Modified dual Mach-Zehnder interferometers with new locating algorithm for intrusion detection.

A new type of dual Mach-Zehnder interferometer (DMZI) scheme is presented to eliminate the polarization induced fading usually encountered in fiber-optic intrusion detection systems that use DMZIs. With such a new optical scheme, two identical signal waveforms with only a time delay that corresponds to the location of intrusion can always be obtained without using a polarization control loop. In the study, we also present a new algorithm for locating the intrusion-induced disturbance on the fiber. The experiments carried out in our lab have demonstrated that locating errors of <26 m can be obtained with the presented system used for detecting an intrusion point on a 250 meter long fiber cable. Also, the proposed DMZI system has been tested for years without changing any optical components except the laser type and the length of the sensing fiber. Notably, the thresholds for determining the intrusion have never been altered since the laser type was changed in 2018. In addition, detections of the clockwise and counter-clockwise signals have maintained a condition of high interference visibility, and the locating capability has remained at the same level.

Gastrointestinal complications and extraintestinal manifestations of inflammatory bowel disease in Taiwan: A population-based study.

BACKGROUND: Despite a rising incidence of inflammatory bowel disease (IBD) in Taiwan, the clinical presentation of IBDs in this population has yet to be well characterized. Therefore, the aim of our study was to identify and describe the clinical features of gastrointestinal (GI) complications and extraintestinal manifestations (EIMs) of IBDs in the Taiwanese population. METHODS: We conducted a retrospective study between 1998 and 2011, with relevant medical information extracted from the National Health Insurance Research Database. The diagnoses of IBD, GI complications, and EIMs were defined from the health registry using the appropriate International Classification of Diseases 9 codes. RESULTS: A total of 3153 patients with IBDs were identified: 611 with Crohn's disease (CD) and 2542 with ulcerative colitis, with GI complications and EIMs identified in 22.2% and 11.9% of cases, respectively. CD was associated with an increased incidence of intestinal fistula, perforation, obstruction, peritonitis and perianal disease, and ulcerative colitis with benign neoplasm of the colon. Colorectal cancer developed in 0.35% of patients. Children with CD characteristically have more complex intestinal complications. The prevalence of EIMs was higher in females and in CD, with peripheral arthritis identified as the most common EIMs, overall. The rate of major EIMs affecting the articular, cutaneous, and visual systems was lower than the rate reported in Western countries. CONCLUSION: Our study found that CD had a more complicated course, with a higher incidence of GI complications and EIMs. However, the prevalence of intestinal complications, perianal disease, and major EIMs was less common than in Western countries. This study provided a distinct clinical feature of IBD in Taiwan.

Fast foods--are they a risk factor for functional gastrointestinal disorders?

BACKGROUND AND OBJECTIVES: Fast-food consumption has greatly increased in Taiwan. Frequent fast food intake is associated with both allergy and obesity. The aim of this study was to describe fast food habit changes, and to assess the relationship between fast food intake and the risk of functional gastrointestinal disorders (FGIDs) among Taiwanese adolescents. METHODS AND STUDY DESIGN: This analysis used data from the Nutrition and Health Survey in Taiwan (NAHSIT) of high school students conducted in 2011. A total of 2,042 adolescents (12-19 years) completed the questionnaire. The survey included the Rome III criteria for FGIDs, translated into Chinese for adolescents. Respondents with previously diagnosed chronic organic gastrointestinal diseases were excluded from the study. RESULTS: In total, 2,034 children were enrolled. 545 subjects (26.8%) had history of at least one FGID. 88.1% of the subjects reported fast foods consumption. A significantly higher prevalence of FGIDs was noted in adolescents with a history of fast foods consumption, compared with those reported not to have ingested fast foods in the past 30 days (27.6% vs 20.6%, p=0.024). An increased risk of FGIDs in children and adolescents was associated with fast food intake (OR 1.8, 95% CI: 1.78-1.83). CONCLUSIONS: FGIDs were common among Taiwanese adolescents. Fast-food consumption may contribute to a positive association with the development of functional gastrointestinal disorders. Lower fiber intake and more frozen desserts in the diet may be complicit in FGIDs. The findings have public health relevance in regard to the global increase in fast food consumption.

Neutron yield and induced radioactivity: a study of 235-MeV proton and 3-GeV electron accelerators.

This study evaluated the magnitude of potential neutron yield and induced radioactivity of two new accelerators in Taiwan: a 235-MeV proton cyclotron for radiation therapy and a 3-GeV electron synchrotron serving as the injector for the Taiwan Photon Source. From a nuclear interaction point of view, neutron production from targets bombarded with high-energy particles is intrinsically related to the resulting target activation. Two multi-particle interaction and transport codes, FLUKA and MCNPX, were used in this study. To ensure prediction quality, much effort was devoted to the associated benchmark calculations. Comparisons of the accelerators' results for three target materials (copper, stainless steel and tissue) are presented. Although the proton-induced neutron yields were higher than those induced by electrons, the maximal neutron production rates of both accelerators were comparable according to their respective beam outputs during typical operation. Activation products in the targets of the two accelerators were unexpectedly similar because the primary reaction channels for proton- and electron-induced activation are (p,pn) and (γ,n), respectively. The resulting residual activities and remnant dose rates as a function of time were examined and discussed.

Ultrasound-guided perineural steroid injection to treat intractable pain due to sciatic nerve injury.

PURPOSE: Sciatic neuropathy is a rare but serious complication of cardiac surgery. Neuropathic pain following nerve injury can be severely debilitating and largely resistant to treatment. We present a case of this complication where ultrasound-guided perineural steroid injection at the site of the sciatic nerve injury provided excellent pain relief and facilitated subsequent rehabilitation. CLINICAL FEATURES: A 17-yr-old boy developed bilateral sciatic neuropathy after a nine-hour cardiac surgical procedure in the supine position, resulting in debilitating dysesthesia refractory to neuropathic pain therapies and leading to severe functional limitation. With magnetic resonance imaging of the lower extremities, the location of the lesion was determined to be from the level of the superior gemellus to the level of the quadratus femoris. An ultrasound-guided injection of triamcinolone 20 mg and lidocaine 40 mg around both sciatic nerves at the level of the lesion was administered two months after the surgery, and the pain score (rated on a scale 0-10) at rest decreased from 9-10 to 1 two weeks after the injection. CONCLUSIONS: There are a limited number of reports in the literature on sciatic nerve injuries associated with cardiac surgery. This case illustrates the efficacy of ultrasound-guided steroid injection around sciatic nerves at the level of superior gemellus in treating our patient's neuropathic pain.