ suddenly decreases with decreasing temperature, in contrast to the metallic behavior for non-doped Bi2Se3 at 1.5–300 K. This significant change in transport properties from metallic behavior clearly shows that the Ag doping of Bi2Se3 can effectively tune the Fermi level downward. The Hall effect measurement shows that carrier is still electron in AgxBi2−xSe3 and the electron density changes with temperature to reasonably explain the transport properties. Furthermore, the positive gating of AgxBi2−xSe3 provides metallic behavior that is similar to that of non-doped Bi2Se3, indicating a successful upward tuning of the Fermi level. [ABSTRACT FROM AUTHOR]

We previously discovered multiple superconducting phases in the ammoniated Na-doped FeSe material, (NH3)yNaxFeSe. To clarify the origin of the multiple superconducting phases, the variation of Tc was fully investigated as a function of x in (NH3)yNaxFeSe. The 32 K superconducting phase is mainly produced in the low-x region below 0.4, while only a single phase is observed at x = 1.1, with Tc = 45 K, showing that the Tc depends significantly on x, but it changes discontinuously with x. The crystal structure of (NH3)yNaxFeSe does not change as x increases up to 1.1, i.e., the space group of I4/mmm. The lattice constants, a and c, of the low-Tc phase (Tc = 32.5 K) are 3.9120(9) and 14.145(8) Å, respectively, while a = 3.8266(7) Å and c = 17.565(9) Å for the high-Tc phase (~46 K). The c increases in the high Tc phase, implying that the Tc is directly related to c. In (NH3)yLixFeSe material, the Tc varies continuously within the range of 39 to 44 K with changing x. Thus, the behavior of Tc is different from that of (NH3)yNaxFeSe. The difference may be due to the difference in the sites that the Na and Li occupy. [ABSTRACT FROM AUTHOR]

Abstract: Transistor characteristics and O2 gas sensing properties are investigated for picene thin film field-effect transistors (FETs) with ZrO2, Ta2O5, HfO2 and Ba x Sr1−x TiO3 (x =0.4). The low-voltage operation is achieved using the above oxides with high gate dielectric constant, contrary to SiO2 gate dielectric. The O2 gas sensing is achieved at 11s intervals without any bias stress by an application of pulse drain and gate voltages (V D and V G), in contrast to previous result in which the O2 gas sensing was performed at least at 1h step because of bias stress effect. The actual O2 sensing-speed in the picene thin film FET was ∼10s for 3.8Torr O2, and the O2 sensing limit was concluded to be 0.15–0.38Torr. Furthermore, it has been found that the O2 sensing properties are observed only under irradiation of light with wavelength below 400nm. From the result, we have presented two scenarios for O2 sensing mechanism in picene thin film FET. [Copyright &y& Elsevier]

The local structure of a two-dimensional layered material, Bi 2 Rh 3 Se 2 , in which superconducting (SC) and charge-density wave (CDW) states coexist, was investigated using Bi Lα and Lγ X-ray fluorescence holography (XFH). The crystal of Bi 2 Rh 3 Se 2 adopts a monoclinic lattice with a space group of C 2/ m (No. 12) at room temperature; however, the structure below the CDW transition (∼240 K) is still unclear because of the difficulty in analyzing single-crystal X-ray diffraction. Therefore, information on the crystal structure below 240 K is significant to fully investigate the relationship between the SC and CDW states. Precisely, the value of β has not been definitely determined, i.e. , β ∼ 90° or ∼134° is still unclear. Therefore, the crystal structure above 240 K is still under discussion. In this study, we attempted to determine the crystal structure at 300 and 200 K by comparing the atomic images reconstructed from Bi Lγ holograms with images simulated based on crystal structure models. A Bi Lα hologram was also exploited to determine suitable atomic locations by comparison with the simulated ones. The atomic image simulated with the crystal structure of Bi 2 Rh 3 S 2 below the structural phase transition temperature reproduced well the experimental atomic image at 200 K. Specifically, the line profiles of the reconstructed images at 300 and 200 K, which exactly reflect the intensity of the atomic spots, clearly indicate the structural variation above and below the CDW transition temperature, i.e. , the supercell structure is suggested as the atomic location for Bi 2 Rh 3 Se 2 below the CDW transition temperature.

