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Cisplatin is a well-known chemotherapy medication used to treat numerous cancers. However, treatment with cisplatin in cancer therapy has major side effects, such as nephrotoxic acute kidney injury. Adult vertebrate kidneys are commonly used as models of cisplatin-induced nephrotoxic acute kidney injury. Embryonic zebrafish kidney is more simplified and is composed simply of two nephrons and thus is an excellent model for the investigation of cisplatin nephrotoxicity. Here, we developed a novel model to induce cisplatin nephrotoxicity in adult zebrafish and demonstrated that intraperitoneal injection of cisplatin caused a decline in kidney proximal tubular function based on fluorescein-labeled dextran uptake and alkaline phosphatase staining. We also showed that cisplatin induced histological injury of the kidney tubules, quantified by tubular injury scores on the periodic acid-Schiff-stained kidney sections. As shown in a mouse model of cisplatin-induced nephrotoxicity, the activation of poly(ADP-ribose) polymerase (PARP), an enzyme implicated in cisplatin-induced cell death, was markedly increased after cisplatin injection in adult zebrafish. Furthermore, pharmacological inhibition of PARP using a specific PARP inhibitor PJ 34 hydrochloride (PJ34) or 3-aminobenzamide ameliorated kidney proximal tubular functional and histological damages in cisplatin-injected adult zebrafish kidneys. Administration of a combination of PARP inhibitors PJ34 and 3-aminobenzamide additively protected renal function and histology in zebrafish and mouse models of cisplatin nephrotoxicity. In conclusion, these data suggest that adult zebrafish are not only suitable for drug screening and genetic manipulation but also useful as a simplified but powerful model to study the pathophysiology of cisplatin nephrotoxicity and establish new therapies for treating human kidney diseases.

Venous reflux may occur in all parts of the great saphenous vein (GSV). The GSV diameter generally increases when venous reflux occurs, and the extent of venous dilation may be altered on the basis of size and location of the reflux within the GSV. We examined which part of the GSV is the most sensitive and dilated in association with venous reflux.We retrospectively evaluated the data of 99 patients (198 limbs) with signs and symptoms of venous insufficiency of both lower limbs from January 2016 to December 2016. We performed ultrasound to examine the venous reflux and to measure the diameter of the GSV. The GSV was divided into four locations: saphenofemoral junction, midthigh, lower thigh (LT), and below the knee. The patients were divided into two groups according to the presence or absence of reflux.There were 87 limbs that had venous reflux and 111 limbs that had no reflux. The diameter of the GSV with reflux was significantly larger than that of GSVs without reflux only at the LT (4.7 mm vs 4.2 mm; P .001), and the highest area under the receiver operating characteristic curve was 0.642 at the LT. The cutoff value of the LT diameter for association with reflux was 5 mm (P = .025).The cutoff diameter of the LT was 5 mm. We recommend treatment of symptomatic reflux, and LT diameter may be useful for follow-up before and after treatment.

Objectives In this study, we investigated the anti-inflammatory effects of silymarin on cerulein-induced acute pancreatitis (AP) in mice. Methods Cerulein (50 μg/kg) was injected intraperitoneally once hourly for 6 hours to induce AP. To investigate the prophylactic effects of silymarin, dimethyl sulfoxide or silymarin (25, 50, and 100 mg/kg) was injected intraperitoneally 1 hour before cerulein injection. To investigate the therapeutic effects of silymarin, dimethyl sulfoxide or silymarin (100 mg/kg) was injected intraperitoneally 1, 3, or 5 hours after the first cerulein injection. Blood, pancreas, and lungs were harvested 6 hours after the last cerulein injection. Results Pre- and posttreatment with silymarin decreased the pancreas weight/body weight ratio and serum amylase activity. Furthermore, silymarin treatment inhibited pancreas and lung injury and neutrophil infiltration during cerulein-induced AP. In addition, silymarin inhibited increased secretion of proinflammatory cytokines such as interleukin 1β, interleukin 6, and tumor necrosis factor α. Finally, mitogen-activated protein kinases (MAPKs) and nuclear factor-κB were activated by cerulein, and only p38 in MAPK was inhibited by silymarin. Conclusions These findings suggest that silymarin attenuates the severity of AP through inhibition of p38 MAPKs and that silymarin could be a potential prophylactic and therapeutic agent for the treatment of AP.

