Growth of Mediastinal Bronchial Artery Aneurysms in a Patient With Bronchiectasis.

Mediastinal bronchial artery aneurysm (BAA) is a rare and life-threatening disease. We experienced the first case confirming that, despite only slight deterioration of bronchiectasis, mediastinal BAAs expanded remarkably. A 61-year-old female was hospitalized because of hemoptysis. Her respiratory condition required intubated mechanical ventilation. Bronchial artery angiography unexpectedly found unruptured mediastinal BAAs. These BAAs were enlarged compared with those seen in a computed tomography (CT) taken 5 years before. We successfully embolized both BAAs and peripheral arteries. Mediastinal BAAs are capable of increasing more rapidly than a slightly deteriorated underlying bronchiectasis. For rapid and accurate diagnosis of BAA, bronchial artery angiography is important.

Second harmonic generation at 399 nm resonant on the 1S0-1P1 transition of ytterbium using a periodically poled LiNbO3 waveguide.

We demonstrate a compact and robust method for generating a 399-nm light resonant on the 1S0 - 1P1 transition in ytterbium using a single-pass periodically poled LiNbO3 waveguide for second harmonic generation (SHG). The obtained output power at 399 nm was 25 mW when a 798-nm fundamental power of 380 mW was coupled to the waveguide. We observed no degradation of the SHG power for 13 hours with a low power of 6 mW. The obtained SHG light has been used as a seed light for injection locking, which provides sufficient power for laser cooling ytterbium.

Rapid spectrum measurement at 3 µm over 100 nm wavelength range using mid-infrared difference frequency generation source.

We demonstrate a broadband rapid scanning light source in the 3-µm region by using difference frequency generation (DFG). The DFG source consists of a module with quasi-phase-matched LiNbO3 ridge waveguides, a 1-µm-band wide swept range laser for the pump source, and a 1.5-µm continuous wave laser for the signal source. The sweep rate and the tuning bandwidth of this source are 20 kHz and 100 nm, respectively. This source enables us to evaluate the temperature dependence of absorbance of methane gas.

Dual wavelength 3.2-µm source for isotope ratio measurements of (13)CH(4)/(12)CH(4).

Difference frequency generation using one 1.58-µm and two 1.06-µm distributed feedback Bragg-grating laser diodes and a ridge-type PPLN alternately provide two 3.2-µm coaxial waves resonant with individual isotopic transitions separated by 13 cm(-1). The ν(3) band R(6) A(2) allowed transition of (13)CH(4) and the ν(3) band R(6) A(2) weakly allowed transition of (12)CH(4) are an ideal pair for isotope ratio measurements. The (13)CH(4)/(12)CH(4) isotope ratio is determined for three sample gases with a relative uncertainty of 0.7 ‰, and it is confirmed that the temperature dependence is smaller than the uncertainty.

Submucosal tumors: comprehensive guide for the diagnosis and therapy of gastrointestinal submucosal tumors.

Small submucosal tumors (SMT) without symptoms are frequently found by endoscopic and radiological examinations. To find proper diagnostic measures and therapeutic indications for histologically undiagnosed SMT, we reviewed published articles in PubMed between 1990 and March 2013 using the key words 'submucosal tumor' and the name of a specific disease. SMT is observed in a wide range of gastrointestinal (GI) diseases and conditions, including compression by extra-GI organs and lesions, congenital tumors, inflammation, and benign as well as malignant neoplastic lesions. In the diagnosis of diseases and decision-making for therapy, endoscopic ultrasonography (EUS) and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) may play a key role. Symptomatic SMT and SMT histologically diagnosed as malignant or potentially malignant tumors such as gastrointestinal stromal tumor (GIST) should be treated by surgery. SMT >5 cm, SMT increasing in size and those with'high-risk features' including irregular border, heterogeneous internal echo such as anechoic area, and heterogeneous enhancement by contrast media may also be removed by surgery. Laparoscopic approach is feasible for gastric GIST <5 cm and this is considered less invasive than the open approach. Emerging techniques using flexible endoscopes appear less invasive, but require further evidence and are still under clinical study. Correct diagnosis of SMT is challenging; however, EUS and EUS-FNA are useful in the histological diagnosis and clinical decision-making. In the future, minimally invasive approaches may be a mainstream of surgical treatment for small SMT.

Generation of time-bin entangled photon pairs by cascaded second-order nonlinearity in a single periodically poled LiNbO(3) waveguide.

Entangled photon pairs are one of the most important resources for the development of quantum communication technologies. In order to produce pulsed photon pairs in the telecommunication band from 1.5 mum pump light, most of the previous experiments used two successive periodically poled lithium niobate (PPLN) waveguides. We report what we believe to be a new method using cascaded second-order nonlinearity in a single PPLN waveguide to produce high-purity time-bin entangled photon pairs. We confirmed the generation of entanglement through a two-photon interference experiment showing a coincidence fringe with a visibility of up to 97%.

