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Background In laparoscopic gastrointestinal surgery, the location of the tumor is identified mainly with marking methods, such as ink tattooing and intraoperative gastrointestinal endoscopy and marking with a metal clip followed by confirmation with intraoperative x-ray fluoroscopy. Each method has disadvantages, such as complexity, instability of ink sticks, and radiation exposure. Thus, a simple and less-invasive marking method is needed. Methods We developed a wireless light-emitting marker with a miniature light-emitting diode that uses a magnetic field resonance mechanism. It emits 4 individual colors-red, blue, green, and white. We confirmed the usefulness of this marker system in ex vivo and in vivo animal experiments. Results In the ex vivo experiment in porcine intestines, use of the wireless marker was successful, as each color of emitted light was recognized from outside the intestine. In the live animal experiment, it was confirmed that the light emitted by the marker system was visible in the porcine intestinal tract during laparoscopic surgery. The light emitted by the wireless marker in the intestinal tract was confirmed with a laparoscope in a simulated animal surgery. Conclusion We have developed an innovative, radiation-free and reliable light-emitting marker system that uses a magnetic field resonance mechanism that emits four colors of light during laparoscopic surgery.

Background/aim Pancreatic surgery is associated with a high risk of developing deep venous thrombosis (DVT) and malnutrition. We aimed to evaluate the factors predicting the development of DVT, focusing on nutrition assessment tools. Patients and methods One hundred patients who underwent pancreatic surgery were postoperatively examined for DVT. We assessed the risk factors for the development of DVT after surgery. Results Postoperative DVT was detected in 11 patients (11%). Patients who developed DVT after surgery were significantly older (p=0.016) and had higher preoperative D-dimer levels (p=0.005) than those who did not. The preoperative prognostic nutritional index (PNI) was mostly associated with the development of DVT (p=0.079). Furthermore, PNI ≤44.3, BUN >20 mg/dl, D-dimer ≥1.9 μg/ml were independent predictors for the development of DVT after surgery. Conclusion A poor nutrition status and dehydration should be preoperatively improved for patients who are identified, as having a high risk of developing DVT after pancreatic surgery.

Neuroendocrine carcinoma (NEC) of the esophagus and the stomach is aggressive. The purpose of this study was to determine the optimal therapeutic strategy. Both clinicopathological factors and treatment results were examined in 34 patients with immunohistochemically diagnosed NEC of the upper gastrointestinal tract (esophagus 22; stomach 12). Twenty-nine tumors showed protruding and localized type, like submucosal tumor. Esophagectomy and gastrectomy were performed in six and eight patients, respectively. Among the six patients with esophageal NEC, three with node metastasis developed recurrence within seven months, while the other three (pT1bN0) had no recurrence. Regarding gastric NEC, three patients with pT3N1 or 2 tumor received adjuvant chemotherapy and achieved a 5-year survival. However, the other five experienced recurrence after gastrectomy. Systemic chemotherapy was performed as the main treatment for 18 patients with advanced NEC. The median survival was 10 months after initial chemotherapy. No marked differences in the response were recognized between the 14 cases with esophageal NEC and the 4 with gastric NEC. The median survival was 14.3 and 5.3 months for the 11 effective and 7 non-effective patients, respectively. A macroscopically unique appearance, like submucosal tumor, suggests the possibility of NEC. Esophagectomy is an effective treatment option for limited-stage NEC without node metastasis, while gastrectomy followed by adjuvant chemotherapy may be effective for NEC even with node metastasis when R0 resection can be achieved. Systemic chemotherapy is relatively effective for advanced NEC, although early progression frequently develops.

Background/aim The aim of this study was to clarify the treatment strategy for synchronous squamous cell carcinoma of the esophagus (ESCC) and head and neck cancer (HNC). Patients and methods Treatment outcomes of 91 patients with synchronous ESCC and HNC were evaluated. Thirty-eight patients received simultaneous definitive chemoradiotherapy (CRT) and 15 patients underwent simultaneous resection. Results Among the patients who received simultaneous CRT, adverse events (grade 3-5) were recognized in 14 patients (40%), including one case of death due to aspiration pneumonia. Complete response was observed in 22 patients with ESCC (58%) and 19 patients with HNC (50%). The five-year survival rate was 44%. There were no in-hospital deaths after simultaneous resection; however, postoperative complications were recognized in 4 patients. The five-year OS was 70%. Conclusion The treatment of synchronous ESCC and HNC must be decided by adopting a strategy that is appropriate for each case. Both simultaneous CRT and simultaneous resection are feasible and effective treatment options.

