Diffusing information

His many publications include Theories of Mass Communication; Understanding Mass Communication; Milestones in Mass Communication Research;and, with Otto N. Larsen, The Flow of Information.     

Plasma,oral fluid and sweat wipe ecstasy concentrations in controlled and real life conditions

In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition.     

循环经济的尺度问题探讨

循环经济是一种新型的生态经济发展模式,而尺度作为生态学中的核心问题,已经引起了广泛关注。把尺度理论和循环经济理论研究与实践有机地结合起来,在分析循环经济尺度内涵的基础上,可以对循环经济的空间尺度和时间尺度进行拓展性的阐释,并由此可以得到四点基本结论。     

党的先进性建设的十大历史经验

认真总结党的先进性建设的历史经验,对于建立健全保持共产党员先进性的长效机制、推进新时期党的建设新的伟大工程,具有十分重要的现实意义和深远的历史意义。本文从十个方面总结了党的先进性建设的历史经验。     

骨缺损修复材料的研究现状

由肿瘤切除和创伤造成的骨缺损是日常医疗活动中常见的现象。目前,骨缺损修复的研究方向主要在骨缺损的材料上,从修复质量、免疫排斥和疾病传播等多方面来衡量,自体骨都是最佳的选择,成为骨移植的金标准。但由于供骨量有限,取骨又造成第二术区的创伤,因而它的临床应用受到了很大的限制。同种异体骨的来源比自体骨多,但与宿主间的免疫排斥反应和疾病传播是其缺点。异种骨的来源广泛,免疫原性性强、处理过程复杂和骨诱导性小是其不足之处。人工合成骨成型迅速,在计算机辅助设计和辅助制作的帮助下,能更好的合成与缺损骨形态接近的骨移植替代材料,人工合成骨的骨诱导性和仿生物性骨结构方面还不能令人满意。近年来复合骨移植和组织工程骨研究的快速发展给骨缺损修复带来了新的希望。用异体骨、异种骨或人工合成骨、金属钛网等作为支架,以富含原始骨细胞和骨生成因子的自体骨髓为填充材料修复骨缺损已取得相对满意的临床效果。组织工程骨则利用自体的原始骨细胞作为种子细胞在体外经过适当扩增,复合组织相容性好的支架材料和相关生长因子,植入体内后通过细胞分化和参与骨改建,最后形成新骨以修复骨缺损,但组织工程骨也面临着如何在骨内形成血管和神经如何支配的问题。总之,骨缺损修复材料研究的大方向为:最小的自体创伤;最大程度的仿自体骨,并不断接近自体骨的形态、结构和功能,朝着这个目标,人类的不懈努力,必将解决自身健康需要的复杂问题-修复骨缺损。     

我国法治社会形成中的主要因素分析

我国法治社会形成过程中,有多种因素在起作用。社会现状,这是探讨法治社会形成、发展的客观依据,也是客观条件;法文化传统,这是法治社会具有民族特色的历史资源,它是一种客观存在,但由于人们对它的认识和态度的不同,便表现为不同的主观因素;市场经济,这是法治社会基础性的推动力量,但在市场经济成熟过程中出现的一些问题,又加重了建构法治社会的任务;精神文明建设,这是造就法治社会合格主体的有效途径,它重在建设,要常抓不懈才能见效;法治国家。它与法治社会相互促进、相辅相成,二者虽有区别,但其建构过程不能截然分开。     

谈新世纪兵团的可持续发展

可持续发展是我国的一项基本国策,兵团坚持可持继发展战略具有更大的现实意义和历史意义,因为在物质资源、生态环境方面,兵团承受的压力更大.正确认识兵团所面临的压力,是兵团实施可持续发展战略的基本前提.     

思想政治工作的挑战及对策

改革的深入 ,使我国国内出现了大量新情况、新问题 ;开放的扩大 ,又使我国面临着诸多新的国际形势、新挑战。对此 ,思想政治工作越来越不适应这种新的局面 ,迫切需要我们去探索新时期思想政治工作的新规律、新方法 ,以促进我国的社会主义现代化建设。