In this paper, we propose an efficient and effective semi-automatic segmentation framework for knee cartilage in longitudinal MR images. The proposed method provides a seamless and efficient combination of initial automatic segmentation and interactive segmentation. The main idea is to generate and transfer the seeds, rather than the labels, of the manual segmentation results of the initial image, to segment sequential images. Here, segmentation seeds are defined as sample voxels that are highly likely to be either the organ of interest or background. Similar to user annotations by scribbles, seeds can be used to determine labels for remaining voxels. Compared to methods that transfer segmentation labels, the proposed method is able to reduce the amount of required user annotations, since it does not require the user to identify and correct erroneous regions in the transferred segmentation labels, while still providing a robust initial segmentation based on transferred initial seeds. We evaluate the effectiveness of the proposed framework by measuring the interaction time of the user to segment the cartilage within the images. We compare the results with previous methods and show that the proposed method reduces the required interaction time.

Asymmetric bilateral gynecomastia (ABGM) is uncommon, and reports on its characteristics are rare. In the present study, we investigated the clinical characteristics and surgical treatment of ABGM. We conducted a retrospective study of 1159 patients with gynecomastia who underwent subcutaneous mastectomy with liposuction at Damsoyu Hospital from January 2014 to February 2016. We then analyzed differences in the characteristics and operative results between two groups of patients: those with asymmetric and symmetric gynecomastia. Asymmetric gynecomastia was defined as gynecomastia meeting both of the following criteria: (1) upon physical examination, the size of the palpable mass below the nipple–areolar complex was twice as large as the smaller one, and (2) upon ultrasonography, the depth of the glandular tissue under the nipple-areolar complex was twice as large as the smaller one. Fifty-four patients were diagnosed with asymmetric gynecomastia. Among them, 51 had ABGM and three had unilateral gynecomastia. In the asymmetric group, more patients had a larger left than right breast (33 patients, 64.7%). The incidence of true-type (entirely glandular) breasts was significantly higher in the asymmetric group (84.3%) than in the symmetric group (p

A case report of pericardial agenesis identified in the course of a thoracoscopic resection of pulmonary sequestration in a 9-month-old boy.

We report a noble coherent optical frequency domain reflectometry (OFDR) system that simply enables measurement range enhancement up to full coherence length of a laser source. The proposed technique is based on bidirectional determination of Rayleigh backscattered signal along a fiber. To do this, complex OFDR signals are acquired with the help of $\pi / 2$ phase-shifting interferometry in a detection part and an additional delay fiber in a reference arm. Through a bidirectional determination process using the complex OFDR signals, mirrored signals appearing at both sides of the spatial domain were completely discriminated, so that ambiguity arising due to a positional origin can be removed. Bidirectional distributed strain and temperature sensing is successfully performed for the first time. Spectral shifts by applying strain to and heating of the test fiber were found to be independent on both sides of the reference position, indicating that twofold enhancement of the measurement range can be obtained compared to previous systems.

Recent mobile applications have required high data rate. In metropolitan areas where data traffic is higher than other areas, heterogeneous networks (HetNet) are used to meet the traffic demand (Hoadley and Maveddat in IEEE Commun Mag 19(2):4–5, 2012). The HetNet has several low power base stations or remote radio heads in a macro cell coverage and sometimes coordinates the low power transmission points forming virtual multiple-input and multiple-output system. In this paper, inter-relay interference (IRI) cancellation for two-path relay system is considered. In existing schemes, IRI cancellation is performed at a destination node but proposed method performs the cancellation at relay nodes to reduce the complexity of detection algorithm for the destination node. Simulation results also show that the method of this paper achieves better BER performance than the existing schemes.

In this paper, a new improved wireless transmission scheme is proposed for a wireless communication network. When the terminal is located in the edge of cell coverage, the transmitted signal is distorted by the interference and power reduction. In the proposed scheme, the terminal receives the signals through the multiple paths and pre-coded signal by the cooperative communication and the pre-coding scheme. Therefore, it reduces the problems of terminal in the edge of cell coverage.

