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71.
In late-phase confirmatory clinical trials in the oncology field, time-to-event (TTE) endpoints are commonly used as primary endpoints for establishing the efficacy of investigational therapies. Among these TTE endpoints, overall survival (OS) is always considered as the gold standard. However, OS data can take years to mature, and its use for measurement of efficacy can be confounded by the use of post-treatment rescue therapies or supportive care. Therefore, to accelerate the development process and better characterize the treatment effect of new investigational therapies, other TTE endpoints such as progression-free survival and event-free survival (EFS) are applied as primary efficacy endpoints in some confirmatory trials, either as a surrogate for OS or as a direct measure of clinical benefits. For evaluating novel treatments for acute myeloid leukemia, EFS has been gradually recognized as a direct measure of clinical benefits. However, the application of an EFS endpoint is still controversial mainly due to the debate surrounding definition of treatment failure (TF) events. In this article, we investigate the EFS endpoint with the most conservative definition for the timing of TF, which is Day 1 since randomization. Specifically, the corresponding non-proportional hazard pattern of the EFS endpoint is investigated with both analytical and numerical approaches.  相似文献   
72.
现如今,“90后”农民工已经成为了农民工群体中的主力军,是新生代农民工的代表。对比老一代农民工,他们身上有着鲜明的特点和对待城市生活全新的态度。当然他们面临着融入城市难的困惑、内心自卑、孤独的困惑和工作能力不足的困惑等。力求挖掘“90后”农民工身上的特点,分析其内心存在的困惑,进而提出相应的解决对策,让他们在城市里的生活更加充满希望。  相似文献   
73.
孔子以丰厚的学识修养锻炼出成熟丰富的心理调适策略:树立崇高的价值取向;构建学习型生活方式;培养高雅的生活情趣;固守正确的交友观念;保持幽默的人生态度。这些策略对当代教师具有重要的借鉴意义。  相似文献   
74.
The problem of comparing, contrasting and combining information from different sets of data is an enduring one in many practical applications of statistics. A specific problem of combining information from different sources arose in integrating information from three different sets of data generated by three different sampling campaigns at the input stage as well as at the output stage of a grey-water treatment process. For each stage, a common process trend function needs to be estimated to describe the input and output material process behaviours. Once the common input and output process models are established, it is required to estimate the efficiency of the grey-water treatment method. A synthesized tool for modelling different sets of process data is created by assembling and organizing a number of existing techniques: (i) a mixed model of fixed and random effects, extended to allow for a nonlinear fixed effect, (ii) variogram modelling, a geostatistical technique, (iii) a weighted least squares regression embedded in an iterative maximum-likelihood technique to handle linear/nonlinear fixed and random effects and (iv) a formulation of a transfer-function model for the input and output processes together with a corresponding nonlinear maximum-likelihood method for estimation of a transfer function. The synthesized tool is demonstrated, in a new case study, to contrast and combine information from connected process models and to determine the change in one quality characteristic, namely pH, of the input and output materials of a grey-water filtering process.  相似文献   
75.
The symmetric treatment of an asymmetric approach to factor analysis is shown to provide accurate communality estimates. In comparison with existing estimates including upper and lower bounds, the present approach is shown to be superior. In one example with known communalities, the present approach perfectly captures those communalities. In two empirical examples, it is shown to produce better communality estimates than any existing method.  相似文献   
76.
Youth leadership programming has become an increasingly common context to foster basic psychological needs and promote youth development. The purpose of this qualitative study was to explore strategies involved in fostering youth needs support within six leadership programs. Two leaders and 30 youth participated in semi-structured interviews to better understand the strategies used to foster needs support. Findings revealed that leaders were able to foster a sense of relatedness among youth through building trusting adult-youth relationships and nurturing an inclusive environment. Maximizing choice and negotiating youth voice helped to foster youth’s autonomy. Finally, creating a task-oriented climate and providing intentional opportunities for skill-building helped to foster youth’s competence. Findings suggest that training for leaders is critical in understanding what, and how strategies should be employed to help foster youth needs support in leadership programming. Limitations and future directions are outlined.  相似文献   
77.
Barbara Brenner, JD, was the Executive Director of Breast Cancer Action (BCA) from 1995–2010. Before that, she was a longtime activist in the anti-war movement and an attorney who, for most of her career, practiced public policy law. After she was diagnosed with breast cancer in 1993 at the age of 41, she took the helm of BCA. Under her leadership, the organization moved into a position of national advocacy—demanding research on the causes and prevention of breast cancer, including the role of industrial pollutants. Barbara started the “Think Before You Pink” campaign, encouraging people to question whether companies that display pink ribbons actually produce products that harm women's health or generate any funds to fight breast cancer. Her blog, “Healthy Barbs,” challenged readers to critique routine healthcare practices and policies. Barbara received numerous awards, including a Jefferson Award for Public Service in 2007, the Smith College Medal in 2012, and the ACLU-Northern California's Lola Hanzel Courageous Advocacy Award in 2012. Barbara had a recurrence of breast cancer in 1996. She died of complications associated with amyotrophic lateral sclerosis, ALS, on May 10, 2013.  相似文献   
78.
This article aims to contribute to a better understanding of the role of youth organisations in enhancing the employability of young people through the development of different forms of capital: human, social and psychological. Instead of asking questions about who access extra-curricular activities that may provide young people with positional advantages in the labour market and the class biases that arise in access, the article explores whether the benefits obtained from participation vary by socio-economic background. We make use of the Youth organisations and employability (YOE) database, which contains data from over 1000 young people in more than 40 European countries on the effects of involvement in youth organisations on different forms of capital: human, social and psychological. We find positive effects of involvement on all three forms of capital. The analysis suggests that the characteristics of the involvement in youth organisations are better predictors of its outcomes than are personal characteristics, and find no significant effects of socio-economic background on the reported benefits of participation in our sample. Policy implications are derived from these findings, calling for greater policy support to increase opportunities for the involvement of young people from lower socio-economic backgrounds in youth organisations and for better informing young people of the benefits of sustained involvement with youth organisations.  相似文献   
79.
Urban sociology has tended to study interactions between passersby and “street persons” with an emphasis on the ways street persons become bothersome, harassing, or dangerous. This article moves away from the focus on the ways interactions in public go awry and focuses on how individuals account for the mundane, everyday exchanges they have with strangers who seek their help. Based on interview data (N = 31) and qualitative analysis of data from an Internet survey (N = 110), this article suggests that the presence of beggars does not inherently symbolize urban decay to passersby and does not necessarily elicit anxiety, but instead provides a valuable texture of urban life. Further, the article argues that individuals, when justifying their responses to requests for help from needy persons (beggars) in urban spaces, use a variety of cultural strategies to maintain their perception of themselves as moral persons, both when they choose to help and when they refuse. Drawing from these findings, the article suggests that urban sociology and the sociology of risk would benefit from sensitizing their studies of public interactions to the diverse meanings individuals assign to them, rather than presupposing annoyance, anxiety, or fear as their predominant characteristic.  相似文献   
80.
奥巴马政府上台后,其主要致力于应对金融危机和反恐战争.对朝政策上,其在"巧实力"外交理念的指导下,寻求在外交、经济、军事、政治、法律和文化等所有政策工具中选择正确的工具或组合.针对朝核问题的敏感性和脆弱性,奥巴马政府倾向于"冷处理",继而"多管齐下",在合作外交的框架内展开更加灵活的外交活动,促使朝鲜重返六方会谈,继续以对话方式处理相关问题,不过美国也适度增强了对朝鲜的威慑力量,奥巴马政府仍对美朝关系正常化持一种谨慎态度.  相似文献   
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