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251.
研究大学生群体新冠疫苗科普信息搜寻意愿影响因素,有助于更好地开展针对该群体的新冠疫苗科普工作。目前,对信息搜寻行为中情感因素影响的研究并不完善,对恐惧的作用缺乏研究。本文采用问卷调查法和结构方程模型对大学生群体新冠疫苗科普信息搜寻意愿影响因素进行分析。研究发现:感知严重性和感知易感性正向影响恐惧;恐惧、态度、主观规范、知觉行为控制正向影响新冠疫苗在线科普信息搜寻意愿;面对新冠疫苗负面信息,女性恐惧感高于男性,年龄与恐惧和搜寻意愿呈显著负相关,女性、人文社科类学生具有更强的搜寻意愿。因此,基于研究提出如下建议:第一,新冠疫苗科普信息传播应以传播科学知识、回应公众关切、缓解公众恐惧为首要目标,切断“信息疫情”的蔓延;第二,可适当采用恐惧诉求,发挥人际传播的作用,以提升大学生新冠疫苗科普信息搜寻意愿;第三,要提升男性搜寻意愿,针对男性和人文社科类大学生开展精准科普,也要缓解女性恐惧感。 相似文献
252.
以对虾白斑病毒DNA为模板扩增出Vp28基因,经限制性内切酶(SmaI,Not I)酶切后按正确的读码框顺序插入到pGEX-4T-2表达载体上,重组质粒转化大肠杆菌,经菌落PCR和质粒双酶切鉴定、序列测定确认,证实成功地构建了Vp28基因原核表达载体.转化菌经IPTG诱导表达,SDS-PAGE显示有与预期大小约52kD相吻合的融合蛋白带,18℃诱导24h后获得了可溶性表达的目的蛋白,采用Glutathione Sepharose 4B亲和层析对重组蛋白进行纯化,获得了纯度很高的目的蛋白. 相似文献
253.
以凡纳滨对虾为研究对象,通过RT-PCR技术扩增出铁蛋白(Ferritin)基因,经特定的酶切(Notl,Smal)后插入到表达质粒pGEX-4T-2上构建表达载体,重组质粒转化大肠杆菌.经菌落PCR和质粒双酶切鉴定确认,证实成功地构建了对虾铁蛋白基因的原核表达载体.再对重组菌用IPTG诱导表达,采用Glutathione Sepharose4B亲和层析得到目的蛋白用于制备抗体,为研究铁蛋白在对虾抗病毒免疫中的作用奠定基础. 相似文献
254.
Brian R. Belland 《Educational Psychology Review》2011,23(4):577-600
Problem solving is an important skill in the knowledge economy. Research indicates that the development of problem solving
skills works better in the context of instructional approaches centered on real-world problems. But students need scaffolding
to be successful in such instruction. In this paper I present a conceptual framework for understanding the effects of scaffolding.
First, I discuss the ultimate goal of scaffolding—the transfer of responsibility—and one way that scholars have conceptualized
promoting this outcome (fading). Next, I describe an alternative way to conceptualize transfer of responsibility through the
lens of distributed cognition and discuss how this lens informs how to promote transfer of responsibility. Then I propose
guidelines for the creation of problem solving scaffolds to support transfer of responsibility and discuss them in light of
the literature. 相似文献
255.
Woei Hung 《Educational technology research and development : ETR & D》2011,59(4):529-552
The success of an intervention depends not only upon its theoretical soundness, but also on proper implementation that reflects
the guidelines derived from its theoretical conception. Debates surrounding the effectiveness of problem-based learning (PBL)
have focused on its theoretical conception and students’ learning outcomes, but implementation is seemingly absent from the
picture. This paper attempts to describe what research evidence is needed to fill in this missing information and provide
a clearer picture of PBL. The author examines current PBL implementation practices and identifies potentially confounding
variables that may play a role in inconsistent or conflicting research results in PBL. For example, various models of PBL
have been developed and implemented to afford the specific instructional needs of the institution or learner population. These
PBL models are in fact quite different in terms of the nature of problem solving and the degrees of self-directed learning,
which theoretically, should result in different types of learning outcomes. Without distinguishing the models used, the results
of comparative PBL research could have been confounded. Furthermore, human factors are another set of confounding variables
that could influence the students’ learning processes and consequently affect PBL implementations and research results. To
remedy these problems and reach PBL’s full potential, as well as obtain a more accurate picture of PBL as an instructional
method and its effects on students’ learning, some fundamental changes are needed. 相似文献
256.