Finasteride is commonly used for treatment of alopecia. Because finasteride is a cause of gynecomastia, there is concern regarding the continuation of finasteride therapy after mastectomy. No studies have been performed to determine whether finasteride should be continued after mastectomy when gynecomastia occurs in patients taking finasteride for the treatment of alopecia. The researchers studied the effects of finasteride on gynecomastia recurrence after mastectomy in men with gynecomastia taking finasteride for alopecia. The researchers retrospectively evaluated 1,673 patients with gynecomastia who underwent subcutaneous mastectomy with liposuction at Damsoyu Hospital from January 2014 to December 2016. In total, 52 of the patients were taking finasteride for alopecia before surgery and continued to use it in the same manner after mastectomy. Ultrasonography was performed 1 year after mastectomy. The patients’ median age was 26.5 (24.75–30) years. All 52 patients had bilateral gynecomastia. The median duration of finasteride therapy before and after surgery was 12 (5–25.75) and 33 (27.5–40.5) months, respectively. There were no statistically significant differences between the groups with and without the use of finasteride in relation to postoperative complications and recurrence rates. Taking finasteride seems to have little effect on recurrence in patients with alopecia who have undergone surgical treatment of gynecomastia. Surgeons may recommend continuous finasteride therapy in patients with alopecia who wish to take finasteride after mastectomy.

Acute pancreatitis (AP) is an inflammatory disease of the pancreas. Icariin (ICA), a flavonoid glycoside, has been reported to have several pharmacological effects; however, the anti‑inflammatory effects of ICA against AP require further study. Therefore, we aimed to investigate the effect of ICA on cerulein‑induced AP. In the present study, AP was induced by intraperitoneally administering a supramaximal concentration of cerulein (50 µg/kg/h) for 6 h. ICA was also administered intraperitoneally, and mice were sacrificed 6 h after the final cerulein injection. Blood samples were collected to determine serum amylase and lipase levels. The pancreas and lung were rapidly removed for histological examination, and the analysis of myeloperoxidase activity. In addition, reverse transcription‑quantitative polymerase chain reaction was conducted to analyze the expression of inflammatory cytokines in pancreatic tissues. Our results revealed that the administration of ICA prevented an increase in the pancreas weight/body weight ratio of mice and serum digestive enzyme levels. ICA treatment also inhibited cerulein‑induced histological injury and neutrophil infiltration of the pancreas and lung. In addition, ICA suppressed the production of pro‑inflammatory cytokines, including interleukin (IL)‑1β, IL‑6 and tumor necrosis factor‑α in the pancreas. Furthermore, ICA administration was observed to inhibit p38 activation during cerulein‑induced AP. Inhibition of p38 activation resulted in alleviated pancreatitis. Collectively, our results suggested that ICA exhibits anti‑inflammatory effects in cerulein‑induced AP via the inhibition of p38.

Angioleiomyoma and lipoleiomyoma are rarely found tumors in the inguinal canal. We present two cases of laparoscopic removal of angioleiomyoma and lipoleiomyoma in the female inguinal canal. In Case 1, a 35-year-old woman was admitted to our hospital with left inguinal swelling and intermittent pain. A hypoechoic well-marginated mass was observed on ultrasonography. Laparoscopic complete tumor excision and posterior wall repair were performed, and a diagnosis of angioleiomyoma was confirmed on histopathological evaluation. In Case 2, a 55-year-old woman was admitted with a painful right inguinal swelling. A hypoechoic well-marginated ovoid mass was observed on ultrasonography. Laparoscopic complete tumor excision and posterior wall repair were performed, and a diagnosis of lipoleiomyoma was confirmed on histopathological evaluation. Laparoscopic tumor excision and posterior wall repair are effective treatments of leiomyomas in the inguinal canal.

In this work, a loop sensor for Arc-Flash detections has been developed in order to trip a circuit breaker within 2.5 ms after an Arc-Flash event. For an efficient capturing of the flash light, plastic optical fibers, where light attenuations are larger than those in silica-based ones, with different diameters and surface conditions were utilized. The performance was comparatively analyzed with those ofa point sensor and a commercialized product. The point sensor module was designed for hemisphere-like capturings of Arc-Flasheslarger than 3 kA at 2 meters from the sensor. On the other hand, the loop sensor allowed 360-degree-detections around the fiber axisand the measurement range was dependent on the length of the fiber connected to the sensor module. The trip-level-dependent bright-ness measurement results showed that the fabricated point sensor and loop sensor satisfied a brightness condition, 10~40 klux, and theresponses of the system to Arc-Flashes were completed within 2.5 ms.Keywords: Arc-Flash sensor, Plastic optical fiber, Protective relay

We propose a simple fade-free fiber-optic interferometer for vibration sensing. A 90° optical hybrid based quadrature detection with subsequent π/2 phase shifting technique has shown to be fully free from the phase bias induced fading.