The structural and superconducting properties of the Bi-based superconductor Bi 2 Rh 3 (Se 1- x S x ) 2 were investigated over a wide pressure range. Bi 2 Rh 3 Se 2 is a superconductor with a superconducting transition temperature, T c , of less than ∼1.0 K, whereas Bi 2 Rh 3 S 2 is a nonsuperconductor. The former shows a clear charge density wave (CDW) phase transition at 240 K and the latter shows a first-order structural phase transition at 165 K, providing the supercell structure. Both compounds have the same crystal structure at ambient temperature and pressure (monoclinic, space group of C 2/ m (No. 12)). This implies the possible formation of solid solution-like phases Bi 2 Rh 3 (Se 1- x S x ) 2 . In this study, we prepared Bi 2 Rh 3 (Se 1- x S x ) 2 ( x = 0-1.0) and investigated its superconducting properties and phase transitions at different x values. Because the superconducting properties and temperature causing the phase transition ( T pt ) are quite different between Bi 2 Rh 3 Se 2 and Bi 2 Rh 3 S 2 , their variation against x is quite intriguing from the viewpoint of the pursuit of physical properties via the replacement of Se with S. In this study, the features of the superconductivity and crystal structure against x were fully explored to depict the phase diagram. Moreover, we investigated the pressure ( p ) dependence of superconductivity and phase transition (CDW or the first-order structural transition) to clarify the interplay between the two ordered states.

The local structure of the two-dimensional van der Waals material, Fe 5- x GeTe 2 , which exhibits unique structural/magnetic phase transitions, was investigated by Te K-edge extended X-ray absorption fine structure (EXAFS) and Te Kα X-ray fluorescence holography (XFH) over a wide temperature range. The formation of a trimer of Te atoms at low temperatures has been fully explored using these methods. An increase in the Te-Fe distance at approximately 150 K was suggested by EXAFS and presumably indicates the formation of a Te trimer. Moreover, XFH displayed clear atomic images of Te atoms. Additionally, the distance between the Te atoms shortened, as confirmed from the atomic images reconstructed from XFH, indicating the formation of a trimer of Te atoms, i.e., a charge-ordered superstructure. Furthermore, Te Kα XFH provided unambiguous atomic images of Fe atoms occupying the Fe1 site; the images were not clearly observed in the Ge Kα XFH that was previously reported because of the low occupancy of Fe and Ge atoms. In this study, EXAFS and XFH clearly showed the local structure around the Te atom; in particular, the formation of Te trimers caused by charge-ordered phase transitions was clearly confirmed. The charge-ordered phase transition is fully discussed based on the structural variation at low temperatures, as established from EXAFS and XFH., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Background: A right-sided aortic arch is a rare congenital vascular structure variation. Right lobectomy is not commonly performed on patients with such a condition. Further, there are no reports on lobectomy under uniportal video-assisted thoracoscopic surgery (VATS) in this patient group., Case Presentation: A 67-year-old man with a right-sided aortic arch and Kommerell diverticulum underwent right upper lobectomy with mediastinal lymph node dissection under uniportal VATS for primary lung cancer. Due to the right descending aorta, which narrows the space of the dorsal hilum, handling of the stapler for stapling the right upper lobe bronchus from the uniport in the 6th intercostal space at the medial axillary line can be challenging. This issue was resolved by manipulating the staple over the azygos vein toward the inferior margin of the aortic arch. Via mediastinal lymphadenectomy, we found that the right recurrent laryngeal nerve branched from the right vagus nerve and hooked around the right-sided aortic arch., Conclusions: Right lobectomy with mediastinal lymph node dissection under uniportal VATS can be performed for lung cancer in patients with a right-sided aortic arch., (© 2024. The Author(s).)

