A simple mechanical model for simulating cross-country skiing,skating technique

The role of simulation models in sport disciplines has become relevant lately due to the multiple advantages that they may offer sports teams, coaches and practitioners. This paper develops and presents a simple three-dimensional multibody dynamic model of a cross-country skier, modeling a single propulsion phase to obtain the kinetic parameters involved in the movement. A professional Olympic-level skier performed the skating technique without poles in a ski tunnel under controlled conditions and on an incline plane. Then, with a force acquisition system attached to the ski bindings and a motion capture system set on site, the leg resultant forces and the movement of specific points of the skier’s lower body were acquired. The data obtained from the motion capture system were used as the prescribed kinematic input data in the multibody model and the measured force was used later as a parameter of comparison with the results of the simple model. After simulating the technique, the calculated resultant forces seem to be in agreement with those measured in the field.     

The use of Wechsler Scales in the assessment of Native Americans of the Columbia River Basin

Native American secondary students from the Columbia Basin were found to have significant Verbal-Performance discrepancies on the WISC-R and WAIS. Mean Verbal scores were significantly below the normative mean, while Performance scores were at, or above, the normative means. These findings substantiated research with other Native American groups. Also, the Verbal and Performance scales correlated so low as to preclude the Full Scale from being an accurate representation of the “g” factor of intelligence. Further, the predictive validity of the WISC-R and the WAIS for reading and math achievement was found to be at variance with the standardization group.     

美国的食品卫生与食品安全一体化

提供全世界最安全的食品,是美国社会一直引以为傲的。尽管中餐馆在全世界普遍存在食品卫生与安全的问题,而在美国已得到较稳定的控制,这与美国政府以及全社会高度重视食品卫生与安全问题密切相关。其关于食品的立法与监督体系已日臻完善,呈现出注重细节、标准量化、公开透明、监督有力、执行果断、全民参与等特点,文中谈到的相关细节与事例,值得中国政府、食品行业以及全社会的反思与借鉴。     

Short-term professional learning that focuses on beliefs and practice: Improvements in preschool teachers’ ongoing literacy practice

An intervention study was conducted with preschool teachers to address their beliefs and practice in the area of language and literacy. A total of 27 preschool teachers, each from different early childcare centers, participated in three 1-day professional learning sessions over the course of 9 months. Learning sessions focused on three different language and literacy topics. Study participants completed a pre- and post-session questionnaire and were observed in the classroom before and after each session. Significant differences were observed in both their beliefs and practice after the intervention. Specifically, preschool teachers’ beliefs were related to their practice in two areas: oral language and vocabulary; and book reading. Based on the data, a focus on beliefs and practice in future short-term PL or workshop models may support successful outcomes in teaching practice.     

Does God Make It Real? Children’s Belief in Religious Stories From the Judeo‐Christian Tradition

Four- to 6-year-old children (N = 131) heard religious or nonreligious stories and were questioned about their belief in the reality of the story characters and events. Children had low to moderate levels of belief in the characters and events. Children in the religious story condition had higher levels of belief in the reality of the characters and events than did children in the nonreligious condition; this relation strengthened with age. Children who used God as an explanation for the events showed higher levels of belief in the factuality of those events. Story familiarity and family religiosity also affected children's responses. The authors conclude that God's involvement in a story influences children's belief in the reality of the characters and events in that story.