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It is acknowledged that the inactivation of ultraviolet has been widely used in various fields. Much literature has been reported that ultraviolet C caused DNA damage to achieve inactivation of microorganisms. There is a lack of unified dose calibration and related parameters in this field. In this study, we used a device consisted of the LED of 272 nm to conduct sterilization experiments against A. baumanii. We confirmed the effectiveness of ultraviolet C sterilization for both sensitive and drug resistance strains and explored the relationship between bactericidal rate and ultraviolet doses under various irradiance. Dose requirements of various irradiance were clarified. High irradiance improved sterilization efficiency greatly. The overall damage to the total genome was observed though gel electrophoresis. Ultrastructure of damaged bacteria were investigated by transmission electron microscope in detail. The study revealed that damage to DNA and to the cytoplasm matrix and ribosomes. The study has yielded the possible effects of ultraviolet light on cells by amplifying the energy. The radiation significantly promoted the production of cell wall and cellular membrane.Significance StatementThe statistical results of bactericidal efficiency are influenced by the quantity of bacteria on the medium. Irradiance on the target surface affects the sterilization efficiency directly. And doses required in low irradiance are much more than high. A high irradiance reduced dosage efficiently to achieve the sterilization which improves the sterilization efficiency. There is a difference between low and high UVC dosage damage to the structure of bacteria. Less energy can make DNA coagulation solidified or be dispersed to the edge. Meanwhile the cytoplasm matrix is ruined. When the energy was enough, there is a boost of cell wall and cellular membrane production. The invisible light causes comprehensive damage to bacteria.

The vasoactive intestinal peptide receptor-1(VIPR1) has prominent growth effects on a number of common neoplasms. However, there were contradictions in the effect cross different cancers. We aimed to explore the effect of VIPR1 overexpression on a human lung adenocarcinoma cell line H1299. GEO dataset was used to screen differentially expressed genes in lung adenocarcinoma tissues. The expression of VIPR1 mRNA was determined in the cancer Genome Atlas (TCGA). Immunohistochemical analysis was performed to determine VIPR1 protein expression in lung adenocarcinoma and corresponding adjacent tissues (n = 22). Fluorescence real-time quantitative PCR detected the expression of VIPR1 in human normal lung epithelial cell line BEAS-2B and lung adenocarcinoma cell line H1299. Overexpression strategies were employed to assess functions of VIPR1 expression on several malignant phenotypes in H1299. The expression of VIPR1 was lower in lung adenocarcinoma tissues than that in adjacent tissues. Compared with the normal lung epithelial cells BEAS-2B, VIPR1 was down-regulated in lung cancer cells H1299 (P

Background Larger invasive thymomas are generally resected via an open approach with thoracotomy or sternotomy. Following accumulation of experience and modifications to the technique, certain invasive tumors can be safely resected by video-assisted thoracic surgery (VATS) without resorting to sternotomy. Patients and Methods Thirteen consecutive patients with large invasive thymomas, who underwent bilateral VATS thymectomy, were analyzed retrospectively. Results All patients underwent radical en bloc resection of the tumor and the involved structures, without breaching the tumor capsule or tumor seeding. In one patient, difficulties in removal of the tumors from the left brachiocephalic vein necessitated conversion to an open approach with minithoracotomy. No procedure-related hemorrhage occurred. The average operation time, including the case requiring conversion, was 132 minutes. The mean postoperative hospital stay was 4.7 days. There were no perioperative deaths. All patients completed follow up, with a mean duration of 17.4 months. Follow-up chest computed tomography showed no cases of recurrence. Conclusion With proper patient selection, preoperative planning, and a standardized approach to the operative method, we believe that bilateral VATS thymectomy can be a safe and effective procedure, and may provide an attractive alternative approach to median sternotomy.

This paper presents a semiconductor laser beam shaping system, that can collimate the irradiance profile effectively and package the laser diode(LD) at the same time. Due to the semiconductor LD is a kind of line source, a particular ellipsoidal lens is designed after both the fast-axis and the slow-axis of the laser beam analyzed. Geometrical optics analysis based on the ray tracing method is done and the formulas to calculate the shape of the lens are given. Both the theoretical and experimental result show that the laser beam system works effectively; the divergence angle is reduced to less than 0.5 degree in the fast-axial direction and 1.8 degree in the slow-axial direction. In addition, it is the same process that makes the laser beam shaper and packages the LD by using epoxy resin, which simplifies the manufacturing process and reduces the LD volume greatly. Because of the advantages of small volume, low-cost, high rigidity and easy fabrication, the shaper is of great value in the field of semiconductor LD applications.

The linewidth broadening of Distributed Feedback (DFB) semiconductor lasers under direct modulation become more and more serious with the increase of modulating data rate. So it is important to investigate externally modulated transmitter module whose dynamic linewidth is the same as its static linewidth. The integrated module including DFB-LD and LN modulator reported here has a 3 dB-bandwidth of 3.8 GHz, 4 V drive voltage, and operating wavelength at 1548 nm, its linewidth is about 100 MHz measured by Gated Delay Self Homodyne and output power is 200 (mu) W. It has been used in optical transmission system and shows good characteristics.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.