Background: The fascial anatomy of the anterior mediastinum has not been thoroughly investigated. Only the sternopericardial ligament (SPL) has been defined and is often described as two independent tendons. However, these descriptions differ from our observations of thoracic surgery. Here, we aimed to precisely investigate the fascial anatomy, particularly the SPL, of the anterior mediastinum., Methods: We surgically and radiologically observed and analyzed the fascial anatomy of the anterior mediastinum in patients who underwent surgery for anterior mediastinal disease at our institution between July 2009 and August 2018., Results: A total of 55 thoracoscopic surgeries were performed. We observed a sagittal layer of fibrous tissue bridging the pericardium and sternum, in addition to the well-known fascial layers. Behind the lower bifurcation of the thymic glands, the thymic capsule was firmly fixed to the pericardium around the anterior aortopulmonary trunk. It thickened locally, formed a small white stripe, and occasionally deformed the pericardium by pulling it anteriorly. No other tendon-like structure was observed., Conclusions: Our observation of the SPL showed differences from classical descriptions. The SPL is a sagittal fibrous collection showing a unique figure. Part of the SPL is thickened behind the thymus, anchoring the thymus to the pericardium in the midline. The SPL is part of the bottom of Grodinsky's Space 3 in the thorax. The SPL is visible in radiologic images, such as the anterior junction line on a plain chest radiograph., Competing Interests: Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1602/coif). The authors have no conflicts of interest to declare., (2024 Journal of Thoracic Disease. All rights reserved.)

The structural and superconducting properties of the Bi-based compound Bi 2 Pd 3 Se 2 were investigated over a wide pressure range. The prepared Bi 2 Pd 3 Se 2 sample was a superconductor with a superconducting transition temperature, T c , of approximately 3.0 K, which differed from a previous report ( T c of less than 1.0 K). At ambient pressure, the powder X-ray diffraction (XRD) pattern of the Bi 2 Pd 3 Se 2 sample was consistent with that previously reported for Bi 2 Pd 3 Se 2 . The Rietveld method was used to refine the crystal structure, which had a space group of C 2/ m (No. 12), as reported previously. This compound showed no clear anomaly due to the charge-density-wave (CDW) transition, as seen from the temperature dependence of magnetic susceptibility. However, the temperature dependence of electrical resistivity indicated a clear anomaly, presumably because of the CDW transition in the low-pressure range; the CDW transition temperature was approximately 230 K. The XRD patterns of the Bi 2 Pd 3 Se 2 sample were measured at 0.160-22.7 GPa, and the patterns were well analyzed by both the Le Bail and Rietveld refinement methods, showing no structural phase transitions in the above pressure range. The pressure dependence of T c of Bi 2 Pd 3 Se 2 was recorded based on the temperature dependence of the electrical resistance, which showed an almost constant T c at 0-13.7 GPa, and the T c -pressure ( p ) behavior was fully discussed.

Fe 5- x GeTe 2 is a two-dimensional van der Waals material that exhibits ferromagnetic order with a high Curie temperature ( T C ) of around room temperature. In addition to T C , two magnetic transitions occur with decreasing temperature, and a charge-ordered state is observed at low temperatures. We employed Ge Kα X-ray fluorescence holography (XFH) for Fe 5- x GeTe 2 to directly investigate the local structure in the charge-ordered state, i.e., the 3 × 3 superstructure. The Ge Kα XFH results revealed local atomic structures around the Ge atom, thus clarifying the simultaneous locations and arrangements of the Te, Fe, and Ge atoms. The atomic positions relative to the Ge atom are useful for understanding the coexistence of the ideal 1 × 1 structure and 3 × 3 superstructure found in the charge-ordered state.

