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Background Although the opportunity to treat subcentimeter lung cancers has increased, the optimal surgical methods remain unclear. We performed a retrospective study to examine the clinical outcome of subcentimeter lung cancers. Patients and Methods In total, 118 patients who underwent curative resection for subcentimeter lung cancer from January 2005 to December 2013 were analyzed. Multivariate Cox proportional hazards models were used to calculate the hazard ratio to identify independent predictors of recurrence-free survival (RFS) and overall survival (OS). Results Anatomical resections were performed for 64 patients (59 lobectomies and 5 segmentectomies) and wedge resections for 54 patients. Recurrence developed in six patients who had consolidation-predominant tumors (consolidation/tumor [C/T] ratio of >0.5) and underwent wedge resections. The first recurrence patterns were regional recurrences in three patients, both regional and distant in one, and distant in two. Seventeen patients died of other causes. The multivariate analysis revealed that the C/T ratio was the independent predictor of RFS (p = 0.008) and OS (p = 0.011). Conclusion Patients with subcentimeter lung cancer rarely developed recurrence. The C/T ratio was the independent prognostic factor, and all relapsed patients received wedge resections. Even for subcentimeter lung cancers, we should select the extent of pulmonary resection after thoroughly considering whether wedge resection (less invasiveness) is a reasonable alternative to anatomical resection (superior oncologic efficacy) considering the C/T ratio of the lesion.

Background/Aim: Vein-first lobectomy (VFL) in lung cancer might reduce shedding of circulating tumour cells (CTCs). This study assessed the clinical significance of VFL. Patients and Methods: Lung cancer patients undergoing lobectomy and CTC testing were evaluated. The primary evaluation item was postoperative clustered CTC detection, and the secondary outcome measures were the 2-year overall survival and recurrence-free survival rates according to the status of VFL and postoperative clustered CTC. Results: Eighty-six patients with similar backgrounds, except for lobe resection and pulmonary vein dissection time, showed postoperative clustered CTC identification rates of 43.8% and 37.9% in the VFL group (n=57) and no-VFL group (n=29), respectively. However, prognosis was not significantly different, although the presence of clustered CTC after surgery was a predictor of recurrence. Conclusion: The status of postoperative clustered CTC was similar regardless of VFL or not, although the detection of clustered CTC was a predictor of recurrence.

Background: Vein-first dissecting lobectomy in lung cancer surgery is speculated to limit the amount of circulating tumor cells. We aimed to assess the clinical significance and prognostic impact of Vein-first dissecting lobectomy according to changes in circulating tumor cell status throughout the perioperative period.Methods: Among patients with pulmonary nodule who underwent surgery, we extracted and evaluated patients who underwent lobectomy for lung cancer and had underwent circulating tumor cell testing before and immediately after the completion of lobectomy. The primary evaluation item was the detection rate of postoperative circulating tumor cell according to the sequence of pulmonary vessel processing. The secondary evaluation items were the 2-year recurrence-free survival and overall survival rates according to the status of Vein-first dissecting lobectomy and postoperative circulating tumor cell. Results: Between June 2014 and June 2018, 302 patients with pulmonary nodule underwent surgery, among them we selected 86 patients who underwent lobectomy for lung cancer and had circulating tumor cell testing done before and immediately after the completion of lobectomy. The circulating tumor cell identification rates in the postoperative period were 54.4% (37/68) and 66.7% (12/18) (p=0.8) in vein-first dissecting lobectomy group and no-vein-first dissecting lobectomy group, respectively. The mean postoperative circulating tumor cell count was not significantly different between the vein-first dissecting lobectomy and no-vein-first dissecting lobectomy groups (3.0 ± 3.6 vs 3.2 ± 5.0, p=0.8). The 2-year recurrence-free survival and overall survival rates were also not significantly different. However, the presence of circulating tumor cell after surgery was a predictor of recurrence.Conclusions: Although the detection of circulating tumor cell after surgery is a predictor of cancer recurrence, no significant difference was observed in the status of postoperative circulating tumor cell s between vein-first dissecting lobectomy and no- vein-first dissecting lobectomy groups in lung cancer surgery.