Guggulsterone (GS) is a phytosterol that has been used to treat inflammatory diseases such as colitis, obesity, and thrombosis. Although many previous studies have examined activities of GS, the effect of GS on lipopolysaccharide (LPS)-induced inflammatory responses in mouse inner medullary collecting duct-3 (mIMCD-3) cells have not been examined. Therefore, here, we investigated the anti-inflammatory action of GS on mIMCD-3 cells exposed to LPS. LPS treatment on mIMCD-3 cells produced pro-inflammatory molecules such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) significantly; however, GS treatment significantly inhibited the production of pro-inflammatory molecules. In addition, GS inhibited the degradation of Iκ-Bα and translocation of NF-κB on mIMCD-3 cells. These results suggest that GS could inhibit inflammatory responses in collecting duct cells which could contribute to kidney injury during systemic infection.

Lupeol is a triterpenoid commonly found in fruits and vegetables and is known to exhibit a wide range of biological activities, including antiinflammatory and anti-cancer effects. However, the effects of lupeol on acute pancreatitis specifically have not been well characterized. Here, we investigated the effects of lupeol on cerulein-induced acute pancreatitis in mice. Acute pancreatitis was induced via an intraperitoneal injection of cerulein (50 µg/kg). In the lupeol treatment group, lupeol was administered intraperitoneally (10, 25, or 50 mg/kg) 1 h before the first cerulein injection. Blood samples were taken to determine serum cytokine and amylase levels. The pancreas was rapidly removed for morphological examination and used in the myeloperoxidase assay, trypsin activity assay, and real-time reverse transcription polymerase chain reaction. In addition, we isolated pancreatic acinar cells using a collagenase method to examine the acinar cell viability. Lupeol administration significantly attenuated the severity of pancreatitis, as was shown by reduced pancreatic edema, and neutrophil infiltration. In addition, lupeol inhibited elevation of digestive enzymes and cytokine levels, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1, and interleukin (IL)-6. Furthermore, lupeol inhibited the cerulein-induced acinar cell death. In conclusion, these results suggest that lupeol exhibits protective effects on cerulein-induced acute pancreatitis. Copyright © 2015 John Wiley & Sons, Ltd.

Guggulsterone (GS), a plant steroid and a compound found at high levels in Commiphora myrrha, exhibits anti-inflammatory, anti-cancer, and cholesterol-lowering effects. However, the potential of GS to ameliorate acute pancreatitis (AP) is unknown. The aim of this study was to evaluate the effects of GS on cerulein-induced AP. AP was induced by intraperitoneally injecting supramaximal concentrations of the stable cholecystokinin analog cerulein (50 μg/kg) hourly for 6 h. In the GS-treated group, GS was administered intraperitoneally (10, 25, or 50mg/kg) 1 h before the first cerulein injection. Mice were sacrificed 6 h after the final cerulein injection. Blood samples were collected to measure serum lipase levels and evaluate cytokine production. The pancreas and lung were rapidly removed for morphologic and histological examinations, flow cytometry analysis, myeloperoxidase (MPO) assay, and real-time reverse transcription-polymerase chain reaction analysis. Pre-treatment with GS attenuated cerulein-induced histological damage, reduced pancreas weight/body weight ratio, decreased serum lipase levels, inhibited infiltrations of macrophages and neutrophils, and suppressed cytokine production. Additionally, GS treatment suppressed the activation of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) in the pancreas in cerulein-induced pancreatitis. In conclusion, our results suggest that GS attenuates AP via deactivation of ERK and JNK.

Measurement range enhancement technique is proposed for distributed sensing of optical frequency domain reflectometry (OFDR) system. By using quadrature detection method in detection part, measurement range can be two times extended compared to conventional OFDR. Distributed strain sensing capability is experimentally reported with extended range up to full coherence length of tunable laser source by analyzing Rayleigh back-scattering signal obtained from the proposed quadrature detection of OFDR system.

A novel scheme of plastic optical fiber (POF) based arc flash sensor capable of tracing arc event locations is presented. Incident position of flash light can simply be known by measuring the ratio of intensities at both fiber-ends, since the intensity of the flash light assisted by side-coupling of the fiber is generally attenuated a the fiber length. The arc flash sensor which can cover a wide range up to 10 m with a high spatial resolution of ±10 cm is experimentally demonstrated using the POF. Arc flash intensity can also be known by analyzing the coupled light intensity level at both fiber ends.