A graphite-like material boron carbide (BC x ) was synthesized under various heat treatment conditions and extensively characterized. First, we synthesized the BC x precursor phase by a single-step reaction using a mixed solution of BBr 3 and C 6 H 6 . We confirmed that the precursor phase had a graphite-like structure with B-C chemical bonds, but its crystallinity was poor. To improve their crystallinity, we annealed the precursor sample at high temperature using a high-frequency furnace and determined the annealing condition. We also investigated the magnetic properties of BC x . The high-temperature annealing for the precursor phase yields the highest Pauli paramagnetic susceptibility χ Pauli , indicating the highest density of states at the Fermi level. Accordingly, the high-temperature treatment for the precursor phase is significant to improve its crystallinity and physical properties. In addition, we synthesized a Ti-intercalated material TiBC by using the same procedure as that for making the BC x precursor phase. The crystal structure can be indexed by the AlB 2 structure, indicating that Ti atoms are intercalated between the BC layers. The χ Pauli value of TiBC is obtained to be 1 order of magnitude smaller than that of BC x , suggesting the compensation of hole carriers by electron doping through Ti intercalation into the BC x system.

Background: The minimally invasive nature of thoracoscopic surgery is well recognized; however, the absence of a reliable evaluation method remains challenging. We hypothesized that the postoperative recovery speed is closely linked to surgical invasiveness, where recovery signifies the patient's behavior transition back to their preoperative state during the perioperative period., Objective: This study aims to determine whether machine learning using triaxial acceleration data can effectively capture perioperative behavior changes and establish a quantitative index for quantifying variations in surgical invasiveness., Methods: We trained 7 distinct machine learning models using a publicly available human acceleration data set as supervised data. The 3 top-performing models were selected to predict patient actions, as determined by the Matthews correlation coefficient scores. Two patients who underwent different levels of invasive thoracoscopic surgery were selected as participants. Acceleration data were collected via chest sensors for 8 hours during the preoperative and postoperative hospitalization days. These data were categorized into 4 actions (walking, standing, sitting, and lying down) using the selected models. The actions predicted by the model with intermediate results were adopted as the actions of the participants. The daily appearance probability was calculated for each action. The 2 differences between 2 appearance probabilities (sitting vs standing and lying down vs walking) were calculated using 2 coordinates on the x- and y-axes. A 2D vector composed of coordinate values was defined as the index of behavior pattern (iBP) for the day. All daily iBPs were graphed, and the enclosed area and distance between points were calculated and compared between participants to assess the relationship between changes in the indices and invasiveness., Results: Patients 1 and 2 underwent lung lobectomy and incisional tumor biopsy, respectively. The selected predictive model was a light-gradient boosting model (mean Matthews correlation coefficient 0.98, SD 0.0027; accuracy: 0.98). The acceleration data yielded 548,466 points for patient 1 and 466,407 points for patient 2. The iBPs of patient 1 were [(0.32, 0.19), (-0.098, 0.46), (-0.15, 0.13), (-0.049, 0.22)] and those of patient 2 were [(0.55, 0.30), (0.77, 0.21), (0.60, 0.25), (0.61, 0.31)]. The enclosed areas were 0.077 and 0.0036 for patients 1 and 2, respectively. Notably, the distances for patient 1 were greater than those for patient 2 ({0.44, 0.46, 0.37, 0.26} vs {0.23, 0.0065, 0.059}; P=.03 [Mann-Whitney U test])., Conclusions: The selected machine learning model effectively predicted the actions of the surgical patients with high accuracy. The temporal distribution of action times revealed changes in behavior patterns during the perioperative phase. The proposed index may facilitate the recognition and visualization of perioperative changes in patients and differences in surgical invasiveness., (©Kozo Nakanishi, Hidenori Goto. Originally published in JMIR Perioperative Medicine (http://periop.jmir.org), 14.11.2023.)

