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Abstract 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.

Abstract Doping a typical topological insulator, Bi2Se3, 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 Bi2Se3 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 Bi2Se3, 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.

BackgroundThe 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. ObjectiveThis 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. MethodsWe 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. ResultsPatients 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]). ConclusionsThe 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.

Abstract Background The prognosis of patients who undergo unilateral pneumonectomy and subsequently develop a contralateral pulmonary tumor can be improved by tumor resection. Thus, surgery is a treatment option if the patient’s pulmonary function and performance status are satisfactory. To date, there have been only few cases reporting thoracoscopic lung resection for pulmonary tumor after contralateral pneumonectomy because of the difficulty in respiratory management during surgery. Thoracoscopic surgery requires the maintenance of the operative field to allow the lung to collapse, and in partial lung resection we need to identify tumor localization. The identification of a tumor lesion just inferior to the pleura is easy; however, the identification of a tumor lesion in the deep parts is difficult. The tumor in the deep part of the lung segments can be easily located if the tumor-affected lobe is allowed to completely collapse. Therefore, ventilation technique should be modified according to the tumor localization. Case presentation Here, we report three cases of thoracoscopic partial lung resections for pulmonary tumors that developed after contralateral pneumonectomy. Intermittent manual ventilation using a tracheal tube was performed in two cases with a lesion just inferior of the pleura. The tumors in both patients were resected using automatic suturing devices while arresting manual ventilation. The affected lobe was allowed to collapse using a bronchial blocker in one of the cases with a lesion in the deep part. Furthermore, she had contralateral pneumothorax with bullae on the right upper and lower lobes of the lung. The tumor in the deep part of the lung segment and ruptured bullae were easily located and resected using automatic suturing devices. The hemodynamic status of the patients was stable, and the intra- and postoperative courses were uneventful. Conclusions Our cases demonstrate that thoracoscopic lung resection after contralateral pneumonectomy can be performed if intermittent manual ventilation is utilized when the tumor is located just inferior to the pleura and if selective double ventilation using an intrabronchial blocker is utilized when the tumor is located in the deep part.

Abstract We have produced a superconducting binary-elements intercalated graphite, CaxSr1−xCy, with the intercalation of Sr and Ca in highly-oriented pyrolytic graphite; the superconducting transition temperature, T c, was ~3 K. The superconducting CaxSr1−xCy sample was fabricated with the nominal x value of 0.8, i.e., Ca0.8Sr0.2Cy. Energy dispersive X-ray (EDX) spectroscopy provided the stoichiometry of Ca0.5(2)Sr0.5(2)Cy for this sample, and the X-ray powder diffraction (XRD) pattern showed that Ca0.5(2)Sr0.5(2)Cy took the SrC6-type hexagonal-structure rather than CaC6-type rhombohedral-structure. Consequently, the chemical formula of CaxSr1−xCy sample could be expressed as ‘Ca0.5(2)Sr0.5(2)C6’. The XRD pattern of Ca0.5(2)Sr0.5(2)C6 was measured at 0–31 GPa, showing that the lattice shrank monotonically with increasing pressure up to 8.6 GPa, with the structural phase transition occurring above 8.6 GPa. The pressure dependence of T c was determined from the DC magnetic susceptibility and resistance up to 15 GPa, which exhibited a positive pressure dependence of T c up to 8.3 GPa, as in YbC6, SrC6, KC8, CaC6 and Ca0.6K0.4C8. The further application of pressure caused the rapid decrease of T c. In this study, the fabrication and superconducting properties of new binary-elements intercalated graphite, CaxSr1−xCy, are fully investigated, and suitable combinations of elements are suggested for binary-elements intercalated graphite.

Abstract Background We report a case of napsin A-positive metastatic lung cancer originating from the colon. No cases of napsin A-positive metastatic lung tumors originating from colorectal cancer have been reported previously. Case presentation Computed tomography identified a small lung nodule in a 70-year-old male patient, 18 months after resection for rectal cancer. The size of the lung tumor increased from 1.8 to 2.1 cm in 6 months and metastasis from the rectal cancer was suspected. Resection of the lung tumor was performed, and the histological features of the lung tumor revealed findings typical of colorectal adenocarcinoma and resembled those of the original rectal cancer. Furthermore, the metastasis stained positive for napsin A and thyroid transcription factor-1 (TTF-1) on immunohistochemical evaluation, and immunohistochemical analysis identified the same results in the rectal specimen. Conclusions These findings led us to believe that this was a rare case of napsin A-positive metastatic lung cancer originating in the colon. The patient was treated with chemotherapy for recurrent rectal cancer, and no other metastases were found after the lung resection. This is the first report of napsin A-positive colorectal cancer metastasizing to the lung.