Objective : Portulaca oleracea (PO) has been used as an important traditional medicine for inflammatory and bacterial diseases in East Asia. However, the protective effects of PO on acute pancreatitis (AP) is not well-known. Therefore, this study was performed to identify the anti-inflammatory and prophylactic effects of PO on cerulein-induced AP. Methods : AP was induced in mice via intraperitoneal injection of supramaximal concentrations of the stable cholecystokinin analogue cerulein (50 ㎍/㎏) given every hour for 6 times. Water extracts of PO (100, 300, or 500 ㎎/㎏) was administrated intra-peritoneally 1 h prior to the first injection of cerulein. The mice were killed at 6 h after the final cerulein injection. Pancreas and lung we re rapidly removed for morphologic and histochemical examination, myeloperoxidase (MPO) assay. Blood samples were taken to determine serum amylase and lipase activities. Results : Administration of PO significantly inhibited pancreatic weight /body weight ratio, pancreas and lung histological injury. And MPO activity which indicates neutrophi l infiltration was inhibited by PO extracts on cerulein-induced pancreatitis. In addition, PO administration i nhibited digestive enzymes such as serum amylase and lipase activity on cerulein-induced pancreatitis. Conclusion : Our results could suggest that pre-treatment of PO reduces the severity of cerulein-induced AP, thereby, PO could be used as a protective agent against AP. Also, this study could give a clinical basis that PO could be a drug or agent to prevent AP.

In this paper, we propose and demonstrate a Fabry-Perot interferometer (FPI) optical fiber tip sensor fabricated by a blade-sawing technique using a fiber optic patch cord for high-resolution temperature measurement. The sensor head consists of a short air FP cavity near the tip of a single-mode fiber patch cord tip. The temperature which we can measure is determined through a phase variation of the interference fringes in the reflective spectrum of the sensor. The fiber optic FPI sensor in this work can monitor the environmental temperature very accurately from 40 to 120 o C. As a result, the temperature sensitivity is obtained as 38.2 pm/ o C.

A compact, highly efficient, and passively assembled parallel optical-electrical convertor module (POECM) for active optical cable application is proposed. This paper presents our POECM structure, optical design simulation results, fabrication process, and data transmission test results, in sequence. The POECM has a compact size of $$18.5\hbox {mm} \times 10\hbox {mm} \times 2.8\hbox {mm}$$ . We confirm a data rate of total throughput at 21.6 Gbps ( $$5.4\hbox {Gbps} \times 4$$ channels) with a bit error rate of less than $$10^{-12}$$ .

In this paper, the characteristics of a humidity sensor implemented by Mach Zehnder Interferometer (MZI) in a Planar Lightwave Circuit (PLC) have been designed and demonstrated. The humidity outside is detected with polyvinylpyrrolidone (PVP) coated on the etched arm of the MZI. The length of the etched arm is 10 mm and the PVP was coated by dip-coating into the etched region. As the refractive index of the PVP changes with the surrounding humidity, the PVP-coated humidity sensor presented changes in the interferogram depending on RH (Relative Humidity) around the PLC. The measured results show that the proposed humidity sensor works successfully in the range of 30% to 80% of RH.

Two types of polymer-based optical splitters with 200 m large core are presented for optical multimode networks, such as smart home networks, intelligent automotive networks, etc. Optical splitters that have 1:1 symmetric and 9:1 asymmetric structure were fabricated by a ultra violet(UV)-imprint technology using a deep etched Si(silicon) master by the Bosch process. In this paper, we successfully fabricated the symmetric and asymmetric optical splitters with suitable optical network applications.Keywords: UV-imprint process, Optical splitter, Polymer, Optical networksOCIS codes: (060.4510 ) Optical communications; (230.1360 ) Beam splitters; (250.5460 ) Polymer waveguides

We demonstrate a novel multiwavelength light source around the 1.7-μm region based on continuous-wave (CW) supercontinuum (SC) generation for the deeper imaging of low-water-absorption sample with a spectrally sampled optical coherence tomography (OCT) system. This self-regulated Gaussian spectrum of CW SC source has an extremely smooth flat width with more than 210-nm full-width at half-maximum bandwidth centered at the 1.7-μm region, a high output power of 500 mW, and a low temporal instability with less than 0.1 dB for an hour. In order to improve the OCT signal sensitivity without increasing the optical illumination power, a multiwavelength light source based on this CW SC was implemented by using a tunable fiber Sagnac comb filter. When it was applied to the spectrally sampled OCT imaging, the multiwavelength light source enabled a dynamic range improvement, compared to conventional continuous spectral light source with the same average optical power.

