Ursolic acid inhibits proliferation and induces apoptosis of HT-29 colon cancer cells by inhibiting the EGFR/MAPK pathway

rectal cancer.     

Linking ethnic/racial discrimination to adolescent mental health: Sleep disturbances as an explanatory pathway

Ethnic/racial discrimination is associated with negative psychosocial outcomes, and this study considered sleep disturbance as a mediating pathway. Employing a combination of daily diary and biannual surveys, multilevel structural equation models estimated the indirect effects of sleep/wake concerns on negative, anxious, and positive mood, rumination, and somatic symptoms. In a sample of 350 urban Asian (74% Chinese, 8% Korean, 4% Indian, 1% Filipinx, 1% Vietnamese, and 12% other), Black, and Latinx (25% Dominican, 24% South American, 22% Mexican, 15% Puerto Rican, 5% Central American, and 9% other) youth (M = 14.27 years, 69% female, 77% U.S. born, 76% monoethnic/racial, data collected from 2015 to 2018), there was evidence for sleep disturbances mediating the impact of ethnic/racial discrimination on adjustment. Nighttime disturbance, daytime dysfunction, and daytime sleepiness evidenced partial or full mediation for daily- and person-level outcomes (υ = 0.1%–17.9%). Reciprocal associations between sleep disturbances and negative mood and rumination were also observed.     

电视原理教学中图像信号形成原理的深入分析

电视原理是高校电子专业学生一门重要的专业选修课,工程实践性很强,跟随新技术、新成果的节奏较快,因此,围绕该课程的教学内容的深入探讨一直在进行中。本文通过对图像形成原理的进一步分析,使学生能够完全、深刻了解和掌握这部分知识。同时在文章最后还介绍了相关的新成果内容。     

Research progress of the role and mechanism of extracellular signal-regulated protein kinase 5 (ERK5) pathway in pathological pain

Extracellular signal-regulated protein kinase 5 (ERK5), also known as big mitogen-activated protein kinase 1 (MAPK1), is an important member of ERK family, which is a subfamily of the large MAPK family. ERK5 is expressed in many tissues, including the dorsal root ganglion (DRG) neurons and the spinal cord. In this review, we focus on elaborating ERK5-associated pathway in pathological pain, in which the ERK5/CREB (cyclic adenosine monophosphate (cAMP)-response element-binding protein) pathway plays a crucial role in the transduction of pain signal and contributes to pain hypersensitivity. ERK5 activation in the spinal dorsal horn occurs mainly in microglia. The activation of ERK5 can be mediated by N-methyl-d-aspartate (NMDA) receptors. We also elaborate the relationship between ERK5 activation and nerve growth factor-tyrosine kinase A (NGF-TrkA), and the connection between ERK5 activation and brain-derived neurotrophic factor (BDNF) in pathological pain in detail.     

Evaluating the impact of an environmental education programme: an empirical study in Mexico

This study draws on information from 11 in‐depth interviews, two focus groups and 72 written questionnaires to evaluate an extra‐curricular environmental education programme on forestry designed for preparatory school students from a small rural community in Mexico. Specifically, the study assessed the impact of the programme on the ecological knowledge of 72 students. Qualitative feedback suggests that students learnt about forestry, acquired greater awareness of the importance of conservation for the local environment and enjoyed the participatory teaching methods used in the programme. Quantitative results show a positive and significant association between the number of times a student participated in the programme and the student’s ecological knowledge. Students who participated in the programme once had a 16.3% higher knowledge on ecological concepts and knew, on average, 1.5 more local forest plants than students who never attended it (p<.001). Findings suggest that the inclusion of participatory environmental education programmes in preparatory schools would improve the acquisition of ecological knowledge. Further research could consider the consistency of the findings by replicating participatory methods presented here and by using an experimental research design.     

Matching/mismatching revisited: an empirical study of learning and teaching styles

This paper presents results of a research project that explored the relationship between matching and mismatching instructional presentation style (breadth-first and depth-first) with students' cognitive style (field-dependence/-independence) in a computer-based learning environment. 73 postgraduate students were asked to create Web pages using HTML, using instructional materials that were either matched or mismatched with their cognitive styles. Significant differences in performance on a multiple choice test of conceptual knowledge were found for students learning in matched and mismatched conditions. Performance in matched conditions was significantly superior to that in mismatched conditions. However, significant effects were found for gender, matching mainly affecting male students. Performance on a practical test of Web page creation was not linked to matching or mismatching, but was linked to an interaction between gender and instructional presentation style. The findings provide support for the notion that matching and mismatching can have significant effects on learning outcomes. The paper concludes with suggestions for further research.     

Proportional reasoning in the laboratory: an intervention study in vocational education

Based on insights into the nature of vocational mathematical knowledge, we designed a computer tool with which students in laboratory schools at senior secondary vocational school level could develop a better proficiency in the proportional reasoning involved in dilution. We did so because we had identified computations of concentrations of chemical substances after dilution as a problematic area in the vocational education of laboratory technicians. Pre- and post-test results indeed show that 47 students aged 16–23 significantly improved their proportional reasoning in this domain with brief instruction time (50–90 min). Effect sizes were mostly large. The approach of using a visual tool that foregrounds mathematical aspects of laboratory work thus illustrates how vocational mathematical knowledge can be developed effectively and efficiently.     