We investigated the temperature dependence of resistivity in thin crystals of FeSe _1−x Te _x (x = 1.0, 0.95, and 0.9), though bulk crystals with 1.0 ≧ × ≧ 0.9 are known to be non-superconducting. With decreasing thickness of the crystals, the resistivity of x = 0.95 and 0.9 decreases and reaches zero at a low temperature, which indicates a clear superconducting transition. The anomaly of resistivity related to the structural and magnetic transitions completely disappears in 55- to 155-nm-thick crystals of x = 0.9, resulting in metallic behavior in the normal state. Microbeam x-ray diffraction measurements were performed on bulk single crystals and thin crystals of FeSe _1−x Te _x . A significant difference of the lattice constant, c , was observed in FeSe _1−x Te _x , which varied with differing Te content (x), and even in crystals with the same x, which was mainly caused by inhomogeneity of the Se/Te distribution. It has been found that the characteristic temperatures causing the structural and magnetic transition ( T _t ), the superconducting transition ( T _c ), and the zero resistivity ( T _c ^zero ) are closely related to the value of c in thin crystals of FeSe _1−x Te _x .

We prepared two superconducting phases of (NH _3 ) _y Li _x FeSe _0.5 Te _0.5 , which show superconducting transition temperatures ( T _c ’s) as high as 20.2 and 29.5 K at ambient pressure, here called the ‘low- T _c phase’ and ‘high- T _c phase’. The temperature dependence of electrical resistance ( R ) was measured for the low- T _c phase of (NH _3 ) _y Li _x FeSe _0.5 Te _0.5 over a pressure ( p ) range of 0–14 GPa, and for the high- T _c phase of (NH _3 ) _y Li _x FeSe _0.5 Te _0.5 over 0–19 GPa, yielding double-dome superconducting T _c – p phase diagrams, i.e. two superconducting phases (SC-I and SC-II) were found for both the low- T _c and high- T _c phases under pressure. For the low- T _c phase, the maximum T _c was 20.2 K at 0 GPa for SC-I, and 19.9 K at 8.98 GPa for SC-II. For the high- T _c phase, the maximum T _c was 33.0 K at 1.00 GPa for SC-I, and 24.0 K at 11.5–13.2 GPa for SC-II. These results imply that the maximum T _c value of the high pressure phase (SC-II) does not exceed the maximum value of the SC-I, unlike what was shown in the T _c – p phase diagrams of (NH _3 ) _y Li _x FeSe and (NH _3 ) _y Cs _x FeSe investigated previously. Nevertheless, the double-dome T _c – p phase diagram was found in metal-doped FeSe _0.5 Te _0.5 , indicating that this feature is universal in metal-doped FeSe _1− _z Te _z . Moreover, no structural phase transitions were observed for either the low- T _c or high- T _c phases of (NH _3 ) _y Li _x FeSe _0.5 Te _0.5 over the wide pressure range of 0–15.3 GPa, and the T _c -lattice constant ( c ) plots for both phases were recorded to determine the critical point separating SC-I and SC-II.

This is a prospective clinical study aimed at introducing a method to visualise the location of an air leak and to identify the bulla responsible on three-dimensional (3-D) cine CT. In 10 patients with spontaneous pneumothorax, dynamic 320-detector row CT was performed with injection of 0.9% saline into the affected pleural cavity via a preplaced chest tube. In eight cases, 3-D cine CT thoracography revealed the location of the air leak and the bulla responsible (7 cases: air stream sign; 1 case: repeated collapse and expansion of a bulla with the patient's breathing). [ABSTRACT FROM AUTHOR]

Electrostatic carrier-doping is attracting serious attention as a meaningful technique for producing interesting electronic states in two-dimensional (2D) layered materials. Ionic-liquid gating can provide the critical carrier density required to induce the metal-insulator transition and superconductivity. However, the physical properties of only a few materials have been controlled by the electrostatic carrier-doping during the past decade. Here, we report an observation of superconductivity in a 2D layered material, LaOBiS2, achieved by the electrostatic electron-doping. The electron doping of LaOBiS2 induced metallic conductivity in the normally insulating LaOBiS2, ultimately led to superconductivity. The superconducting transition temperature, TC, was 3.6 K, higher than the 2.7K seen in LaO1-xFxBiS2 with an electron-doped BiS2 layer. A rapid drop in resistance (R) was observed at low temperature, which disappeared with the application of high magnetic fields, implying a superconducting state. This study reveals that electrondoping is an important technique for inducing superconductivity in 2D layered BiS2 materials. [ABSTRACT FROM AUTHOR]