We developed a computational method for estimating magnetic dipole energy of slab materials using spin density obtained through a density functional approach. The new method can accurately estimate magnetic anisotropy energy (MAE) for slabs from magnetic dipole interaction called shape MAE (SMAE). We investigated ferromagnetic and antiferromagnetic slabs and found that a quadrupole component of atomic spin density suppresses SMAE in ferromagnetic slabs with Fe/MgO interface. In antiferromagnetic MnPt slabs, which have a perpendicular favor originating from the crystalline magnetic dipole interaction, a surface effect at the Mn edge appears as an enhancement of SMAE.

Electric field (EF) control on magnetic anisotropy energy (MAE) in the system which contains Fe/MgO interface with Cr underlayer was performed by means of first-principles electronic structure calculations. An opposite sign in EF coefficient (y) was observed by introducing Fe/Cr intermixing. This intermixing leads to a substantial rearrangement in the electronic structure due to proximity effects of Fe and Cr. The origin of such an opposite sign in y was discussed along with the modulation of occupied and unoccupied d-band near the Fermi level. By introducing a strain effect, the enhancements of MAE and y were achieved with the maximum absolute values, 2.43 mJ/m 2 and 170 fJ/Vm, respectively. The present result provides a new possible degree of freedom for the EF control in MAE as the underlayer configuration.

Background/aim We investigated the relationship between solid component size (SS), carcinoembryonic antigen (CEA), and standardized uptake value (SUVmax) as continuous variables and postoperative clustered circulating tumor cell (C-CTC) detection in patients with pulmonary adenocarcinoma who underwent surgery. Patients and methods C-CTC detection was the main evaluation item, which was analyzed using the receiver operating characteristic curve to calculate areas under the curves (AUCs) for the variables. Additionally, the two-year recurrence-free survival rates (2Y-RFSRs) were analyzed. Results Among the 84 patients examined, SS, CEA, and SUVmax had AUCs>0.7, and were independent. Their thresholds were 2.1 cm, 7.5 ng/ml, and 2.9, respectively. The 2Y-RFSR were significantly better in the non-C-CTC group (n=58) and in the group of patients without high levels of these predictors (n=32). Conclusion SS, CEA level, and SUVmax predicted postoperative CTC detection in pulmonary adenocarcinoma patients.

Single Event Burnout (SEB) is one of the issues causing the blocking instability of high voltage semiconductor devices. In this paper, we suggest introducing Deep N-buffer layer (DN) into IGBT for improvement of the robustness. By TCAD simulation, the destruction mechanism and the effect of the backside structure on SEB robustness were clarified. The result indicated that DN suppressed the temperature rising around P-collector and PNP bipolar action at the backside during the period of the event. The proposed IGBT with DN layer was fabricated and the SEB failure rate was evaluated. The experimental results showed that the proposed structure improved the robustness.

AimsAlthough it is necessary to measure the invasive size of lung adenocarcinoma with a lepidic component, it is not uncommon to have trouble in measuring the invasive size of lung adenocarcinoma. This study examined whether there were other stronger prognostic factors than invasive size.MethodsWe characterised the clinicopathological features associated with recurrence-free survival (RFS) of 686 patients with the pathological stage (p-Stage) I lung adenocarcinoma. Moreover, we compared the area under the curve (AUC) values for recurrence between various combinations of pathological-baseline (age & sex & p-Stage based on invasive size) (B(i)) and several prognostic factors, and various combinations of p-baseline based on total tumour size (B(t)) and several prognostic factors.ResultsAUC showed no significant differences between B(i) & new International Association for the Study of Lung Cancer grade (G) or vascular invasion (V), and B(t) & G or V. AUC was the highest in B & G & lymphatic invasion (L) & V. RFS was significantly shorter in patients with G3 OR L(+) OR V(+) than in those with G≤2 AND L(-) AND V(-) in each p-Stage based on invasive size (p-Stage(i)) and p-Stage based on total tumour size (p-Stage(t)) (pConclusionsIn any invasive size or total tumour size of p-Stage I lung adenocarcinoma, G, L and V are more powerful prognostic factors than the size criteria of p-Stage. Therefore, pathologists should focus on these pathological findings.

