966 resultados para Vaccine Efficacy


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In some wilderness areas, wildlife encounter vehicles disrupt their behaviour and habitat use. Changing driver behaviour has been proposed where bans on vehicle use are politically unpalatable, but the efficacy of vehicle setbacks and reduced speeds remains largely untested. We characterised bird-vehicle encounters in terms of driver behaviour and the disturbance caused to birds, and tested whether spatial buffers or lower speeds reduced bird escape responses on open beaches. Focal observations showed that: i) most drivers did not create sizeable buffers between their vehicles and birds; ii) bird disturbance was frequent; and iii) predictors of probability of flushing (escape) were setback distance and vehicle type (buses flushed birds at higher rates than cars). Experiments demonstrated that substantial reductions in bird escape responses required buffers to be wide (> 25 m) and vehicle speeds to be slow (< 30 km h-1). Setback distances can reduce impacts on wildlife, provided that they are carefully designed and derived from empirical evidence. No speed or distance combination we tested, however, eliminated bird responses. Thus, while buffers reduce response rates, they are likely to be much less effective than vehicle-free zones (i.e. beach closures), and rely on changes to current driver behaviour

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Recent evidence suggests that a subset of hepatocellular carcinomas (HCCs) are derived from liver cancer stem cells (LCSCs). In order to isolate and characterize LCSCs, reliable markers that are specific to these cells are required. We evaluated the efficacy of a range of cancer stem cell (CSC) markers in isolating and characterizing LCSCs. We show that the most widely used CSC markers are not specific to LCSCs. By western analysis, protein expression of the common markers showed no significant difference between HCC tumor tissues and adjacent non-cancerous liver. Further, isolation of LCSCs from common HCC cell lines using FACScan and microbeads showed no consistent marker expression pattern. We also show that LCSCs have unique subtypes. Immunohistochemistry of HCC tissues showed that different HCCs express unique combinations of LCSC markers. Quantitative real-time polymerase chain reaction analysis showed that LCSCs isolated using different markers in the same HCC phenotype had different expression profiles. Likewise, LCSCs isolated from different HCC phenotypes with the same marker also had unique expression profiles and displayed varying resistance profiles to Sorafenib. Thus, using a range of commonly used CSC markers in HCCs and cell lines, we demonstrate that currently available markers are not specific for LCSCs. LCSCs have unique subtypes that express distinctive combinations of LCSC markers and altered drug resistance profiles, making their identification problematic.

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Background
Undergraduate engineering students require exposure to an appropriate level of practical activities to complement the theory delivered in their course. This not only serves the purpose of catering to students’ different learning styles but in contributing to developing practical skills important to achieving an adequate level of job-readiness. The mode by which practical activities are implemented can vary widely across different units of study and different institutions. Electronics practicals within the School of Engineering at Deakin University have traditionally involved the construction and analysis of bread board circuits. Recently however, the practicals have changed to utilise modern computer-integrated Lab Volt FACET board equipment.


Purpose
This paper discusses electronics practicals using two very different types of laboratory equipment and reports on student perceived efficacy. The aim of the study is to gain an understanding of student perceptions so as to be able to refine the practicals to increase student engagement.

Design / method
This paper discusses two very different types of laboratory equipment employed in electronics practicals within the School of Engineering at Deakin University. This study focuses on students in electronics-related engineering disciplines and their perceived efficacy of the different equipment with the aim of providing valuable insight regarding student engagement. Survey data was collected from first and second year students who had completed successive classes using the different types of laboratory equipment.

Results
When compared with the electronics practicals and equipment previously used at Deakin University, the Lab Volt FACET boards provide a well-structured and resource efficient method for conducting practicals. The preliminary survey results indicate that there are mixed preferences for which type of laboratory equipment students perceive to be the better learning tool. The results also indicate that these perceptions appear to align with students in specific disciplines. These observations suggest that discipline specific characteristics of students are an important consideration in achieving improved student engagement and a positive learning experience.

Conclusions
The outcomes of the preliminary study suggest that there are discipline specific characteristics which affect students’ perceptions of the efficacy of laboratory equipment. These outcomes will assist Deakin’s School of Engineering to refine the use of the Lab Volt FACET board laboratory equipment to achieve improved student engagement. Future research will build upon these findings to investigate expectations of students in different disciplines and whether there is a difference in preferred learning and any correlation to student perceptions.

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Self-efficacy is a belief. It can encourage or hamper students from learning to their full potential. Students who are efficacious are more motivated, more persistent to meet their goals and are more likely to take learning risks. The research into the self-efficacy of students classified as verbally or non-verbally gifted is in its infancy. This book details a Doctoral dissertation that investigated the written English self-efficacy of adolescent students. Results identified verbally gifted students had higher written English self-efficacy, were more intrinsically motivated, had higher levels of creativity and wrote superior essays compared to non-verbally gifted and non-gifted students. Findings highlighted differences between gender as female student?s recorded higher self-efficacy and written English performance scores and interestingly, students from lower socio-economic backgrounds reported higher self-efficacy compared to students from higher socio-economic backgrounds. Pedagogical implications are considered with teachers encouraged to realise the impact of self-efficacy upon student learning, motivation and persistence regardless of their academic ability.

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Objective To investigate the short-term efficacy of a multicomponent intervention to reduce office workers' sitting time. Methods Allocation for this non-randomized controlled trial (n = 43 participants; 56% women; 26–62 years; Melbourne, Australia) was by office floor, with data collected during July–September 2011. The 4-week intervention emphasized three key messages: “Stand Up, Sit Less, Move More” and comprised organizational, environmental, and individual elements. Changes in minutes/day at the workplace spent sitting (primary outcome), in prolonged sitting (sitting time accumulated in bouts ≥ 30 min), standing, and moving were objectively measured (activPAL3). Results Relative to the controls, the intervention group significantly reduced workplace sitting time (mean change [95%CI]: − 125 [− 161, − 89] min/8-h workday), with changes primarily driven by a reduction in prolonged sitting time (− 73 [− 108, − 40] min/8-h workday). Workplace sitting was almost exclusively replaced by standing (+ 127 [+ 92, + 162] min/8-h workday) with non-significant changes to stepping time (− 2 [− 7, + 4] min/8-h workday) and number of steps (− 70 [− 350, 210]). Conclusions This multicomponent workplace intervention demonstrated that substantial reductions in sitting time are achievable in an office setting. Larger studies with longer timeframes are needed to assess sustainability of these changes, as well as their potential longer-term impacts on health and work-related outcomes.

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