A new superconducting sample, Ba1−xCsxTi2Sb2O, was prepared and characterized in a wide pressure range. The maximum value of superconducting transition temperature, Tc, of Ba1−xCsxTi2Sb2O was 4.4 K for x = 0.25 at ambient pressure. The crystal structure was determined to be tetragonal [space group of P4/mmm (No. 123)]. The charge density wave/spin density wave transition was observed at 44 K for Ba1−xCsxTi2Sb2O (nominal x = 0.25) at ambient pressure, but the transition was suppressed by applying pressure. The pressure dependent X-ray diffraction showed no structural phase transition up to 23.4 GPa, but very interesting Tc–pressure (p) behavior was observed, i.e. the Tc decreases with an increase in pressure up to 4.0 GPa, but it increased above 4.0 GPa, suggestive of non-BCS type behavior. Thus, the systematic study on new pnictide superconductor, Ba1−xCsxTi2Sb2O, was achieved, and the fascinating behavior of superconductivity against pressure was discovered. [ABSTRACT FROM AUTHOR]

Electrostatic carrier-doping is attracting serious attention as a meaningful technique for producing interesting electronic states in two-dimensional (2D) layered materials. Ionic-liquid gating can provide the critical carrier density required to induce the metal-insulator transition and superconductivity. However, the physical properties of only a few materials have been controlled by the electrostatic carrier-doping during the past decade. Here, we report an observation of superconductivity in a 2D layered material, LaOBiS2, achieved by the electrostatic electron-doping. The electron doping of LaOBiS2 induced metallic conductivity in the normally insulating LaOBiS2, ultimately led to superconductivity. The superconducting transition temperature, TC, was 3.6 K, higher than the 2.7K seen in LaO1-xFxBiS2 with an electron-doped BiS2 layer. A rapid drop in resistance (R) was observed at low temperature, which disappeared with the application of high magnetic fields, implying a superconducting state. This study reveals that electrondoping is an important technique for inducing superconductivity in 2D layered BiS2 materials. [ABSTRACT FROM AUTHOR]

Superconducting phases of (NH3)yMxFeSe1-zTez have been synthesized by the intercalation of metal atoms (M: Li, Na, Ca) into FeSe and FeSe0.5Te0.5 using a low-temperature liquid NH3 technique. The superconducting transition temperature (Tc) is 31.5 K for Na-doped FeSe, and for Li-, Na-, and Ca-doped FeSe0.5Te0.5 it is 26, 22, and 17 K, respectively. The 31.5 K superconducting is the superconducting phase in ammoniated Na-doped FeSe. The Tc is lower than that (onset Tc = 46 K) of the superconducting phase reported previously. The reason why the Tc of this phase is lower is discussed based on the structure. The pressure dependences of Tc in the (NH3)yNa0.5FeSe and (NH3)yNa0.4FeSe0.5Te0.5 samples have been measured and a negative pressure dependence is observed; i.e., a decrease in lattice constant c leads to a decrease in Tc, consistent with the behavior of (NH3)yCs0.4FeSe reported previously by our group. Furthermore, the magnetic behavior of (NH3)yNa0.4FeSe0.5Te0.5 has been fully investigated at different applied magnetic fields (H) to determine the critical magnetic field. This is a successful metal intercalation into FeSe1-zTez (z≠0) and an observation of superconductivity. [ABSTRACT FROM AUTHOR]

Alkali-metal-intercalated FeSe materials, (NH3)yCs0.4FeSe (M: K, Rb, and Cs), have been synthesized using the liquid NH3 technique. (NH3)yCs0.4FeSe shows a superconducting transition temperature (Tc) as high as 31.2 K, which is higher by 3.8 K than the Tc of nonammoniated Cs0.4FeSe. The Tcs of (NH3)yCs0.4FeSe and (NH3)yCs0.4FeSe are almost the same as those of nonammoniated K0.4FeSe and Rb0.4FeSe. The Tc of (NH3)yCs0.4FeSe shows a negative pressure dependence. A clear correlation between Tc and lattice constant c is found for ammoniated metal-intercalated FeSe materials, suggesting a correlation between Fermi-surface nesting and superconductivity. [ABSTRACT FROM AUTHOR]