Fiber optic interferometers to sense various physical parameters including temperature, strain, pressure, and refractive index have been widely investigated. They can be categorized into four types: Fabry-Perot, Mach-Zehnder, Michelson, and Sagnac. In this paper, each type of interferometric sensor is reviewed in terms of operating principles, fabrication methods, and application fields. Some specific examples of recently reported interferometeric sensor technologies are presented in detail to show their large potential in practical applications. Some of the simple to fabricate but exceedingly effective Fabry-Perot interferometers, implemented in both extrinsic and intrinsic structures, are discussed. Also, a wide variety of Mach-Zehnder and Michelson interferometric sensors based on photonic crystal fibers are introduced along with their remarkable sensing performances. Finally, the simultaneous multi-parameter sensing capability of a pair of long period fiber grating (LPG) is presented in two types of structures; one is the Mach-Zehnder interferometer formed in a double cladding fiber and the other is the highly sensitive Sagnac interferometer cascaded with an LPG pair.

An alternative interface structure design of a large-area optical waveguide for a large-area optical printed circuit board using a step-out fabrication technique is proposed. To investigate the misalignment tolerances and coupling excess losses, we simulated and compared our proposed structure to a typical straight core structure. As a result, the proposed structure was found to significantly improve the misalignment tolerance by more than 2 times and successfully conduct a data-link based on large area optical waveguide of 50 cm × 50 cm.

This paper describes solar light collecting system which employs parabolic reflector and Fresnel lens and its industrial application. We have introduced second-stage optical system so that it makes optical fiber overcome its numerical aperture limitation and also it makes focused light become collimated, which results in decreased light energy density. As result of these, light collecting efficiency become maximized and the system does not require separate cooling apparatus any more. The developed solar lighting system together with artificial light source like LED has been applied to plant factory as a hybrid lighting source. This makes us save electric energy for artificial lighting during day time. The intensity of LED light in the hybrid lighting system is controlled automatically according to ambient-light-sensor installed in the system so that the light intensity for a plant always keeps the same level no matter how the sun light changes. For a plant factory whose size is 330 square meters, when solar lighting system is applied, 28,080KWh electric energy can be saved per month.2 times.

We demonstrate a simple but sensitive hydrogen gas sensor composed of a palladium-coated long-period fiber grating (LPG). By writing an LPG in a low core index fiber, high-order cladding modes are excited. As the palladium thin layer absorbs hydrogen, the effective refractive indexes of the cladding modes are affected, thus the resonant wavelengths of the LPG are changed with a high sensitivity. With 70-nm-thick coating, 7.5 nm of the hydrogen-induced spectral shift was achieved. The spectral response of the proposed sensor to hydrogen gas and its recovery with nitrogen gas are presented.

We demonstrated the performance of a fiber sensor based on a photonic crystal fiber (PCF) for the detection of high temperatures. The proposed fiber sensor was implemented by collapsing the air holes of the PCF with an arc discharge and forming an in-fiber Mach-Zehnder interferometer. The intentionally collapsed parts in the PCF cause coupling between the core mode and the cladding modes, which produces interference fringes in the transmission spectrum. The spectral response was observed while changing the ambient temperature. The fiber sensor operated properly at high temperatures up to 1000 C. The proposed fiber sensor presented good reliability after repeated temperature variation cycles and showed low hysteresis over wide temperature range. We expect this compact fiber sensor to be applied to monitoring the high-temperature distribution around a thin film sensor and to be an alternative for a strain/pressure thin film sensor under high temperatures in harsh conditions.

We report development of a new fiber doped with PbSe quantum dots for nonlinear optical applications. PbSe quantum dots related absorption peaks were obtained at 1021, 1093 and 1351 nm. The resonant optical nonlinearity and attenuation at 1500 nm were measured to be 9.4 × 10−16 m2/W and 0.01 dB/m, respectively. The emission around 1540 nm was observed upon near resonant pumping at 1064 nm.