Background Neuroendocrine carcinoma (NEC) of the esophagus is a rare and highly aggressive disease; however, an appropriate treatment strategy remains to be established, especially for surgical resection. The objective of this study is to clarify the clinical characteristics of NEC of the esophagus and to determine the optimal surgical strategy. Methods Nineteen patients who were immunohistochemically diagnosed with NEC of the esophagus from 1998 to 2017 were included in this study. The clinical features and therapeutic outcomes were examined. Results 1. Clinical features Sixteen of 19 patients showed protruding or localized type with or without ulceration. Only five patients were negative for both lymph node and organ metastasis and eight cases were positive for metastasis to distant organs and/or distant lymph nodes. 2. Surgical treatment Five patients underwent esophagectomy. Four cases were classified as cStage I (cT1bN0M0); the other case was classified as cStage III (cT3N2M0). The preoperative diagnoses, based on the examination of biopsy specimens, were NEC (n = 2), SCC (n = 1), adenocarcinoma (n = 1), and carcinoma (n = 1). Subtotal and distal esophagostomy were performed in 3 and 2 patients, respectively. Salvage esophagectomy for recurrent disease was performed after definitive chemotherapy in one patient. Anastomotic leakage, which was conservatively healed, developed in one patient. Two patients with histologically-positive node metastasis died at 8 and 13 months, respectively, while another 3 patients (pT1bN0, n = 2; pT2N0, patient, n = 1) are currently alive without any recurrence, at 12, 45 and 72 months after esophagectomy, respectively. 3. Non-surgical treatment Systemic chemotherapy was performed as the main treatment for 13 patients with advanced NEC. The regimens included cisplatin combined with irinotecan or etoposide (n = 10), cisplatin plus 5-fluorouracil (n = 2) and UFT plus irinotecan (n = 1). The MST was 13 months (range, 6–17 months). Conclusion The possibility of NEC should be kept in mind when we encounter protruded tumors of a distinctive shape. Consistent with previous reports, the prognosis of NEC of the esophagus is dismal, irrespective of the administration of systemic chemotherapy. However, surgical resection is considered to be a treatment option for cStage I/II NEC without node metastasis, as a long-term survival after esophagectomy was achieved by some patients. Disclosure All authors have declared no conflicts of interest.

We have studied the Fermi surface and the cyclotron mass of a semimetallic heavy fermion compound YbAs both in the antiferromagnetic state and the paramagnetic state. We have found the Fermi surface of three ellipsoidal electron surfaces and one spherical hole surface, and that the shape of these Fermi surfaces is the same in both states. In addition, we have found that the temperature dependence of the dHvA oscillatory amplitudes change anomalously at the Neel temperature. This anomaly is ascribed to the change of the cyclotron mass and the Dingle temperature at the Neel temperature. To explain the large electronic specific heat coefficient, the extremely heavy hole surface with about 10 3 m 0 should exist.

There have been proposed many phase unwrapping methods, which are roughly divided into two types; (quality guided) path following and least squares. Both types of method, however, do not have enough performance; the former can not unwrap areas having lower quality than residues do, and the latter needs iterative calculation which takes much time. The authors propose a new method that improves the performance both in accuracy and in efficiency. The basic idea of the method is to divide the interferogram into irrotational (residue free) and rotational components. Both components are merged after unwrapping them. A direct residue removing technique is used for getting the irrotational component, and the rotational one is obtained by subtracting the irrotational component from the original interferogram. As it is impossible to unwrap the rotational component, they propose a new algorithm for merging the both components without applying actual unwrapping operation. In this algorithm, positive and negative residues are paired and added to irrotational component sequentially. Virtual residues are used for balancing the numbers of them. As the combination of residues controls the quality of the unwrapped phase, the optimized pairing gives us the minimum L/sup 0/ measure. The performance of the proposed method was confirmed by processing an actual ERS-1 SAR interferogram.

