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221.
AIM:To predict treatment success using only simple clinical data from peg-interferon plus ribavirin therapy for chronic hepatitis C. METHODS:We analyzed the clinical data of 176 patients with chronic hepatitis and hepatitis C virus genotype 1 who received 48 wk standard therapy, derived a predictive formula to assess a sustained virological response of the individual patient using a logistic regression model and confirmed the validity of this formula.The formula was constructed using data from the first 100...  相似文献   
222.
Subadult age estimation should rely on sampling and statistical protocols capturing development variability for more accurate age estimates. In this perspective, measurements were taken on the fifth lumbar vertebrae and/or clavicles of 534 French males and females aged 0–19 years and the ilia of 244 males and females aged 0–12 years. These variables were fitted in nonparametric multivariate adaptive regression splines (MARS) models with 95% prediction intervals (PIs) of age. The models were tested on two independent samples from Marseille and the Luis Lopes reference collection from Lisbon. Models using ilium width and module, maximum clavicle length, and lateral vertebral body heights were more than 92% accurate. Precision was lower for postpubertal individuals. Integrating punctual nonlinearities of the relationship between age and the variables and dynamic prediction intervals incorporated the normal increase in interindividual growth variability (heteroscedasticity of variance) with age for more biologically accurate predictions.  相似文献   
223.
In an effort to standardize data collection and analysis in age estimation, a series of computational methods utilizing high‐dimensional image data of the age indicator have recently been proposed as an alternative to subjective visual, trait‐to‐phase matching techniques. To systematically quantify the reproducibility of such methods, we investigate the intrascan variability and within‐ and between‐observer reliability in initial scan data capturing and editing using 3D laser scans of the Suchey–Brooks pubic symphysis casts and five shape‐based computational methods. Our results show that (i) five observers with various training background and experience levels edited the scans consistently for all three trials and the derived shape measures and age estimates were in excellent agreement among observers, and (ii) the computational methods are robust to a measured degree of scan trimming error. This study supports the application of computational methods to 3D laser scanned images for reliable age‐at‐death estimation, with reduced subjectivity.  相似文献   
224.
The aim of this study was to evaluate the applicability of Cameriere’s European formula for age estimation in children in South China and to adapt the formula to establish a more suitable formula for these children. Moreover, the performance of dental age estimation based on Cameriere’s method combining the developmental information of permanent teeth (PT) and third molar (TM) was also analysed. Orthopantomographs of 720 healthy children in Group A, and orthopantomographs of 320 children and 280 subadults in Group B were assessed. The samples of Group A were divided into training dataset 1 and test dataset 1, and the samples of Group B were also divided into training dataset 2 and test dataset 2. A South China-specific formula was established based on the training dataset 1, and the comparison of accuracy between the Cameriere’s European formula and the South China-specific formula was conducted with the test dataset 1. Additionally, a PT regression model, a TM regression model, and a combined regression model (PT + TM) were established based on the training dataset 2, and the performance of these three models were validated on the test dataset 2. The Cameriere’s European formula underestimated chronological age with a mean difference (ME) of −0.47 ± 1.11 years in males and −0.69 ± 1.19 years in females. However, the South China-specific formula underestimated chronological age, with a mean difference (ME) of −0.02 ± 0.71 years in males and −0.14 ± 0.73 years in females. Compared with PT model and TM model, the PT and TM combined model obtained the smallest root mean square error (RMSE) of 1.29 years in males and 0.93 years in females. In conclusion, the South China-specific formula was more suitable for assessing the dental age of children in South China, and the PT and TM combined model can improve the accuracy of dental age estimation in children.