The structural and superconducting properties of a Bi-based compound, Bi 2 Rh 3 Se 2 , are investigated over a wide pressure range. Bi 2 Rh 3 Se 2 is a superconductor with a superconducting transition temperature, T c , of 0.7 K. This compound is in a charge-density-wave (CDW) state below 240 K, which implies the coexistence of superconducting and CDW states at low temperatures. Here, the superconducting properties of Bi 2 Rh 3 Se 2 are studied from the perspective of the temperature dependence of electrical resistance ( R ) at high pressures ( p 's). The pressure dependence of T c of Bi 2 Rh 3 Se 2 shows a slow increase in T c at 0-15.5 GPa, and the T c slowly decreases with pressure above 15.5 GPa, which is markedly different from that of normal superconductors because the value of T c should simply decrease owing to the decrease in density of states (DOS) on the Fermi level, N (ε F ), driven by a simple shrinkage of the lattice under pressure. To ascertain the origin of such a dome-like T c - p behavior, the crystal structure of Bi 2 Rh 3 Se 2 was explored over a wide pressure range of 0-20 GPa on the basis of powder X-ray diffraction; no structural phase transitions or simple shrinkage of the lattice was observed. This result implies that the increase in T c against pressure cannot simply be explained from a structural point of view. In other words, a direct relation between superconductivity and crystal structure was not found. On the other hand, the CDW transition became ambiguous at pressures higher than 3.8 GPa, suggesting that the T c had been suppressed by the CDW transition in a low pressure range. Thus, the findings suggest that for Bi 2 Rh 3 Se 2 , T c is enhanced through the suppression of CDW transition, which may be reasonable because the CDW-ordered state restrains the charge fluctuation to weaken the electron-phonon coupling and opens the gap to decrease the density of states on the Fermi level. The obtained dome-like T c - p behavior indicates the possibility of Bi 2 Rh 3 Se 2 being an exotic superconductor.

Doping a typical topological insulator, Bi 2 Se 3 , with Ag impurity causes a semiconductor-metal (S-M) transition at 35 K. To deepen the understanding of this phenomenon, structural and transport properties of Ag-doped Bi 2 Se 3 were studied. Single-crystal X-ray diffraction (SC-XRD) showed no structural transitions but slight shrinkage of the lattice, indicating no structural origin of the transition. To better understand electronic properties of Ag-doped Bi 2 Se 3 , extended analyses of Hall effect and electric-field effect were carried out. Hall effect measurements revealed that the reduction of resistance was accompanied by increases in not only carrier density but carrier mobility. The field-effect mobility is different for positive and negative gate voltages, indicating that the E F is located at around the bottom of the bulk conduction band (BCB) and that the carrier mobility in the bulk is larger than that at the bottom surface at all temperatures. The pinning of the E F at the BCB is found to be a key issue to induce the S-M transition, because the transition can be caused by depinning of the E F or the crossover between the bulk and the top surface transport., (© 2023. The Author(s).)

The crystal structure and superconducting properties of a new type of titanium-pnictide superconductor, BaTi 2 (Sb 1- y Bi y ) 2 O ( y = 0.2, 0.5, and 0.8), are comprehensively investigated over a wide pressure range to elucidate the effect of substituting Bi for Sb on the superconducting behavior. The behavior of superconducting properties under pressure changes drastically with y , as expected from the double-dome T c - y phase diagram obtained at ambient pressure. In this study, three BaTi 2 (Sb 1- y Bi y ) 2 O samples ( y = 0.2, 0.5, and 0.8) are considered, which correspond to the first superconducting dome, nonsuperconducting part, and second superconducting dome, respectively, in the T c - y phase diagram. The crystal of BaTi 2 (Sb 1- y Bi y ) 2 O with y = 0.2 shows a clear collapse transition, i.e., a drastic shrinkage of the lattice constant c at ca. 5 GPa. Strictly speaking, the collapsed crystal phase coexists with the noncollapsed phase above 5 GPa. On the other hand, BaTi 2 (Sb 1- y Bi y ) 2 O with y = 0.8 shows a continuous change in the crystal lattice with pressure, i.e., no collapse transitions. The pressure dependence of T c for BaTi 2 (Sb 1- y Bi y ) 2 O with y = 0.2 shows a drastic increase in T c at approximately 5 GPa, where the collapse transition occurs, indicating a clear pressure-induced superconducting phase transition related to the collapse transition. The value of T c for BaTi 2 (Sb 1- y Bi y ) 2 O with y = 0.8 increases slightly up to ∼2 GPa and is almost constant at 2-13 GPa. It is found that the superconducting behavior under pressure can be unambiguously classified by y based on the double-dome T c - y phase diagram, indicative of distinguishable superconducting features at different y values. In this study, we comprehensively discuss the superconducting properties of the exotic material, BaTi 2 (Sb 1- y Bi y ) 2 O, with a double-dome T c - y phase diagram.