This paper describes a Synthetic Aperture Radar (SAR) phase processing system and an automated method for estimating baseline length and its inclination angle from only pair of Single Look Complex (SLC) images to be interfered. The information about the baseline parameters are indispensable to produce accurate Digital Elevation Model (DEM) without geometrical distortion and also accurate displacement from differential Interferometric SAR (InSAR) processing. Only the nominal value of the baseline length is currently provided. The fixed value, however, does not represent nonparallel orbits from which raw interferogram is obtained. The ambiguity causes the geometrical distortion in DEM and the apparent displacement in the result of differential InSAR processing. In order to produce the accurate DEM, we have to know the baseline parameters as the function of the azimuth line. The proposed method derives coefficients of both functions for baseline length and for inclination angle by fitting the local disparities to a geometrical model. The proposed method was successfully applied to an actual InSAR data. The baseline estimated by the proposed method reduced apparent displacement to 1 /10 of that yielded by the nominal baseline. A piecewise co-registration method is also described for obtaining highly accurate interferogram.

We have newly found and succeeded in growing a mass-enhanced ferromagnet U 2 PtSi 3 . The electronic specific heat coefficient is 200 mJ/K 2 per mole of U. The magnetization shows no saturation up to 80 kOe for both the a - and c -axes. The magnitude of remanence is much smaller compared with the effective moment in the paramagnetic phase. Experimental results on single-crystalline samples are presented and discussed.

A new method, Multiple Phase Method (MPM), is proposed for fast unwrapping InSAR raw interferogram. The unwrapping process is regarded as one of phase adding or subtracting (lifting) processes when 2-pi phase jump is detected. The proposed method MPM distinguishes the phase jump from noise in the raw interferogram by using the original and its pi phase shifted interferograms. MPM removes the phase jump from the lifting operation by switching the difference data from the original interferogram to the phase shifted one or from the shifted one to the original when the phase jump is detected. The phase jump is detected using a simple mask operation. The phase integration is carried out by using new index 'confidence' derived from the coherence as a guide to select the integration path. MPM selects the integration path from higher confidence region to lower ones. As residues have locally minimum coherence, MPM does not pass through them. The proposed method MPM was successfully applied to an actual pair of ERS-1 SAR single look complex images.

dHvA magnetization of U 3 P 4 and YbAs has been measured. The measurement for U 3 P 4 in the {1 1 0} plane shows a new branch. We have observed the dHvA effect in YbAs for the first time. The observed branches consist of ellipsoids of electron sheets. These sheets do not change its shape above and below T N .

The experimental results of the magnetization and specific heat measurements are presented for single crystals of isomorphic U 2 PtSi 3 and U 3 Si 5 . It is shown that U 2 PtSi 3 is a weak itinerant ferromagnet and U 3 Si 5 remains non-magnetic down to about 0.6 K. We also discuss the (de)localization of 5f electrons comparing magnetic properties of other isomorphic compounds.

We have found a new uranium intermetallic compound UPtSi 2 to show ferromagnetic ordering at 86 K. The magnetization has a strong field dependence and reaches a value of 2.6μ B /U at 80 kOe. We present also the temperature dependence of the magnetic susceptibility and the electrical resistivity.

The partial-response maximum-likelihood (PRML) detection technique is effective for high-density recording media. In the field of magnetooptical recording media, it is mainly adopted in a magnetic field modulation recording system. For a light intensity modulation (LIM) recording system, however, signal asymmetry caused by the deviation from the optimum recording conditions easily deteriorates the PRML detection procedure. In this paper, we propose an “adaptive reference level technique”, which can greatly improve the write power tolerance. It is expected to suppress the influence of the signal asymmetry in the LIM recording system.

For the light intensity modulation recording process of magnetooptical (MO) disks, we have investigated the thermal response of the recording layer for high linear density recording. By means of a computer simulation, we found that the thermal response is improved by using a 6-layer structure which has an extra thermal flow control layer composed of a thermal buffer and an extra heat sink layer, unlike the conventional 4-layer structure. The thermal response improvement was also confirmed experimentally. It is possible to optimize both the thermal response and the optical requirements separately using our 6-layer structure which will be useful when designing higher density recording MO disks.