Warm dense conditions in titanium foils irradiated with intense femtosecond laser pulses are diagnosed using an x-ray imaging spectroscopy technique. The line shapes of radially resolved titanium Kα spectra are measured with a toroidally bent GaAs crystal and an x-ray charge-coupled device. Measured spectra are compared with the K-shell emissions modeled using an atomic kinetics - spectroscopy simulation code. Kα line shapes are strongly affected by warm (5-40 eV) bulk electron temperatures and imply multiple temperature distributions in the targets. The spatial distribution of temperature is dependent on the target thickness, and a thin target shows an advantage to generate uniform warm dense conditions in a large area.

We propose a simple hydrogen detection scheme based on a Mach-Zehnder interferometer formed with a pair of palladium-coated long-period fiber gratings (LPGs). Since an LPG pair offered a fine-structured interference fringe in its transmission spectrum, the resolution as a sensor could be appreciably enhanced compared to that of a single LPG. As the palladium layer absorbed hydrogen, the effective refractive indices of the cladding modes were increased so that the interference spectrum was blue-shifted up to 2.3 nm with a wavelength sensitivity of -0.29 nm/min for 4% of hydrogen concentration.

Recently, a need for dual transmission band interference lter has existed in the area of optical communications. We designed a ve-cavity dual-band-pass lter, which transmits the 1310 nm band and the 1550 nm band simultaneously. This design has 81 layers of Ta2O5 and SiO2 layers alternately and an overall thickness of 33.3 microns, in which most of the layers are quarter and half wavelength layers or multiples of these units, except for the last 9 layers. Based on this design, we deposited dual-band-pass lters using a dual-ion-beam sputtering method with an optical monitoring system. The results show that the lter shape has a sharp slope and that the transmittances of the 1310 nm band and the 1550 nm band are both higher than 0.5 dB.

We present a ber-type phase retarder that is implemented by using a short segment of a single-mode ber. To induce the phase retardation, we utilize the photo-induced birefringence. Though the photo-induced birefringence was small, it was enough to realize quarter-wave retardation. In our works, by cascading two ber-type quarter-wave segments in series and rotating one and/or both of them, we could con rm the potential as a polarization-state converter. All birefringence segments were encapsulated in metal tubes and were terminated with ber ferrules so that we could simultaneously rotate the birefringence axis and increase the connectivity to other devices. The theoretical results are given and are compared with the experimental ones.

In spite of controversial issues, pancreatectomy following neoadjuvant chemoradiation therapy (NeoCRT) has been applied in treating advanced pancreatic cancer. Cases of pathological complete remission (pCR) following NeoCRT is rare, and its long-term follow-up data are still lacking. From January 2000 to December 2012, medical records of the patients who underwent pancreatectomy for pancreatic ductal adenocarcinoma were retrospectively reviewed. Characteristics of the patients with pCR were summarized and their long-term follow-up data were analyzed. Among 86 patients with pancreatic cancer who underwent radical pancreatectomy following NeoCRT, 10 patients (11.6%) were reported to pCR. Nine out of 10 patients received gemcitabine-based chemoradiation therapy. Median pre-NeoCRT serum CA 19-9 was 313.5 U/ml, and post-NeoCRT serum CA 19-9 was 9.9 U/ml, which was shown to be significant difference between 2 serum CA 19-9 level (P = 0.005). Pylorus-preserving pancreaticoduodenectomy was done in 8 patients, and the others received distal pancreatosplenectomy. Postoperative chemotherapy was received in 6 patients. Disease-free survival was statistically superior in patients with pCR than patients without pCR (P 0.05). pCR is rarely reported following NeoCRT, but this condition is not telling the cure of the disease. Early recurrence in the pattern of liver metastasis and peritoneal seeding can be expected. However, long-term survival could be maintained in patients without recurrence. Further investigation is necessary for predicting failure of treatment.

Though an interleaver with Gires-Tournois (GT) etalon is very attractive for achieving smaller channel spacing and compact con- figurations, its insertion loss should be reduced further so as to utilize it in an ultra narrow DWDM system. In this article, an asymmetric input- output ports configuration is proposed to obtain efficient coupling within the interleaver and consequently to reduce the insertion loss of the in- terleaver. The interleaver fabricated with asymmetric configuration has

We demonstrate a simple and effective wavelength-tunable add/drop filter suitable for coarse wavelength division multiplexing (CWDM) systems. The filter consists of two fibers in contact side by side, with identical long-period fiber gratings (LPG) in each fiber. The LPG couples the power in the fundamental core mode to one of the cladding modes, which is then coupled to the same order cladding mode in the other fiber through evanescent-field coupling between two fibers. Finally, the cladding mode in the second fiber is coupled to its core mode with the help of the other LPG. With an optimal longitudinal offset distance of 10 em, coupling efficiency as high as -1.68 dB and side lobes smaller than -24 dB were experimentally obtained. The experimental results agreed well with the theoretical ones. The operating wavelength of the proposed add/drop filter was tunable by varying the temperature. The temperature sensitivity was measured to be -0.43 nm/ $^{\circ}C$ .

