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71.
72.
The present study was conducted to assess differences in the behavioral and demographic characteristics of snuff (dip) users as compared to users of chewing tobacco. High School football players (1116) were surveyed concerning their use and perceptions of smokeless tobacco. Adolescent athletes who tried smokeless tobacco were more likely to be white, to use cigarettes, alcohol, and cigars and to have family users than those who never tried. Initial use was highest before the age of fourteen years and was influenced by friends, curiosity and family. Dippers tended to initiate use because of friends, while chewers started because of family users. Users of both dip and chew started primarily because of curiosity. Users of both were more likely to consume greater amounts to alcohol and cigarettes and to smoke cigars and pipes. It appears that the longer smokeless tobacco is consumed, the more likely both dip and chew will be used. Users of smokeless tobacco for more than two years tended to consume more of the product each week, used it for more hours/day, initiated use at an earlier age, and used it more often at school and work than those using it for less than two years. Use of cigars/pipes, consumption of alcohol, and quantity of cigarette consumption increased significantly with longer duration of smokeless tobacco use. Intervention and prevention programs would be helped by understanding differences between users of various smokeless tobacco products and differences related to the duration of use. In addition, further analyses of smokeless tobacco users should study chewers, dippers, and users of both separately. 相似文献
73.
An alternative to farmer age as an indicator of life-cycle stage: The case for a farm family age index 总被引:2,自引:0,他引:2
In studies of farming, the age of the principal decision-maker (PDM) has been associated with numerous farm structural and managerial features and has been widely accepted as a good indicator of the influence of life-cycle factors on decision-making. As such, it has become an important aspect of many quantitative studies of agricultural change. However, contemporary studies of family farming demonstrate that the concept of a single PDM in family farms is becoming an anachronism as alternative enterprises, pluriactivity and the scale of family farms force more diffuse management/operating systems. This raises questions concerning whether the age of the PDM can still be taken as representative of farm structure, strategy or life-cycle stage? Using a study conducted in the Grampian Mountains region of Scotland in 2003 this note investigates the impact of using an alternative index—compiled by averaging the age of family members working on the farm. It suggests that PDM age is a relatively poor indicator of farm structural and managerial features compared to a family age index and calls for researchers to think about alternative approaches to measuring ‘age’ as an indicator. 相似文献
74.
Jan F. M. Raes 《Statistics and Computing》1992,2(2):55-62
A decade of research into the applications of artificial intelligence in statistics has finally resulted in the appearance of commercially available statistical expert systems. This paper takes a closer look at two of these systems, which are now commercially available on microcomputers, and shows what knowledge they actually contain and how they operate. It is concluded that although the technology and concepts that drive these systems could still benefit from further improvement, the real challenge lies in defining and constructing the statistical knowledge and strategy that should be incorporated and in presenting the results to the user's full advantage. 相似文献
75.
76.
Research reports the uncertain outcome of variables affecting the life of a child of an MI parent. Nurses must avoid stereotyping children before assessment; they are to be in the forefront in assessing self-care skills and deficits to guide planning individual interventions for children and MI parents. Long-term research theory-based interventions will enhance mental health in high-risk children and families. 相似文献
77.
马亮宽 《聊城大学学报(社会科学版)》2002,4(6):34-40
同盟会建立后,许多革命党人潜入北方,为实现孙中山先生的“首都革命”而积极活动,1911年10月,清王朝在永平进行大规模军事演习,史称“永平秋操”,打入新军的革命党人第二十镇统制张绍曾,第六镇统制吴禄贞,第二混成协协统蓝天蔚秘密商定,借用秋操机会发动武装革命,一举消灭清禁卫军,攻占北京。可是在秋操的前一天夜里,武昌起义爆发,清政府惊惶失措停止了秋操。派荫昌率参加秋操的部分军队南下镇压武昌起义,张绍曾拥军抗命,拒绝南下镇压起义,发动以逼迫清王朝实行立宪为旗号的兵谏,此次兵谏是有预谋,有组织,有明确目标的革命行动,在兵谏期间与京津地区的立宪派有联系,本文对兵谏过程及其与立宪派关系进行了系统论述。 相似文献
78.
根据单片机防止程序飞出的原理,创新性的提出了PC机在无人看管下,计算机如何判断当前的运行状态,以及在无法相应其他进程时,实现自动重启的方法。从单片机的看门狗实现原理,可在PC机上实现类似看门狗的功能。介绍了PC WATHDOG的软硬件实现,以及如何设计串口通讯协议,使PC WATCHDOG通过串口接收发送通讯帧和控制帧,进行交互,达到看门狗的功能。 相似文献
79.
随着中国基础建设高峰到来,工程项目管理信息系统(PMIS)必将是大型基建工程项目管理的重要手段。阐述了基于Smart Client模式PMIS的优点,并着重分析系统基本框架,提出了一般性设计原则,为PMIS开辟一条全新的研发思路。 相似文献
80.
Are children as young as 2 years old able to interact in groups of three? The study applied the family triad model first introduced by Parke, Power, and Gottman (1979 ) to the case of peer interaction. In Experiment 1 , the model was refined for use in studies of peer interaction and applied to an existing dataset of 16 triads of newly acquainted 24‐month‐olds. In Experiment 2 , the triadic coding system was further refined and applied to 12 single‐sex triads of newly acquainted 2‐year‐olds. The findings demonstrated that 2‐year‐olds are capable of triadic interaction although the predominant interaction pattern in triads is still dyadic. Contrary to past reports, triadic interaction was more likely to occur when the children were not in conflict. Both girls and boys were capable of triadic interaction. 相似文献