Background: Immune checkpoint inhibitors (ICIs) have become central to lung cancer drug therapy, and establishing biomarkers that can predict effects and adverse events (AEs) is awaited. We prospectively analyzed the association between the immune-related molecular expression in peripheral blood mononuclear cells (PBMCs) and lung cancer tissues, and the effects of ICI monotherapy., Methods: Twenty-one patients with advanced non-small cell lung cancer (NSCLC) who received ICI monotherapy were included. Changes in the expression of immune-related molecules in PBMCs before and after the administration of ICI were analyzed by flow cytometry. The major histocompatibility complex (MHC) class I and programmed cell death-ligand 1 (PD-L1) expression of cancer cells, and the PD-L1, CD8 and CD103 expression of tumor infiltrating immune cells in lung cancer tissue before the administration of ICI were confirmed by immunohistochemistry (IHC)., Results: Twenty-one patients were investigated, including 11 adenocarcinoma and 10 squamous cell carcinoma cases. Anti-programmed cell death protein-1 (PD-1) antibody (n=18) and anti-PD-L1 antibody (n=3) were administered. The clinical responses were graded as follows: complete response (CR) (n=1), partial response (PR) (n=7), stable disease (SD) (n=10) and progressive disease (PD) (n=3). Among immune-related molecules expressed in PBMCs, the CD103 + CD39 + CD8 + T cell change after administration closely correlated with the clinical response. In the univariate analyses of the factors associated with progression-free survival (PFS), CD103 + CD39 + CD8 + cell change after administration was identified as a significant prognostic factor, while the CD103 + CD39 + CD8 + cell change after administration and Brinkman index were independent prognostic factors in a multivariate analysis of the factors associated with PFS., Conclusions: The CD103 + CD39 + CD8 + cell change after administration may predict the efficacy of ICIs., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-22-421/coif). The authors have no conflicts of interest to declare., (2022 Translational Lung Cancer Research. All rights reserved.)

Background: In video-assisted thoracoscopic surgery for spontaneous pneumothorax, the initial trocar can be inserted into the pleurocutaneous fistula formed during preoperative chest drain placement. The use of an optical-access trocar to replace the initial trocar and chest tube may have a greater success rate than blind trocar insertion. Therefore, the present study aimed to evaluate the safety and feasibility of the use of an optical-access trocar to replace the initial trocar and chest tube during surgery for spontaneous pneumothorax., Methods: The present study included 28 patients who underwent video-assisted thoracoscopic surgery for spontaneous pneumothorax following preoperative chest drain placement between April, 2017 and December, 2019. At the start of surgery, the chest drain was removed and the initial trocar was inserted into the pleural cavity. An optical-access trocar with an inner diameter of 5 mm was used as the initial trocar. To use a 0-degree endoscope for the optical-access trocar, this procedure requires the preparation of both, a 0-degree endoscope and a 30-degree endoscope. To evaluate the safety of the optical view method, the lungs and chest wall adjacent to the initial trocar insertion site were observed from the second trocar., Results: The initial trocar could be inserted through the chest tube insertion site in 26 out of 28 cases (92.9%). No instances of lung injury or pulsatile bleeding around the initial trocar were observed. No cases of postoperative wound infection or wound dehiscence were observed., Conclusions: The use an optical-access trocar as the initial trocar when replacing a preoperatively placed chest tube is safe and feasible during video-assisted thoracoscopic surgery for spontaneous pneumothorax., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-22-489/coif). The authors have no conflicts of interest to declare., (2022 Journal of Thoracic Disease. All rights reserved.)

