Long distance fiber Bragg grating strain sensor interrogation using a high speed Raman-based Fourier domain mode-locked fiber laser with recycled residual Raman pump

We propose a novel fiber Bragg grating (FBG) sensor interrogation using a Raman-based Fourier-domain mode locking (FDML) fiber laser for a high speed and long distance measurement. A residual Raman pump after the generation of the Raman-based FDML fiber laser is recycled for secondary signal amplification in a 2-m erbium-doped fiber (EDF) to further enhance the output power. The chromatic dispersion is precisely controlled to suppress the phase noise in the FDML laser cavity, resulting in the improvement of an R-number of 1.43 mm/dB. After recycling residual pump, we achieve the 40-km round trip transmission of the sensing probe signal with a high scan rate of 30.8 kHz. With 205-mW residual pump power, the bandwidth and the maximum gain are measured to be more than 50 nm, 10.3 dB at 1550 nm, respectively. The sensitivity of the proposed Raman-based FDML fiber laser to strain is also measured, which are 0.81 pm/μstrain in the spectral domain and 0.19 ns/μstrain in the time domain, respectively

Anatomic variations of the T2 nerve root (including the nerve of Kuntz) and their implications for sympathectomy

AbstractObjective: The aim of this study was to clarify the anatomic variations of the intrathoracic nerve of Kuntz, and this should help delineate the resection margins during video-assisted thoracic sympathectomy. Methods: Sixty-six thoracic sympathetic chains of 39 adult Korean cadavers were dissected on both sides of the thorax in 27 cadavers (54 sides) and on one side in 12 cadavers (12 sides). Results: The intrathoracic nerve was observed in 45 (68.2%) sides and was present bilaterally in 48.1% of cadavers. No intrathoracic nerve or ascending ramus communicans arising from the second thoracic nerve was observed in only 5 (7.6%) sides. The diameter of the intrathoracic nerve was 1.25 ± 0.55 mm on average. The arising point of the intrathoracic nerve from the second thoracic nerve was 7.3 mm on average from the sympathetic trunk. Presence of the stellate ganglion was noted in 56 (84.8%) sides, and 6 (9.1%) sides showed a single large ganglion formed by the stellate and the second thoracic sympathetic ganglia. The second thoracic sympathetic ganglion was most commonly located (50%) in the second intercostal space. Conclusion: The anatomic variations of the intrathoracic nerve of Kuntz and the second thoracic sympathetic ganglion were characterized in human cadavers. It is hoped that this study will help to improve the recurrence of symptoms caused by the intrathoracic nerve in an upper thoracic sympathectomy for hyperhidrosis.J Thorac Cardiovasc Surg 2002;123:498-50

Airborne Measurements of High Pollutant Concentration Events in the Free Troposphere over the West Coast of South Korea between 1997 and 2011

Aircrafts enable the direct measurement of chemical components in the free troposphere (FT). This study employed airborne measurements to examine the occurrences of high concentrations of SO2 and NOx in the FT over the coastal region west of the Seoul metropolitan area, South Korea. The data from a long-term (1997-2011) airborne measurement campaign were used to determine the meteorological conditions favorable for carrying these pollutants into the Seoul area. The back trajectory analyses of 21 instances of high FT pollutant concentration events showed ascending patterns from the major pollutant sources, mainly the industrial complexes in eastern China, in 9 instances and passing patterns in 12 instances. In the ascending instances, developing low-pressure systems over the source regions provide favorable conditions to uplift air pollutants from the surface into the FT. In the passing instances, an anomalous low-pressure system near the surface prevented airflows from descending into the boundary layer and upper-level anticyclonic systems helped to keep the ascending airflows in the FT. This study proposes the basic mechanisms for predicting air quality in the Seoul area, considering that air pollutants in the FT often entrain into the boundary layer to increase local concentrationsopen0

Overexpression of CFH gene in pterygiumv patients

Purpose: To investigate the expression of complement factors in pterygium tissues compared to normal conjunctival samples, using next-generation RNA sequencingMethods: Twenty pterygium and 20 healthy conjunctival samples were obtained from 19 patients who consented to pterygium excision and conjunctival autograft surgery. Tissues (pterygium and normal conjunctiva) were analyzed using next-generation RNA sequencing. Significant gene lists were obtained using DAVID, GSEA, and KEGG for enriched pathway analyses of differentially expressed genes. Realtime polymerase chain reaction was performed to validate differential expressions of complement factors.Results: There was 3.15 ± 2.6, 3.21 ± 4.6, 3.03 ± 1.83, 4.28 ± 6.12, and 4.96 ± 1.89-fold increase in the expression of CFH, C2, C1QB, C1QC, and MASP1, respectively, in pterygium samples compared to normal conjunctival samples. Pterygium size correlated well with the expression of CFH, C1QB, C1QC and MASP1.Conclusion: Alternative and lectin complement systems are activated in pterygia samples compared to normal conjunctival samples.Keywords: Pterygium; Complement factor; RNA sequencin

