船舶防碰撞导航预警系统设计

该文介绍了一个基于GPS技术、无线网络技术、嵌入式系统等技术的船舶防碰撞导航预警系统(SCNAS)。该系统的应用可实现船舶的航行预警机制,加强长江航道信息化管理。该系统现已成功完成船舶测试,即将投入生产。

结合SCAN方法与离散小波变换的无损彩色图像加密算法

基于提高图像在移动互联网传输的安全性,结合SCAN与二维离散小波设计一种无损的彩色图像加密方案。彩色明文图像被划分为红、绿、蓝三分量,并对其分块处理;由两个混沌系统生成随机序列,作为SCAN方法得扫描路径扰乱或扩散;利用二维离散小波变换将图像从空域转化到频域进而产生子带矩阵,根据上述产生的随机序列对子带矩阵进行置乱;利用二维逆离散小波变换将图像转化到空域,得到密文图像。实验结果表明,该算法的像素相关性较低,且密钥空间大,是一种无损的彩色图像加密算法。

Somatic copy number alterations are predictive of progression-free survival in patients with lung adenocarcinoma undergoing radiotherapy

Objective:Lung cancer is the most common cause of cancer-related deaths worldwide.Somatic copy number alterations(SCNAs)have been used to predict responses to therapies in many cancers,including lung cancer.However,little is known about whether they are predictive of radiotherapy outcomes.We aimed to understand the prognostic value and biological functions of SCNAs.Methods:We analyzed the correlation between SCNAs and clinical outcomes in The Cancer Genome Atlas data for 486 patients with non-small cell lung cancer who received radiotherapy.Gene set enrichment analyses were performed to investigate the potential mechanisms underlying the roles of SCNAs in the radiotherapy response.Our results were validated in 20 patients with lung adenocarcinoma(LUAD)receiving radiotherapy.Results:SCNAs were a better predictor of progression-free survival(PFS)in LUAD(P=0.024)than in lung squamous carcinoma(P=0.18)in patients treated with radiotherapy.Univariate and multivariate regression analyses revealed the superiority of SCNAs in predicting PFS in patients with LUAD.Patients with stage I cancer and low SCNA levels had longer PFS than those with high SCNA levels(P=0.022).Our prognostic nomogram also showed that combining SCNAs and tumor/node/metastasis provided a better model for predicting long-term PFS.Additionally,high SCNA may activate the cell cycle pathway and induce tumorigenesis.Conclusions:SCNAs may be used to predict PFS in patients with early-stage LUAD with radiotherapy,in combination with TNM,with the aim of predicting long-term PFS.Therefore,SCNAs are a novel predictive biomarker for radiotherapy in patients with LUAD.

雪旺细胞源营养神经活性物质对大鼠视网膜节细胞损伤的作用

目的 观察雪旺细胞 (Schwann cells,SC)源营养神经活性物质 (SC derived neurotrophic ac-tivity,SCNA)对 Sprague- Dawly(SD)大鼠视神经损伤后视网膜节细胞 (retinal ganglion cells,RGC)存活的影响。 方法 体外培养日龄 3～ 5 d SD乳鼠 SC,收集无血清条件培养液 ,经超滤浓缩后制成冻干粉。SD大鼠分为正常对照组 ,视神经夹伤对照组 ,视神经夹伤溶剂对照组 ,视神经夹伤 SCNA治疗组 ,每组 2 0只眼。荧光金逆行标记 RGC后 7d,除正常对照组外均行球后视神经夹伤 ,SCNA治疗组将 10 0 ng SCNA注入大鼠玻璃体腔内。分别于视神经夹伤后第 5、7、14、2 1、2 8d将动物灌注固定 ,做全视网膜铺片 ,行 RGC计数。 结果 视神经夹伤后第 7d RGC开始减少 ,14d时降至正常对照的 70 .2 % ,2 8d时降至 40 .5 %。 SCNA治疗组 7d时 RGC数开始减少 ,但 14、2 1、2 8d RGC数均明显多于视神经夹伤对照组及视神经夹伤溶剂对照组 (P<0 .0 1)。 结论 在视神经夹伤后眼内注射 SCNA能减少 RGC的死亡对 RGC损伤有保护作用。