目的新兴视频服务的功能参数设置将会直接影响到用户的认知状态,进一步影响用户体验质量,称为功能性用户体验质量(functional quality of experience,fQoE)。脑电信号蕴含丰富的大脑活动信息,能够揭示复杂脑活动中的脑网络模式,为fQoE...目的新兴视频服务的功能参数设置将会直接影响到用户的认知状态,进一步影响用户体验质量,称为功能性用户体验质量(functional quality of experience,fQoE)。脑电信号蕴含丰富的大脑活动信息,能够揭示复杂脑活动中的脑网络模式,为fQoE提供可靠的评估依据。为此,本文首次提出了一个基于脑电的脑网络构建方法以评估fQoE,并研究fQoE背后的神经机制。方法首先,通过改变功能参数诱发不同水平的fQoE,并同步收集脑电数据;然后,从脑电数据中提取单电极和多电极特征并以图结构进行融合,用以全面表征用户使用视频服务时的大脑状态;最后,使用基于自注意力图池化的脑网络构建模型来识别对fQoE敏感的脑网络,为fQoE提供可解释性,并进行分类以完成fQoE评估。结果本文以弹幕视频服务的弹幕覆盖率这一功能参数为例验证了方法的科学性和可行性。实验表明,提出的评估方法在多种视频类型的fQoE评估中均达到了满意的效果,最佳识别准确率分别为86%(鬼畜类)、81%(科技类)、80%(舞蹈类)、82%(影视类)和84%(音乐类)。结论来自fQoE相关的脑网络分析结果表明,额极、额中回、顶叶和颞叶的脑连接数量减少预示着观看弹幕视频的fQoE更高,即观看体验更好,同时也证明了功能参数通过影响人的脑状态进一步导致了fQoE的改变。本文的评估方法为fQoE的精确评估和视频服务功能参数的优化提供了来自神经生理学的定量工具和理论依据。展开更多
Eighty four throat swabs were obtained from Basrah General Hospital inpatients （N = 34）： 17 were suffering from renal failure and the other 17 were diabetics; and from outpatients （N = 50）. Throat swabs were cult...Eighty four throat swabs were obtained from Basrah General Hospital inpatients （N = 34）： 17 were suffering from renal failure and the other 17 were diabetics; and from outpatients （N = 50）. Throat swabs were cultured first in the selective media Ashdown＇s broth then subcultured on Ashdown＇s agar to isolate Burkholderia pseudomallei which was recovered from seven cases （8.33%）. Four isolates were from renal failure patients （23.53%）, two from diabetic patients （11.76%） and the seventh isolate was from an outpatient with tonsillitis. All isolates were able to produce capsules, form filament chains, exhibit swarming motility and were arabinose non assimilators （Ara-） indicative of their virulence. Additionally, isolated B. pseudomallei were found to produce protease, lipase, hemolysin, and lecithinase and were able to produce biofilm, the root of many troublesome persistent infections that resist antibiotic treatment. Susceptibility of the seven isolates of B. pseudomallei toward 11 antibiotics was assessed, isolates were found multiply resistant to all antibiotics apart from ciproflaxin. This study confirms for the first time isolation of B. pseudomallei from immunocompromised patients in Basrah city of Iraq and describes their virulence potentials.展开更多
文摘目的新兴视频服务的功能参数设置将会直接影响到用户的认知状态,进一步影响用户体验质量,称为功能性用户体验质量(functional quality of experience,fQoE)。脑电信号蕴含丰富的大脑活动信息,能够揭示复杂脑活动中的脑网络模式,为fQoE提供可靠的评估依据。为此,本文首次提出了一个基于脑电的脑网络构建方法以评估fQoE,并研究fQoE背后的神经机制。方法首先,通过改变功能参数诱发不同水平的fQoE,并同步收集脑电数据;然后,从脑电数据中提取单电极和多电极特征并以图结构进行融合,用以全面表征用户使用视频服务时的大脑状态;最后,使用基于自注意力图池化的脑网络构建模型来识别对fQoE敏感的脑网络,为fQoE提供可解释性,并进行分类以完成fQoE评估。结果本文以弹幕视频服务的弹幕覆盖率这一功能参数为例验证了方法的科学性和可行性。实验表明,提出的评估方法在多种视频类型的fQoE评估中均达到了满意的效果,最佳识别准确率分别为86%(鬼畜类)、81%(科技类)、80%(舞蹈类)、82%(影视类)和84%(音乐类)。结论来自fQoE相关的脑网络分析结果表明,额极、额中回、顶叶和颞叶的脑连接数量减少预示着观看弹幕视频的fQoE更高,即观看体验更好,同时也证明了功能参数通过影响人的脑状态进一步导致了fQoE的改变。本文的评估方法为fQoE的精确评估和视频服务功能参数的优化提供了来自神经生理学的定量工具和理论依据。
文摘Eighty four throat swabs were obtained from Basrah General Hospital inpatients （N = 34）： 17 were suffering from renal failure and the other 17 were diabetics; and from outpatients （N = 50）. Throat swabs were cultured first in the selective media Ashdown＇s broth then subcultured on Ashdown＇s agar to isolate Burkholderia pseudomallei which was recovered from seven cases （8.33%）. Four isolates were from renal failure patients （23.53%）, two from diabetic patients （11.76%） and the seventh isolate was from an outpatient with tonsillitis. All isolates were able to produce capsules, form filament chains, exhibit swarming motility and were arabinose non assimilators （Ara-） indicative of their virulence. Additionally, isolated B. pseudomallei were found to produce protease, lipase, hemolysin, and lecithinase and were able to produce biofilm, the root of many troublesome persistent infections that resist antibiotic treatment. Susceptibility of the seven isolates of B. pseudomallei toward 11 antibiotics was assessed, isolates were found multiply resistant to all antibiotics apart from ciproflaxin. This study confirms for the first time isolation of B. pseudomallei from immunocompromised patients in Basrah city of Iraq and describes their virulence potentials.