The structural and superconducting properties of alkali-Bi-based compounds, KBi 2 and RbBi 2 , were investigated over a wide pressure range for the first time. The samples of KBi 2 and RbBi 2 were prepared using a liquid ammonia (NH 3 ) technique, and demonstrated superconductivity with superconducting transition temperatures, T c , of 3.50 and 4.21 K at ambient pressure, respectively. The onset superconducting transition temperature, T c onset , of KBi 2 decreased slightly; however, it suddenly jumped at 2 GPa and increased gradually with pressure, indicating the presence of two superconducting phases in the low-pressure range. The pressure-dependent X-ray diffraction patterns indicate that the KBi 2 sample decomposed into KBi and Bi at pressures higher than 2.5 GPa. Moreover, a discontinuous change in T c onset was observed for KBi 2 at 9 GPa, which reflects the decomposition of KBi 2 into KBi and Bi. By contrast, the value of T c onset of RbBi 2 was almost constant over a pressure range of 0-8 GPa. Thus, the superconducting properties and stability of alkali-Bi-based compounds against pressure were comprehensively explored in this study. In addition, the superconducting Cooper pair symmetry was investigated from the magnetic field dependence of T c of KBi 2 at 0.790 and 2.32 GPa, and of RbBi 2 at 1.17 GPa, indicating the exact deviation from the simple s -wave paring model, which may be due to the complex electronic structure of Bi. The results elucidated the exotic superconducting properties of KBi 2 and RbBi 2 based on the pressure and magnetic field dependence of T c and verified the chemical stability of KBi 2 under pressure.

The magnitude of the field-effect mobility μ of organic thin-film and single-crystal field-effect transistors (FETs) has been overestimated in certain recent studies. These reports set alarm bells ringing in the research field of organic electronics. Herein, we report a precise evaluation of the μ values using the effective field-effect mobility, μ eff , a new indicator that is recently designed to prevent the FET performance of thin-film and single-crystal FETs based on various phenacene molecules from being overestimated. The transfer curves of a range of FETs based on phenacene are carefully categorized on the basis of a previous report. The exact evaluation of the value of μ eff depends on the exact classification of each transfer curve. The transfer curves of all our phenacene FETs could be successfully classified based on the method indicated in the aforementioned report, which made it possible to evaluate the exact value of μ eff for each FET. The FET performance based on the values of μ eff obtained in this study is discussed in detail. In particular, the μ eff values of single-crystal FETs are almost consistent with the μ values that were reported previously, but the μ eff values of thin-film FETs were much lower than those previously reported for μ, owing to a high absolute threshold voltage, | V th |. The increase in the field-effect mobility as a function of the number of benzene rings, which was previously demonstrated based on the μ values of single-crystal FETs with phenacene molecules, is well reproduced from the μ eff values. The FET performance is discussed based on the newly evaluated μ eff values, and the future prospects of using phenacene molecules in FET devices are demonstrated., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Background: Previously, we identified the highly immunogenic cancer testicular antigen named Kita-Kyushu Lung Cancer antigen-1 (KK-LC-1). In this study, we analyzed the effect of KK-LC-1 expression on the prognosis of patients with resected squamous cell lung cancer., Methods: Fifty squamous cell lung cancer patients, who received complete resection, were enrolled in this study. The expressions of KK-LC-1, CD8, human leukocyte antigen (HLA) class I, and programmed cell death protein ligand-1 (PD-L1) were assessed via immunohistochemistry staining using the specimens obtained from the participants. The association between the expression of the abovementioned molecules and patient prognosis was investigated., Results: KK-LC-1 expression was observed in 21 of 50 recruited cases (42%). However, no significant correlation was found between KK-LC-1 expression and patient prognosis. The prognosis was significantly better in lung cancer cases with KK-LC-1 expression in which CD8 + T cells infiltrated the tumor. Regardless of the HLA class I expression or the PD-L1 expression, the KK-LC-1 expression in squamous cell lung cancer could not be detected as a significant prognostic factor. Furthermore, considering the polarity of the cancer tissue as epithelium, staining of KK-LC-1 tended to be strong in the area corresponding to the basal side of the tumor tissue. The Ki-67 expression was frequently observed in cancer cells on the basal side, which was consistent with the KK-LC-1 expression in representative four cases with KK-LC-1-positive squamous cell lung cancer., Conclusions: Our results indicated that lung squamous cell cancer patients with KK-LC-1 expression and the tumor infiltrating CD8 + T cells might exhibit better prognosis. KK-LC-1 might be highly expressed in cancer cells with high proliferative capacity. Larger cohort analysis is still required for further elucidation and validation of the results of this study., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://dx.doi.org/10.21037/tcr-21-1581). The authors have no conflicts of interest to declare., (2021 Translational Cancer Research. All rights reserved.)