The electric control of magnetic anisotropy has important applications for nonvolatile memory and information processing. By first-principles calculations, we show a large nonvolatile control of magnetic anisotropy in the ferromagnetic/ferroelectric CoPt/ZnO interface. Using the switched electric polarization of ZnO, the density-of-states and magnetic anisotropy at the CoPt surface show a large change. Due to a strong Co/Pt orbitals hybridization and a large spin-orbit coupling, a large control of magnetic anisotropy was found. We experimentally measured the change of effective anisotropy by tunneling resistance measurements in CoPt/Mg-doped ZnO/Co junctions. Additionally, we corroborate the origin of the control of magnetic anisotropy by observations on tunneling anisotropic magnetoresistance.

Two-dimensional atomic layer materials with optically transparent materials such as h-BN are expected to be high performance nano-electro-mechanical resonators (NEMR). Elimination of the photothermal effect is very crucial for accurate force sensing using NEMR. Thus, the optically transparent material such as h-BN is one of strong candidates for this purpose. Here, we investigate the photothermal effect on the mechanical resonance properties of the h-BN-NEMR driven by electrostatically using the dielectric effect.

We have been studying the sterilization of bacteria by high electric field pulse. In this paper, we reported the relationship between the size of leaked nucleic acid of Escherichia coli (JM103) and the survival ratio by high electric field pulse application. The sample was NaCl aqueous solution contained E. coli. High electric field pulse (6 kV/mm ~ 10 kV/mm) was applied to the sample at room temperature. As results, at pulse width 600 ns, we could not detect the leakage nucleic acid. At pulse width 60 µs, we could observe the leakage of 2 ~ 3 kbp by 5 kV/mm or more pulse application, and that of 10 kbp by 8 kV/mm or more. At pulse width 120 µs, we could observe the leakage of 2 ~ 3 kbp by 8 kV/mm.

We investigated the magnetic anisotropy energy (MAE) in the free-standing Co/Ni (1 1 1) multilayer as both Ni thickness dependence ( t Ni = 1-4MLs) and number of multilayer repetition times (N = 1–3) by means of a first-principles electronic structure calculation based on spin density functional theory. We included both contributions to the MAE from magnetocrystalline anisotropy energy (MCAE) originating from spin-orbit coupling and shape magnetic anisotropy energy (SMAE) originating from spin dipole-dipole interaction. The MCAE part was evaluated from both methods of total energy (TE) and grand-canonical force theorem (GCFT). The SMAE part was calculated by using a spin density approach (SDA). All MCAE values from the TE are well reproduced by those from the GCFT method. In N = 1, the total MAE (MCAE + SMAE) for t Ni showed a perpendicular MAE (PMAE) with a maximum value of 1.67 mJ/ m 2 at t Ni = 2MLs. The PMAE increases with increasing N. The series of t Ni = 3MLs showed a linear behavior as N dependence with an increasing ratio of 0.68 mJ/ m 2 , which is in good agreement with experimental measurement. By using the GCFT, we evaluated the atom-resolved and k -resolved MCAEs. The atom-resolved MCAE indicates that the Co/Ni interface is the main origin of PMAE. The PMAE is mainly located at Γ ¯ - K ¯ line in the two dimensional Brillouin zone. This is attributed to large components of the d-orbitals extending along the multilayer plane on Co and Ni near the Fermi energy. We also calculated the SMAE using a discrete approach (DA) and found that there is a reduction of SMAE part in the SDA, compared to the DA. This reduction originates from a prolate quadrupole component of spin density distribution. The present comprehensive study may provide a better understanding of magnetic properties in Co/Ni multilayers as widely used in spintronic devices.

