Assessment of cortical bone microdamage following insertion of microimplants using optical coherence tomography: a preliminary study

Objectives

The study was done to evaluate the efficacy of optical coherence tomography (OCT), to detect and analyze the microdamage occurring around the microimplant immediately following its placement, and to compare the findings with micro-computed tomography (μCT) images of the samples to validate the result of the present study.

Methods

Microimplants were inserted into bovine bone samples. Images of the samples were obtained using OCT and μCT. Visual comparisons of the images were made to evaluate whether anatomical details and microdamage induced by microimplant insertion were accurately revealed by OCT.

Results

The surface of the cortical bone with its anatomical variations is visualized on the OCT images. Microdamage occurring on the surface of the cortical bone around the microimplant can be appreciated in OCT images. The resulting OCT images were compared with the μCT images. A high correlation regarding the visualization of individual microcracks was observed. The depth penetration of OCT is limited when compared to μCT.

Conclusions

OCT in the present study was able to generate high-resolution images of the microdamage occurring around the microimplant. Image quality at the surface of the cortical bone is above par when compared with μCT imaging, because of the inherent high contrast and high-resolution quality of OCT systems. Improvements in the imaging depth and development of intraoral sensors are vital for developing a real-time imaging system and integrating the system into orthodontic practice.

     

One Policy,Disparate Reactions: Institutional Responses in Florida’s Developmental Education Reform

This paper seeks to better understand how community colleges in Florida planned to implement a new sweeping state policy pertaining to developmental education. Via a cluster analysis, we identify three distinct patterns in the ways in which the colleges responded to the policy: reformers, responders, and resisters. Further, we find that these patterns are related to the extent to which individual colleges had previously enacted campus-based developmental education reform measures, the magnitude of students previously enrolled in developmental education, and the colleges’ perceptions of the effectiveness of the policy.     

Differentiating Different Types of Cognitive Load: a Comparison of Different Measures

Recent studies about learning and instruction use cognitive load measurement to pay attention to the human cognitive resources and to the consumption of these resources during the learning process. In order to validate different measures of cognitive load for different cognitive load factors, the present study compares three different methods of objective cognitive load measurement and one subjective method. An experimental three-group design (N = 78) was used, with exposure to seductive details (extraneous cognitive load factor), mental animation tasks (germane cognitive load factor), or the basic learning instruction (control group). Cognitive load was measured by the rhythm method (Park and Brünken 2015), the index of cognitive activity (ICA) (Marshall 2007), and the subjective ratings of mental effort and task difficulty (Paas 1992). Eye-tracking data were used to analyze the attention allocation and as an indicator for cognitive activity. The results show a significantly higher cognitive load for the mental animation group in contrast to the control and the seductive detail group, indicated by rhythm method and subjective ratings, as well as a higher cognitive activity, indicated by eye tracking. Furthermore, the mental animation group shows significantly higher comprehension performance in contrast to the seductive detail group and significantly higher transfer performance in contrast to the control group. The ICA values showed no significant differences in cognitive load. The results provide evidence for the benefits of combining eye-tracking analysis and the results of cognitive load ratings or secondary task performance for a direct and continuous cognitive load assessment and for a differentiating access to the single cognitive load factors.     

Gender and online health information: a partitioned technology assessment

Objective: To examine the extent to which health information seeking behaviors vary across genders or are differentially associated with access to computers, the Internet, and online health information. Research design: Stratified survey, data analysis. Methods: Using binary logistic regression we examine information seeking differences between demographic groups. Questions addressed include: 1) Are any identified groups significantly underserved regarding access to computers, access to the Internet, and preferences for seeking online health information, and 2) have differences between gender groups in access to computers, Internet services and online health information narrowed, remained constant, or widened over recent years, following recent national initiatives to narrow the technology gap for underserved populations? Outcomes: Information seeking variation across gender groups and between technologies was at times significant. There was little difference in the access to computer between females and males. In 2002, 75.4% and 73.1% of female and male participants reported that they occasionally use computers, respectively. In 2000, the respective figures were 72.4% and 72.7%. The rates of use of Internet services among computer users, however, were quite different between female and male (P_{at 2002}= 0.0002 and P_{at 2000}= 0.0082) and the disparity in 2000 (OR = 0.7366 [0.5870, 0.9243]) increased in 2002 (OR = 0.5675 [0.4222, 0.7627]). The odds ratios (OR) indicate that females were 0.7366 and 0.5675 times less likely to use computers than male counterparts in 2000 and 2002, respectively. Conclusion: Recent technology initiatives in the US aimed at reducing disparities in access to online resources appear to have had little effect in facilitating equal access to web‐based health information.     

HUMAN SUBJECTS AND COGNITIVE AGING RESEARCH: A UNIQUE SOLUTION TO A PERENNIAL PROBLEM

A fundamental concern of cognitive aging researchers is to find a representative sample of healthy, older adults who are willing to participate in experimental research. There are essentially two methods for marshalling a sizable body of older research participants. One can solicit the aid of local community‐dwelling adults through civic and church‐related organizations. Alternatively, one can travel to specific locations where elderly people are likely to congregate, for example, a retirement community. In this article, we describe our experiences with these two methods of research‐participant recruitment. The processes involved in both securing and utilizing a local body of research volunteers are presented first. We then discuss two subject‐testing expeditions outside of the university environment that have been highly successful. In the final section, we contrast selected demographic characteristics of our local and off‐site research volunteers and discuss the implications of differences between these two populations for conducting research with aged people.     

Validation of the Korean version Gender Role Conflict Scale for Adolescents

The objective of this study was to examine the usefulness of the Korean version of the Gender Role Conflict Scale for Adolescents (GRCS-A; Blazina et al. 2005) in Korea. Korean high school students (N = 374) completed the K-GRCS-A. Results of confirmatory factor analysis supported the original 4-factor structures. Reliability was acceptable to satisfactory limits. Further evidence of construct validity was found in modest correlations with psychological well-being variables. Taken together, this study sustained the utility of the K-GRCS-A.     

The Influence of Social Norms on Korean Wives’ Intention to Talk with Their Husbands about the Equal Division of Housework

Currently, Korean males see the equal division of housework more positively than in the past. However, a large gap still exists between the attitude and the actual behaviour of the equal amount of housework. Interpersonal communication can be used to reduce this gap. The theory of planned behaviour and social norms approach are the theoretical frameworks that guide the study. The purpose of the study is to examine how social norms are influencing Korean wives’ intention to talk to their husbands about the equal division of housework.     

Ubiquitous Learning Environment as a Solution to Education Problem

Ubiquitous learning means the intelligent learning environment that enables people to learn using any terminal at any place and at any time no matter what the contents may be.This is different from the existing method of learning the information through the internet or studying at specific place,such as school or library,and so on.People do not need to go to specific place at specific time to access the information that they want,but the learning information finds its way to people,which is the biggest difference from the existing method. Ubiquitous learning aims to solve current problems of education in more creative and learner-oriented way by creating an education environment where learners can learn with any terminal anytime and anywhere without regard to contents.The presentation this time would help promote the understanding of the Ubiquitous and explore the ubiquitous education environment that is capable of solving overall problems of education.In addition,it will propose a direction of ubiquitous learning scenario and the change in the educational environment.