We have studied new superconductors prepared by metal doping of two-dimensional (2D) layered materials, FeSe and FeSe0.5Te0.5, using ethylenediamine (EDA). The superconducting transition temperatures (Tcs) of metal-doped FeSe and metal-doped FeSe0.5Te0.5, i.e., (EDA)yMxFeSe and (EDA)yMxFeSe0.5Te0.5 (M: Li, Na, and K), were 31-45 K and 19-25 K, respectively. The stoichiometry of each sample was clarified by energy dispersive x-ray (EDX) spectroscopy, and the x-ray powder diffraction pattern indicated a large expansion of lattice constant c, indicating the cointercalation of metal atoms and EDA. The pressure dependence of superconductivity in (EDA)yNaxFeSe0.5Te0.5 has been investigated at a pressure of 0-0.8GPa, showing negative pressure dependence in the same manner as (NH3)yNaxFeSe0.5Te0.5 The Tc-c phase diagrams of MxFeSe and MxFeSe0.5Te0.5 were drawn afresh from the Tc and c of (EDA)yMxFeSe and (EDA)yMxFeSe0.5Te0.5, showing that the Tc increases with increasing c but that extreme expansion of c reverses the Tc trend. [ABSTRACT FROM AUTHOR]

Field-effect transistors (FETs) were fabricated using exfoliated single crystals of Mo(Se1-xTex)2 with an x range of 0 to 1, and the transistor properties fully investigated at 295 K in four-terminal measurement mode. The chemical composition and crystal structure of exfoliated single crystals were identified by energy-dispersive x-ray spectroscopy (EDX), single-crystal x-ray diffraction, and Raman scattering, suggesting the 2H- structure in all Mo(Se1-xTex)2. The lattice constants of a and c increase monotonically with increasing x, indicating the substitution of Se by Te. When x<0.4 in a FET with a thin single crystal of Mo(Se1-xTex)2, n-channel FET properties were observed, changing to p-channel or ambipolar operation for x>0.4. In contrast, the polarity of a thick single-crystal Mo(Se1-xTex)2 FET did not change despite an increase in x. The change of polarity in a thin single-crystal FET was well explained by the variation of electronic structure. The absence of such change in the thick single-crystal FET can be reasonably interpreted based on the large bulk conduction due to naturally accumulated electrons. The μ value in the thin single-crystal FET showed a parabolic variation, with a minimum μ at around x=0.4, which probably originates from the disorder of the single crystal caused by the partial replacement of Se by Te, i.e., a disorder that may be due to ionic size difference of Se and Te. [ABSTRACT FROM AUTHOR]

Na-intercalated FeSe0.5Te0.5 was prepared using the liquid NH3 technique, and a superconducting phase exhibiting a superconducting transition temperature (Tc) as high as 27 K was discovered. This can be called the high-Tc phase since a 21 K superconducting phase was previously obtained in (NH3)yNaxFeSe0.5Te0.5. The chemical composition of the high-Tc phase was determined to be (NH3)0.61(4)Na0.63(5)Fe0.85Se0.55(3)Te0.44(2). The x-ray diffraction patterns of both phases show that a larger lattice constant c (i.e., FeSe0.5Te0.5 plane spacing) produces a higher Tc. This behavior is the same as that of metal-doped FeSe, suggesting that improved Fermi-surface nesting produces the higher Tc. The high-Tc phase converted to the low-Tc phase within several days, indicating that it is a metastable phase. The temperature dependence of resistance for both phases was recorded at different magnetic fields, and the critical fields were determined for both phases. Finally, the Tc versus c phase diagram was prepared for the metal-doped FeSe0.5Te0.5, which is similar to that of metal-doped FeSe, although the Tc is lower. [ABSTRACT FROM AUTHOR]

The superconducting transition temperature Tc of ammoniated metal-doped FeSe (NH3)yMxFeSe (M: metal atom) has been scaled with the FeSe plane spacing, and it has been suggested that the FeSe plane spacing depends on the location of metal atoms in (NH3)yMxFeSe crystals. Although the crystal structure of (NH3)yLixFeSe exhibiting a high Tc (∼44 K) was determined from neutron diffraction, the structure of (NH3)yMxFeSe exhibiting a low Tc (∼32 K) has not been determined thus far. Here, we determined the crystal structure of (NH3)yCs0.4FeSe(Tc=33K) through the Rietveld refinement of the x-ray diffraction (XRD) pattern measured with synchrotron radiation at 30 K. The XRD pattern was analyzed based on two different models, on-center and off-center, under a space group of I4/mmm. In the on-center structure, the Cs occupies the 2a site and the N of NH3 may occupy either the 4c or 2b site, or both. In the off-center structure, the Cs may occupy either the 4c or 2b site, or both, while the N occupies the 2a site. Only an on-center structure model in which the Cs occupies the 2a and the N of NH3 occupies the 4c site provided reasonable results in the Rietveld analysis. Consequently, we concluded that (NH3)yCs0.4FeSe can be assigned to the on-center structure, which produces a smaller FeSe plane spacing leading to the lower Tc. [ABSTRACT FROM AUTHOR]