Hexagonal boron nitride (h-BN) is an emergent material for single photon emitters that are ultrabright and stable under ambient conditions. To realize h-BN nano-electromechanical resonators (NEMRs) with quantum effects, the oscillation would be electrically controlled without unexpected photothermal effects. This study investigates the mechanical resonance of an optically transparent and electrically insulating h-BN NEMR, which was actuated by an electrostatic force based on the dielectric effect. Under light irradiation, resonance properties show no significant light intensity or wavelength dependence, which indicates that the photothermal effect is well eliminated because of optically transparent h-BN NEMR.

Transition metal dichalcogenide such as MoS 2 is expected as high performance nano-electro-mechanical devices due to their unique electrical, optical and mechanical properties. One can expect that the combination of these properties are efficient to develop the novel functional devices. Here, we demonstrates the amplitude control of resonance characteristics of a cantilevered MoS 2 on the planar substrate, which is actuated by electrostatically. The AC and DC bias voltage dependences of the vibration amplitudes are well explained by the simplified model under linear elastic regime. Moreover, we demonstrate the optical manipulation of the vibration amplitude at the resonance. Under the irradiation of strongly absorbed light by MoS 2 , the vibration amplitude is successfully manipulated by the laser intensity change.

An atomically thin MoS2 field-effect transistor (FET) is expected as an ultrathin photosensor with high sensitivity. However, a persistent photoconductivity phenomenon prevents high-speed photoresponse. Here, we investigate the photoresponse of a MoS2 FET with a thin Al2O3 buffer layer on a SiO2 gate insulator. The application of a 2-nm-thick Al2O3 buffer layer greatly improves not only the steady state properties but also the response speed from 1700 to 0.2 s. These experimental results are well explained by the random localized potential fluctuation model combined with the model based on the recombination of the bounded electrons around the trapped hole.

We carried out the first-principles density functional calculation of the slab systems, MgO(5ML)/Fe(5ML), Fe(5ML)/MgO(5ML)/Fe(5ML), and MgO(3ML)/Fe(3ML)/MgO(1 or 7ML). We investigated structural and electronic properties in the Fe/MgO interface. The slab of a tunnel junction Fe/MgO/Fe exceptionally has a short Fe-O distance and a large Mg displacement from the O layer. In the junction with a small in-plane lattice constant, the interface resonance state tends to shift to a low energy, resulting in a partially electronoccupied state.

We investigated the effect of an electric field on the interface magnetic anisotropy of a thin MgO/Fe/MgO layer using density functional theory. The perpendicular magnetic anisotropy energy (MAE) increases not only under electron depletion but also under some electron accumulation conditions, showing a strong correlation with the number of electrons on the interface Fe atom. The reverse variation in the MAE under the electric field is ascribed to novel features on the charged interface, such as electron leakage. We discuss the origin of the variation in terms of the electronic structures., 11 pages, 4 figures

We investigated the tunneling electroresistance (TER) in metal/wurtzite-MgZnO/metal junctions for applications in nonvolatile random-access memories. A resistive switching was detected utilizing an electric-field cooling at ±1 V and exhibited a TER ratio of 360%–490% at 2 K. The extracted change in the average barrier height between the two resistance states gave an estimation of the MgZnO electric polarization at 2.5 μC/cm2 for the low-temperature limit. In addition, the temperature-dependent TER ratio and the shift of the localized states energies at the barrier interface supported the ferroelectric behavior of the MgZnO tunnel-barrier. From the first-principles calculations, we found a similar effect of the barrier height change coming from the reversal of ZnO electric polarization. The possibility of using metal electrodes and lower growth temperatures, in addition to the ferroelectric property, make the ZnO-based memory devices suitable for CMOS integration.