Key points

  • Orthopantomographs of 720 healthy children in Group A, and orthopantomographs of 320 children and 280 subadults in Group B were assessed.
  • A South China-specific formula was established based on the training dataset 1, and the comparison of accuracy between the Cameriere’s European formula and the South China-specific formula was conducted with the test dataset 1.
  • A PT regression model, a TM regression model, and a combined regression model (PT + TM) were established based on the training dataset 2, and the performance of these three models were validated on the test dataset 2.
  • The South China-specific formula was more suitable for assessing the dental age of children in South China, and the PT and TM combined model can improve the accuracy of dental age estimation in children.
  相似文献   
225.
本文基于辽宁省21所高校的1912份调查数据,运用Logistic回归和结构方程模型验证了个体因素、家庭因素和社会因素对高校毕业生自主创业意愿的影响。研究结果发现:个体因素中,个体的传记特征(性别、是否独生子女、户口所在地、是否本省生源、就读高校类型、所学专业)、创业环境认知和创业心态对高校毕业生的创业意愿有显著影响;家庭因素中,父亲职业、母亲受教育程度和家庭收入的影响显著;社会因素中,社会舆论导向和就业压力对高校毕业生自主创业意愿有正向影响,而高校创业引导与创业政策宣传的影响不显著。因而,建议从提高创业素质与能力、发展创业教育、改善创业环境、完善创业扶持政策、加强创业舆论宣传等方面提升高校毕业生的自主创业热情和创业成功率。  相似文献   
226.
This study used hierarchical linear modeling to compare longitudinal patterns of adolescent religious service attendance and club attendance, and to contrast the longitudinal relations between adolescent adjustment and religious service versus club attendance. Participants included 1050 students (47% girls) encompassing a school district in Canada, who completed the survey first in grade nine and again in grades 11 and 12. Results demonstrated that patterns of religious service attendance over time were quite different from other clubs. Religious attendance was uniquely associated with several indicators of positive as well as negative adjustment. Club involvement, conversely, was only associated with positive adjustment––particularly for individuals who reported sustained involvement over time. Findings suggest that religious services may provide some unique experiences––both positive and negative––over and above what may be provided in other clubs, and that sustained, rather than sporadic participation in clubs, may be especially important for adolescent adjustment.
Jan FritjersEmail:

Marie Good   is a Ph.D. candidate in Developmental Psychology at Brock University. Her research interests include adolescent religion and spirituality, adolescent identity development, and youth risk-taking. Teena Willoughby   is a Professor in the Departments of Child and Youth Studies and Psychology. Her research interests include adolescent resilience, particularly with regard to academic underachievement, risk behaviours, optimal experiences, and media/technology influences on lifestyle choices. Jan Fritjers   is an Assistant Professor in the Departments of Child and Youth Studies and Psychology. His research interests include the role of motivational, volitional, and relationship factors in children’s learning.  相似文献   
227.
Increasingly, researchers have found relationships between a strong, positive sense of racial identity and academic achievement among African American youth. Less attention, however, has been given to the roles and functions of racial identity among youth experiencing different social and economic contexts. Using hierarchical linear modeling, the authors examined the relationship of racial identity to academic outcomes, taking into account neighborhood-level factors. The sample consisted of 564 African American eighth-graders (56% male). The authors found that neighborhood characteristics and racial identity related positively to academic outcomes, but that some relationships were different across neighborhood types. For instance, in neighborhoods low in economic opportunity, high pride was associated with a higher GPA, but in more advantaged neighborhoods, high pride was associated with a lower GPA. The authors discuss the need to take youth’s contexts into account in order to understand how racial identity is active in the lives of African American youth.
Tabbye M. Chavous (Corresponding author)Email:

Christy M. Byrd   is a Ph.D. student in the Combined Program in Education and Psychology at the University of Michigan. Her research interests include how school and neighborhood contexts shape racial identity and personal development for children and adolescents. Tabbye M. Chavous   is an Associate Professor in the School of Education and the Department of Psychology at the University of Michigan. Her primary academic affiliation is with the Combined Program in Education and Psychology. She received her Ph.D. in Community Psychology from the University of Virgina. Her research interests center around social, developmental, and contextual influences on the academic and psychological development of African American adolescents, with an emphasis on gender and racial identity development, school climate effects, and family socialization processes.  相似文献   
228.
229.
This article unearths the salient factors that trap the aspiring middle class in their progression towards a stable middle class in the City of Johannesburg, South Africa. The study utilises a quantitative case study design, drawing on a sample of 449 aspirants and 578 middle-class heads of households from the 2021 Gauteng City-Region Observatory Quality of Life Survey. A binary logistic regression model was used to analyse these salient factors (key determinants) and their impact on the social mobility of the aspirant middle class. Findings reveal a significant relationship between social mobility and education, racial inequality, asset ownership, access to economic opportunities and proximity to amenities. We suggest local government policies that positively influence the conditions of these determinants for sustained mobility of the aspirant middle class over time.  相似文献   
230.
The ISO/IEC 17020 and 17025 standards both include requirements for impartiality and the freedom from bias. Meeting these requirements for implicit cognitive bias is not a simple matter. In this article, we address these international standards, specifically focusing on evaluating and mitigating the risk to impartiality, and quality assurance checks, so as to meet accreditation program requirements. We cover their meaning to management as well as to practitioners, addressing how these issues of impartiality and bias relate to forensic work, and how one can effectively evaluate and mitigate those risks. We then elaborate on specific quality assurance policies and checks and identify when corrective action may be appropriate. These measures will not only serve to meet ISO/IEC 17020 and 17025 requirements, but also enhance forensic work and decision-making.  相似文献   
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