[Experimental Methods and Result Analysis of a Variety of Spectral Reflectance Properties of the Thin Oil Film].

In order to analysis the oil spill situation based on the obtained data in airborne aerial work, it's needed to get the spectral reflectance characteristics of the oil film of different oils and thickness as support and to select the appropriate operating band. An experiment is set up to measure the reflectance spectroscopy from ultraviolet to near-infrared for the film of five target samples, which means petrol, diesel, lubricating oil, kerosene and fossil, using spectral measurement device. The result is compared with the reflectance spectra of water in the same experimental environment, which shows that the spectral reflection characteristics of the oil film are related to the thickness and the type of the oil film. In case of the same thickness, the spectral reflectance curve of different types of film is far different, and for the same type of film, the spectral reflectance curve changes accordingly with the change of film thickness, therefore in terms of the single film, different film thickness can be distinguished by reflectance curves. It also shows that in terms of the same film thickness, the reflectance of diesel, kerosene, lubricants reaches peak around 380 nm wavelength, obviously different from the reflectance of water, and that the reflectance of crude oil is far less than that of water in more than 340 nm wavelength, and the obtained reflection spectrum can be used to distinguish between different types of oil film to some extent. The experiment covers main types of spilled oil, with data comprehensively covering commonly used detect spectral bands, and quantitative description of the spectral reflectance properties of film. It provides comprehensive theoretical and data support for the selection of airborne oil spill detection working band and the detection and analysis of water-surface oil spill.

Pharyngocutaneous fistula after total laryngectomy: A systematic review and meta-analysis of risk factors.

OBJECTIVE: The pharyngocutaneous fistula (PCF) is the troublesome complication after total laryngectomy. Despite a large number of investigations having been performed, there is still controversy about which factors are most significant for PCF. The objective of the present meta-analysis was to analyze the potential risk factors for PCF after total laryngectomy. DATA SOURCES: Published English-language literature. REVIEW METHODS: PubMed, Ovid, Cochrane, and Web of Science databases were systematically searched using multiple search terms. Twenty-one studies with 3832 patients were identified. The quality of evidence was assessed by The National Institute for Health and Clinical Excellence. RESULTS: Sixteen studies involving 2598 patients were included for the meta-analysis. The results showed that, tumor subsite (RR=0.64, 95% CI 0.47-0.88, P<0.01), T stage (RR=0.70, 95% CI 0.51-0.96, P=0.03), previous radiotherapy (RR=0.62, 95% CI 0.46-0.84, P<0.01), postoperative hemoglobin <12.5g/L (RR=0.46, 95% CI 0.27-0.76, P<0.01), and surgical margin (RR=0.41, 95% CI 0.22-0.74, P<0.01) were the risk factors associated with the development of PCF. CONCLUSIONS: From the results of our study, several significant risk factors for PCF are identified. Methodologically high-quality comparative studies are needed for further evaluation.

[Histopathological study on the regularity of pyriform sinus carcinoma invading adjacent tissue and structure].

OBJECTIVE: To explore the regularity invading adjacent tissue of pyriform sinus carcinoma. METHODS: The whole organ serial section of 68 total or partial laryngectomy and hypopharyngectomy specimen of pyriform sinus carcinoma were histopathologically studied. RESULTS: In 68 pyriform sinus carcinoma, invaded ventricular and paraglottic spaces was 63 and 38 cases respectively, the difference of invasive frequency of both spaces was significantly marked (chi2 = 21.37, P < 0.01). Thyroid cartilage had the most invaded frequency of 92.6% (63/68). The all touching and pressing invasion of laryngeal cartilage was 89 times, and infiltrating invasion was 51 times. The invasive frequency of lateral cricoarytenoid muscle, posterior cricoarytenoid one, thyroarytenoid and interarytenoid ones were 63.2% (43/68), 57.4% (39/68), 55.9% (38/68), 51.5% (35/68) respectively. The invasive frequency of cricoarytenoid and cricothyroid joints were 30.9% (21/68), 17.6% (12/68) respectively. The invasive frequency of superior laryngeal nerve was 67.7% (44/65) , and more than that of recurrent laryngeal nerve (18/65, 27.7%). The pyriform sinus medial wall carcinoma was 14 cases, lateral wall carcinoma 18 cases, medial and lateral wall carcinoma 36 cases. The invaded pyriform sinus apex was 34 cases, normal its apex was 26 ones, submucous invasion of its apex was 8 ones. Light lymphocytic invasion was 66.2% (45/68) and seen most in pyriform sinus carcinoma. Submucous and leaping invasion of pyriform sinus carcinoma were 24 and 8 cases. CONCLUSIONS: Intralaryngeal invasion of pyriform sinus carcinoma arose through paraglottic space first. Laryngeal cartilage membrane and their cartilage were anatomical obstacle against cancerous invasion. Lateral cricoarytenoid muscle, posterior cricoarytenoid one, thyroarytenoid and interarytenoid ones were often invaded. Pyriform sinus medial wall carcinoma invaded intralaryngeal structure easily, its lateral wall carcinoma may invade upward, downward and outward along thyroid cartilage interior wall, medial and lateral wall carcinoma may invade intralaryngeal and extralaryngeal structure, and was the most serious lesion. The invasion of pyriform sinus apex is an important sign of pyriform sinus carcinoma spreading downward to inferior and peripheral tissues of hypopharynx.