Cover article:Sensors for the mTORC1 pathway regulated by amino acids

This review mainly focuses on the sensors for the mechanistic target of rapamycin complex 1(mTORC1) pathway regulated by specific amino acids—arginine, leucine, and methionine.Regulation of the mTORC1 pathway Sensors for arginine-mediated mTORC1 Sensors for leucine-mediated mTORC1 Sensors for methionine-mediated mTORC1     

Shades of gray: an autoethnographic study of race in the academy

The study is an autoethnographic case study of one Black man’s experiences, both within and outside academe. Two strands of vignettes – one personal, the other professional – run throughout the paper. The two strands are presented in a format similar to parallel editing used in film editing. The overarching goal of the piece is to offer a view of the author’s experiences involving race in higher education. The study uses reflexive writing as a method of revisiting and interrogating the author’s experience and illustrating how this process of reflexivity impacts on his own in notions of race. The result of these writings ranges from reinforcing relatively simplistic views of race to disrupting his preconceived ideas. While some themes that arise from this piece may resemble previous works on race, racial identity and racial politics, there are unique perspectives and interpretations presented in this paper that are attributable in no small measure to the fact that the author is a Black man who was raised by a white family in white America. Since the author did not have the cultural experience of being Black until he went to college, a white cultural lens largely informs his understandings of his own experiences. However, the act of writing uncovers inconsistencies within the author’s own interpretations and theories of race. In fact, it appears that the author has competing theories of race that present dilemmas for his thinking and dealings with race in higher education. The study concludes that writing can be used as an effective method for reflecting, interrogating and modifying one’s own perspective to arrive at more nuanced and complex understandings, which reinforce the conclusion that race plays out in messy and complicated ways.     

Writing instruction in first grade: an observational study

As schools work to meet the ambitious Common Core State Standards in writing in the US, instructional approaches are likely to be examined (National Governors Association Center for Best Practices, Council of Chief State School Officers, 2010). However, there is little research on the current state of instruction. This study was designed to provide a comprehensive analysis of first-grade writing instruction across 13 schools in one state in the US. Daylong observations were conducted four times during the year in 50 first-grade classrooms. Using a time-sampled, observational protocol, observers coded multiple dimensions of instruction, including grouping, instructional focus, teacher instructional activity, and student writing activity. Results revealed that writing was taught for less than 30 min a day on average, and instruction in skills or process writing was common. Most instruction was organized in whole-class settings with teachers either presenting information or asking students questions. Variability in the amount and focus of writing instruction and in student writing activity was examined at the classroom and school levels. A small number of classrooms and schools were identified with distinctive patterns in their approach to instruction and writing activity. Several moderate relationships were found between the writing instructional focus and the nature of student writing. These findings suggest that first-grade writing instruction is inconsistent across classrooms and schools and point to instructional implications for teachers and schools in the US.     

Creativity in advertising design education: an experimental study

Have you ever thought about why qualities whose definitions are elusive, such as those of a sunset or a half-opened rose, affect us so powerfully? According to de Saussure (Course in general linguistics, 1983), the making of meanings is closely related to the production and interpretation of signs. All types of design, including advertising design, are about meaning-making. This study examines the effectiveness of a problem-based learning (PBL) approach in enhancing student designers’ creative flexibility in advertising design. A semiotic approach is employed to examine hand-sketched print advertisements for a bakery promoting the metaphorical theme Bread is Life produced by participants in a series of PBL workshops (the experimental group) and a series of lecture-based workshops (the control group). The visual representations realised through these sketches in association with the metaphor were categorised into different signifiers by five experienced creative directors and are compared on an inter-group basis. The results of the semiotic analysis show the experimental group to have generated a wider variety of signifiers than the control group, thus reflecting the higher degree of creative flexibility that results from the use of a PBL approach. Theoretically, this empirical study addresses a number of conceptual issues in advertising design, creativity, problem solving, divergent thinking and semiotics. Practically, it contributes to an understanding of how a PBL approach can contribute to the enhancement of semiotic association skills amongst student designers in a professional communication context.     

Plus/minus grading and motivation: an empirical study of student choice and performance

This paper considers whether student motivation might be impacted by the replacement of a straight (A, B, C, D, F) grading system with a plus/minus system (A, A?, B+ … D?, F). The data that are examined are from several undergraduate economics classes at a mid‐sized midwestern university in the United States. The data includes student characteristics, student performance and students’ choices of either a plus/minus or a straight grading system. In this admittedly small‐scale study students, who chose plus/minus grading, were not significantly more motivated than students who opted for straight grading.     

Promoting historical contextualisation in classrooms: an observational study

The aim of this observational study is to explore how history teachers promote historical contextualisation in their lessons. Historical contextualisation is the ability to situate phenomena and individuals’ actions in the context of time, historical location, long-term developments, or specific events to give meaning to these phenomena and actions. Using the Framework for Analysing the Teaching of Historical Contextualisation (FAT-HC), five trained raters observed eight history teachers twice. To further analyse the observation scores, the FAT-HC items were divided into eight categories while distinguishing between items that demonstrate historical contextualisation and items focusing on engaging students in historical contextualisation processes. The results indicate that the teachers in the sample did not explicitly promote historical contextualisation in their lessons. No teacher obtained a mean FAT-HC score >2.00 on a four-point scale. The teachers mainly demonstrated historical contextualisation, while engaging students in historical contextualisation processes was observed far less often. The findings can be used to help teachers formulate domain-specific instruction to promote students’ ability to perform historical contextualisation.