Herein, we report the preparation and characterization of BaBi 3 clarified by DC magnetic susceptibility, powder X-ray diffraction (XRD), and electrical transport. The superconducting properties of BaBi 3 were elucidated through the magnetic and electrical transport properties in a wide pressure range. The superconducting transition temperature, T c , showed a slight decrease (or almost constant T c ) against pressure up to 17.2 GPa. The values of the upper critical field, H c2 , at 0 K, were determined to be 1.27 T at 0 GPa and 3.11 T at 2.30 GPa, using the formula, because p -wave pairing appeared to occur for this material at both pressures, indicating the unconventionality of superconductivity. This result appears to be consistent with the topological non-trivial nature of superconductivity predicted theoretically. The pressure-dependent XRD patterns measured at 0-20.1 GPa indicated no structural phase transitions up to 20.1 GPa, i.e. , the structural phase transitions from the α phase to the β or γ phase which are induced by an application of pressure were not observed, contrary to the previous report, demonstrating that the α phase is maintained over the entire pressure range. Admittedly, the lattice constants and the volume of the unit cell, V , steadily decrease with increasing pressure up to 20.1 GPa. In this study, the plots of T c versus p and V versus p of BaBi 3 are depicted over a wide pressure range for the first time.

The crystal structures of Sb 2 Te 3- y Se y ( y = 0.6 and y = 1.2) at 0-24 GPa were investigated by synchrotron x-ray diffraction. The stoichiometry of Sb 2 Te 3- y Se y used in this study was determined to be Sb 2 Te 2.19(9) Se 0.7(2) for y = 0.6 and Sb 2 Te 1.7(1) Se 1.3(3) for y = 1.2, on the basis of energy-dispersive x-ray spectroscopy. The sample of Sb 2 Te 2.19(9) Se 0.7(2) showed a structural phase transition from a rhombohedral structure (space group No. 166, R 3¯ m ) (phase I) to a monoclinic structure (space group No. 12, C 2/ m ) (phase II), with increasing pressure up to ∼9 GPa. A new structural phase (phase II') emerged at 17.7 GPa, a monoclinic structure with the space group C 2/ c (No. 15). Finally, a 9/10-fold monoclinic structure (space group No. 12, C 2/ m ) (phase III) was observed at 21.8 GPa. In contrast, the sample of Sb 2 Te 1.7(1) Se 1.3(3) provided only phase I (space group No. 166, R 3¯ m ) and phase II (space group No. 12, C 2/ m ), showing one structural phase transition from 0-19.5 GPa. These samples were not superconductors at ambient pressure, but superconductivity suddenly appeared with increasing pressure. Superconductivity with superconducting transition temperatures ( T c 's) of 2 and 4 K was observed above 6 GPa in phase I of Sb 2 Te 2.19(9) Se 0.7(2) . In this sample, the T c values of 6 and 9 K were observed in phase II and phase II' or III of Sb 2 Te 2.19(9) Se 0.7(2) , respectively. Superconductivity with T c 's of 4 and 5 K suddenly emerged in Sb 2 Te 1.7(1) Se 1.3(3) at 13.6 GPa, which corresponds to phase II, and it evolved to 6.0 K under further increased pressure. A T c value of 9 K was finally found above 15 GPa. The magnetic field dependence of T c in phase II of Sb 2 Te 2.19(9) Se 0.7(2) and Sb 2 Te 1.7(1) Se 1.3(3) followed a p -wave polar model, suggesting topologically nontrivial superconductivity., (© 2021 IOP Publishing Ltd.)