Akindele Matthew Ige 《Early Childhood Education Journal》2011,39(2):161-167
Early childhood is a critical period of rapid physical, cognitive, and psycho-social development of a child. The quality of
care and education which a child receives at this crucial age will determine to a great extent the level of his/her physical
and cognitive development in the future. In Nigeria, Early Childhood Care, Development and Education (ECCDE) is an aspect
of Universal Basic Education which was introduced in 1999 to increase the access of children to basic education and improve
the state of education in the country. While all hands are on deck to ensure successful implementation and achievement of
the objectives of the scheme, it is unfortunate that ECCDE is facing some challenges thus making it unrecognized in Nigeria.
This paper examines the challenges of early childhood education in Nigeria. To improve the situation, the following measures
are recommended: establishment of more public crèche, kindergarten, and nursery schools by the government; enforcement of
the use of mother tongue in the teaching of children; training more personnel in the field of early childhood education in
tertiary institutions; and introducing unified curriculum as well as providing more infrastructures. 相似文献
257.
Lynne Cherry 《Journal of Science Education and Technology》2011,20(2):208-213
Lynne Cherry Brandwein Lecture March 2010 National Science Teachers Association (NSTA) Conference, Philadelphia, PA. Young
Voices on Climate Change: Inspired and Empowered Youth Tackle Climate Science and Find Climate Solutions. As a child, Lynne
Cherry was profoundly connected to the natural world and a special place. She watched the destruction of her world. Now, through
her Young Voices on Climate Change project, she is trying to give teachers and young people the tools to prevent planetary
meltdown on a greater scale. Global climate change is upon us and the need for education and action is immediate. Outreach,
visual storytelling, and scientific understanding are especially necessary in light of the recent polls that show that the
public is becoming more confused and less concerned about climate change. Cherry’s climate book, co-authored with photojournalist
Gary Braasch, and her Young Voices on Climate Change films feature climate solutions. They’re about win–win—save the environment,
protect human health, reduce global warming gases, demonstrate youth making a difference with practical tools, motivate engagement
in climate science, take pride in increased science literacy, reach young people through their hearts as well as their minds,
and save money. Although young people can help their parents, peers and communities understand climate science, they can also
show them that reducing CO2 is in their economic interest, and spur them to take action. School carbon reduction initiatives are spilling over into communities
yielding measurable results in both global warming gas reductions and significant monetary savings. 相似文献
258.
Part II of “Reclaiming Kindergarten” continues the discussion related to responding to the crisis in today’s kindergarten.
In Part II, two policy questions are posed, the answers to which seek to respond to this continuing crisis. The questions
center on issues related to engaging families in kindergarten and the need to consider a new early childhood paradigm where
kindergarten is part of a continuous and seamless educational experience spanning prekindergarten through third grade. As
in Part I, examples of classroom practice are used to illustrate the effective implementation of these principles in a kindergarten
classroom. 相似文献
259.
The focus of this article is on articulating the importance of teacher development of constructs about homeless children and
families and examining factors that influence teachers’ perceptions of children and families who are homeless or at high-risk
of becoming homeless. The article also explores some strategies to support teachers in transforming their perceptions of homeless
children and provides case examples of how this process can work. Three case studies explore how teacher educators and practicing
teachers can work together to reflect on their own perceptions of homeless children from high-poverty backgrounds and how
educators were able to transform their own perceptions in being able to better serve their students. 相似文献
260.
Early childhood teacher educators frequently enhance their teaching by reading children’s books to their adult students. It
is not unusual for faculty outside of early childhood to question devoting precious class time to read-alouds which they may
consider a curious, if not frivolous, instructional strategy. Quality children’s literature can, however, enhance students’
experiences in the college classroom, contribute to their understanding of course content, promote their personal growth and
self-understanding, increase their appreciation for quality children’s literature, and enhance their ability to integrate
storybooks into their own teaching. Children’s books often capture a child’s point of view. They have the potential to provide
historical or cultural perspectives on children and families. They also can lead to the examination of universal truths and
can facilitate the discussion of sensitive or emotional issues A list of books with suggested uses is included. 相似文献