Tracing the historical origin of Joseon mummies considering the structural similarities between the burial systems of Korean and Chinese dynasties

Joseon mummies have proved to be excellent subjects for scientific research on the health and disease statuses of pre-modern Korean peoples. Despite its academic significance, the origins of the Hoegwakmyo tomb in which the Joseon mummy was discovered have not yet been entirely revealed. Meanwhile, over the past several decades, there have been some reports on mummies and cultural artifacts preserved very well in the tombs of several Chinese dynasties (especially Song, Yuan, Ming and Qing). Although the Chinese tombs were very diverse in structure, we note that some graves among them were structurally very similar to Joseon Hoegwakmyo tombs. Before the Hoegwakmyo tomb in Korea, there were already similar tombs in China, inside which dead persons were mummified like the Joseon mummies. Considering that the Hoegwakmyo tomb of the Joseon Dynasty was established by the influence of the Confucian ideology, the Korean and Chinese mummies might share common cultural origins in history

Second Serial Transverse Enteroplasty Procedure in an Infant with Extreme Short Bowel Syndrome

The serial transverse enteroplasty (STEP) procedure is a novel technique to lengthen and taper the bowel in patients with short bowel syndrome. The advantages of STEP include not only technical ease and simplicity, but also the ability to repeat the procedure. Herein, we report a case of extreme short bowel syndrome that was successfully treated by the second STEP procedure. A 3-day old newborn girl underwent STEP because of jejunal atresia with the small bowel length of 15 cm, but her bowel elongation was not enough to escape from short bowel syndrome. At the age of 6 months, she underwent a second STEP procedure. The bowel lengthening by the second STEP made her tolerable to enteral feeding with body weight gain and rescued her from short bowel syndrome. This case showed that second STEP is very helpful in treatment of extreme short bowel syndrome

A case of hepatoblastoma misdiagnosed as combined hepatocellular carcinoma and cholangiocarcinoma in an adult

Hepatoblastoma usually occurs in children under the age of 2 years, with very few cases reported in adults. We experienced a case of adult hepatoblastoma in a 36-year-old female with chronic hepatitis B. She had experienced sudden onset abdominal pain. Her serum alpha-fetoprotein level was markedly elevated, and abdominal CT showed a 9-cm mass with internal hemorrhage in the right hepatic lobe with hemoperitoneum, so an emergency hepatic central bisectionectomy was performed. The initial histologic examination revealed that the mass mimicked combined hepatocellular carcinoma and cholangiocarcinoma with spindle-cell metaplasia of the cholangiocarcinoma element. Follow-up abdominal CT performed 3 months later showed a 5.5-cm metastatic mass in the left subphrenic area. Laparoscopic splenectomy with mass excision was performed, and hepatoblastoma was confirmed histologically. A histologic re-examination of previously obtained surgical specimens also confirmed the presence of hepatoblastoma. Metastatic hepatoblastoma was found at multiple sites of the abdomen during follow-up, and so chemotherapy with cisplatin, 5-fluorouracil (5-FU), and vincristine was applied, followed by carboplatin and doxorubicin. Despite surgery and postoperative chemotherapy, she died 12 months after symptom onset

bending resistance and cyclic fatigue resistance of waveone gold reciproc blue and hyflex edm instruments

Abstract Background/purpose Several single-file systems manufactured using different heat treatment and operated by different kinematics have been released. This study compared the bending resistance and cyclic fatigue resistance of three NiTi files, and examined their phase-transformation behavior. Materials and methods WaveOne Gold Primary (WOG), Reciproc Blue R25 (RPB), and HyFlex EDM OneFile (HDM) were tested (N = 40/instrument). A vertical load was applied to a point 3 mm from the tip, and the stress was measured until a displacement of 3 mm. Tests were conducted at either room temperature (RT: 22 °C) or body temperature (BT: 37 °C) (n = 10). Cyclic fatigue resistance tests were performed in an artificial canal, which had a curvature angle of 40° and a 5-mm radius. Tests were conducted at either RT or BT (n = 10). Instruments were operated according to the manufacturers' instructions. Test results were analyzed using the Kruskal–Wallis and the Mann–Whitney tests. Additional three instruments of each brand were subjected to differential scanning calorimetry (DSC). Results At RT the bending resistance of three files were not significantly different. However, at BT the bending resistance of RPB was highest, followed by WOG, and HDM (P  Conclusion HDM presented superior flexibility and cyclic fatigue resistance at BT