For the design of reliable micro-optical devices with a high coupling efficiency, a source-modeling method necessary for ray tracing is newly proposed. This method is based on the ray-division of an incident wavefront estimated by Gaussian beam optics. The simulation result obtained using the proposed method was compared with those of the conventional methods, and its accuracy was confirmed by the experimental results. Finally, the method was used to design a micro-optical device with two GRIN lenses and a thin-film filter.

We have implemented a distributed sensor system based on an array of fiber Bragg gratings (FBGs), which can measure up to 1000 points with a single piece of fiber. The system consists of FBGs having the same resonant wavelengths and small reflectivities (∼0.1 dB), and a wave-length tunable optical time-domain reflectometer (OTDR). To interrogate the distributed grating sensors and to address the event locations simultaneously, we have utilized the tunable OTDR. A thermoelectric temperature controller was used to tune the emission wavelength of the OTDR. The operating temperature of the laser diode was changed. By tuning the pulse wavelength of the OTDR, we could identify the FBGs whose resonant wavelengths were under change within the operating wavelength range of the DFB LD. A novel sensor cable with dry core structure and tensile cable was fabricated to realize significant construction savings at an industrial field and in-door and out-door applications. For experiments, a sensor cable having 52 gratings with 10m separations was fabricated. To prevent confusion with unexpected signals from the front-panel connector zone of the OTDR, a 1 km buffer cable was installed in front of the OTDR. The proposed system could distinguish and locate the gratings that were under temperature variation from 20°C to 70°C.

Optical fiber connectors that had a long working distance and wide alignment tolerance were implemented by utilizing long-period fiber gratings (LPGs) written in double-cladding fiber. The power coupling between two separated pieces of fiber was accomplished through the inner cladding modes of both fibers. Assisted by the LPGs, approximately 450 /spl mu/m was achieved for a 1-dB working distance, as well as about 3 mm of 3-dB working distance. When the separation between two fiber tips was 1.5 mm, the 3-dB lateral tolerance was measured to be about 30 /spl mu/m, which was five times better than was the case when not utilizing the LPGs. By using the inner cladding mode of a dispersion-compensating fiber, it was possible to implement a fiber connector that was insensitive to the perturbations at the cladding surface of the fiber. The total insertion loss of the device at the maximum coupling was 2.06 dB, from which the loss purely induced by inserting the fiber gratings was analyzed to be smaller than 0.9 dB. The experimental results show strong feasibility for implementing a simple and cost-effective fiber connector that does not require any bulk optic elements.

Plastic and creep deformations of solder joints during thermal cycling are the main factors of misalignments and power losses in optical telecommunication components. Furthermore, the increased mismatch between solder Joint-bonded areas may cause severe failure in the components. Darveaux`s creep model was implemented into a finite element program (ABAQUS) to simulate creep response of solder. Based on the finite element results, thermal fatigue reliability was predicted by using various fatigue life prediction models. Also, the effects of ramp conditions, dwelling time, and solder joint-embedding materials on the reliability were investigated under the thermal cycling conditions of the Telcordia schedule (-40∼75).

We report the formation of inner cladding modes in the optical fiber having an inner cladding structure. The inner cladding layer located between the core- and the cladding- layers of a conventional fiber might have, so called, inner cladding mode(s). The brief history of the inner cladding fiber and the spectral properties of the inner cladding mode are presented. By utilizing fiber gratings, the spectral properties of the inner cladding mode formed in Dispersion Compensating Fiber (DCF) are discussed. It was observed that one resonant peak of a long-period fiber grating was not sensitive to the variation on the cladding surface. With a fiber Bragg grating, a small group of unusual resonant Peaks was observed between the main Bragg Peak and the series of usual Peaks resulted from the mode coupling to counter-propagating cladding modes. Within the DCF by using fiber gratings, it is noted, at least one mode can be coupled to the inner cladding mode and a few outer cladding modes are severely affected by the inner cladding of the fiber.