Efficient 494 mW sum-frequency generation of sodium resonance radiation at 589 nm by using a periodically poled Zn:LiNbO3 ridge waveguide.

A solid-state-laser based single-frequency 589 nm light source that can be easily used in the laboratory is needed for sodium spectroscopy studies and cold sodium atom experiments. This paper shows that by using a periodically poled Zn-doped LiNbO(3) ridge waveguide for sum-frequency generation, we can obtain a high conversion efficiency to 589 nm light from two sub-watt 1064 and 1319 nm Nd:YAG lasers via a simple single pass wavelength conversion process without employing an enhancement cavity. A 494 mW light at 589 nm is generated and achieves overall conversion efficiency from the laser power of 41%. Excellent long-term stability of output power is obtained and its standard deviation is characterized to be 0.09%.

Polarization-independent, differential-phase-shift, quantum-key distribution system using upconversion detectors.

We propose and demonstrate a polarization-independent, differential-phase-shift, quantum-key distribution system with upconversion detectors. Even though the detectors have polarization dependency, use of alternative polarization modulation and a two-bit delay interferometer achieves polarization-insensitive operation. In an experiment, sifted key bits were polarization-independently generated over 50 km fiber.

[Renal transection conservatively treated three times by selectively transarterial embolization (TAE): a case report].

A 12-year-old-man presented with left flank pain after a traffic accident on October 14, 2006. Computed tomography (CT) revealed major left renal hematoma and transection (IIIb). Selectively transarterial embolization (TAE) was performed to control upper transected renal bleeding on the same day, and again to do rebleeding two days later. Because CT revealed left perirenal urinoma caused by upper transected kidney on October 18, TAE was performed for the upper transected kidney not to function. Five months after left renal injury, CT demonstrated the left kidney successfully preserved without hydronephrosis, urinoma and hematoma. The patient was well and could be conservatively treated without hypertension and other complications. In previous reports, only a part of renal injury (III) cases with conservative treatment converted to nephrectomy, whereas approximately half of them with surgical treatment resulted in nephrectomy. Therefore, it is important to treat them as conservatively as possible and to preserve renal function, even in cases of major renal blunt injury.

Unequally spaced multiple mid-infrared wavelength generation using an engineered quasi-phase-matching device.

We propose a novel quasi-phase-matched (QPM) device that can generate unequally spaced multiple wavelengths. Unequally spaced multiple QPM peaks can be obtained by employing the optimized phase modulation of a periodic domain structure. We fabricated a LiNbO3 waveguide device for 3.2-3.4 microm band difference frequency generation based on the design. Using the multiple mid-infrared outputs, we demonstrate the detection of multiple hydrocarbon gases, namely, methane, ethylene, and ethane.

High-power, tunable difference frequency generation source for absorption spectroscopy based on a ridge waveguide periodically poled lithium niobate crystal.

A novel waveguide for difference frequency generation in the mid-IR spectral region at 3.52 mum is characterized. High mid-IR power of 15 mW and an external conversion efficiency of up to 19 %W( -1) have been obtained. An optical beam propagation factor M(2) =1.18 was determined using the second moment method. A simple 2-f absorption spectra demonstrates the potential of this mid-IR source for high precision trace gas sensing applications.

Simultaneous observation of CO isotopomer absorption by broadband difference-frequency generation using a direct-bonded quasi-phase-matched LiNbO3 waveguide.

Rovibration absorption lines both of 12CO and 13CO are observed simultaneously with the output of a 2 microm broadband difference frequency generated in a direct-bonded quasi-phase-matched LiNbO3 waveguide, which is a 50 mm device with a single quasi-phase-matching period that is operated at a constant temperature. The wavelength conversion efficiency and the difference-frequency generation bandwidth reach 100%/W and 100 nm, respectively. The idler output bandwidth in the 2 microm region is obtained by group-velocity matching or phase-mismatch minimization when a 0.94 microm pump laser diode and a 1.55 microm tunable signal source are used.

Generation of pulsed polarization-entangled photon pairs in a 1.55-microm band with a periodically poled lithium niobate waveguide and an orthogonal polarization delay circuit.

We report a scheme for generating pulsed polarization-entangled photon pairs based on conversion from time-bin entanglement to polarization entanglement by use of an orthogonal polarization delay circuit and post-selection. We have experimentally demonstrated the scheme, using a periodically poled lithium niobate waveguide, and successfully obtained polarization entanglement in the 1.55-microm telecom wavelength band.

Multiple quasi-phase-matched LiNbO3 wavelength converter with a continuously phase-modulated domain structure.

We have devised a novel device structure for a multiple quasi-phase-matched wavelength converter. Optimized continuous phase modulation of a periodic domain structure makes possible multichannel pumping with minimum loss of efficiency. Using the device, we demonstrate variable and simultaneous wavelength conversion of wavelength-division multiplexed signals.